MDM2 and neoplasm: Conversely, it has been reported that some RPs including RPL5 (36, 37), RPL11 (37–39), RPL23 (36, 40), and RPS7 (41) interact with MDM2 or HDM2, an E3 ubiquitin ligase for p53 protein, and stabilize p53 protein, suggesting that these RPs play a tumor suppressor role.