CDKN1A and gastric cancer: A follow-up study from the same group investigated the cellular mechanisms involving miR-17-5p in gastric cancer and found that miR-17-5p/20a promote gastric cancer by directly targeting the tumor suppressors p21 and p53-induced nuclear protein 1 (TP53INP1), which results in unrestrained proliferation and apoptosis inhibition, respectively, and involve a positive regulatory circuit between miR-17-5p/20a and MDM2 (murine double minute 2).