title: β-Catenin activates the HOXA10 and CDX4 genes in myeloid progenitor cells.
abstract: HoxA10 is a homeodomain transcription factor that is involved in maintenance of the myeloid progenitor population and implicated in myeloid leukemogenesis. Previously, we found that FGF2 and CDX4 are direct target genes of HoxA10 and that HOXA10 is a Cdx4 target gene. We also found that increased production of fibroblast growth factor 2 (Fgf2) by HoxA10-overexpressing myeloid progenitor cells results in activation of β-catenin in an autocrine manner. In this study, we identify novel cis elements in the CDX4 and HOXA10 genes that are activated by β-catenin in myeloid progenitor cells. We determine that β-catenin interacts with these cis elements, identifying both CDX4 and HOXA10 as β-catenin target genes in this context. We demonstrate that HoxA10-induced CDX4 transcription is influenced by Fgf2-dependent β-catenin activation. Similarly, Cdx4-induced HOXA10 transcription is influenced by β-catenin in an Fgf2-dependent manner. Increased expression of a set of Hox proteins, including HoxA10, is associated with poor prognosis in acute myeloid leukemia. Cdx4 contributes to leukemogenesis in Hox-overexpressing acute myeloid leukemia, and increased β-catenin activity is also associated with poor prognosis. The current studies identify a molecular mechanisms through which increased expression of HoxA10 increases Cdx4 expression by direct CDX4 activation and by Fgf2-induced β-catenin activity. This results in Cdx4-induced HoxA10-expression, creating a positive feedback mechanism.
authors.affiliation: Feinberg School of Medicine and the Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Chicago, Illinois 60611, USA.
authors.forename: Ling
authors.initials: L
authors.lastname: Bei
authors.forename: Chirag
authors.initials: C
authors.lastname: Shah
authors.forename: Hao
authors.initials: H
authors.lastname: Wang
authors.forename: Weiqi
authors.initials: W
authors.lastname: Huang
authors.forename: Rupali
authors.initials: R
authors.lastname: Roy
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Eklund
mesh_terms: D000818:Animals; D016222:Fibroblast Growth Factor 2 / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation / Q000502:physiology*; D000080905:Homeobox A10 Proteins; D018398:Homeodomain Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D051379:Mice; D018345:Mice, Knockout; D023461:Myeloid Progenitor Cells / Q000166:cytology / Q000378:metabolism*; D020218:Response Elements / Q000502:physiology*; D014158:Transcription, Genetic / Q000502:physiology; D020298:U937 Cells; D051176:beta Catenin / Q000235:genetics / Q000378:metabolism*
chemical_list: C084563:Cdx4 protein, mouse; D000080905:Homeobox A10 Proteins; D018398:Homeodomain Proteins; D051176:beta Catenin; D016222:Fibroblast Growth Factor 2; C069634:HOXA10 protein, human; C092119:Hoxa10 protein, mouse