The role of lycopene and its derivatives in the regulation of transcription systems: implications for cancer prevention

Abstract

Evidence from epidemiologic studies has suggested that carotenoids, and lycopene in particular, decrease the risk of cancer: however, not all studies support this view. To gain insight into the molecular mechanisms whereby lycopene and other carotenoids may exert their chemoprotective effects, we and others performed a series of studies that used a large panel of cancer cell lines of different lineages and animal models of human cancer. In this review we address some of the mechanisms proposed for the cancer-preventive activity of tomato lycopene, focusing on the induction of the antioxidant response element transcription system and the inhibition of the transcriptional activity of sex hormones, such as estrogens and androgens, and the activity of growth factors, such as insulin-like growth factor. We also considered the modulation by lycopene of the transcription factors peroxisome proliferator-activated receptor, retinoid X receptor, liver X receptor, and activating protein-1. The ligands and the phytonutrient regulators of these transcription systems contain electrophilic active groups, whereas lycopene and nonxanthophylic carotenoids are devoid of them. Thus, we suggest that at least some of the cellular effects of carotenoids are mediated through their derivatives formed either by chemical oxidation or by enzymatic cleavage inside the cells. This review highlights findings that pertain to this exciting avenue of research, which is currently under intense scrutiny in several laboratories worldwide.

Carotenoid derivatives inhibit nuclear factor kappa B activity in bone and cancer cells by targeting key thiol groups

“…This question is pertinent not only with respect to the NFkB system but also to several additional cellular processes found to be modulated by oxidized carotenoid derivatives [42,73]. As noted in the Introduction, in vitro oxidation of carotenoids leads to the formation of mono and dialdehyde products called apocarotenals and diapocarotene-dials, respectively [41].…”

Dietary Tomato and Lycopene Impact Androgen Signaling- and Carcinogenesis-Related Gene Expression during Early TRAMP Prostate Carcinogenesis

“…Laboratory studies provide evidence that tomato and lycopene may suppress oxidative damage, modulate intracellular signaling resulting in reduced proliferation, and enhance sensitivity to apoptosis, among other mechanisms (6). Some evidence suggests that tomato or lycopene intake may modulate testosterone production, serum concentrations, and metabolism, and may impact gene expression in human prostate cancer cells, normal rat prostate, and established prostate cancer xenografts (7-10). However, whether lycopene and/or other tomato phytochemicals inhibit prostate cancer by targeting androgen signaling and metabolism in early stages of prostate carcinogenesis has not been thoroughly investigated.…”

Paprika and/or marigold extracts in diets for laying hens

“…The capsaicinoids in the paprika extract have antioxidant effects (COSTA et al, 2010) and reduces the plasmatic cholesterol levels and the formation of atheromatous plaque in human being (HUANG et al, 2014). Several reports revised the safety of lutein for adults (JECFA, 2006;SHAO & HATHCOCK, 2006). A study concluded that 200 mcg/L lutein in formulations for babies is safe (EFSA, 2008).…”