iPSCs, and iPSC-EVs were injected intramyocardially at 48 hours after a reperfused myocardial infarction in mice. Compared with vehicle-injected mice, both iPSC-and iPSC-EV-treated mice exhibited improved left ventricular function at 35 d after myocardial infarction, albeit iPSC-EVs rendered greater improvement. iPSC-EV injection also resulted in reduction in left ventricular mass and superior perfusion in the infarct zone.Both iPSCs and iPSC-EVs preserved viable myocardium in the infarct zone, whereas reduction in apoptosis was significant with iPSC-EVs. iPSC injection resulted in teratoma formation, whereas iPSC-EV injection was safe. Conclusions: iPSC-derived

Microvesicles (MVs) are membrane-enclosed cytoplasmic fragments released by normal and activated cells that have been described as important mediators of cell-to-cell communication.Although the ability of human induced pluripotent stem cells (hiPSCs) to participate in tissue repair is being increasingly recognized, the use of hiPSC-derived MVs (hiPSC-MVs) in this regard remains unknown. Accordingly, we investigated the ability of hiPSC-MVs to transfer bioactive molecules including mRNA, microRNA (miRNA), and proteins to mature target cells such as cardiac mesenchymal stromal cells (cMSCs), and we next analyzed effects of hiPSC-MVs on fate and behavior of such target cells. The results show that hiPSC-MVs derived from integration-free hiPSCs cultured under serum-free and feeder-free conditions are rich in mRNA, miRNA, and proteins originated from parent cells; however, the levels of expression vary between donor cells and MVs. Importantly, we found that transfer of hiPSC components by hiPSC-MVs impacted on transcriptome and proteomic profiles of target cells as well as exerted proliferative and protective effects on cMSCs, and enhanced their cardiac and endothelial differentiation potential. hiPSC-MVs also transferred exogenous transcripts from genetically modified hiPSCs that opens new perspectives for future strategies to enhance MV content. We conclude that hiPSC-MVs are effective vehicles for transferring iPSC attributes to adult somatic cells, and hiPSC-MV-mediated horizontal transfer of RNAs and proteins to injured tissues may be used for therapeutic tissue repair. In this study, for the first time, we propose a new concept of use of hiPSCs as a source of safe acellular bioactive derivatives for tissue regeneration. STEM CELLS 2015;33:2748-2761 SIGNIFICANCE STATEMENTOur results show, for the first time, that human induced pluripotent stem cells (hiPS cells) may serve as a source of bioactive microvesicles (MVs) that could be potentially utilized for future safe applications in tissue regeneration. For the first time, we extensively characterized bioactive content of MVs released by hiPS cells (hiPS-MVs) on both transcriptomic and proteomic levels and we established their impact on functions and differentiation potential of mature target cells from human heart. These results have obvious translational relevance for developing potential new iPS cell-based strategies in tissue regeneration by employing thier safe acellular bioactive derivatives.

Growing evidence indicates that intracellular signaling mediated by extracellular vesicles (EVs) released by stem cells plays a considerable role in triggering the regenerative program upon transplantation. EVs from umbilical cord mesenchymal stem cells (UC-MSC-EVs) have been shown to enhance tissue repair in animal models. However, translating such results into clinical practice requires optimized EV collection procedures devoid of animal-originating agents. Thus, in this study, we analyzed the influence of xeno-free expansion media on biological properties of UC-MSCs and UC-MSC-EVs for future applications in cardiac repair in humans. Our results show that proliferation, differentiation, phenotype stability, and cytokine secretion by UC-MSCs vary depending on the type of xeno-free media. Importantly, we found distinct molecular and functional properties of xeno-free UC-MSC-EVs including enhanced cardiomyogenic and angiogenic potential impacting on target cells, which may be explained by elevated concentration of several pro-cardiogenic and pro-angiogenic microRNA (miRNAs) present in the EVs. Our data also suggest predominantly low immunogenic capacity of certain xeno-free UC-MSC-EVs reflected by their inhibitory effect on proliferation of immune cells in vitro. Summarizing, conscious selection of cell culture conditions is required to harvest UC-MSC-EVs with the optimal desired properties including enhanced cardiac and angiogenic capacity, suitable for tissue regeneration.Key message Type of xeno-free media influences biological properties of UC-MSCs in vitro.Certain xeno-free media promote proliferation and differentiation ability of UC-MSCs.EVs collected from xeno-free cultures of UC-MSCs are biologically active.Xeno-free UC-MSC-EVs enhance cardiac and angiogenic potential of target cells.Type of xeno-free media determines immunomodulatory effects mediated by UC-MSC-EVs. Electronic supplementary materialThe online version of this article (doi:10.1007/s00109-016-1471-7) contains supplementary material, which is available to authorized users.

Rhabdomyosarcoma (RMS) is the most common type of pediatric soft tissue sarcoma. The MET receptor has an important role in the biology of RMS, and its overexpression and hyperactivation correlate with the metastatic ability of RMS. Consequently, interfering with MET expression or functionality may constitute a sound strategy for reducing the progression and metastatic potential of RMS. Our study reveals that downregulation of the MET receptor leads to changes in the morphology of ARMS cell in vivo. Tumors acquire a spindle shape that is characteristic of muscle fibers. Inhibition of MET expression or function leads to (i) a decreased expression of the early myogenic marker MyoD, (ii) a decreased ability of ARMS cells to metastasize to bone marrow cavities, (iii) downregulation of CXCR4 receptor expression and (iv) a decreased migration of MET-depleted cells towards gradients of HGF and SDF-1. Finally, we demonstrate that in vitro differentiation of alveolar RMS cells decreases their metastatic behavior by reducing both the expression of the MET and CXCR4 receptors and their migratory response to HGF and SDF-1. These findings suggest that blockers of MET receptor function and inducers of RMS cells differentiation may be clinically useful for reducing the aggressiveness and metastatic potential of RMS and may have significant implications for its treatment.

Cervical cancer is one of the leading causes of death among women suffering from tumors. Current treatment options are insufficient. Here, we investigated the MET receptor as a potential molecular target in advanced cervical cancer. Downregulation of MET receptor expression via RNA interference in different cervical carcinoma cell lines dramatically decreased tumor growth and forced tumor differentiation in vivo. MET receptor silencing also led to a dramatic decrease in cell size and a decrease in proliferation rate under normal and stress conditions. MET receptor downregulation also resulted in decreased cyclin D1 and c-myc levels but did not increase apoptosis. Subsequent experiments showed that downregulation of the MET receptor decreased the expression of a key regulator of the epithelial-to-mesenchymal transition, SLUG. and increased the expression of E-cadherin, a hallmark of the epithelial phenotype. Moreover, MET downregulation impairs expression and signaling of CXCR4 receptor, responsible for invasive phenotype.Taken together, our results strongly suggest that the MET receptor influences the oncogenic properties of cervical carcinoma cells in vitro and in vivo. These findings highlight a unique role of the MET receptor in cervical carcinoma cells and indicate the MET receptor as a potential therapeutic target for advanced cervical carcinoma.

In this study, G-coupled estrogen receptor (GPER) was inactivated, by treatment with antagonist (G-15), in testes of C57BL/6 mice: immature (3 weeks old), mature (3 months old) and aged (1.5 years old) (50 μg/kg bw), as well as MA-10 mouse Leydig cells (10 nM/24 h) alone or in combination with 17β-estradiol or antiestrogen (ICI 182,780). In G-15-treated mice, overgrowth of interstitial tissue was found in both mature and aged testes. Depending on age, differences in structure and distribution of various Leydig cell organelles were observed. Concomitantly, modulation of activity of the mitochondria and tubulin microfibers was revealed. Diverse and complex GPER regulation at the mRNA level and protein of estrogen signaling molecules (estrogen receptor α and β; ERα, ERβ and cytochrome P450 aromatase; P450arom) in G-15 Leydig cells was found in relation to age and the experimental system utilized (in vivo and in vitro). Changes in expression patterns of ERs and P450arom, as well as steroid secretion, reflected Leydig cell heterogeneity to estrogen regulation throughout male life including cell physiological status.We show, for the first time, GPER with ERs and P450arom work in tandem to maintain Leydig cell architecture and supervise its steroidogenic function by estrogen during male life. Full set of estrogen signaling molecules, with involvement of GPER, is crucial for proper Leydig cell function where each molecule acts in a specific and/or complementary manner. Further understanding of the mechanisms by which GPER controls Leydig cells with special regard to male age, cell of origin and experimental system used is critical for predicting and preventing testis steroidogenic disorders based on perturbations in estrogen signaling.

The current evidence suggests that beneficial effects of mesenchymal stem cells (MSCs) toward myocardial repair are largely due to paracrine actions of several factors. Although Monocyte chemoattractant protein-induced protein 1 (MCPIP1) is involved in the regulation of inflammatory response, apoptosis and angiogenesis, whether MCPIP1 plays any role in stem cell-induced cardiac repair has never been examined. By employing retroviral (RV)-transduced overexpression of MCPIP1, we investigated the impact of MCPIP1 on viability, apoptosis, proliferation, metabolic activity, proteome, secretome and differentiation capacity of murine bone marrow (BM) - derived MSCs. MCPIP1 overexpression enhanced angiogenic and cardiac differentiation of MSCs compared with controls as indicated by elevated expression of genes accompanying angiogenesis and cardiomyogenesis in vitro. The proangiogenic activity of MCPIP1-overexpressing MSCs (MCPIP1-MSCs) was also confirmed by increased capillary-like structure formation under several culture conditions. This increase in differentiation capacity was associated with decreased proliferation of MCPIP1-MSCs when compared with controls. MCPIP1-MSCs also expressed increased levels of proteins involved in angiogenesis, autophagy, and induction of differentiation, but not adverse inflammatory agents. We conclude that MCPIP1 enhances endothelial and cardiac differentiation of MSCs. Thus, modulating MCPIP1 expression may be a novel approach useful for enhancing the immune-regulatory, anti-apoptotic, anti-inflammatory and regenerative capacity of BM-derived MSCs for myocardial repair and regeneration of ischemic tissues.

Cervical carcinoma is frequently diagnosed among women, particularly in low and middle income countries. In this study, we investigated the role of the SDF-1/CXCR4 axis during cervical carcinoma growth and progression in vitro and in vivo. Downregulation of CXCR4 receptor using an RNA interference system led to almost complete inhibition of the receptor expression, activation and function. CXCR4 receptor silencing led to decreased ability to signal, to induce migration and to form holoclone-like colonies, with no influence on viability/proliferation of the cells. CXCR4-deficient cells had also significantly lower levels of MMP-9. Interestingly, downregulation of CXCR4 expression resulted in reduced tumor growth in vivo. Tumors generated by CXCR4-deficient cells had also lower expression of the proliferation marker Ki-67 and decreased ability to engraft into lungs and spleen. Taken together, our results indicate that CXCR4 receptor may play an important role during cervical carcinoma invasion. In our study CXCR4 influenced invasive properties of cervical carcinoma cells both in vitro and in vivo.