title: DNA methylation and cancer pathways in gastrointestinal tumors.
abstract: Cancer is fundamentally a genetic and epigenetic disease that requires the accumulation of genomic alterations that inactivate tumor suppressors and activate proto-oncogenes. In addition to genetic mutation or allelic loss, epigenetic gene silencing associated with DNA methylation is now recognized as an alternative mechanism by which tumor suppressor genes are inactivated. In gastrointestinal cancers, for example, DNA methylation frequently alters the activity in a number of important signaling pathways by silencing expression of genes encoding Wnt antagonists, negative Ras effectors and p53 targets. Indeed, the list of genes aberrantly methylated in cancer is growing, and methylation of a p53 target micoRNA gene has recently been demonstrated. Sites of DNA methylation could be promising markers and targets for risk assessment, early detection and treatment of cancer.
authors.affiliation: First department of Internal Medicine, Sapporo Medical University, Japan.
authors.forename: Hiromu
authors.initials: H
authors.lastname: Suzuki
authors.forename: Takashi
authors.initials: T
authors.lastname: Tokino
authors.forename: Yasuhisa
authors.initials: Y
authors.lastname: Shinomura
authors.forename: Kohzoh
authors.initials: K
authors.lastname: Imai
authors.forename: Minoru
authors.initials: M
authors.lastname: Toyota
mesh_terms: D019175:DNA Methylation; D005770:Gastrointestinal Neoplasms / Q000235:genetics*; D020868:Gene Silencing; D006801:Humans; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism; D051153:Wnt Proteins / Q000235:genetics / Q000378:metabolism; D018631:ras Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D016159:Tumor Suppressor Protein p53; D051153:Wnt Proteins; D018631:ras Proteins