Inhibition of autophagy potentiates the proliferation inhibition activity of microRNA‑7 in human hepatocellular carcinoma cells
- Yanna Wang
- Qiaoling Wang
- Jiqing Song
Published online on: July 15, 2017
MicroRNAs (miRNAs/miRs) are important molecules that are able to regulate multiple cellular processes in cancer cells. miR‑7 has been previously identified as a tumor suppressive miRNA in several types of cancer. The aim of the present study was to investigate whether miR‑7 is able to regulate autophagy in hepatocellular carcinoma (HCC) cells. It was identified that miR‑7 was significantly downregulated in tumor tissues compared with adjacent normal tissues. Overexpression of miR‑7 inhibited cell proliferative activity, which was partially reversed by miR‑7 inhibitor. In addition, overexpression of miR‑7 significantly induced an increasen in autophagic activity, and luciferase activity assay and western blot analysis identified that mammalian target of rapamycin (mTOR) was a direct target of miR‑7. In addition, inhibition of autophagy by 3‑methyladenine resulted in a marked enhancement of the proliferation inhibition effect of miR‑7. In conclusion, miR‑7 was identified to induce proliferation inhibition and autophagy in HCC cells by targeting mTOR, and inhibition of autophagy may be utilized to enhance the antitumor activity of miR‑7.