BFGF Induced Human Gastric Cancer Cell Line MGC-803 Rensistance To Bevacizumab By Activating NF-kappaB

Objective:To explore whether the b FGF induce human gastric cancer cells MGC-803 rensistance to Bevaeizumab and the mechanism.Methods:(1) Three groups were set, control group, drug group, and experimental group. The drug group was treated with Bevacizumab(22ng/ml) for 12 hours. The experimental group was pretreated with b FGF(30ng/ml) for 12 hours, and then treated with Bevacizumab(22ng/ml) for 12 hours. CCK-8 method was used to observe the effect of b FGF on cells proliferation.(2) To investigate mechanism of drug resistance of human gastric cancer cells MGC-803 to Bevacizumab. Cells were divided into three groups randomly. The experimental group was pretreated with b FGF for 12 hours, and then treated with Bevacizumab(30ng/ml) for 12 hours. The negative group was pretreated with b FGF(30ng/ml) for 12 hours, and then treated with the selective inhibitor PDTC(10?mol/L) of NF-kappaB for 30 minutes and Bevacizumab(22ng/ml) for 12 hours. The positive group was pretreated with NF-kappaB agonist TNF-?(30ng/ml), and treated with Bevacizumab(22ng/ml) for 12 hours. Western Blot was used to detect expression of nuclear NF-kappaB protein and cytoplasmic NF-kappaB protein among all groups. Immunocytochemistry was used to survey nuclear translocation(activation) of NF-kappaB.Results:(1) After treated with Bevacizumab for 12 huors, cell relative viability weakened, Bevacizumab can inhibit proliferation of MGC-803. However, the cell relative viability was obviously increased after pretreated with b FGF for 12 hours, and the sensibility to Bevacizumab descended.(2) Compared to cells only treated with b FGF for 12 hours, the cell relative viability was distinctly declined after treated with the inhibitor of NF-kappaB PDTC for 30 minutes. This revealed PDTC could reverse drug resistance of Bevacizumab induced by b FGF. Compared to cells simply treated with Bevacizumab for 12 hours, the cell relative viability was obviously increased after pretreated with the agonist of NF-kappaB TNF-?for 30 minutes, and the sensibility to Bevacizumab descended.(3) Nuclear NF-kappaB protein up-regulated after cells resp ectively pretreated with b FGF for 12 hours and NF-kappaB agonist TNF-? for 30 minutes. Nevertheless, the cytoplasmic NF-kappaB p rotein had opposite expression, compared with cells only treated with Bevacizumab for 12 hours. It indicated b FGF could induce NF-ka ppa B activation(nuclear translocation) as well as TNF-?.Nuclear NF-kappaB protein down-regulated after cells treated with b FGF for 12 hours and NF-kappaB inhibitor PDTC for 30 minutes, however, th eir cytoplasmic NF-kappaB protein up-regulated.It may indicated P DTC could reverse NF-kappaB activation(nuclear translocation) ind uced by b FGF.(4) Nuclear mean optical density increased after cells respectively treated with b FGF for 12 hours and NF-kappaB agonist TNF- ? for 30 minutes, compared with cells only treated with Bevacizumab for 12 hours.It illustrated b FGF could induce NF-kappaB nuclear translocation(activation) as well as TNF-? again. Nuclear mean optical density declined dramatically after cells treated with b FGF for 12 hours and NF-kappaB inhibitor PDTC for 30 minutes, compared with cells were purely treated with b FGF for 12 hours. Thatpredicted PDTC could reverse NF-kappaB nuclear translocation(activation) induced by b FGF again.Conclusion : b FGF probably induces human gastric cells M-GC-803 resistant to Bevacizumab by activating NF-kappaB.