siRNA-mediated downregulation of COX-2 gene expression alters the proliferation of hepatocellular carcinoma HepG2 cells.
Shijie Huaren Xiaohua Zazhi 2009;
17:2244-2250. [DOI:
10.11569/wcjd.v17.i22.2244]
[Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To explore the effects of siRNA-mediated downregulation of COX-2 gene expression on the proliferation of hepatocellular carcinoma HepG2 cells.
METHODS: HepG2 cells were divided into four groups: COX-2 siRNA intervention group, control siRNA intervention group, empty liposome group and blank control group. COX-2 siRNA was transfected into HepG2 cells by lipofection. Cell proliferation inhibition was measured at 24, 48 and 72 h after transfection by MTT (thiazolyl blue) assay. The changes in cell cycle distribution were detected at 24 h after transfection by flow cytometry. The expression levels of COX-2 and ERK1/2 mRNAs and proteins were detected at 24 h after transfection by semiquantitative RT-PCR and Western blot, respectively.
RESULTS: The proliferation inhibition rate achieved in the COX-2 siRNA intervention group was higher than those in the control siRNA intervention group and empty liposome group (67.08% vs 2.45% and 1.56%, both P < 0.01). The percentage of HepG2 cells arrested at G1 phase (DNA presynthetic phase) was increased in the COX-2 siRNA intervention group as compared to the control siRNA intervention group, empty liposome group and blank control group (72.80% vs 50.27%, 50.97% and 53.13%, all P < 0.05). Semiquantitative RT-PCR analysis showed that the expression levels of COX-2, ERK1 and ERK2 mRNAs in the COX-2 siRNA intervention group were significantly decreased as compared to the control siRNA intervention group, empty liposome group and blank control group (0.58 vs 0.83, 0.89 and 0.93; 0.32 vs 0.71, 0.64 and 0.76; 0.48 vs 0.65, 0.67 and 0.72; all P < 0.05). Similar results were obtained for protein expression as revealed by Western blot analysis.
CONCLUSION: siRNA can downregulate the expression of COX-2 gene in hepatocellular carcinoma HepG2 cells and inhibit their proliferation. COX-2 promotes the development of primary hepatic carcinoma perhaps through regulation of ERK1/2 pathway.
Collapse