Every year more than 1 million new cases of ultraviolet radiation-induced non-melanoma skin cancers occur in the USA. Although exposure to sun and specifically ultraviolet radiation increases the risk of skin cancers, treatment of skin cancer cells with ultraviolet-B also results in their apoptosis, a favorable effect that seems to be stimulated by indole-3-carbinol. That is what scientist of the Seoul National University found in an experiment with cultured human melanoma cells . They investigated the effect of indole-3-carbinol on the sensitization to ultraviolet-B-induced apoptosis . They found that a combined treatment with the indole-3-carbinol and ultraviolet-B synergistically reduced melanoma cell viability, whereas the phytochemical or ultraviolet-B alone had little effect. Indole-3-carbinol acted by down-regulating pro-apoptotic protein Bcl-2.
Another study also demonstrated the protective action of indol-3-carbinol on ultraviolet-induced carcinogenic process on skin cells of mice . They conducted tests on groups of 20 mice exposed ultraviolet radiation and to fed with respectively chlorophyllin, indole-3-carbinol or placebo. The scientists found that rats fed with chlorophyllin should a significant increase in tumor multiplicity, whereas those supplemented with indol-3-carbinol has significant lower tumor multiplicity.
 Indole-3-carbinol enhances ultraviolet B-induced apoptosis by sensitizing human melanoma cells. Cell Mol Life Sci. 2006 Nov;63(22):2661-8.
 Ultraviolet radiation-induced non-melanoma skin cancer in the Crl:SKH1:hr-BR hairless mouse: augmentation of tumor multiplicity by chlorophyllin and protection by indole-3-carbinol. Photochem Photobiol Sci. 2006 May;5(5):499-507.