RESUMEN
G2 chromosomal sensitivity to bleomycin (30 micrograms/ml) was tested in PHA-stimulated lymphocytes of healthy subjects and in patients with familial and sporadic tumors. These were multiple endocrine neoplasias (MEN) types 1, 2A and 2B, familial medullar thyroid cancer, Recklinghausen neurofibromatosis type I, sporadic and hereditary malignant tumors, and a preleukemic disorder, the myelodysplastic syndrome. Control subjects were either young (15-20), middle-aged (28-49) or old (70-83 years). Cells from old healthy subjects and from subjects with MEN 1 showed increased sensitivity to clastogenic effects of bleomycin. All the remaining investigated groups were insignificantly different from controls. Our data suggest that in contrast with recessively inherited syndromes with chromosome instability the mutagen hypersensitivity, as evaluated by the extent of chromosomal damage, is not a feature of most dominantly inherited tumor syndromes.
Asunto(s)
Bleomicina/farmacología , Aberraciones Cromosómicas , Genes Dominantes , Síndromes Neoplásicos Hereditarios/genética , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Células Cultivadas , Niño , Cromátides/efectos de los fármacos , Daño del ADN , Fase G2 , Humanos , Persona de Mediana Edad , Neoplasia Endocrina Múltiple/genética , Síndromes Mielodisplásicos/genética , Neurofibromatosis 1/genética , Neoplasias de la Tiroides/genéticaRESUMEN
Phytohemagglutinin-stimulated lymphocytes from 20 young (16-28 years) and 20 old (70-88 years) healthy subjects have been investigated for chromosome aberrations before and after exposure to bleomycin in G2 phase of the cell cycle. No differences were found in unexposed cultures between young and old donors. After treatment with bleomycin the frequency of chromosome aberrations was significantly higher in the old subjects than in the young ones (p less than 0.05). The results suggest that the different interaction between the mutagen and DNA may be caused by the decreased capacity of the excision repair system in the cells of the old individuals.
Asunto(s)
Envejecimiento/genética , Bleomicina/efectos adversos , Aberraciones Cromosómicas , Linfocitos/efectos de los fármacos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Reparación del ADN/efectos de los fármacos , Femenino , Humanos , Linfocitos/ultraestructura , Masculino , Persona de Mediana Edad , Mitosis/efectos de los fármacosRESUMEN
Phytohaemagglutinin-stimulated lymphocytes from 20 young (16-28 years) and 20 old (70-88 years) healthy subjects were examined for chromosome aberrations before and after exposure to bleomycin in the G2 phase of the cell cycle. No differences were found in unexposed cultures between young and old donors. After treatment with bleomycin, the rate of chromosome aberrations was significantly higher in the elderly persons (p less than 0.05). As the results suggest, different interaction between the mutagen and DNA may be caused by the decreased capacity of the excision repair system in the elderly individuals cells.