The fact that apoptosis might influence the malignant phenotype has already been elucidated, and studies have revealed that a high frequency of apoptosis was observed in spontaneously-regressing tumors and in tumors treated with cytotoxic anticancer agents (37). A high index of apoptosis is a hallmark of important anti-tumorigenic activity. Therefore, many studies were performed in order to show the effect of carotenoids inducing programmed cell death (22, 27, 33, 38, 39, 40). In the present study, we showed that lycopene and beta-carotene induced programmed cell death. We observed similar characteristics to cell-cycle analysis, where lycopene