title: Smoking, green tea consumption, genetic polymorphisms in the insulin-like growth factors and lung cancer risk.
abstract: Insulin-like growth factors (IGFs) are mediators of growth hormones; they have an influence on cell proliferation and differentiation. In addition, IGF-binding protein (IGFBP)-3 could suppress the mitogenic action of IGFs. Interestingly, tea polyphenols could substantially reduce IGF1 and increase IGFBP3. In this study, we evaluated the effects of smoking, green tea consumption, as well as IGF1, IGF2, and IGFBP3 polymorphisms, on lung cancer risk. Questionnaires were administered to obtain the subjects' characteristics, including smoking habits and green tea consumption from 170 primary lung cancer cases and 340 healthy controls. Genotypes for IGF1, IGF2, and IGFBP3 were identified by polymerase chain reaction. Lung cancer cases had a higher proportion of smoking, green tea consumption of less than one cup per day, exposure to cooking fumes, and family history of lung cancer than controls. After adjusting the confounding effect, an elevated risk was observed in smokers who never drank green tea, as compared to smokers who drank green tea more than one cup per day (odds ratio (OR) = 13.16, 95% confidence interval (CI) = 2.96-58.51). Interaction between smoking and green tea consumption on lung cancer risk was also observed. Among green tea drinkers who drank more than one cup per day, IGF1 (CA)(19)/(CA)(19) and (CA)(19)/X genotypes carriers had a significantly reduced risk of lung cancer (OR = 0.06, 95% CI = 0.01-0.44) compared with IGF1 X/X carriers. Smoking-induced pulmonary carcinogenesis could be modulated by green tea consumption and their growth factor environment.
authors.affiliation: Institute of Public Health, Chung Shan Medical University, Taichung, Taiwan.
authors.forename: I-Hsin
authors.initials: IH
authors.lastname: Lin
authors.forename: Ming-Lin
authors.initials: ML
authors.lastname: Ho
authors.forename: Hsuan-Yu
authors.initials: HY
authors.lastname: Chen
authors.forename: Hong-Shen
authors.initials: HS
authors.lastname: Lee
authors.forename: Chia-Chen
authors.initials: CC
authors.lastname: Huang
authors.forename: Yin-Hung
authors.initials: YH
authors.lastname: Chu
authors.forename: Shiau-Yun
authors.initials: SY
authors.lastname: Lin
authors.forename: Ya-Ru
authors.initials: YR
authors.lastname: Deng
authors.forename: Yu-Hao
authors.initials: YH
authors.lastname: He
authors.forename: Yu-Hui
authors.initials: YH
authors.lastname: Lien
authors.forename: Chi-Wen
authors.initials: CW
authors.lastname: Hsu
authors.forename: Ruey-Hong
authors.initials: RH
authors.lastname: Wong
mesh_terms: D017677:Age Distribution; D000368:Aged; D016022:Case-Control Studies; D041321:Chromosomes, Human, X; D005260:Female; D005838:Genotype; D006579:Heterozygote; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000235:genetics; D007334:Insulin-Like Growth Factor I / Q000235:genetics; D007335:Insulin-Like Growth Factor II / Q000235:genetics; D008175:Lung Neoplasms / Q000453:epidemiology / Q000209:etiology* / Q000235:genetics; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D012306:Risk; D012907:Smoking / Q000009:adverse effects*; D013002:Somatomedins / Q000235:genetics*; D011795:Surveys and Questionnaires; D013662:Tea
chemical_list: D018972:Insulin-Like Growth Factor Binding Protein 3; D013002:Somatomedins; D013662:Tea; D007334:Insulin-Like Growth Factor I; D007335:Insulin-Like Growth Factor II