Expression of Ten ABC Transporters in Cisplatin-resistant Nasopharyngeal Carcinoma Cell Lines / 生物化学与生物物理进展

ABSTRACT

Ten ATP binding cassette (ABC) transporters are confirmed to be associated with resistance against anticancer drugs. To investigate the relationship between these ten ABC transporters and the nasopharyngeal carcinoma cell line CNE2 resistant to cisplatin, cisplatin and cisplatin with 5-fluorouracil were used to induce the CNE2 cell to acquire the drug-resistance for 1 year. After these cells were cultured without drugs for 2 months, the MTT assay method was used to determine the dose-effect relationship of cisplatin and resistant index. Quantitative real time polymerase chain reaction was used to detect the mRNA expression of ten ABC transporters in CNE2 and the drug-resistant CNE2 cells, and the result was confirmed by immunocytochemical method. The results of MTT method showed that two cell lines resistant to cisplatin (named as CNE2/DDP) and cisplatin with 5-fluorouracil (named as CNE2/DDP+5Fu) were established, with resistant index 2.58 and 5.31, respectively. Of ten ABC transporters, only ABCC2 was found to be up-regulated both in CNE2/DDP and CNE2/DDP+5Fu cells, for increasing about 2.50 and 4.08 folds, respectively. The results of immunocytochemical method also confirmedthat the expression of ABCC2 in CNE2/DDP and CNE2/DDP+5Fu cells were stronger that that in CNE2 cell. Furthermore, ABCC2 protein was found to be located at nuclear membrane of CNE2/DDP +5Fu cell but not at nuclear membrane of CNE2 cell. The results suggest that ABCC2 may play an important role in cisplatinresistance of nasopharyngeal carcinoma cell line CNE2.