RESUMO
A single-nucleotide polymorphism in the MDM2 promoter (SNP309; rs2279744) causes elevated transcription of this major negative regulator of p53 in several cancer types. We investigated MDM2 SNP309 and CDKN1A (p21/Waf1/Cip1) codon 31 (rs1801270) polymorphisms in 86 cases of cutaneous Kaposi's sarcoma (KS) from African and Caucasian patients, and 210 healthy controls. A significant increase of the MDM2 SNP309 T/G genotype was observed among classic KS cases (odds ratio 2.38, 95% confidence interval 1.0-5.5). Frequencies of CDKN1A codon 31 genotypes were not significantly different between cases and controls. The results suggest that the MDM2 SNP309 G allele may act as a susceptibility gene for the development of classic KS in Caucasian patients.
Assuntos
População Negra/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Polimorfismo de Nucleotídeo Único/genética , Proteínas Proto-Oncogênicas c-mdm2/genética , Sarcoma de Kaposi/genética , População Branca/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Frequência do Gene/genética , Predisposição Genética para Doença/genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Sarcoma de Kaposi/diagnóstico , Proteína Supressora de Tumor p53/genética , Adulto JovemRESUMO
OBJECTIVES: Several studies have examined the association of codon 72 polymorphism of the TP53 gene, encoding either arginine or proline, in several tumor types but none have investigated its role in Kaposi's sarcoma (KS) development. METHODS: In this prevalent case-control study, 67 cutaneous lesions of classic, iatrogenic, endemic as well as epidemic KS from African (n = 22) and Caucasian (n = 45) patients, and blood samples from 150 healthy controls (n = 57 African, n = 93 Caucasian) have been analyzed for arginine and proline allele distribution. RESULTS: Among African cases the proline homozygous, heterozygous and arginine homozygous genotype frequencies were 50.0, 31.8 and 18.2%, respectively, and among controls 54.4, 40.3, and 5.3%, respectively (p = 0.1872). Conversely, among Caucasian cases genotype distributions were 6.7, 55.6, and 37.8%, and among controls 7.5, 34.4, and 58.1%, respectively (p = 0.0567). No significant differences in arginine and proline allele distribution were observed when the cases were stratified by HIV status/tumor type. CONCLUSIONS: The results obtained in this study suggest that p53 polymorphism at codon 72 does not represent a risk factor for the development of all forms of KS, either among African or among Caucasian populations.