Expression data from two breast cancer cell lines

During cancer progression, carcinoma cells encounter a variety of cytotoxic stresses such as hypoxia, nutrient deprivation, and low pH as a result of inadequate vascularization. To maintain survival and growth in the face of these physiologic stressors, a set of adaptive response pathways are induced. One adaptive pathway well studied in other contexts is the unfolded protein response (UPR), of which XBP1 is an important component. We used microarrays to detect transcriptome profile changes after XBP1 knockdown in breast cancer cell lines, and identify genes and pathways regulated by XBP1, which could help elucidate how XBP1 mediates the adaptive response of breast cancer to cytotoxic stresses. We extracted RNA and hybridized it to Affymetrix microarrays in two breast cancer cell lines (T47D and MDA-MB-231) under treated (hypoxia and glucose deprivation) or untreated conditions with XBP1 knockdown or not.