title: Prospective study of serum cysteine and cysteinylglycine and cancer of the head and neck, esophagus, and stomach in a cohort of male smokers.
abstract: BACKGROUND
  The nonessential amino acid cysteine is known to be involved in many antioxidant and anticarcinogenic pathways. Cysteinylglycine is a pro-oxidant metabolite of glutathione and a precursor of cysteine.
  
  
  OBJECTIVE
  To examine the relation between serum cysteine and cysteinylglycine and risk of gastric adenocarcinomas, esophageal squamous cell carcinomas, and head and neck squamous cell carcinomas, we conducted a nested case-control study within the Alpha-Tocopherol, Beta-Carotene Cancer Prevention study of male Finnish smokers aged 50-69 y at baseline.
  
  
  METHODS
  In total, 170 gastric adenocarcinomas, 68 esophageal squamous cell carcinomas, and 270 head and neck squamous cell carcinomas (identified from the Finnish Cancer Registry) were matched one-to-one with cancer-free control subjects on age and the date of serum collection. We calculated ORs and 95% CIs with the use of a multivariate-adjusted conditional logistic regression.
  
  
  RESULTS
  Cysteine had a U-shaped association with gastric adenocarcinomas; a model that included a linear and a squared term had a significant global P-test (P = 0.036). Serum cysteinylglycine was inversely associated with adenocarcinomas of the gastric cardia (OR for above the median compared with below the median: 0.07; 95% CI: 0.01, 0.70; n = 38 cases) but not for other sites. Both cysteine and cysteinylglycine were not associated with esophageal squamous cell carcinoma or head and neck squamous cell carcinoma.
  
  
  CONCLUSIONS
  We observed associations between serum cysteine and cysteinylglycine with upper gastrointestinal cancer risk. Future studies are needed to replicate these findings. This trial was registered at clininicaltrials.gov as NCT00342992.
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Department of Health and Human Services, Rockville, MD;
authors.forename: Eugenia H
authors.initials: EH
authors.lastname: Miranti
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Department of Health and Human Services, Rockville, MD; freedmanne@mail.nih.gov.
authors.forename: Neal D
authors.initials: ND
authors.lastname: Freedman
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Department of Health and Human Services, Rockville, MD;
authors.forename: Stephanie J
authors.initials: SJ
authors.lastname: Weinstein
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Department of Health and Human Services, Rockville, MD;
authors.forename: Christian C
authors.initials: CC
authors.lastname: Abnet
authors.affiliation: Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, MA;
authors.forename: Jacob
authors.initials: J
authors.lastname: Selhub
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Department of Health and Human Services, Rockville, MD;
authors.forename: Gwen
authors.initials: G
authors.lastname: Murphy
authors.affiliation: Pulmonary and Vascular Medicine Branch, National Heart Lung and Blood Institute, NIH, Department of Health and Human Services, Bethesda, MD; and.
authors.forename: Lena
authors.initials: L
authors.lastname: Diaw
authors.affiliation: Department of Chronic Disease Prevention, National Institute for Health and Welfare, Helsinki, Finland.
authors.forename: Satu
authors.initials: S
authors.lastname: Männistö
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Department of Health and Human Services, Rockville, MD;
authors.forename: Philip R
authors.initials: PR
authors.lastname: Taylor
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Department of Health and Human Services, Rockville, MD;
authors.forename: Demetrius
authors.initials: D
authors.lastname: Albanes
authors.affiliation: Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Department of Health and Human Services, Rockville, MD;
authors.forename: Rachael Z
authors.initials: RZ
authors.lastname: Stolzenberg-Solomon
mesh_terms: D000230:Adenocarcinoma / Q000097:blood / Q000453:epidemiology / Q000209:etiology* / Q000517:prevention & control; D000975:Antioxidants / Q000627:therapeutic use; D015415:Biomarkers / Q000097:blood; D002294:Carcinoma, Squamous Cell / Q000097:blood / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control; D016022:Case-Control Studies; D015331:Cohort Studies; D003545:Cysteine / Q000097:blood* / Q000172:deficiency; D003677:Deficiency Diseases / Q000209:etiology / Q000503:physiopathology*; D019587:Dietary Supplements; D004151:Dipeptides / Q000097:blood*; D005387:Finland / Q000453:epidemiology; D006258:Head and Neck Neoplasms / Q000097:blood / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control; D006801:Humans; D020138:Hyperhomocysteinemia / Q000209:etiology / Q000503:physiopathology*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress; D011446:Prospective Studies; D016032:Randomized Controlled Trials as Topic; D012042:Registries; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects*; D013274:Stomach Neoplasms / Q000097:blood / Q000453:epidemiology / Q000209:etiology* / Q000517:prevention & control
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D004151:Dipeptides; C028505:cysteinylglycine; D003545:Cysteine
keywords: cysteine; esophageal neoplasms; head and neck neoplasms; stomach neoplasms; upper gastrointestinal tract cancers