Mice Defective in Two Apoptosis Pathways in the Myeloid Lineage Develop Acute Myeloblastic Leukemia

Department of Pathology, Stanford University School of Medicine, California 94305, USA.
Immunity (Impact Factor: 21.56). 08/1998; 9(1):47-57. DOI: 10.1016/S1074-7613(00)80587-7
Source: PubMed


Fas-deficient (Fas(lpr/lpr)) mice constitutively expressing Bcl-2 in myeloid cells by the hMRP8 promoter often develop a fatal disease analogous to human acute myeloblastic leukemia (AML-M2). Hematopoietic cells from leukemic Fas(lpr/lpr)hMRP8bcl-2 animals form clonogenic blast colonies in vitro and can transfer disease to wild-type mice. In vitro ligation of Fas on Fas+/+ hMRP8bcl-2 marrow cells depletes approximately 50% of myeloid progenitor activity, demonstrating that Bcl-2 can only partially block Fas-mediated death signals in myelomonocytic progenitors. In addition, Fas(lpr/lpr) marrow contains greatly increased numbers of myeloid colony-forming cells as compared to Fas+/+ controls. Taken together, these data suggest that Fas has a novel role in the regulation of myelopoiesis and that Fas may act as a tumor suppressor to control leukemogenic transformation in myeloid progenitor cells.

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