Chemoprevention, phenolic compound

Rao, C.V., Rivenson, A., Simi, B., and Reddy, B.S., Chemoprevention of colon carcinogenesis by dietary curcumin, a naturally occurring plant phenolic compound. Cancer Res., 55, 259, 1995. 

Tanaka, T., Kojima, T., Suzui, M., and Mori, H., Chemoprevention of colon carcinogenesis by the natural product of a simple phenolic compound protocatechuic acid suppressing effects on tumor development and biomarkers expression of colon tumorigenesis. Cancer Res., 53, 3908-... 

Caffeic Acid Phenethyl Ester (CAPE). CAPE, a phenolic compound with antioxidant properties, is an active ingredient derived from honeybee propolis (52). CAPE has antiviral, anti-inflammatory and antiproliferative properties. The compound differentially suppresses the growth of numerous human cancer cells and also inhibits tumor promoter-mediated processes in transformed cells (53,54). In transformed cells, CAPE induces apoptosis and inhibits the expression of the malignant phenotype (55,56). In addition, CAPE treatment attenuates the formation of azoxymethane-induced aberrant crypts and the activities of ornithine decarboxylase (ODC), tyrosin protein kinase, and lipoxygenase activity (57). Although the molecular basis for these multiple chemopreventive effects of CAPE is not clear, recent studies have demonstrated that CAPE is a potent and specific inhibitor of the transcription factor NF-kB (58). CAPE inhibited the activity and expression of COX-2 in the carrageenan air pouch model of inflammation as well as in TPA-treated human oral epithelial cells (59). CAPE was able to reduce neointimal formation by inhibiting NF-kB activation in a model of endothelial injury of rat carotid artery (60). 

Chemopreventive Properties of Fruit Phenolic Compounds and Their Possible Mode of Actions... 

Six main common chemopreventive effects that phenolic compounds can exert on cancer cells are (1) antioxidant effect, (2) antiproliferation effect, (3) induction of cell-cycle arrest, (4) induction of apoptosis, (5) antiinflammatory effect, and (6) inhibition of angiogenesis and metastasis (Table 2). 

Polyphenols are considered secondary metabolites of plants involved in the chemical defense of plants against predators and in plant-plant interactions. Polyphenols are found in virtually all families of plants, and comprise up to 50% of the dry weight of leaves. The main activity related to phenolic compounds is antioxidant activity. In addition to their strong antioxidant activities, plant polyphenols are known to possess other activities including antibacterial, chemopreventive, UV-protective, anticancer, and anti-inflammatory effects, act as detoxifying agents against heavy metals, and have myriad other bioactivities that could potentially be exploited for application in functional foods. ... 

Gerhauser C, Alt A, Klimo K, Knauft J, Frank N, Becker H (2002) Isolation and potential cancer chemopreventive activities of phenolic compounds of beer. Phytochem Rev... 

The predominant effect of flavonoid and isoflavonoid supplementation in ex vivo cell culture models appears to be one of promoting apoptosis [54—57]. This is repeatedly observed in studies witti transformed cancer cells, leading to the descriptions cytoprotective and/or chemopreventive [6,58]. Two poly-phenolic compounds that have been extensively studied in anticancer research are quercetin and genistein, a flavonoid and isoflavone, respectively. However, ex vivo studies with primary cultured cells in 2000 and 2001 showed that some flavonoids can prevent apoptosis promoted by agents that induce oxidative stress [7,8,59]. The outcome of flavonoid treatment is expected to show a complex dependence on a number of factors, including the type of flavonoid, its concentration, the type of cell (e.g., transformed versus nontransformed), the mechanisms of action of the flavonoid, the nature of the proapoptotic stimulus, and the specific apoptotic signaling pathway that is activated. 

The content of phenolic compounds is also of interest from the standpoint of chemoprevention. With 84 mg/g gallic acid equivalents (GAE) and... 

Extracts of sweet maijoram have antioxidant/ free radical scavenging properties that are in part due to labiatic, ursolic and camosic acids, and camosol and phenolic compounds. The antioxidant activity is reflected in the ability of the volatile oil and different maijoram extracts to act as liver and kidney chemopreventive agents against lead acetate toxicity in mice. ... 

Chemoprevention is a strategy used to block or suppress carcinogenesis and degenerative disease using dietary or pharmacological compounds. These chemo-preventive compounds include phenols [such as tm-butyl 4-hydroxyanisole (BHA), t-BHQ (active metabolite of BHA), ethoxyquine, curcumin (from turmeric) and resveratrol (from grapes)] and sulfur compounds [such as oltiplaz, sulforaphane... 

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