盐霉素对鼻咽癌细胞放疗敏感性的影响

Effects of salinomycin on the radiotherapy sensitivity of nasopharyngeal carcinoma cells

目的研究盐霉素对鼻咽癌细胞放疗敏感性的影响及其机制。方法鼻咽癌CNE2细胞株分为盐霉素组(4μmol·L-1盐霉素),放疗组(6 Gy辐照),联合组(4μmol·L-1盐霉素+6 Gy辐照),对照组细胞常规培养。用溴化四唑蓝比色法(MTT)及AO/EB凋亡试剂盒分别检测细胞增殖和凋亡情况,用蛋白质免疫印迹法检测细胞中半胱氨酸天冬氨酸特异性蛋白酶-3(caspase-3)和核因子-κB(NF-κB)蛋白表达情况,用克隆形成实验检测鼻咽癌CNE2细胞存活分数(SF2)。结果盐霉素组、放疗组、联合组48 h增殖抑制率分别为(20.58±2.06)%,(30.58±2.46)%,(39.56±2.30)%;凋亡率分别为(23.69±2.45)%,(25.46±2.68)%,(45.26±3.15)%;caspase-3蛋白相对表达量分别为0.65±0.13,0.89±0.07,1.15±0.26;NF-κB蛋白相对表达量分别为0.98±0.04,0.76±0.10,0.13±0.02,联合组分别与盐霉素组和放疗组比较,差异均有统计学意义(均P <0.05)。放疗组SF2为52%,联合组SF2为34%,差异有统计学意义(P <0.01)。结论盐霉素可抑制鼻咽癌细胞增殖,同时可增加鼻咽癌细胞对放疗的敏感性,主要是通过上调caspase-3表达及抑制NF-κB活化促进细胞凋亡来实现。

Objective To investigate the effect of salinomycin on the radiotherapysensitivity,proliferation and apoptosis of nasopharyngeal carcinoma cells.Methods CNE2 cell lines of nasopharyngeal carcinoma were divided into salinomycin group(4 mol·L-1 salinomycin),radiotherapy group(6 Gy radiation),combination group(4 mol·L-1 salinomycin+6 Gy radiation),and control group was subjected to routine treatment.Cell proliferation and apoptosis were detected by MTT and AO/EB apoptotic kit,respectively.The expression of Caspase-3 and nuclear factor-kappa B(NF-κB)in nasopharyngeal carcinoma CNE2 cells was detected by Western blot.The survival fraction(SF2)of CNE2 cells was detected by clone formation assay.Results In salinomycin group,radiotherapy group and combination group,the inhibition rates were(20.58±2.06)%,(30.58±2.46)%,(39.56±2.30)%,respectively;the apoptosis rates were(23.69±2.45)%,(25.46±2.68)%,(45.26±3.15)%,respectively;the relative expressions of caspase-3 protein were 0.65±0.13,0.89±0.07,1.15±0.26,respectively;the relative expressions of NF-κB protein were 0.98±0.04,0.76±0.10,0.13±0.02,respectively.There were statistically significance between the combination group and the salinomycin group/radiotherapy group(P<0.05).SF2 was 52%in radiotherapy group and 34%in combination group,and statistically significant difference was found between the two groups(P<0.01).Conclusion Salinomycin can inhibit the proliferation of nasopharyngeal carcinoma cells,and can increase the radiotherapy sensitivity of nasopharyngeal carcinoma cells,mainly by upregulation of caspase-3 expression and inhibition of NF-κB activation to promote cell apoptosis.