Association Between alpha-Tocopherol, gamma-Tocopherol, Selenium, and Subsequent Prostate Cancer

Helzlsouer, Kathy J.; Huang, Han-Yao; Alberg, Anthony J.; Hoffman, Sandra C.; Burke, Alyce; Norkus, Edward P.; Morris, J. Steven; Comstock, George W.

doi:10.1093/jnci/92.24.2018

Cited by 353 publications

(208 citation statements)

References 16 publications

Supporting

Mentioning

190

Contrasting

Unclassified

Order By: Relevance

“…Although previous studies have assessed the selenium content in toe nails, which is 9 -15% lower than that of fingernails (Baskett et al, 1995), selenium concentrations in these British men are still somewhat lower than those reported in North American populations (Yoshizawa et al, 1998;Ghadirian et al, 2000;Helzlsouer et al, 2000) and are comparable with other European populations (Kardinaal et al, 1997;van den Brandt et al, 2003). It is well established that the selenium content of European soils is low and that dietary intake has been gradually declining due to a reduction in imported selenium-rich wheat from the US and Canada, together with a general decline in cereal consumption (Rayman, 1997).…”

Section: Discussionmentioning

confidence: 75%

A case–control study of selenium in nails and prostate cancer risk in British men

et al. 2004

View full text Add to dashboard Cite

In view of the experimental evidence suggesting that the micronutrient selenium reduces prostate cancer risk, we investigated the association between the selenium level in fingernails, a measure of long-term selenium intake, and prostate cancer risk in a case -control study among 656 British men, conducted in 1989British men, conducted in -1992. Nail clippings were taken at the time of recruitment and selenium concentration, measured using neutron activation techniques, was successfully assayed for 300 case -control pairs and varied six-fold among the controls (0.59 p.p.m.; interquartile range, 0.50 -0.71 p.p.m.). Nail selenium concentration was not significantly associated with prostate cancer risk: men in the highest quartile of nail selenium had a slightly increased risk compared with men in the lowest quartile (OR 1.24, 95 CI, 0.73 -2.10); for advanced prostate cancer, men in the highest quartile had a slightly reduced risk compared with men in the lowest quartile (OR 0.78, 95% CI, Selenium is an essential trace element found largely in grains, fish and meat products and has been shown to have antioxidant and other potentially anticarcinogenic properties (Combs and Gray, 1998). Experimental evidence indicates that selenium supplementation can reduce the incidence of viral and chemically induced tumours in animals (Vernie, 1984), including prostate cancer cell lines (Menter et al, 2000).The selenium content in foods varies widely between regions (Levander, 1987) because it is largely determined by the amount of selenium in the soil. Ecological data suggest that regional cancer mortality rates in the United States are inversely correlated with the selenium concentration in plants (Clark et al, 1991), and a randomised controlled trial among skin cancer patients found selenium supplementation of 200 mg day À1 to be associated with a significant 63% reduction in prostate cancer incidence (Clark et al, 1996;Duffield-Lillico et al, 2002). However, little is known about the relationship between the selenium status and prostate cancer risk in the general population.The aim of this study is to investigate the association between nail selenium concentration, a marker of long-term intake, and prostate cancer risk. A subsidiary aim is to examine whether factors that may influence selenium status, such as smoking (Hunter et al, 1990), vitamin E intake (Diplock, 1978) or the aggressiveness of disease at the time of recruitment (Yoshizawa et al, 1998;Goodman et al, 2001) modify the association between selenium concentration and prostate cancer risk. SUBJECTS AND METHODSA population-based case -control study of the association between diet and prostate cancer was established in Britain, between 1989 and 1992, and included 328 men with incident prostate cancer and 328 population-based controls (Key et al, 1997). The study was restricted to white men under the age of 75 years who could speak English and who were well enough to complete a diet interview and give a reasonable history. Identification of cases was by searching a...

show abstract

Section: Discussionmentioning

confidence: 75%

A case–control study of selenium in nails and prostate cancer risk in British men

et al. 2004

View full text Add to dashboard Cite

show abstract

“…As shown in Figure 1, all three alleles coding for five, six or seven alanines in the polyalanine track (Ala5, Ala6, Ala7) occur with a frequency of 49, 29 and 24% respectively and about 70% of genotypes are heterozygous in the European CEPH sample set. 6 Genotyping results are shown in Table 1. We found no significant association between the GPX1 genotypes and the risk of young onset prostate cancer (w 2 5 ¼ 2.64; P ¼ 0.12).…”

Section: Resultsmentioning

confidence: 99%

“…Human cellular glutathione peroxidase I (hGPX1) is a selenium dependent antioxidant enzyme and the gene, GPX1 maps to 3p21. 6 In addition to an informative trinucleotide repeat polymorphism that has been genotyped in our study, three other common single nucleotide polymorphisms (SNPs) have been identified: a leucine to proline substitution at codon 198 (C > T at 593) and two further base changes in the non-coding region (C > T at þ 2 and G > A at 7 592). These three polymorphisms are in complete linkage disequilibrium with the Ala6 repeat, therefore this allele is the most likely to be functionally distinct.…”

Section: Discussionmentioning

confidence: 98%

“…So far, four studies have reported a significant reduction in risk for prostate cancer as the selenium intake increased. Two of them are based on the measurement of the long-term selenium intake using toe-nail clippings, 3,6 one is based on serum selenium measurements, 5 and one on selenium supplementation in a double-blinded study. 2 Three studies reported a reduction of risk for developing prostate cancer as the selenium level increased, suggesting that selenium can provide a two -three-fold protection against prostate cancer.…”

Section: Discussionmentioning

confidence: 99%

“…3 A large case -control study however failed to find a similar association between prostate cancer risk and toenail selenium, but the selenium level was inversely correlated with colon cancer risk. 4 Two recent reports also suggested the benefit of selenium in relation to incident prostate cancer, 5,6 however the association was mainly present in current or past cigarette smokers. 5 These findings provide some evidence for a possible protective role of selenium against the development of prostate cancer.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Association between the GCG polymorphism of the selenium dependent GPX1 gene and the risk of young onset prostate cancer

Kóte-Jarai

Durocher

Edwards

et al. 2002

Prostate Cancer Prostatic Dis

View full text Add to dashboard Cite

Epidemiological studies have suggested an association between low selenium levels and the development of prostate cancer. Human cellular glutathione peroxidase I (hGPX1) is a selenium-dependent enzyme that protects against oxidative damage and its peroxidase activity is a plausible mechanism for cancer prevention by selenium. The GPX1 gene has a GCG repeat polymorphism in exon 1, coding for a polyalanine tract of five to seven alanine residues. To test if the GPX1 GCG repeat polymorphism associates with the risk of young-onset prostate cancer we conducted a case -control study. The GPX1 Ala genotypes were determined for 267 prostate cancer cases and 260 control individuals using polymerase chain reaction (PCR) amplification with fluorescently labelled primers and an ABI 377 automated genotyper. Associations between specific genotypes and the risk of prostate cancer were examined by logistic regression. We found no significant association between the GPX1 genotypes and prostate cancer. There was however an increased frequency of the GPX1 Ala6/Ala6 genotype in the prostate cancer cases compared to controls (OR: 1.67; 95% CI: 0.97 -2.87). The result of this study suggests that the GPX1 genotype is unlikely to be associated with the risk of developing prostate cancer.

show abstract

Vitamins E and C in the Prevention of Prostate and Total Cancer in Men

Gaziano

Glynn²,

Christen³

et al. 2009

JAMA

455

134

View full text Add to dashboard Cite

Context Many Americans take vitamins in the hopes of preventing chronic diseases such as cancer, and vitamins E and C are among the most common individual supplements. A large-scale randomized trial suggested that vitamin E may reduce risk of prostate cancer; however, few trials have been powered to address this relationship. No previous trial in men at usual risk has examined vitamin C alone in the prevention of cancer. Objective To evaluate whether long-term vitamin E or C supplementation decreases risk of prostate and total cancer events among men. Design, Setting, and Participants The Physicians’ Health Study II is a randomized, double-blind, placebo-controlled factorial trial of vitamins E and C that began in 1997 and continued until its scheduled completion on August 31, 2007. A total of 14,641 male physicians in the U.S. initially aged ≥50 years, including 1,307 men with a history of prior cancer at randomization, were enrolled. Intervention Individual supplements of 400 IU of vitamin E every other day and 500 mg vitamin C daily. Main Outcome Measures Prostate and total cancer. Results During a mean follow-up of 8.0 years, there were 1,008 confirmed incident cases of prostate cancer and 1,943 total cancers. Compared with placebo, vitamin E had no effect on the incidence of prostate cancer (active and placebo vitamin E groups, 9.1 and 9.5 events per 1,000 person-years; hazard ratio [HR], 0.97; 95% confidence interval [CI], 0.85–1.09; P=0.58) or total cancer (active and placebo vitamin E groups, 17.8 and 17.3 cases per 1,000 person-years; HR, 1.04; 95% CI, 0.95–1.13; P=0.41). There was also no significant effect of vitamin C on total cancer (active and placebo vitamin C groups, 17.6 and 17.5 events per 1,000 person-years; HR, 1.01; 95% CI, 0.92–1.10; P=0.86), or prostate cancer (active and placebo vitamin C groups, 9.4 and 9.2 cases per 1,000 person-years; HR, 1.02; 95% CI, 0.90–1.15; P=0.80). Neither vitamin E nor vitamin C had a significant effect on colorectal, lung, or other site-specific cancers. Adjustment for compliance and exclusion of the first four or six years of follow-up did not alter the results. Stratification by various cancer risk factors demonstrated no significant modification of the effect of vitamin E on prostate cancer risk or either agent on total cancer risk. Conclusions In this large long-term trial of male physicians, neither vitamin E nor C supplementation reduced the risk of prostate or total cancer. These data provide no support for the use of these supplements for the prevention of cancer in middle-aged and older men. Trial Registration http://www.clinicaltrials.gov identifier: NCT00270647

show abstract

Association Between alpha-Tocopherol, gamma-Tocopherol, Selenium, and Subsequent Prostate Cancer

Abstract: The use of combined alpha- and gamma- tocopherol supplements should be considered in upcoming prostate cancer prevention trials, given the observed interaction between alpha-tocopherol, gamma-tocopherol, and selenium.

Cited by 353 publications

References 16 publications

A case–control study of selenium in nails and prostate cancer risk in British men

A case–control study of selenium in nails and prostate cancer risk in British men

Association between the GCG polymorphism of the selenium dependent GPX1 gene and the risk of young onset prostate cancer

Vitamins E and C in the Prevention of Prostate and Total Cancer in Men

Contact Info

Product

Resources

About