Effects of small interfering RNA silencing metastasis-associated in colon cancer-1 gene on the proliferation, migration and invasion of liver cancer cells

Abstract

Objective To investigate the effects of small interfering RNA (siRNA) silencing metastasis-associated in colon cancer-1 (MACC1) gene on the proliferation, migration and invasion of liver cancer cells, and the possible mechanism. Methods HepG2 cells were cultured. According to the different transfectants, the cells were divided into siRNA-MACC1 group, siRNA-NC group and blank control group. The cell proliferations in the different transfected groups were measured by methyl thiazol tetrazolium (MTT) assay. The cell apoptosis in the different transfected groups was examined by flow cytometry. The cell migration and invasion abilities in the different transfected groups were tested by Transwell methods. The expression levels of MACC1, hepatocyte growth factor (HGF) and c-Met genes in the different transfected groups were detected by real-time fluorescent quantitative polymerase chain reaction(FQ-PCR). The expression levels of MACC1, HGF, c-Met, MEK, phosphorylated MEK (p-MEK), extracellular signal-regulated kinase (ERK) and phosphorylated ERK (p-ERK) proteins in the different transfected groups were detected by Western blotting. Results (1) MTT results showed that absorptivity (A) values in the siRNA-MACC1 group at 24, 48, 72 and 96 h (0.27±0.05, 0.36±0.06, 0.46±0.05, 0.58±0.07) were lower than the siRNA-NC group (0.39±0.06, 0.47±0.05, 0.64±0.07, 0.75±0.08) and blank control group (0.41±0.05, 0.49±0.07, 0.62±0.06, 0.77±0.09), the differences were statistically significant (F=25.945, 32.286, 40.264, 38.165, P=0.000, 0.000, 0.000, 0.000). (2) Flow cytometry results showed that the apoptosis rate in the siRNA-MACC1 group was (13.52±2.61)%, which was significantly higher than the siRNA-NC group and blank control group [(4.94±1.84)%, (5.10±2.13)%, F=73.918, P=0.000]. (3) The number of migration cells and the number of invasive cells in the siRNA-MACC1 group (73.62±12.71, 59.23±11.53) were significantly lower than those in the siRNA-NC group and blank control group (98.53±14.22, 85.44±13.12 and 102.51±15.13, 87.62±14.24, F=11.149, 9.500, P=0.000, 0.000). (4) Compared with siRNA-NC group and blank control group, the relative expression levels of MACC1, HGF and c-Met mRNA in the siRNA-MACC1 group were significantly lower than the siRNA-NC group and blank control group (F=51.235, 137.507, 139.708, P=0.000, 0.000, 0.000). (5) Compared with the siRNA-NC group and blank control group, the relative expression levels of MACC1, HGF, c-Met, p-MEK and p-ERK proteins in the siRNA-MACC1 group were decreased (F=49.803, 33.564, 24.391, 228.400, 137.410, P=0.000, 0.000, 0.000, 0.000, 0.000), while the the relative expression levels of MEK and ERK proteins were increased (F=12.751, 23.829, P=0.000, 0.000). Conclusion Specific inhibition of MACC1 gene expression in HepG2 cells could effectively inhibit cell proliferation, decrease cell migration and invasion, and induce cell apoptosis. The mechanism might be related to HGF/Met and MEK/ERK signaling pathways. Key words: Liver cancer; Metastasis-associated in colon cancer-1; Small interfering; Biological characteristics