Suppression of Proliferation of MCF-7 Human Breast Cancer Cell Line by △Np73 RNA Interfering Plasmids

DUAN Si; ZHANG Yufeng; WANG Shuang; ZHU Chenjie; WANG Yang; ZHANG Pei

Abstract：Objective To suppress the expression of △Np73 by RNA interference, observing its effect on the proliferation of hu-man breast cancer cell line MCF-7. Methods △Np73 expression plasmids were constructed and transfected into human breast canc-er cell line MCF-7 by liposome method. Transfection efficiency was calculated by counting green fluorescent protein expressing cells under fluorescence microscope. Cell growth inhibition rate was detected by MTT assay. △Np73 and TAp73 mRNA expression was measured by real-time PCR. After pcDNA3-HA/ DNp73α expression plasmids were co-transfected with △Np73 plasmids, Western Blot test was used to detect △Np73 and TAp73 expression level. Results △Np73 plasmids were successfully constructed and the transfection rate reached 62% . Cell proliferative activity of MCF-7 was significantly decreased by the transfection of △Np73 siRNA plasmid compared with negative control group. △Np73 siRNA plasmid transfection effectively inhibited endogeneous △Np73 mRNA expression and exogenous △Np73 protein expression, showing no obvious inhibitory effects on TAp73 mRNA protein expression. Con-clusion △Np73 siRNA expression plasmids can significantly down regulate △Np73 mRNA and protein expression in MCF-7 cells, and inhibit cell growth and proliferation, indicating that targeting silence of △Np73 can be a promising strategy for treating breast canc-er in the future.