IGF1-Mediated HOXA13 Overexpression Promotes Colorectal
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Original Article Upregulation of HOXA13 As a Potential Tumorigenesis and Progression Promoter of LUSC Based on Qrt-PCR and Bioinformatics
Int J Clin Exp Pathol 2017;10(10):10650-10665 www.ijcep.com /ISSN:1936-2625/IJCEP0065149 Original Article Upregulation of HOXA13 as a potential tumorigenesis and progression promoter of LUSC based on qRT-PCR and bioinformatics Rui Zhang1*, Yun Deng1*, Yu Zhang1, Gao-Qiang Zhai1, Rong-Quan He2, Xiao-Hua Hu2, Dan-Ming Wei1, Zhen-Bo Feng1, Gang Chen1 Departments of 1Pathology, 2Medical Oncology, First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi Zhuang Autonomous Region, China. *Equal contributors. Received September 7, 2017; Accepted September 29, 2017; Epub October 1, 2017; Published October 15, 2017 Abstract: In this study, we investigated the levels of homeobox A13 (HOXA13) and the mechanisms underlying the co-expressed genes of HOXA13 in lung squamous cancer (LUSC), the signaling pathways in which the co-ex- pressed genes of HOXA13 are involved and their functional roles in LUSC. The clinical significance of 23 paired LUSC tissues and adjacent non-tumor tissues were gathered. HOXA13 levels in LUSC were detected by quantita- tive real-time polymerase chain reaction (qRT-PCR). HOXA13 levels in LUSC from The Cancer Genome Atlas (TCGA) and Oncomine were analyzed. We performed receiver operator characteristic (ROC) curves of various clinicopath- ological features of LUSC. Co-expressed of HOXA13 were collected from MEM, cBioPortal and GEPIA. The func- tions and pathways of the most reliable overlapped genes were achieved from the Gene Otology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, respectively. The protein-protein interaction (PPI) net- works were mapped using STRING. HOXA13 in LUSC were markedly upregulated compared with those in the non- cancerous controls as demonstrated by qRT-PCR (LUSC: 0.330±0.360; CONTROLS: 0.155±0.142; P=0.021). -
Prospective Isolation of NKX2-1–Expressing Human Lung Progenitors Derived from Pluripotent Stem Cells
The Journal of Clinical Investigation RESEARCH ARTICLE Prospective isolation of NKX2-1–expressing human lung progenitors derived from pluripotent stem cells Finn Hawkins,1,2 Philipp Kramer,3 Anjali Jacob,1,2 Ian Driver,4 Dylan C. Thomas,1 Katherine B. McCauley,1,2 Nicholas Skvir,1 Ana M. Crane,3 Anita A. Kurmann,1,5 Anthony N. Hollenberg,5 Sinead Nguyen,1 Brandon G. Wong,6 Ahmad S. Khalil,6,7 Sarah X.L. Huang,3,8 Susan Guttentag,9 Jason R. Rock,4 John M. Shannon,10 Brian R. Davis,3 and Darrell N. Kotton1,2 2 1Center for Regenerative Medicine, and The Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA. 3Center for Stem Cell and Regenerative Medicine, Brown Foundation Institute of Molecular Medicine, University of Texas Health Science Center, Houston, Texas, USA. 4Department of Anatomy, UCSF, San Francisco, California, USA. 5Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA. 6Department of Biomedical Engineering and Biological Design Center, Boston University, Boston, Massachusetts, USA. 7Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, Massachusetts, USA. 8Columbia Center for Translational Immunology & Columbia Center for Human Development, Columbia University Medical Center, New York, New York, USA. 9Department of Pediatrics, Monroe Carell Jr. Children’s Hospital, Vanderbilt University, Nashville, Tennessee, USA. 10Division of Pulmonary Biology, Cincinnati Children’s Hospital, Cincinnati, Ohio, USA. It has been postulated that during human fetal development, all cells of the lung epithelium derive from embryonic, endodermal, NK2 homeobox 1–expressing (NKX2-1+) precursor cells. -
Homeobox Gene Expression Profile in Human Hematopoietic Multipotent
Leukemia (2003) 17, 1157–1163 & 2003 Nature Publishing Group All rights reserved 0887-6924/03 $25.00 www.nature.com/leu Homeobox gene expression profile in human hematopoietic multipotent stem cells and T-cell progenitors: implications for human T-cell development T Taghon1, K Thys1, M De Smedt1, F Weerkamp2, FJT Staal2, J Plum1 and G Leclercq1 1Department of Clinical Chemistry, Microbiology and Immunology, Ghent University Hospital, Ghent, Belgium; and 2Department of Immunology, Erasmus Medical Center, Rotterdam, The Netherlands Class I homeobox (HOX) genes comprise a large family of implicated in this transformation proces.14 The HOX-C locus transcription factors that have been implicated in normal and has been primarily implicated in lymphomas.15 malignant hematopoiesis. However, data on their expression or function during T-cell development is limited. Using degener- Hematopoietic cells are derived from stem cells that reside in ated RT-PCR and Affymetrix microarray analysis, we analyzed fetal liver (FL) in the embryo and in the adult bone marrow the expression pattern of this gene family in human multipotent (ABM), which have the unique ability to self-renew and thereby stem cells from fetal liver (FL) and adult bone marrow (ABM), provide a life-long supply of blood cells. T lymphocytes are a and in T-cell progenitors from child thymus. We show that FL specific type of hematopoietic cells that play a major role in the and ABM stem cells are similar in terms of HOX gene immune system. They develop through a well-defined order of expression, but significant differences were observed between differentiation steps in the thymus.16 Several transcription these two cell types and child thymocytes. -
The Phylogeny of Squamate Reptiles (Lizards, Snakes, and Amphisbaenians) Inferred from Nine Nuclear Protein-Coding Genes
C. R. Biologies 328 (2005) 1000–1008 http://france.elsevier.com/direct/CRASS3/ Evolution / Évolution The phylogeny of squamate reptiles (lizards, snakes, and amphisbaenians) inferred from nine nuclear protein-coding genes Nicolas Vidal a,b,∗, S. Blair Hedges a a Department of Biology and Astrobiology Research Center, 208 Mueller Lab., Pennsylvania State University, University Park, PA 16802-5301, USA b UMS 602, Taxonomie et collections, Reptiles–Amphibiens, département « Systématique et Évolution », Muséum national d’histoire naturelle, 25, rue Cuvier, Paris 75005, France Received 14 September 2005; accepted 3 October 2005 Available online 27 October 2005 Presented by Pierre Buser Abstract Squamate reptiles number approximately 8000 living species and are a major component of the world’s terrestrial vertebrate diversity. However, the established relationships of the higher-level groups have been questioned in recent molecular analyses. Here we expand the molecular data to include DNA sequences, totaling 6192 base pairs (bp), from nine nuclear protein-coding genes (C-mos, RAG1, RAG2, R35, HOXA13, JUN, α-enolase, amelogenin and MAFB) for 19 taxa representing all major lineages. Our phylogenetic analyses yield a largely resolved phylogeny that challenges previous morphological analyses and requires a new classification. The limbless dibamids are the most basal squamates. Of the remaining taxa (Bifurcata), the gekkonids form a basal lineage. The Unidentata, squamates that are neither dibamids nor gekkonids, are divided into the Scinciformata (scincids, xantusiids, and cordylids) and the Episquamata (remaining taxa). Episquamata includes Laterata (Teiformata, Lacertiformata, and Amphisbaenia, with the latter two joined in Lacertibaenia) and Toxicofera (iguanians, anguimorphs and snakes). Our results reject several previous hypotheses that identified either the varanids, or a burrowing lineage such as amphisbaenians or dibamids, as the closest relative of snakes. -
Catenin Signaling Regulate External Genitalia Formation As an Appendic
RESEARCH ARTICLE 3969 Development 136, 3969-3978 (2009) doi:10.1242/dev.039438 Dosage-dependent hedgehog signals integrated with Wnt/-catenin signaling regulate external genitalia formation as an appendicular program Shinichi Miyagawa1,2, Anne Moon3,*, Ryuma Haraguchi2,*, Chie Inoue4, Masayo Harada1, Chiaki Nakahara4, Kentaro Suzuki1, Daisuke Matsumaru4, Takehito Kaneko2, Isao Matsuo5, Lei Yang6, Makoto M. Taketo7, Taisen Iguchi8, Sylvia M. Evans9 and Gen Yamada1,4,† Embryonic appendicular structures, such as the limb buds and the developing external genitalia, are suitable models with which to analyze the reciprocal interactions of growth factors in the regulation of outgrowth. Although several studies have evaluated the individual functions of different growth factors in appendicular growth, the coordinated function and integration of input from multiple signaling cascades is poorly understood. We demonstrate that a novel signaling cascade governs formation of the embryonic external genitalia [genital tubercle (GT)]. We show that the dosage of Shh signal is tightly associated with subsequent levels of Wnt/-catenin activity and the extent of external genitalia outgrowth. In Shh-null mouse embryos, both expression of Wnt ligands and Wnt/-catenin signaling activity are downregulated. -catenin gain-of-function mutation rescues defective GT outgrowth and Fgf8 expression in Shh-null embryos. These data indicate that Wnt/-catenin signaling in the distal urethral epithelium acts downstream of Shh signaling during GT outgrowth. The current data also suggest that Wnt/-catenin regulates Fgf8 expression via Lef/Tcf binding sites in a 3Ј conserved enhancer. Fgf8 induces phosphorylation of Erk1/2 and cell proliferation in the GT mesenchyme in vitro, yet Fgf4/8 compound-mutant phenotypes indicate dispensable functions of Fgf4/8 and the possibility of redundancy among multiple Fgfs in GT development. -
Functional Genomics Atlas of Synovial Fibroblasts Defining Rheumatoid Arthritis
medRxiv preprint doi: https://doi.org/10.1101/2020.12.16.20248230; this version posted December 18, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. All rights reserved. No reuse allowed without permission. Functional genomics atlas of synovial fibroblasts defining rheumatoid arthritis heritability Xiangyu Ge1*, Mojca Frank-Bertoncelj2*, Kerstin Klein2, Amanda Mcgovern1, Tadeja Kuret2,3, Miranda Houtman2, Blaž Burja2,3, Raphael Micheroli2, Miriam Marks4, Andrew Filer5,6, Christopher D. Buckley5,6,7, Gisela Orozco1, Oliver Distler2, Andrew P Morris1, Paul Martin1, Stephen Eyre1* & Caroline Ospelt2*,# 1Versus Arthritis Centre for Genetics and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK 2Department of Rheumatology, Center of Experimental Rheumatology, University Hospital Zurich, University of Zurich, Zurich, Switzerland 3Department of Rheumatology, University Medical Centre, Ljubljana, Slovenia 4Schulthess Klinik, Zurich, Switzerland 5Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK 6NIHR Birmingham Biomedical Research Centre, University Hospitals Birmingham NHS Foundation Trust, University of Birmingham, Birmingham, UK 7Kennedy Institute of Rheumatology, University of Oxford Roosevelt Drive Headington Oxford UK *These authors contributed equally #corresponding author: [email protected] NOTE: This preprint reports new research that has not been certified by peer review and should not be used to guide clinical practice. 1 medRxiv preprint doi: https://doi.org/10.1101/2020.12.16.20248230; this version posted December 18, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. -
1714 Gene Comprehensive Cancer Panel Enriched for Clinically Actionable Genes with Additional Biologically Relevant Genes 400-500X Average Coverage on Tumor
xO GENE PANEL 1714 gene comprehensive cancer panel enriched for clinically actionable genes with additional biologically relevant genes 400-500x average coverage on tumor Genes A-C Genes D-F Genes G-I Genes J-L AATK ATAD2B BTG1 CDH7 CREM DACH1 EPHA1 FES G6PC3 HGF IL18RAP JADE1 LMO1 ABCA1 ATF1 BTG2 CDK1 CRHR1 DACH2 EPHA2 FEV G6PD HIF1A IL1R1 JAK1 LMO2 ABCB1 ATM BTG3 CDK10 CRK DAXX EPHA3 FGF1 GAB1 HIF1AN IL1R2 JAK2 LMO7 ABCB11 ATR BTK CDK11A CRKL DBH EPHA4 FGF10 GAB2 HIST1H1E IL1RAP JAK3 LMTK2 ABCB4 ATRX BTRC CDK11B CRLF2 DCC EPHA5 FGF11 GABPA HIST1H3B IL20RA JARID2 LMTK3 ABCC1 AURKA BUB1 CDK12 CRTC1 DCUN1D1 EPHA6 FGF12 GALNT12 HIST1H4E IL20RB JAZF1 LPHN2 ABCC2 AURKB BUB1B CDK13 CRTC2 DCUN1D2 EPHA7 FGF13 GATA1 HLA-A IL21R JMJD1C LPHN3 ABCG1 AURKC BUB3 CDK14 CRTC3 DDB2 EPHA8 FGF14 GATA2 HLA-B IL22RA1 JMJD4 LPP ABCG2 AXIN1 C11orf30 CDK15 CSF1 DDIT3 EPHB1 FGF16 GATA3 HLF IL22RA2 JMJD6 LRP1B ABI1 AXIN2 CACNA1C CDK16 CSF1R DDR1 EPHB2 FGF17 GATA5 HLTF IL23R JMJD7 LRP5 ABL1 AXL CACNA1S CDK17 CSF2RA DDR2 EPHB3 FGF18 GATA6 HMGA1 IL2RA JMJD8 LRP6 ABL2 B2M CACNB2 CDK18 CSF2RB DDX3X EPHB4 FGF19 GDNF HMGA2 IL2RB JUN LRRK2 ACE BABAM1 CADM2 CDK19 CSF3R DDX5 EPHB6 FGF2 GFI1 HMGCR IL2RG JUNB LSM1 ACSL6 BACH1 CALR CDK2 CSK DDX6 EPOR FGF20 GFI1B HNF1A IL3 JUND LTK ACTA2 BACH2 CAMTA1 CDK20 CSNK1D DEK ERBB2 FGF21 GFRA4 HNF1B IL3RA JUP LYL1 ACTC1 BAG4 CAPRIN2 CDK3 CSNK1E DHFR ERBB3 FGF22 GGCX HNRNPA3 IL4R KAT2A LYN ACVR1 BAI3 CARD10 CDK4 CTCF DHH ERBB4 FGF23 GHR HOXA10 IL5RA KAT2B LZTR1 ACVR1B BAP1 CARD11 CDK5 CTCFL DIAPH1 ERCC1 FGF3 GID4 HOXA11 IL6R KAT5 ACVR2A -
Integrative Bulk and Single-Cell Profiling of Premanufacture T-Cell Populations Reveals Factors Mediating Long-Term Persistence of CAR T-Cell Therapy
Published OnlineFirst April 5, 2021; DOI: 10.1158/2159-8290.CD-20-1677 RESEARCH ARTICLE Integrative Bulk and Single-Cell Profiling of Premanufacture T-cell Populations Reveals Factors Mediating Long-Term Persistence of CAR T-cell Therapy Gregory M. Chen1, Changya Chen2,3, Rajat K. Das2, Peng Gao2, Chia-Hui Chen2, Shovik Bandyopadhyay4, Yang-Yang Ding2,5, Yasin Uzun2,3, Wenbao Yu2, Qin Zhu1, Regina M. Myers2, Stephan A. Grupp2,5, David M. Barrett2,5, and Kai Tan2,3,5 Downloaded from cancerdiscovery.aacrjournals.org on October 1, 2021. © 2021 American Association for Cancer Research. Published OnlineFirst April 5, 2021; DOI: 10.1158/2159-8290.CD-20-1677 ABSTRACT The adoptive transfer of chimeric antigen receptor (CAR) T cells represents a breakthrough in clinical oncology, yet both between- and within-patient differences in autologously derived T cells are a major contributor to therapy failure. To interrogate the molecular determinants of clinical CAR T-cell persistence, we extensively characterized the premanufacture T cells of 71 patients with B-cell malignancies on trial to receive anti-CD19 CAR T-cell therapy. We performed RNA-sequencing analysis on sorted T-cell subsets from all 71 patients, followed by paired Cellular Indexing of Transcriptomes and Epitopes (CITE) sequencing and single-cell assay for transposase-accessible chromatin sequencing (scATAC-seq) on T cells from six of these patients. We found that chronic IFN signaling regulated by IRF7 was associated with poor CAR T-cell persistence across T-cell subsets, and that the TCF7 regulon not only associates with the favorable naïve T-cell state, but is maintained in effector T cells among patients with long-term CAR T-cell persistence. -
Expression of the Murine Hoxa4 Gene Requires Both Autoregulation and a Conserved Retinoic Acid Response Element
Development 125, 1991-1998 (1998) 1991 Printed in Great Britain © The Company of Biologists Limited 1998 DEV4970 Expression of the murine Hoxa4 gene requires both autoregulation and a conserved retinoic acid response element Alan I. Packer1,3, David A. Crotty1,3,*, Vivian A. Elwell3 and Debra J. Wolgemuth1-4,† 1Department of Genetics and Development and 2Obstetrics and Gynecology, 3The Center for Reproductive Sciences and the 4Columbia Cancer Center, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA *Present address: Department of Biology, California Institute of Technology, Pasadena, CA 91125, USA †Author for correspondence at address 1 (e-mail: [email protected]) Accepted 30 March; published on WWW 6 May 1998 SUMMARY Analysis of the regulatory regions of the Hox genes has flanking the Hoxd4 gene. Administration of retinoic acid to revealed a complex array of positive and negative cis-acting Hoxa4/lacZ transgenic embryos resulted in stage- elements that control the spatial and temporal pattern of dependent ectopic expression of the reporter gene in the expression of these genes during embryogenesis. In this neural tube and hindbrain. When administered to Hoxa4 study we show that normal expression of the murine Hoxa4 null embryos, however, persistent ectopic expression was gene during development requires both autoregulatory and not observed, suggesting that autoregulation is required for retinoic acid-dependent modes of regulation. When maintenance of the retinoic acid-induced expression. introduced into a Hoxa4 null background, expression of a Finally, mutation of the consensus retinoic acid response lacZ reporter gene driven by the Hoxa4 regulatory region element eliminated the response of the reporter gene to (Hoxa4/lacZ) is either abolished or significantly reduced in exogenous retinoic acid, and abolished all embryonic all tissues at E10.5-E12.5. -
Integrated Epigenome, Exome and Transcriptome Analyses Reveal Molecular Subtypes and Homeotic Transformation in Uterine Fibroids
bioRxiv preprint doi: https://doi.org/10.1101/452342; this version posted October 29, 2018. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. Integrated epigenome, exome and transcriptome analyses reveal molecular subtypes and homeotic transformation in uterine fibroids. Jitu W. George1*, Huihui Fan2*, Benjamin K. Johnson2, Anindita Chatterjee1, Amanda L. Patterson1, Julie Koeman4, Marie Adams4, Zachary B. Madaj3, David W. Chesla5, Erica E. Marsh6, Timothy J. Triche2, Hui Shen2#, Jose M. Teixeira1# 1Department of Obstetrics, Gynecology, and Reproductive Biology, College of Human Medicine, Michigan State University, Grand Rapids, MI, USA 2Center for Epigenetics, Van Andel Research Institute, Grand Rapids, MI, USA 3 Bioinformatics and Biostatistics Core, Van Andel Research Institute, Grand Rapids, MI, USA 4Genomics Core, Van Andel Research Institute, Grand Rapids, MI, USA 5Spectrum Health Universal Biorepository, Spectrum Health System, Grand Rapids, MI, USA 6Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, University of Michigan Medical School, Ann Arbor, MI, USA #Corresponding Authors: Hui Shen, PhD, Van Andel Research Institute, 333 Bostwick Ave NE, Grand Rapids, MI 49503. email [email protected] Jose M. Teixeira, PhD, Michigan State University, 400 Monroe Ave NW, Grand Rapids, MI 49503. email: [email protected] Funding: This work was supported by grant HD072489 from the National Institute of Child Health and Development to J.M.T. The authors do not have any conflicts of interest to declare. bioRxiv preprint doi: https://doi.org/10.1101/452342; this version posted October 29, 2018. -
Respiratory Adaptations to Lung Morphological Defects in Adult Mice Lacking Hoxa5 Gene Function
0031-3998/04/5604-0553 PEDIATRIC RESEARCH Vol. 56, No. 4, 2004 Copyright © 2004 International Pediatric Research Foundation, Inc. Printed in U.S.A. Respiratory Adaptations to Lung Morphological Defects in Adult Mice Lacking Hoxa5 Gene Function RICHARD KINKEAD, MICHELLE LEBLANC, ROUMIANA GULEMETOVA, MÉLANIE LALANCETTE-HÉBERT, MARGOT LEMIEUX, ISABEL MANDEVILLE, AND LUCIE JEANNOTTE Département de Pédiatrie [R.K., R.G.], Centre Hospitalier Universitaire de Québec, Centre de recherche de l’Hôpital St-François d’Assise, Québec, Canada, G1L 3L5, Centre de recherche en cancérologie de l’Université Laval [M.LeB., M.L.-H., M.Lem., I.M., L.J.], Centre Hospitalier Universitaire de Québec, L’Hôtel-Dieu de Québec, Québec, Canada, G1R 2J6 ABSTRACT The Hoxa5 mutation is associated with a high perinatal ventilation increase seen during hypoxia was similar for both mortality rate caused by a severe obstruction of the laryngotra- groups of mice; however, the dynamics of the frequency re- cheal airways, pulmonary dysmorphogenesis, and a decreased sponse was genotype-dependent. The hypercapnic ventilatory production of surfactant proteins. Surviving Hoxa5-/- mutant response did not differ between genotypes. These findings reveal mice also display lung anomalies with deficient alveolar septa- the strategies allowing survival of Hoxa5-/- mice facing morpho- tion and areas of collapsed tissue, thus demonstrating the impor- logic anomalies leading to a significant deficit in gas exchange tance of Hoxa5 throughout lung development and maturation. capacity. (Pediatr Res 56: 553–562, 2004) Here, we address the functional consequences of the Hoxa5 mutation on respiration and chemoreflexes by comparing the Abbreviations -/- breathing pattern of Hoxa5 mice to that of wild-type animals FICO2, fractional concentration of carbon dioxide in the under resting conditions and during exposure to moderate ven- inspired gas tilatory stimuli such as hypoxia and hypercapnia. -
Inactivation of HOXA Genes by Hypermethylation in Myeloid and Lymphoid Malignancy Is Frequent and Associated with Poor Prognosis Gordon Strathdee,1Tessa L
Imaging, Diagnosis, Prognosis Inactivation of HOXA Genes by Hypermethylation in Myeloid and Lymphoid Malignancy is Frequent and Associated with Poor Prognosis Gordon Strathdee,1Tessa L. Holyoake,2 Alyson Sim,1Anton Parker,4 David G. Oscier,4 Junia V. Melo, 5 Stefan Meyer,6,7 Tim Eden,7 Anne M. Dickinson,8 Joanne C. Mountford,2 Heather G. Jorgensen,2 Richard Soutar, 3 and Robert Brown1 Abstract Purpose: The HOX genes comprise a large family of homeodomain-containing transcription factors, present in four separate clusters, which are key regulators of embryonic development, hematopoietic differentiation, and leukemogenesis. We aimed to study the role of DNA methyl- ation as an inducer of HOX gene silencing in leukemia. Experimental Design: Three hundred and seventy-eight samples of myeloid and lymphoid leukemia were quantitatively analyzed (by COBRA analysis and pyrosequencing of bisulfite- modified DNA) for methylation of eight HOXA and HOXB cluster genes. The biological significance of the methylation identified was studied by expression analysis and through re-expression of HOXA5 in a chronic myeloid leukemia (CML) blast crisis cell line model. Results: Here, we identify frequent hypermethylation and gene inactivation of HOXA and HOXB cluster genes in leukemia. In particular, hypermethylation of HOXA4 and HOXA5 was frequently observed (26-79%) in all types of leukemias studied. HOXA6 hypermethylation was predomi- nantly restricted to lymphoid malignancies, whereas hypermethylation of other HOXA and HOXB genes was only observed in childhood leukemia. HOX gene methylation exhibited clear correla- tions with important clinical variables, most notably in CML, in which hypermethylation of both HOXA5 (P = 0.00002) and HOXA4 (P = 0.006) was strongly correlated with progression to blast crisis.