|
1
|
Pourjamal N, Shirkoohi R, Rohani E, Hashemi M. The Expression Analysis of MEST1 and GJA1 Genes in Gastric Cancer in Association with Clinicopathological Characteristics. Int J Hematol Oncol Stem Cell Res 2024; 18:83-91. [PMID: 38680714 PMCID: PMC11055422 DOI: 10.18502/ijhoscr.v18i1.14747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 11/06/2023] [Indexed: 05/01/2024] Open
Abstract
Background: Gastric cancer is an invasive cancer, which is usually diagnosed in advanced stages. However, the markers affecting its progression, and invasion are of great importance in its diagnosis and treatment. The current research aimed to study the correlation of genes that contributed to epithelial-mesenchymal transition (EMT), Mest1, and GjA1, with some clinicopathological specifications in gastric cancer patients to better comprehend the functions of these genes in this tumor. Materials and Methods: RNA was extracted from the tumor, and normal tissues and cDNA were synthesized. Then, by designing specific primers for Gja1 and Mest1 genes, their expressions were studied by RT-PCR. The data was analyzed by GraphPad Prism 8 software. Results: Significant differences among the expressions of mentioned genes associated with clinicopathological variables of gastric cancer patients, including tumor size, grade, stage, metastasis, and lymphatic invasion were seen. Conclusion: The obtained data showed the important role of EMT-related genes, Gja1 and Mest1 in the clinical progression of the tumor. Further studies with larger sample sizes are required to confirm these genes as biomarker candidates for detecting gastric cancer.
Collapse
Affiliation(s)
- Nooshin Pourjamal
- Department of Genetics, Islamic Azad University, Tehran Medical Sciences Branch, Tehran, Iran
| | - Reza Shirkoohi
- Cancer Biology Research Center, Cancer Research Institute, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran
| | - Elham Rohani
- Department of Genetics, Islamic Azad University, Tehran Medical Sciences Branch, Tehran, Iran
| | - Mehrdad Hashemi
- Farhikhtegan Medical Convergence Sciences Research Center, Farhikhtegan Hospital Tehran Medical Sciences, Islamic Azad University, Tehran, Iran
| |
Collapse
|
|
2
|
Seeger AY, Zaidi F, Alhayek S, Jones RM, Zohair H, Holland RL, Kim IJ, Blanke SR. Host cell sensing and restoration of mitochondrial function and metabolism within Helicobacter pylori VacA intoxicated cells. mBio 2023; 14:e0211723. [PMID: 37815365 PMCID: PMC10653863 DOI: 10.1128/mbio.02117-23] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Accepted: 08/23/2023] [Indexed: 10/11/2023] Open
Abstract
IMPORTANCE Persistent human gastric infection with Helicobacter pylori is the single most important risk factor for development of gastric malignancy, which is one of the leading causes of cancer-related deaths worldwide. An important virulence factor for Hp colonization and severity of gastric disease is the protein exotoxin VacA, which is secreted by the bacterium and modulates functional properties of gastric cells. VacA acts by damaging mitochondria, which impairs host cell metabolism through impairment of energy production. Here, we demonstrate that intoxicated cells have the capacity to detect VacA-mediated damage, and orchestrate the repair of mitochondrial function, thereby restoring cellular health and vitality. This study provides new insights into cellular recognition and responses to intracellular-acting toxin modulation of host cell function, which could be relevant for the growing list of pathogenic microbes and viruses identified that target mitochondria as part of their virulence strategies.
Collapse
Affiliation(s)
- Ami Y. Seeger
- Department of Microbiology, University of Illinois, Urbana, Illinois, USA
| | - Faisal Zaidi
- Department of Microbiology, University of Illinois, Urbana, Illinois, USA
| | - Sammy Alhayek
- Department of Microbiology, University of Illinois, Urbana, Illinois, USA
| | - Rachel M. Jones
- Department of Microbiology, University of Illinois, Urbana, Illinois, USA
| | - Huzaifa Zohair
- Department of Microbiology, University of Illinois, Urbana, Illinois, USA
| | - Robin L. Holland
- Department of Pathobiology, University of Illinois, Urbana, Illinois, USA
| | - Ik-Jung Kim
- Department of Microbiology, University of Illinois, Urbana, Illinois, USA
- Buck Institute for Research on Aging, Novato, California, USA
| | - Steven R. Blanke
- Department of Microbiology, University of Illinois, Urbana, Illinois, USA
- Department of Pathobiology, University of Illinois, Urbana, Illinois, USA
- Department of Biomedical and Translational Medicine, University of Illinois, Urbana, Illinois, USA
| |
Collapse
|
|
3
|
Bahuguna A, Dubey SK. Relevance of tumor microbiome in cancer incidence, prognosis, and its clinical implications in therapeutics. Biochim Biophys Acta Rev Cancer 2023; 1878:188956. [PMID: 37473857 DOI: 10.1016/j.bbcan.2023.188956] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 07/07/2023] [Accepted: 07/13/2023] [Indexed: 07/22/2023]
Abstract
The microbiota is garnering progressively greater consideration as an essential facet of the tumor microenvironment that regulates tumor proliferation and affects cancer prognosis. Microbial populations that inhabit different body locations are involved in the carcinogenesis and tumor progression of their corresponding malignancies. It has been learned that the microbial populations primarily thriving within tumors are tumor-type specific. Mechanistic studies have revealed that the tumor-associated microbiota contributes to playing a pivotal role in the establishment of the tumor microenvironment, regulation of local immunity, modulation of tumor cell biology, and directly influences the therapeutic efficacy of drug treatment for tumors. This review article incorporates the pertinent studies on recent advancements in tumor microbiome studies, the interplay between the intratumor microbiota and cancer, and, discusses their role and mechanism of action in the emergence and treatment of cancer, and their relationship to clinical characteristics.
Collapse
Affiliation(s)
- Ananya Bahuguna
- Department of Biochemistry, College of Basic Sciences and Humanities, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar 263145, Uttarakhand, India
| | - Shiv Kumar Dubey
- Department of Biochemistry, College of Basic Sciences and Humanities, Govind Ballabh Pant University of Agriculture and Technology, Pantnagar 263145, Uttarakhand, India.
| |
Collapse
|
|
4
|
Sadrekarimi H, Gardanova ZR, Bakhshesh M, Ebrahimzadeh F, Yaseri AF, Thangavelu L, Hasanpoor Z, Zadeh FA, Kahrizi MS. Emerging role of human microbiome in cancer development and response to therapy: special focus on intestinal microflora. Lab Invest 2022; 20:301. [PMID: 35794566 PMCID: PMC9258144 DOI: 10.1186/s12967-022-03492-7] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Accepted: 06/20/2022] [Indexed: 12/12/2022]
Abstract
In recent years, there has been a greater emphasis on the impact of microbial populations inhabiting the gastrointestinal tract on human health and disease. According to the involvement of microbiota in modulating physiological processes (such as immune system development, vitamins synthesis, pathogen displacement, and nutrient uptake), any alteration in its composition and diversity (i.e., dysbiosis) has been linked to a variety of pathologies, including cancer. In this bidirectional relationship, colonization with various bacterial species is correlated with a reduced or elevated risk of certain cancers. Notably, the gut microflora could potentially play a direct or indirect role in tumor initiation and progression by inducing chronic inflammation and producing toxins and metabolites. Therefore, identifying the bacterial species involved and their mechanism of action could be beneficial in preventing the onset of tumors or controlling their advancement. Likewise, the microbial community affects anti-cancer approaches’ therapeutic potential and adverse effects (such as immunotherapy and chemotherapy). Hence, their efficiency should be evaluated in the context of the microbiome, underlining the importance of personalized medicine. In this review, we summarized the evidence revealing the microbiota's involvement in cancer and its mechanism. We also delineated how microbiota could predict colon carcinoma development or response to current treatments to improve clinical outcomes.
Collapse
|
|
5
|
Ansari S, Yamaoka Y. Role of vacuolating cytotoxin A in Helicobacter pylori infection and its impact on gastric pathogenesis. Expert Rev Anti Infect Ther 2020; 18:987-996. [PMID: 32536287 DOI: 10.1080/14787210.2020.1782739] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Introduction Helicobacter pylori causes, via the influence of several virulence factors, persistent infection of the stomach, which leads to severe complications. Vacuolating cytotoxin A (VacA) is observed in almost all clinical strains of H. pylori; however, only some strains produce the toxigenic and pathogenic VacA, which is influenced by the gene sequence variations. VacA exerts its action by causing cell vacuolation and apoptosis. We performed a PubMed search to review the latest literatures published in English language. Areas covered Articles regarding H. pylori VacA and its genotypes, architecture, internalization, and role in gastric infection and pathogenicity are reviewed. We included the search for recently published literature until January 2020. Expert opinion H. pylori VacA plays a crucial role in severe gastric pathogenicity. In addition, VacA mediated in vivo bacterial survival leads to persistent infection and an enhanced bacterial evasion from the action of antibiotics and the innate host defense system, which leads to drug evasion. VacA as a co-stimulator for the CagA phosphorylation may exert a synergistic effect playing an important role in the CagA-mediated pathogenicity.
Collapse
Affiliation(s)
- Shamshul Ansari
- Department of Microbiology, Chitwan Medical College , Bharatpur, Nepal
| | - Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine , Yufu, Oita, Japan.,Global Oita Medical Advanced Research Center for Health , Yufu, Oita, Japan.,Department of Medicine, Gastroenterology and Hepatology Section, Baylor College of Medicine , Houston, TX, USA.,Borneo Medical and Health Research Centre, Universiti Malaysia Sabah , Kota Kinabaru, Malaysia
| |
Collapse
|
|
6
|
Sukri A, Hanafiah A, Mohamad Zin N, Kosai NR. Epidemiology and role of Helicobacter pylori virulence factors in gastric cancer carcinogenesis. APMIS 2020; 128:150-161. [PMID: 32352605 DOI: 10.1111/apm.13034] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 02/09/2020] [Indexed: 02/06/2023]
Abstract
Infection with Helicobacter pylori is associated with the development of gastric cancer. Although the prevalence of gastric cancer has declined throughout years due to improvement in early screening strategy, mortality due to gastric cancer has not changed. Incidence and mortality due to gastric cancer are higher in developing countries as compared to developed countries. Diagnosis and prognosis of gastric cancer are still poor with patients usually diagnosed with cancer at an advanced stage. Eradication of H. pylori is pertinent for the prevention of gastric cancer. However, the rise in antimicrobial resistance among H. pylori isolates has complicated the prevention strategy. H. pylori express multiple virulence factors for survival in the hostile acid gastric environment. The expression of oncogenic protein cytotoxin-associated gene A (CagA), vacuolating cytotoxin A (VacA), and outer inflammatory protein is essential for H. pylori to exert pathogenesis towards the host. Interestingly, <3% of H. pylori-infected subjects develop gastric cancer, suggesting a unique way of interaction between the host's immune response and H. pylori virulence factors. This article is aimed to review the epidemiology and role of H. pylori in gastric carcinogenesis. A better understanding of the interaction between H. pylori virulence factors and host is required for better gastric cancer prevention.
Collapse
Affiliation(s)
- Asif Sukri
- Programme of Biomedical Science, Faculty of Health Science, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - Alfizah Hanafiah
- Department of Medical Microbiology and Immunology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - Noraziah Mohamad Zin
- Programme of Biomedical Science, Faculty of Health Science, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| | - Nik Ritza Kosai
- Department of Surgery, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
| |
Collapse
|
|
7
|
Li H, Xu CX, Gong RJ, Chi JS, Liu P, Liu XM. How does Helicobacter pylori cause gastric cancer through connexins: An opinion review. World J Gastroenterol 2019; 25:5220-5232. [PMID: 31558869 PMCID: PMC6761244 DOI: 10.3748/wjg.v25.i35.5220] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 08/12/2019] [Accepted: 08/19/2019] [Indexed: 02/06/2023] Open
Abstract
Helicobacter pylori (H. pylori) is a Gram-negative bacterium with a number of virulence factors, such as cytotoxin-associated gene A, vacuolating cytotoxin A, its pathogenicity island, and lipopolysaccharide, which cause gastrointestinal diseases. Connexins function in gap junctional homeostasis, and their downregulation is closely related to gastric carcinogenesis. Investigations into H. pylori infection and the fine-tuning of connexins in cells or tissues have been reported in previous studies. Therefore, in this review, the potential mechanisms of H. pylori-induced gastric cancer through connexins are summarized in detail.
Collapse
Affiliation(s)
- Huan Li
- Department of Gastroenterology, the Third Xiangya Hospital of Central South University, Changsha 410013, Hunan Province, China
| | - Can-Xia Xu
- Department of Gastroenterology, the Third Xiangya Hospital of Central South University, Changsha 410013, Hunan Province, China
| | - Ren-Jie Gong
- Department of Gastroenterology, the Third Xiangya Hospital of Central South University, Changsha 410013, Hunan Province, China
| | - Jing-Shu Chi
- Department of Gastroenterology, the Third Xiangya Hospital of Central South University, Changsha 410013, Hunan Province, China
| | - Peng Liu
- Department of Gastroenterology, the Third Xiangya Hospital of Central South University, Changsha 410013, Hunan Province, China
| | - Xiao-Ming Liu
- Department of Gastroenterology, the Third Xiangya Hospital of Central South University, Changsha 410013, Hunan Province, China
| |
Collapse
|
|
8
|
Li H, Xu CX, Gong RJ, Chi JS, Liu P, Liu XM. How does Helicobacter pyloricause gastric cancer through connexins: An opinion review. World J Gastroenterol 2019. [DOI: 10.3748/wjg.v25.i355220] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
|
|
9
|
Eslami M, Yousefi B, Kokhaei P, Arabkari V, Ghasemian A. Current information on the association of Helicobacter pylori with autophagy and gastric cancer. J Cell Physiol 2019; 234:14800-14811. [PMID: 30784066 DOI: 10.1002/jcp.28279] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 11/23/2018] [Accepted: 11/30/2018] [Indexed: 01/24/2023]
Abstract
Helicobacter pylori (H. pylori) is a Gram-negative bacterium and causative agent of gastric cancer. H. pylori induce defective autophagy or inhibit it by means of CagA and vacuolating cytotoxin A (VacA) toxins leading to the gastric cancer induction. Impaired or defective autophagy leads to the accumulation of cytotoxic materials, such as ROS and P62 that lead to increased mutations in the DNA, genome instability, and risk of cancer formation. H. pylori CagA may inhibit autophagy through the c-Met-PI3k/Akt-mTOR signaling pathway. However, VacA induces autophagy by some signaling pathways. In the gastric epithelial cells, VacA is a necessary and sufficient factor for the creation of autophagy. While CagA is a negative regulator of this phenomenon, the elimination of this gene from H. pylori has increased autophagy and the production of inflammatory cytokines is reduced. In gastrointestinal cancers, some of the microRNAs (miRNAs) act as tumor suppressors and some other are oncogenes by regulating various genes expression. H. pylori can also modify autophagy through a mechanism that includes the function of miRNAs. In autophagy, oncogenic miRNAs inhibit activation of some tumor suppressor signaling pathways (e.g., ULK1 complex, Beclin-1 function, and Atg4 messaging), whereas tumor suppressor miRNAs can block the activation of oncogenic signaling pathways. For instance, Beclin-1 is negatively regulated by miRNA-376b (oncogenic miRNA) and miRNA-30a (tumor suppressor miRNA). Similarly, Atg4 by miRNA-376b (oncogenic miRNA) and miRNA-101 (tumor suppressor miRNA). So, this apparent paradox can be explained as that both Beclin-1 and Atg4 play different roles in a particular cell or tissue.
Collapse
Affiliation(s)
- Majid Eslami
- Department of Bacteriology and Virology, Semnan University of Medical Sciences, Semnan, Iran
| | - Bahman Yousefi
- Department of Immunology, Semnan University of Medical Sciences, Semnan, Iran
| | - Parviz Kokhaei
- Cancer Research Center, Semnan University of Medical Sciences, Semnan, Iran
- Immune and Gene Therapy Lab, Cancer Centre Karolinska, Karolinska University Hospital, Stockholm, Sweden
| | - Vahid Arabkari
- Discipline of Pathology, Lambe Institute for Translational Research, Clinical Science Institute, School of Medicine, National University of Ireland, Galway, Ireland
| | | |
Collapse
|
|
10
|
Gupta N, Maurya S, Verma H, Verma VK. Unraveling the factors and mechanism involved in persistence: Host-pathogen interactions in Helicobacter pylori. J Cell Biochem 2019; 120:18572-18587. [PMID: 31237031 DOI: 10.1002/jcb.29201] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Accepted: 05/20/2019] [Indexed: 12/15/2022]
Abstract
Helicobacter pylori and humans have one of the most complex relationships in nature. How a bacterium manages to live in one of the harshest and hostile environments is a topic of unraveling mysteries. H. pylori is a prevalent species and it colonizes the human gut of more than 50% of the world population. It infects the epithelial region of antrum and persists there for a long period. Over the time of evolution, H. pylori has developed complex strategies to extend the degree of inflammation in gastric mucosa. H. pylori needs specific adaptations for initial colonization into the host environment like helical shape, flagellar movement, chemotaxis, and the production of urease enzyme that neutralizes acidic environment of the stomach. There are several factors from the bacterium as well as from the host that participate in these complex interactions. On the other hand, to establish the persistent infection, H. pylori escapes the immune system by mimicking the host antigens. This pathogen has the ability to dodge the immune system and then persist there in the form of host cell, which leads to immune tolerance. H. pylori has an ability to manipulate its own pathogen-associated molecular patterns, which leads to an inhibition in the binding with specific pattern recognition receptors of the host to avoid immune cell detection. Also, it manipulates the host metabolic homeostasis in the gastric epithelium. Besides, it has several genes, which may get involved in the acquisition of nutrition from the host to survive longer in the host. Due to the persistence of H. pylori, it causes chronic inflammation and raises the chances of gastric cancer. This review highlights the important elements, which are certainly responsible for the persistence of H. pylori in the human host.
Collapse
Affiliation(s)
- Nidhi Gupta
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Kishangarh, India
| | - Shweta Maurya
- Department of Microbiology, School of Life Sciences, Central University of Rajasthan, Kishangarh, India
| | - Harshvardhan Verma
- Department of Microbiology, School of Life Sciences, Central University of Rajasthan, Kishangarh, India
| | - Vijay K Verma
- Department of Microbiology, School of Life Sciences, Central University of Rajasthan, Kishangarh, India
| |
Collapse
|
|
11
|
Zhao X, Yu C, Zheng M, Sun J. Prognostic value of the mRNA expression of gap junction α members in patients with gastric cancer. Oncol Lett 2019; 18:1669-1678. [PMID: 31423234 PMCID: PMC6614678 DOI: 10.3892/ol.2019.10516] [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: 07/24/2018] [Accepted: 05/02/2019] [Indexed: 12/15/2022] Open
Abstract
Gastric cancer remains one of the primary causes of cancer-associated death worldwide. The gap junction α (GJA) family has been demonstrated to be involved in the cellular proliferation and metastasis of gastric cancer. However, the prognostic value of GJA in gastric cancer is yet to be elucidated. In the present study, the overall survival (OS) of patients with gastric cancer and the mRNA expression of GJA family members, including GJA1, GJA3, GJA4, GJA10 and GJA12, were analyzed using 593 patients with gastric cancer from the Kaplan-Meier plotter database. High GJA1 and GJA10 mRNA expression levels were associated with a poorer patient outcome (P=0.0066 and P=0.015, respectively), whereas high mRNA expression levels of GJA4 and GJA12 were associated with longer survival times (P=0.0056 and P=0.0054, respectively). Furthermore, the values of specific prognostic indicators of different subtypes of gastric cancer, including human epidermal growth factor receptor 2 status, Lauren differentiation and tumor stage, were also analyzed. The findings of the present study suggested a potential role for GJA family members in gastric cancer, which warrants further investigation.
Collapse
Affiliation(s)
- Xuan Zhao
- Department of General Surgery, Shanghai Minimally Invasive Surgery Center, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, P.R. China
| | - Chaoran Yu
- Department of General Surgery, Shanghai Minimally Invasive Surgery Center, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, P.R. China
| | - Minhua Zheng
- Department of General Surgery, Shanghai Minimally Invasive Surgery Center, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, P.R. China
| | - Jing Sun
- Department of General Surgery, Shanghai Minimally Invasive Surgery Center, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, P.R. China
| |
Collapse
|
|
12
|
Shi B, Xue M, Wang Y, Wang Y, Li D, Zhao X, Li X. An improved method for increasing the efficiency of gene transfection and transduction. INTERNATIONAL JOURNAL OF PHYSIOLOGY, PATHOPHYSIOLOGY AND PHARMACOLOGY 2018; 10:95-104. [PMID: 29755642 PMCID: PMC5943608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 04/11/2018] [Indexed: 06/08/2023]
Abstract
Transfection and transduction using lentivirus has gained attention in biomedical research. To date, how to reach the maximum transfection and viral transduction efficiency is still challenging. Here we compared the transfection and viral transduction efficiency using commercially available transfection reagents including FuGENE 6, Lipofectamine 2000 and Lipofectamine 3000 in different cell lines and primary cultured cells. Enhanced green fluorescent protein (EGFP) was clearly seen in Eppendorf tubes from harvested cells using Lipofectamine 3000 without using a microscope and UV activation. Strong expression of EGFP was observed in HEK293 cells, mouse primary cortical neurons and human umbilical vein endothelial cells (HUVECs) using confocal microscopy. Western blot showed the strongest EGFP expression using cell lysates from Lipofectamine 3000 transfected HEK293 cells and transduced HUVECs compared with Lipofectamine 2000 or FuGENE 6 reagents. Using Cx43 shRNA lentivirus combined with Lipofectamine 3000 transfection reagent, we can achieve about 90% Cx43 knockdown efficacy in HUVECs. Therefore, our results suggest that a much higher transfection and viral transduction efficiency can be attained by using Lipofectamine 3000 transfection reagent.
Collapse
Affiliation(s)
- Baomin Shi
- Department of General Surgery, Tongji Hospital, Tongji UniversityShanghai, China
| | - Mengzhou Xue
- Department of Neurorehabilitation, The Second Affiliated Hospital of Zhengzhou UniversityZhengzhou, China
| | - Yi Wang
- Department of Ophthalmology, Taishan Medical UniversityTaian, China
| | - Yufeng Wang
- Department of General Surgery, Tongji Hospital, Tongji UniversityShanghai, China
| | - Davey Li
- University of WaterlooWaterloo, Canada
| | - Xiaomin Zhao
- Institute of Pharmacology, Taishan Medical UniversityTaian, China
| | - Xinbo Li
- Casey Eye Institute, Oregon Health & Science UniversityPortland, Oregon, USA
| |
Collapse
|
|
13
|
Shubin AV, Demidyuk IV, Komissarov AA, Rafieva LM, Kostrov SV. Cytoplasmic vacuolization in cell death and survival. Oncotarget 2018; 7:55863-55889. [PMID: 27331412 PMCID: PMC5342458 DOI: 10.18632/oncotarget.10150] [Citation(s) in RCA: 238] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Accepted: 06/06/2016] [Indexed: 12/15/2022] Open
Abstract
Cytoplasmic vacuolization (also called cytoplasmic vacuolation) is a well-known morphological phenomenon observed in mammalian cells after exposure to bacterial or viral pathogens as well as to various natural and artificial low-molecular-weight compounds. Vacuolization often accompanies cell death; however, its role in cell death processes remains unclear. This can be attributed to studying vacuolization at the level of morphology for many years. At the same time, new data on the molecular mechanisms of the vacuole formation and structure have become available. In addition, numerous examples of the association between vacuolization and previously unknown cell death types have been reported. Here, we review these data to make a deeper insight into the role of cytoplasmic vacuolization in cell death and survival.
Collapse
Affiliation(s)
- Andrey V Shubin
- Laboratory of Protein Engineering, Institute of Molecular Genetics, Moscow, Russia.,Laboratory of Chemical Carcinogenesis, N.N. Blokhin Russian Cancer Research Center, Moscow, Russia.,Laboratory of Biologically Active Nanostructures, N.F. Gamaleya Institute of Epidemiology and Microbiology, Moscow, Russia
| | - Ilya V Demidyuk
- Laboratory of Protein Engineering, Institute of Molecular Genetics, Moscow, Russia
| | - Alexey A Komissarov
- Laboratory of Protein Engineering, Institute of Molecular Genetics, Moscow, Russia
| | - Lola M Rafieva
- Laboratory of Protein Engineering, Institute of Molecular Genetics, Moscow, Russia
| | - Sergey V Kostrov
- Laboratory of Protein Engineering, Institute of Molecular Genetics, Moscow, Russia
| |
Collapse
|
|
14
|
Helicobacter pylori VacA induces autophagic cell death in gastric epithelial cells via the endoplasmic reticulum stress pathway. Cell Death Dis 2017; 8:3207. [PMID: 29238039 PMCID: PMC5870595 DOI: 10.1038/s41419-017-0011-x] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 09/25/2017] [Accepted: 10/02/2017] [Indexed: 12/19/2022]
Abstract
The Helicobacter pylori vacuolating cytotoxin (VacA) can promote progressive vacuolation and gastric injury and may be associated with human gastric cancer. Increasing evidence indicates that autophagy is involved in the cell death induced by VacA, but the specific mechanisms need to be further elucidated. We show here that VacA could induce autophagy and increase cell death in human gastric cancer cell lines. Further investigations revealed that inhibition of autophagy could decrease the VacA-induced cell death in AGS cells. Furthermore, numerous dilated endoplasmic reticula (ER) were observed, and the phosphorylation of a subunit of eukaryotic translation initiation factor 2 subunit 1 also increased in the VacA-treated AGS cells, while repression of ER stress could reduce autophagy and cell death through knockdown of activating transcription factor 4 and DNA-damage-inducible transcript 3. In addition, the expression of pseudokinase tribbles homolog 3 (TRIB3) upon ER stress was triggered by VacA, and knockdown of TRIB3 could also decrease VacA-induced cell death. Finally, inhibition of autophagy could decrease VacAs1m1-induced cell death and apoptosis, and apoptosis inhibitor Z-VAD had no significant effect on autophagy induced by VacAs1m1. Thus, these results suggested that VacA causes autophagic cell death via ER stress in gastric epithelial cells.
Collapse
|
|
15
|
Nakano M, Yahiro K, Yamasaki E, Kurazono H, Akada J, Yamaoka Y, Niidome T, Hatakeyama M, Suzuki H, Yamamoto T, Moss J, Isomoto H, Hirayama T. Helicobacter pylori VacA, acting through receptor protein tyrosine phosphatase α, is crucial for CagA phosphorylation in human duodenum carcinoma cell line AZ-521. Dis Model Mech 2017; 9:1473-1481. [PMID: 27935824 PMCID: PMC5200893 DOI: 10.1242/dmm.025361] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 10/11/2016] [Indexed: 12/16/2022] Open
Abstract
Helicobacter pylori, a major cause of gastroduodenal diseases, produces vacuolating cytotoxin (VacA) and cytotoxin-associated gene A (CagA), which seem to be involved in virulence. VacA exhibits pleiotropic actions in gastroduodenal disorders via its specific receptors. Recently, we found that VacA induced the phosphorylation of cellular Src kinase (Src) at Tyr418 in AZ-521 cells. Silencing of receptor protein tyrosine phosphatase (RPTP)α, a VacA receptor, reduced VacA-induced Src phosphorylation. Src is responsible for tyrosine phosphorylation of CagA at its Glu-Pro-Ile-Tyr-Ala (EPIYA) variant C (EPIYA-C) motif in Helicobacterpylori-infected gastric epithelial cells, resulting in binding of CagA to SHP-2 phosphatase. Challenging AZ-521 cells with wild-type H. pylori induced phosphorylation of CagA, but this did not occur when challenged with a vacA gene-disrupted mutant strain. CagA phosphorylation was observed in cells infected with a vacA gene-disrupted mutant strain after addition of purified VacA, suggesting that VacA is required for H. pylori-induced CagA phosphorylation. Following siRNA-mediated RPTPα knockdown in AZ-521 cells, infection with wild-type H. pylori and treatment with VacA did not induce CagA phosphorylation. Taken together, these results support our conclusion that VacA mediates CagA phosphorylation through RPTPα in AZ-521 cells. These data indicate the possibility that Src phosphorylation induced by VacA is mediated through RPTPα, resulting in activation of Src, leading to CagA phosphorylation at Tyr972 in AZ-521 cells. Summary: The authors show a newly identified role of VacA in Helicobacter pylori infection through induction of tyrosine phosphorylation of CagA acting through the VacA receptor RPTPα.
Collapse
Affiliation(s)
- Masayuki Nakano
- Department of Bacteriology, Institute of Tropical Medicine, Nagasaki University, 1-12-4, Sakamoto, Nagasaki 852-8523, Japan .,Department of International Health, Institute of Tropical Medicine, Nagasaki University, 1-12-4, Sakamoto, Nagasaki 852-8523, Japan
| | - Kinnosuke Yahiro
- Department of Molecular Infectiology, Graduate School of Medicine, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba 260-8670, Japan
| | - Eiki Yamasaki
- Division of Food Hygiene, Department of Animal and Food Hygiene, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11, Inada-cho, Obihiro, Hokkaido 080-8555, Japan
| | - Hisao Kurazono
- Division of Food Hygiene, Department of Animal and Food Hygiene, Obihiro University of Agriculture and Veterinary Medicine, Nishi 2-11, Inada-cho, Obihiro, Hokkaido 080-8555, Japan
| | - Junko Akada
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Idaigaoka 1-1, Yufu, Oita 879-5593, Japan
| | - Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Idaigaoka 1-1, Yufu, Oita 879-5593, Japan.,Department of Medicine, Gastroenterology and Hepatology Section, Baylor College of Medicine, Houston, TX 77030, USA
| | - Takuro Niidome
- Department of Applied Chemistry and Biochemistry, Graduate School of Science and Technology, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto 860-8555, Japan
| | - Masanori Hatakeyama
- Division of Microbiology, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo 113-0033, Japan
| | - Hidekazu Suzuki
- Medical Education Center, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Taro Yamamoto
- Department of International Health, Institute of Tropical Medicine, Nagasaki University, 1-12-4, Sakamoto, Nagasaki 852-8523, Japan
| | - Joel Moss
- Cardiovascular and Pulmonary Branch, NHLBI, National Institutes of Health, Bethesda, MD 20892-1590, USA
| | - Hajime Isomoto
- Division of Medicine and Clinical Science, Tottori University Faculty of Medicine, 86 Nishi-cho, Yonago, Tottori 683-8503, Japan
| | - Toshiya Hirayama
- Department of Bacteriology, Institute of Tropical Medicine, Nagasaki University, 1-12-4, Sakamoto, Nagasaki 852-8523, Japan
| |
Collapse
|
|
16
|
McClain MS, Beckett AC, Cover TL. Helicobacter pylori Vacuolating Toxin and Gastric Cancer. Toxins (Basel) 2017; 9:toxins9100316. [PMID: 29023421 PMCID: PMC5666363 DOI: 10.3390/toxins9100316] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Revised: 10/03/2017] [Accepted: 10/05/2017] [Indexed: 12/13/2022] Open
Abstract
Helicobacter pylori VacA is a channel-forming toxin unrelated to other known bacterial toxins. Most H. pylori strains contain a vacA gene, but there is marked variation among strains in VacA toxin activity. This variation is attributable to strain-specific variations in VacA amino acid sequences, as well as variations in the levels of VacA transcription and secretion. In this review, we discuss epidemiologic studies showing an association between specific vacA allelic types and gastric cancer, as well as studies that have used animal models to investigate VacA activities relevant to gastric cancer. We also discuss the mechanisms by which VacA-induced cellular alterations may contribute to the pathogenesis of gastric cancer.
Collapse
Affiliation(s)
- Mark S McClain
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
| | - Amber C Beckett
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
| | - Timothy L Cover
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, USA.
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, TN 37212, USA.
| |
Collapse
|
|
17
|
Abadi ATB. Strategies used by helicobacter pylori to establish persistent infection. World J Gastroenterol 2017; 23:2870-2882. [PMID: 28522905 PMCID: PMC5413782 DOI: 10.3748/wjg.v23.i16.2870] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 02/01/2017] [Accepted: 02/16/2017] [Indexed: 02/06/2023] Open
Abstract
Helicobacter pylori (H. pylori) is a Gram-negative and motile bacterium that colonizes the hostile microniche of the human stomach, then persists for the host's entire life, if not effectively treated. Clinically, H. pylori plays a causative role in the development of a wide spectrum of diseases including chronic active gastritis, peptic ulceration, gastric adenocarcinoma, and gastric mucosa-associated lymphoid tissue lymphoma. Due to the global distribution of H. pylori, it is no exaggeration to conclude that smart strategies are contributing to adaptation of the bacterium to its permanent host. Thirty-four years after the discovery of this bacterium, there are still many unanswered questions. For example, which strategies help the bacterium to survive in this inhospitable microniche? This question is slightly easier to answer if we presume the same clinical concept for both persistent infection and disease. Understanding the mechanisms governing H. pylori persistence will improve identification of the increased risk of diseases such as gastric cancer in patients infected with this bacterium. A well-defined and long-term equilibrium between the human host and H. pylori allows bacterial persistence in the gastric microniche; although this coexistence leads to a high risk of severe diseases such as gastric cancer. To escape the bactericidal activity of stomach acid, H. pylori secretes large amounts of surface-associated and cytosolic urease. The potential to avoid acidic conditions and immune evasion are discussed in order to explain the persistence of H. pylori colonization in the gastric mucosa, and data on bacterial genetic diversity are included. Information on the mechanisms related to H. pylori persistence can also provide the direction for future research concerning effective therapy and management of gastroduodenal disorders. The topics presented in the current review are important for elucidating the strategies used by H. pylori to help the bacterium persist in relation to the immune system and the many unfavorable features of living in the gastric microniche.
Collapse
|
|
18
|
MIFTAHUSSURUR MUHAMMAD, YAMAOKA YOSHIO, GRAHAM DAVIDY. Helicobacter pylori as an oncogenic pathogen, revisited. Expert Rev Mol Med 2017; 19:e4. [PMID: 28322182 PMCID: PMC6905048 DOI: 10.1017/erm.2017.4] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Gastric cancer is an inflammation-associated malignancy aetiologically related to infection with the bacterium, Helicobacter pylori, which is considered a necessary but insufficient cause. Unless treated, H. pylori causes life-long acute and chronic gastric inflammation resulting in progressive gastric mucosal damage that may result in gastric cancer. The rate of progression from superficial gastritis, to an atrophic metaplastic mucosa, and ultimately to cancer relates to the virulence of the infecting H. pylori as well as host and environmental factors. H. pylori virulence is a reflection of its propensity to cause severe gastric inflammation. Both mucosal inflammation and H. pylori can cause host genomic instability, including dysregulation of DNA mismatch repair, stimulation of expression of activation-induced cytidine deaminase, abnormal DNA methylation and dysregulation of micro RNAs, which may result in an accumulation of mutations and loss of normal regulation of cell growth. The difference in cancer risk between the most and least virulent H. pylori strain is only approximately 2-fold. Overall, none of the putative virulence factors identified to date have proved to be disease-specific. The presence, severity, extent and duration of inflammation appear to be the most important factors and current evidence suggests that any host, environmental or bacterial factor that reliably enhances the inflammatory response to the H. pylori infection increases the risk of gastric cancer.
Collapse
Affiliation(s)
- MUHAMMAD MIFTAHUSSURUR
- Department of Medicine, Gastroenterology and Hepatology Section, Baylor College of Medicine, Houston, Texas 77030, USA
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu 879-5593, Japan
- Gastroentero-Hepatology Division, Department of Internal Medicine, Faculty of Medicine – Dr Soetomo Teaching Hospital – Institute of Tropical Disease, Universitas Airlangga, Surabaya 60115, Indonesia
| | - YOSHIO YAMAOKA
- Department of Medicine, Gastroenterology and Hepatology Section, Baylor College of Medicine, Houston, Texas 77030, USA
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu 879-5593, Japan
| | - DAVID Y. GRAHAM
- Department of Medicine, Gastroenterology and Hepatology Section, Baylor College of Medicine, Houston, Texas 77030, USA
| |
Collapse
|
|
19
|
Systems Biology-Based Investigation of Cellular Antiviral Drug Targets Identified by Gene-Trap Insertional Mutagenesis. PLoS Comput Biol 2016; 12:e1005074. [PMID: 27632082 PMCID: PMC5025164 DOI: 10.1371/journal.pcbi.1005074] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Accepted: 07/22/2016] [Indexed: 02/05/2023] Open
Abstract
Viruses require host cellular factors for successful replication. A comprehensive systems-level investigation of the virus-host interactome is critical for understanding the roles of host factors with the end goal of discovering new druggable antiviral targets. Gene-trap insertional mutagenesis is a high-throughput forward genetics approach to randomly disrupt (trap) host genes and discover host genes that are essential for viral replication, but not for host cell survival. In this study, we used libraries of randomly mutagenized cells to discover cellular genes that are essential for the replication of 10 distinct cytotoxic mammalian viruses, 1 gram-negative bacterium, and 5 toxins. We herein reported 712 candidate cellular genes, characterizing distinct topological network and evolutionary signatures, and occupying central hubs in the human interactome. Cell cycle phase-specific network analysis showed that host cell cycle programs played critical roles during viral replication (e.g. MYC and TAF4 regulating G0/1 phase). Moreover, the viral perturbation of host cellular networks reflected disease etiology in that host genes (e.g. CTCF, RHOA, and CDKN1B) identified were frequently essential and significantly associated with Mendelian and orphan diseases, or somatic mutations in cancer. Computational drug repositioning framework via incorporating drug-gene signatures from the Connectivity Map into the virus-host interactome identified 110 putative druggable antiviral targets and prioritized several existing drugs (e.g. ajmaline) that may be potential for antiviral indication (e.g. anti-Ebola). In summary, this work provides a powerful methodology with a tight integration of gene-trap insertional mutagenesis testing and systems biology to identify new antiviral targets and drugs for the development of broadly acting and targeted clinical antiviral therapeutics. Infectious diseases result in millions of deaths and cost billions of dollars annually. Hence, there is urgency for developing more innovative and effective antiviral therapeutics. In this study, we used libraries of randomly mutagenized cells to discover cellular genes that are essential for the replication of 10 distinct cytotoxic mammalian viruses. We herein reported over 700 candidate cellular genes, over 20% of which were independently selected by multiple viruses in one or more cell types. Using systems biology-based analysis, we found that host genes associated with viral replication tended to occupy central hubs in the human protein interactome and to be ancient genes with low evolutionary rates, compared to non-virus-associated genes. Cell cycle phase-specific sub-network analysis showed that host cell cycle program played important roles during viral replication by regulating specific cell cycle phases. Moreover, we presented novel evidences to suggest that host genes supporting viral replication were frequently implicated in Mendelian and orphan diseases, or played critical roles in cancer. Importantly, we found approximately 110 new putative druggable antiviral targets by merging genome-wide gene-trap insertional mutagenesis, drug-gene network, and bioinformatics data. Furthermore, we have demonstrated the use of a computable representation of genetic testing to effectively identify new potential antiviral indications for existing drugs. In summary, this study presents new and important methodologies for developing broadly active antiviral therapeutics.
Collapse
|
|
20
|
A Nonoligomerizing Mutant Form of Helicobacter pylori VacA Allows Structural Analysis of the p33 Domain. Infect Immun 2016; 84:2662-70. [PMID: 27382020 PMCID: PMC4995914 DOI: 10.1128/iai.00254-16] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 06/24/2016] [Indexed: 12/17/2022] Open
Abstract
Helicobacter pylori secretes a pore-forming VacA toxin that has structural features and activities substantially different from those of other known bacterial toxins. VacA can assemble into multiple types of water-soluble flower-shaped oligomeric structures, and most VacA activities are dependent on its capacity to oligomerize. The 88-kDa secreted VacA protein can undergo limited proteolysis to yield two domains, designated p33 and p55. The p33 domain is required for membrane channel formation and intracellular toxic activities, and the p55 domain has an important role in mediating VacA binding to cells. Previous studies showed that the p55 domain has a predominantly β-helical structure, but no structural data are available for the p33 domain. We report here the purification and analysis of a nonoligomerizing mutant form of VacA secreted by H. pylori The nonoligomerizing 88-kDa mutant protein retains the capacity to enter host cells but lacks detectable toxic activity. Analysis of crystals formed by the monomeric protein reveals that the β-helical structure of the p55 domain extends into the C-terminal portion of p33. Fitting the p88 structural model into an electron microscopy map of hexamers formed by wild-type VacA (predicted to be structurally similar to VacA membrane channels) reveals that p55 and the β-helical segment of p33 localize to peripheral arms but do not occupy the central region of the hexamers. We propose that the amino-terminal portion of p33 is unstructured when VacA is in a monomeric form and that it undergoes a conformational change during oligomer assembly.
Collapse
|
|
21
|
Ricci V. Relationship between VacA Toxin and Host Cell Autophagy in Helicobacter pylori Infection of the Human Stomach: A Few Answers, Many Questions. Toxins (Basel) 2016; 8:toxins8070203. [PMID: 27376331 PMCID: PMC4963836 DOI: 10.3390/toxins8070203] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 06/14/2016] [Accepted: 06/17/2016] [Indexed: 02/06/2023] Open
Abstract
Helicobacter pylori is a Gram-negative bacterium that colonizes the stomach of about half the global population and represents the greatest risk factor for gastric malignancy. The relevance of H. pylori for gastric cancer development is equivalent to that of tobacco smoking for lung cancer. VacA toxin seems to play a pivotal role in the overall strategy of H. pylori towards achieving persistent gastric colonization. This strategy appears to involve the modulation of host cell autophagy. After an overview of autophagy and its role in infection and carcinogenesis, I critically review current knowledge about the action of VacA on host cell autophagy during H. pylori infection of the human stomach. Although VacA is a key player in modulation of H. pylori-induced autophagy, a few discrepancies in the data are also evident and many questions remain to be answered. We are thus still far from a definitive understanding of the molecular mechanisms through which VacA affects autophagy and the consequences of this toxin action on the overall pathogenic activity of H. pylori.
Collapse
Affiliation(s)
- Vittorio Ricci
- Department of Molecular Medicine, Human Physiology Unit, University of Pavia Medical School, Via Forlanini 6, 27100 Pavia, Italy.
| |
Collapse
|
|
22
|
Foegeding NJ, Caston RR, McClain MS, Ohi MD, Cover TL. An Overview of Helicobacter pylori VacA Toxin Biology. Toxins (Basel) 2016; 8:toxins8060173. [PMID: 27271669 PMCID: PMC4926140 DOI: 10.3390/toxins8060173] [Citation(s) in RCA: 147] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Revised: 05/18/2016] [Accepted: 05/27/2016] [Indexed: 12/11/2022] Open
Abstract
The VacA toxin secreted by Helicobacter pylori enhances the ability of the bacteria to colonize the stomach and contributes to the pathogenesis of gastric adenocarcinoma and peptic ulcer disease. The amino acid sequence and structure of VacA are unrelated to corresponding features of other known bacterial toxins. VacA is classified as a pore-forming toxin, and many of its effects on host cells are attributed to formation of channels in intracellular sites. The most extensively studied VacA activity is its capacity to stimulate vacuole formation, but the toxin has many additional effects on host cells. Multiple cell types are susceptible to VacA, including gastric epithelial cells, parietal cells, T cells, and other types of immune cells. This review focuses on the wide range of VacA actions that are detectable in vitro, as well as actions of VacA in vivo that are relevant for H. pylori colonization of the stomach and development of gastric disease.
Collapse
Affiliation(s)
- Nora J Foegeding
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
| | - Rhonda R Caston
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
| | - Mark S McClain
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
| | - Melanie D Ohi
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
- Center for Structural Biology, Vanderbilt University, Nashville, TN 37232, USA.
| | - Timothy L Cover
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
- Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
- Veterans Affairs Tennessee Valley Healthcare System, Nashville, TN 37212, USA.
| |
Collapse
|
|
23
|
Servetas SL, Bridge DR, Merrell DS. Molecular mechanisms of gastric cancer initiation and progression by Helicobacter pylori. Curr Opin Infect Dis 2016; 29:304-10. [PMID: 26779778 PMCID: PMC5144489 DOI: 10.1097/qco.0000000000000248] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PURPOSE OF REVIEW Infection with the Gram-negative, microaerophilic pathogen Helicobacter pylori results in gastric cancer in a subset of infected individuals. As such, H. pylori is the only WHO classified bacterial class I carcinogen. Numerous studies have identified mechanisms by which H. pylori alters host cell signaling pathways to cause disease. The purpose of this review is to highlight recent studies that explore mechanisms associated with induction of gastric cancer. RECENT FINDINGS Over the last year and a half, new mechanisms contributing to the etiology of H. pylori-associated gastric cancer development have been discovered. In addition to utilizing the oncogenic CagA toxin to alter host cell signaling pathways, H. pylori also induces host DNA damage and alters DNA methylation to perturb downstream signaling. Furthermore, H. pylori activates numerous host cell pathways and proteins that result in epithelial-to-mesenchymal transition and induction of cell survival and proliferation. SUMMARY Mounting evidence suggests that H. pylori promotes gastric carcinogenesis using a multifactorial approach. Intriguingly, many of the targeted pathways and mechanisms show commonality with diverse forms of cancer.
Collapse
Affiliation(s)
| | | | - D. Scott Merrell
- Department of Microbiology and Immunology, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, Maryland, 20814, United States of America
| |
Collapse
|
|
24
|
Zhang Y, Sun H, Chen X, Li J, Zhao H, Geng L, Li B. Functional profile of gastric epithelial cells infected with Helicobacter pylori strains. Microb Pathog 2016; 95:77-81. [DOI: 10.1016/j.micpath.2016.03.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 03/21/2016] [Accepted: 03/22/2016] [Indexed: 12/13/2022]
|
|
25
|
Cover TL, Holland RL, Blanke SR. Helicobacter pylori Vacuolating Toxin. HELICOBACTER PYLORI RESEARCH 2016:113-141. [DOI: 10.1007/978-4-431-55936-8_5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2025]
|
|
26
|
Yahiro K, Hirayama T, Moss J, Noda M. Helicobacter pylori VacA toxin causes cell death by inducing accumulation of cytoplasmic connexin 43. Cell Death Dis 2015; 6:e1971. [PMID: 26561781 PMCID: PMC4670933 DOI: 10.1038/cddis.2015.329] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- K Yahiro
- Department of Molecular Infectiology, Graduate School of Medicine, Chiba University, Chiba 260-8670, Japan
| | - T Hirayama
- Department of Bacteriology, Institute of Tropical Medicine, Nagasaki University, Nagasaki 852-8523, Japan
| | - J Moss
- Cardiovascular and Pulmonary Branch, NHLBI, National Institutes of Health, Bethesda, MD 20892, USA
| | - M Noda
- Department of Molecular Infectiology, Graduate School of Medicine, Chiba University, Chiba 260-8670, Japan
| |
Collapse
|
|
27
|
Maes M, Crespo Yanguas S, Willebrords J, Cogliati B, Vinken M. Connexin and pannexin signaling in gastrointestinal and liver disease. Transl Res 2015; 166:332-43. [PMID: 26051630 PMCID: PMC4570182 DOI: 10.1016/j.trsl.2015.05.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 04/29/2015] [Accepted: 05/08/2015] [Indexed: 12/20/2022]
Abstract
Gap junctions, which mediate intercellular communication, are key players in digestive homeostasis. They are also frequently involved in gastrointestinal and liver pathology. This equally holds true for connexin (Cx) hemichannels, the structural precursors of gap junctions, and pannexin (Panx) channels, Cx-like proteins assembled in a hemichannel configuration. Both Cx hemichannels and Panx channels facilitate extracellular communication and drive a number of deteriorative processes, such as cell death and inflammation. Cxs, Panxs, and their channels underlie a wide spectrum of gastrointestinal and liver diseases, including gastritis and peptic ulcer disease, inflammatory intestinal conditions, acute liver failure, cholestasis, hepatitis and steatosis, liver fibrosis and cirrhosis, infectious gastrointestinal pathologies, and gastrointestinal and liver cancer. This could open promising perspectives for the characterization of new targets and biomarkers for therapeutic and diagnostic clinical purposes in the area of gastroenterology and hepatology.
Collapse
Affiliation(s)
- Michaël Maes
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Sara Crespo Yanguas
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Joost Willebrords
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Bruno Cogliati
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of Sao Paulo, Sao Paulo, Brazil
| | - Mathieu Vinken
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium.
| |
Collapse
|
|
28
|
Helicobacter pylori VacA induces apoptosis by accumulation of connexin 43 in autophagic vesicles via a Rac1/ERK-dependent pathway. Cell Death Discov 2015; 1:15035. [PMID: 27551466 PMCID: PMC4979424 DOI: 10.1038/cddiscovery.2015.35] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 08/16/2015] [Accepted: 08/19/2015] [Indexed: 12/15/2022] Open
Abstract
Helicobacter pylori (H. pylori) produces vacuolating cytotoxin (VacA), a potent protein toxin, which is associated with gastric inflammation and ulceration. Recent studies demonstrated that connexins (Cxs), which are responsible for intracellular communication at gap junctions (GJs) as well as cell homeostasis, participate in VacA-induced cell death. We now demonstrate in AZ-521 cells that VacA increased cytoplasmic Cx43, accompanied by LC3-II generation in a time- and dose-dependent manner without induction of Cx43 mRNA expression. Inhibition of VacA-induced Rac1 activity prevented ERK phosphorylation and the increase in Cx43. Suppression of ERK activity and addition of N-acetyl-cysteine inhibited VacA-dependent increase in Cx43 and LC3-II. DIDS, an anion-selective inhibitor, suppressed VacA-dependent increase in Cx43, suggesting that VacA channel activity was involved in this pathway. By confocal microscopy, Cx43 increased by VacA was predominately localized in cholesterol-rich, detergent-resistant membranes including GJs, and a fraction of Cx43 was incorporated in endocytotic vesicles and autophagolysosomes. Accumulation of Cx43 was also observed in gastric mucosa from H. pylori-infected patients compared with healthy controls, suggesting that the pathogen caused a similar effect in vivo. Our findings show that VacA-mediated effects on autophagy inhibits turnover of Cx43, resulting in increased levels in the cytoplasm, leading eventually to apoptotic cell death.
Collapse
|
|
29
|
Abstract
Three decades have passed since Warren and Marshall described the successful isolation and culture of Helicobacter pylori, the Gram-negative bacterium that colonizes the stomach of half the human population worldwide. Although it is documented that H. pylori infection is implicated in a range of disorders of the upper gastrointestinal tract, as well as associated organs, many aspects relating to host colonization, successful persistence, and the pathophysiological mechanisms of this bacteria still remain controversial and are constantly being explored. Unceasing efforts to decipher the pathophysiology of H. pylori infection have illuminated the crucially important contribution of multifarious bacterial factors for H. pylori pathogenesis, in particular the cag pathogenicity island (PAI), the effector protein CagA, and the vacuolating cytotoxin VacA. In addition, recent studies have provided insight into the importance of the gastrointestinal microbiota on the cumulative pathophysiology associated with H. pylori infection. This review focuses on the key findings of publications related to the pathogenesis of H. pylori infection published during the last year, with an emphasis on factors affecting colonization efficiency, cagPAI, CagA, VacA, and gastrointestinal microbiota.
Collapse
Affiliation(s)
| | - Tran Thi Huyen Trang
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, 1-1 Idaigaoka, Hasama-machi, Yufu-City, Oita 879-5593, Japan
| | - Yoshio Yamaoka
- Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, 1-1 Idaigaoka, Hasama-machi, Yufu-City, Oita 879-5593, Japan,Department of Medicine-Gastroenterology, Michael E. DeBakey Veterans Affairs Medical Center and Baylor College of Medicine, Houston, Texas 77030, USA
| |
Collapse
|
|
30
|
Abstract
Helicobacter pylori relies on multiple colonization and virulence factors to persist in the human stomach for life. In addition, these factors can be modulated and vary to suit the ever-changing environment within the host individual. This article outlines the novel developments in this field of research during the past year, highlighting the cag pathogenicity island, VacA, γ-glutamyl-transpeptidase as well as including recent advances in protein structure, bacteria-host interaction, and the role of stomach microbiota.
Collapse
|
|
31
|
Bou Saab J, Losa D, Chanson M, Ruez R. Connexins in respiratory and gastrointestinal mucosal immunity. FEBS Lett 2014; 588:1288-96. [PMID: 24631537 DOI: 10.1016/j.febslet.2014.02.059] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Revised: 02/27/2014] [Accepted: 02/27/2014] [Indexed: 12/18/2022]
Abstract
The mucosal lining forms the physical and chemical barrier that protects against pathogens and hostile particles and harbors its own population of bacteria, fungi and archea, known as the microbiota. The immune system controls tolerance of this population of microorganisms that have proven to be beneficial for its host. Keeping its physical integrity and a correct balance with the microbiota, the mucosa preserves its homeostasis and its protective function and maintains host's health. However, in some conditions, pathogens may succeed in breaching mucosal homeostasis and successfully infecting the host. In this review we will discuss the role the mucosa plays in the defense against bacterial pathogens by considering the gap junction protein connexins. We will detail their implication in mucosal homeostasis and upon infection with bacteria in the respiratory and the gastrointestinal tracts.
Collapse
Affiliation(s)
- Joanna Bou Saab
- Geneva University Hospitals and University of Geneva, Geneva, Switzerland
| | - Davide Losa
- Geneva University Hospitals and University of Geneva, Geneva, Switzerland
| | - Marc Chanson
- Geneva University Hospitals and University of Geneva, Geneva, Switzerland.
| | - Richard Ruez
- Geneva University Hospitals and University of Geneva, Geneva, Switzerland
| |
Collapse
|