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.
He
Qun
Q
Research Laboratory of Blood Physiology, Department of Physiology, Xiangya School of Medicine, Central South University, Changsha 410078, China. hequn888@yahoo.com
Li
Qiong
Q
Yuan
Lin-bo
LB
He
Jun
J
D002454:Cell Differentiation / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects; D004268:DNA-Binding Proteins / Q000235:genetics*; D051766:Early Growth Response Protein 1; D015973:Gene Expression Regulation, Leukemic / Q000187:drug effects*; D018922:HL-60 Cells; D006801:Humans; D017874:Immediate-Early Proteins / Q000235:genetics*; D020014:K562 Cells; D051258:MafB Transcription Factor; D015513:Oncogene Proteins / Q000235:genetics*; D013256:Steroids / Q000494:pharmacology*; D014157:Transcription Factors / Q000235:genetics*; D015854:Up-Regulation
D004268:DNA-Binding Proteins; C497325:EGR1 protein, human; D051766:Early Growth Response Protein 1; C500140:H 89712; D017874:Immediate-Early Proteins; C490407:MAFB protein, human; D051258:MafB Transcription Factor; D015513:Oncogene Proteins; D013256:Steroids; D014157:Transcription Factors