To further elucidate the function of ICAT in the 1,25-(OH)2D3-mediated inhibition of AML cell stemness, we knocked out and overexpressed the ICAT gene in HL-60 cells and analyzed its role by western blotting, qRT-PCR, and cell sphere formation assays. The gene discussed is CTNNBIP1; the disease is acute myeloid leukemia.