Because chemotherapy failure can lead to cancer recurrence and death, the role of persistent CerS4 overexpression in the alteration of the chemoresistance properties of MCF-7 cells was examined by evaluating the impact of CerS4 overexpression on the responses of MCF-7 cells to the anticancer drugs doxorubicin, paclitaxel, and tamoxifen. This evidence concerns the gene CERS4 and cancer.