Enhanced inhibitory effect and mechanisms of adenovirus-mediated hepatocellular carcinoma supressor gene 1 combined with 5-FU on growth of LoVo cells / 中华消化杂志

ABSTRACT

Objective To observe the enhanced inhibitory effect of adenovirus (Ad)-mediated HCCS1 combined with 5-FU on the growth of LoVo cells, and to explore the molecular mechanisms.Methods RT-PCR and Western blot were used to detect the expression of HCCS1 in LoVo cells infected with Ad HCCS1. CCK-8 assay was applied to observe different inhibitory effects of different treatments on growth of LoVo cells. The apoptotic rates were detected by using flow cytometry. The apoptotic proteins were detected by using Western blot. Results ① The recombinant adenovirus, Ad HCCS1, could trigger the expression of HCCS1 in LoVo cell. ② In comparison with controls (92.23%±3.77%), the cell viability rate of LoVo was only (11.23±4.61 )% on 96 h after the combination treatment of 5-FU and Ad-HCCS1 (P<0. 01). ③ The apoptotic rate was (27.57±1.78)% on 72 h after the combination treatment, which was higher than that in 5-FU treated cells (8.64±0.94)%, Ad-HCCS1 treated cells (13.19±1.32)% and 5-FU Ad treated cells (12.16±1.28)%, (P<0. 01). ④ Cathepsin D was only detected in Ad HCCS1-infected cells. When treated with 5-FU, the procaspase-8 was decreased and the cleaved Bid was increased in cytosol. The lowest level of Bax and the highest level of cytoso C and cleaved caspase-3 were detected in cytosols of 5-FU+Ad HCCS1 treated cells. Conclusion The inhibitory and proapoptotic effects are significantly enhanced in LoVo cells when treated with Ad-HCCS1+5-FU. The key protein of the cross-talk is Bax and these data provided a new strategy to treat colorectal carcinomas.