SIRT1 and gastric cancer: Deng et al. (2021) reported that miR-34a-5p reversed multidrug resistance in gastric cancer cells by targeting the 3′-UTR of Sirtuin 1 (SIRT1) and inhibiting its expression. Wang et al. (2020) demonstrated that miR-34a-5p is bound to the 3′-UTR of lymphoid enhancer-binding factor 1 (LEF1). miR-34a-5p overexpression inhibited the proliferation and invasion of esophageal squamous cell carcinoma (ESCC) cells. The rescue experiments showed that the re-expression of LEF1 reversed the inhibitory effect of miR-34a-5p (Wang et al., 2020).