miR-195 inhibits cell proliferation via targeting AEG-1 in hepatocellular carcinoma

Emerging evidence has indicated that microRNAs (miRNAs) are frequently dysregulated and are fundamental in the pathogenesis of hepatocellular carcinoma (HCC). However, the roles of miR-195 in HCC have not been well elucidated. In the present study, the expression of miR-195 was determined to be markedly downregulated in HCC tissues and cell lines, as compared with normal liver cells. Restoration of miR-195 expression resulted in significant inhibition of the proliferation and tumorigenicity of HCC cells in vitro and in vivo. Gene expression data and luciferase reporter assays revealed that miR-195 is able to directly inhibit the expression of astrocyte elevated gene 1 (AEG-1) through interaction with its 3' untranslated region. Consistently, an inverse correlation between miR-195 and AEG-1 expression was observed in HCC tissues. Furthermore, the overexpression of AEG-1 was able to partially attenuate the miR-195-induced inhibition of cell growth and promotion of apoptosis. Taken together, these findings indicate that miR-195 functions as a tumor suppressor by inhibiting AEG-1. This pathway may provide new insights into the potential molecular mechanisms of HCC.