Vitamin E and Cancer

Although the evidence for vitamin E protection against cancer is weaker than for cardiovascular disease, vitamin E forms may also act as chemoprotective agents that 

Functional Foods Biochemical and Processing Aspects, Volume 2 

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Constantinou, C. Papas, A. Constantinou, A.1.2008. Vitamin E and cancer An insight into the anticancer activities of vitamin E isomers and analogs. Int. J. Cancer 123 739-752. 

Data about the preventive effect of vitamin E on cardiovascular diseases are corttradictory. Observational studies showed that the consumption of vitamin E reduces the risk, but large interventional studies involving thousands of people could not verify this. The latter test types are more rehable in general. Similarly ambiguous is the relationship between vitamin E and cancer. There are numerous positive interventional studies, but an especially significant test showed that high... 

Thus, it is uncertain to what extent the apparent protective effects of fruit and vegetable consumption on risk of stomach cancer can be attributable to their phytoestrogen content. This appears not to have been studied directly, and other constituents such as ascorbic acid (vitamin C), a-tocopherol (vitamin E) and /1-carotene may be potentially protective. 

ALPHA-TOCOPHEROL BETA-CAROTENE (ATBC) CANCER PREVENTION STUDY GROUP (1994) The effect of vitamin E and beta carotene on the incidence of lung cancer and other cancers in male smokers , New Engl J Med, 330, 1029. 

BYERS T and GUERRERO N (1995) Epidemiologic evidence for vitamin C and vitamin E in cancer prevention , Am J Clin Nutr, 62, 1385S-92S. 

The risk of colon cancer appears to be inversely related to calcium and folate intake. Calciums protective effect may be related to a reduction in mucosal cell proliferation rates or through its binding to bile salts in the intestine, whereas dietary folate helps in maintaining normal bowel mucosa. Additional micronutrient deficiencies have been demonstrated through several studies to increase colorectal cancer risk and include selenium, vitamin C, vitamin D, vitamin E, and 3-carotene however, the benefit of dietary supplementation does not appear to be substantial.11... 

Radiation is one of the most important known environmental stimuli of cancer development. This environmental factor becomes especially dangerous for humans living in the areas affected by irradiation from nuclear accidents. Earlier we found that the administration of a mixture of vitamin E and a-lipoic acid to children living in the area of Chernobyl nuclear accident significantly and synergistically suppressed leukocyte oxygen radical overproduction [211]. Thus a-lipoic acid and a-lipoic acid + vitamin E supplements may be of interest as antioxidant preventive agents for the treatment of radiation-induced cancer development. 

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. 

Prostate cancer effect. Saw palmetto, vitamin E, and selenium supplements were used by 26.5% of the questioned men diagnosed with prostate cancer . PC-SPES, an herbal mixture of chrysanthemum, isatis, licorice, Ganoderrm lucidum, Panax pseudo-ginseng, Rabdosia rubescens, saw palmetto. 

Viscum album L. subsp. coloratum Kom. V. album L. subsp. coloratum Kom. f. rubroaurantiacum (Makino) Kitag. V. coloratum (Kom.) Nakai Hu Ji Shang (Asiatic mistletoe) (leaf, stem) Oleanolic acid, beta-amyrin, fatty acids, mesoinositol, flavoyadorinin, homoflavoyadorinin, lupeol, myristic acid, agglutinins, alkaloids, quercitol, querbrachitol, quencetine, acetylcholine, choline, histamine, tyramine, vitamins E and C.33-450 Antihypertensive, prolong the life of patients with late stage stomach cancer. 

Viscum album L. China Oleanolic acid, beta-amyrin, mesoinositol, flavoyadorinin, homoflavoyadorinin, lupeol, myristic acid, agglutinins, alkaloids, quercitol, querbrachitol, vitamins E and C.33 Antihypertensive, prolong the life of patients with late stage of stomach cancer. 

Laboratory studies of vitamin and mineral inadequacy associate such deficiencies with DNA damage, which indicates that the vitamin and mineral content of fruits and vegetables may explain the observed association between fruit and vegetable intake and cancer risk. Antioxidants such as vitamin C (whose dietary source is fruits and vegetables), vitamin E, and selenium... 

The strongest effect in clinical trials was for a protective effect of vitamin E against cancers of the prostate and colon.48 More well-done trials will increase the information about the usefulness of supplements in cancer prevention. 

R. E. Patterson, A. R. Kristal, and M. L. Neuhouser, Vitamin Supplements and Cancer Risk Epidemiologic Research and Recommendations, in A. Bendich and R. J. Deckelbau, eds., Primary and Secondary Preventive Nutrition Totowa, N.J. Humana Press, 2001), pp. 21-43. 

Takagi, A., Sai, K., Umemura, T., Hasegawa, R. Kurokawa, Y. (1995) Inhibitory effects of vitamin E and ellagic acid on 8-hydroxydeoxyguanosine formation in liver nuclear DNA of rats treated with 2-nitropropane. Cancer Lett., 91, 139-144... 

Prostate cancer is the most common cancer in U.S. males, and there is evidence that dietary fat, soy proteins, vitamin E, and selenium affect risk for this disease. Furthermore, it has been shown that consumption of lycopene and lycopene-containing foods (tomato and tomato paste) is associated with reduced risk of prostate cancer. 

The two largest studies, Nurse s Health Study (NHS) and Health Professional Follow-up Study (HPFS), were also examined together for the relationship of vitamin E and colon cancer but the findings do not provide consistent support of an inverse association between supplemental vitamin E and colon cancer risk (26). 

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