MiR-26a promotes ovarian cancer proliferation and tumorigenesis.

MicroRNAs (miRNAs) important for posttranscriptional gene expression are involved in the initiation and progression of human cancer. In this study, we reported that miR-26a was over-expressed in human EOC specimens and the expression level of extracellular miR-26a in plasma can distinguish patients from healthy controls in EOC. Ectopic expression of miR-26a in ovarian cancer (OC) cells increased cell proliferation and clonal formation. This growth promoting effect of OC cell growth was mediated by miR-26a inhibition of the posttranscription of ER-α. Furthermore, inhibition of miR-26a suppressed the tumor formation generated by injecting OC cells in nude mice. Our results suggest that aberrantly expressed miR-26a may contribute to OC development