Nowadays, tissue engineering by using stem cells in combination with scaffolds and bioactive molecules has made significant contributions to the regeneration of damaged bone tissues. Since the usage of bioactive molecules including, growth factors to induce differentiation is safety limited in clinical applications, and it has also been previously observed that extremely low frequency pulsed electromagnetic fields (PEMF) can be effective in the enhancement of proliferation rate and osteogenic differentiation of stem cells, the aim of this study was investigating the osteoinductive potential of PEMF in combination with Poly(caprolactone) (PCL) nanofibrous scaffold. To achieve this aim, Adipose-derived mesenchymal stem cells (ADSCs) isolated and characterized and then osteogenic differentiation of them was investigated after culturing on the surface of PCL scaffold under treatments of PEMF, PEMF plus osteogenic medium (OM) and OM. Analysis of common osteogenic markers such as Alizarin red staining, ALP activity, calcium content and four important bone-related genes in days of 7, 14, and 21 confirmed that the effects of PEMF on the osteogenic differentiation of ADSCs are very similar to the effects of osteogenic medium. Thus, regarding the immunological concerns about the application of bioactive molecules for tissue engineering, PEMF could be a good alternative for osteogenic medium. Although, results were showed a synergetic effect for simultaneous application of PEMF and PCL scaffold in the osteogenesis process of ADSCs. Taking together, ADSCs-seeded PCL nanofibrous scaffold in combination with PEMF could be a great option for use in bone tissue engineering applications.

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Tissue engineering is fast becoming a key approach in bone medicine studies. Designing the ideally desirable combination of stem cells and scaffolds are at the hurt of efforts for producing implantable bone substitutes. Clinical application of stem cells could be associated with serious limitations, and engineering scaffolds that are able to imitate the important features of extracellular matrix is a major area of challenges within the field. In this study, electrospun scaffolds of polyvinylidene fluoride (PVDF), PVDF-graphene oxide (GO), PVDF-polyvinyl alcohol (PVA) and PVDF-PVA-GO were fabricated to study the osteogenic differentiation potential of human induced pluripotent stem cells (iPSCs) while cultured on fabricated scaffolds. Scanning electron microscopy study, viability assay, relative gene expression analysis, immunocytochemistry, alkaline phosphates activity, and calcium content assays confirmed that the osteogenesis rate of hiPSCs cultured on PVDF-PVA-Go is significantly higher than other scaffolds. Here, we showed that the biocompatible, nontoxic, flexible, piezoelectric, highly porous and interconnected three-dimensional structure of electrospun PVDF-PVA-Go scaffold in combination with hiPSCs (as the stem cells with significant advantageous in comparison to other types) makes them a highly promising scaffold-stem cell system for bone remodeling medicine. There was no evidence for the superiority of PVDF-GO or PVDF-PVA scaffold for osteogenesis, compared to each other; however both of them showed better potentials as to PVDF scaffold.

Tumor cell invasion and metastasis are the definitive cause of mortality in breast cancer (BC). Hypoxia and pro‐inflammatory cytokines upregulate the CD73 gene in the tumor microenvironment. Subsequently, CD73 triggers molecular and cellular signaling pathways by both enzymatic and nonenzymatic pathways, which finally leads to breast tumor progression and development. In this paper, we summarize current advances in the understanding of CD73‐driven mechanisms that promote BC development and mortality. Furthermore, we evaluate the therapeutic potential of CD73 targeting in BC.

Understanding gene regulation mechanisms has been a serious challenge in biology. As a novel mechanism, small non-coding RNAs are an alternative means of gene regulation in a specific and efficient manner. There are growing reports on regulatory roles of these RNAs including transcriptional gene silencing/activation and post-transcriptional gene silencing events. Also, there are several known small non-coding RNAs which all work through RNA interference pathway. Interestingly, these small RNAs are secreted from cells toward targeted cells presenting new communication approach in cell-cell or cell-organ signal transduction. In fact, understanding cellular and molecular basis of these pathways will strongly improve developing targeted therapies and potent and specific regulatory tools. This study will review some of the most recent findings in this subject and will introduce a super-pathway RNA interference-based small RNA silencing network.