title: Oxidant stress and glioblastoma multiforme risk: serum antioxidants, gamma-glutamyl transpeptidase, and ferritin.
abstract: Case-control studies of serum antioxidants are difficult to interpret, because antioxidants may be altered by the disease under study. However, because glioblastoma multiforme (GBM) is a relatively rare disease, a cohort study would require a large sample observed for many years. In the present case-control pilot study (34 cases and 35 controls), we evaluated the association between serum levels of ascorbic acid (AA) and alpha- and gamma-tocopherol (alpha-T and gamma-T) measured before diagnostic surgery. To control for influence of GBM on serum AA, alpha-T, and gamma-T, we adjusted for oxidant stress indexes (gamma-glutamyl transpeptidase and uric acid) and an acute-phase response index (serum ferritin). When adjusted, AA is inversely related to GBM (p for trend = 0.007). In addition, AA interacts with alpha-T to further reduce GBM risk (test for interaction, p = 0.04). gamma-T is not associated with GBM (p = 0.71). However, gamma-glutamyl transpeptidase (p = 0.004), coenzyme Q (p = 0.01), and ferritin (p = 0.009) are positively and uric acid (p = 0.000) is negatively related to GBM. We conclude that 1) AA and alpha-T are jointly related to GBM after adjustment for GBM-produced oxidant stress and 2) there is a strong association between the presence of GBM and oxidant stress.
authors.affiliation: Division of Epidemiology and Biometrics, College of Medicine and Public Health, Ohio State University, and Comprehensive Cancer Center, Columbus, OH 43210, USA.
authors.forename: J A
authors.initials: JA
authors.lastname: Schwartzbaum
authors.forename: D G
authors.initials: DG
authors.lastname: Cornwell
mesh_terms: D000210:Acute-Phase Reaction; D000368:Aged; D000975:Antioxidants / Q000032:analysis*; D001205:Ascorbic Acid / Q000097:blood; D001932:Brain Neoplasms / Q000097:blood / Q000201:enzymology / Q000209:etiology*; D016022:Case-Control Studies; D005260:Female; D005293:Ferritins / Q000097:blood; D005909:Glioblastoma / Q000097:blood / Q000201:enzymology / Q000209:etiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress; D010865:Pilot Projects; D012307:Risk Factors; D014451:Ubiquinone / Q000097:blood; D014527:Uric Acid / Q000097:blood; D024502:alpha-Tocopherol / Q000097:blood; D005723:gamma-Glutamyltransferase / Q000097:blood; D024504:gamma-Tocopherol / Q000097:blood
chemical_list: D000975:Antioxidants; D014451:Ubiquinone; D014527:Uric Acid; D024504:gamma-Tocopherol; D005293:Ferritins; D005723:gamma-Glutamyltransferase; D024502:alpha-Tocopherol; D001205:Ascorbic Acid