MicroRNA-127 post-transcriptionally downregulates Sept7 and suppresses cell growth in hepatocellular carcinoma cells.

BACKGROUND/AIMS Hepatocellular carcinoma is one of the most common cancers worldwide. It has been suggested that microRNAs, a class of small regulatory RNAs, are associated with tumorigenesis by targeting the mRNAs of hundreds of genes that modulate a variety of biological processes, including cellular differentiation, apoptosis, metabolism, and proliferation. METHODS/RESULTS we analyzed the expression levels of mir-127 in 33 HCC and non-cancerous tissues using qRT-PCR. MiR-127 is downregulated in 69.7% of HCC tissues compared with adjacent normal tissues, but its expression level is not correlated with the TNM stage, AFP level, or age. In vitro, miR-127 can arrest Huh7 at the G2/M phase and inhibit Huh7 cell proliferation. In an in vivo xenograft model, the overexpression of miR-127 can inhibit Huh7 cell tumorigenicity. The luciferase reporter and western blot results confirm that miR-127 downregulates Sept7 expression by targeting its 3'UTR. Furthermore, the knockdown of Sept7 has the same effect on cell proliferation as the overexpression of miR-127 in Huh7 cells. CONCLUSION miR-127 plays a tumor-suppressor role and can serve as a potential diagnostic biomarker for HCC.