miRNAs play a key role in the regulation of gene networks in mammalian cells. However, little is known about their roles and functions in the apoptosis pathway. Here, we conducted a whole-genome miRNA screening for apoptosis and identified more than 100 miRNAs as apoptosis inducers. To further explain the roles of these mRNAs in apoptosis, a second round of screening was conducted between p53 +/+ and -/- cells. Among the hits, miR-596 was identified as a regulator of p53. The overexpression of miR-596 significantly increased p53 at the protein level, thereby inducing apoptosis. We also demonstrated that Smurf1 was the direct target of miR-596. Previously, Smurf1 was reported to attenuate the level of p53 through binding and stabilizing MDM2, a p53 inhibitor. Consequently, by targeting Smurf1, miR-596 indirectly increased the p53 level in mammalian cells. Moreover, our study demonstrated that miR-596 had other antitumor characteristics, such as inhibiting migration and proliferation. The data from the GEO dataset revealed that the high expression of miR-596 contributed to survival benefits among cancer patients. These results make miR-596 a potential antitumor factor for future biomedical applications.
Keywords: apoptosis; high-content screening; miR-596; p53.