PROM1 and hepatocellular carcinoma: CD133 is a main marker of CSCs with strong cell penetration and GPC3 is a superior HCC marker with high expression.32 Since GPC3 antigens are widely present on the surface of HCC cells, the GPC3 branch interacted considerably with GPC3+ HCC cells to anchor CoG133-CAR T cells at the tumor and accumulate effector cells around the tumor.