Vitamin E inhibits experimental carcinogenesis and tumour angiogenesis

In an experiment in which vitamin E inhibited carcinogenesis, it was found that tumour angiogenesis and tumour growth-factor alpha (TGF alpha) expression were also inhibited. Forty male golden hamsters were divided into four equal groups. Group 1 animals had the left buccal pouches painted three times weekly with 7,12-dimethylbenz(a)anthracene (DMBA) for 14 weeks. Group 2 animals had the same procedure of DMBA applications but also received alpha tocopherol. Groups 3 and 4 were vitamin E and untreated controls. Angiogenesis was studied with factor 8-related antigen (F8-RA) which identifies endothelial cells. TGF alpha was studied with the appropriate antibody. Staining was effected by the standard avidin-biotin horseradish peroxidase system. Mean tumour volume was significantly lower in the DMBA-vitamin E group compared to the tumour control group. Angiogenesis was significantly inhibited in the DMBA-vitamin E group and TGF alpha expression was also inhibited. It is suggested that inhibition of tumour angiogenesis by vitamin E may be an additional mechanism for the anticancer action of vitamin E.