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Antioxidant micronutrients may have chemopreventive effects. The authors examined the associations between prediagnostic blood levels of micronutrients and prostate cancer risk in two nested case-control studies of 9,804 and 10,456 male residents of Washington County, Maryland, who donated blood in 1974 (CLUE I) and 1989 (CLUE II), respectively. Until 1996, 182 men for whom adequate serum remained for assays in the CLUE I cohort and 142 men in the CLUE II cohort developed prostate cancer. Each case was matched with two controls by age, gender, race, and date of blood donation. In both cohorts, cases and controls had similar concentrations of α-carotene, β-carotene, total carotene, β-cryptoxanthin, lutein, lycopene, retinol, and ascorbic acid; serum α-tocopherol was weakly associated with prostate cancer risk. Higher retinyl palmitate concentrations were associated with a lower risk in CLUE I but not CLUE II. In CLUE I, cases had lower concentrations of γ-tocopherol than did controls (p = 0.02), but no dose-response trend was observed. A strong inverse association between γ-tocopherol and prostate cancer risk was observed in CLUE II. Findings do not replicate previous reports of a protective association between lycopene and prostate cancer, but they suggest potential chemopreventive effects of γ-tocopherol on prostate cancer. [ABSTRACT FROM PUBLISHER]

The purpose of this study was to examine the associations between single nucleotide polymorphisms (SNPs) in genes controlling inflammatory processes and mortality. Data were analyzed from 9,933 individuals who participated in two large community-based cohort studies conducted in Washington County, Maryland, in 1974 and 1989, designated “CLUE I” and “CLUE II,” respectively. DNA from blood collected in 1989 was genotyped for 47 SNPs in 23 inflammation-related genes, including interferon-γ (IFNγ), lymphotoxin-α (LTα), tumor necrosis factor-α (TNFα), C-reactive protein (CRP), peroxisome proliferator-activated receptor (PPAR), and the human endothelial nitric oxide synthase (eNOS). All participants were followed from 1989 to the date of death or to June 20, 2005. The results showed no observable patterns of association for the SNPs and the all-cause and cause-specific mortality outcomes, although statistically significant associations were observed between at least one mortality outcome and SNPs in eNOS (reference SNP (rs) 1799983), PPARG (rs4684847), CRP (rs2794521), IFNγ (rs2069705), TNFα (rs1799964), and LTα (rs2229094). Additionally, three of the four examined CRP SNPs were strongly associated with CRP serum concentration among those with CRP measurements. The authors findings from this community-based prospective cohort study suggest that the selected SNPs are not associated with overall or cause-specific death, although CRP genotypes may be associated with systemic inflammation. [ABSTRACT FROM AUTHOR]

Lung cancer cases diagnosed during the period 1975 through 1993 and matched controls were identified in the rosters of Washington County, Maryland residents who had donated blood for a serum bank in 1974 or 1989. Plasma from participants in the 1989 project was assayed for ascorbic acid; serum or plasma was assayed for participants in either project for alpha- and beta-carotene, cryptoxanthin, lutein/zeaxanthin, lycopene, alpha-tocopherol, selenium, and peroxyl radical absorption capacity. Among the total group of 258 cases and 515 controls, serum/plasma concentrations were significantly lower among cases than controls for cryptoxanthin, beta-carotene, and lutein/zeaxanthin with case-control differences of -25.5, -17.1, and -10.1%, respectively. Modest nonsignificant case-control differences in a protective direction were noted for alpha-carotene and ascorbic acid. There were only trivial differences for lycopene, alpha-tocopherol, selenium, and peroxyl radical absorption capacity. Findings are reported for males and females and for persons who had never smoked cigarettes, former smokers, and current smokers at baseline. These results and those from previous studies suggest that beta-carotene is a marker for some protective factor(s) against lung cancer; that cryptoxanthin, alpha-carotene, and ascorbic acid need to be investigated further as potentially protective factors or associates of a protective factor; and that lycopene, alpha-tocopherol, selenium, and peroxyl radical absorption capacity are unlikely to be associated with lung cancer risk. Until specific preventive factors are identified, the best protection against lung cancer is still the avoidance of airborne carcinogens, especially tobacco smoke; second best is the consumption of a diet rich in fruits and vegetables.