Immunohistochemical detection of pulmonary cytochrome P450IA and metabolic activities associated with P450IA1 and P450IA2 isozymes in lung cancer patients.
Environ Health Perspect
; 98: 179-82, 1992 Nov.
Article
em En
| MEDLINE
| ID: mdl-1336724
ABSTRACT
The main polycyclic aromatic hydrocarbon-inducible cytochrome P450 was studied in lung tissue from 57 lung cancer patients by immunohistochemistry, using a monoclonal antibody (1-7-1) that recognizes P450IA1 and P450IA2 isozymes. The intensity of immunostaining was compared with the pulmonary activity of a P450IA1-dependent enzyme, aryl hydrocarbon hydroxylase (AHH), and with P450IA2-related metabolic activity estimated from the ratio of caffeine metabolites in urine. Immunostaining was not observed in peripheral lung tissue of nonsmokers or ex-smokers but was seen in the bronchiolar and alveolar epithelium of all patients who were smokers and had a peripheral carcinoma (16/16) and of 60% (10/17) of those who had a bronchial carcinoma. AHH activity was positively related to the intensity of immunostaining, and an almost 2-fold increase due to smoking was detected in the ratios of caffeine metabolites. These results demonstrate that tobacco smoke induces P450IA1 in the lung and probably P450IA2 in the liver, and suggest a role for certain metabolic phenotypes of P450IA1 in peripheral pulmonary carcinoma.
Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Oxirredutases
/
Hidrocarboneto de Aril Hidroxilases
/
Fumar
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Sistema Enzimático do Citocromo P-450
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Neoplasias Pulmonares
Tipo de estudo:
Diagnostic_studies
/
Risk_factors_studies
Limite:
Adult
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Aged
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Environ Health Perspect
Ano de publicação:
1992
Tipo de documento:
Article
País de afiliação:
Finlândia