外源性信号通路JAK/STAT在ALA-光动力诱导人SCC细胞凋亡中的作用

Effects of exogenous signal transduction pathway JAK/STAT on apoptosis of human SCC cells induced by ALA-PDT

目的:明确外源性凋亡机制(JAK/STAT信号通路)在5-ALA-PDT诱导人鳞状细胞癌细胞(SCC)凋亡中的作用。方法:体外培养鳞状细胞癌细胞系A431和COLO-16,分为空白对照组、转染阴性对照组、光动力组、转染阴性+光动力组、STAT3高表达载体组、STAT3-siRNA组、STAT3高表达载体+光动力组,STAT3-siRNA组+光动力组。CCK-8,流式细胞术(FCM)法分别检测各组细胞的存活率和凋亡率,qRT-PCR和Western Blot检测STAT3及其下游基因Bax和Bcl-2的mRNA和蛋白水平。结果:5-ALA-PDT组A431和COLO-16凋亡率为24%和22%高于STAT3高表达载体+光动力组(11%和10.5%),低于STAT3-siRNA+光动力组(36%和39%);5-ALA-PDT组STAT3和Bcl-2 mRNA水平和蛋白水平低于高表达载体+光动力组,高于STAT3-siRNA组。5-ALA-PDT组Bax mRNA和蛋白的水平高于高表达载体+光动力组,低于STAT3-siRNA组。结论:外源性凋亡通路JAK-STAT3可能参与5-ALA-PDT诱导的上皮鳞癌细胞的凋亡过程。

Objective:To determine the effect of exogenous signal transduction pathway JAK/STAT on apoptosis of human SCC cells induced by 5-ALA-PDT.Methods:Squamous cell carcinoma cell line A431 and COLO-16 cells were cultured in vitro,and then were divided into blank control group,negative control group,PDT group,negative control+PDT group,STAT3 high expression vector group,STAT3-siRNA group,STAT3 high expression vector+PDT group and STAT3-siRNA+PDT group.The survival rate and apoptosis rate were detected by CCK-8 method and flow cytometry method(FCM).The expression level of mRNA and protein of STAT3 and the downstream gene of Bax and Bcl-2 were detected by qRT-PCR and Western Blot.Results:The apoptosis rate of A431 and COLO-16 cells were 24%and 22%in PDT group,which were higher than in the STAT3 high expression vector+PDT group(11%and 10.5%),but lower than those in the STAT3-siRNA+PDT group(36%and 39%).The level of STAT3 and Bcl-2 mRNA and protein in the PDT group were higher than those in the STAT3 high expression vector+PDT group,but lower than those in the STAT3-siRNA+PDT group.The level of BCL-2mRNA and protein in PDT group was lower than that in the STAT3 high expression vector+PDT group,but higher than that in the STAT3-siRNA+PDT group.Conclusion:Exogenous apoptotic pathway JAK-STAT3 may involved in the apoptosis of squamous cancer cells induced by 5-ALA-PDT.