title: Alterations of tumor suppressor genes and the H-ras oncogene in oral squamous cell carcinoma.
abstract: The frequencies of mutations in the adenomatous polyposis coli (APC). p53, and p16 (MTS1; multiple tumor suppressor 1/CDK4I; cyclin-dependent kinase 4 inhibitor) tumor suppressor genes were investigated in 23 oral squamous cell carcinomas (SCCs). Loss of heterozygosity (LOH) at the retinoblastoma (Rb) gene locus and on chromosomes 3p (VHL; von Hippel-Lindau disease tumor suppressor gene locus), 5q (APC) and 9p (p16), and H-ras oncogene mutations were also studied in the same samples. Techniques employed were polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP), DNA sequencing and PCR-microsatellite analyses. Mutations of the p53 gene were detected in 26% (6/23) of the tumor specimens. APC and p16 were not mutated in any of the 23 oral SCCs studied. LOH was detected in 17% (2/12 informative cases) at the Rb, in 33% (4/12) on 3p, in 17% (4/ 23) on 5q and in 30% (3/10) on 9p. Mutations of the H-ras gene were detected in 9% (2/23). The only correlation between these genetic alterations and clinicopathologic characteristics was that mutations of the p53 gene were detected more frequently in oral SCCs with lymph node metastasis than in those without it (P < 0.05). These results demonstrate that mutations of the p53 gene and LOH on 3p and 9p frequently occur in oral SCC and play important roles in the development and/or progression of this common malignancy.
authors.affiliation: Second Department of Oral and Maxillofacial Surgery, Iwate Medical University School of Dentistry, Morioka, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Sakata
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000235:genetics*; D002893:Chromosomes, Human, Pair 3; D002899:Chromosomes, Human, Pair 9; D004252:DNA Mutational Analysis; D004273:DNA, Neoplasm / Q000235:genetics; D005260:Female; D017353:Gene Deletion; D015972:Gene Expression Regulation, Neoplastic; D016147:Genes, Tumor Suppressor / Q000235:genetics*; D016158:Genes, p53 / Q000235:genetics; D011905:Genes, ras / Q000235:genetics*; D006801:Humans; D008297:Male; D018895:Microsatellite Repeats; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000235:genetics*; D009154:Mutation; D016133:Polymerase Chain Reaction; D018807:Polymorphism, Single-Stranded Conformational
chemical_list: D004273:DNA, Neoplasm