Efficacy of Polyphenon E, Red Ginseng, and Rapamycin on Benzo(a)pyrene-Induced Lung Tumorigenesis in A/J Mice

Abstract

The objective of this investigation was to determine the efficacy of several novel agents in preventing lung tumorigenesis in mice. We evaluated polyphenon E, red ginseng, and rapamycin in A/J mice treated with the tobacco-specific carcinogen benzo(a)pyrene for their ability to inhibit pulmonary adenoma formation and growth. We found that treatment with polyphenon E exhibited a significant reduction on both tumor multiplicity and tumor load (tumor multiplicity × tumor volume) in a dose-dependent fashion. Polyphenon E (2% wt/wt) in the diet reduced tumor multiplicity by 46% and tumor load by 94%. This result provided key evidence in support of a phase II clinical chemoprevention trial of lung cancer. Administration of red ginseng in drinking water decreased tumor multiplicity by 36% and tumor load by 70%. The mammalian target of rapamycin inhibitor rapamycin showed significant efficacy against lung tumor growth in the tumor progression protocol and reduced tumor load by 84%. The results of these investigations demonstrate that polyphenon E, red ginseng, and rapamycin significantly inhibit pulmonary adenoma formation and growth in A/J mice.