K562耐药细胞的建立及相关蛋白表达改变的研究

DEVELOPMENT OF A K562 MULTIDRUG-RESISTANT CELL LINE AND STUDY ON PROTEINS WITH ALTERED EXPRESSION

为研究肿瘤细胞发生多药耐药后蛋白整体水平表达的改变,将K562细胞与阿霉素(ADR)共同培养,逐渐增加药物浓度,最后建立耐阿霉素的细胞K562/ADR株。MTT法检测阿霉素(ADR)、顺铂(DDP)、5-氟尿嘧啶(5-FU)和长春新碱(VCR)对K562和K562/ADR细胞的半数抑制率(IC_(50))。利用蛋白质组学技术,通过双向凝胶电泳分离K562和K562/ADR细胞的总蛋白,银染显色,分析差异蛋白,对部分蛋白点进行胶内酶解,用基质辅助激光解析飞行时间质谱法得肽质量指纹图谱,用AutoMS-Fit软件查询NCBInr数据库鉴定蛋白质。结果表明K562细胞经ADR诱导后出现多药耐药现象,ADR、DDP、5-FU和VCR对K562/ADR细胞的IC_(50)明显高于K562。将K562和K562/ADR的双向电泳图谱进行差异比较,初步鉴定仅在K562/ADR图谱上出现的蛋白是一些与细胞分裂、基因转录有关的蛋白质。这些蛋白的变化与耐药细胞的特性相关,可能与临床化疗的多药耐药现象有联系。

In an attempt to study the whole protein expression alterations of tumer cells after becoming multidrug-resistant, which may provide useful information on new drug target identification, an adriamycin-resistant variant of the human leukemia cell line K562 (K562/ADR) was developed in vitro by continuous exposure to adrimycin. MTT assay was used to determine IC50 of K562/ADR cells to adriamycin (ADR), cisplatin (DDP), 5-fluorouracil (5-FU) and vincristin (VCR). The total proteins of K562 and K562/ADR were seperated by two-dimensional gel electrophoresis and visualized by silver staining. Proteins with significant expression alterations were selected and their peptide mass fingerprints (PMFs) were obtained by matrix-assisted laser desorption/ionization time of flying mass spectrometry (MALDI-TOF-MS). The PMFs were used to search NCBInr database by AutoMS-Fit software. The results showed that K562/ADR cell demonstrated cross-resistance to other antineoplas-tic drugs. The IC50 of K562/ADR cells to ADR, DDP, 5-FU, VDR were much higher than those of K562. The proteins differentially expressed in the two cell lines were identified as cell cycle-related proteins, zinc finger protein 165, etc. These proteins are involved in cell cycling and transcription regulation, whose expression alterations may contribute to the multidrug resistant phenotype of K562/ ADR cells.