PROM1 and liver cancer: To understand if UNC0642 treatment could improve CAR-T cell cytotoxicity, we investigated the effect of UNC0642 on CAR-T cells targeting CD133 (Fig. 7A), expressed by cancer stem cells originating from various epithelial cells34, including the liver cancer cell line Hep3B (99.6 % CD133+; Supplementary Fig. 6B).