As a result of these studies, we identified several gene networks that reflect the hyperthermic response of breast cancer and mammary epithelial cells (including cell cycle, heat shock, survival/apoptosis, DNA damage and Rab/Ran regulation) and that clearly differentiate the response of breast cancer cells from that of mammary epithelial cells (including mitotic regulation and expression of histone and non-protein coding RNAs). Here, RAN is linked to breast cancer.