Green Tea Polyphenols Inhibit Colorectal Tumorigenesis in Azoxymethane-Treated F344 Rats.
In studying the cancer-preventive activities of green tea polyphenols, we previously demonstrated that dietary administration of polyphenon E (PPE) inhibited the formation of aberrant crypt foci (ACF) in the colon of azoxymethane (AOM)-treated F344 rats. Herein, we reported cancer-preventive activity of PPE using colorectal cancer as an end point. F344 rats were given two weekly injections of AOM, and then maintained on a 20% high-fat diet with or without 0.24% PPE for 34 wk. In the control group, 83% of rats developed colorectal tumors. Dietary PPE treatment significantly increased the plasma and colonic levels of tea polyphenols, and decreased tumor multiplicity and tumor size. Histological analysis indicated that PPE significantly decreased the incidence of adenocarcinoma, and the multiplicity of adenocarcinoma as well as the multiplicity of adenoma. PPE treatment significantly decreased plasma levels of proinflammatory eicosanoids, prostaglandin E2, and leukotriene B4. It also decreased β-catenin nuclear expression, induced apoptosis, and increased expression levels of RXRα, β, and γ in adenocarcinomas. In conclusion, our results convincingly demonstrated the inhibitory effects of orally administered PPE on colon carcinogenesis in AOM-treated rats and suggested possible biomarkers for the biological effects of green tea polyphenols.
a Susan Lehman Cullman Laboratory for Cancer Research, Department of Chemical Biology , Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey , Piscataway , New Jersey , USA.|b Pathology and Histotechnology Laboratory , Leidos Biomedical Research Institute Inc., Frederick National Laboratory for Cancer Research , Frederick , Maryland , USA.
Xingpei
X
Hao
a Susan Lehman Cullman Laboratory for Cancer Research, Department of Chemical Biology , Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey , Piscataway , New Jersey , USA.|c Department of Food Science , University of Massachusetts , Amherst , Massachusetts , USA.
Hang
H
Xiao
a Susan Lehman Cullman Laboratory for Cancer Research, Department of Chemical Biology , Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey , Piscataway , New Jersey , USA.|d Department of Food and Nutrition , Chungbuk National University , Cheongju , Chungbuk , Korea.
Jihyeung
J
Ju
a Susan Lehman Cullman Laboratory for Cancer Research, Department of Chemical Biology , Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey , Piscataway , New Jersey , USA.
Mao-Jung
MJ
Lee
a Susan Lehman Cullman Laboratory for Cancer Research, Department of Chemical Biology , Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey , Piscataway , New Jersey , USA.|e Department of Food Science , Center for Molecular Toxicology and Carcinogenesis, The Pennsylvania State University , University Park , Pennsylvania , USA.
Joshua D
JD
Lambert
a Susan Lehman Cullman Laboratory for Cancer Research, Department of Chemical Biology , Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey , Piscataway , New Jersey , USA.
Chung S
CS
Yang
D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D001397:Azoxymethane / Q000633:toxicity; D002392:Catechin / Q000031:analogs & derivatives / Q000097:blood / Q000378:metabolism / Q000494:pharmacology; D015179:Colorectal Neoplasms / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control*; D019587:Dietary Supplements; D015232:Dinoprostone / Q000378:metabolism; D007975:Leukotriene B4 / Q000378:metabolism; D008297:Male; D009374:Neoplasms, Experimental / Q000188:drug therapy / Q000473:pathology; D059808:Polyphenols / Q000494:pharmacology*; D011916:Rats, Inbred F344; D047488:Retinoid X Receptors / Q000378:metabolism; D013662:Tea / Q000737:chemistry*; D051176:beta Catenin / Q000378:metabolism
D000972:Antineoplastic Agents, Phytogenic; C495268:Ctnnb1 protein, rat; D059808:Polyphenols; D047488:Retinoid X Receptors; D013662:Tea; D051176:beta Catenin; D007975:Leukotriene B4; D002392:Catechin; D015232:Dinoprostone; D001397:Azoxymethane; C472086:polyphenon E