Intestinal polyps

Asbestos fiber > 10 micrometer 7 million fibers per liter 7MFL Increased risk of developing benign intestinal polyps Decay of asbestos cement in water mains erosion of natural deposits... 

The link between Cox-2 and polyps has been most extensively studied in an animal model of FAP, the adenomatous polyposis coli gene knockout mouse, which develops multiple intestinal polyps. In this model, both sulindac and a Cox-2 inhibitor are effective in producing regression of adenomas. When this knockout mouse was crossbred to a Cox-2 knockout mouse to produce a double adenomatous polyposis coli/Cox-2 knockout, the development of intestinal polyposis was markedly reduced (Oshima etal., 1996). 

Chrysotile (intermediate range) Rat 0.82 60% >5.4 im Benign intestinal polyps (males) Not significant based on concurrent Some evidence of carcinogenicity NTP 1985 ... 

In a lifetime feeding study in rats, exposure to intermediate length chrysotile fibers led to an increased incidence of intestinal polyps (NTP 1985). Based on these data, EPA (1985b) calculated that the 10 " risk level corresponded to an asbestos concentration of 7.1x10 17L in drinking water. 

Paulsen JE, Elvsaas I-KO, Steffensen 1-L, Alexander J. A fish oil derived concentrate enriched in eicosapentaenoic and docosahexaenoic acid as ethyl ester suppresses the formation and growth of intestinal polyps in the Min mouse. Carcinogenesis 1997 18 1905-1910. 

In a study by Kearney et al. (1995) of the Department of Nutrition, Harvard School of Public Health, low folic acid levels were found to correlate with an increase in cancerous intestinal polyps, as well as with cancer in general. 

Colin Tuma has had an intestinal adenocarcinoma resected, but there were several metastatic nodules in his liver (see Chapters 12 and 13). He completed his second course of chemotherapy with 5-fluorouracil (5-FU) and had no serious side effects. He assured his physician at his most recent checkup that, this time, he intended to comply with any instructions his physicians gave him. He ruefully commented that he wished he had returned for regular examinations after his first round of surgery for benign intestinal polyps. 

Lai, G., Ash, C., Hay, K., Redston, M., Kwong, E., Hancock, B. et al.. Suppression of intestinal polyps in Msh2-deficient and non-Msh2-deficient multiple intestinal neoplasia mice by a specific cyclooxygenase-2 inhibitor and by a dual cyclooxygenase-1/2 inhibitor. Cancer Res., 61,6131-6136,2001. 

Min mice have a truncating mutation in the murine APC gene at a position similar to that found in many FAP patients and develop multiple intestinal adenomas [24]. Heterozygous APC mice were therefore used to evaluate the efficacy of potential chemopreventative compounds on development of intestinal polyps [25]. The compounds tested were sulindac, a non-steroidal anti-inflammatory drag with estabUshed chemopreventative activity, and EKB-569, an irreversible inhibitor of the epidermal growth factor receptor kinase. 

Virtual CT colonoscopy for early detection of intestinal polyps (which might be pre-cancerous lesions) and colorectal cancer (Mulhall et al. 2005) ... 

In an in vivo model of intestinal tumorigenesis in Apc mice, feeding of grape seed extract reduced the total number of intestinal polyps compared to control mice [116]. The findings paralleled with decreased cyclin D1 and c-Myc protein levels in the small intestine along with downregulation in expression of other important molecules such as COX-2, iNOS, and p-catenin and increased expression... 

Khor, TO. et aL (2006) Pharmacogenomics of cancer chemopreventive isothiocyanate compound sulforaphane in the intestinal polyps of ApcMin/ + mice. Biopharm Drug Dispos 27 (9), 407-420... 

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