结肠癌TRAIL耐药细胞株的建立及其耐药机制的初步研究  

Establishment of TRAIL Drug-Resistant Gene in Colon Cancer Cell Subline and Investigation of Its Resistance Mechanism

作　　者：陈琳琳[1] 朱玉萍[1] 宋章法[1] 黄学锋[1] 毛伟芳[1] 

机构地区：[1]浙江大学医学院附属邵逸夫医院肛肠外科,浙江杭州310016

出　　处：《癌变．畸变．突变》2006年第5期340-343,共4页Carcinogenesis,Teratogenesis & Mutagenesis

基　　金：国家自然科学基金(No.30572153);浙江省自然科学基金(No.Y205093)

摘　　要：背景与目的以人结肠癌DLD1细胞株为载体,探讨恶性肿瘤获得性TRAIL基因耐药的可能机制。材料与方法用重组腺病毒介导的TRAIL基因(Ad/gTRAIL)反复处理人结肠癌DLD1细胞,得到耐药细胞群DLD1-TRAIL/R。通过MTT比色法和蛋白电泳,检测耐药细胞对Ad/gTRAIL杀伤作用的敏感性及其凋亡通路中信号分子的表达情况,分析其获得性耐药的可能机制。结果DLD1-TRAIL/R细胞对Ad/gTRAIL和重组TRAIL蛋白处理耐药,但对腺病毒介导的Bax基因处理仍然敏感。耐药细胞内Bcl-XL的表达明显升高,caspase-8的表达显著下降,未见明显的caspase-8活性裂解形式。结论人结肠癌DLD1细胞株经Ad/gTRAIL反复处理后产生特异性针对TRAIL基因的耐药,其发生机制可能与Bcl-XL表达上调和caspase-8表达下调有关。BACKGROUND ＆ AIM： To evaluate the mechanisms involved in human colon cancer DLD1 cell line. MATERIAL AND METHODS： in acquiring the TRAIL drug-resistance gene DLD1 cells were repeatedly treated with adenovirus-mediated TRAIL gene（Ad/gTRAIL）, and DLD1-TRAIL/R cells resistant to Ad/gTRAIL were obtained. The cell growth was measured by MTT method. The expression of proteins involved in TRAIL-mediated apoptosis pathway was also showed by western blot analysis. Then the possible mechanisms involved in acquiring resistance were analyzed. RESULTS： DLD1-TRAIL/R cells resistant to TRAIL were obtained from TRAIL-sensitive DLD1 parent cells. But they were still sensitive to adenovirus-mediated Bax gene therapy. Further studies demonstrated that expression of Bcl-XL was dranlatically increased whereas caspase-8 was significantly decreased in DLD1-TRAIL/R cells. Simultaneously, there was no cleaved caspase-8 found in the DLD1-TRAIL/ R cells. CONCLUSION： After repeated treatment, DLD1 cells could acquire the specific resistance to TRAIL gene. The involved mechanisms may involve upegulation of Bcl-XL and down-regulation of caspase-8.

关 键 词：TRAIL 基因治疗 耐药 

分 类 号：R730.53[医药卫生—肿瘤]