Tumor prevention

E 0 Unadjusted test gives a valid picture of the possible tumor-preventive capacity of the treatment. 

I 0 Longer survival in treated groups may mask tumor-preventive capacity of treatment. 

Selective COX-2 inhibitors have also been shown to prevent early and late forms of colorectal neoplasia in rat models. Reddy et al. showed that administration of celecoxib inhibited aberrant colonic crypt foci (ACF) induction and multiplicity by about 40-49% in an azoxymethane-induced ACF rat model (81). Later the same investigators also showed that dietary administration of celecoxib can inhibit both the incidence and multiplicity of colon tumors by about 93 % and 97 %, respectively in the same rat model (82). Other researchers reported similar results with the Min mouse model (52). There is little data on human clinical trials with selective COX-2 inhibitors for colorectal tumor prevention. Recently Steinbach et al. conducted a double-blind, placebo-controlled study with 77 patients with FAP, and reported that treatment with celecoxib, a selective COX-2 inhibitor, for 6 mo led to a significant reduction (28%) in the number of colorectal polyps in these patients (50). Collectively, COX-2 nonspecific or specific NSAIDs appear to have chemopreventive activity against colorectal cancer development. Selective... 

Tumor prevention. The effect of kernel fiber on metabolic activity of intestinal and... 

Subcutaneous injections of CVS near the tumor prevented weight loss in the tumor-inoculated, 5FU-treated mice. Fig. (13)A. CVS might prevent the adverse effects of 5FU in tumor-bearing states. 

In vivo studies using mouse models have proved that curcumin modifies apoptosis resistance, leading to the inhibition of tumor formation and the prevention of adenoma development in the intestinal tract. The chemopreven-tive effect of curcumin for intestinal tumors in Min/+ mice was investigated. A dietary level of 0.15% curcumin decreased tumor formation in Min—/— mice by 63%. Examination of intestinal tissue from the treated animals showed the tumor prevention by curcumin was associated with increased enterocyte apoptosis and proliferation. Curcumin also decreased expression of the oncoprotein (S-catenin in the erythrocytes of the Min/+ mouse, an observation previously associated with an antitumor effect. Curcumin enhanced PhlP-induced apoptosis and inhibited PhIP-induced tumorigenesis in the proximal small intestine of Ape (min) mice. Experiments performed on intestinal tumors in C57BL/6J-Min/+ (Min/+) mice demonstrated that curcumin has a regulatory role in lymphocyte-mediated immune function [Churchill et al., 2000]. Furthermore, levels of COX-2 protein expression have been found to reflect the retardation of adenoma development in mouse intestines after treatment with curcumin [Tunstall et al., 2006]. 

Koizumi A, Wada Y, Tuskada M, et al. A tumor preventive effect of dietary restriction is antagonized by a high housing temperature through deprivation of torpor. Mech Ageing Dev 1996 92 67-82. 

The biological activity of different Se species for tumor prevention has been studied by Ip et al. in several experimental models [36D38]. On the basis of their results, the highest activity was found for methylselenocysteine followed by selenite, selenocystine, and dimethylselenoxide [36]. In a more recent study that included different alk(en)ylselenocysteines and their y-glutamvl derivatives, high cancer preventive activity was also observed for methylselenocysteine [39]. In addition to inorganic forms and possible Se metabolites, the activity of the synthetic compound [l,4-phenylenebis(methylene)selenocyanate] has been tested [40, 41],... 

Lemonnier, L.A., Dillehay, D.L., Vespremi, M.J., Abrams, J., Brody, E., Schmelz, E.M. 2003. Sphingomyelin in the suppression of colon tumors prevention versus intervention. Arch. Biochem. Biophys. 419, 129-138. 

Merkel cell carcinoma, and human lung squamous cell carcinoma cell hues in cultures. The tumor-prevention and anticancer activities of aloe are due mostly to the immune stimulation and immune modulation through activation of macrophages (antigens), causing the release of substances like interferons, interleukines, and tumor necrosis factor. A/oe vera gel inhibited angiogenesis, a process of forming new blood vessels to feed the tumor. It also potentiated the effects of 5-fluorouracil and cyclophosphamide in combination therapy. ... 

Moret-Tatay I, Diaz J, Marco FM, Crespo A, Alino SF (2003) Complete tumor prevention by engineered tumor cell vaccines employing nonviral vectors. Cancer Gene Ther 10 887-897... 

Dihal AA, van der Woude H, Hendriksen PJ, Charif H, Dekker LJ, Ijsselstijn L, de Boer VC, Alink GM, Burgers PC, Rietjens IM, Woutersen RA, Stierum RH (2008) Transcriptome and proteome profiling of colon mucosa from quercetin fed F344 rats point to tumor preventive mechanisms, increased mitochondrial fatty acid degradation and decreased glycolysis. Proteomics 8 45-61... 

Fukui, M., Fujino, T., Tsutsui, K. et al. (2001) The tumor-preventing effect of a mixture of several lactic acid bacteria on 1,2-dimethylhydrazine-induced colon carcinogenesis in mice. Oncol. Rep., 8, 1073-1078. 

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