• Clinical outcomes
• Extracellular matrix
• Oncology
• Oncolytic adenovirus
• Recombinant decorin
• Small leucine-rich proteoglycans

• Humans
• Decorin/metabolism
• Decorin/genetics
• Neoplasms/metabolism
• Neoplasms/pathology
• Neoplasms/therapy
• Neoplasms/genetics
• Animals
• Tumor Suppressor Proteins/metabolism
• Tumor Suppressor Proteins/genetics

• CA55819 NCI NIH HHS
• CA200068 U.S. Department of Defense
• National Cancer Institute
• U.S. Department of Defense

• Dormancy
• MTOR2
• Mesenchymal stem cells
• Microenvironment
• Myeloma
• RICTOR

• Humans
• Multiple Myeloma/genetics
• Multiple Myeloma/metabolism
• Neoplasm Recurrence, Local/metabolism
• Mesenchymal Stem Cells/metabolism
• Transcription Factors/metabolism
• Gene Expression Profiling
• Cell Proliferation

• CCN axis
• CCN1-6
• Cancers
• Cellular communication network
• Matricellular

• Bone marrow
• CCN2
• CTGF
• Connective tissue growth factor
• Hematopoiesis
• Leukemogenesis

• bone metastasis
• nanomedicine
• nanotechnology
• prostate cancer

• Antineoplastic Agents/chemistry
• Antineoplastic Agents/therapeutic use
• Bone Neoplasms/diagnosis
• Bone Neoplasms/drug therapy
• Bone Neoplasms/secondary
• Humans
• Male
• Nanomedicine
• Nanotechnology
• Prostatic Neoplasms/diagnosis
• Prostatic Neoplasms/drug therapy

• R01 HL141831 NHLBI NIH HHS

• adipose tissue
• endogenous reservoir
• native mesenchymal stromal cell
• rare cells in circulation
• stroma homeostasis

• Bisphosphonate-related osteonecrosis of the jaw
• Bone remodeling
• Inflammation
• Mechanical load
• Mechanotransduction
• Polydimethylsiloxane

• Animals
• Annexin A5/metabolism
• Bone Remodeling/drug effects
• Bone Resorption/pathology
• Cell Survival/drug effects
• Cytokines/metabolism
• Dimethylpolysiloxanes/pharmacology
• Diphosphonates/pharmacology
• Finite Element Analysis
• Inflammation/pathology
• L-Lactate Dehydrogenase/metabolism
• Mice
• Nitric Oxide Synthase Type II/metabolism
• Osteoblasts/drug effects
• Osteoblasts/metabolism
• Osteoblasts/pathology
• Osteoclasts/drug effects
• Osteoclasts/metabolism
• Osteocytes/drug effects
• Osteocytes/pathology
• Osteogenesis/drug effects
• RAW 264.7 Cells
• Stress, Mechanical
• Tartrate-Resistant Acid Phosphatase/metabolism

• Wharton’s jelly
• osteoblast
• osteoclast
• osteoporosis
• umbilical cord-derived mesenchymal stem cells
• xenograft

• IGFBP2
• adipocytes
• bone marrow
• microenvironment
• myeloma

• Animals
• Antineoplastic Agents/pharmacology
• Antineoplastic Agents/therapeutic use
• Biomarkers
• Bone Diseases/etiology
• Bone Diseases/metabolism
• Bone Diseases/pathology
• Cell Communication
• Cell- and Tissue-Based Therapy
• Humans
• Immunophenotyping
• Mesenchymal Stem Cell Transplantation
• Mesenchymal Stem Cells/drug effects
• Mesenchymal Stem Cells/metabolism
• Molecular Targeted Therapy
• Multiple Myeloma/etiology
• Multiple Myeloma/metabolism
• Multiple Myeloma/pathology
• Multiple Myeloma/therapy
• Signal Transduction
• Tumor Microenvironment

• 5TGM1
• CD4+ T cells
• Multiple myeloma
• PD-1/PD-L1
• bone marrow mesenchymal stem cells

• Animals
• B7-H1 Antigen/antagonists & inhibitors
• B7-H1 Antigen/genetics
• B7-H1 Antigen/immunology
• Bone Marrow Cells/immunology
• Bone Marrow Cells/pathology
• Cell Proliferation
• Coculture Techniques
• Cytokines/genetics
• Cytokines/immunology
• Disease Models, Animal
• Female
• Gene Expression Regulation, Neoplastic
• Lymphocyte Activation
• Mesenchymal Stem Cell Transplantation
• Mesenchymal Stem Cells/immunology
• Mesenchymal Stem Cells/pathology
• Mice
• Mice, Inbred C57BL
• Multiple Myeloma/genetics
• Multiple Myeloma/immunology
• Multiple Myeloma/mortality
• Multiple Myeloma/pathology
• Primary Cell Culture
• Programmed Cell Death 1 Receptor/genetics
• Programmed Cell Death 1 Receptor/immunology
• RNA, Small Interfering/genetics
• RNA, Small Interfering/metabolism
• Signal Transduction/genetics
• Survival Analysis
• T-Lymphocytes, Regulatory/immunology
• T-Lymphocytes, Regulatory/pathology
• Th1 Cells/immunology
• Th1 Cells/pathology
• Th1-Th2 Balance
• Th17 Cells/immunology
• Th17 Cells/pathology
• Th2 Cells/immunology
• Th2 Cells/pathology

Mesenchymal/stromal stem cells (MSCs) are favorably regarded in anti-cancer cytotherapies for their spontaneous chemotaxis toward inflammatory and tumor environments associated with an intrinsic cytotoxicity against tumor cells. Placenta-derived or TRAIL-engineered adipose MSCs have been shown to exert anti-tumor activity in both in-vitro and in-vivo models of multiple myeloma (MM) while TRAIL-transduced umbilical cord (UC)-MSCs appear efficient inducers of apoptosis in a few solid tumors. However, apoptosis is not selective for cancer cells since specific TRAIL receptors are also expressed by a number of normal cells. To overcome this drawback, we propose to transduce UC-MSCs with a bicistronic vector including the TRAIL sequence under the control of IL-6 promoter (pIL6) whose transcriptional activation is promoted by the MM milieu.

UC-MSCs were transduced with a bicistronic retroviral vector (pMIGR1) encoding for green fluorescent protein (GFP) and modified to include the pIL6 sequence upstream of the full-length human TRAIL cDNA. TRAIL expression after stimulation with U-266 cell conditioned medium, or IL-1α/IL-1β, was evaluated by flow cytometry, confocal microscopy, real-time PCR, western blot analysis, and ELISA. Apoptosis in MM cells was assayed by Annexin V staining and by caspase-8 activation. The cytotoxic effect of pIL6-TRAIL⁺-GFP⁺-UC-MSCs on MM growth was evaluated in SCID mice by bioluminescence and ex vivo by caspase-3 activation and X-ray imaging. Statistical analyses were performed by Student’s t test, ANOVA, and logrank test for survival curves.

pIL6-TRAIL⁺-GFP⁺-UC-MSCs significantly expressed TRAIL after stimulation by either conditioned medium or by IL-1α/IL-1β, and induced apoptosis in U-266 cells. Moreover, when systemically injected in SCID mice intratibially xenografted with U-266, those cells underwent within MM tibia lesions and significantly reduced the tumor burden by specific induction of apoptosis in MM cells as revealed by caspase-3 activation.

Our tumor microenvironment-sensitive model of anti-MM cytotherapy is regulated by the axis pIL6/IL-1α/IL-1β and appears suitable for further preclinical investigation not only in myeloma bone disease in which UC-MSCs would even participate to bone healing as described, but also in other osteotropic tumors whose milieu is enriched of cytokines triggering the pIL6.

• Apoptosis
• Multiple myeloma
• TRAIL
• Umbilical cord mesenchymal stromal/stem cells

Haematopoiesis is the term used to describe the production of blood cells. This is a tightly regulated hierarchical system in which mature circulating blood cells develop from a small population of haematopoietic stem (HSC) and progenitor cells within the microenvironment of the bone marrow. Molecular and genetic abnormalities arising in these stem cells lead to a block in the normal programme of proliferation and differentiation and result in the development of the blood cancers known as the leukaemias and lymphomas. Recently the regulatory role of the bone marrow microenvironment or niche has also become increasingly recognised. The interface between the bone and bone marrow (endosteum) and the region surrounding the blood vessels (perivascular) provide distinct niches harbouring quiescent HSC or proliferative HSC respectively. Current chemotherapeutic regimes can often successfully target the proliferative HSC but disease relapse occurs due to residual quiescent HSC. Understanding these developmental and regulatory processes and the associated cell communication mechanisms are thus crucial to the development of new treatment strategies. The CCN family of proteins have been recognised to play a key role in all aspects of haematopoiesis.

• Blood cancer
• Bone marrow microenvironment
• Haematopoiesis
• Leukaemia
• Lymphoma
• Stem cells

• RPMI 8226 cells
• mesenchymal stromal cells (MSCs)
• multiple myeloma (MM)
• paclitaxel
• rotary cell culture system (RCCS) bioreactor

Multiple myeloma is largely incurable, despite development of therapies that target myeloma cell-intrinsic pathways. Disease relapse is thought to originate from dormant myeloma cells, localized in specialized niches, which resist therapy and repopulate the tumour. However, little is known about the niche, and how it exerts cell-extrinsic control over myeloma cell dormancy and reactivation. In this study, we track individual myeloma cells by intravital imaging as they colonize the endosteal niche, enter a dormant state and subsequently become activated to form colonies. We demonstrate that dormancy is a reversible state that is switched ‘on' by engagement with bone-lining cells or osteoblasts, and switched ‘off' by osteoclasts remodelling the endosteal niche. Dormant myeloma cells are resistant to chemotherapy that targets dividing cells. The demonstration that the endosteal niche is pivotal in controlling myeloma cell dormancy highlights the potential for targeting cell-extrinsic mechanisms to overcome cell-intrinsic drug resistance and prevent disease relapse.

Therapy resistant dormant myeloma cells contribute to disease relapse. Here, the authors use intravital microscopy to track the location of these cells and demonstrate that they hone to the endosteal niche within the bone.

• Bone microenvironment
• Multiple myeloma
• Therapeutic opportunities

• Adult
• Aged
• Antineoplastic Agents/therapeutic use
• Bone Marrow/metabolism
• Bone Marrow/pathology
• Bone Marrow Cells/metabolism
• Cell Proliferation
• Cytokines/metabolism
• Decorin/metabolism
• Disease-Free Survival
• Enzyme-Linked Immunosorbent Assay
• Extracellular Matrix/metabolism
• Female
• Humans
• Induction Chemotherapy/methods
• Male
• Middle Aged
• Multiple Myeloma/drug therapy
• Multiple Myeloma/mortality
• Multiple Myeloma/pathology
• Retrospective Studies
• Treatment Outcome
• Young Adult

• CCN
• Cancer
• Haematopoietic stem cell (HSC)
• Mesenchymal stem cell (MSC)

• Bisphosphonate-related osteonecrosis
• Conditioned media
• Osteoclasts
• Osteogenesis
• Paracrine effects
• Secretome

• Animals
• Apoptosis/drug effects
• Biomarkers/metabolism
• Bisphosphonate-Associated Osteonecrosis of the Jaw/diagnostic imaging
• Bisphosphonate-Associated Osteonecrosis of the Jaw/drug therapy
• Bisphosphonate-Associated Osteonecrosis of the Jaw/pathology
• Cell Differentiation/drug effects
• Cell Survival/drug effects
• Culture Media, Conditioned/pharmacology
• Dexamethasone/pharmacology
• Diphosphonates/adverse effects
• Disease Models, Animal
• Gene Expression Regulation/drug effects
• Humans
• Imidazoles/adverse effects
• Injections
• Intercellular Signaling Peptides and Proteins/pharmacology
• Male
• Mesenchymal Stem Cells/drug effects
• Mesenchymal Stem Cells/metabolism
• Neovascularization, Physiologic/drug effects
• Neovascularization, Physiologic/genetics
• Osteoclasts/drug effects
• Osteoclasts/metabolism
• Osteoclasts/pathology
• Osteogenesis/drug effects
• Osteogenesis/genetics
• Radiography
• Rats, Wistar
• Real-Time Polymerase Chain Reaction
• Zoledronic Acid

• Inflammation
• Intravital imaging
• Mesenchymal stem cells
• Neutrophils
• Platelets
• Trafficking

• Animals
• Blood Platelets/cytology
• Blood Platelets/metabolism
• Cell Adhesion/physiology
• Cell Movement/physiology
• Humans
• Mesenchymal Stem Cells/cytology
• Mesenchymal Stem Cells/diagnostic imaging
• Mice
• Mice, Inbred C57BL
• Microscopy, Confocal/methods
• Neutrophils/cytology
• Neutrophils/metabolism
• Radiography

• P40RR017447 NCRR NIH HHS
• P41 EB015903 NIBIB NIH HHS
• U01 HL100402 NHLBI NIH HHS
• HL095722 NHLBI NIH HHS
• R21 HL097172 NHLBI NIH HHS
• P40 RR017447 NCRR NIH HHS
• R01 HL095722 NHLBI NIH HHS
• P41 EB015903-02S1 NIBIB NIH HHS
• R01 EB017274 NIBIB NIH HHS
• R01 HL104006 NHLBI NIH HHS
• HL104006 NHLBI NIH HHS

In an effort to develop a new therapy for prostate cancer bone metastases, we have created Ad.dcn, a recombinant oncolytic adenovirus carrying the human decorin gene. Infection of PC-3 and DU-145, the human prostate tumor cells, with Ad.dcn or a non-replicating adenovirus Ad(E1-).dcn resulted in decorin expression; Ad.dcn produced high viral titers and cytotoxicity in human prostate tumor cells. Adenoviral-mediated decorin expression inhibited Met, the Wnt/β-catenin signaling axis, vascular endothelial growth factor A, reduced mitochondrial DNA levels, and inhibited tumor cell migration. To examine the anti-tumor response of Ad.dcn, PC-3-luc cells were inoculated in the left heart ventricle to establish bone metastases in nude mice. Ad.dcn, in conjunction with control replicating and non-replicating vectors were injected via tail vein. The real-time monitoring of mice, once a week, by bioluminescence imaging and X-ray radiography showed that Ad.dcn produced significant inhibition of skeletal metastases. Analyses of the mice at the terminal time point indicated a significant reduction in the tumor burden, osteoclast number, serum TRACP 5b levels, osteocalcin levels, hypercalcemia, inhibition of cancer cachexia, and an increase in the animal survival. Based on these studies, we believe that Ad.dcn can be developed as a potential new therapy for prostate cancer bone metastasis.

Multiple myeloma is a common hematological malignancy that leads to the occurrence of bone lesions. The combination of traditional cytotoxic and novel agents is usually taken to treat multiple myeloma-related bone diseases. However, the curative effect is not very satisfactory. Stem cell-based therapy has been recently introduced and investigated, which represents a new frontier in the treatment of multiple myeloma. In a recent interesting study, Dr Atsuta and colleagues provide a new insight into the effects of mesenchymal stem cells on multiple myeloma via Fas/Fas ligand pathway, which rekindles the fire of hope for those patients suffering from multiple myeloma.

Cell-based therapy represents a new frontier in the treatment of a wide variety of human diseases traditionally associated with morbidity outcomes, including those involving inflammation, autoimmunity, tissue damage, and cancer. However, the use of mesenchymal stem cells (MSCs) to treat multiple myeloma (MM) bone disease has raised concerns. Specifically, evidence has shown that infused MSCs might support tumor growth and metastasis.

In this study, we used a standard disseminated MM model in mice to identify the in vivo effects of intravenous MSC infusion. In addition, a series of in vitro co-culture assays were preformed to explore whether Fas/Fas ligand (Fas-L) is involved in the inhibitory effects of MSCs on MM cells.

In the MM mouse model, treatment of MSCs with highly expressed Fas ligand (Fas-L^high MSCs) showed remarkable inhibitory effects on MM indenization in terms of extending the mouse survival rate and inhibiting tumor growth, bone resorption in the lumbus and collum femoris, and MM cell metastasis in the lungs and kidneys. In addition, reduced proliferation and increased apoptosis of MM cells was observed when co-cultured with Fas-L^high MSCs in vitro. Furthermore, mechanistically, the binding between Fas and Fas-L significantly induced apoptosis in MM cells, as evidenced through an increase in the expression of apoptosis marker and Fas in MM cells. In contrast, Fas-L^null MSCs promote MM growth.

These data suggest that Fas/Fas-L-induced MM apoptosis plays a crucial role in the MSC-based inhibition of MM growth. Although whether MSCs inhibit or promote cancer growth remains controversial, the levels of Fas-L expression in MSCs determine, at least partially, the effects of MSCs on MM cell growth.

Multiple myeloma is a hematological malignancy in which clonal plasma cells proliferate and accumulate within the bone marrow. The presence of osteolytic lesions due to increased osteoclast (OC) activity and suppressed osteoblast (OB) function is characteristic of the disease. The bone marrow mesenchymal stromal cells (MSCs) play a critical role in multiple myeloma pathophysiology, greatly promoting the growth, survival, drug resistance and migration of myeloma cells. Here, we specifically discuss on the relative contribution of MSCs to the pathophysiology of osteolytic lesions in light of the current knowledge of the biology of myeloma bone disease (MBD), together with the reported genomic, functional and gene expression differences between MSCs derived from myeloma patients (pMSCs) and their healthy counterparts (dMSCs). Being MSCs the progenitors of OBs, pMSCs primarily contribute to the pathogenesis of MBD because of their reduced osteogenic potential consequence of multiple OB inhibitory factors and direct interactions with myeloma cells in the bone marrow. Importantly, pMSCs also readily contribute to MBD by promoting OC formation and activity at various levels (i.e., increasing RANKL to OPG expression, augmenting secretion of activin A, uncoupling ephrinB2-EphB4 signaling, and through augmented production of Wnt5a), thus further contributing to OB/OC uncoupling in osteolytic lesions. In this review, we also look over main signaling pathways involved in the osteogenic differentiation of MSCs and/or OB activity, highlighting amenable therapeutic targets; in parallel, the reported activity of bone-anabolic agents (at preclinical or clinical stage) targeting those signaling pathways is commented.

• Mesenchymal stromal cells
• Multiple myeloma
• Osteolytic lesions
• Myeloma bone disease
• Bone-directed therapy
• Bone-anabolic drugs

CCN family member 1 (CCN1), also known as cysteine-rich angiogenic inducer 61 (CYR61), belongs to the extracellular matrix-associated CCN protein family. The diverse functions of these proteins include regulation of cell migration, adhesion, proliferation, differentiation and survival/apoptosis, induction of angiogenesis and cellular senescence. Their functions are partly overlapping, largely non-redundant, cell-type specific, and depend on the local microenvironment. To elucidate the role of CCN1 in the crosstalk between stromal cells and myeloma cells, we performed co-culture experiments with primary mesenchymal stem cells (MSC) and the interleukin-6 (IL-6)-dependent myeloma cell line INA-6. Here we show that INA-6 cells display increased transcription and induction of splicing of intron-retaining CCN1 pre-mRNA when cultured in contact with MSC. Protein analyses confirmed that INA-6 cells co-cultured with MSC show increased levels of CCN1 protein consistent with the existence of a pre-mature stop codon in intron 1 that abolishes translation of unspliced mRNA. Addition of recombinant CCN1-Fc protein to INA-6 cells was also found to induce splicing of CCN1 pre-mRNA in a concentration-dependent manner. Only full length CCN1-Fc was able to induce mRNA splicing of all introns, whereas truncated recombinant isoforms lacking domain 4 failed to induce intron splicing. Blocking RGD-dependent integrins on INA-6 cells resulted in an inhibition of these splicing events. These findings expand knowledge on splicing of the proangiogenic, matricellular factor CCN1 in the tumor microenvironment. We propose that contact with MSC-derived CCN1 leads to splicing and enhanced transcription of CCN1 which further contributes to the translation of angiogenic factor CCN1 in myeloma cells, supporting tumor viability and myeloma bone disease.

Multiple myeloma (MM) is characterized by advanced osteolytic lesions resulting from the activation of osteoclasts (OCs) and inhibition of osteoblasts (OBs). OBs are derived from mesenchymal stem cells (MSCs) from the bone marrow (BM), however the pool and function of BMMSCs in MM patients (MM-BMMSCs) are reduced by myeloma cells (MCs) and cytokines secreted from MCs and related anti-MM treatment. Such reduction in MM-BMMSCs currently cannot be restored by any means. Recently, genetic aberrations of MM-BMMSCs have been noted, which further impaired their differentiation toward OBs. We hypothesize that the MSCs derived from adipose tissue (ADMSCs) can be used as alternative MSC sources to enhance the pool and function of OBs. Therefore, the purpose of this study was to compare the osteogenesis ability of paired ADMSCs and BMMSCs in MM patients who had completed intensive therapy. Fifteen MM patients who had received bortezomib-based induction and autologous transplantation were enrolled. At the third month after the transplant, the paired ADMSCs and BMMSCs were obtained and cultured. Compared with the BMMSCs, the ADMSCs exhibited a significantly higher expansion capacity (100% vs 13%, respectively; P = .001) and shorter doubling time (28 hours vs 115 hours, respectively; P = .019). After inducing osteogenic differentiation, although the ALP activity did not differ between the ADMSCs and BMMSCs (0.78 U/µg vs 0.74±0.14 U/µg, respectively; P = .834), the ADMSCs still exhibited higher calcium mineralization, which was determined using Alizarin red S (1029 nmole vs 341 nmole, respectively; P = .001) and von Kossa staining (2.6 E+05 µm² vs 5 E+04 µm², respectively; P = .042), than the BMMSCs did. Our results suggested that ADMSCs are a feasible MSC source for enhancing the pool and function of OBs in MM patients who have received intensive therapy.

• Adipose Tissue/cytology
• Adult
• Aged
• Antineoplastic Agents/therapeutic use
• Antineoplastic Combined Chemotherapy Protocols
• Bone Marrow Cells/pathology
• Boronic Acids/therapeutic use
• Bortezomib
• Cell Differentiation
• Cell Proliferation
• Cells, Cultured
• Cycloheximide/administration & dosage
• Dexamethasone/administration & dosage
• Female
• Hematopoietic Stem Cell Transplantation
• Humans
• Male
• Mesenchymal Stem Cells/cytology
• Middle Aged
• Multiple Myeloma/immunology
• Multiple Myeloma/pathology
• Multiple Myeloma/therapy
• Osteoblasts/cytology
• Osteoblasts/transplantation
• Osteogenesis
• Pyrazines/therapeutic use
• Remission Induction
• Thalidomide/administration & dosage
• Transplantation, Autologous

Osteoporosis is a skeletal disease leading to an increased risk of bone fracture. Using a mouse osteoporosis model induced by administration of a receptor activator of nuclear factor kappa-B ligand (RANKL), salubrinal was recently reported as a potential therapeutic agent. To evaluate the role of salubrinal in cellular fates as well as migratory and adhesive functions of osteoclast/osteoblast precursors, we examined the development of primary bone marrow-derived cells in the presence and absence of salubrinal. We addressed a question: are salubrinal’s actions more potent to the cells isolated from the osteoporotic mice than those isolated from the control mice?

Using the RANKL-injected and control mice, bone marrow-derived cells were harvested. Osteoclastogenesis was induced by macrophage-colony stimulating factor and RANKL, while osteoblastogenesis was driven by dexamethasone, ascorbic acid, and β-glycerophosphate.

The results revealed that salubrinal suppressed the numbers of colony forming-unit (CFU)-granulocyte/macrophages and CFU-macrophages, as well as formation of mature osteoclasts in a dosage-dependent manner. Salubrinal also suppressed migration and adhesion of pre-osteoclasts and increased the number of CFU-osteoblasts. Salubrinal was more effective in exerting its effects in the cells isolated from the RANKL-injected mice than the control. Consistent with cellular fates and functions, salubrinal reduced the expression of nuclear factor of activated T cells c1 (NFATc1) as well as tartrate-resistant acid phosphatase.

The results support the notion that salubrinal exhibits significant inhibition of osteoclastogenesis as well as stimulation of osteoblastogenesis in bone marrow-derived cells, and its efficacy is enhanced in the cells harvested from the osteoporotic bone samples.