Expression Of DLC-1 And Bcl-2 Gene: Effect Of IFN-a Combined With 5-FU On Human Hepatocellular Carcinoma Cell Line HepG-2

Objective To explore the effect of IFN-a combined with 5-Fluorouracil (5-FU) on cell cycle, apoptosis and the expression of DLC-1 and Bcl-2 gene of hepataocellular carcinoma cell line HepG-2,by observing the inhibition of proliferation,further explore the anti-tumor, pro-apoptotic mechanism of IFN-a combined 5-FU,and provide a theoretical basis of the clinical combination of cytokines and chemotherapeutic agents for treatment of cancer.Methods HepG-2 cells were cultured, and divided into 4 groups, namely control,IFN-a,5-FU, Combination groups.Cell proliferation was evaluated by MTT assay. Cell cycle, apoptosisratio were observed by Flow cytometric assay. mRNA expression of DLC-1 and Bcl-2 gene was measured by RT-PCR.Results MTT results showed that the inhibition effect of 5-FU plus IFN-a was significantly stronger than IFN-a and 5-FU alone.Compared with IFN-a group and 5-FU group,After 48h drug treatment,FCM prompted that the cell percent of IFN-a plus 5-FU group was decreased in S stage(16.27%);RT-PCR detected that the expression of DLC-1 of combination therapy group was higher than that of control,IFN-a,and 5-FU group, the expression of Bcl-2 of combination therapy group was lower than that of control,IFN-a,and 5-FU group.Conclusion The combination of IFN-a and 5-FU could suppress the proliferation and induce apoptosis of HepG-2 cells partly by up-regulation of DLC-1 and down-regulation of DLC-1 gene level. There was an obviously synergistic effect between IFN-a and 5-FU.The mechanism of synergistic effect on promoting apoptosis of hepataocellular carcinoma cells may be related to rising aspartate (caspase-3)-mediated apoptosis and inner signal pathway of apoptosis,there are some synergies between them.