Carcinogenic Effect of Cholesterol in Mice. ∗

Summary

Mice of the T.M. strain maintained on a Rockland rat diet supplemented with cholesterol and lard develop a high incidence of mammary cancer and lung adenocarcinoma. In the absence of other lipids, cholesterol alone causes the development of a high incidence of lung adenocarcinoma. The incidence of mammary cancer in the mice of this group is very low, apparently due to the poor development of the ovaries and a low estrogen titer in the females receiving cholesterol. The appearance of giant basophile cells in the pituitary would be indicative of a low estrogen titer in these mice. The fact that cholesterol and lard cause the development of both mammary and lung cancer, while cholesterol alone causes almost exclusively the development of lung adenocarcinomas supports our point of view that there is a relationship between the nature of the malignancies in mice and the composition of the lipids in their diets.