Expression microarray analysis reveals genes associated with in vitro resistance to cisplatin in a cell line model

We aimed to investigate the mechanisms of cisplatin resistance using an in vitro cancer model. A derivative breast cancer cell line (MCF-7CR) was established which demonstrated significant resistance to cisplatin at clinically relevant low concentrations compared to the MCF-7 parental cell line. Expression microarray analysis was used to identify targets from a 3k cancer-related oligonucleotide platform which were differentially expressed between the derivative and parental cell lines. Real-time quantitative PCR was used to confirm the difference in expression of a subset of genes which demonstrated significant up- or down-regulation. Using expression microarray analysis a total of 28 genes were identified to be differentially expressed (by at least 2-fold) between the MCF-7 and MCF-7CR cells. Real-time quantitative PCR expression analysis confirmed the differential expression of a selection of these genes (ACTG2, ARHD, CTSL, GSTM3, GSTM4 and EHF) between the two cell lines. An in vitro model of cisplatin resistance has been established and expression microarray analysis revealed 28 genes which may be associated with cisplatin resistance.