E2A-Pbx1 Induces Growth, Blocks Differentiation, and Interacts with Other Homeodomain Proteins Regulating Normal Differentiation
Arrested differentiation is a hallmark of progenitor cell leukemias as well as many other types of human cancer. It is hypothesized that such progenitor cell cancers express oncoproteins that block differentiation. The E2A-Pbx1 oncoprotein that results from the t(1;19) chromosomal translocation of childhood pre-B cell acute lymphoblastic leukemia (pre-B ALL) is a fascinating oncoprotein because it blocks differentiation and physically interacts with homeodomain proteins, which are effectors of normal differentiation. These properties suggest the attractive hypothesis that E2A-Pbx1 blocks pre-B cell differentiation by interfering with the ability of other homeodomain proteins to orchestrate terminal B cell differentiation.
KeywordsAcute Lymphoblastic Leukemia Homeobox Gene Normal Differentiation Cooperative Binding Homeodomain Protein
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