title: Gene body methylation can alter gene expression and is a therapeutic target in cancer.
abstract: DNA methylation in promoters is well known to silence genes and is the presumed therapeutic target of methylation inhibitors. Gene body methylation is positively correlated with expression, yet its function is unknown. We show that 5-aza-2'-deoxycytidine treatment not only reactivates genes but decreases the overexpression of genes, many of which are involved in metabolic processes regulated by c-MYC. Downregulation is caused by DNA demethylation of the gene bodies and restoration of high levels of expression requires remethylation by DNMT3B. Gene body methylation may, therefore, be an unexpected therapeutic target for DNA methylation inhibitors, resulting in the normalization of gene overexpression induced during carcinogenesis. Our results provide direct evidence for a causal relationship between gene body methylation and transcription.
authors.affiliation: Department of Urology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA.
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Yang
authors.affiliation: Department of Urology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA.
authors.forename: Han
authors.initials: H
authors.lastname: Han
authors.affiliation: The Princess Margaret Cancer Centre, University Health Network, Toronto ON M5G 1L7, Canada; Department of Medical Biophysics, University of Toronto, Toronto ON M5G 2M9, Canada.
authors.forename: Daniel D
authors.initials: DD
authors.lastname: De Carvalho
authors.affiliation: Department of Urology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA.
authors.forename: Fides D
authors.initials: FD
authors.lastname: Lay
authors.affiliation: Department of Urology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA. Electronic address: pjones@med.usc.edu.
authors.forename: Peter A
authors.initials: PA
authors.lastname: Jones
authors.affiliation: Department of Urology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA. Electronic address: gliang@usc.edu.
authors.forename: Gangning
authors.initials: G
authors.lastname: Liang
mesh_terms: D002455:Cell Division; D003110:Colonic Neoplasms / Q000235:genetics / Q000473:pathology; D019175:DNA Methylation; D015870:Gene Expression; D006801:Humans; D011401:Promoter Regions, Genetic