头颈部鳞状细胞癌细胞热疗后HSP70/HSP90的表达规律及其抑制对热疗疗效的影响

目的探讨口腔鳞状细胞癌（简称鳞癌）CA9-22细胞系热疗后HSP70/HSP90的表达规律及抑制HSP70/HSP90表达对头颈部鳞癌热疗的影响。方法①对体外培养的口腔鳞癌CA9-22细胞,恒温水浴42℃热休克2h,荧光定量PCR检测HSP70/HSP90的基因表达规律,采用Western-blot检测蛋白表达量的变化;②流式细胞术检测热休克前、后2、4、6、8、12、24h细胞的凋亡情况,观察在热疗前应用槲皮素、格尔德霉素及联合对HSP70/HSP90的抑制后对热疗的增敏效果。结果①42℃热疗后CA9-22细胞HSP70/HSP90表达在基因及蛋白水平上均有明显升高,4h达到高峰,8h后开始回落,24h接近正常;②热疗前使用槲皮素及格尔德霉素处理,凋亡细胞比例明显增加,联合处理组增加更为明显。结论 HSP70/HSP90在CA9-22细胞内的表达在热疗后迅速升高,在热疗前联合抑制HSP70/HSP90的活性,可以有效增加热疗敏感性。

HSP70/HSP90 Expression in CA9-22 after thermotherapy and the effect of inhibition of HSP70/ HSP90 expression on the efficacy of thermotherapy

OBJECTIVE To investigate the changes of HSP70/HSP90 expression in CA9-22 after thermotherapy and to explore the effects of inhibition of HSP70/HSP90 expression on the efficacy of thermotherapy. METHODS CA9-22 cells were incubated at 42℃ for 2 hours. The changes of mRNA and protein level of HSP70/ HSP90 were detected by real-time PCR and western-blot. CA9-22 cells were treated with quercetin,geldanamycin or quercetin plus geldanamycin before heat treatment respectively. Flow cytometry assay was used to determine the apoptosis of CA9-22 cells before thermotherapy and at 2h,4h,6h, 8h,12h and 24h after thermotherapy. RESULTS HSP70/HSP90 expression was up-regulated at 2h,reached to peak at 4h,descended at 8h and returned to the normal level at 24h after thermotherapy. Combined pretreatment with quercetin and geldanamycin can significantly induce CA9-22 apoptosis compared with pretreatment with quercetin or geldanamycin alone. CONCLUSION HSP70/HSP90 expression in CA9-22 is promptly up-regulated after thermotherapy. Inhibition of expression and activity of HSP70/HSP90 before thermotherapy can increase sensitivity of the tumor cell to heat treatment.