Overexpression of CtBP is often associated with processes such as epithelial-mesenchymal transition (EMT) and self-renewal of tumor stem cells [3,4], which promotes the development and progression of a variety of tumors, such as hepatocellular carcinoma, prostate cancer, gastric cancer, breast cancer, etc. Vertebrates possess two homologous CtBP genes, which encode distinct proteins: CtBP1 and CtBP2. Here, CTBP1 is linked to breast cancer.