SMAD4 and urinary bladder cancer: miR-1305, which targets POLR3G (downstream target of OCT4 and NANOG, pluripotency markers), regulates the differentiation of human embryonic stem cells (Overexpression of miR-1305 was shown to induce cell differentiation, whereas miR-1305 knockdown supports the maintenance of pluripotency of human embryonic stem cells; Jin et al., 2016)miR-1305 mimic significantly reduced the expression and activity of TGF-β2 in bladder cancer cells (Su et al., 2020)miR-1305 was shown to target Smad4 in TGF-β pathway, and Smad4 was shown to be critical for chondrogenesis (Zhang et al., 2017)