PARP1 and prostate neoplasm: In agreement with the negative regulation of TGF-β signaling by PARP1, prostate tumors developing in a mouse carrying complete loss of function mutation of PARP1 revealed enhanced epithelial-mesenchymal transition caused by enhanced TGF-β signaling in the prostate carcinoma cells (26), which corroborates our original findings whereby PARP1 impacted the mesenchymal transition of mammary epithelial cells (22).