PAX5 is a tumor suppressor in B-ALL, while the role of PAX5 fusion proteins in B-ALL development is largely unknown. Here we studied the function of PAX5-ETV6 and PAX5- FOXP1 in mice expressing these proteins from the Pax5 locus. Both proteins arrested Blymphopoiesis at the pro-B-to-pre-B cell transition and, contrary to their proposed dominantnegative role, did not interfere with the expression of most Pax5 target genes. Pax5-Etv6, but not Pax5-Foxp1, cooperated with loss of the Cdkna2a/b tumor suppressor in promoting B-ALL development. Regulated Pax5-Etv6 target genes identified in these B-ALLs encode proteins implicated in pre-BCR signaling and migration/adhesion, which could contribute to the proliferation, survival and tissue infiltration of leukemic B-cells. Together with similar observations made in human PAX5-ETV6+ B-ALLs, these data identified PAX5-ETV6 as a potent oncoprotein. SOURCE: Maria FischerBusslinger Group Research Institute of Molecular Pathology

Pluto Bioinformatics

GSE84987: Molecular role of the PAX5-ETV6 oncoprotein in promoting B cell acute lymphoblastic leukemia