Treatment with naturally occurring antioxidants, such as vitamin C or phenethyl isothiocyanates (PEITCs), found in broccoli or Brussel sprouts, also diminished self-renewal capacity and clonogenicity of NCCIT human embryonic carcinoma and human colon cancer cell lines, and reduced CD133+, EpCAM+ and OV6+ cells while inhibiting tumorspheres formation and growth of hepatocellular carcinoma cell lines and PDX models in vivo (Yun et al., 2017; Lv et al., 2018). This evidence concerns the gene PROM1 and hepatocellular carcinoma.