Bone Marrow Mesenchymal Stem Cells Derived Discoidin Domain-Containing Receptor 2 (DDR2) as a Communication Mediator to Strengthen the Invasiveness and Metastasis of Papillary Thyroid Carcinoma

Our current study plans to dissect the impacts and its underlying mechanisms of bone marrow mesenchymal stem cells (BMSCs) on the invasive and metastatic features of PTC. Clinical specimens from distantly metastatic PTC were collected to measure DRR2 level. After being identified via tri-lineage differentiation and flow cytometry, BMSCs were co-cultured with PTC cells followed by analysis of cell proliferation and migration by CCK-8 and Transwell assays, expression of DDR2 and EMT-associated proteins by Western blot. Eventually, shDDR2-transfected BMSCs were infused with PTC cells into the abdominal cavity of mice to establish a mouse model assess their effect on tumor growth and distant metastasis. DDR2 was upregulated in BMSCs and malignant cells located in the metastatic sites. Co-culture with BMSCs enhanced DRR2 expression in PTC cells, which was simultaneously accompanied by the escalated mesenchymalization process. In vivo experiments exhibited that co-injection with BMSCs facilitated disease progression and distant metastasis of malignancies. Instead, DDR2 knockdown significantly impeded BMSCs-triggered migrative and proliferative behaviors of malignant cells. In conclusion, DDR2 derived from BMSCs can function as a communication mediator to strengthen the invasiveness and metastasis of PTC.

Mesenchymal Stem Cell Immunomodulation: A Novel Intervention Mechanism in Cardiovascular Disease

Mesenchymal stem cells (MSCs) are the member of multipotency stem cells, which possess the capacity for self-renewal and multi-directional differentiation, and have several characteristics, including multi-lineage differentiation potential and immune regulation, which make them a promising source for cell therapy in inflammation, immune diseases, and organ transplantation. In recent years, MSCs have been described as a novel therapeutic strategy for the treatment of cardiovascular diseases because they are potent modulators of immune system with the ability to modulating immune cell subsets, coordinating local and systemic innate and adaptive immune responses, thereby enabling the formation of a stable inflammatory microenvironment in damaged cardiac tissues. In this review, the immunoregulatory characteristics and potential mechanisms of MSCs are sorted out, the effect of these MSCs on immune cells is emphasized, and finally the application of this mechanism in the treatment of cardiovascular diseases is described to provide help for clinical application.

Single Cell Spatial Analysis Reveals the Topology of Immunomodulatory Purinergic Signaling in Glioblastoma

Glioblastoma develops an immunosuppressive microenvironment that fosters tumorigenesis and resistance to current therapeutic strategies. Here we use multiplexed tissue imaging and single-cell RNA-sequencing to characterize the composition, spatial organization, and clinical significance of extracellular purinergic signaling in glioblastoma. We show that glioblastoma exhibit strong expression of CD39 and CD73 ectoenzymes, correlating with increased adenosine levels. Microglia are the predominant source of CD39, while CD73 is principally expressed by tumor cells, particularly in tumors with amplification of EGFR and astrocyte-like differentiation. Spatially-resolved single-cell analyses demonstrate strong spatial correlation between tumor CD73 and microglial CD39, and that their spatial proximity is associated with poor clinical outcomes. Together, this data reveals that tumor CD73 expression correlates with tumor genotype, lineage differentiation, and functional states, and that core purine regulatory enzymes expressed by neoplastic and tumor-associated myeloid cells interact to promote a distinctive adenosine-rich signaling niche and immunosuppressive microenvironment potentially amenable to therapeutic targeting.

Characterization of mesenchymal stem cells isolated from Wharton’s jelly of the human umbilical cord

Background Isolation of post-partum umbilical cord Wharton’s jelly stem cells has gained attention as an alternative source of the bone marrow. Because easy isolation, lack of ethical concerns, and the presence of both embryonic and adult stem cells have made them a valuable source for use in therapeutic applications and regenerative medicine. The study utilized a modified protocol using in-house human pooled cord blood serum for isolation and expansion of the mesenchymal stem cells obtained from the human umbilical cord Wharton’s jelly. Cell proliferation and population doubling time and tri-lineage differentiation were assessed, and the expressions of mesenchymal cell surface markers CD44, CD90, CD105, and CD34 were assessed by flow cytometry and RT-PCR. The genetic stability of the isolated cells was assessed by chromosomal karyotype. Results The isolated cells displayed fibroblastic-like morphology and tri-lineage differentiation into adipocyte, chondrocyte, and osteocyte. The isolated cells maintained the proliferative competence with a doubling time ranged from 38 to 42h and corresponded well with the standard positive and negative molecular markers (CD44+, CD90+, CD 105+, and CD34−). Cell senescence occurred at the later passage of the cells (P15) affecting, about 25% of the population. Metaphases spread of the cells showed normal diploid karyotypes, with typical chromosomal plates indicating genetic stability of the isolated cells. Conclusion The primary cultures exhibited success in isolating the umbilical cord Wharton’s jelly mesenchymal stem cells, which maintained their tri-lineage differentiation potential, phenotypes and karyotype characteristics on further passage and expansion.

Hypoxia Modulates Regenerative Potential of Fetal Stem Cells

Adult mesenchymal stem cells (MSCs) are prone to senescence, which limits the scope of their use in tissue engineering and regeneration and increases the likelihood of post-implantation failure. As a robust alternative cell source, fetal stem cells can prevent an immune reaction and senescence. However, few studies use this cell type. In this study, we sought to characterize fetal cells’ regenerative potential in hypoxic conditions. Specifically, we examined whether hypoxic exposure during the expansion and differentiation phases would affect human fetal nucleus pulposus cell (NPC) and fetal synovium-derived stem cell (SDSC) plasticity and three-lineage differentiation potential. We concluded that fetal NPCs represent the most promising cell source for chondrogenic differentiation, as they are more responsive and display stronger phenotypic stability, particularly when expanded and differentiated in hypoxic conditions. Fetal SDSCs have less potential for chondrogenic differentiation compared to their adult counterpart. This study also indicated that fetal SDSCs exhibit a discrepancy in adipogenic and osteogenic differentiation in response to hypoxia.

Kaposi’s sarcoma-associated herpesvirus vFLIP promotes MEndT to generate hybrid M/E state for tumorigenesis

Kaposi sarcoma (KS) is an angioproliferative and invasive tumor caused by Kaposi sarcoma-associated herpesvirus (KSHV). The cellular origin of KS tumor cells remains contentious. Recently, evidence has accrued indicating that KS may arise from KSHV-infected mesenchymal stem cells (MSCs) through mesenchymal-to-endothelial transition (MEndT), but the transformation process has been largely unknown. In this study, we investigated the KSHV-mediated MEndT process and found that KSHV infection rendered MSCs incomplete endothelial lineage differentiation and formed hybrid mesenchymal/endothelial (M/E) state cells characterized by simultaneous expression of mesenchymal markers Nestin/PDGFRA/α-SAM and endothelial markers CD31/PDPN/VEGFR2. The hybrid M/E cells have acquired tumorigenic phenotypes in vitro and the potential to form KS-like lesions after being transplanted in mice under renal capsules. These results suggest a homology of KSHV-infected MSCs with Kaposi sarcoma where proliferating KS spindle-shaped cells and the cells that line KS-specific aberrant vessels were also found to exhibit the hybrid M/E state. Furthermore, the genetic analysis identified KSHV-encoded FLICE inhibitory protein (vFLIP) as a crucial regulator controlling KSHV-induced MEndT and generating hybrid M/E state cells for tumorigenesis. Overall, KSHV-mediated MEndT that transforms MSCs to tumorigenic hybrid M/E state cells driven by vFLIP is an essential event in Kaposi sarcomagenesis.

Platr4 is an ESC-specific lncRNA that exhibits its function downstream on meso/endoderm lineage commitment

The mammalian genome encodes thousands of long non-coding RNAs (lncRNAs) that are developmentally regulated and differentially expressed across tissues, suggesting possible roles in cellular differentiation. Despite this expression pattern, little is known about how lncRNAs influence lineage commitment at the molecular level. Here, we reveal that perturbation of an embryonic stem cell (ESC)-specific lncRNA, Pluripotency associated transcript 4 (Platr4), in ESCs directly influences the downstream meso/endoderm differentiation program without affecting pluripotency. We further show that Platr4 interacts with the TEA domain transcription factor 4 (Tead4) to regulate the expression of a downstream target gene crucial in the cardiac lineage program known as connective tissue growth factor (Ctgf). Importantly, Platr4 knockout mice exhibit myocardial atrophy, valve mucinous degenration associated with reduced cardiac output and sudden heart failure. Together, our findings provide evidence that Platr4 expression in undifferentiated ESCs is critical for downstream lineage differentiation, highlighting its importance in disease modeling and regenerative medicine.

CHD7 regulates otic lineage differentiation and deafness gene expression in human inner ear organoids

Mutations in the chromatin remodeling enzyme CHD7 cause CHARGE syndrome, which affects multiple organs including the inner ear. We investigated how CHD7 mutations affect otic development in human inner ear organoids. We found loss of CHD7 or its chromatin remodeling activity leads to complete absence of hair cells and supporting cells, which can be explained by dysregulation of key otic development-associated genes in mutant otic progenitors. Further analysis of the mutant otic progenitors suggested that CHD7 can regulate otic genes through a chromatin remodeling-independent mechanism. Results from transcriptome profiling of hair cells revealed disruption of deafness gene expression as a potential underlying mechanism of CHARGE-associated sensorineural hearing loss. Notably, co-differentiating CHD7 knockout and wild-type cells in chimeric organoids partially rescued mutant phenotypes by restoring otherwise severely dysregulated otic genes. Taken together, our results suggest that CHD7 plays a critical role in regulating human otic lineage differentiation and deafness gene expression.

Effects of Various Mineral Trioxide Aggregates on Viability and Mineralization Potential of 3-Dimensional Cultured Dental Pulp Stem Cells

Three-dimensionally (3D) cultured dental pulp stem cells (DPSCs) reportedly exhibit superior multi-lineage differentiation capacities and have a higher expression in regeneration-related gene categories compared to conventionally cultured DPSCs. This study aimed to evaluate the effects of various mineral trioxide aggregates (MTAs) on DPSCs cultured in 3D, assessing their cell viability and tissue mineralization properties. We examined the morphology, cell viability, alkaline phosphate (ALP) activity and qualitative alizarin red S staining assay of the DPSCs that reacted with various MTAs, which included ProRoot (PRM), Biodentine (BIO), and Well-Root PT (WRP), in two different culture plates, an ultra-low attachment plate (ULA) and a conventional monolayer plate (2D). As a control, MTA-free and IRM samples were prepared. None of the MTA groups affected the microsphere-forming characteristics of DPSCs that had been cultured in ULA. The DPSCs that were cultured in ULA showed high cell viability in all MTA groups compared to IRM. The mineralization potential was favorable in all MTA groups, with a significantly higher ALP activity among the DPSCs that were cultured in ULA. Among MTAs, the PRM group showed substantially higher ALP activity than the other MTA groups. In conclusion, our results indicate that 3D-cultured DPSCs with various MTAs showed comparable viability and mineralization capacity similar to those cultured without reacting with MTA cement.