Colon cancer, risk

Colorectal Cancer. Colorectal cancer occurs frequently in the UK population but is historically rare in Asia. Rates in Japan have, however, increased rapidly in recent years.Interestingly, there appears to be an association between oestrogen exposure and colon cancer risk has been shown to increase in women with increasing age of first live birth, and to decrease with increasing parity (number of children). In addition, many colon tumours express sex hormone receptors, and this is thought to play a part in development of the tumours. "... 

Diets high in red meat and low in green vegetables have been associated with increased colon cancer risk and the opposite has been postulated for diets rich in green vegetables. A plausible explanation for an increased colon cancer risk is that dietary haem is metabolized in the gut to a factor that increases colonic cytotoxicity and hyperproliferation, which are considered important risk factors in the development of cancer. In this sense, it has been shown that spinach and isolated natural chlorophyll, but not sodium-copper chlorophyUin, prevented the proliferation of colonic cells and may therefore reduce colon cancer risk. It has been speculated that haem and chlorophylls, due to their hydrophobicity, form a complex, thus preventing the metabolism of haem. ... 

Dietary and pharmacologic agents influence the risk of colon cancer. Diets high in fat and low in fiber are associated with increased colon cancer risk, whereas the regular use of aspirin (and other NSAIDs) and calcium supplementation may decrease the risk of colon cancer. 

McCullough ML, Robertson AS, Chao A, Jacobs EJ, Stampfer MJ, Jacobs DR, Diver WR, Calle EE and Thun MJ. 2003. A prospective study of whole grains, fruits, vegetables and colon cancer risk. Cancer Causes Control 14(10) 959-970. 

The WHI study was the first randomized, controlled trial to confirm that hormone therapy reduces colon cancer risk. 

Goodman JE, Bowman ED, Chanock SJ, Alberg AJ, Harris CC. (2004) Arachidonate lipoxygenase (ALOX) and cyclooxygenase (COX) polymorphisms and colon cancer risk. Carcinogenesis. 25, 2467-2472. 

C. Bernstein, H. Bernstein, H. Garewal, P. Dinning, R. Jabi, R. E. Sampliner, M. K. McCuskey, M. Panda, D. J. Roe, L. L Heureux and C. Payne, A bile-acid-induced apoptosis assay for colon cancer risk and associated quality control studies. Cancer Res., 1999, 59(10), 2353. 

CA033 Grubben, M. J., C. C. Van Den Braak, R. Broekhuizen, et al. The effect of unfiltered coffee on potential biomarkers for colonic cancer risk in healthy volunteers a randomized trial. Alim Pharm Therap 2000 14(9) 1181-1190. 

The possible role of isoflavonoids in the prevention of cancer and in particular hormone-dependent cancers such as breast and prostate cancer is currently extensively investi-gated. " " In addition, consumption of soy foods rich in isoflavones has been weakly associated with reduced colon cancer. Colon cancer risk is influenced by estrogen exposure although the mechanism of action has not been fully elucidated, studies with estrogen receptor a (see Section 7.3.3) knockout mice indicate that it may be independent of estrogen receptor... 

Anon. Folate, alcohol, methionine, and colon cancer risk is there a unifying theme Nutr Rev 52 18-20, 1994. 

Colorectal cancer Cancers of the colorectum are common in economically developed areas. Five studies have reported on tomato intake in relation to colorectal cancer risk. One study in the U.S. reported statistically significant inverse associations between tomato consumption and colon cancer risk for men and women. 

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). 

Figure 26.3 illustrates a hypothetical example of interaction between intake of well-done meats, intake of dairy products, and colon cancer risk. The best candidates for interaction with meat intake and colon cancer risk are probably genetic susceptibility factors, which are discussed in detail in Section 26.4. To our knowledge, nongenetic interactions with HCA intake and colon cancer risk have not been studied. Animal studies have shown that dairy products were protective of aberrant crypts (a preneoplastic colonic lesion) induced by 2-amino-l-methyl-6-phenylimid-azo(4,5-b)pyridine (PhIP, a specific HCA). In this hypothetical example, a modest risk is observed for HCA intake and colon cancer in the total population (OR = 1.47). However, when the population is stratified according to dairy consumption, an increased risk for HCA intake is only observed in the strata of low dairy consumption (OR = 2.43), suggesting that the effect of high intake of HCAs from meat may only be relevant when intake of dairy products is low. Source Tavan et al. (2002). 

Figure 263. Hypothetical example of effect modification between consumption of dairy products, HCA intake, and colon cancer risk.

The Lnvesfigators (Thun ei al., 1992) found that increased vegetable and grain intake was associated with a lower risk for death by colon cancer (Figure 11.12). Most, but not all, of the plant foods were associated with this lower risk. It is curious to point out that there was no association of colon cancer risk with the intake of potatoes and tomatoes. In contrast, most other existing epidemiological studies (50 different studies in all) that addressed all types of cancers (and asked about tomatoes) found that tomatoes have a protective effect (Table 12 in Stein-metz and Potter, 1996). 

Greenwald, P., Lanza, E., and Eddy, G. A. (1987). Dietary fiber in the reduction of colon cancer risk. /. Am. Diet. Assoc. 87,1178-1188. 

Berlau, J., Glei, M. and Pool-Zobel, B.L. (2004) Colon cancer risk factors from nutrition. Analytical and Bioanalytical Chemistry, 378 (3), 737-743. 

Colorectal cancer is the fourth most common cancer and the second leading cause of cancer death in the United States (see Chap. 127). The WHl was the first randomized, controlled trial to confirm that hormone therapy reduces colon cancer risk. Compared with placebo, 6 fewer colorectal cancers are reported per year in every 10,000 women taking hormone therapy. ... 

Thus, consider, for instance, ubiquitous aspirin, which is given a chapter in Moss s book. Studies have shown that aspirin intake may reduce colon cancer risk by some 50%. The effect seems to be enhanced by also taking nicotinic add (niacin), or vitamin B3. 

Although fruit and, more consistently, vegetable intakes are inversely associated with colorectal cancer risk, the epidemiological evidence for vitamin C as a specific protective factor is less consistent. Since 1990, two out of four prospective studies have observed a significant inverse association between vitamin C intake and the risk of colon or rectal cancer. In a prospective cohort study that followed 4277 elderly men and 7300 elderly women over 8 years, women who consumed more than 225mg/d of vitamin C had a 39% lower risk of colon cancer than women who consumed less than 155mg/d, but no association between vitamin C intake and colon cancer risk was observed for men. A similar decrease in colon cancer risk was observed in women who took vitamin C supplements. A recent study of colon cancer mortality in more than 700,000 U.S. men and women found that the use of vitamin C supplements for at least 10 years was associated with a 60% reduction in rectal cancer risk, but was not significantly associated with colon cancer risk. ... 

Pierre, R, G. Peiro, S. Tache, A. J. Cross, S. A. Bingham et al. 2006. New marker of colon cancer risk associated with heme intake 1, 4-Dihydroxynonane mercapturic acid,... 

Covers M.J., Gannon M.J., Dunshea F.R., Gibson P.R., Muir J.G., Wheat bran affects the site of fermentation of resistant starch and luminal indexes related to colon cancer risk A study in pigs. Gut, 45(6), 1999, 840-847. 

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