To explore how As2O3 induced differentiation of CD133+ HCC CSCs, we analyzed stem cell signaling–related gene expression by using a Human Stem Cell Signaling RT2 Profiler PCR Array after the CD133+ Huh7-wt cells had been treated with 4 μM As2O3 for 48 hours. This evidence concerns the gene PROM1 and hepatocellular carcinoma.