To further validate that PTEN-mediated synthetic lethality to AA could apply to other cancers; two p300/CBP inhibitors, AA and C646 in a pair of prostate cancer cell lines with different PTEN status: 22RV1 (PTEN wild-type, PTEN+/+) and PC3 (PTEN null, PTEN-/-). This evidence concerns the gene EP300 and cancer.