title: Mitochondrial genome alterations in rectal and sigmoid carcinomas.
abstract: The scarce studies on the molecular pathways involved in the pathogenesis of rectal cancer indicate that these may vary, at least in part, from those relevant for colon cancer. Mitochondrial DNA alterations have been described in several human cancers. We aimed to study D310, ND1 and ND5 microsatellite sequence alterations and nuclear microsatellite instability in a series of 38 rectal carcinomas as compared to a series of 25 sigmoid carcinomas. D310 sequence alterations were observed in 34.3% and 37.5% of rectal and sigmoid carcinomas, respectively, whereas ND1 mutations were present in 2.6% in RC and ND5 mutations were detected in 5.3% and 8% of rectal and sigmoid carcinomas, respectively. A trend toward an association between nuclear and mitochondrial microsatellite instability was observed in sigmoid but not in rectal cancers. In conclusion, mitochondrial genome alterations are common in both rectal and sigmoid carcinomas and may contribute to their pathogenesis.
authors.affiliation: Department of Genetics, Portuguese Oncology Institute, Porto, Portugal.
authors.forename: Manuela
authors.initials: M
authors.lastname: Pinheiro
authors.forename: Isabel
authors.initials: I
authors.lastname: Veiga
authors.forename: Carla
authors.initials: C
authors.lastname: Pinto
authors.forename: Luís
authors.initials: L
authors.lastname: Afonso
authors.forename: Olga
authors.initials: O
authors.lastname: Sousa
authors.forename: Maria
authors.initials: M
authors.lastname: Fragoso
authors.forename: Lúcio
authors.initials: L
authors.lastname: Santos
authors.forename: Paula
authors.initials: P
authors.lastname: Lopes
authors.forename: Irene
authors.initials: I
authors.lastname: Pais
authors.forename: Carlos
authors.initials: C
authors.lastname: Lopes
authors.forename: Manuel R
authors.initials: MR
authors.lastname: Teixeira
mesh_terms: D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000235:genetics* / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D004252:DNA Mutational Analysis; D004272:DNA, Mitochondrial; D005260:Female; D015894:Genome, Human; D006801:Humans; D008297:Male; D018895:Microsatellite Repeats; D008875:Middle Aged; D009154:Mutation; D012004:Rectal Neoplasms / Q000235:genetics* / Q000378:metabolism*; D012811:Sigmoid Neoplasms / Q000235:genetics* / Q000378:metabolism*
chemical_list: D004272:DNA, Mitochondrial