PROM1 and breast cancer: Indeed, we found that Hallmark gene sets related to cell proliferation: E2F Targets (NES = −1.77, FDR = 0.05), G2M Checkpoint (NES = −1.52, FDR = 0.11), and MYC Targets V1 (NES = −1.64, FDR = 0.07) were all significantly enriched in CD133-low BC in the TCGA cohort (Fig. 3A).