Gene expression analysis of OVCAR-3 and CDK2 resistant sublines

Cyclin E1 (CCNE1) is amplified in various tumor types including high-grade serous ovarian cancer where it is associated with poor clinical outcome. We have demonstrate that suppression of the Cyclin E1 partner kinase, CDK2, induces apoptosis in a CCNE1 amplicon-dependent manner. Little is known of mechanisms of resistance to CDK inhibitors. We therefore generated OVCAR-3 sublines with reduced sensitivity to CDK2 inhibitors and profiled by gene expression microarrays. Arrayed samples included parental OVCAR-3 cells (n = 4 replicates) and five independently derived sublines resistant to PHA-533533 (OVCAR3-533533-R1, -R3, -R5, -R6, -R7). The resistant cell lines were arrayed after drug selection (P5) and after continued passage in the absence of inhibitor (P10+).