摘要
目的:探讨葡萄糖调节蛋白78(Glucose regulated protein78,GRP78)在不同胃癌细胞株中的表达和对化疗药物敏感性的关系,并探讨其初步机制。方法:用RT-PCR及Western blot法检测分化程度不同的胃癌细胞株MKN45、SGC7901和NCI-N87中GRP78的表达,并分别观察经Ca2+载体A23187和Ca2+螯合剂BAPTA-AM处理后的SGC7901中GRP78的表达,MTT法检测各组胃癌细胞株对多种化疗药物的敏感性。Western blot法检测SGC7901及分别经A23187和BAPTA-AM处理后细胞AKT/PKB蛋白表达水平,流式细胞仪检测细胞的凋亡率。结果:GRP78在3种胃癌细胞系中均有表达,在MKN45中为高表达,对化疗药物的敏感性最低;在NCI-N87中为低表达,但对化疗药物的敏感性最高。A23187组SGC7901细胞GRP78mRNA和蛋白及AKT/PKB蛋白的表达显著上调,对长春新碱(Vincristine,VCR)的敏感性降低;而在BAPTA-AM组则与之相反。结论:GRP78在不同分化的胃癌细胞株中表达水平不同,对化疗药物的敏感性亦不同。改变胃癌细胞GRP78的表达能影响其下游蛋白AKT/PKB的表达水平,从而影响胃癌细胞对化疗药物的敏感性。
Objective：To research the sensitivity of different gastric cancer cell lines to chemotherapeutic drugs and evaluate GRP78 expression in order to analyze the relation between them.Methods：The SGC7901 cells were treated by calcium ionophore A23187 and Ca2＋ chelator BAPTA-AM.The sensitivity of different gastric cancer cell lines to different chemotherapeutic drugs was detected by MTT assay.The expression of GRP78 was assessed by RT-PCR and Western blot.The expression of AKT/PKB in SGC7901,A23187-SGC7901 and BAPTA-AM-SGC7901 was analyzed by Western blot.Cell apoptosis was analyzed by flow cytometry in order to evaluate the therapeutic sensitivity to VCR.Results：GRP78 was expressed in all of the three gastric cancer cell lines.The expression of GRP78 at both protein and mRNA levels was the lowest in NCI-N87 cell,whose sensitivity to different chemotherapeutic drugs was the highest one.The expression of GRP78 at both protein and mRNA levels was the highest in MKN45 cell,whose sensitivity to different chemotherapeutic drugs was the lowest one.GRP78 was up-regulated and down-regulated by A23187 and BAPTA-AM respectively in gastric cancer cell line SGC7901.The sensitivity to VCR was the highest in BAPTA-AM-SGC7901,whose expression of AKT/PKB was the lowest one.On the contrary,the sensitivity to VCR was the lowest in A23187-SGC7901 whose expression of AKT/PKB was the highest.Conclusion：The expression of GRP78 in three gastric cancer cells is diverse,and the sensitivity of those cells to chemotherapeutic drugs is also different.Altering expression of GRP78 in gastric cancer cell can affect its downstream protein AKT/PKB expression levels,thereby affecting the sensitivity of gastric cancer cells to chemo-therapeutic drugs.
出处
《重庆医科大学学报》
CAS
CSCD
北大核心
2011年第1期46-50,共5页
Journal of Chongqing Medical University
关键词
胃癌
葡萄糖调节蛋白78
敏感性
gastric cancer
glucose-regulated protein78
sensitivity
