SRC3 expressed in bone marrow mesenchymal stem cells promotes the development of multiple myeloma

The role of mesenchymal stem cells in the treatment and pathogenesis of psoriasis

Psoriasis, a prevalent inflammatory skin condition impacting millions globally, continues to pose treatment challenges, despite the availability of multiple therapies. This underscores the demand for innovative treatments. Mesenchymal stem cells (MSCs) have emerged as a promising therapeutic option due to their capacity to modulate the immune system and facilitate tissue healing. Recent research indicates that MSCs don't just work through direct cell-to-cell interactions but also release extracellular vesicles (EVs), containing various bioactive substances like proteins, lipids, and nucleic acids. This article explores our current knowledge of psoriasis's origins and the potential utilization of MSCs and their EVs, particularly exosomes, in managing the condition. Additionally, we delve into how MSCs and EVs function in therapy, including their roles in regulating immune responses and promoting tissue repair. Lastly, we discuss the obstacles and opportunities associated with translating MSC-based treatments for psoriasis into clinical practice.

Mesenchymal stem cells and their extracellular vesicles as emerging therapeutic tools in the treatment of ischemic stroke

Ischemic stroke (IS) is a neurological condition characterized by severe long-term consequences and an unfavorable prognosis for numerous patients. Despite advancements in stroke treatment, existing therapeutic approaches possess certain limitations. However, accumulating evidence suggests that mesenchymal stem/stromal cells (MSCs) hold promise as a potential therapy for various neurological disorders, including IS, owing to their advantageous properties, such as immunomodulation and tissue regeneration. Additionally, MSCs primarily exert their therapeutic effects through the release of extracellular vesicles (EVs), highlighting the significance of their paracrine activities. These EVs are small double-layered phospholipid membrane vesicles, carrying a diverse cargo of proteins, lipids, and miRNAs that enable effective cell-to-cell communication. Notably, EVs have emerged as attractive substitutes for stem cell therapy due to their reduced immunogenicity, lower tumorigenic potential, and ease of administration and handling. Hence, this review summarizes the current preclinical and clinical studies performed to investigate the safety and therapeutic potential of MSCs and their EVs derived from different sources, including bone marrow, adipose tissue, umbilical cord blood, and Wharton's jelly in IS.

MiR-182-5p Mediated by Exosomes Derived From Bone Marrow Mesenchymal Stem Cell Attenuates Inflammatory Responses by Targeting TLR4 in a Mouse Model of Myocardial Infraction

Exosomes derived from mesenchymal stem cells (MSCs) could protect against myocardial infarction (MI). TLR4 is reported to play an important role in MI, while microRNA-182-5p (miR-182-5p) negatively regulates TLR4 expression. Therefore, we hypothesize that MSCs-derived exosomes overexpressing miR-182-5p may have beneficial effects on MI. We generated bone marrow mesenchymal stem cells (BM-MSCs) and overexpressed miR-182-5p in these cells for exosome isolation. H₂O₂-stimulated neonatal mouse ventricle myocytes (NMVMs) and MI mouse model were employed, which were subjected to exosome treatment. The expression of inflammatory factors, heart function, and TLR4 signaling pathway activation were monitored. It was found that miR-182-5p decreased TLR4 expression in BM-MSCs and NMVMs. Administration of exosomes overexpressing miR-182-5p to H₂O₂-stimulated NMVMs enhanced cell viability and suppressed the expression of inflammatory cytokines. In addition, they promoted heart function, suppressed inflammatory responses, and de-activated TLR4/NF-κB signaling pathway in MI mice. In conclusion, miR-182-5p transferred by the exosomes derived from BM-MSCs protected against MI-induced impairments by targeting TLR4.

Bone marrow-derived mesenchymal stem cells overexpressed with miR-182-5p protects against brain injury in a mouse model of cerebral ischemia

BACKGROUND

Toll-like receptor 4 (TLR4) plays a critical role in ischemic brain injury by mediating the inflammatory response. The microRNA miR-185-5p suppresses inflammatory signaling by targeting TLR4. This study investigates whether overexpressing miR-182-5p in bone marrow-derived mesenchymal stem cells (BM-MSCs) could potentiate the neuroprotective effects of BM-MSCs in a mouse model of ischemic brain injury.

METHODS

We isolated BM-MSCs from mice, transfected the cells with miR-182-5p mimic, determined their MSC lineage through flow cytometry analysis of surface markers, examined miR-182-5p and TLR4 expression levels, and injected them into mice undergone middle cerebral artery occlusion (MCAO). MSC transplanted mice were subjected to behavior assays to determine cognitive and motor functions and biochemical analysis to determine neuroinflammation and TLR4/NF-κB in the ischemic hemisphere.

RESULTS

We found that BM-MSCs overexpressing miR-182-5p showed reduced TLR4 expression without affecting their MSC lineage. Mice transplanted with miR-182-5p overexpressing BM-MSCs after MCAO showed significantly improved cognitive and motor functions and reduced neuroinflammation, including suppressed microglial M1 polarization, reduced inflammatory cytokines, and inhibited TLR4/ NF-κB signaling.

CONCLUSION

Our findings suggest that overexpressing miR-182-5p in BM-MSCs can enhance the neuroprotective effects of BM-MSCs against ischemic brain injury by suppressing TLR4-mediated inflammatory response.

Exosomal miR-483-5p in Bone Marrow Mesenchymal Stem Cells Promotes Malignant Progression of Multiple Myeloma by Targeting TIMP2

Bone marrow-derived mesenchymal stem cell (BMSC) is one crucial component of the multiple myeloma (MM) microenvironment and supports the malignant progression of MM. Whether BMSCs act on MM cells via exosomes has not been well characterized. Herein, we used microarrays to screen out differentially expressed miRNAs in BMSCs from patients with MM (MM-MSCs) or benign diseases (BD-MSCs). We found that miR-483-5p was highly expressed in MM-MSCs, which may be transported through exosomes from MM-MSCs to MM cells to increase miR-483-5p expression in them. We then investigated the role and mechanism of miR-483-5p in the aggressive progression of MM in vitro. We verified that miR-483-5p promoted MM cell proliferation and reduced apoptosis. Then we predicted and validated that TIMP2, a tumor suppressor gene, is the downstream target of miR-483-5p in MM. In summary, our study indicated that MM-MSCs promote MM malignant progression via the release of exosomes and regulation of miR-483-5p/TIMP2 axis, suggesting an essential role of BMSCs derived exosomal miRNA in MM and a potential marker for MM diagnosis and therapy.

SRC3 Promotes the Protective Effects of Bone Marrow Mesenchymal Stem Cell Transplantation on Cerebral Ischemia in a Mouse Model

Mesenchymal stem cells (MSCs) derived from the bone marrow (BM) are reported to protect against ischemic brain injury. This study aimed to investigate whether the steroid receptor cofactor 3 (SRC3) was involved in MSC-induced neuroprotection. BM-MSCs were isolated from wild-type (WT) and SRC3 knockout (SRC3^-/-) mice and transplanted into mice with middle cerebral artery occlusion (MCAO). The MSC identification and differentiation were determined by flow cytometry and Alizarin Red S staining after osteogenic and adipogenic stimulations. The effects of MSCs on brain injury were assessed by brain water content, modified neurological severity score (mNSS), Morris water maze test, and open field test. Finally, the effects of MSCs on MCAO-induced oxidative stress were assessed by measuring the levels of malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD) and mRNA levels of SOD1, SOD2, and CAT. We found that SRC3 deficiency did not impact the MSC identification or osteogenic and adipogenic differentiation. MSC-SRC3^-/- transplantation in mice that underwent the MCAO procedure exhibited diminished effects on suppression of brain edema, neurological deficits, cognitive disruption, locomotor impairment, and anxiety compared to comparable levels of MSC-WT. Finally, MSC-WT transplantation inhibited MCAO-induced oxidative stress, and the effects were significantly attenuated in MCAO mice transplanted with MSC-SRC3^-/-. MSCs suppressed the MCAO-induced upregulation of MDA activity and the inhibition of SOD, GSH, SOD1, SOD2, and CAT levels, and SRC3-deficient MSCs showed significantly reduced effects. Our results indicate that SRC3 plays an important role in mediating the neuroprotective effects of MSCs in mice that experienced ischemic stroke.

Exosomes derived from miR-129-5p modified bone marrow mesenchymal stem cells represses ventricular remolding of mice with myocardial infarction

Myocardial infraction (MI) is a severe disease with great mortality. Mesenchymal stem cells-derived exosomes display protection against MI. MicroRNA-129-5p was reported to exert anti-inflammation activity by targeting high mobility group box 1 (HMGB1). In the present study, the effects of MSCs derived exosomes overexpressing miR-129-5p on MI were evaluated. Bone marrow mesenchymal stem cells (BMSCs) were transfected with miR-129-5p for exosomes isolation. Myocardial infraction mice model was established and administrated exosomes overexpressing miR-129-5p. The cardiac function, expression of HMGB1, inflammatory cytokines, apoptosis and fibrosis in heart tissues were measured. miR-129-5p inhibited HMGB1 expression in BMSCs. Myocardial infraction mice treated with exosomes overexpressing miR-129-5p had enhanced cardiac function and decreased expression of HMGB1 and production of inflammatory cytokines. Exosomes overexpressing miR-129-5p further prevented apoptosis and fibrosis. Exosome-mediated transfer of miR-129-5p suppressed inflammation in MI mice by targeting HMGB1.

Can Targeting Hypoxia-Mediated Acidification of the Bone Marrow Microenvironment Kill Myeloma Tumor Cells?

Multiple myeloma (MM) is an incurable cancer arising from malignant plasma cells that engraft in the bone marrow (BM). The physiology of these cancer cells within the BM microenvironment (TME) plays a critical role in MM development. These processes may be similar to what has been observed in the TME of other (non-hematological) solid tumors. It has been long reported that within the BM, vascular endothelial growth factor (VEGF), increased angiogenesis and microvessel density, and activation of hypoxia-induced transcription factors (HIF) are correlated with MM progression but despite a great deal of effort and some modest preclinical success the overall clinical efficacy of using anti-angiogenic and hypoxia-targeting strategies, has been limited. This review will explore the hypothesis that the TME of MM engrafted in the BM is distinctly different from non-hematological-derived solid tumors calling into question how effective these strategies may be against MM. We further identify other hypoxia-mediated effectors, such as hypoxia-mediated acidification of the TME, oxygen-dependent metabolic changes, and the generation of reactive oxygen species (ROS), that may prove to be more effective targets against MM.

Correlation of A-Kinase Interacting Protein 1 With Clinical Features, Treatment Response, and Survival Profiles in Patients With Multiple Myeloma

Objective:

The present study aimed to detect A-kinase interacting protein 1 expression and further explore the association of A-kinase interacting protein 1 with clinical features and prognosis in patients with multiple myeloma.

Methods:

Totally, 152 de novo symptomatic patients with multiple myeloma and 30 healthy donors were enrolled. Bone marrow mononuclear cells derived plasma cells were collected from patients with multiple myeloma before initial treatment and from healthy donors on the enrollment, respectively, and then A-kinase interacting protein 1 protein/messenger RNA expressions were detected by Western blot and reverse transcription quantitative polymerase chain reaction. Treatment response (complete response and overall response rate) was assessed, and survival profiles (progression-free survival and overall survival) were calculated in patients with multiple myeloma.

Results:

A-kinase interacting protein 1 protein/messenger RNA expressions were elevated in patients with multiple myeloma compared to healthy donors, and A-kinase interacting protein 1 (area under the curve: 0.809, 95% confidence interval: 0.726-0.891)/messenger RNA (area under the curve: 0.839, 95% confidence interval: 0.764-0.914) presented good value in differentiating patients with multiple myeloma from healthy donors. In patients with multiple myeloma, A-kinase interacting protein 1 /messenger RNA expressions negatively correlated with albumin while positively correlated with Beta-2-microglobulin, lactate dehydrogenase, International Staging System stage, and t (4;14). Meanwhile, there were 39 (25.7%) complete response patients, 113 (74.3%) noncomplete response patients, 112 (73.7%) overall response rate patients, and 40 (26.3%) nonoverall response rate patients. Complete response and overall response rates were decreased in patients with high A-kinase interacting protein 1 compared to patients with low A-kinase interacting protein 1. Additionally, progression-free survival and overall survival were reduced in patients with high A-kinase interacting protein 1 compared to patients with low A-kinase interacting protein 1.

Conclusion:

A-kinase interacting protein 1 exhibits the potency as a biomarker for multiple myeloma progression and prognosis, which implies the clinical application of A-kinase interacting protein 1 in multiple myeloma management.

Patent highlights February–March 2020

A snapshot of noteworthy recent developments in the patent literature of relevance to pharmaceutical and medical research and development.