A new 2-aminosteroid induces cellular differentiation and upregulates the expression of MafB and Egr-1 genes respectively in HL-60 and K562 leukemia cells

BACKGROUND: In previous work, we suggested that some 2-aminosteroids inhibited proliferation and induced differentiation of both human and murine leukemia cells. Here, we reported the actions of another new 2-aminosteroid designated as H89712 on human leukemia cells. METHODS: Cell colony counting and MTT assay were used to determine proliferation. Cell morphology, histochemical staining, UV detection and cytometry were used to determine differentiation. RT-PCR was used to detect gene expression. Standard statistical method was used to analyze data. RESULTS: H89712 inhibited proliferation of HL-60 leukemia cells and the inhibition percentage in MTT assay was 18% at the dose of 10(-8) mol/L and 65% at the dose of 10(-5) mol/L, respectively. The inhibition for HL-60 in colony assay was 23% at the dose of 10(-8) mol/L and 96% at the dose of 10(-5) mol/L, respectively. H89712 also induced HL-60 cells toward macrophage-like differentiation. It was verified by flow cytometry that the percentage of positive CD14 expression in differentiated HL-60 cells was about 9 times higher than that of the control at the dose of 10(-8) mol/L and 20 times higher than that of the control at the dose of 10(-5) mol/L respectively, and this action involved upregulation of MafB gene in HL-60 leukemia cells. On the other hand, H89712 inhibited proliferation of K562 leukemia cells and the inhibition of K562 leukemia cells in MTT assay was shown by 34% at the dose of 10(-8) mol/L and 88% at the dose of 10(-5) mol/L respectively. The inhibition of K562 leukemia cells in colony assay was 53% at the dose of 10(-8) mol/L and 100% at the dose of 10(-5) mol/L respectively. H89712 also induced K562 cells toward erythroid-like differentiation and it was verified by flow cytometry that the percentage of positive CD71 expression in differentiated K562 cells was about 9 times higher than that of the control at the dose of 10(-8) mol/L and 16 times higher than that of the control at the dose of 10(-5) mol/L respectively. This action was related to upregulation of Egr-1 gene in K562 leukemia cells. CONCLUSIONS: Our results showed the important roles played by MafB in macrophage differentiation and Egr-1 in erythroid differentiation of human myeloid leukemia cells.