PEBP1 and prostate carcinoma: Consistent with these observations, the polycomb protein EZH2 was reported to promote the invasion of breast and prostate cancers via suppression of RKIP transcription [25], and RKIP has been demonstrated to inhibit metastasis of multiple human cancers, including prostate, breast, melanoma, and colorectal cancers, and gastrointestinal stromal tumors [26-32].