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Scott H, Martin PE, Graham SV. Modulation of connexin 43 in viral infections. Tumour Virus Res 2024; 18:200296. [PMID: 39522757 PMCID: PMC11607658 DOI: 10.1016/j.tvr.2024.200296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2024] [Revised: 11/05/2024] [Accepted: 11/05/2024] [Indexed: 11/16/2024] Open
Abstract
Connexins are essential for intercellular communication through gap junctions and the maintenance of cellular and tissue homeostasis. Connexin 43 (Cx43) is the most ubiquitously expressed connexin. As well as regulating homeostasis, Cx43 hemichannels and gap junctions play important roles in inflammation and the immune response. This, coupled with a range of non-channel functions performed by Cx43 makes it an attractive target for viruses. Recently, several groups have begun to explore the relationship between Cx43 and viral infection, with a diverse array of viruses being found to alter Cx43 hemichannels/gap junctions. Importantly, this includes several small DNA tumour viruses, which may target Cx43 to promote tumorigenesis. This review focuses on the ability of selected RNA/DNA viruses and retroviruses to either positively or negatively regulate Cx43 hemichannels and gap junctions in order to carry out their lifecycles. The role of Cx43 regulation by tumour viruses is also discussed in relation to tumour progression.
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Affiliation(s)
- Harry Scott
- MRC-University of Glasgow Centre for Virus Research, School of Infection and Immunity, College of Medical Veterinary and Life Sciences, University of Glasgow, Garscube Estate, Glasgow, G61 1QH, UK.
| | - Patricia E Martin
- Department of Biological and Biomedical Science, School of Health and Life Sciences, Glasgow Caledonian University, Glasgow, G4 0BA, UK.
| | - Sheila V Graham
- MRC-University of Glasgow Centre for Virus Research, School of Infection and Immunity, College of Medical Veterinary and Life Sciences, University of Glasgow, Garscube Estate, Glasgow, G61 1QH, UK.
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2
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Rodríguez-Candela Mateos M, Carpintero-Fernández P, Freijanes PS, Mosquera J, Nebril BA, Mayán MD. Insights into the role of connexins and specialized intercellular communication pathways in breast cancer: Mechanisms and applications. Biochim Biophys Acta Rev Cancer 2024; 1879:189173. [PMID: 39154967 DOI: 10.1016/j.bbcan.2024.189173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2024] [Revised: 07/31/2024] [Accepted: 08/14/2024] [Indexed: 08/20/2024]
Abstract
Gap junctions, membrane-based channels comprised of connexin proteins (Cxs), facilitate direct communication among neighbouring cells and between cells and the extracellular space through their hemichannels. The normal human breast expresses various Cxs family proteins, such as Cx43, Cx30, Cx32, Cx46, and Cx26, crucial for proper tissue development and function. These proteins play a significant role in breast cancer development, progression, and therapy response. In primary tumours, there is often a reduction and cytoplasmic mislocalization of Cx43 and Cx26, while metastatic lesions show an upregulation of these and other Cxs. Although existing research predominantly supports the tumour-suppressing role of Cxs in primary carcinomas through channel-dependent and independent functions, controversies persist regarding their involvement in the metastatic process. This review aims to provide an updated perspective on Cxs in human breast cancer, with a specific focus on intrinsic subtypes due to the heterogeneous nature of this disease. Additionally, the manuscript will explore the role of Cxs in immune interactions and novel forms of intercellular communication, such as tunneling nanotubes and extracellular vesicles, within the breast tumour context and tumour microenvironment. Recent findings suggest that Cxs hold potential as therapeutic targets for mitigating metastasis and drug resistance. Furthermore, they may serve as novel biomarkers for cancer prognosis, offering promising avenues for future research and clinical applications.
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Affiliation(s)
- Marina Rodríguez-Candela Mateos
- Instituto de Investigación Biomédica de A Coruña (INIBIC), Servizo Galego de Saúde (SERGAS), Xubias de Arriba, 84, 15006 A Coruña, Spain
| | - Paula Carpintero-Fernández
- Instituto de Investigación Biomédica de A Coruña (INIBIC), Servizo Galego de Saúde (SERGAS), Xubias de Arriba, 84, 15006 A Coruña, Spain; CellCOM Research Group, Center for Research in Nanomaterials and Biomedicine (CINBIO), Universidade de Vigo, Edificio Olimpia Valencia, Campus Universitario Lagoas Marcosende, 36310 Vigo, Spain; Galicia Sur Health Research Institute (IIS Galicia Sur), SERGAS, Spain
| | - Paz Santiago Freijanes
- Instituto de Investigación Biomédica de A Coruña (INIBIC), Servizo Galego de Saúde (SERGAS), Xubias de Arriba, 84, 15006 A Coruña, Spain; Anatomic Pathology Department, Breast Unit, A Coruña University Hospital, SERGAS, A Coruña, Spain
| | - Joaquin Mosquera
- Instituto de Investigación Biomédica de A Coruña (INIBIC), Servizo Galego de Saúde (SERGAS), Xubias de Arriba, 84, 15006 A Coruña, Spain; Surgery Department, Breast Unit, A Coruña University Hospital, SERGAS, A Coruña, Spain
| | - Benigno Acea Nebril
- Instituto de Investigación Biomédica de A Coruña (INIBIC), Servizo Galego de Saúde (SERGAS), Xubias de Arriba, 84, 15006 A Coruña, Spain; Surgery Department, Breast Unit, A Coruña University Hospital, SERGAS, A Coruña, Spain
| | - María D Mayán
- Instituto de Investigación Biomédica de A Coruña (INIBIC), Servizo Galego de Saúde (SERGAS), Xubias de Arriba, 84, 15006 A Coruña, Spain; CellCOM Research Group, Center for Research in Nanomaterials and Biomedicine (CINBIO), Universidade de Vigo, Edificio Olimpia Valencia, Campus Universitario Lagoas Marcosende, 36310 Vigo, Spain; Galicia Sur Health Research Institute (IIS Galicia Sur), SERGAS, Spain.
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3
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Papadakos SP, Chatzikalil E, Arvanitakis K, Vakadaris G, Stergiou IE, Koutsompina ML, Argyrou A, Lekakis V, Konstantinidis I, Germanidis G, Theocharis S. Understanding the Role of Connexins in Hepatocellular Carcinoma: Molecular and Prognostic Implications. Cancers (Basel) 2024; 16:1533. [PMID: 38672615 PMCID: PMC11048329 DOI: 10.3390/cancers16081533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 04/15/2024] [Accepted: 04/16/2024] [Indexed: 04/28/2024] Open
Abstract
Connexins, a family of tetraspan membrane proteins forming intercellular channels localized in gap junctions, play a pivotal role at the different stages of tumor progression presenting both pro- and anti-tumorigenic effects. Considering the potential role of connexins as tumor suppressors through multiple channel-independent mechanisms, their loss of expression may be associated with tumorigenic activity, while it is hypothesized that connexins favor the clonal expansion of tumor cells and promote cell migration, invasion, and proliferation, affecting metastasis and chemoresistance in some cases. Hepatocellular carcinoma (HCC), characterized by unfavorable prognosis and limited responsiveness to current therapeutic strategies, has been linked to gap junction proteins as tumorigenic factors with prognostic value. Notably, several members of connexins have emerged as promising markers for assessing the progression and aggressiveness of HCC, as well as the chemosensitivity and radiosensitivity of hepatocellular tumor cells. Our review sheds light on the multifaceted role of connexins in HCC pathogenesis, offering valuable insights on recent advances in determining their prognostic and therapeutic potential.
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Affiliation(s)
- Stavros P. Papadakos
- First Department of Pathology, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece; (S.P.P.); (E.C.)
| | - Elena Chatzikalil
- First Department of Pathology, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece; (S.P.P.); (E.C.)
| | - Konstantinos Arvanitakis
- Division of Gastroenterology and Hepatology, First Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (K.A.); (G.V.)
- Basic and Translational Research Unit, Special Unit for Biomedical Research and Education, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece
| | - Georgios Vakadaris
- Division of Gastroenterology and Hepatology, First Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (K.A.); (G.V.)
| | - Ioanna E. Stergiou
- Pathophysiology Department, School of Medicine, National and Kapodistrian University of Athens, 11527 Athens, Greece; (I.E.S.); (M.-L.K.)
| | - Maria-Loukia Koutsompina
- Pathophysiology Department, School of Medicine, National and Kapodistrian University of Athens, 11527 Athens, Greece; (I.E.S.); (M.-L.K.)
| | - Alexandra Argyrou
- Academic Department of Gastroenterology, Laikon General Hospital, Athens University Medical School, 11527 Athens, Greece; (A.A.); (V.L.)
| | - Vasileios Lekakis
- Academic Department of Gastroenterology, Laikon General Hospital, Athens University Medical School, 11527 Athens, Greece; (A.A.); (V.L.)
| | | | - Georgios Germanidis
- Division of Gastroenterology and Hepatology, First Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece; (K.A.); (G.V.)
- Basic and Translational Research Unit, Special Unit for Biomedical Research and Education, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54636 Thessaloniki, Greece
| | - Stamatios Theocharis
- First Department of Pathology, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece; (S.P.P.); (E.C.)
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Baker KM, Abt M, Doud EH, Oblak AL, Yeh ES. Mapping the Anti-Cancer Activity of α-Connexin Carboxyl-Terminal (aCT1) Peptide in Resistant HER2+ Breast Cancer. Cancers (Basel) 2024; 16:423. [PMID: 38275864 PMCID: PMC10814893 DOI: 10.3390/cancers16020423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 01/10/2024] [Accepted: 01/17/2024] [Indexed: 01/27/2024] Open
Abstract
Connexin 43 (Cx43) is a protein encoded by the GJA1 gene and is a component of cell membrane structures called gap junctions, which facilitate intercellular communication. Prior evidence indicates that elevated GJA1 expression in the HER2-positive (HER2+) subtype of breast cancer is associated with poor prognosis. Prior evidence also suggests that HER2+ breast cancers that have become refractory to HER2-targeted agents have a loss of Cx43 gap junction intercellular communication (GJIC). In this study, a Cx43-targeted agent called alpha-connexin carboxyl-terminal peptide (aCT1) is examined to determine whether GJIC can be rescued in refractory HER2+ breast cancer cells. A proposed mechanism of action for aCT1 is binding to the tight junction protein Zonal Occludens-1 (ZO-1). However, the true scope of activity for aCT1 has not been explored. In this study, mass spectrometry proteomic analysis is used to determine the breadth of aCT1-interacting proteins. The NanoString nCounter Breast Cancer 360 panel is also used to examine the effect of aCT1 on cancer signaling in HER2+ breast cancer cells. Findings from this study show a dynamic range of binding partners for aCT1, many of which regulate gene expression and RNA biology. nCounter analysis shows that a number of pathways are significantly impacted by aCT1, including upregulation of apoptotic factors, leading to the prediction and demonstration that aCT1 can boost the cell death effects of cisplatin and lapatinib in HER2+ breast cancer cells that have become resistant to HER2-targeted agents.
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Affiliation(s)
- Kimberly M. Baker
- Department of Biology, University of Indianapolis, Indianapolis, IN 46227, USA;
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Melissa Abt
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Emma H. Doud
- Melvin and Bren Simon Comprehensive Cancer Center, Indiana University School of Medicine, Indianapolis, IN 46202, USA;
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Adrian L. Oblak
- Department of Radiology and Imaging Sciences, Indiana University School of Medicine, Indianapolis, IN 46202, USA;
- Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Elizabeth S. Yeh
- Department of Pharmacology and Toxicology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Melvin and Bren Simon Comprehensive Cancer Center, Indiana University School of Medicine, Indianapolis, IN 46202, USA;
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Mulkearns-Hubert EE, Rhoades EE, Ben-Salem S, Bharti R, Hajdari N, Johnson S, Myers A, Smith IN, Bandyopadhyay S, Eng C, Downs E, Lathia JD, Reizes O. Targeting NANOG and FAK via Cx26-derived Cell-penetrating Peptides in Triple-negative Breast Cancer. Mol Cancer Ther 2024; 23:56-67. [PMID: 37703580 PMCID: PMC10840808 DOI: 10.1158/1535-7163.mct-21-0783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 02/28/2023] [Accepted: 09/11/2023] [Indexed: 09/15/2023]
Abstract
Triple-negative breast cancer (TNBC) represents the most lethal and treatment-resistant breast cancer subtype with limited treatment options. We previously identified a protein complex unique to TNBC composed of the gap junction protein connexin 26 (Cx26), the pluripotency transcription factor NANOG, and focal adhesion kinase (FAK). We sought to determine whether a peptide mimetic of the interaction region of Cx26 attenuated tumor growth in preclinical models. We designed peptides based on Cx26 juxtamembrane domains and performed binding experiments with NANOG and FAK using surface plasmon resonance. Binding studies revealed that the Cx26 C-terminal tail and intracellular loop bound to NANOG and FAK with submicromolar-to-micromolar affinity and that a 5-amino acid sequence in the C-terminal tail of Cx26 (RYCSG) was sufficient for binding. Peptides with high affinity were engineered with a cell-penetrating antennapedia sequence and assessed in functional assays including cell proliferation, tumorsphere formation, and in vivo tumor growth, and downstream signaling changes were measured. The cell-penetrating Cx26 peptide (aCx26-pep) disrupted self-renewal while reducing nuclear FAK and NANOG and inhibiting NANOG target gene expression in TNBC cells but not luminal mammary epithelial cells. In vivo, aCx26-pep reduced tumor growth and proliferation and induced cell death. Here, we provide proof-of-concept that a Cx26 peptide-based strategy inhibits growth and alters NANOG activity specifically in TNBC, indicating the therapeutic potential of this targeting approach.
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Affiliation(s)
- Erin E. Mulkearns-Hubert
- Department of Cardiovascular and Metabolic Sciences, Cancer Impact Area, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, Ohio 44195
- Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, 9500 Euclid Avenue, Cleveland, Ohio 44195
| | - Emily Esakov Rhoades
- Department of Cardiovascular and Metabolic Sciences, Cancer Impact Area, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, Ohio 44195
| | - Salma Ben-Salem
- Department of Cardiovascular and Metabolic Sciences, Cancer Impact Area, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, Ohio 44195
| | - Rashmi Bharti
- Department of Cardiovascular and Metabolic Sciences, Cancer Impact Area, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, Ohio 44195
| | - Nicole Hajdari
- Department of Cardiovascular and Metabolic Sciences, Cancer Impact Area, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, Ohio 44195
| | - Sadie Johnson
- Department of Cardiovascular and Metabolic Sciences, Cancer Impact Area, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, Ohio 44195
| | - Alex Myers
- Department of Cardiovascular and Metabolic Sciences, Cancer Impact Area, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, Ohio 44195
| | - Iris Nira Smith
- Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195
| | - Smarajit Bandyopadhyay
- Molecular Biotechnology Core, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, Ohio 44195
| | - Charis Eng
- Genomic Medicine Institute, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195
| | - Erinn Downs
- Department of Pathology, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, Ohio 44195
| | - Justin D. Lathia
- Department of Cardiovascular and Metabolic Sciences, Cancer Impact Area, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, Ohio 44195
- Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, 9500 Euclid Avenue, Cleveland, Ohio 44195
- Case Comprehensive Cancer Center, 10900 Euclid Ave. Cleveland, OH 44106
| | - Ofer Reizes
- Department of Cardiovascular and Metabolic Sciences, Cancer Impact Area, Lerner Research Institute, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, Ohio 44195
- Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, 9500 Euclid Avenue, Cleveland, Ohio 44195
- Case Comprehensive Cancer Center, 10900 Euclid Ave. Cleveland, OH 44106
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6
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Schulz B, Schumacher V, Ngezahayo A, Maier-Begandt D, Schadzek N, Wilhelm J, Weidner W, Pilatz A, Fietz D, Kliesch S, Schnepel N, Hambruch N, Rode K, Langeheine M, Brehm R. Analysis of connexin 43, connexin 45 and N-cadherin in the human sertoli cell line FS1 and the human seminoma-like cell line TCam-2 in comparison with human testicular biopsies. BMC Cancer 2023; 23:232. [PMID: 36899312 PMCID: PMC10007848 DOI: 10.1186/s12885-023-10696-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 03/01/2023] [Indexed: 03/12/2023] Open
Abstract
BACKGROUND Germ cell tumors are relatively common in young men. They derive from a non-invasive precursor, called germ cell neoplasia in situ, but the exact pathogenesis is still unknown. Thus, further understanding provides the basis for diagnostics, prognostics and therapy and is therefore paramount. A recently developed cell culture model consisting of human FS1 Sertoli cells and human TCam-2 seminoma-like cells offers new opportunities for research on seminoma. Since junctional proteins within the seminiferous epithelium are involved in cell organization, differentiation and proliferation, they represent interesting candidates for investigations on intercellular adhesion and communication in context with neoplastic progression. METHODS FS1 and TCam-2 cells were characterized regarding gap-junction-related connexin 43 (Cx43) and connexin 45 (Cx45), and adherens-junction-related N-cadherin using microarray, PCR, Western blot, immunocytochemistry and immunofluorescence. Results were compared to human testicular biopsies at different stages of seminoma development via immunohistochemistry to confirm the cell lines' representativeness. Furthermore, dye-transfer measurements were performed to investigate functional cell coupling. RESULTS Cx43, Cx45 and N-cadherin mRNA and protein were generally detectable in both cell lines via qualitative RT-PCR and Western blot. Immunocytochemistry and immunofluorescence revealed a mainly membrane-associated expression of N-cadherin in both cell lines, but gene expression values were higher in FS1 cells. Cx43 expression was also membrane-associated in FS1 cells but barely detectable in TCam-2 cells. Accordingly, a high gene expression value of Cx43 was measured for FS1 and a low value for TCam-2 cells. Cx45 was primary located in the cytoplasm of FS1 and TCam-2 cells and revealed similar low to medium gene expression values in both cell lines. Overall, results were comparable with corresponding biopsies. Additionally, both FS1 and TCam-2 cells showed dye diffusion into neighboring cells. CONCLUSION The junctional proteins Cx43, Cx45 and N-cadherin are expressed in FS1 and TCam-2 cells at mRNA and/or protein level in different amounts and localizations, and cells of both lines are functionally coupled among each other. Concerning the expression of these junctional proteins, FS1 and TCam-2 cells are largely representative for Sertoli and seminoma cells, respectively. Thus, these results provide the basis for further coculture experiments evaluating the role of junctional proteins in context with seminoma progression.
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Affiliation(s)
- Birte Schulz
- Institute of Anatomy, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany.
| | - Valérie Schumacher
- Department of Urology and Medicine, Boston Children's Hospital, Boston, MA, USA.,Department of Surgery and Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Anaclet Ngezahayo
- Department of Cell Physiology and Biophysics, Institute of Cell Biology and Biophysics, Leibniz University Hannover, Hannover, Germany.,Center for Systems Neuroscience Hannover, University of Veterinary Medicine Hannover Foundation, Hannover, Germany
| | - Daniela Maier-Begandt
- Department of Cell Physiology and Biophysics, Institute of Cell Biology and Biophysics, Leibniz University Hannover, Hannover, Germany
| | - Nadine Schadzek
- Department of Cell Biology, Institute of Cell Biology and Biophysics, Leibniz University Hannover, Hannover, Germany
| | - Jochen Wilhelm
- Institute for Lung Health, Justus Liebig University Giessen, Giessen, Germany.,Universities of Giessen and Marburg Lung Center, Member of the German Center for Lung Research, Justus Liebig University Giessen, Giessen, Germany.,The Cardiopulmonary Institute, Justus Liebig University Giessen, Giessen, Germany
| | - Wolfgang Weidner
- Department of Urology, Pediatric Urology and Andrology, Justus Liebig University Giessen, Giessen, Germany
| | - Adrian Pilatz
- Department of Urology, Pediatric Urology and Andrology, Justus Liebig University Giessen, Giessen, Germany
| | - Daniela Fietz
- Department of Veterinary Anatomy, Histology and Embryology, Justus Liebig University Giessen, Giessen, Germany
| | - Sabine Kliesch
- Centre of Andrology and Reproductive Medicine, University of Muenster, Muenster, Germany
| | - Nadine Schnepel
- Institute of Anatomy, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Nina Hambruch
- Institute of Anatomy, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Kristina Rode
- Institute of Anatomy, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Marion Langeheine
- Institute of Anatomy, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
| | - Ralph Brehm
- Institute of Anatomy, University of Veterinary Medicine Hannover, Foundation, Hannover, Germany
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7
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Xu QR, Du XH, Huang TT, Zheng YC, Li YL, Huang DY, Dai HQ, Li EM, Fang WK. Role of Cell-Cell Junctions in Oesophageal Squamous Cell Carcinoma. Biomolecules 2022; 12:biom12101378. [PMID: 36291586 PMCID: PMC9599896 DOI: 10.3390/biom12101378] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 09/20/2022] [Accepted: 09/21/2022] [Indexed: 02/05/2023] Open
Abstract
Cell-cell junctions comprise various structures, including adherens junctions, tight junctions, desmosomes, and gap junctions. They link cells to each other in tissues and regulate tissue homeostasis in critical cellular processes. Recent advances in cell-cell junction research have led to critical discoveries. Cell-cell adhesion components are important for the invasion and metastasis of tumour cells, which are not only related to cell-cell adhesion changes, but they are also involved in critical molecular signal pathways. They are of great significance, especially given that relevant molecular mechanisms are being discovered, there are an increasing number of emerging biomarkers, targeted therapies are becoming a future therapeutic concern, and there is an increased number of therapeutic agents undergoing clinical trials. Oesophageal squamous cell carcinoma (ESCC), the most common histological subtype of oesophageal cancer, is one of the most common cancers to affect epithelial tissue. ESCC progression is accompanied by the abnormal expression or localisation of components at cell-cell junctions. This review will discuss the recent scientific developments related to the molecules at cell-cell junctions and their role in ESCC to offer valuable insights for readers, provide a global view of the relationships between position, construction, and function, and give a reference for future mechanistic studies, diagnoses, and therapeutic developments.
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Affiliation(s)
| | | | | | | | | | | | | | - En-Min Li
- Correspondence: (E.-M.L.); (W.-K.F.)
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8
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Van Campenhout R, Leroy K, Cooreman A, Tabernilla A, Cogliati B, Kadam P, Vinken M. Connexin-Based Channels in the Liver. Compr Physiol 2022; 12:4147-4163. [PMID: 35950654 DOI: 10.1002/cphy.c220007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Connexin proteins oligomerize in hexameric structures called connexin hemichannels, which then dock to form gap junctions. Gap junctions direct cell-cell communication by allowing the exchange of small molecules and ions between neighboring cells. In this way, hepatic gap junctions support liver homeostasis. Besides serving as building blocks for gap junctions, connexin hemichannels provide a pathway between the intracellular and the extracellular environment. The activation of connexin hemichannels is associated with acute and chronic liver pathologies. This article discusses the role of gap junctions and connexin hemichannels in the liver. © 2022 American Physiological Society. Compr Physiol 12:1-17, 2022.
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Affiliation(s)
- Raf Van Campenhout
- Entity of In Vitro Toxicology and Dermato-Cosmetology, Department of Pharmaceutical and Pharmacological Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Kaat Leroy
- Entity of In Vitro Toxicology and Dermato-Cosmetology, Department of Pharmaceutical and Pharmacological Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Axelle Cooreman
- Entity of In Vitro Toxicology and Dermato-Cosmetology, Department of Pharmaceutical and Pharmacological Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Andrés Tabernilla
- Entity of In Vitro Toxicology and Dermato-Cosmetology, Department of Pharmaceutical and Pharmacological Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Bruno Cogliati
- School of Veterinary Medicine and Animal Science, Department of Pathology, University of São Paulo, São Paulo, Brazil
| | - Prashant Kadam
- Entity of In Vitro Toxicology and Dermato-Cosmetology, Department of Pharmaceutical and Pharmacological Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Mathieu Vinken
- Entity of In Vitro Toxicology and Dermato-Cosmetology, Department of Pharmaceutical and Pharmacological Sciences, Vrije Universiteit Brussel, Brussels, Belgium
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9
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Generation and Characterization of an Inducible Cx43 Overexpression System in Mouse Embryonic Stem Cells. Cells 2022; 11:cells11040694. [PMID: 35203340 PMCID: PMC8869955 DOI: 10.3390/cells11040694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 02/07/2022] [Accepted: 02/09/2022] [Indexed: 11/17/2022] Open
Abstract
Connexins (Cx) are a large family of membrane proteins that can form intercellular connections, so-called gap junctions between adjacent cells. Cx43 is widely expressed in mammals and has a variety of different functions, such as the propagation of electrical conduction in the cardiac ventricle. Despite Cx43 knockout models, many questions regarding the biology of Cx43 in health and disease remain unanswered. Herein we report the establishment of a Cre-inducible Cx43 overexpression system in murine embryonic stem (ES) cells. This enables the investigation of the impact of Cx43 overexpression in somatic cells. We utilized a double reporter system to label Cx43-overexpressing cells via mCherry fluorescence and exogenous Cx43 via fusion with P2A peptide to visualize its distribution pattern. We proved the functionality of our systems in ES cells, HeLa cells, and 3T3-fibroblasts and demonstrated the formation of functional gap junctions based on dye diffusion and FRAP experiments. In addition, Cx43-overexpressing ES cells could be differentiated into viable cardiomyocytes, as shown by the formation of cross striation and spontaneous beating. Analysis revealed faster and more rhythmic beating of Cx43-overexpressing cell clusters. Thus, our Cx43 overexpression systems enable the investigation of Cx43 biology and function in cardiomyocytes and other somatic cells.
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10
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Unal YC, Yavuz B, Ozcivici E, Mese G. The role of connexins in breast cancer: from misregulated cell communication to aberrant intracellular signaling. Tissue Barriers 2022; 10:1962698. [PMID: 34355641 PMCID: PMC8794248 DOI: 10.1080/21688370.2021.1962698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 07/22/2021] [Accepted: 07/22/2021] [Indexed: 12/24/2022] Open
Abstract
In spite of clinical advancements and improved diagnostic techniques, breast cancers are the leading cause of cancer-associated deaths in women worldwide. Although 70% of early breast cancers can be cured, there are no efficient therapies against metastatic breast cancers. Several factors including connexins and gap junctions play roles in breast tumorigenesis. Connexins are critical for cellular processes as a linkage between connexin mutations and hereditary disorders demonstrated their importance for tissue homeostasis. Further, alterations in their expression, localization and channel activities were observed in many cancers including breast cancer. Both channel-dependent and independent functions of connexins were reported in initiation and progression of cancers. Unlike initial reports suggesting tumor suppressor functions, connexins and gap junctions have stage, context and isoform dependent effects in breast cancers similar to other cancers. In this review, we tried to describe the current understanding of connexins in tumorigenesis specifically in breast cancers.
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Affiliation(s)
- Yagmur Ceren Unal
- Faculty of Science, Department of Molecular Biology and Genetics, Izmir Institute of Technology, Urla, Izmir, Turkey
| | - Busra Yavuz
- Faculty of Science, Department of Molecular Biology and Genetics, Izmir Institute of Technology, Urla, Izmir, Turkey
| | - Engin Ozcivici
- Department of Bioengineering, Faculty of Engineering, Izmir Institute of Technology, Urla, Izmir, Turkey
| | - Gulistan Mese
- Faculty of Science, Department of Molecular Biology and Genetics, Izmir Institute of Technology, Urla, Izmir, Turkey
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11
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Leroy K, Silva Costa CJ, Pieters A, dos Santos Rodrigues B, Van Campenhout R, Cooreman A, Tabernilla A, Cogliati B, Vinken M. Expression and Functionality of Connexin-Based Channels in Human Liver Cancer Cell Lines. Int J Mol Sci 2021; 22:12187. [PMID: 34830068 PMCID: PMC8623148 DOI: 10.3390/ijms222212187] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 11/08/2021] [Accepted: 11/08/2021] [Indexed: 01/14/2023] Open
Abstract
Liver cancer cell lines are frequently used in vitro tools to test candidate anti-cancer agents as well as to elucidate mechanisms of liver carcinogenesis. Among such mechanisms is cellular communication mediated by connexin-based gap junctions. The present study investigated changes in connexin expression and gap junction functionality in liver cancer in vitro. For this purpose, seven human liver cancer cell lines, as well as primary human hepatocytes, were subjected to connexin and gap junction analysis at the transcriptional, translational and activity level. Real-time quantitative reverse transcription polymerase chain reaction analysis showed enhanced expression of connexin43 in the majority of liver cancer cell lines at the expense of connexin32 and connexin26. Some of these changes were paralleled at the protein level, as evidenced by immunoblot analysis and in situ immunocytochemistry. Gap junctional intercellular communication, assessed by the scrape loading/dye transfer assay, was generally low in all liver cancer cell lines. Collectively, these results provide a full scenario of modifications in hepatocyte connexin production and gap junction activity in cultured liver cancer cell lines. The findings may be valuable for the selection of neoplastic hepatocytes for future mechanistic investigation and testing of anti-cancer drugs that target connexins and their channels.
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Affiliation(s)
- Kaat Leroy
- Entity of In Vitro Toxicology and Dermato-Cosmetology, Department of Pharmaceutical and Pharmacological Sciences, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium; (K.L.); (A.P.); (B.d.S.R.); (R.V.C.); (A.C.); (A.T.)
| | - Cícero Júlio Silva Costa
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, Cidade Universitária, São Paulo 05508-270, Brazil; (C.J.S.C.); (B.C.)
| | - Alanah Pieters
- Entity of In Vitro Toxicology and Dermato-Cosmetology, Department of Pharmaceutical and Pharmacological Sciences, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium; (K.L.); (A.P.); (B.d.S.R.); (R.V.C.); (A.C.); (A.T.)
| | - Bruna dos Santos Rodrigues
- Entity of In Vitro Toxicology and Dermato-Cosmetology, Department of Pharmaceutical and Pharmacological Sciences, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium; (K.L.); (A.P.); (B.d.S.R.); (R.V.C.); (A.C.); (A.T.)
| | - Raf Van Campenhout
- Entity of In Vitro Toxicology and Dermato-Cosmetology, Department of Pharmaceutical and Pharmacological Sciences, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium; (K.L.); (A.P.); (B.d.S.R.); (R.V.C.); (A.C.); (A.T.)
| | - Axelle Cooreman
- Entity of In Vitro Toxicology and Dermato-Cosmetology, Department of Pharmaceutical and Pharmacological Sciences, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium; (K.L.); (A.P.); (B.d.S.R.); (R.V.C.); (A.C.); (A.T.)
| | - Andrés Tabernilla
- Entity of In Vitro Toxicology and Dermato-Cosmetology, Department of Pharmaceutical and Pharmacological Sciences, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium; (K.L.); (A.P.); (B.d.S.R.); (R.V.C.); (A.C.); (A.T.)
| | - Bruno Cogliati
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, Cidade Universitária, São Paulo 05508-270, Brazil; (C.J.S.C.); (B.C.)
| | - Mathieu Vinken
- Entity of In Vitro Toxicology and Dermato-Cosmetology, Department of Pharmaceutical and Pharmacological Sciences, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium; (K.L.); (A.P.); (B.d.S.R.); (R.V.C.); (A.C.); (A.T.)
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12
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Combinational treatment of gap junction enhancers and paclitaxel attenuates mammary tumor growth. Anticancer Drugs 2021; 31:353-358. [PMID: 31913199 DOI: 10.1097/cad.0000000000000879] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
A class of substituted quinolines (PQs) acts as a gap junction enhancer with the ability to increase the gap junctional intercellular communication in breast cancer cells. This study examined the effect of a combinational treatment of PQs and the antineoplastic drug paclitaxel in a xenograft animal model. Mice were implanted with estradiol-17ß (1.7 mg/pellet) before the injection of 1 × 10 T47D breast cancer cells subcutaneously into the inguinal region of mammary fat pad. Animals were treated intraperitoneally with DMSO (control), paclitaxel (10 mg/kg), PQ (25 mg/kg), or a combinational treatment of paclitaxel and PQ. There was no significant difference between the paclitaxel-treated animals and the control group after seven injections of treatment for 2 weeks. All mice treated with PQ had a significant decrease in mammary tumor growth. The combinational treatment of paclitaxel and PQ1 or PQ7 showed a reduction in tumor growth by 2.3- and 2.2-fold, respectively, compared to paclitaxel alone after seven treatments every 2 days. Molecular analysis indicated a significant increase of gap junction proteins and caspase signaling in PQ and paclitaxel-treated tissues compared to control. Furthermore, there is evidence of an upregulation of Cyclin D1 expression in paclitaxel-treated tumors compared to control, suggesting that the neoplastic cells were highly proliferative and nonresponsive to the paclitaxel alone. We have showed for the first time an increase in the efficacy of antineoplastic drugs via the enhancement of gap junctions with PQs, a specific class of gap junction enhancers.
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13
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Brózman O, Novák J, Bauer AK, Babica P. Airborne PAHs inhibit gap junctional intercellular communication and activate MAPKs in human bronchial epithelial cell line. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2020; 79:103422. [PMID: 32492535 PMCID: PMC7486243 DOI: 10.1016/j.etap.2020.103422] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 05/08/2020] [Accepted: 05/20/2020] [Indexed: 06/11/2023]
Abstract
Inhalation exposures to polycyclic aromatic hydrocarbons (PAHs) have been associated with various adverse health effects, including chronic lung diseases and cancer. Using human bronchial epithelial cell line HBE1, we investigated the effects of structurally different PAHs on tissue homeostatic processes, namely gap junctional intercellular communication (GJIC) and MAPKs activity. Rapid (<1 h) and sustained (up to 24 h) inhibition of GJIC was induced by low/middle molecular weight (MW) PAHs, particularly by those with a bay- or bay-like region (1- and 9-methylanthracene, fluoranthene), but also by fluorene and pyrene. In contrast, linear low MW (anthracene, 2-methylanthracene) or higher MW (chrysene) PAHs did not affect GJIC. Fluoranthene, 1- and 9-methylanthracene induced strong and sustained activation of MAPK ERK1/2, whereas MAPK p38 was activated rather nonspecifically by all tested PAHs. Low/middle MW PAHs can disrupt tissue homeostasis in human airway epithelium via structure-dependent nongenotoxic mechanisms, which can contribute to their human health hazards.
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Affiliation(s)
- Ondřej Brózman
- RECETOX, Faculty of Science, Masaryk University, Brno 62500, Czech Republic.
| | - Jiří Novák
- RECETOX, Faculty of Science, Masaryk University, Brno 62500, Czech Republic.
| | - Alison K Bauer
- Department of Environmental and Occupational Health, University of Colorado, Anschutz Medical Center, Aurora, Colorado 80045, USA.
| | - Pavel Babica
- RECETOX, Faculty of Science, Masaryk University, Brno 62500, Czech Republic.
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14
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Targeted Proteomics-Based Quantitative Protein Atlas of Pannexin and Connexin Subtypes in Mouse and Human Tissues and Cancer Cell Lines. J Pharm Sci 2020; 109:1161-1168. [DOI: 10.1016/j.xphs.2019.09.024] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2019] [Revised: 09/29/2019] [Accepted: 09/30/2019] [Indexed: 12/15/2022]
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15
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Connexin 26 and Connexin 43 in Canine Mammary Carcinoma. Vet Sci 2019; 6:vetsci6040101. [PMID: 31818036 PMCID: PMC6958330 DOI: 10.3390/vetsci6040101] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 11/23/2019] [Accepted: 12/01/2019] [Indexed: 12/12/2022] Open
Abstract
Incidence of canine mammary carcinoma is two times higher than the rate of human breast cancer. Mammary tumors are the most common type of cancer in intact female dogs and account for about half of all neoplasms in these dogs. Well-established models of breast cancer have shown that neoplastic cells often have a loss of intercellular communication, particularly gap junction proteins. Thus, the objective of this study is to explore the aspect of gap junction intercellular communication in canine mammary carcinoma, non-cancerous (CMEC) and cancerous (CMT12, CMT27, and CF41.Mg) cells, and patient-derived tumors. Both non-cancerous and cancerous mammary cells express connexins 26 and 43 using immunofluorescence; however, the level of expression is significantly different in quantitative analysis using western blot in which connexin 43 in both CMT12 and CMT27 is significantly decreased compared to CMEC. Furthermore, a decrease of gap junction capacity in CMT12 and CMT27 was observed compared to CMEC. Immunostaining of CMT27-xenograft tumors revealed positive Cx26 and negative Cx43 expression. Similarly, immunostaining of spontaneous canine mammary tumors revealed that Cx26 is present in all tumors while Cx43 is present in 25% of tumors. Overall, the study provides for the first time that a differential pattern of connexin expression exists between non-cancerous and cancerous mammary cells in dogs. This study will pave the path for further in vitro work of connexins in comparative canine models and possibly allow for novel therapeutics to be developed.
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16
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Connexins and Gap Junctions in Cancer of the Urinary Tract. Cancers (Basel) 2019; 11:cancers11050704. [PMID: 31121877 PMCID: PMC6563010 DOI: 10.3390/cancers11050704] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 05/13/2019] [Accepted: 05/20/2019] [Indexed: 12/11/2022] Open
Abstract
This review focuses on connexins and nexus or gap junctions in the genesis, progression, and therapy of carcinomas of the human urinary tract. Some decades ago, the idea was born that gap junctional intercellular communication might prevent both the onset and the progression of cancer. Later evidence indicated that, on the contrary, synthesis and the presence of connexins as a prerequisite for gap junctional intercellular communication might promote the occurrence of cancer and metastases. The research history of urinary bladder cancer is a good example of the development of scientific perception. So far, the role of gap junctional intercellular communication in carcinogenesis and cancer progression, as well as in therapeutical approaches, remains unclear.
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17
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Chasampalioti M, Green AR, Ellis IO, Rakha EA, Jackson AM, Spendlove I, Ramage JM. Connexin 43 is an independent predictor of patient outcome in breast cancer patients. Breast Cancer Res Treat 2019; 174:93-102. [PMID: 30474779 PMCID: PMC6418069 DOI: 10.1007/s10549-018-5063-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 11/16/2018] [Indexed: 01/30/2023]
Abstract
PURPOSE Gap junctions are specialized membrane structures that form channels between adjacent cells allowing cell communication. Gap junctions and specifically Connexin 43 (Cx43) are down-regulated in cancer; however, there are contrasting reports on how this effects breast cancer patient survival. This paper is the first large-scale tissue microarray analysis of Cx43 expression in breast cancer patients with an associated clinical long-term follow-up. METHODS Using a validated TMA of 1118 primary breast cancers, coupled to a comprehensive database of clinicopathological variables, the expression levels and subcellular localisation of Cx43 was assessed by immunohistochemistry. Its impact in terms of survival, distant metastasis-free survival, and clinicopathological variables was determined. RESULTS Patients whose tumors expressed high levels of Cx43 had significantly better survival (p < 0.001) than patients with low levels. High Cx43 expression within tumors was associated with an 18-month survival advantage. Loss of Cx43 expression was associated with markers of poor prognosis, namely large tumor size, high grade, high proliferation status, high pleomorphism, high mitosis, poor Nottingham Prognostic Index (NPI), and triple negative tumors. Cx43 expression was independent of tumor size, grade, stage and ER-status in predicting poor survival on multivariate analysis (p = 0.004). CONCLUSION Connexin 43 (Cx43) is an independent predictor of breast cancer survival and distant metastasis-free survival. High expression of Cx43 was seen in only 13% of tumors, suggesting that drugs to increase Cx43 expression may result in prolonged patients survival.
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Affiliation(s)
- Maria Chasampalioti
- Cancer Immunology Group, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham, UK
| | - Andrew R Green
- Division of Cancer and Stem Cells, Nottingham Breast Cancer Research Centre, School of Medicine, University of Nottingham, Nottingham, UK
| | - Ian O Ellis
- Division of Cancer and Stem Cells, Nottingham Breast Cancer Research Centre, School of Medicine, University of Nottingham, Nottingham, UK
- Department of Pathology, Nottingham University Hospitals NHS Trust, Nottingham City Hospital, Nottingham, UK
| | - Emad A Rakha
- Division of Cancer and Stem Cells, Nottingham Breast Cancer Research Centre, School of Medicine, University of Nottingham, Nottingham, UK
- Department of Pathology, Nottingham University Hospitals NHS Trust, Nottingham City Hospital, Nottingham, UK
| | - Andrew M Jackson
- Host-tumour interactions Group, Division of Cancer and Stem cells, School of Medicine, University of Nottingham, Nottingham, UK
| | - Ian Spendlove
- Cancer Immunology Group, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham, UK
| | - Judith M Ramage
- Cancer Immunology Group, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham, UK.
- Academic Unit of Clinical Oncology, University of Nottingham, Nottingham City Hospital, Nottingham, NG5 1PB, UK.
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18
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Xiao J, Wang X, Wu Y, Zhao Q, Liu X, Zhang G, Zhao Z, Ning Y, Wang K, Tan Y, Du B. Synergistic effect of resveratrol and HSV-TK/GCV therapy on murine hepatoma cells. Cancer Biol Ther 2018; 20:183-191. [PMID: 30257140 PMCID: PMC6343688 DOI: 10.1080/15384047.2018.1523094] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Despite its low transfer efficiency, suicide gene therapy with HSV-TK is known for its bystander killing effect. The connexin-based gap junction is believed to mediate the bystander effect. Recently, we found that resveratrol, a polyphenol compound, increased the expression of Cx26 and Cx43, which are connexins and important constituents of gap junctions, in murine hepatoma cells. Hypothetically, the resveratrol-induced upregulation of gap junctions may improve the bystander effect that HSV-TK/GCV has on hepatoma cells. Our present investigation revealed that resveratrol could enhance intercellular communication at the gap junctions in CBRH7919 hepatoma cells and thereby enhance the bystander killing effect of GCV on CBRH7919TK cells. However, inhibition of gap junction using its long-term inhibitor alpha-glycyrrhetinic acid had a negative influence on the bystander effect of gene therapy with HSV-TK/GCV. In addition, combined resveratrol and GCV treatment in tumor-bearing mice with CBRH7919TK and CBRH7919WT cells at a ratio of 2:3 resulted in a significant decrease in the volume and weight of the tumor in comparison to GCV or only resveratrol. The present results demonstrate that resveratrol can enhance the bystander effect exerted by the HSV-TK/GCV system by enhancing connexin-mediated gap junctional communication.
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Affiliation(s)
- Jianyong Xiao
- a Department of Biochemistry , Guangzhou University of Chinese Medicine , Guangzhou , China.,b Research Center for Integrative Medicine , Guangzhou University of Chinese Medicine , Guangzhou , China
| | - Xiaolan Wang
- a Department of Biochemistry , Guangzhou University of Chinese Medicine , Guangzhou , China
| | - Yingya Wu
- a Department of Biochemistry , Guangzhou University of Chinese Medicine , Guangzhou , China
| | - Qing Zhao
- a Department of Biochemistry , Guangzhou University of Chinese Medicine , Guangzhou , China
| | - Xiaodong Liu
- a Department of Biochemistry , Guangzhou University of Chinese Medicine , Guangzhou , China
| | - Guangxian Zhang
- a Department of Biochemistry , Guangzhou University of Chinese Medicine , Guangzhou , China
| | - Zengqiang Zhao
- a Department of Biochemistry , Guangzhou University of Chinese Medicine , Guangzhou , China
| | - Yizhen Ning
- a Department of Biochemistry , Guangzhou University of Chinese Medicine , Guangzhou , China
| | - Kun Wang
- c Department of Pathology , Guangzhou University of Chinese Medicine , Guangzhou , China
| | - Yuhui Tan
- a Department of Biochemistry , Guangzhou University of Chinese Medicine , Guangzhou , China
| | - Biaoyan Du
- c Department of Pathology , Guangzhou University of Chinese Medicine , Guangzhou , China
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19
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Zhang Q, Wu S, Liu L, Hou X, Jiang J, Wei X, Hao W. Effects of bisphenol A on gap junctions in HaCaT cells as mediated by the estrogen receptor pathway. J Appl Toxicol 2018; 39:271-281. [DOI: 10.1002/jat.3717] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 07/11/2018] [Accepted: 07/25/2018] [Indexed: 12/23/2022]
Affiliation(s)
- Qi Zhang
- Department of Toxicology, School of Public Health; Peking University, Beijing Key Laboratory of Toxicological Research and Risk Assessment for Food Safety; Beijing 100191 China
| | - Shuang Wu
- Department of Toxicology, School of Public Health; Peking University, Beijing Key Laboratory of Toxicological Research and Risk Assessment for Food Safety; Beijing 100191 China
| | - Lu Liu
- Department of Genetics, School of Basic Medical Science; Peking University; Beijing 100191 China
| | - Xiaohong Hou
- Department of Toxicology, School of Public Health; Peking University, Beijing Key Laboratory of Toxicological Research and Risk Assessment for Food Safety; Beijing 100191 China
| | - Jianjun Jiang
- Department of Toxicology, School of Public Health; Peking University, Beijing Key Laboratory of Toxicological Research and Risk Assessment for Food Safety; Beijing 100191 China
| | - Xuetao Wei
- Department of Toxicology, School of Public Health; Peking University, Beijing Key Laboratory of Toxicological Research and Risk Assessment for Food Safety; Beijing 100191 China
| | - Weidong Hao
- Department of Toxicology, School of Public Health; Peking University, Beijing Key Laboratory of Toxicological Research and Risk Assessment for Food Safety; Beijing 100191 China
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20
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Thiagarajan PS, Sinyuk M, Turaga SM, Mulkearns-Hubert EE, Hale JS, Rao V, Demelash A, Saygin C, China A, Alban TJ, Hitomi M, Torre-Healy LA, Alvarado AG, Jarrar A, Wiechert A, Adorno-Cruz V, Fox PL, Calhoun BC, Guan JL, Liu H, Reizes O, Lathia JD. Cx26 drives self-renewal in triple-negative breast cancer via interaction with NANOG and focal adhesion kinase. Nat Commun 2018; 9:578. [PMID: 29422613 PMCID: PMC5805730 DOI: 10.1038/s41467-018-02938-1] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 01/09/2018] [Indexed: 12/18/2022] Open
Abstract
Tumors adapt their phenotypes during growth and in response to therapies through dynamic changes in cellular processes. Connexin proteins enable such dynamic changes during development, and their dysregulation leads to disease states. The gap junction communication channels formed by connexins have been reported to exhibit tumor-suppressive functions, including in triple-negative breast cancer (TNBC). However, we find that connexin 26 (Cx26) is elevated in self-renewing cancer stem cells (CSCs) and is necessary and sufficient for their maintenance. Cx26 promotes CSC self-renewal by forming a signaling complex with the pluripotency transcription factor NANOG and focal adhesion kinase (FAK), resulting in NANOG stabilization and FAK activation. This FAK/NANOG-containing complex is not formed in mammary epithelial or luminal breast cancer cells. These findings challenge the paradigm that connexins are tumor suppressors in TNBC and reveal a unique function for Cx26 in regulating the core self-renewal signaling that controls CSC maintenance. Connexin proteins are usually considered as tumor suppressors. Here, the authors show that connexin 26 (Cx26) regulates the self-renewal of breast cancer stem cells via a ternary complex with FAK and NANOG.
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Affiliation(s)
- Praveena S Thiagarajan
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA.,Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA
| | - Maksim Sinyuk
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Soumya M Turaga
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Erin E Mulkearns-Hubert
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - James S Hale
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Vinay Rao
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Abeba Demelash
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Caner Saygin
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Arnab China
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Tyler J Alban
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA.,Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA
| | - Masahiro Hitomi
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA.,Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA
| | - Luke A Torre-Healy
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Alvaro G Alvarado
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Awad Jarrar
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Andrew Wiechert
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA
| | - Valery Adorno-Cruz
- Case Comprehensive Cancer Center, Cleveland, OH, 44195, USA.,Department of Pathology, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA.,Departments of Pharmacology and Medicine, Northwestern University School of Medicine, Chicago, IL, 60611, USA
| | - Paul L Fox
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA.,Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA.,Case Comprehensive Cancer Center, Cleveland, OH, 44195, USA
| | | | - Jun-Lin Guan
- Department of Cancer Biology, University of Cincinnati, Cincinnati, OH, 45267, USA
| | - Huiping Liu
- Case Comprehensive Cancer Center, Cleveland, OH, 44195, USA.,Department of Pathology, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA.,Departments of Pharmacology and Medicine, Northwestern University School of Medicine, Chicago, IL, 60611, USA
| | - Ofer Reizes
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA. .,Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA. .,Case Comprehensive Cancer Center, Cleveland, OH, 44195, USA.
| | - Justin D Lathia
- Department of Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, 44915, USA. .,Molecular Medicine, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA. .,Case Comprehensive Cancer Center, Cleveland, OH, 44195, USA.
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21
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Agrahari AK, Kumar A, R S, Zayed H, C GPD. Substitution impact of highly conserved arginine residue at position 75 in GJB1 gene in association with X-linked Charcot-Marie-tooth disease: A computational study. J Theor Biol 2018; 437:305-317. [PMID: 29111421 DOI: 10.1016/j.jtbi.2017.10.028] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 10/23/2017] [Accepted: 10/26/2017] [Indexed: 10/18/2022]
Abstract
X-linked Charcot-Marie-Tooth type 1 X (CMTX1) disease is a subtype of Charcot-Marie-Tooth (CMT), which is mainly caused by mutations in the GJB1 gene. It is also known as connexin 32 (Cx32) that leads to Schwann cell abnormalities and peripheral neuropathy. CMTX1 is considered as the second most common form of CMT disease. The aim of this study is to computationally predict the potential impact of different single amino acid substitutions at position 75 of Cx32, from arginine (R) to proline (P), glutamine (Q) and tryptophan (W). This position is known to be highly conserved among the family of connexin. To understand the structural and functional changes due to these single amino acid substitutions, we employed a homology-modeling technique to build the three-dimensional structure models for the native and mutant proteins. The protein structures were further embedded into a POPC lipid bilayer, inserted into a water box, and subjected to molecular dynamics simulation for 50 ns. Our results show that the mutants R75P, R75Q and R75W display variable structural conformation and dynamic behavior compared to the native protein. Our data proves useful in predicting the potential pathogenicity of the mutant proteins and is expected to serve as a platform for drug discovery for patients with CMT.
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Affiliation(s)
| | - Amit Kumar
- Department of Mechanical, Chemical and Materials Engineering, University of Cagliari, via Marengo 2, 09123 Cagliari, Italy; Biosciences Sector, Center for advanced study research and development in Sardinia (CRS4), Loc. Piscina Manna, 09010 Pula, Italy
| | - Siva R
- School of Biosciences and Technology, VIT University, Vellore, Tamil Nadu, India
| | - Hatem Zayed
- Department of Biomedical Sciences, College of Health and Sciences, Qatar University, Doha, Qatar
| | - George Priya Doss C
- School of Biosciences and Technology, VIT University, Vellore, Tamil Nadu, India.
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22
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Yu M, Zou Q, Wu X, Han G, Tong X. Connexin 32 affects doxorubicin resistance in hepatocellular carcinoma cells mediated by Src/FAK signaling pathway. Biomed Pharmacother 2017; 95:1844-1852. [PMID: 28968929 DOI: 10.1016/j.biopha.2017.09.065] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 09/07/2017] [Accepted: 09/13/2017] [Indexed: 12/31/2022] Open
Abstract
Doxorubicin (DOX) is first-line chemotherapy for hepatocellular carcinoma (HCC), but the effect is not satisfactory. The resistance of HCC cells to DOX is the main reason leading to treatment failure. Therefore, it is necessary to study the mechanism of DOX resistance in HCC. In this study, expression of connexin (Cx)32 was significantly decreased in HCC tissues compared with corresponding paracancerous tissues, and activity of the Src/focal adhesion kinase (FAK) signaling pathway was significantly enhanced. Expression of Cx32 was closely associated with activity of the Src/FAK signaling pathway, Cx32, and the Src/FAK signaling pathway was also correlated with degree of HCC differentiation. In DOX-resistant HepG2 cells, compared with DOX-sensitive HepG2 cells, expression of Cx32 was significantly reduced and activity of the Src/FAK pathway increased. After silencing Cx32 in HepG2 cells, activity of the Src/FAK pathway increased and sensitivity to DOX decreased. In contrast, overexpression of Cx32 in HepG2/DOX cells decreased activity of the Src/FAK pathway and increased sensitivity to DOX. Dasatinib and KX2-391, inhibitors of the Src/FAK pathway, significantly increased the sensitivity of HepG2/DOX cells to DOX. The results suggest that Src/FAK is a downstream regulator of Cx32 and Cx32 regulates the sensitivity of HCC cells to DOX via the Src/FAK signaling pathway. Our study demonstrates a potential mechanism of DOX resistance in HCC cells and supports that Cx32-Src/FAK is an important target for reversing drug resistance of HCC.
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Affiliation(s)
- Meiling Yu
- Department of Pharmacy, the First Affiliated Hospital of Bengbu Medical College, Anhui, Bengbu, 233004, PR China
| | - Qi Zou
- Department of Critical Care Medicine, the First Affiliated Hospital of Bengbu Medical College, Anhui, Bengbu, 233004, PR China
| | - Xiaoxiang Wu
- Department of Pharmacy, the Second Affiliated Hospital of Bengbu Medical College, Anhui, Bengbu, 233004, PR China
| | - Guangshu Han
- Faculty of Pharmacy, Bengbu Medical College, Anhui, Bengbu, 233030, PR China
| | - Xuhui Tong
- Faculty of Pharmacy, Bengbu Medical College, Anhui, Bengbu, 233030, PR China.
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23
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Phillips SL, Williams CB, Zambrano JN, Williams CJ, Yeh ES. Connexin 43 in the development and progression of breast cancer: What's the connection? (Review). Int J Oncol 2017; 51:1005-1013. [PMID: 28902343 PMCID: PMC5592860 DOI: 10.3892/ijo.2017.4114] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 07/17/2017] [Indexed: 12/20/2022] Open
Abstract
Connexin 43 is a prominent gap junction protein within normal human breast tissue. Thus far, there have been a number of research studies performed to determine the function of connexin 43 in breast tumor formation and progression. Within primary tumors, research suggests that the level of connexin 43 expression in breast tumors is altered when compared to normal human breast tissue. While some reports indicate that connexin 43 levels decrease, other evidence suggests that connexin 43 levels are increased and protein localization shifts from the plasma membrane to the cytoplasm. In either case, the prevailing theory is that breast tumor cells have reduced gap junction intercellular communication within primary tumors. The current consensus appears to be that the loss of connexin 43 gap junction intercellular communication is an early event in malignancy, with the possibility of gap junction restoration in the event of metastasis. However, additional evidence is needed to support the latter claim. The purpose of this report is to review the connexin 43 literature that describes studies using human tissue samples, in order to evaluate the function of connexin 43 protein in normal human breast tissue as well as the role of connexin 43 in human breast tumor formation and metastatic progression.
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Affiliation(s)
- Stephanie L Phillips
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Medical University of South Carolina, Charleston, SC, USA
| | - Carly Bess Williams
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, SC, USA
| | - Joelle N Zambrano
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, SC, USA
| | - Christina J Williams
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, SC, USA
| | - Elizabeth S Yeh
- Department of Cell and Molecular Pharmacology and Experimental Therapeutics, Medical University of South Carolina, Charleston, SC, USA
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24
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Wong P, Laxton V, Srivastava S, Chan YWF, Tse G. The role of gap junctions in inflammatory and neoplastic disorders (Review). Int J Mol Med 2017; 39:498-506. [PMID: 28098880 PMCID: PMC5360388 DOI: 10.3892/ijmm.2017.2859] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 12/23/2016] [Indexed: 12/29/2022] Open
Abstract
Gap junctions are intercellular channels made of connexin proteins, mediating both electrical and biochemical signals between cells. The ability of gap junction proteins to regulate immune responses, cell proliferation, migration, apoptosis and carcinogenesis makes them attractive therapeutic targets for treating inflammatory and neoplastic disorders in different organ systems. Alterations in gap junction profile and expression levels are observed in hyperproliferative skin disorders, lymphatic vessel diseases, inflammatory lung diseases, liver injury and neoplastic disorders. It is now recognized that the therapeutic effects mediated by traditional pharmacological agents are dependent upon gap junction communication and may even act by influencing gap junction expression or function. Novel strategies for modulating the function or expression of connexins, such as the use of synthetic mimetic peptides and siRNA technology are considered.
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Affiliation(s)
- Pui Wong
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, SAR, P.R. China
| | - Victoria Laxton
- Intensive Care Department, Royal Brompton and Harefield NHS Foundation Trust, London SW3 6NP
| | | | - Yin Wah Fiona Chan
- School of Biological Sciences, University of Cambridge, Cambridge CB2 1AG, UK
| | - Gary Tse
- Department of Medicine and Therapeutics
- Li Ka Shing Institute of Health Sciences, Faculty of Medicine, Chinese University of Hong Kong, Hong Kong, SAR, P.R. China
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25
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Sahu A, Ghosh R, Deshpande G, Prasad M. A Gap Junction Protein, Inx2, Modulates Calcium Flux to Specify Border Cell Fate during Drosophila oogenesis. PLoS Genet 2017; 13:e1006542. [PMID: 28114410 PMCID: PMC5256874 DOI: 10.1371/journal.pgen.1006542] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 12/15/2016] [Indexed: 01/09/2023] Open
Abstract
Intercellular communication mediated by gap junction (GJ) proteins is indispensable during embryogenesis, tissue regeneration and wound healing. Here we report functional analysis of a gap junction protein, Innexin 2 (Inx2), in cell type specification during Drosophila oogenesis. Our data reveal a novel involvement of Inx2 in the specification of Border Cells (BCs), a migratory cell type, whose identity is determined by the cell autonomous STAT activity. We show that Inx2 influences BC fate specification by modulating STAT activity via Domeless receptor endocytosis. Furthermore, detailed experimental analysis has uncovered that Inx2 also regulates a calcium flux that transmits across the follicle cells. We propose that Inx2 mediated calcium flux in the follicle cells stimulates endocytosis by altering Dynamin (Shibire) distribution which is in turn critical for careful calibration of STAT activation and, thus for BC specification. Together our data provide unprecedented molecular insights into how gap junction proteins can regulate cell-type specification. Gap junction mediated intercellular communication modulates several processes during development, morphogenesis and normal tissue homeostasis. While gap junction proteins play an important role during intercellular communication, the underlying molecular mechanism(s) as to how they regulate diverse signaling cascades are unclear. By employing the Drosophila melanogaster oogenesis model we have characterized the role of gap junction protein, Innexin 2 (Inx2), in cell fate specification during Drosophila oogenesis. Our data demonstrate that loss of inx2 affects border cell specification. Border cells are a small group of 6–8 follicle cells that acquire migratory fate in response to the activation of JAK-STAT signaling. We show that perturbing Inx2 levels in the follicle cells inhibits JAK-STAT signaling thereby adversely influencing border cell fate specification. Using live cell imaging and molecular genetic analysis, we have elucidated the molecular mechanism underlying Inx2 function in this process. We show that Inx2 mediates inter-follicular calcium flux that is critical for border cell fate determination. Furthermore, our observations indicate that Inx2 regulates Domeless receptor internalization possibly via influencing distribution of Drosophila Dynamin, Shibire in the follicle cells. Taken together these results suggest a functional link between Inx2, calcium flux and receptor endocytosis during border cell fate specification in Drosophila oogenesis.
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Affiliation(s)
- Aresh Sahu
- Department of Biological Sciences Indian Institute of Science Education & Research Kolkata Mohanpur Campus Mohanpur, Nadia, West Bengal, India
| | - Ritabrata Ghosh
- Department of Biological Sciences Indian Institute of Science Education & Research Kolkata Mohanpur Campus Mohanpur, Nadia, West Bengal, India
| | - Girish Deshpande
- Department of Molecular Biology Princeton University, Princeton, NJ, United States of America
- Indian Institute of Science Education and Research Pune. Pune Maharashtra, India
| | - Mohit Prasad
- Department of Biological Sciences Indian Institute of Science Education & Research Kolkata Mohanpur Campus Mohanpur, Nadia, West Bengal, India
- * E-mail:
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26
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Wong P, Tan T, Chan C, Laxton V, Chan YWF, Liu T, Wong WT, Tse G. The Role of Connexins in Wound Healing and Repair: Novel Therapeutic Approaches. Front Physiol 2016; 7:596. [PMID: 27999549 PMCID: PMC5138227 DOI: 10.3389/fphys.2016.00596] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 11/16/2016] [Indexed: 12/26/2022] Open
Abstract
Gap junctions are intercellular proteins responsible for mediating both electrical and biochemical coupling through the exchange of ions, second messengers and small metabolites. They consist of two connexons, with (one) connexon supplied by each cell. A connexon is a hexamer of connexins and currently more than 20 connexin isoforms have been described in the literature thus far. Connexins have a short half-life, and therefore gap junction remodeling constantly occurs with a high turnover rate. Post-translational modification, such as phosphorylation, can modify their channel activities. In this article, the roles of connexins in wound healing and repair are reviewed. Novel strategies for modulating the function or expression of connexins, such as the use of antisense technology, synthetic mimetic peptides and bioactive materials for the treatment of skin wounds, diabetic and pressure ulcers as well as cornea wounds, are considered.
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Affiliation(s)
- Pui Wong
- Li Ka Shing Faculty of Medicine, School of Biomedical Sciences, University of Hong Kong Hong Kong, Hong Kong
| | - Teresa Tan
- Department of Surgery, Faculty of Medicine, Chinese University of Hong Kong Hong Kong, Hong Kong
| | - Catherine Chan
- Department of Surgery, Faculty of Medicine, Chinese University of Hong Kong Hong Kong, Hong Kong
| | - Victoria Laxton
- Intensive Care Department, Royal Brompton and Harefield NHS Foundation Trust London, UK
| | - Yin Wah Fiona Chan
- Department of Psychology, School of Biological Sciences, University of Cambridge Cambridge, UK
| | - Tong Liu
- Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University Tianjin, China
| | - Wing Tak Wong
- School of Life Sciences, Chinese University of Hong Kong Hong Kong, Hong Kong
| | - Gary Tse
- Department of Medicine and Therapeutics, Faculty of Medicine, Chinese University of Hong KongHong Kong, Hong Kong; Faculty of Medicine, Li Ka Shing Institute of Health Sciences, Chinese University of Hong KongHong Kong, Hong Kong
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27
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Cx26 knockout predisposes the mammary gland to primary mammary tumors in a DMBA-induced mouse model of breast cancer. Oncotarget 2016; 6:37185-99. [PMID: 26439696 PMCID: PMC4741923 DOI: 10.18632/oncotarget.5953] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 09/17/2015] [Indexed: 11/28/2022] Open
Abstract
Down-regulation of the gap junction protein connexin26 (Cx26) is an early event following breast cancer onset and has led to Cx26 being classically described as a tumor suppressor. Interestingly, mutations in theCx26 gene (GJB2) reduce or ablate Cx26 gap junction channel function and are the most common cause of genetic deafness. It is unknown if patients with loss-of-function GJB2 mutations have a greater susceptibility to breast tumorigenesis or aggressive breast cancer progression. To investigate these possibilities, 7, 12-dimethylbenz[α]anthracene (DMBA)-induced tumor development was evaluated in BLG-Cre; Cx26fl/fl mice expressing Cre under the β-Lactoglobulin promoter (Cre+) compared to Cx26fl/fl controlmice (Cre-) following pituitary isograft driven Cx26 knockout. A significantly increased number of DMBA-treated Cre+ mice developed primary mammary tumors, as well as developed multiple tumors, compared to Cre- mice. Primary tumors of Cre+ mice were of multiple histological subtypes and had similar palpable tumour onset and growth rate compared to tumors from Cre- mice. Lungs were evaluated for evidence of metastases revealing a similar percentage of lung metastases in Cre+ and Cre- mice. Together, our results suggest that loss of Cx26 predisposes the mammary gland to chemically induced mammary tumour formation which may have important implications to patients with GJB2 mutations.
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28
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Affiliation(s)
- Janet Andersen
- Departments of Obstetrics and Gynecology and Reproductive Medicine, State University of New York at Stony Brook, Stony Brook, New York; Department of Obstetrics and Gynecology, Harvard Medical School, Boston, Massachusetts
| | - Robert L. Barbieri
- Department of Obstetrics and Gynecology, School of Medicine, SUNY at Stony Brook, Stony Brook, NY 11794-8091; Departments of Obstetrics and Gynecology and Reproductive Medicine, State University of New York at Stony Brook, Stony Brook, New York; Department of Obstetrics and Gynecology, Harvard Medical School, Boston, Massachusetts
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29
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Connexin's Connection in Breast Cancer Growth and Progression. Int J Cell Biol 2016; 2016:9025905. [PMID: 27642298 PMCID: PMC5011527 DOI: 10.1155/2016/9025905] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 07/18/2016] [Indexed: 12/26/2022] Open
Abstract
Gap junctions are cell-to-cell junctions that are located in the basolateral surface of two adjoining cells. A gap junction channel is composed of a family of proteins called connexins. Gap junction channels maintain intercellular communication between two cells through the exchange of ions, small metabolites, and electrical signals. Gap junction channels or connexins are widespread in terms of their expression and function in maintaining the development, differentiation, and homeostasis of vertebrate tissues. Gap junction connexins play a major role in maintaining intercellular communication among different cell types of normal mammary gland for proper development and homeostasis. Connexins have also been implicated in the pathogenesis of breast cancer. Differential expression pattern of connexins and their gap junction dependent or independent functions provide pivotal cross talk of breast tumor cells with the surrounding stromal cell in the microenvironment. Substantial research from the last 20 years has accumulated ample evidences that allow us a better understanding of the roles that connexins play in the tumorigenesis of primary breast tumor and its metastatic progression. This review will summarize the knowledge about the connexins and gap junction activities in breast cancer highlighting the differential expression and functional dynamics of connexins in the pathogenesis of the disease.
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30
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Connexin 43, breast cancer tumor suppressor: Missed connections? Cancer Lett 2016; 374:117-126. [DOI: 10.1016/j.canlet.2016.02.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 01/28/2016] [Accepted: 02/03/2016] [Indexed: 12/21/2022]
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31
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Poyet C, Buser L, Roudnicky F, Detmar M, Hermanns T, Mannhard D, Höhn A, Rüschoff J, Zhong Q, Sulser T, Moch H, Wild PJ. Connexin 43 expression predicts poor progression-free survival in patients with non-muscle invasive urothelial bladder cancer. J Clin Pathol 2015; 68:819-24. [PMID: 26251520 PMCID: PMC4602233 DOI: 10.1136/jclinpath-2015-202898] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Accepted: 05/25/2015] [Indexed: 12/05/2022]
Abstract
Objectives To evaluate the protein expression of connexin 43 (Cx43) in primary urothelial bladder cancer and test its association with the histopathological characteristics and clinical outcome. Methods A tissue microarray containing 348 tissue samples from 174 patients with primary urothelial carcinomas of the bladder was immunohistochemically stained for Cx43. The intensity of staining was semiquantitatively evaluated (score 0, 1+, 2+), and the association with clinicopathological features was assessed. Univariable and multivariable analyses were performed to identify predictors for progression-free survival (PFS). Results Membranous Cx43 immunoreactivity was detected in 118 (67.8%) of 174 analysable urothelial carcinomas, of which 31 (17.8%) showed even a strong (score 2+) and mainly homogeneous staining. Strong expression levels of Cx43 (score 2+) were associated with higher tumour grade, multiplicity and increased proliferation (all p<0.05). In the subgroup of patients with stage pTa and pT1 bladder tumours (n=158), strong Cx43 expression (p<0.001), solid growth pattern (p<0.001) and increased Ki-67 proliferation fraction (p<0.05) were significantly associated with shorter PFS in an univariable Cox regression analysis. In multivariable Cox regression models, Cx43 immunoreactivity and histological growth pattern remained highly significant and adverse risk factors for PFS. Conclusions The expression levels of Cx43 are frequent in non-muscle invasive bladder cancer (NMIBC), with high expression levels being associated with poor prognosis. Routine assessment of Cx43 expression may improve the identification of high-risk NMIBC.
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Affiliation(s)
- Cédric Poyet
- Department of Urology, University Hospital Zurich, Zurich, Switzerland
| | - Lorenz Buser
- Institute of Surgical Pathology, University Hospital Zurich, Zurich, Switzerland
| | - Filip Roudnicky
- Institute of Pharmaceutical Sciences, ETH Zurich, Zurich, Switzerland
| | - Michael Detmar
- Institute of Pharmaceutical Sciences, ETH Zurich, Zurich, Switzerland
| | - Thomas Hermanns
- Department of Urology, University Hospital Zurich, Zurich, Switzerland
| | - Doris Mannhard
- Department of Urology, University Hospital Zurich, Zurich, Switzerland
| | - Andrej Höhn
- Department of Urology, University Hospital Zurich, Zurich, Switzerland
| | - Jan Rüschoff
- Institute of Surgical Pathology, University Hospital Zurich, Zurich, Switzerland
| | - Qing Zhong
- Institute of Surgical Pathology, University Hospital Zurich, Zurich, Switzerland
| | - Tullio Sulser
- Department of Urology, University Hospital Zurich, Zurich, Switzerland
| | - Holger Moch
- Institute of Surgical Pathology, University Hospital Zurich, Zurich, Switzerland
| | - Peter J Wild
- Institute of Surgical Pathology, University Hospital Zurich, Zurich, Switzerland
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32
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Murayama T, Maruyama IN. Alkaline pH sensor molecules. J Neurosci Res 2015; 93:1623-30. [PMID: 26154399 DOI: 10.1002/jnr.23621] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Revised: 06/12/2015] [Accepted: 06/26/2015] [Indexed: 12/22/2022]
Abstract
Animals can survive only within a narrow pH range. This requires continual monitoring of environmental and body-fluid pH. Although a variety of acidic pH sensor molecules have been reported, alkaline pH sensor function is not well understood. This Review describes neuronal alkaline pH sensors, grouped according to whether they monitor extracellular or intracellular alkaline pH. Extracellular sensors include the receptor-type guanylyl cyclase, the insulin receptor-related receptor, ligand-gated Cl- channels, connexin hemichannels, two-pore-domain K+ channels, and transient receptor potential (TRP) channels. Intracellular sensors include TRP channels and gap junction channels. Identification of molecular mechanisms underlying alkaline pH sensing is crucial for understanding how animals respond to environmental alkaline pH and how body-fluid pH is maintained within a narrow range.
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Affiliation(s)
- Takashi Murayama
- Information Processing Biology Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Ichiro N Maruyama
- Information Processing Biology Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
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33
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Stewart MKG, Simek J, Laird DW. Insights into the role of connexins in mammary gland morphogenesis and function. Reproduction 2015; 149:R279-90. [DOI: 10.1530/rep-14-0661] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 03/19/2015] [Indexed: 12/15/2022]
Abstract
Gap junctions formed of connexin subunits link adjacent cells by direct intercellular communication that is essential for normal tissue homeostasis in the mammary gland. The mammary gland undergoes immense remodeling and requires exquisite regulation to control the proliferative, differentiating, and cell death mechanisms regulating gland development and function. The generation of novel genetically modified mice with reduced or ablated connexin function within the mammary gland has advanced our understanding of the role of gap junctions during the complex and dynamic process of mammary gland development. These studies have revealed an important stage-specific role for Cx26 (GJA1) and Cx43 (GJB2), while Cx30 (GJB6) and Cx32 (Gjb1) can be eliminated without compromising the gland. Yet, there remain gaps in our understanding of the role of mammary gland gap junctions.
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34
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Lübkemeier I, Bosen F, Kim JS, Sasse P, Malan D, Fleischmann BK, Willecke K. Human Connexin43E42K Mutation From a Sudden Infant Death Victim Leads to Impaired Ventricular Activation and Neonatal Death in Mice. ACTA ACUST UNITED AC 2015; 8:21-9. [DOI: 10.1161/circgenetics.114.000793] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background—
Sudden infant death syndrome (SIDS) describes the sudden, unexplained death of a baby during its first year of age and is the third leading cause of infant mortality. It is assumed that ≤20% of all SIDS cases are because of cardiac arrhythmias resulting from mutations in ion channel proteins. Besides ion channels also cardiac gap junction channels are important for proper conduction of cardiac electric activation. In the mammalian heart Connexin43 (Cx43) is the major gap junction protein expressed in ventricular cardiomyocytes. Recently, a novel Connexin43 loss-of-function mutation (Cx43E42K) was identified in a 2-month-old SIDS victim.
Methods and Results—
We have generated Cx43E42K-expressing mice as a model for SIDS. Heterozygous cardiac-restricted Cx43E42K-mutated mice die neonatally without major cardiac morphological defects. Electrocardiographic recordings of embryonic Cx43+/E42K mice reveal severely disturbed ventricular activation, whereas immunohistochemical analyses show normal localization and expression patterns of gap junctional Connexin43 protein in the Cx43E42K-mutated newborn mouse heart.
Conclusions—
Because we did not find heterogeneous gap junction loss in Cx43E42K mouse hearts, we conclude that the Cx43E42K gap junction channel creates an arrhythmogenic substrate leading to lethal ventricular arrhythmias. The strong cardiac phenotype of Cx43E42K expressing mice supports the association between the human Cx43E42K mutation and SIDS and indicates that Connexin43 mutations should be considered in future studies when SIDS cases are to be molecularly explained.
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Affiliation(s)
- Indra Lübkemeier
- From the Life and Medical Sciences (LIMES) Institute, Molecular Genetics (I.L., F.B., K.W.) and Institute of Physiology I, Life and Brain Center (P.S., D.M., B.K.F.), University of Bonn, Bonn, Germany; and Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea (J.-S.K.)
| | - Felicitas Bosen
- From the Life and Medical Sciences (LIMES) Institute, Molecular Genetics (I.L., F.B., K.W.) and Institute of Physiology I, Life and Brain Center (P.S., D.M., B.K.F.), University of Bonn, Bonn, Germany; and Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea (J.-S.K.)
| | - Jung-Sun Kim
- From the Life and Medical Sciences (LIMES) Institute, Molecular Genetics (I.L., F.B., K.W.) and Institute of Physiology I, Life and Brain Center (P.S., D.M., B.K.F.), University of Bonn, Bonn, Germany; and Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea (J.-S.K.)
| | - Philipp Sasse
- From the Life and Medical Sciences (LIMES) Institute, Molecular Genetics (I.L., F.B., K.W.) and Institute of Physiology I, Life and Brain Center (P.S., D.M., B.K.F.), University of Bonn, Bonn, Germany; and Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea (J.-S.K.)
| | - Daniela Malan
- From the Life and Medical Sciences (LIMES) Institute, Molecular Genetics (I.L., F.B., K.W.) and Institute of Physiology I, Life and Brain Center (P.S., D.M., B.K.F.), University of Bonn, Bonn, Germany; and Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea (J.-S.K.)
| | - Bernd K. Fleischmann
- From the Life and Medical Sciences (LIMES) Institute, Molecular Genetics (I.L., F.B., K.W.) and Institute of Physiology I, Life and Brain Center (P.S., D.M., B.K.F.), University of Bonn, Bonn, Germany; and Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea (J.-S.K.)
| | - Klaus Willecke
- From the Life and Medical Sciences (LIMES) Institute, Molecular Genetics (I.L., F.B., K.W.) and Institute of Physiology I, Life and Brain Center (P.S., D.M., B.K.F.), University of Bonn, Bonn, Germany; and Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea (J.-S.K.)
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Qin Y, Mohandessi S, Gordon L, Wadehra M. Regulation of FAK Activity by Tetraspan Proteins: Potential Clinical Implications in Cancer. Crit Rev Oncog 2015; 20:391-405. [PMID: 27279237 PMCID: PMC5390008 DOI: 10.1615/critrevoncog.v20.i5-6.110] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that regulates multiple cell signaling pathways in both physiological and pathological conditions. Overexpression and activation of FAK is associated with many advanced stage cancers through promoting cancer cell tumorigenicity and progression as well as by regulating the tumor microenvironment. FAK has multiple binding partners through which FAK exerts its functions including RhoGEF, Src family, talin, cortactin, and paxilin. Over the last few years, it has been proposed that a novel group of four transmembrane proteins can interact with FAK and regulate its activity. These include select tetraspanins such as CD151 and CD9 as well as the GAS3 family members epithelial membrane protein-2 (EMP2) and peripheral myelin protein-22 (PMP22). In this review, we discuss the current knowledge of the interaction between FAK and tetraspan proteins in physiological and pathological conditions, with an emphasis on the potential of tetraspan family members as therapeutic targets in cancer.
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Affiliation(s)
- Yu Qin
- Department of Ophthalmology, Jules Stein Eye Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Shabnam Mohandessi
- Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Lynn Gordon
- Department of Ophthalmology, Jules Stein Eye Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA
| | - Madhuri Wadehra
- Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA
- Jonsson Comprehensive Cancer Center, David Geffen School of Medicine at UCLA, Los Angeles, CA
- Center to Eliminate Cancer Health Disparities, Charles Drew University, Los Angeles, CA
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Aasen T. Connexins: junctional and non-junctional modulators of proliferation. Cell Tissue Res 2014; 360:685-99. [PMID: 25547217 DOI: 10.1007/s00441-014-2078-3] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2014] [Accepted: 11/14/2014] [Indexed: 12/11/2022]
Abstract
Mounting evidence indicates that dysregulation of gap junctions and their structural subunits-connexins-often occurs in, and sometimes causes, a variety of proliferative disorders, including cancer. Connexin-mediated regulation of cell proliferation is complex and may involve modulation of gap junction intercellular communication (GJIC), hemichannel signalling, or gap junction-independent paths. However, the exact mechanisms linking connexins to proliferation remain poorly defined and a number of contradictory studies report both pro- and anti-proliferative effects, effects that often depend on the cell or tissue type or the microenvironment. The present review covers junctional and non-junctional regulation of proliferation by connexins, with a particular emphasis on their association with cancer.
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Affiliation(s)
- Trond Aasen
- Molecular Pathology Group, Vall d'Hebron Institut de Recerca (VHIR), Universitat Autònoma de Barcelona, Passeig Vall d'Hebron 119-129, Barcelona, 08035, Spain,
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Abstract
SUMMARY Melanoma cells interact with and depend on seemingly normal cells in their tumour microenvironment to allow the acquisition of the hallmarks of solid cancer. In general, there are three types of interaction of melanoma cells with their microenvironment. First, there is bilateral communication between melanoma cells and the stroma, which includes fibroblasts, endothelial cells, immune cells, soluble molecules, and the extracellular matrix. Second, while under normal conditions keratinocytes control localisation and proliferative behaviour of melanocytes in the epidermis, once this balance is disturbed and a melanoma has developed, melanoma cells may take over the control of their epidermal tumour microenvironment. Finally, there are subcompartments within tumours with different microenvironmental milieu defined by their access to oxygen and nutrients. Therefore, different melanoma cells within a tumour face different microenvironments. Interactions between melanoma cells among each other and with the cell types in their microenvironment happen through endocrine and paracrine communication and/or through direct contact via cell-cell and cell-matrix adhesion, and gap junctional intercellular communication (GJIC). Connexins have been identified as key molecules for direct cell-cell communication and are also thought to be important for the release of signalling molecules from cells to the microenvironment. In this review we provide an update of the alterations in cell-cell communication in melanoma and the tumour microenvironment associated with melanoma development and progression.
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Lübkemeier I, Andrié R, Lickfett L, Bosen F, Stöckigt F, Dobrowolski R, Draffehn AM, Fregeac J, Schultze JL, Bukauskas FF, Schrickel JW, Willecke K. The Connexin40A96S mutation from a patient with atrial fibrillation causes decreased atrial conduction velocities and sustained episodes of induced atrial fibrillation in mice. J Mol Cell Cardiol 2013; 65:19-32. [PMID: 24060583 DOI: 10.1016/j.yjmcc.2013.09.008] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 09/11/2013] [Accepted: 09/13/2013] [Indexed: 12/22/2022]
Abstract
Atrial fibrillation (AF) is the most common type of cardiac arrhythmia and a major cause of stroke. In the mammalian heart the gap junction proteins connexin40 (Cx40) and connexin43 (Cx43) are strongly expressed in the atrial myocardium mediating effective propagation of electrical impulses. Different heterozygous mutations in the coding region for Cx40 were identified in patients with AF. We have generated transgenic Cx40A96S mice harboring one of these mutations, the loss-of-function Cx40A96S mutation, as a model for atrial fibrillation. Cx40A96S mice were characterized by immunochemical and electrophysiological analyses. Significantly reduced atrial conduction velocities and strongly prolonged episodes of atrial fibrillation were found after induction in Cx40A96S mice. Analyses of the gating properties of Cx40A96S channels in cultured HeLa cells also revealed significantly lower junctional conductance and enhanced sensitivity voltage gating of Cx40A96S in comparison to Cx40 wild-type gap junctions. This is caused by reduced open probabilities of Cx40A96S gap junction channels, while single channel conductance remained the same. Similar to the corresponding patient, heterozygous Cx40A96S mice revealed normal expression levels and localization of the Cx40 protein. We conclude that heterozygous Cx40A96S mice exhibit prolonged episodes of induced atrial fibrillation and severely reduced atrial conduction velocities similar to the corresponding human patient.
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Affiliation(s)
- Indra Lübkemeier
- Life and Medical Sciences (LIMES) Institute, Molecular Genetics, University of Bonn, Bonn, Germany
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Context dependent reversion of tumor phenotype by connexin-43 expression in MDA-MB231 cells and MCF-7 cells: role of β-catenin/connexin43 association. Exp Cell Res 2013; 319:3065-80. [PMID: 24120736 DOI: 10.1016/j.yexcr.2013.10.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2012] [Revised: 09/10/2013] [Accepted: 10/01/2013] [Indexed: 11/23/2022]
Abstract
Connexins (Cx), gap junction (GJ) proteins, are regarded as tumor suppressors, and Cx43 expression is often down regulated in breast tumors. We assessed the effect of Cx43 over-expression in 2D and 3D cultures of two breast adenocarcinoma cell lines: MCF-7 and MDA-MB-231. While Cx43 over-expression decreased proliferation of 2D and 3D cultures of MCF-7 by 56% and 80% respectively, MDA-MB-231 growth was not altered in 2D cultures, but exhibited 35% reduction in 3D cultures. C-terminus truncated Cx43 did not alter proliferation. Untransfected MCF-7 cells formed spherical aggregates in 3D cultures, and MDA-MB-231 cells formed stellar aggregates. However, MCF-7 cells over-expressing Cx43 formed smaller sized clusters and Cx43 expressing MDA-MB-231 cells lost their stellar morphology. Extravasation ability of both MCF-7 and MDA-MB-231 cells was reduced by 60% and 30% respectively. On the other hand, silencing Cx43 in MCF10A cells, nonneoplastic human mammary cell line, increased proliferation in both 2D and 3D cultures, and disrupted acinar morphology. Although Cx43 over-expression did not affect total levels of β-catenin, α-catenin and ZO-2, it decreased nuclear levels of β-catenin in 2D and 3D cultures of MCF-7 cells, and in 3D cultures of MDA-MB-231 cells. Cx43 associated at the membrane with α-catenin, β-catenin and ZO-2 in 2D and 3D cultures of MCF-7 cells, and only in 3D conditions in MDA-MB-231 cells. This study suggests that Cx43 exerts tumor suppressive effects in a context-dependent manner where GJ assembly with α-catenin, β-catenin and ZO-2 may be implicated in reducing growth rate, invasiveness, and, malignant phenotype of 2D and 3D cultures of MCF-7 cells, and 3D cultures of MDA-MB-231 cells, by sequestering β-catenin away from nucleus.
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Traditional acupuncture triggers a local increase in adenosine in human subjects. THE JOURNAL OF PAIN 2013. [PMID: 23182227 DOI: 10.1016/j.jpain.2012.09.012] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
UNLABELLED Acupuncture is a form of Eastern medicine that has been practiced for centuries. Despite its long history and worldwide application, the biological mechanisms of acupuncture in relieving pain have been poorly defined. Recent studies in mice, however, demonstrate that acupuncture triggers increases in interstitial adenosine, which reduces the severity of chronic pain through adenosine A1 receptors, suggesting that adenosine-mediated antinociception contributes to the clinical benefits of acupuncture. We asked here whether acupuncture in human subjects is also linked to a local increase in interstitial adenosine concentration. We collected microdialysis samples of interstitial fluid before, during, and after delivering 30 minutes of conventional acupuncture in the Zusanli point in human subjects. The interstitial adenosine concentration increased significantly during acupuncture and remained elevated for 30 minutes after the acupuncture. Acupuncture-mediated adenosine release was not observed if acupuncture was not delivered in the Zusanli point or if the acupuncture needle was inserted, but not rotated. This study strengthens the role of adenosine in acupuncture-mediated antinociception by directly providing such evidence in humans. PERSPECTIVE This article presents further evidence of the role of adenosine in acupuncture-mediated antinociception by demonstrating that local adenosine concentrations increase in the acupoint in human subjects receiving traditional acupuncture.
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ZHU JINGJING, VAN DE VEN WIM, VERMORKEN ALPHONS. Polyphenols with indirect proprotein convertase inhibitory activity. Int J Oncol 2013; 43:947-55. [DOI: 10.3892/ijo.2013.2009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 05/30/2013] [Indexed: 11/06/2022] Open
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May D, Tress O, Seifert G, Willecke K. Connexin47 protein phosphorylation and stability in oligodendrocytes depend on expression of Connexin43 protein in astrocytes. J Neurosci 2013; 33:7985-96. [PMID: 23637189 PMCID: PMC6618970 DOI: 10.1523/jneurosci.5874-12.2013] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2012] [Revised: 03/11/2013] [Accepted: 03/31/2013] [Indexed: 01/07/2023] Open
Abstract
Panglial networks are essential for normal physiology in the CNS, and the function of distinct connexins participating in these networks is not well understood. We generated Connexin32 (Cx32)-deficient mice with additional deletion of astrocytic Cx43 to explore the role of both connexins in panglial networks. Cx43/Cx32 double knock-out (dKO) mice revealed strong microglial activation in corpus callosum and cingulum along with severe astrogliosis and scar formation. In addition, most of the fine myelinated fibers projecting from the corpus callosum into the cortex were lost. Myelin loss was caused by a strong decrease of oligodendrocytes in the cingulum of Cx43/Cx32dKO mice. Immunoblot analyses using newly generated specific Cx47 antibodies revealed that oligodendrocytic Cx47 is phosphorylated in vivo depending on astrocytic Cx43 expression. In Cx43-deficient mice, Cx47 protein levels were strongly decreased, whereas Cx47 mRNA levels were not altered. Using Cx43G138R/Cx30KO mice, we show that Cx47 expression depends on the presence of astrocytic Cx43 protein and that its gap junctional channel function is not necessary for Cx47 stabilization. In consequence, Cx43/Cx32dKO mice additionally lack Cx47 expression and therefore cannot form oligodendrocytic gap junctions, which explains the phenotypic similarities to Cx32/Cx47dKO mice. Our findings provide strong evidence that phosphorylation and stability of oligodendrocytic Cx47 proteins is dependent on astrocytic Cx43 expression. These results further unravel the complexity of panglial networks and show that results of previous studies using astrocytic Cx43-deficient mice have to be reconsidered.
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Affiliation(s)
- Dennis May
- Life and Medical Sciences Institute, Molecular Genetics, University of Bonn, D-53115 Bonn, Germany, and
| | - Oliver Tress
- Life and Medical Sciences Institute, Molecular Genetics, University of Bonn, D-53115 Bonn, Germany, and
| | - Gerald Seifert
- Institute of Cellular Neurosciences, Medical Faculty, University of Bonn, D-53105 Bonn, Germany
| | - Klaus Willecke
- Life and Medical Sciences Institute, Molecular Genetics, University of Bonn, D-53115 Bonn, Germany, and
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Park JM, Munoz JL, Won BW, Bliss SA, Greco SJ, Patel SA, Kandouz M, Rameshwar P. Exogenous CXCL12 activates protein kinase C to phosphorylate connexin 43 for gap junctional intercellular communication among confluent breast cancer cells. Cancer Lett 2013; 331:84-91. [DOI: 10.1016/j.canlet.2012.12.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Revised: 12/05/2012] [Accepted: 12/06/2012] [Indexed: 02/03/2023]
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45
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Hieda K, Hayashi S, Kim JH, Murakami G, Cho BH, Matsubara A. Spatial relationship between expression of cytokeratin-19 and that of connexin-43 in human fetal kidney. Anat Cell Biol 2013; 46:32-8. [PMID: 23560234 PMCID: PMC3615610 DOI: 10.5115/acb.2013.46.1.32] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 02/04/2013] [Accepted: 02/04/2013] [Indexed: 11/27/2022] Open
Abstract
Connexin-43, a major gap junction protein, and cytokeratin-19, one of the intermediate filament keratins, are known to be markers of well-differentiated epithelium. In this study, we investigated the expression of these markers in the head region, lungs, and abdominal organs of 10 human mid-term fetuses. The expression of connexin-43 was found to be restricted to the dura mater, kidney, and adrenal cortex. In the kidney, we found a clear site-dependent difference in the expression pattern of these markers: connexin-43 expression was observed in the tubules of the renal cortex whereas cytokeratin-19 was strongly expressed in the collecting ducts and renal pelvis. This difference remained unchanged throughout the fetal stages examined. Immunoreactivity was not observed for either of the markers in the intrarenal vessels, including the glomeruli, and mesangial cells. Connexin-43 expression seemed to be restricted to the metanephric vesicle-derived structures that differentiate in the urogenital ridge of the splanchnic mesoderm. The adrenal cortex also originates from the same para-aortic mesoderm. In contrast, in the urogenital organs, cytokeratin-19 seemed to be expressed in ducts derived from the urogenital sinus.
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Affiliation(s)
- Keisuke Hieda
- Department of Urology, Hiroshima University School of Medicine, Hiroshima, Japan
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Abrams CK, Islam M, Mahmoud R, Kwon T, Bargiello TA, Freidin MM. Functional requirement for a highly conserved charged residue at position 75 in the gap junction protein connexin 32. J Biol Chem 2013; 288:3609-19. [PMID: 23209285 PMCID: PMC3561579 DOI: 10.1074/jbc.m112.392670] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Revised: 11/28/2012] [Indexed: 01/10/2023] Open
Abstract
Charcot Marie Tooth disease (CMT) is a group of inherited disorders characterized clinically by exclusively or predominantly peripheral nerve dysfunction. CMT1X, the most common form of X-linked CMT is caused by mutations in connexin 32 (Cx32). In this work, we used dual whole cell patch clamp recording to examine the functional effects of mutations at the Arg(75) position. This residue is highly conserved among members of the connexin family, and disease-causing mutations have been identified at this (or the corresponding) position in Cx26, Cx43, and Cx46. Thus, a better understanding of the effects of mutations of this position in Cx32 may have relevance to pathogenesis of a number of different human diseases. All three mutants associated with CMT1X (R75P, R75Q, and R75W) showed very low levels of coupling similar to those of the cells transfected with vector alone. Heterotypic pairing with Cx32 WT showed that the absence of coupling for these mutants in the homotypic configuration could be explained by shifts in their hemichannel G(j)-V(j) relations. Examination of the expression levels and gating characteristics of seven additional mutants (R75A, R75D, R75E, R75H, R75K, R75L, and R75V) at this position suggest that the positive charge at position 75 in Cx32 is required for normal channel function but not for gap junction assembly. Our studies also suggest that disease treatment strategies for CMT1X, which correct trafficking abnormalities in Cx32, may be ineffective for the group of mutations also conferring changes in gating properties of Cx32 channels.
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Affiliation(s)
- Charles K Abrams
- Department of Neurology, State University of New York, Downstate Medical Center, Brooklyn, New York 11203, USA.
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Shishido SN, Nguyen TA. Gap junction enhancer increases efficacy of cisplatin to attenuate mammary tumor growth. PLoS One 2012; 7:e44963. [PMID: 23028705 PMCID: PMC3441663 DOI: 10.1371/journal.pone.0044963] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Accepted: 08/10/2012] [Indexed: 02/05/2023] Open
Abstract
Cisplatin treatment has an overall 19% response rate in animal models with malignant tumors. Increasing gap junction activity in tumor cells provides the targets to enhance antineoplastic therapies. Previously, a new class of substituted quinolines (PQs) acts as gap junction enhancer, ability to increase the gap junctional intercellular communication, in breast cancer cells. We examined the effect of combinational treatment of PQs and antineoplastic drugs in an animal model, showing an increase in efficacy of antineoplastic drugs via the enhancement of gap junctions. Mice were implanted with estradiol-17ß (1.7 mg/pellet) before the injection of 1×107 T47D breast cancer cells subcutaneously into the inguinal region of mammary fat pad. Animals were treated intraperitoneally with DMSO (control), cisplatin (3.5 mg/kg), PQ (25 mg/kg), or a combining treatment of cisplatin and PQ. Cisplatin alone decreased mammary tumor growth by 85% while combinational treatment of cisplatin and PQ1 or PQ7 showed an additional reduction of 77% and 22% of tumor growth after 7 treatments at every 2 days, respectively. Histological results showed a significant increase of gap junction proteins, Cx43 and Cx26, in PQ-treated tissues compared to control or cisplatin. Furthermore, evidence of highly stained caspase 3 in tumors of combinational treatment (PQ and cisplatin) was seen compared to cisplatin alone. We have showed for the first time an increase in the efficacy of antineoplastic drugs through a combinational treatment with PQs, a specific class of gap junction enhancers.
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Affiliation(s)
- Stephanie N. Shishido
- Departments of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, Kansas, United States of America
| | - Thu A. Nguyen
- Departments of Diagnostic Medicine/Pathobiology, Kansas State University, Manhattan, Kansas, United States of America
- * E-mail:
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Effect of AATI, a Bowman-Birk type inhibitor from Apios americana, on proliferation of cancer cell lines. Food Chem 2011. [DOI: 10.1016/j.foodchem.2011.03.117] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Abstract
Glioblastoma is a very aggressive astrocytic tumor and most patients have 1-year survival time after diagnosis. A promising therapeutic strategy is the local delivery of the herpes simplex virus thymidine kinase gene in the tumor bed followed by ganciclovir treatment. The presence of functional gap junctions is highly relevant for the success of suicide gene therapy. Connexins are expressed in practically all tissues and form gap junctions that allow intercellular communication. Connexin 43 (Cx43) is the major connexin member being expressed in astrocytes but its status in glioblastoma is not well defined. We have investigated by immunofluorescence the presence of Cx43 in 74 human glioblastoma samples; its expression was detected in 77% of the samples analyzed. We report here that glioblastoma is a heterogenous disease as regards Cx43 expression with presentations, in which Cx43 expression is unaltered, reduced or totally lost. A predominant Cx43 cytoplasmic localization was observed in four out of eight primary glioblastoma cultures that we have established. This aberrant localization reduced gap junctionnal intercellular communication by 50 to 75% as compared with primary cell cultures displaying gap junctional plaques. However, the bystander effect evaluated after lentiviral delivery of the herpes simplex virus thymidine kinase gene and ganciclovir treatment was detected in all Cx43-positive primary cell cultures, and it was independant of the Cx43 localization. These findings may have important clinical implications for the design of anticancer cytotoxic therapies that rely on the gap junction-mediated bystander effect for their success.
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Expression of gap junction protein connexin 43 in bovine urinary bladder tumours. J Comp Pathol 2011; 144:86-90. [PMID: 20643416 DOI: 10.1016/j.jcpa.2010.05.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2009] [Revised: 04/09/2010] [Accepted: 05/26/2010] [Indexed: 11/24/2022]
Abstract
The aetiopathogenesis of urinary bladder tumours in cattle involves prolonged ingestion of bracken fern and infection by bovine papillomavirus types 1 or 2 (BPV-1/2). The oncogenic activity of BPV is largely associated with the major oncoprotein E5. Gap junctions are the only communicating junctions found in animal tissues and are composed of proteins known as connexins. Alterations in connexin expression have been associated with oncogenesis. The present study investigated biochemically and immunohistochemically the expression of connexin 43 in samples of normal (n=2), dysplastic (n=3) and neoplastic (n=23) bovine urothelium. The tumours included 10 carcinomas in situ, five papillary urothelial carcinomas and eight invasive urothelial carcinomas. Normal and dysplastic urothelium had membrane expression of connexin 43, but this was reduced in samples of carcinoma in situ. Papillary urothelial carcinomas showed moderate cytoplasmic and membrane labelling, while invasive carcinoma showed loss of connexin 43 expression.
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