miR-145 modulates lncRNA-ROR and Sox2 expression to maintain human amniotic epithelial stem cell pluripotency and β islet-like cell differentiation efficiency

• miR-145 silences lncRNA-ROR and Sox2 expression via binding of specific sites on them.
• Inhibiting lncRNA-ROR weakens the efficiency of HuAECs differentiated into β islet cells.
• lncRNA-ROR effectively maintains Sox2 expression via competitive binding to miR-145.

In this study, we observed a great reduction in the expression of the endogenous long noncoding RNA ROR (lncRNA-ROR) and the stem cell transcription factor Sox2, in contrast to a marked increase in miR-145 expression, during the course of in vitro induced differentiation of human amniotic epithelial stem cells (HuAECs). Bioinformatics analysis and the luciferase reporter assay revealed binding of miR-145 to specific sites in lncRNA-ROR and Sox2, silencing their expression. Overexpression of a lncRNA-ROR-specific siRNA effectively downregulated the expression levels of Sox2 and other stem cell markers in HuAECs while weakening the efficiency of HuAEC differentiation into β islet-like cells. Moreover, the in vitro response of HuAEC-derived β islet-like cells to extracellular stimuli and C-peptide release by these cells were markedly weakened in the siRNA-ROR transfection group. Furthermore, the in vivo expression of β islet-like cell biomarkers was substantially reduced in HuAECs in the siRNA-ROR transfection group, and their in vivo β islet-like cell differentiation and insulin release capacities were reduced in a streptozocin-induced diabetic rat model. The experimental results indicate that lncRNA-ROR effectively maintains Sox2 gene expression through competitive binding to miR-145, achieving pluripotency maintenance in HuAECs and regulation of their directed β islet-like cell differentiation efficiency.