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Background: Epidemiologic research suggests that increased cancer risk due to chronic arsenic exposure persists for several decades even after the exposure has terminated. Observational studies suggest that antioxidants exert a protective effect on arsenical skin lesions and cancers among those chronically exposed to arsenic through drinking water. This study reports on the design, methods and baseline analyses from the Bangladesh Vitamin E and Selenium Trial (BEST), a population-based chemoprevention study conducted among adults in Bangladesh with visible arsenic toxicity., Materials and Methods: Bangladesh Vitamin E and Selenium Trial is a 2 × 2 full factorial, double-blind, randomized controlled trial of 7000 adults having manifest arsenical skin lesions evaluating the efficacy of 6-year supplementation with alpha-tocopherol (100 mg daily) and L-selenomethionine (200 μg daily) for the prevention of nonmelanoma skin cancer., Results: In cross-sectional analyses, we observed significant associations of skin lesion severity with male gender (female prevalence odds ratio (POR) = 0.87; 95% CI = 0.79-0.96), older age (aged 36-45 years, POR = 1.27; 95% CI = 1.13-1.42; aged 46-55 years, POR = 1.44; 95% CI = 1.27-1.64 and aged 56-65 years, POR = 1.50; 95% CI = 1.26-1.78 compared with aged 25-35 years), hypertension (POR = 1.29; 95% CI = 1.08-1.55), diabetes (POR = 2.13; 95% CI = 1.32-3.46), asthma (POR = 1.55; 95% CI = 1.03-2.32) and peptic ulcer disease (POR = 1.20; 95% CI = 1.07-1.35)., Conclusions: We report novel associations between arsenical skin lesions with several common chronic diseases. With the rapidly increasing burden of preventable cancers in developing countries, efficient and feasible chemoprevention study designs and approaches, such as employed in BEST, may prove both timely and potentially beneficial in conceiving cancer chemoprevention trials in Bangladesh and beyond., (© 2013 Stichting European Society for Clinical Investigation Journal Foundation. Published by John Wiley & Sons Ltd.)

Cisplatin is one of the most effective chemotherapeutic agents, although its clinical use is limited by severe renal toxicity. This toxicity seems to be related to the accumulation of the drug in kidney tissues, leading to renal failure. For this reason, several compounds have been evaluated to ameliorate the nephrotoxicity induced by cisplatin. In the present investigation, we report the effect of the oral administration of selenomethionine before intraperitoneal cisplatin treatment. The preadministration of this Se species has been shown to have an important effect in reducing renal damage induced by cisplatin by increasing the excreted urea and improving creatinine clearance. Quantification of the level of DNA--cisplatin adducts in kidney and liver tissues was carried out by postcolumn isotope dilution analysis using liquid chromatography-inductively coupled plasma (LC-ICP-MS) as speciation set up. The level of DNA--cisplatin adducts in rats given Se-methionine in the drinking water before cisplatin administration was considerably lower in kidney tissues with respect to the animals drinking only water. Such effects were not observed in liver tissue. Initial speciation studies of Pt and Se conducted in kidney tissues of exposed animals by HPLC-ICP-MS have revealed the presence of cisplatin as part of a complex with Se-methionine, which can be eventually excreted into urine. This Pt--Se complex could explain the observed reduction of the kidney damage in Se-methionine-treated animals.

Context: Secondary analyses of 2 randomized controlled trials and supportive epidemiologic and preclinical data indicated the potential of selenium and vitamin E for preventing prostate cancer., Objective: To determine whether selenium, vitamin E, or both could prevent prostate cancer and other diseases with little or no toxicity in relatively healthy men., Design, Setting, and Participants: A randomized, placebo-controlled trial (Selenium and Vitamin E Cancer Prevention Trial [SELECT]) of 35,533 men from 427 participating sites in the United States, Canada, and Puerto Rico randomly assigned to 4 groups (selenium, vitamin E, selenium + vitamin E, and placebo) in a double-blind fashion between August 22, 2001, and June 24, 2004. Baseline eligibility included age 50 years or older (African American men) or 55 years or older (all other men), a serum prostate-specific antigen level of 4 ng/mL or less, and a digital rectal examination not suspicious for prostate cancer., Interventions: Oral selenium (200 microg/d from L-selenomethionine) and matched vitamin E placebo, vitamin E (400 IU/d of all rac-alpha-tocopheryl acetate) and matched selenium placebo, selenium + vitamin E, or placebo + placebo for a planned follow-up of minimum of 7 years and a maximum of 12 years., Main Outcome Measures: Prostate cancer and prespecified secondary outcomes, including lung, colorectal, and overall primary cancer., Results: As of October 23, 2008, median overall follow-up was 5.46 years (range, 4.17-7.33 years). Hazard ratios (99% confidence intervals [CIs]) for prostate cancer were 1.13 (99% CI, 0.95-1.35; n = 473) for vitamin E, 1.04 (99% CI, 0.87-1.24; n = 432) for selenium, and 1.05 (99% CI, 0.88-1.25; n = 437) for selenium + vitamin E vs 1.00 (n = 416) for placebo. There were no significant differences (all P>.15) in any other prespecified cancer end points. There were statistically nonsignificant increased risks of prostate cancer in the vitamin E group (P = .06) and type 2 diabetes mellitus in the selenium group (relative risk, 1.07; 99% CI, 0.94-1.22; P = .16) but not in the selenium + vitamin E group., Conclusion: Selenium or vitamin E, alone or in combination at the doses and formulations used, did not prevent prostate cancer in this population of relatively healthy men., Trial Registration: clinicaltrials.gov identifier: NCT00006392.

Background: Evidence of the chemopreventive effects of the dietary antioxidants alpha-tocopherol (vitamin E) and l-selenomethionine (selenium) comes from secondary analysis of two phase III clinical trials that found treatment with these antioxidants reduced the incidence of prostate cancer. To determine the effects of selenium and vitamin E in blood and prostate tissue, we undertook a preoperative feasibility study complementary to the currently ongoing Selenium and Vitamin E Cancer Prevention Trial., Methods: Forty-eight patients with clinically localized prostate cancer enrolled on this 2 x 2 factorial design study were randomized to take selenium, vitamin E, both, or placebo for 3 to 6 weeks before prostatectomy. Sera were collected from patients before and after dietary supplementation. Thirty-nine patients were evaluable, and 29 age-matched disease-free men served as controls. Mass profiling of lipophilic serum proteins of lower molecular weight (2-13.5 kDa) was conducted, and mass spectra data were analyzed using custom-designed software., Results: Weighted voting analyses showed a change in sera classification from cancerous to healthy for some patients with prostate cancer after dietary intervention. ANOVA analysis showed significantly different treatment effects on prediction strength changes among the four groups at a 95% confidence level. Eliminating an outlying value and performing post hoc analysis using Fisher's least significant difference method showed that effects in the group treated with the combination were significantly different from those of the other groups., Conclusion: In sera from patients with prostate cancer, selenium and vitamin E combined induced statistically significant proteomic pattern changes associated with prostate cancer-free status.

Background: Oxidative stress, as measured by 8-iso-prostaglandin F(2)(alpha) (8-iso-PGF(2)(alpha)), and depleted antioxidant defenses were shown in stable cystic fibrosis (CF) patients. The plasma fatty acid status of CF patients was linked to oxidative stress after respiratory exacerbations., Objective: We examined changes in plasma 8-iso-PGF(2)(alpha), antioxidant defenses, plasma fatty acid status, and clinical markers resulting from short-term antioxidant supplementation., Design: Forty-six CF patients were randomly assigned to either group A [low dose of supplement (10 mg vitamin E and 500 micro g vitamin A)] or group B [high dose of supplement (200 mg vitamin E, 300 mg vitamin C, 25 mg beta-carotene, 90 micro g Se, and 500 micro g vitamin A)]. Plasma concentrations of 8-iso-PGF(2)(alpha), vitamins E and C, beta-carotene, zinc, selenium, and copper; plasma fatty acid composition; erythrocyte glutathione peroxidase (EC 1.11.1.9) and superoxide dismutase (EC 1.15.1.1) activities; lung function; and dietary intake were measured before and after 8 wk of supplementation., Results: Antioxidant defenses in group B improved, whereas those in group A did not: in groups B and A, the mean (+/- SEM) changes (Delta) in vitamin E were 10.6 +/- 1.5 and -1.9 +/- 0.9 micro mol/L, respectively (P < 0.001), (Delta)beta-carotene were 0.1 +/- 0.04 and -0.01 +/- 0.02 micro mol/L, respectively (P = 0.007), (Delta)selenium were 0.51 +/- 0.10 and -0.09 +/- 0.04 micro mol/L, respectively (P < 0.001), and (Delta)glutathione peroxidase activity were 1.3 +/- 0.3 and -0.3 +/- 0.6 U/g hemoglobin, respectively (P = 0.016). There were no significant differences between the groups in Delta8-iso-PGF(2)(alpha), (Delta)vitamin C, (Delta)fatty acid composition, (Delta)superoxide dismutase activity, (Delta)lung function, or (Delta)white cell count. Within group B, (Delta)beta-carotene correlated with (Delta)percentage of forced vital capacity (r = 0.586, P = 0.005), (Delta)selenium correlated with (Delta)percentage of forced expiratory volume in 1 s (r = 0.440, P = 0.046), and (Delta)plasma fatty acid concentrations correlated with (Delta)percentage of forced expiratory volume in 1 s (r = 0.583, P = 0.006) and Delta8-iso-PGF(2)(alpha) (r = 0.538, P = 0.010)., Conclusions: Whereas increased beta-carotene, selenium, and fatty acid concentrations are linked to improved lung function, increased plasma fatty acid concentrations are linked to oxidative stress. If oxidative stress is deemed to be important to the clinical outcome of CF patients, means of reducing oxidative stress while maintaining a high-fat, high-energy diet must be investigated.

Drinking water supplemented with selenium (8 ppm, daily) has been found to be highly effective in reducing tumor incidence and preneoplastic foci in 2-acetylaminofluorene (2-AAF) induced hepatocarcinogenesis in Sprague-Dawley male rats. Glutathione and several enzymes in liver tissue associated with antioxidant defense mechanisms, viz., catalase, glutathione-S-transferase, glutathione peroxidase, glutathione reductase and superoxide dismutase were investigated from hyperplastic nodules and non-nodular surrounding parenchyma. Treatment with selenomethionine either on initiation, or on selection/promotion, or during the entire experiment showed that selenom-ethionine was most effective when it was used as a supplement during the entire experiment, in terms of the antioxidant defense system and in reducing tumor incidence. Our results also confirm that selenium is particularly effective in limiting the action of 2-AAF during the initiation phase of hepatocarcinogenesis.

Selenium concentration in blood, glutathionperoxidase (GSH-Px) activity in erythrocytes and lipid peroxides in plasma were studied in patients with ischemic heart disease, hypertrophic (HCMP) and dilated cardiomyopathy (DCMP). Patients with IHD, HCMP and DCMP revealed depressed activity of GSH-Px with activation of lipid peroxides associated with lowered selenium content in blood. The selenium content in blood was lower in patients with severe forms of IHD Daily intake of 300 micrograms selenium with "Selena" during a month increases selenium concentration by 71% in patients with IHD and DCMP. This increase change inversely with primary selenium concentration in plasma. Plasma Malone dialdehyde concentration decreased by 17%. The results obtained suggest participation of selenium in cardiomyopathy and IHD pathogenesis, thus forming a basis for selecting the patients with selenium deficiency for its further correction with "Selena."

Sixty-one patients admitted with acute myocardial infarction, and a symptom's duration of less than 6 hr were randomized into two groups. Immediately after hospitalisation, members of the verum group (n = 32) received 500 mcg of selenium (as sodium selenite). Thereafter they received a daily dosage of 100 mg coenzyme Q10 (Bio-Quinone) and 100 mcg selenium (Bio-Selenium in the form of 1-seleno-methionine) for a period of one year. The control group (n = 29) were given matching placebo preparations. The groups were comparable as with respect to age, sex and medical treatment. Biochemical parameters showed a reduced concentration of CPK- and ASAT-level in the verum group during the acute phase (although not statistically significant). None of the patients in the verum group (i.e. on antioxidative treatment) showed prolongation of the frequency corrected QT-interval. In the control group, 40% revealed a prolongation of the QT-interval by more than 440 msec (p < 0.001). There were no significant differences, with respect to early complications. During the one-year follow-up period after myocardial infarction, six patients (20%) from the control group died from re-infarction whereas one patient from the verum group suffered a non-cardiac death.