title: Lycopene supplementation prevents smoke-induced changes in p53, p53 phosphorylation, cell proliferation, and apoptosis in the gastric mucosa of ferrets.
abstract: Cigarette smoking increases the risk for gastric cancer. Higher intakes or blood levels of lycopene are associated with a decreased risk of gastric cancer. However, the biological mechanisms by which lycopene may protect against gastric carcinogenesis are poorly understood. We evaluated the effects of lycopene supplementation on smoke-induced changes in protein levels of p53, p53 target genes (p21(Waf1/Cip1) and Bax-1), cell proliferation, and apoptosis in the gastric mucosa of ferrets. Ferrets were assigned to cigarette smoke exposure or to no exposure and to no, low-dose, or high-dose lycopene supplementation (2 x 3 factorial design) for 9 wk. Lycopene concentrations were significantly elevated in a dose-dependent manner in the gastric mucosa of ferrets supplemented with lycopene alone, but were markedly reduced in ferrets supplemented with lycopene and exposed to smoke. Although ferrets were given lycopene containing 95% all-trans isomers, cis isomers were the predominant forms in the gastric mucosa. Total p53 and phosphorylated p53 levels were greater in ferrets exposed to smoke alone than in all other groups. Levels were approximately 300 and 500% of the controls, respectively. However, smoke-elevated total p53 and phosphorylated p53 were markedly attenuated by both doses of lycopene. p21(Waf1/Cip1), Bax-1, and cleaved caspase 3 were substantially decreased, whereas cyclin D1 and proliferating cellular nuclear antigen (PCNA) were increased in ferrets exposed to smoke alone. Lycopene prevented smoke-induced changes in p21(Waf1/Cip1), Bax-1, cleaved caspase 3, cyclin D1, and PCNA in a dose-dependent fashion. These data indicate that lycopene may prevent smoke exposure-induced changes in p53, p53 phosphorylation, p53 target genes, cell proliferation, and apoptosis in the gastric mucosa of ferrets.
authors.affiliation: Nutrition and Cancer Biology Laboratory, Jean Mayer United States Department of Agriculture Human Nutrition Research Center on Aging at Tufts University, Boston, MA, USA. chun.liu@tufts.edu
authors.forename: Chun
authors.initials: C
authors.lastname: Liu
authors.forename: Robert M
authors.initials: RM
authors.lastname: Russell
authors.forename: Xiang-Dong
authors.initials: XD
authors.lastname: Wang
mesh_terms: D000818:Animals; D016588:Anticarcinogenic Agents / Q000378:metabolism / Q000627:therapeutic use*; D017209:Apoptosis / Q000187:drug effects*; D002338:Carotenoids / Q000378:metabolism / Q000627:therapeutic use*; D049109:Cell Proliferation / Q000187:drug effects*; D005289:Ferrets; D005753:Gastric Mucosa / Q000187:drug effects* / Q000378:metabolism; D016158:Genes, p53 / Q000187:drug effects; D000077276:Lycopene; D008297:Male; D010766:Phosphorylation / Q000187:drug effects; D012906:Smoke / Q000009:adverse effects*; D013274:Stomach Neoplasms / Q000517:prevention & control*
chemical_list: D016588:Anticarcinogenic Agents; D012906:Smoke; D002338:Carotenoids; D000077276:Lycopene