title: Pharmacoepigenetics in gastrointestinal tumors: MGMT methylation and beyond.
abstract: Epigenetic mechanisms are involved in gastrointestinal (GI) cancer pathogenesis. Insights into the molecular basis of GI carcinogenesis led to the identification of different epigenetic pathways and signatures that may play a role as therapeutic targets in metastatic colorectal cancer (mCRC) and non-colorectal GI tumors. Among these alterations, O6-methylguanine DNA methyltransferase (MGMT) gene promoter methylation is the most investigated biomarker and seems to be an early and frequent event, at least in CRC. Loss of expression of MGMT as a result of gene promoter methylation has been associated with interesting activity of alkylating agents in mCRC. However, the optimal methods for the definition of the MGMT status and additional predictive factors beyond MGMT in GI malignancies are lacking. Here we review the current role of MGMT methylation and other epigenetic alterations as potential treatment targets in GI tumors.
authors.affiliation: Unit of Medical Oncology 2, Azienda Ospedaliero-Universitaria Pisana, Istituto Toscano Tumori, Via Roma 67, 56126 Pisa, Italy, lorenzo.fornaro@gmail.com.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Fornaro
authors.affiliation: Unit of Medical Oncology 2, Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy, 2Unit of Oncology, Department of Oncology, Azienda USL2, Lucca, Italy.
authors.forename: Caterina
authors.initials: C
authors.lastname: Vivaldi
authors.affiliation: Unit of Medical Oncology 2, Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Caparello
authors.affiliation: Unit of Medical Oncology 2, Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy.
authors.forename: Gianna
authors.initials: G
authors.lastname: Musettini
authors.affiliation: Unit of Medical Oncology 2, Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy.
authors.forename: Editta
authors.initials: E
authors.lastname: Baldini
authors.affiliation: Unit of Medical Oncology 2, Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Masi
authors.affiliation: Unit of Medical Oncology 2, Azienda Ospedaliero-Universitaria Pisana, Pisa, Italy.
authors.forename: Alfredo
authors.initials: A
authors.lastname: Falcone
mesh_terms: D019175:DNA Methylation; D015254:DNA Modification Methylases / Q000235:genetics*; D045643:DNA Repair Enzymes / Q000235:genetics*; D044127:Epigenesis, Genetic; D005770:Gastrointestinal Neoplasms / Q000235:genetics*; D006801:Humans; D010597:Pharmacogenetics; D025521:Tumor Suppressor Proteins / Q000235:genetics*
chemical_list: D025521:Tumor Suppressor Proteins; D015254:DNA Modification Methylases; C515491:MGMT protein, human; D045643:DNA Repair Enzymes