[Down regulation of multidrug resistance-associated protein 4 expression by RNA interference enhances radiosensitivity of colorectal carcinoma cell lines in vitro].

摘要: Objective To investigate the effect of multidrug resistance-associated protein 4 (MRP4) expression on radiosensitivity colorectal carcinoma cell lines in vitro.Methods The vector shRNA for RNA interference was constructed and then transfected into HCT116 line to steadily down-regulate MRP4.HCT116 cells were divided 3 groups including CON group (non-transfected),NC (negative control virus added),and KD (RNAi target added transfection).To test effectiveness interference,real-time polymerase chain reaction Western blot used measure pattern MRP4 at both mRNA levels,respectively.For examination radiosensitivity,flow cytometry calculate rate apoptotic 24 h after Gy radiation.Proliferation measured via MTT assay different time points.Results ShRNA plasmid successfully constructed.Transfection this caused steady silencing (HCT116-KD).MRP4 significantly down-regulated following (P＜0.05).Twenty-four hours radiation,the apoptosis (71.7±0.8)％,significantly higher than that [ (56.1±0.9)％]and NC [(59.8±0.8)％ ] (P＜0.05).Fourty-eight 72 proliferation inhibited compared (P＜0.05).Conclusions Expression is closely related radiotolerance carcinoma.Downregulation by enhances vitro.MRP4 may be an effective molecular marker predicting carcinoma. Key words: Colorectal carcinoma;  Multidrug 4;  ;  Radiosensitivity