Pancreatic tissue engineering as a therapeutic option for restoring and maintenance of damaged pancreas function has a special focus to using synthetic Scaffolds. This study was designed to evaluate pancreatic differentiation of human induced pluripotent stem cells (hiPSCs) on poly-L-lactic acid and polyvinyl alcohol (PLLA/PVA) scaffolds as 3 D matrix. During differentiation process, morphology of cells gradually changed and iPSCs derived insulin producing cells (iPSCs-IPCs) formed spherical shaped cell aggregation that was the typical shape of islets of pancreas. The highly efficient differentiation of iPSCs into a relatively homogeneous population of IPCs was shown by immunostaining. Real-time reverse transcription polymerase chain reaction (RT-PCR) results demonstrated that iPSCs-IPCs expressed pancreas-specific transcription factors (Pdx1, insulin, glucagon and Ngn3). The expressions of these transcription factors in PLLA/PVA scaffold were significantly higher than 2 D groups. Furthermore, we showed that concentration of insulin and C-peptide in PLLA/PVA scaffold and/or 2 D culture in response to various concentrations of glucose increased but the difference between them were not significant. Altogether the current results demonstrated that PLLA/PVA scaffold could provide the microenvironment that promotes the pancreatic differentiation of iPSCs, up-regulate pancreatic-specific transcription factors and improved metabolic activity.

Studies on patient-specific human-induced pluripotent stem cells (hiPSCs) as well as a series of autologous growth factors presumably will reveal their many benefits for cell base replacement therapy in type 1 diabetes mellitus (TIDM) patients in the future. For this purpose, we established a multistep protocol by adding platelet-rich plasma (PRP) that induce the hiPSCs into insulin-producing cells (IPCs). We present here a differentiation protocol consisting of five stages in two groups including protocol with PRP and without PRP. Charac-teristics of derived IPCs in both groups were evaluated at the mRNA and protein levels, cell cycle and viability in the end stage of cell differentiation. The in vitro studies indicated the treatment of hiPSCs in the protocol with PRP resulting in differentiated cells with strong characteristics of IPCs including islet-like cells, the expression of mature and functional pancreatic beta cell specific marker genes. In addition to these pancreatic specific markers were detected by immunochemistry and Western blot. Our differentiated cells in two groups secreted insulin and C-peptide in a glucose stimulation test by ELISA showing in vitro functional. The results of the cell cycle assay confirmed that differentiation has been done. We reported for the first time that PRP might be ideal additive in the culture medium to induce pancreatic differentiation in the hiPSCs. This study provides a new approach to investigate the role of PRP in pancreatic differentiation protocols and enhance the feasibility of using patient-specific iPSCs and autologous PRP for future beta cells replacement therapies for T1DM. J. Cell. Physiol. 232: 2878-2886, 2017. © 2016 Wiley Periodicals, Inc.

The studies have been done on patient-specific human adipose-derived from mesenchymal stem cells (hADSCs) like a series of autologous growth factors and nanofibrous scaffolds (3D culture) will probably have many benefits for regenerative medicine in type 1 diabetes mellitus (TIDM) patients in the future. For this purpose, we established a polyvinyl alcohol (PVA) scaffold and a differentiation protocol by adding platelet-rich plasma (PRP) that induces the hADSCs into insulin-producing cells (IPCs). The characteristics of the derived IPCs in 3D culture were compared with conventional culture (2D) groups evaluated at the mRNA and protein levels. The viability of induced pancreatic cells was 14 days. The in vitro studies showed that the treatment of hADSCs in the 3D culture resulted in differentiated cells with strong characteristics of IPCs including pancreatic-like cells, the expression of the islet-associated genes at the mRNA and protein levels in comparison of 2D culture group. Furthermore, the immunoassay tests showed that these differentiated cells in these two groups are functional and secreted C-peptide and insulin in a glucose stimulation challenge. The results of our study for the first time demonstrated that the PVA nanofibrous scaffolds along with the optimized differentiation protocol with PRP can enhance the differentiation of IPCs from hADSCs. In conclusion, this study provides a new approach to the future pancreatic tissue engineering and beta cell replacement therapies for T1DM.

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Breast cancer is one of the most prevalent cancers in women. Triple‐negative breast cancer consists 15% to 20% of breast cancer cases and has a poor prognosis. Cancerous transformation has several causes one of which is dysregulation of microRNAs (miRNAs) expression. Exosomes can transfer miRNAs to neighboring and distant cells. Thus, exosomal miRNAs can transfer cancerous phenotype to distant cells. We used gene expression omnibus (GEO) datasets and miRNA target prediction tools to find overexpressed miRNA in breast cancer cells and their target genes, respectively. Exosomes were extracted from MDA‐MB‐231 and MCF‐7 cells and characterized. Overexpression of the miRNAs of MDA‐MB‐231 cells and their exosomes were analyzed using quantitative Real‐time PCR. The target genes expression was also evaluated in the cell lines. Luciferase assay was performed to confirm the miRNAs: mRNAs interactions. Finally, MCF‐7 cells were treated with MDA‐MB‐231 cells’ exosomes. The target genes expression was evaluated in the recipient cells. GSE60714 results indicated that miR‐9 and miR‐155 were among the overexpressed miRNAs in highly metastatic triple negative breast cancer cells and their exosomes. Bioinformatic studies showed that these two miRNAs target PTEN and DUSP14 tumor suppressor genes. Quantitative Real‐time PCR confirmed the overexpression of the miRNAs and downregulation of their targets. Luciferase assay confirmed that the miRNAs target PTEN and DUSP14. Treatment of MCF‐7 cells with MDA‐MB‐231 cells’ exosomes resulted in target genes downregulation in MCF‐7 cells. We found that miR‐9 and miR‐155 were enriched in metastatic breast cancer exosomes. Therefore, exosomal miRNAs can transfer from cancer cells to other cells and can suppress their target genes in the recipient cells.