摘要
背景与目的:三氧化二砷(arsenic trioxide,As2O3)作为治疗实体瘤的新药已应用于临床,但其作用机理尚不清楚。本研究拟探讨As2O3对肝癌SMMC-7721细胞增殖的影响,及其对细胞周期素依赖性激酶抑制剂(cyclin-dependent kinase inhibitors,CDKIs)P27kip1和P27kip1相关蛋白c-Jun结合蛋白-1(c-Jun activation domain-binding protein1,JAB1)表达的调控作用。方法:体外培养人肝癌细胞株SMMC-7721,用0～8μmol/LAs2O3处理96h,用WST-8法检测细胞的存活率。用2!mol/LAs2O3作用72h,在指点时间点收集细胞,用Westernblot技术检测P27kip1、JAB1在SMMC-7721细胞中的表达,同时采用核浆分离方法及细胞免疫荧光技术检测P27kip1、JAB1表达和亚细胞定位的改变。结果:与对照组比较,As2O3可明显抑制SMMC-7721细胞的增殖,96h时IC50为(1.81±0.41)μmol/L。2μmol/LAs2O3处理12h后,SMMC-7721细胞中P27kip1蛋白表达增加,而JAB1蛋白表达减少。在As2O3处理后12h、24h,P27kip1与JAB1均发生从胞浆向胞核的易位。免疫荧光检测P27kip1和JAB1的亚细胞定位情况,结果也显示2μmol/LAs2O3可诱导两者在胞核的积聚。结论:As2O3可下调JAB1的表达,从而影响P27kip1的核内外分布及表达,并影响P27kip1的功能状态,进而参与调控肝癌细胞的增殖。
BACKGROUND ＆ OBJECTIVE. Arsenic trioxide （As2O3） is a new drug used to treat solid tumors. However, the mechanism is still unclear. This study was to investigate the effects of As2O3 on the proliferation of human hepatocellular carcinoma （HCC） cell line SMMC-7721, and to explore the mechanisms. METHODS. When treated with 0-8 μmol/L As2O3 for 96 h, the survival rate of SMMC-7721 cells was determined by WST-8 assay. When treated with 2 μmol/L As2O3 for 72 h, the expression of P27^kip1 and c-Jun activation domain-binding protein 1 （JAB1） in SMMC-7721 cells were detected at different time points by Western blot, the subcellular localization of P27^kip1 and JAB1 was detected by subcellular fractionation and immunofluorescent staining. RESULTS. As2O3 significantly inhibited the proliferation of SMMC- 7721 cells. The 50% inhibition concentration （IC50） of As2O3 to SMMC-7721 cells was （1.81 ±0.41） μmol/L at 96 h. When SMMC-7721 cells were treated with 2 μmol/L As2O3 for 12 h, the expression of JAB1 was down-regulated and that of P27^kip1 was up-regulated. Furthermore, P27^kip1 and JAB1 proteins were translocated from the cytoplasm into nuclei when cells were exposed to 2 μmol/L As2O3 for 12 h and 24 h, respectively. The nuclear accumulation of both proteins was also observed under fluorescence microscope after treatment of 2 μmol/L As2O3. CONCLUSION. As2O3 attenuates JAB1 expression, thereby disturbs the location and expression of P27^kip1, and may participate in regulating the proliferation of SMMC-7721 cells through interfering with the function of P27^kip1.
出处
《癌症》
SCIE
CAS
CSCD
北大核心
2007年第12期1304-1308,共5页
Chinese Journal of Cancer
基金
国家自然科学基金(No.30300099
No.30770488)
江苏省自然科学基金(No.BK2003035)
江苏省高校自然科学研究项目(No.04KJB320114)
江苏省科技指导性计划(No.BS2004526)
"六大人才高峰"资助项目
江苏省卫生科研项目(No.H200632)
南通社会发展科技项目(No.S2007041)~~
作者简介
通讯作者：沈爱国 Tel：86—513—85051736,Fax：86—513—85051999,E—mail：shag_888@yahoo．com．cn
