MiR-93 Inhibits Trophoblast Cell Proliferation and Promotes Cell Apoptosis by Targeting BCL2L2 in Recurrent Spontaneous Abortion

Recurrent spontaneous abortion (RSA) is a common health problem that affects 1-5% of women in reproductive age. Plenty of studies have indicated that MicroRNAs (miRNAs) are involved in the occurrence of miscarriage. MiR-93 has a wide range of functions in mammalian tissues and plays an important role in many diseases especially for cancers. However, it remains unknown whether miR-93 is associated with human RSA. In this report, clinical samples revealed that miR-93 expression was significantly elevated in the villi tissues of RSA patients. Upregulation of miR-93 inhibited human trophoblast cells HTR-8/SVneo cell proliferation, migration, and invasiveness, but promoted cell Apoptosis in vitro. Conversely, the downregulation of miR-93 reversed these effects. Bcl-2 like protein 2 (BCL2L2), a potential target gene of miR-93, was inversely correlated with miR-93 expression in the villi of clinical samples. Furthermore, the luciferase reporter system demonstrated that miR-93 directly downregulated the expression of BCL2L2 by binding a specific sequence of its 3'-untranslated region (3'UTR). Collectively, these data strongly suggest that miR-93 regulates trophoblast cell proliferation, migration, invasive, and Apoptosis by targeting BCL2L2 expression and is involved in the pathogenesis of RSA.