PTOV1 and prostate neoplasm: We have shown that PTOV1 in metastatic prostate tumors is significantly overexpressed and represses the transcription of the downstream targets of Notch, the HES1 and HEY1 genes, by interacting with SMRT, RBP-Jκ, NCoR, HDAC1 and HDAC4 (Figure 3) [32].