RESUMEN
Activating mutation in K-ras gene is a key event in the pathogenesis of colon carcinoma. This study analyses frequency of this mutation in different age groups of colorectal cancer patients residing in North-Western Russia, and examines its relationship with essential clinical characteristics of tumor disease.
Asunto(s)
Envejecimiento/genética , Neoplasias del Colon/genética , Genes ras/genética , Mutación , Neoplasias del Recto/genética , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento/patología , Neoplasias del Colon/epidemiología , Neoplasias del Colon/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tasa de Mutación , Reacción en Cadena de la Polimerasa , Neoplasias del Recto/epidemiología , Neoplasias del Recto/patología , Federación de RusiaRESUMEN
The genetic polymorphism of metabolizers of tobacco smoke carcinogens can influence individual susceptibility to lung cancer. The study was concerned with the Mspl-polymorphism of the CYP1A1 gene responsible for encoding aryl hydrocarbon hydroxylase. It also plays a role in the activation of polycyclic aromatic hydrocarbons (PAH). The CYP1A1 alleles and genotype distribution in 146 lung cancer patients was compared with that in 230 healthy donors. Another control group consisted of 259 "cancer-resistant" subjects, i.e. tumor-free smokers and non-smokers aged 75 and more. The CYP1A1 allele incidence (19%) in patients with squamous lung cancer was significantly higher than in the control cohorts (11%) which is consistent with the leading role of PAH in the etiology of this pathology.
Asunto(s)
Hidrocarburo de Aril Hidroxilasas/genética , Citocromo P-450 CYP1A1/genética , Frecuencia de los Genes , Neoplasias Pulmonares/genética , Proteínas de la Membrana/genética , Polimorfismo Genético , Serina Endopeptidasas/genética , Donantes de Tejidos , Adulto , Anciano , Hidrocarburo de Aril Hidroxilasas/metabolismo , Estudios de Casos y Controles , Activación Enzimática/genética , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Neoplasias Pulmonares/enzimología , Masculino , Persona de Mediana Edad , Fumar/efectos adversosRESUMEN
L-MYC and GSTMI polymorphisms were studied in glioma patients. L-MYC allele frequency in patients (L: 61/114 (54%); S: 53/114 (46%)) and controls (L: 108/204 (53%); S: 96/204 (47%)) was identical. S allele was associated with certain unfavourable clinical features of the disease. In particular, its frequency was 26/42 (62%) in relapse vs. 26/68 (38%) in relapse-free disease (p < 0.05). GSTMI "null" genotype was identified in both patients and healthy donors (48%). GSTMI-deficient genotypes were significantly predominant in patients with grade III-IV gliomas as compared with grade I-II tumors (p < 0.05). Patients, but not donors, frequently revealed a combination of SS L-MYC homozygosity and GSTMI (-) variant (p < 0.01) as well as an association of LL L0-MYC homozygosity and GSTMI (+) genotype (p < 0.05).
Asunto(s)
Neoplasias Encefálicas/genética , Genes myc/genética , Glioma/genética , Glutatión Transferasa/genética , Polimorfismo Genético , Alelos , Neoplasias Encefálicas/enzimología , Estudios de Casos y Controles , Supervivencia sin Enfermedad , Genotipo , Glioma/enzimología , Homocigoto , HumanosRESUMEN
By the restriction analysis method we established that methylation of the 5'-end cytosine in 5'-m5CC-3' duplexes had individual specific features. This genetic peculiarity did not change even in DNA from human stomach carcinomas.
Asunto(s)
Citosina/análogos & derivados , ADN/genética , Variación Genética , Citosina/metabolismo , ADN/metabolismo , Sondas de ADN , Genes ras , Humanos , Neoplasias Gástricas/genética , Úlcera Gástrica/genéticaRESUMEN
A method of the restriction analysis by Msp I enzyme has been used to analyze the 12th codon of Ha-ras-1 protooncogene in 10 human carcinomas and in the stomach mucosa adjacent to them their 5 metastases into the regional lymph nodes and in 2 ulcers. No point mutation was found.
Asunto(s)
Adenocarcinoma/genética , Codón/genética , Genes ras/genética , Proto-Oncogenes/genética , ARN Mensajero/genética , Úlcera Gástrica/genética , ADN/genética , ADN de Neoplasias/genética , Humanos , Metástasis Linfática , Biología Molecular , Mutación , Proto-Oncogenes MasRESUMEN
Ha-ras restriction fragments' length polymorphism (RFLP) in white blood cells and stomach tissues from patients with carcinoma and ulcer of the stomach was examined. Genomic DNAs were digested with Xho I, Pvu II, Pst I, Msp I, Bcn I, Mva I, Bsp RI. No Ha-ras-1 polymorphic variants specifically associated with the cancer disease were detected. RFLP of the 3'-noncoding sequence of c-Ha-ras-1 gene had got features of the definite human population. The cells forming the tissue were examined and individual peculiarity of the methylated residues disposition seemed to influence RFLP of the 5'-noncoding sequence of c-Ha-ras-1.