In many biologic systems, vitamin E and Se often act synergistically. Borek et al. (121) demonstrated that Se and RRR-a-tocopheryl succinate act alone by different mechanisms to prevent radiogenic and chemically induced transformation in vitro. They further showed that there was additive protection when both were used together (121).
Comparing and combining topical SeMet with oral d-a-tocopheryl acetate and topical d-a-tocopherol (122), the topical combination was less effective than topical vitamin E alone in prolonging the onset and in decreasing the incidence of UV-induced skin cancers in mice (122). Topical SeMet with oral vitamin E was more effective than either alone. In reducing UV-induced pigmentation, topical SeMet with topical or with oral vitamin E was more effective than any one antioxidant alone, particularly during the first eight weeks of UV exposure (122). Topical SeMet (alone or with vitamin E) prevented all blistering after initial UV exposure.