Lycopene cancers

Bowen, P, L. Chen, M. Stacewicz-Sapuntzakis et al. 2002. Tomato sauce supplementation and prostate cancer Lycopene accumulation and modulation of biomarkers of carcinogenesis. Exp Biol Med (Maywood) 227(10) 886-893. 

Cancer lycopene molecular mechanism nutrition prevention... 

In this chapter, we have summarized the potential effects of lycopene in prevention and treatment of cancer. Lycopene intake and plasma levels of lycopene have been inversely associated with cancer risk in most of the case-control studies and animal studies. Clinical trials need to be craiducted to investigate lycopene in prevention of cancer and as an adjunct to standard cancer therapy. Until more data is available regarding lycopene supplementation, it is suggested that the potential health benefits of lycopene can best be achieved through a diet rich in a variety of fruits and vegetables, which include tomatoes. 

GiovANNUcci E (1999) Tomatoes, tomato-based products, lycopene, and cancer review of the epidemiologic literature , J Natl Cancer Inst, 99, 317-31. 

KHACHIK F, BEECHER G R and SMITH J c (1995) Lutein, lycopene, and their oxidative metabolites in chemoprevention of cancer , J Cell Biochem Supp, 22, 236-46. 

An evaluation of the Health Professionals Follow-Up Study (Giovannucci et al., 1995) has detected a lower prostate cancer risk associated with the greater consumption of tomatoes and related food products. Tomatoes are the primary dietary source of lycopene and lycopene concentrations are highest in testis and adrenal tissue (Clinton, 1998). In paired benign and malignant prostate tissue from 25 American men, 53-74 yrs, undergoing... 

J w, Jr. (1996) Cis-trans lycopene isomers, carotenoids and retinol in the human prostate. Cancer Epidemiol Biomarkers Prev. 5(10) 823-33. 

GANN P H, GIOVANNUCCI E, WILLETT W, SACHS F H, HENNEKENS C H and STAMPFER M I (1999) Lower prostate cancer risk in men with elevated plasma lycopene levels results of a prospective analysis , Cancer Res, 59, 1225-30. 

GIOVANNUCCI E, RIMM E B, LIU Y, STAMPFER M J and WILLETT w c (2002) A prospective study of tomato products, lycopene and prostate cancer risk , J Natl Cancer Inst, 94, 391-8. 

Carotenoids and prostate cancer — Numerous epidemiological studies including prospective cohort and case-control studies have demonstrated the protective roles of lycopene, tomatoes, and tomato-derived products on prostate cancer risk other carotenoids showed no effects. " In two studies based on correlations between plasma levels or dietary intake of various carotenoids and prostate cancer risk, lycopene appeared inversely associated with prostate cancer but no association was reported for a-carotene, P-carotene, lutein, zeaxanthin, or p-cryptoxanthin. - Nevertheless, a protective role of all these carotenoids (provided by tomatoes, pumpkin, spinach, watermelon, and citrus fruits) against prostate cancer was recently reported by Jian et al. ... 

Intervention trials confirmed this protective role of lycopene on prostate cancer risk. Three primary intervention studies evaluated the effect of lycopene supplementation on prostate cancer risk or on certain risk markers such as prostate-specific antigen (PSA) plasma concentration or oxidative alterations of leucocyte DNA. - All showed increases of plasma and prostate lycopene levels after diet supplementation with lycopene and inverse correlations between tumor incidence and risk biomarkers. 

Carotenoids and urino-digestive cancers — On the whole, findings from epidemiological studies did not demonstrate a protective role of carotenoids against colorectal, gastric, and bladder cancers. Indeed, most prospective and case-control studies of colorectal cancer showed no association with dietary intake or plasma level of most carotenoids. - Only lycopene and lutein were shown to be protective against colorectal cancer. Otherwise, findings from the ATBC study s showed no effect of P-carotene supplementation on colorectal cancer. 

Data concerning gastric cancer are scarce. The prospective Netherlands Cohort Study found no correlation between lutein dietary intake and gastric cancer risk, whereas findings from the Physicians Health Study and the ATBC study reported no effect of P-carotene on gastric cancer incidence. Two case-control studies and three intervention trials (ATBC, CARET, and the Physicians Health Study ) showed no association of P-carotene, lycopene, lutein, zeaxanthin, and P-cryptoxanthin. 

However, intervention trials investigating the effects of P-carotene and lycopene supplementation on CVD have not reported convincing results (Table 3.1.3). Among the seven studies reviewed herein, four primary prevention trials, namely the Multicenter Skin Cancer Prevention Study, the Beta Carotene and Retinol Efficacy Trial, the ATBC cancer prevention study, " and the Physicians Health Study have shown no association between a supplementation of P-carotene and risk of death from CVD or fatal and non-fatal MI. 

Epidemiological data on carotenoids and cerebral infarcts or strokes indicate a protective effect of P-carotene and lycopene. Indeed, the Basel prospective study, the Kuopio Ischaemic Heart Disease Risk Factor study, and the Physicians Health Study " have shown an inverse correlation between carotenoid plasma level and risk of stroke. In the same way, Hirvonen et al. demonstrated, in findings from the ATBC cancer prevention stndy, an inverse association between P-carotene dietary intake and stroke. However, clinical data on carotenoids and stroke are nonexistent and they are needed to confirm this possible protective effect of carotenoids on stroke. 

The second major difficulty is that cells and tissues in the body are exposed to numerous metabolites displaying different structures compared to the parent molecules present in plant foods. For example, it has been suggested that the metabolites of lycopene may be responsible for reducing the risk of developing prostate cancer. These metabolites may interact with nuclear receptors such as PPARs, LXR, and others. " Future research is needed to produce metabolites (enzymatically or chemically) in order to elucidate their cellular mechanisms and thus clarify their effects on human health. 

Etminan, M. et al.. The role of tomato products and lycopene in the prevention of prostate cancer a meta-analysis of observational studies. Cancer Epidemiol. Biomarkers Prev., 13, 340, 2004. 

Jian, L. et al.. Do dietary lycopene and other carotenoids protect against prostate cancer Int. J. Cancer, 113, 1010, 2005. 

Kucuk, O. et al.. Effects of lycopene supplementation in patients with localized prostate cancer, Exp. Biol. Med. (Maywood), 227, 881, 2002. van Breemen, R.B. et al.. Liquid chromatography-mass spectrometry of cis- and all-trans-lycopene in human serum and prostate tissue after dietary supplementation with tomato sauce, J. Agric. Food Chem., 50, 2214, 2002. 

Rao, A.V. and Agarwal, S., Bioavailability and in vivo antioxidant properties of lycopene from tomato products and their possible role in the prevention of cancer, Nutr. Cancer, 3, 199, 1998. 

Karas, M. et ah. Lycopene interferes with cell cycle progression and insulin-like growth factor I signaling in mammary cancer cells, Nutr. Cancer, 36,101, 2000. 

Amir, H. et ah. Lycopene and 1,25-dihydroxyvitamin D3 cooperate in the inhibition of cell cycle progression and induction of differentiation in HL-60 leukemic cells, Nutr. Cancer, 33, 105, 1999. 

Ben-Dor, A. et al.. Effects of acyclo-retinoic acid and lycopene on activation of the retinoic acid receptor and proliferation of mammary cancer cells. Arch. Biochem. Biophys., 391, 295, 2001. 

Other dietary factors implicated in prostate cancer include retinol, carotenoids, lycopene, and vitamin D consumption.5,6 Retinol, or vitamin A, intake, especially in men older than age 70, is correlated with an increased risk of prostate cancer, whereas intake of its precursor, [3-carotene, has a protective or neutral effect. Lycopene, obtained primarily from tomatoes, decreases the risk of prostate cancer in small cohort studies. The antioxidant vitamin E also may decrease the risk of prostate cancer. Men who developed prostate cancer in one cohort study had lower levels of l,25(OH)2-vitamin D than matched controls, although a prospective study did not support this.2 Clearly, dietary risk factors require further evaluation, but because fat and vitamins are modifiable risk factors, dietary intervention may be promising in prostate cancer prevention. 

Other agents, including selenium, vitamin E, lycopene, green tea, nonsteriodal anti-inflammatory agents, isoflavones, and statins, are under investigsation for prostate cancer and show promise. Selenium is a naturally occurring trace element that is an essential nutrient in the human diet.8 However, none of these agents is currently recommended for routine use outside a clinical trial. 

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