The Tumor Suppressor MicroRNA-1 Exhibits Restricted Inhibition of Proliferation of Ovarian Cancer Cells

Background: MicroRNAs are able to control vital tumor biological processes, such as proliferation, tissue transformation and cell migration, as well as apoptosis. One of the micro RNAs, namely miR-1, has been classified as a tumor suppressor, however, preliminary data did not confirm this finding in ovarian cancer (OC) cells. This study examined the impact of miR-1 on OC cell growth. Materials and Methods: Recombinant miR-1 was overexpressed in human OC cell lines OVCAR-3, SK-OV-3, TOV-112D, and TOV-21G. Subsequently, cell growth was analyzed. Results: After transfection, 11- to 487-fold overexpression of miR-1 was detectable in the OC cells. However, no significant differences in proliferation compared to control cells were detected, neither in transiently nor in stably transfected cells. Conclusion: In numerous cancer entities miR-1 is defined as an antiproliferative tumor suppressor. Notably, the present study demonstrated a loss of growth-inhibitory functionality of miR-1 by so far unknown mechanisms, suggesting dysregulated miR-1 signaling or effector cascades in OC cells.