TGFB1 and hepatocellular carcinoma: All-trans retinoic acid (ATRA), a known pan-retinoic receptor agonist, has been found to regulate EMT and inhibit migration in breast cancer via the TGF-β pathway [63], a notion that might support the use of RARB agonists against poorly differentiated HCC with TGF-β-dependent EMT features.