SMAD4 and breast cancer: Of these stage-specific microRNAs, miR-183, which was specific to CSII, is considered an oncogene because it targets DKK3, SMAD4, EGR1, PTEN and the PI3K pathway, and it is frequently described in breast cancer as well as other reproductive system related-cancers such as prostate, ovarian and urothelial carcinomas[52, 53].