In this paper, we discuss potential drug repositioning as a new therapeutic strategy for gynecologic tumors, including peroxisome proliferator-activated receptor (PPAR) ligands and ritonavir for treatment of ovarian cancer, metformin for treatment of endometrial cancer, and cyclooxygenase-2 (COX-2) inhibitors for cervical cancer. This evidence concerns the gene PTGS2 and endometrial cancer.