Suppression of X-ray induced transformation by vitamin E in mouse C3H/10T1/2 cells.

Vitamin E (d-alpha-tocopherol) was shown to decrease X-ray induced transformation in mouse C3H/10T1/2 cells. The d-alpha-tocopherol was active in the form of succinate diluted in ethanol, but was inactive at the highest nontoxic concentration of the pure substance dissolved in oil and diluted in acetone. Vitamin E succinate was effective when present throughout the entire assay period or when treatments began after confluence was reached at day 12 post-irradiation. It was ineffective if present only for the early portion of the radiation transformation assay period, indicating that its effect may be reversible. Vitamin E did not suppress the growth and expression of transformed C3H/10T1/2 cells as foci when the transformed cells were surrounded by a monolayer of normal cells.