Expression of MRP1 in human NSCLC tissues and its relationship with resistance to DDP

OBJECTIVE: To observe the expression of multidrug resistance-associated protein 1(MRP1) in the human NSCLC cell line A549 with resistance to cisplatin(A549/DDP),so as to investigate the relationship between MRP1 and the human NSCLC cell with resistance to DDP.METHODS: Cultured two cell lines of A549 and A549/DDP which were from the same uterine.The growth curves of the two cell lines were drawn and their chemoresistance indexes were measured by methyl tetrazolium(MTT) assay.The expression levels of MRP1 mRMA in the two cell lines were observed by reverse transcription polymerase chain reaction(RT-PCR).RESULTS: The chemoresistance index for A549 and A549/DDP were 0.65 μg/mL and 3.7 μg/mL,respectively.As a result,the resistance of A549/DDP to DDP was 5.5-fold greater than that of A549,and the expression of MRP1 was significantly up-regulated in A549/DDP(P0.05).CONCLUSIONS: The expression of MRP1 in A549/DDP was up-regulated,whereas was down-regulated or none in A549.It shows that the overexpression of MRP1 has relation to the human lung cell with resistance to DDP,and provides the theory basis for reversing the sensitivity of DDP by decreasing the transcription of MRP1 mRNA.