title: Gastric cancer in Zambian adults: a prospective case-control study that assessed dietary intake and antioxidant status by using urinary isoprostane excretion.
abstract: BACKGROUND
  Gastric cancer is increasingly recognized in Zambia. Although nutritional factors contribute to gastric cancer risk, their effect in Zambia is unknown.
  
  
  OBJECTIVE
  The objective was to investigate the association between intake of dietary antioxidants, urinary 8-iso prostaglandin F2α (8-iso PGF2α) as a marker of oxidative stress, and gastric cancer.
  
  
  METHODS
  This was a case-control study at the University Teaching Hospital in Zambia. Gastric cancer cases were compared with age- and sex-matched controls. Urine 8-iso PGF2α was measured primarily by ELISA, and by gas chromatography-mass spectrometry in a subset, expressed as a ratio to creatinine. Blood was collected for Helicobacter pylori, HIV serology, gastrin-17, and pepsinogen 1 and 2 concentrations. Clinical and dietary data were collected by using questionnaires. Food items were broadly classified into 7 major categories (fruit, vegetables, fish, meat, insects, cereals, and starches).
  
  
  RESULTS
  Fifty cases with gastric cancer (mean age: 61 y; n = 31 males) and 90 controls (mean age: 54 y; n = 41 males) were enrolled. Median urinary 8-iso PGF2α excretion was higher in cases (0.014; IQR: 0.008-0.021) than in controls (0.011; IQR: 0.006-0.018; P = 0.039). On univariate analysis, habitual fruit intake was lower in cases than in controls during the dry season (P = 0.02). On multivariate analysis, smoking (OR: 7.22; IQR: 1.38-37.9) and gastric atrophy (OR: 2.43; IQR: 1.12-5.13) were independently associated with cancer, and higher fruit intake was protective (OR: 0.44; IQR: 0.20-0.95). Isoprostane excretion was inversely correlated with total fruit intake (ρ = -0.23; n = 140; P = 0.006).
  
  
  CONCLUSIONS
  Urinary 8-iso PGF2α excretion was associated with the risk of gastric cancer, as were smoking and gastric atrophy, but increased fruit intake conferred protection. This trial was registered at www.pactr.org as ISRCTN52971746.
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, University of Zambia School of Medicine, University Teaching Hospital, Lusaka, Zambia.
authors.forename: Akwi W
authors.initials: AW
authors.lastname: Asombang
authors.forename: Violet
authors.initials: V
authors.lastname: Kayamba
authors.forename: Mpala
authors.initials: M
authors.lastname: Mwanza-Lisulo
authors.forename: Graham
authors.initials: G
authors.lastname: Colditz
authors.forename: Victor
authors.initials: V
authors.lastname: Mudenda
authors.forename: Kevin
authors.initials: K
authors.lastname: Yarasheski
authors.forename: Robert
authors.initials: R
authors.lastname: Chott
authors.forename: Deborah C
authors.initials: DC
authors.lastname: Rubin
authors.forename: C Prakash
authors.initials: CP
authors.lastname: Gyawali
authors.forename: Edford
authors.initials: E
authors.lastname: Sinkala
authors.forename: Stayner
authors.initials: S
authors.lastname: Mwanamakondo
authors.forename: Catherine
authors.initials: C
authors.lastname: Anderson-Spearie
authors.forename: Paul
authors.initials: P
authors.lastname: Kelly
mesh_terms: D000328:Adult; D000975:Antioxidants / Q000008:administration & dosage*; D015415:Biomarkers / Q000097:blood / Q000652:urine; D016022:Case-Control Studies; D003404:Creatinine / Q000652:urine; D015237:Dinoprost / Q000031:analogs & derivatives / Q000652:urine; D002149:Energy Intake; D005247:Feeding Behavior; D005260:Female; D005638:Fruit; D008401:Gas Chromatography-Mass Spectrometry; D005755:Gastrins / Q000097:blood; D006678:HIV / Q000302:isolation & purification; D016480:Helicobacter pylori / Q000302:isolation & purification; D006801:Humans; D028421:Isoprostanes / Q000652:urine*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009752:Nutritional Status; D018384:Oxidative Stress / Q000187:drug effects; D020116:Pepsinogen A / Q000097:blood; D020115:Pepsinogen C / Q000097:blood; D011446:Prospective Studies; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects; D013274:Stomach Neoplasms / Q000453:epidemiology*; D011795:Surveys and Questionnaires; D014675:Vegetables; D015024:Zambia / Q000453:epidemiology
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D005755:Gastrins; D028421:Isoprostanes; C075750:8-epi-prostaglandin F2alpha; C013550:gastrin 17; D020115:Pepsinogen C; D020116:Pepsinogen A; D003404:Creatinine; D015237:Dinoprost
references.citation: Exp Physiol. 1997 Mar;82(2):291-5
references.pmid: 9129943
references.citation: Cancer Epidemiol Biomarkers Prev. 2009 Jul;18(7):1962-70
references.pmid: 19531680
references.citation: Acta Pathol Microbiol Scand. 1965;64:31-49
references.pmid: 14320675
references.citation: Methods Enzymol. 2007;433:113-26
references.pmid: 17954231
references.citation: FASEB J. 2004 Dec;18(15):1791-800
references.pmid: 15576482
references.citation: Cancer Res. 1988 Jul 1;48(13):3554-60
references.pmid: 3288329
references.citation: IARC Sci Publ. 2004;(157):311-26
references.pmid: 15055304
references.citation: Am J Epidemiol. 2000 Mar 1;151(5):531-9
references.pmid: 10707923
references.citation: Trans R Soc Trop Med Hyg. 2008 Feb;102(2):194-9
references.pmid: 18054058
references.citation: Trans R Soc Trop Med Hyg. 2012 Feb;106(2):69-74
references.pmid: 22136952
references.citation: J Womens Health (Larchmt). 2009 Sep;18(9):1449-56
references.pmid: 19708802
references.citation: Int J Cancer. 2012 Dec 15;131(12):2910-9
references.pmid: 22473701
references.citation: J Urol. 2011 Jun;185(6):2102-7
references.pmid: 21496850
references.citation: Mol Aspects Med. 1994;15(4):293-376
references.pmid: 7845187
references.citation: J Am Diet Assoc. 2009 Mar;109(3):414-21
references.pmid: 19248856
references.citation: Dig Dis Sci. 2009 Dec;54(12):2629-33
references.pmid: 19093202
references.citation: J Clin Microbiol. 2001 Apr;39(4):1323-7
references.pmid: 11283050
references.citation: Integr Cancer Ther. 2007 Dec;6(4):365-72
references.pmid: 18048884
references.citation: Free Radic Biol Med. 2007 Oct 15;43(8):1109-20
references.pmid: 17854706
references.citation: Afr Health Sci. 2005 Sep;5(3):234-7
references.pmid: 16245994