Publication | Closed Access
Induction of Lung Cancer in Germfree, Specific-Pathogen-Free, and Infected Rats by <italic>N</italic>-Nitrosoheptamethyleneimine: Enhancement by Respiratory Infection<xref ref-type="fn" rid="FN2">2</xref>
66
Citations
0
References
1972
Year
Acute Lung InjuryChronic Murine PneumoniaInflammatory Lung DiseaseLung InflammationImmunologyPathologyTumor BiologyDrinking WaterOncologyRespiratory ToxicologyCancer Cell BiologyRespiratory InfectionPulmonary PharmacologyRadiation OncologyCancer ResearchOncogenic AgentLung CancerInhalation ToxicologyInfected RatsPathogenesisBronchial NeoplasmMedicine
The effect of chronic respiratory infection on the development of lung cancer induced by N-nitrosoheptamethyleneimine was tested in rats. The nitrosamine was administered in drinking water for 22 weeks to germfree and specific-pathogen-free (SPF) rats and to rats with chronic murine pneumonia. All animals were killed 2 weeks after the last treatment. The incidence of lung neoplasms was 17% in germfree males, 37% in SPF males, and 83% in infected males. An incidence of 90–100% was found among females in all 3 experimental groups. The results in males demonstrate that chronic respiratory infection can enhance the neoplastic response of the lungs to a systemic carcinogen. The normal microbial flora does not seem to be essential for tumor induction by this nitrosamine. There was no significant difference in incidence of esophageal tumors among the 3 groups.—J Natl Cancer Inst 49: 1107–1114, 1972.