期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1999
卷号：96
期号：22
页码：12804-12809
DOI：10.1073/pnas.96.22.12804
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Primitive subsets of leukemic cells isolated by using fluorescence-activated cell sorting from patients with newly diagnosed Ph+/BCR-ABL+ chronic myeloid leukemia display an abnormal ability to proliferate in vitro in the absence of added growth factors. We now show from analyses of growth-factor gene expression, protein production, and antibody inhibition studies that this deregulated growth can be explained, at least in part, by a novel differentiation-controlled autocrine mechanism. This mechanism involves the consistent and selective activation of IL-3 and granulocyte colony-stimulating factor (G-CSF) production and a stimulation of STAT5 phosphorylation in CD34+ leukemic cells. When these cells differentiate into CD34- cells in vivo, IL-3 and G-CSF production declines, and the cells concomitantly lose their capacity for autonomous growth in vitro despite their continued expression of BCR-ABL. Based on previous studies of normal cells, excessive exposure of the most primitive chronic myeloid leukemia cells to IL-3 and G-CSF through an autocrine mechanism could explain their paradoxically decreased self-renewal in vitro and slow accumulation in vivo, in spite of an increased cycling activity and selective expansion of later compartments.
