THE INFLUENCE OF SELENIUM, VITAMIN-E, AND ESTROGEN ON THE DEVELOPMENTOF TUMORS IN MICE EXPOSED TO SR-90

The primary object of this experiment was to evaluate the potential ro le of the antioxidants, selenium and vitamin E, in the anti-tumour def ence of mice internally irradiated with Sr-90. Comparison in terms of neoplastic response was made between mice kept on a selenium and viatm in E deficient diet and mice given the same deficient diet but adminis tered selenium and/or vitamin E in a controlled manner. The influence of simultaneous oestrogen treatment, known to promote radiogenic osteo sarcoma induction, was also investigated. Non-irradiated mice were use d as controls. Results are presented as crude and actuarial tumour inc idence. No significant difference in tumour yield or actuarial tumour incidence was found when the differently treated mouse groups were com pared, and accordingly no support was gained for the theory that the a ntioxidants selenium and vitamin E constitute a critical part of the c omplex defence system against neoplasms.