KLF4 and prostate cancer: Castration-resistant prostate cancer cells with high levels of the deubiquitinase DUB3 and NUT midline carcinoma cells with high levels of KLF4 are resistant to BRD4 inhibitors, because DUB3 binds to BRD4 and augments its deubiquitination and stabilization and KLF4 up-regulates E2F and MYC gene expression [45, 46].