Beta-carotene in prevention of cutaneous carcinogenesis.

Beta-carotene, administered orally to mice, caused a decrease in angiogenesis evoked by HPV-transformed tumorigenic cell lines (SKv-t, HeLa). It did not affect angiogenesis induced by the non-tumorigenic SKv (not-t) cell line, and increased lymphocyte-induced immune angiogenesis. We suggest that the anti-cancerogenic effect of beta-carotene may be due, at least in part, to its inhibitory effect on formation of new blood vessels within the tumour mass.