Cisplatin-induced gene expression changes in triple-negative breast cancer (TNBC) cells

Breast cancers lacking receptors for estrogen, progesterone or HER2 on their cell surface are called triple-negative breast cancers (TNBCs). TNBCs account for ~15-20% of all invasive breast cancers and do not benefit from anti-hormonal or anti-HER2 treatments. Although patients with TNBC can initially respond to chemotherapy, they do have worse overall prognosis compared to other breast cancer subtypes. Unfortunately, TNBCs lack clear targetable ‘driver’ oncogenes. Thus, there is an unmet need for strategies to improve the therapeutic options for these patients. We used microarrays to assess differences in gene expression in triple-negative breast cancer cells in response to the platinum-based chemotherapeutic agent cisplatin. The purpose was to find drug induced changes in gene expression level that could differentiate cisplatin sensitive from cisplatin resistant TNBC cell lines. Four triple-negative breast cancer cell lines, MDA-MB-231, MDA-MB-157, BT549 and HCC38, were treated with 2 µM cisplatin for 0, 24 or 72 hours. Two independent replicates were collected for each cell line.