TGFB1 and hepatocellular carcinoma: Given our observation that HCC-derived CSCs exhibit a mesenchymal phenotype and have a close association with EMT during the activation of TGF-β1 signalling in Hep3B and PLC/PRF/5-derived spheres, we hypothesise that EMT may be responsible for maintaining tumour growth and therapy resistance in Hep3B and PLC/PRF/5-derived CSCs.