MicroRNA-21 inhibits ovarian granulosa cell proliferation by targeting SNHG7 in premature ovarian failure with polycystic ovary syndrome.

microRNA (miRs or miRNAs) is a type of non-coding RNA which plays the role of a regulator in gene expression. A number of miRNAs has been found by the researchers for its critical role in the pathogenesis of polycystic ovary syndrome (PCOS). But there is a no clear information available about the biological role played by miR-21 in PCOS prognosis. So, the aim of the current study is to determine the role played by miR-21 in the progression of PCOS. In order to achieve this aim, the researcher examined miR-21 expression levels in ovarian tissue samples collected from PCOS patients as well as their KGN cells (human granulosa-like tumor cell line). The study results inferred downregulation in the expression levels of miR-21 in ovarian tissues of PCOS patients and KGN cells, when compared with unaffected ovarian tissues and IOSE80 (human ovarian surface epithelial cell line). With the overexpression of miR-21, the proliferation of KGN cells was prevented and apoptosis was induced among these cells. The authors used StarBase analysis for predicting the direct binding target of miR-21. As per the assay results attained from luciferase reporter assay and western blot analysis, it was found that SNHG7 acted as a target gene for miR-21 while the latter downregulated the former. To conclude, the current study revealed the contribution of miR-21/SNHG7 axis in the regulation of Granulosa Cell (GC) proliferation and apoptosis. It further suggested a new molecular mechanism for GC dysregulation while the finding presents a new promising target for PCOS treatment procedure.