Carotenoids cancer risk

Several studies have investigated the role of dietary factors in prostate cancer risk, but results appear inconsistent. Significant effects have not been detected for dietary soya products certain vegetables, beans, fruit, rice and seaweed appear to be protective in some studies, while another has shown no protective effect from seaweed or vegetable consumption. In addition, a number of other risk factors have been shown to be associated with an increased risk of this cancer, including meat and dairy products and carotenoids. 

Many epidemiological studies have analyzed the correlations between different carotenoids and the various forms of cancer and a lot of conclusions converge toward protective effects of carotenoids. Many studies were carried out with (i-carotene. The SUVIMAX study, a primary intervention trial of the health effects of antioxidant vitamins and minerals, revealed that a supplementation of p-carotene (6 mg/day) was inversely correlated with total cancer risk. Intervention studies investigating the association between carotenoids and different types of cancers and cardiovascular diseases are reported in Table 3.1.2 and Table 3.1.3. 

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. ... 

Carotenoids and breast cancer — Among seven case-control studies investigating the correlation between different carotenoid plasma levels or dietary intakes and breast cancer risk, five showed significant inverse associations with some carotenoids. - In most cases, this protective effect was due to 3-carotene and lutein. However, one (the Canadian National Breast Screening Study ) showed no association for all studied carotenoids including (I-carotene and lutein. More recently, another study even demonstrated a positive correlation between breast cancer risk and tissue and serum levels of P-carotenes and total carotenes. Nevertheless, these observational results must be confirmed by intervention studies to prove consistent. 

Dorgan, J.F. et al.. Relationships of serum carotenoids, retinol, alpha-tocopherol, and selenium with breast cancer risk results from a prospective study in Columbia, Missouri (United States), Cancer Causes Control, 9, 89, 1998. 

Ratnasinghe, D. et al., Serum carotenoids are associated with increased lung cancer risk among alcohol drinkers, but not among non-drinkers in a cohort of tin miners, Alcohol, 35, 355, 2000. 

Slattery, M.L. et al., Carotenoids and colon cancer, Am. J. Clin. Nutr., 71, 575, 2000. Terry, P. et al., Dietary carotenoid intake and colorectal cancer risk, Nutr. Cancer, 42, 167, 2002. 

Nkondjock, A. and Ghadirian, P, Dietary carotenoids and risk of colon cancer case-control study, Int. J. Cancer, 110, 110, 2004. 

Zeegers, M.P. et al.. Are retinol, vitamin C, vitamin E, folate and carotenoids intake associated with bladder cancer risk Results from the Netherlands Cohort Study, Br. J. Cancer, 85, 977, 2001. 

Michaud DS, Feskanich DD, Rimm EB et al. (2000), Intake of specific carotenoids and risk of lung cancer in 2 prospective US cohorts, Am. J. Clin. Nutr. 92 990-997. 

By contrast, other compounds in food may decrease cancer risk (Table 21.7). Free radical scavengers such as the antioxidants, vitamins E and C, carotenoids and fla-venoids have anti-cancer activity, while vitamins A and D and other retinoids may encourage a cell to differentiate rather than proliferate (Box 21.4). Plant oestrogens in soya prodncts may be protective since they compete with human oestrogens for the oestrogen receptors in breast and ovary bnt elicit no response. 

The relationship between dietary carotenoids and risk of lung cancer has been determined in a pooled analysis of seven cohort studies (studies with the asterisk in Table 7). The results (42) indicate that /3-carotene was not associated with lung cancer, that smoking was the strongest risk factor for lung cancer, and /3-cryptoxantin (contained in citrus fruit) may modestly reduce the risk. 

CNBSSe Case-cohort11 13 5681 F No association between dietary carotenoid intake and lung cancer risk 145... 

Mannisto S, Smith-Warner SA, Spiegelman D, et al. Dietary carotenoids and risk of lung cancer in a pooled analysis of seven cohort studies. Cancer Epidemiol Biomarkers Prev 2004 13 40-48. 

I 94 Cho E, Spigenman D, Hunter DJ, etal. Premenopausal intakes of vitamin A, C, and E, folate, and carotenoids, and risk of breast cancer. Cancer Epidemiol Biomarkers Prev 2003 12 713-720. 

Le Marchand, L. et al.. Intake of specific carotenoids and lung cancer risk. Cancer Epidemiol. Biomarkers Prev., 2, 183, 1991. 

L.Le Marchand, J.H. Hankin, L.N. Kolonel, G.R. Beecher, L.R. Wilkens, L.P. Zhao. Intake of Specific Carotenoids and Lung Cancer Risk. Cancer Epidemiology, Biomarkers and Prevention, Vol. 2, pgs. 183-187,1993. 

Vogt TM, Mayne ST, Graubard Bl, Swanson CA, Sowell AL, Schoenberg JB, Swanson GM, Greenberg RS, Hoover RN, Hayes RB, Ziegler RG. Serum lycopene, other serum carotenoids, and risk of prostate cancer in US blacks and whites. Am J Epidemiol 2002 155 1023-1032. 

Dietary intakes of p-carotene or provitamin A carotenoids were inversely associated with limg cancer risk in only 4 out of 11 prospective studies. " " " " In a... 

Rohan, T.E., Jain, M., Howe, G.R., and Miller, A.B., A cohort study of dietary carotenoids and lung cancer risk in women (Canada), Cancer Causes Control, 13,231,2002. 

De Stefani, E., Boffetta, P., Brennan, P., Deneo-Pellegrini, H., Carzoglio, J.C., Ronco, A., and Mendilaharsu, M., Dietary carotenoids and risk of gastric cancer a case-control study in Uruguay, Ewr. J. Cancer Prev., 9, 329, 2000. 

Schuurman, A.G., Goldbohm, R.A., Brants, H.A., and van den Brandt, P.A., A prospective cohort study on intake of retinol, vitamins C and E, and carotenoids and prostate cancer risk (Netherlands), Cancer Causes Control, 13, 573,2002. 

E., Carotenoids, alpha-tocopherols, and retinol in plasma and breast cancer risk in northern Sweden, Cancer Causes Control, 12, 529,2001. 

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