Effect of bevacizumab on apoptosis of drug-resistant nasopharyngeal carcinoma cells / 解放军医学杂志

ABSTRACT

Objective To investigate the effect of bevacizumab on apoptosis of drug resistant nasopharyngeal carcinoma(NPC) cells in vitro.Methods The human nasopharyngeal carcinoma(NPC) cell line CNE2 and its cisplatin-resistant CNE2/DDP cells were treated with bevacizumab and DDP in various concentrations.The lethal effects of the both drugs and the apoptosis rates on CNE2/DDP cells were then measured separately with MTT assay and flow cytometry,the mRNA expressions of Bcl-2 and Bax in CNE2,CNE2/DDP and CNE2/DDP/Bev cells were detected with semi-quantitative RT-PCR.Results The killing rate in 10?g/ml bevacizumab group was similar to that of blank group(0.0?4.1% vs.5.2?4.3%,P=0.180),while the rates of combination of 10?g/ml bevacizumab and DDP(0.1?g/ml and 0.2?g/ml,separately) were higher than that of using DDP only(42.3?6.5% vs.34.4?5.4%,P=0.041;62.6?5.5% vs.50.0?5.9%,P=0.009).The apoptotic rate of CNE2/DDP,which was caused by combining 0.1?g/ml DDP and 10?g/ml bevacizumab,was much higher than what was produced by DDP alone(87.29?3.38% vs.50.58?8.83%,P=0.049).By means of semi-quantitative RT-PCR assay,the expressions of Bcl-2 mRNA in CNE2,CNE2/DDP and CNE2/DDP/Bev cells were 0.613,0.952 and 0.135,respectively.Meanwhile,the expressions of Bax mRNA were 0.665,0.387 and 1.751,separately.Conclusion Bevacizumab can greatly increase the drug sensitivity of CNE2/DDP cells to DDP;apoptosis is inhibited in MDR cells,but it can be promoted by bevacizumab.