热休克诱导人肝癌HepG2细胞HSP70和P-gp的表达及槲皮素对二者的抑制作用  

Expression of HSP70and P-glycoprot ein(P-gp)in Human Hepatocarcinoma HepG2Cells I nduced by Heat Shock and Inhibiting Effect of Quercetin on Them

作　　者：唐武兵 马佩球[2] 倪宏[2] 曾文铤[2] 朱科伦[2] 

机构地区：[1]佛山市南海人民医院肿瘤中心,广东佛山528200 [2]广州医学院第一附属医院肿瘤科,广东广州510120

出　　处：《癌症》2003年第9期954-958,共5页Chinese Journal of Cancer

基　　金：广东省中医药管理局科研基金(No.101045)

摘　　要：背景与目的:研究提示热休克蛋白70(heatshockprotein70,HSP70)可抑制细胞凋亡,降低肿瘤热疗、化疗的疗效,但其与细胞化疗耐受性的内在关系尚不甚明确;P-糖蛋白(P-glycoprotein,P-gp)是一种耐药蛋白,在肿瘤耐药中起重要作用。本研究拟通过热休克诱导人肝癌HepG2细胞表达HSP70和P-gp,并观察槲皮素(quercetin,Qu)对二者表达的抑制效应。方法:恒温水浴法,42℃热休克HepG2细胞90min,分别采用免疫组化、流式细胞术检测热休克前及热休克后2h、4h、8h、12h、24h时HSP70和P-gp的表达情况;并于热休克前1h应用不同浓度槲皮素作用于HepG2细胞,观察其热休克后4h二者的表达。结果:(1)热休克诱导后,免疫组化显示细胞内HSP70表达增多,“核内迁移”;流式细胞术示HSP70阳性细胞数升高,4h达到最高(11.47%),较对照组(6.64%)升高近一倍(P<0.01),24h后回落到低值;P-gp阳性细胞数随HSP70升高后升高,12h达到最高值(96.31%),较对照组(33.95%)升高近两倍(P<0.01),24h后回落到低值。(2)热休克前应用槲皮素能有效抑制热休克诱导HSP70和P-gp的过量表达,以100～200μmol/L槲皮素作用明显(P<0.01),呈浓度依赖性。结论:热休克可诱导HepG2细胞HSP70和P-gp的过量表达,P-gp的表达可能与HSP70的表达有关;BACKGROUND &OBJECTIVE:Heat shock protein 70(HSP70)has been thoug ht to inhibit apoptosi s and reduce the effectiveness of hyperthermal therapy and chemother apy on cancer.However,the relation ship between HSP70and the drug resistanc e to chemotherapy has not been definited.P-g lycoprotein(P-g p)was a kind of protein that could decre ase the effectiveness of chemotherapy.In o rder to explore the relationship bet ween HSP70and P-g p,the human hepatocarc inoma line HepG2cells was induced by heat shock in vitro,and the inhibiting effect of quercetin on them was obs erved at the same time to seek the method incre asing the effectiveness of hyperthermal therapy on hepatocarcinoma.METHODS :HepG2cells were bathed in water at 42℃stably for 90minutes.The expres sion of HSP70and P-g p were detected a t0,2,4,8,12,and 24hours after 42℃heat shock using immunocytochemistry and flow cytometry(FCM).Furthermore,at 4hours later after heat shock,they were also detected in HepG2cells whi ch had been pretreated by quercetin i n different concentrations within an hour before 42℃heat shock.RESULTS :(1)Immunocytochemistry showed that HS P70overexpressed in the cells and'moved'from cytoplasm to nucleus and nucleo lus after heat shock.The percentag e of HSP70positive cells c ame to the climax(11.47%)at 4th hour and increased about 2folds compared with that of the control g roup(6.64%)(P<0.01).At the 24th hour after heat shock,it declined to a low level.The percentag e of cells with P-g p positive went up following HSP70after heat shock.It came to the climax(96.31%)at the 12th hour.And it increased abo ut 3folds compared with that of the control g ro up(33.95%)(P<0.01).(2)The overexpression of HSP70and P-g p ind uced by heat shock could be inhibited effectively by quercetin in a dose-d ependent manner,especially by quer cetin at the concentrations of 100-200μmol /L(P<0.01).CONCLUSION:(1)The overexpression of HSP70and P-g p in HepG2cells can be induced by heat shock and P-g p maybe has a correlation with HSP70.(2)The overexpr

关 键 词：热休克 诱导 人肝癌HEPG2细胞 HSP70 P-GP 表达 槲皮素 抑制作用 

分 类 号：R735.7[医药卫生—肿瘤] R73-34[医药卫生—临床医学]