Ohio State University Research Foundation, Columbus, Ohio, Final Report 1978 Jan:33 pages
To help resolve the conflicting reports concerning the effects of heat on tumorigenesis, an experiment was performed to produce skin carcinoma by repeated topical application of benzo(a)pyrene (50328) (BaP) in mice kept at two ambient temperatures, 23 or 30 degrees-C. The animals were monitored continuously until death, whether natural or by sacrifice. The animals were C3H male mice, 9 weeks old at the time treatment commenced. Four treatment groups were established: 1) no treatment controls; 2) BaP vehicle only, toluene (108883); 3) high level carcinogen, 2.0mg BaP/wk; and (4) low level carcinogen, behavior, presence of inflammation, keratinization, and/or neoplastic lesions. Bodyweights were taken every other week. Tumors were evaluated in terms of size, ulceration (whether single or multiple), and metastasis. Absolute bodyweights remained approximately the same in all mice in the experimental groups. However, there was a difference in true bodyweights and tumor weights between the control animals and those in warm environments. True bodyweights were consistently about 2 grams less in high dose BaP mice in those in the warm environment. The same held true for the low BaP mice, the true bodyweight running approximately 3 grams less in the warm room. Liver weights were consistently 200mg heavier in high and low BaP mice in the control environment. It is suggested that greater resistance to tumors shown by mice in the warm room may be reflected by larger tumor size. No differences could be found between squamous cell carcinoma development in control or warm environments.
Ohio State University Research Foundation, Columbus, Ohio, Final Report