Research Of Drug Resistance Reversal On HepG₂ Liver Cancer Cell Lines By Small Interference RNA Of Transforming Growth Factor β1

Objective :To explore the effect of drug resistance reversal on HepG2 liver cancer cell lines by the expression of TGF-β1 siRNA.Methods : HepG2 cells were cultivated with cisplatin of 1/5 IC50 for 3 days,5 days and 7 days, then analyze it's cell cycle with flow cytometer. One 23 bp siRNA which specifically targeted TGF-β1 gene was designed on base of the coding regions. Transfection of siRNA into HepG2/CDDP cells was performed using liposome transfection reagents , the HepG2/CDDP cells were cultivated for 3 days,5 days and 7 days . The expression level of TGF-β1 mRNA was determined using reverse transcription polymerase chain reaction (RT-PCR). Drug sensitivity of HepG2/CDDP cells to cisplatin was analyzed by MTT assay. Immunohistochemical assay was performed to assess the experssion of TGF-β1 and P-glycoprotein (P-gp).Results : The kinetic drug fast model of HepG2/CDDP was established ,it's cell cycle was arrested at G0/G1 phase by flow cytometer . The expression level of TGF-β1 mRNA,TGF-β1 protein and P-gp in HepG2/CDDP cells were all reduced by the transfection of TGF-β1 gene specific siRNAs, and the drug sensitivity to cisplatin was enhanced after the transfection . The expression level of P-gp in HepG2/CDDP cells which were cultivated with cisplatin for respectively 3 days and 5 days and its'drug sensitivity to cisplatin have no evidently changed after the transfection of TGF-β1 gene specific siRNAs.Conclusions : The cell cycle of HepG2/CDDP kinetic drug fast model was blocked at G0/G1 phase;The expression of TGF-β1and P-gp could partly interrupted after the transfection of TGF-β1 siRNA,and the drug sensitivity of HepG2 cells to cisplatin was also enhanced after the transfection; The drug resistance of HepG2 cells to cisplatin could be partly reversed by TGF-β1 siRNA.