title: Genetic instability, p53 and nm23 mutation and clinicopathological features in rectal carcinoma.
abstract: Defective DNA mismatch repair proteins fail to correct replication errors (RERs). These defects may lead to secondary, mutation of oncogenes and tumor suppressor genes. Microsatellite instability might be a marker of such replication errors. Eighteen rectal tumors were examined to evaluate genetic instability, in sporadic rectal cancer by PCR. RERs were observed in 27.8% of the cases. No significant difference was noticed between RER+ and RER- patients as far as prognosis, clinicopathological features and p53 gene mutation are concerned. The incidence of nm23 gene mutation was the only statistically significant difference between the 2 groups. Three patients with only one altered microsatellite showed advanced tumor and nm23 gene mutation. Two cases with 5 altered microsatellites and nm23 gene mutated are disease-free: in one of them the p53 gene was also mutated. Probably more than one altered microsatellite is necessary to protect from the effects of secondary mutations.
authors.affiliation: First Department of Surgery, University of Rome La Sapienza, Rome, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Indinnimeo
authors.forename: C
authors.initials: C
authors.lastname: Cicchini
authors.forename: A
authors.initials: A
authors.lastname: Stazi
authors.forename: P
authors.initials: P
authors.lastname: Mingazzini
authors.forename: M A
authors.initials: MA
authors.lastname: Caligo
authors.forename: C
authors.initials: C
authors.lastname: Ghimenti
authors.forename: G
authors.initials: G
authors.lastname: Bevilacqua
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D016158:Genes, p53; D006801:Humans; D008297:Male; D018895:Microsatellite Repeats; D008875:Middle Aged; D020559:Monomeric GTP-Binding Proteins; D009154:Mutation; D054778:NM23 Nucleoside Diphosphate Kinases; D009701:Nucleoside-Diphosphate Kinase; D016133:Polymerase Chain Reaction; D012004:Rectal Neoplasms / Q000235:genetics* / Q000473:pathology; D014157:Transcription Factors / Q000235:genetics*
chemical_list: D054778:NM23 Nucleoside Diphosphate Kinases; D014157:Transcription Factors; C517938:NME1 protein, human; D009701:Nucleoside-Diphosphate Kinase; D020559:Monomeric GTP-Binding Proteins