Traditional Processed Meat Products Re-designed Towards Inulin-rich Functional Foods Reduce Polyps in Two Colorectal Cancer Animal Models.

Inulin-rich foods exert a prebiotic effect, as this polysaccharide is able to enhance beneficial colon microbiota populations, giving rise to the in situ production of short-chain fatty acids (SCFAs) such as propionic and butyric acids. These SCFAs are potent preventive agents against colorectal cancer due to their histone deacetylases inhibitory properties, which induce apoptosis in tumor colonocytes. As colorectal cancer is the fourth most common neoplasia in Europe with 28.2 new cases per 100,000 inhabitants, a cost-effective preventive strategy has been tested in this work by redesigning common porcine meat products (chorizo sausages and cooked ham) consumed by a substantial proportion of the population towards potential colorectal cancer preventive functional foods. In order to test the preventive effect of these inulin-rich meat products against colorectal cancer, an animal model (Rattus norvegicus F344) was used, involving two doses of azoxymethane (10 mg/kg) and two treatments with dextran sodium sulfate (DSS) during a 20-week assay period. Control feed, control sausages, functional sausages (15.7% inulin), control cooked ham and functional cooked ham (10% inulin) were used to feed the corresponding animal cohorts. Then, the animals were sacrificed and their digestive tract tissues were analyzed. The results showed a statistically significant 49% reduction in the number of colon polyps in the functional meat products cohorts with respect to the control meat products animals, as well as an increase in the cecum weight (an indicator of a diet rich in prebiotic fiber), a 51.8% increase in colon propionate production, a 39.1% increase in colon butyrate concentrations, and a reduction in the number of hyperplastic Peyer's patches. Metagenomics studies also demonstrated colon microbiota differences, revealing a significant increase in Bacteroidetes populations in the functional meat products (mainly due to an increase in Bacteroidaceae and Prevotellaceae families, which include prominent propionate producers), together with a reduction in Firmicutes (especially due to lower Lachnospiraceae populations). However, functional meat products showed a remarkable increase in the anti-inflammatory and fiber-fermentative Blautia genus, which belongs to this Lachnospiraceae family. The functional meat products cohorts also presented a reduction in important pro-inflammatory bacterial populations, such as those of the genus Desulfovibrio and Bilophila. These results were corroborated in a genetic animal model of CRC (F344/NSlc-Apc1588/kyo) that produced similar results. Therefore, processed meat products can be redesigned towards functional prebiotic foods of interest as a cost-effective dietary strategy for preventing colorectal cancer in human populations.

De Novo Development of Hamartomatous Duodenal Polyps in a Patient With Short Bowel Syndrome During Teduglutide Therapy: A Case Report.

Teduglutide (TG) is approved for the treatment of parenteral nutrition (PN)-dependent adult patients with short bowel syndrome (SBS). Its well-known adverse effect is expedited growth of colon polyps and potential formation of new polyps. Apart from animal studies, de novo development of duodenal polyps in a patient during TG therapy has not been reported in the literature. We report a case of a 71-year-old man with SBS on TG who developed multiple new duodenal polyps that were found incidentally during a diagnostic endoscopy. Furthermore, an accelerated growth of duodenal polyps was noted while on TG therapy, suggesting a potential trophic effect of TG on these polyps. There are no current recommendations for the surveillance of intestinal polyps in patients on TG therapy, but we recommend exercising caution and possible need for surveillance based on this case report.

Nature of tissue-bound lithocholic acid and its implications in the role of bile acids in carcinogenesis.

Lithocholic acid, a monohydroxy secondary bile acid, is present in tissues in two forms. One form is extractable with 95% ethanol-0.1% ammonia (soluble lithocholate), and the other form is firmly bound to tissue residues and can be released only by the bile salt-deconjugating enzyme, clostridial cholanoylamino acid hydrolase (tissue-bound lithocholate). Studies on bile salt-protein interactions revealed that lithocholic acid had amino group-modifying activity specifically directed against the basic side group of lysine residues. Degradative procedures yielded N-epsilon-lithocholyllysine, confirmed by comparison with the authentic compound synthesized in our laboratories. Studies on the distribution of tissue-bound lithocholate in tissues have revealed high concentrations of this form of lithocholate in livers of rats treated with the carcinogen, methylazoxymethanol. In light of these observations, the role of bile acids, and specifically lithocholic acid, as promoters of tumorigenesis must be further investigated.

Bromodichloromethane, a trihalomethane that produces neoplasms in rodents.

Bromodichloromethane, a trihalomethane found in water supplies after chlorination, was administered by gavage in corn oil to male and female F344/N rats and B6C3F1 mice for up to 2 years at dose levels of 0, 50, or 100 mg/kg to rats, 0, 25, or 50 mg/kg to male mice, and 0, 75, or 150 mg/kg to female mice. Survival at 2 years in rats and in male mice was comparable among groups and was greater than 50% at the termination of the experiment. Survival in female mice was greater than 50% in all groups until week 84 but was reduced toward the end of the study because of ovarian abscesses in some female mice. There was clear evidence of carcinogenicity in males and females of both species as shown by increased incidences of tubular cell adenomas and adenocarcinomas in the kidney and adenocarcinomas and adenomatous polyps in the large intestine in male and female rats, increased incidences of tubular cell adenomas and adenocarcinomas in the kidney of male mice, and increased incidences of hepatocellular adenomas and carcinomas in female mice. Of the three trihalomethanes studied to date in the National Cancer Institute/National Toxicology Program (chloroform, chlorodibromomethane, or bromodichloromethane) bromodichloromethane caused the widest spectrum of neoplasms in rodents.

Involvement of prostaglandin E receptor subtype EP(4) in colon carcinogenesis.

Accumulating evidence indicates that overproduction of prostanoids attributable to overexpression of cyclooxygenase-2 (COX-2) plays an important role in colon carcinogenesis. We have shown recently that the prostaglandin (PG) E receptor, EP(1), but not EP(3), is involved in mouse colon carcinogenesis. In line with our previous study, here we examined the role of prostanoid receptors in colon carcinogenesis using six additional lines of knockout mice deficient in prostanoid receptors EP(2), EP(4), DP, FP, IP, or TP. The animals were treated with the colon carcinogen, azoxymethane (AOM), and examined for the development of aberrant crypt foci (ACFs), putative preneoplastic lesions in the colon. Formation of ACFs was decreased only in the EP(4)-knockout mice, to 56% of the wild-type level. To confirm these results, we also examined the inhibitory effects of an EP(4)-selective antagonist, ONO-AE2-227, in the diet on the formation of AOM-induced colon ACFs in C57BL/6Cr mice and on the development of intestinal polyps in Min mice. ONO-AE2-227 at a dose of 400 ppm reduced the formation of ACFs to 67% of the control level, and intestinal polyp numbers in Min mice receiving 300 ppm were decreased to 69% of the control level. Plating efficiency assays showed that addition of 1.0 microM ONO-AE1-329, an EP(4)-selective agonist, resulted in a 1.8-fold increase in the colony number of the human colon cancer cell line, HCA-7, similar to the effect of PGE(2). Moreover, EP(4) mRNA expression was clearly observed in normal colon mucosa and colon tumors in mice. Our previous and present results indicate that PGE(2) contributes to colon carcinogenesis through its actions mediated through EP(1) and EP(4) receptors; therefore, antagonists for these two receptors may be good candidates as chemopreventive agents against colon cancer.

Association between colorectal polyps and hypertension treatment.

OBJECTIVE: Patients who take drugs regularly are increasing, not least due to metabolic and orthopedic diseases. In the present study we aimed to investigate the association between the use of drugs, such as non-steroidal anti-inflammatory drugs (NSAIDs) and low-dose aspirin, and colorectal polyps diagnosed based on colonoscopic findings. METHODS: In total, 1318 consecutive patients who underwent total colonoscopy for the first time were cross-sectionally analyzed. Personal data including comorbidities and all medications were obtained by a questionnaire. Their blood pressure, body weight and waist circumference were measured just before the colonoscopic examination. RESULTS: Colorectal polyps were found in 577 (43.8%) patients, with a prevalence of 57.6% (296/514) in patients receiving antihypertensive treatment and 35.0% (281/804) in patients not undergoing such treatment. A multivariate analysis showed that age, waist circumference, alcohol consumption, smoking and the use of antihypertensive drugs were independent risk factors for colorectal polyps. In a secondary multivariate analysis incorporating the parameters of measured blood pressure and medication status, the number of antihypertensive drugs was strongly associated with the risk of colorectal polyps, whereas blood pressure showed no significant association. CONCLUSIONS: The use of antihypertensive drug may be a risk factor for colorectal polyps. Furthermore, this risk increases with the intensive use of antihypertensive drugs.

The cytochemical demonstration of beta-glucuronidase in colon neoplasms of rats exposed to azoxymethane.

Colon tumors induced with azoxymethane in male Fischer rats were cytochemically analyzed for beta-glucuronidase using naphthol AS-B1 glucuronide (6-bromo-2-hydroxy-3-naphthoyl-O-anisidine) as a substrate and hexazonium pararosanin as a diazo reagent. This method effectively localizes the bulk of beta-glucuronidase in the surface epithelium, the lamina propria and in the endothelial cells of the lymphoid sinuses and postcapillary venules. Polypoid lesions, adenocarcinomas and mucinous adenocarcinomas show no difference in the amount or in the localization of beta-glucuronidase; however, mucinous adenocarcinomas show a slight increase in the amount of beta-glucuronidase. The few tumors that did metastasize to lymph nodes did not show any difference in their enzyme patterns. Intestinal crypts that show a change in size and shape have a definite increase in beta-glucuronidase activity. An increase in the activity of this enzyme can also be seen in well defined neoplasms as opposed to normal areas of the colon.

Intestinal disease and the urban environment.

Factors in the urban environments of highly industralized societies are important causes of disease. This review examines urban diseases of small and large intestine. The urban environment is pervaded by chemicals including drugs, food additives, pesticides, industrial products, etc., which are potential causes of disease. Examples of typical urban, as contrasted with rural, intestinal disease are considered in terms of differing etiological factors. Urban intestinal disease is examined from the following standpoints: the population at risk; the chemical agents to which the population is exposed; a model for the physiology of distribution and metabolism of chemicals in relation to the alimentary tract; the application of this model to treatment of an industrial disease; a major urban disease of the alimentary tract, carcinoma of the colon, considered in terms of this model; approaches to characterizing, identifying, and controlling urban intestinal disease.

Phenolphthalein-containing laxative use in relation to adenomatous colorectal polyps in three studies.

Phenolphthalein, the active ingredient in many laxatives, was recently found to be a carcinogen in animal models. Human data suggest a laxative-colon cancer association, but few data specifically address the effects of phenolthalein-containing laxatives. We examined use of phenolphtalein-containing laxatives in relation to occurrence of adenomatous colorectal polyps in data from three case-control studies. The study conducted in Los Angeles, California (1991-1993), and the two studies conducted in North Carolina (1988-1990 and 1992-1995) altogether included 866 cases and 1,066 controls. The prevalence of using phenolphthalein-containing laxatives at least once a week in the recent past, however, was less than 5% among these subjects. The multivariate-adjusted odds ratios associated with recent use of phenolphthalein-containing laxatives once a week or more were 1.8 -95% confidence interval (CI), 0.5-6.2] in Los Angeles, 1.0 (CI, 0.4-2.2) in North Carolina (1988-1990), and 1.1 (CI, 0.2-5.7) in North Carolina (1992-1995). For use of other types of laxatives, the corresponding odds ratios were 1.3 (CI, 0.9-1.9) in Los Angeles, 1.0 (CI, 0.5-1.7) in North Carolina (1988-1990), and 0.9 (CI, 0.4-1.8) in North Carolina (1992-1995). Although the low prevalence of frequent use made for relatively wide confidence intervals, overall these data suggest that use of phenolphthalein-containing laxatives does not increase risk of adenomatous colorectal polyps.

Milk and dairy products in cancer prevention: focus on bovine lactoferrin.

Milk and dairy products constitute an important part of the western style diet. A large number of epidemiological studies have been conducted to determine effects of consumption on cancer development but the data are largely equivocal, presumably reflecting the different included components. It has been proposed that whereas fats in general could promote tumor development, individual milk fats like conjugated linoleic acid could exert inhibitory effects. There is also considerable evidence that calcium in milk products protects against colon cancer, while promoting in the prostate through suppression of circulating levels of 1,25-dihydroxyvitamin D3. Whey protein may also be beneficial, as shown by both animal and human studies, and experimental data have demonstrated that the major component bovine lactoferrin (bLF), inhibits colon carcinogenesis in the post-initiation stage in male F344 rats treated with azoxymethane (AOM) without any overt toxicity. The incidence of adenocarcinomas in the groups receiving 2% and 0.2% bLF were thus 15% and 25%, respectively, in contrast to the 57.5% control value (P<0.01 and P<0.05, respectively). Results in other animal models have provided further indications that bLF might find application as a natural ingredient of milk with potential for chemoprevention of colon and other cancers.

Carcinogenicity of lifelong administration of capsaicin of hot pepper in mice.

Capsaicin was administered in a semisynthetic powdered diet at 0.03125% level for the lifespan of Swiss mice starting from 6 weeks of age. As a result of C treatment, tumors of the cecum were induced in 22% of females and 14% of males, whereas the corresponding tumor incidences in untreated female and male controls were both 8%. Histopathologically, the tumors were classified as benign polypoid adenomas. Capsaicin is the main pungent principle of hot pepper, which is consumed in high quantities by humans worldwide. The capsaicin content of some chili varieties ranges up to 0.53%.

Endoscopic diagnosis of chemically induced autochthonous colonic tumors in rats.

The suitability of using coloscopy as a diagnostic method is investigated with respect to colonic carcinomas induced locally by the administration of N-nitrosoacetoxymethyl-methylamine, N-methyl-N-nitrosourea, and methylnitro-nitrosoguanidine, or systemically by subcutaneous injection of 1,2-dimethylhydrazine in Sprague-Dawley rats. The endoscopic diagnostic examination proved to be clearly superior to methods of animal inspection, palpation, investigation for occult blood and exploratory laparotomy which have so far been employed in animal experiments with small rodents. The relevance of this method is discussed for the early detection of chemically induced colonic tumors, and the observation of tumor development under experimental cytostatic therapy.

Insulin therapy and colorectal adenomas in patients with diabetes mellitus.

BACKGROUND: Patients with type 2 diabetes mellitus (DM) are at increased risk for colorectal adenomas and cancer because of endogenous hyperinsulinemia. Exogenous insulin therapy has been associated with higher colorectal cancer incidence. The aim of this study was to evaluate the association between exogenous insulin therapy and adenoma formation, accounting for duration of therapy and location and stage of the adenoma. METHODS: We conducted a cross-sectional study of patients with type 2 diabetes between the ages of 50 and 80 years who completed full colonoscopies. Cases were patients with any adenoma on index colonoscopy. Patients without any adenoma composed the control group. Multivariable logistic regression was used to calculate odds ratios (OR) and associated confidence intervals (CI). RESULTS: Compared with the controls, case patients (n = 196) did not have a significantly increased odds of insulin exposure, when exposure was defined as 12 months or more of insulin use compared with no insulin. However, the odds of insulin exposure among the cases was significantly increased when exposure was defined as 18 months or more (OR 1.6, 95% CI 1.1-2.5), 24 months or more (OR 1.7, CI 1.1-2.6), and 36 months or more (OR 2.0, 95% CI 1.2-3.4) of insulin use (test for trend P = 0.05). A similar trend in insulin exposure was seen among type 2 diabetics with advanced adenomas. Adenoma location was not significantly affected by insulin therapy. CONCLUSIONS: Chronic insulin therapy is associated with increased risk of colorectal adenomas in patients with type 2 diabetes. IMPACT: Diabetes patients receiving insulin may need more stringent colon cancer screening.