Asbestos and benzo(a)pyrene act synergistically to induce squamous metaplasia and incorporation of (/sup 3/H)thymidine in hamster tracheal epithelium
When exposed to either crocidolite asbestos (single 1-h exposure to 0.4 mg/ml medium) or the polycyclic aromatic hydrocarbon, benzo(a)pyrene (BaP) (less than or equal to 2.5 micrograms/ml medium, 1x weekly for 4 weeks), the epithelium of hamster tracheal explants exhibits insignificant amounts of squamous metaplasia, an atypical lesion, in comparison to amounts observed in untreated tissues. Incorporation of (/sup 3/H)thymidine, an indication of DNA synthesis by epithelial cells, likewise is unchanged. However, the extent of squamous metaplasia and numbers of labeled basal and suprabasal cells are increased substantially when BaP and asbestos are added in combination. These results suggest an important mechanism of co-carcinogenesis involving chemical and physical carcinogens and support epidemiologic observations documenting an increased risk of bronchogenic carcinoma in asbestos workers who smoke.
- Research Organization:
- Univ. of Vermont Coll. of Medicine, Burlington
- OSTI ID:
- 5948422
- Journal Information:
- Carcinogenesis (N.Y.); (United States), Journal Name: Carcinogenesis (N.Y.); (United States) Vol. 5:11; ISSN CRNGD
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
560305* -- Chemicals Metabolism & Toxicology-- Vertebrates-- (-1987)
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMAL TISSUES
ANIMALS
AROMATICS
ASBESTOS
AZINES
BENZOPYRENE
BIOLOGICAL MODELS
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
BODY
CARCINOGENESIS
CONDENSED AROMATICS
DISEASES
DNA REPAIR
EPITHELIOMAS
EPITHELIUM
HAMSTERS
HETEROCYCLIC COMPOUNDS
HYDROCARBONS
IN VITRO
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
MAMMALS
NEOPLASMS
NUCLEOSIDES
NUCLEOTIDES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PATHOGENESIS
PYRIMIDINES
RECOVERY
REPAIR
RESPIRATORY SYSTEM
RIBOSIDES
RODENTS
SYNERGISM
THYMIDINE
TISSUES
TRACER TECHNIQUES
TRACHEA
TRITIUM COMPOUNDS
VERTEBRATES