miR-328-3p overexpression attenuates the malignant proliferation and invasion of liver cancer via targeting Endoplasmic Reticulum Metallo Protease 1 to inhibit AKT phosphorylation

Background: Liver cancer is one of the most common cancers worldwide. microRNAs (miRNAs) have been recognized as minimally invasive prognostic markers for distinct types of cancer. This study evaluates the mitigation role of miR-328-3p on liver cancer in vitro and in vivo.

Methods: Liver cancer cell line Huh-7 and HepG2 were used for in vitro experiments. Compared with the control group, miR-328-3p overexpression inhibited the proliferation, invasion, and promoted apoptosis of Huh-7 cells. miR-328-3p and endoplasmic reticulum metalloprotease 1 (ERMP1) had an excellent targeting relationship. Compared with the pcDNA-ERMP1 transfection group, the ratios of p-PI3K/PI3K, p-AKT/AKT, and p-mTOR/mTOR in miR-328-3p mimic and pcDNA-ERMP1 co-transfection group were significantly decreased. Animal models were set up using four-week-old immunodeficient BABL/c female nude mice. Huh-7 cells transfected with lentivirus holding miR-328-3p or empty vector were injected into the right dorsal side of BABL/c nude mice, respectively. Tumor volume was measured every five days. After one month, animals were sacrificed, xenograft tumors were dissected and weighed for RT-PCR and immunohistochemical assays.

Results: Compared with control group, miR-328-3p overexpression significantly inhibited tumor weight (0.46±0.07 vs. 0.11±0.05 g, P<0.05) and tumor volume (1876±321 vs. 543±168 mm³, P<0.05) after thirty days. miR-328-3p overexpression significantly downregulated the percentage of Ki67 positive cells, N-cadherin positive cells and vimentin positive cells.

Conclusions: These findings suggested that miR-328-3p could be a new treatment or a novel marker for liver cancer prognosis.

Keywords: Huh-7 cells; Liver cancer; apoptosis; invasion; miR-328-3p.