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  Supplemental and dietary vitamin E, beta-carotene, and vitamin C intakes and prostate cancer risk.

  Kirsh, Victoria A.; Hayes, Richard B.; Mayne, Susan T.; Chatterjee, Nilanjan; Subar, Amy F.; Dixon, L. Beth; Albanes, Demetrius; Andriole, Gerald L.; Urban, Donald A.; Peters, Ulrike (2006-02-15)

  BACKGROUND: Vitamin E, beta-carotene, and vitamin C are micronutrient antioxidants that protect cells from oxidative damage involved in prostate carcinogenesis. In separate trials, supplemental vitamin E was associated with a decreased risk of prostate cancer among smokers and supplemental beta-carotene was associated with a decreased risk of prostate cancer among men with low baseline plasma beta-carotene levels. METHODS: We evaluated the association between intake of these micronutrient antioxidants from foods and supplements and the risk of prostate cancer among men in the screening arm of the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. At baseline, trial participants completed a 137-item food frequency questionnaire that included detailed questions on 12 individual supplements. Cox proportional hazards models were used to estimate relative risks (RRs) and 95% confidence intervals (CIs). All statistical tests were two-sided. RESULTS: We identified 1338 cases of prostate cancer among 29 361 men during up to 8 years of follow-up. Overall, there was no association between prostate cancer risk and dietary or supplemental intake of vitamin E, beta-carotene, or vitamin C. However, among current and recent (i.e., within the previous 10 years) smokers, decreasing risks of advanced prostate cancer (i.e., Gleason score > or = 7 or stage III or IV) were associated with increasing dose (RR for > 400 IU/day versus none = 0.29, 95% CI = 0.12 to 0.68; Ptrend = .01) and duration (RR for > or = 10 years of use versus none = 0.30, 95% CI = 0.09 to 0.96; Ptrend = .01) of supplemental vitamin E use. Supplemental beta-carotene intake at a dose level of at least 2000 microg/day was associated with decreased prostate cancer risk in men with low (below the median of 4129 microg/day) dietary beta-carotene intake (RR = 0.52, 95% CI = 0.33 to 0.81). Among smokers, the age-adjusted rate of advanced prostate cancer was 492 per 100,000 person-years in those who did not take supplemental vitamin E, 153 per 100,000 person-years in those who took more than 400 IU/day of supplemental vitamin E, and 157 per 100,000 person-years in those who took supplemental vitamin E for 10 or more years. Among men with low dietary beta-carotene intake, the age-adjusted rate of prostate cancer was 1122 per 100,000 person-years in those who did not take supplemental beta-carotene, and 623 per 100,000 person-years in those who took at least 2000 microg/day of supplemental beta-carotene. CONCLUSIONS: Our results do not provide strong support for population-wide implementation of high-dose antioxidant supplementation for the prevention of prostate cancer. However, vitamin E supplementation in male smokers and beta-carotene supplementation in men with low dietary beta-carotene intakes were associated with reduced risk of this disease.
• Urinary excretion rates of 8-oxoGua and 8-oxodG and antioxidant vitamins level as a measure of oxidative status in healthy, full-term newborns.

  Dziaman, Tomasz; Gackowski, Daniel; Rozalski, Rafal; Siomek, Agnieszka; Szulczynski, Jaroslaw; Zabielski, Romuald; Olinski, Ryszard (2007-09)

  The aim of the present study was to evaluate the oxidative status in healthy full-term children and piglets. Urinary excretion of 8-oxoGua (8-oxoguanine) and 8-oxodG (8-oxo-2'-deoxyguanosine) were determined using HPLC/GS/MS methodology and concentrations of vitamins A, C and E with HPLC technique. The levels of 8-oxoGua in urine samples were about 7-8 times higher in newborn children and piglets when compared with the level of adult subjects, while in the case of 8-oxodG the difference was about 2.5 times. The levels of vitamin C and E in umbilical cord blood of newborn children significantly depend on the concentration of these compounds in their mother's blood. However, the values of vitamin C in human's cord blood were about 2-times higher than in respective mother blood, while the level of vitamin E showed an opposite trend. The results suggest that: (i) healthy, full-term newborns are under potential oxidative stress; (ii) urinary excretion of 8-oxoGua and 8-oxodG may be a good marker of oxidative stress in newborns; and (iii) antioxidant vitamins, especially vitamin C, play an important role in protecting newborns against oxidative stress.
• Dietary intake of vitamin K and risk of prostate cancer in the Heidelberg cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC-Heidelberg).

  Nimptsch, Katharina; Rohrmann, Sabine; Linseisen, Jakob (2008-04)

  BACKGROUND: Anticarcinogenic activities of vitamin K have been observed in various cancer cell lines, including prostate cancer cells. Epidemiologic studies linking dietary intake of vitamin K with the development of prostate cancer have not yet been conducted. OBJECTIVE: We evaluated the association between dietary intake of phylloquinone (vitamin K1) and menaquinones (vitamin K2) and total and advanced prostate cancer in the Heidelberg cohort of the European Prospective Investigation into Cancer and Nutrition. DESIGN: At baseline, habitual dietary intake was assessed by means of a food-frequency questionnaire. Dietary intake of phylloquinone and menaquinones (MK-4-14) was estimated by using previously published HPLC-based food-content data. Multivariate-adjusted relative risks of total and advanced prostate cancer in relation to intakes of phylloquinone and menaquinones were calculated in 11 319 men by means of Cox proportional hazards regression. RESULTS: During a mean follow-up time of 8.6 y, 268 incident cases of prostate cancer, including 113 advanced cases, were identified. We observed a nonsignificant inverse association between total prostate cancer and total menaquinone intake [multivariate relative risk (highest compared with lowest quartile): 0.65; 95% CI: 0.39, 1.06]. The association was stronger for advanced prostate cancer (0.37; 0.16, 0.88; P for trend = 0.03). Menaquinones from dairy products had a stronger inverse association with advanced prostate cancer than did menaquinones from meat. Phylloquinone intake was unrelated to prostate cancer incidence (1.02; 0.70, 1.48). CONCLUSIONS: Our results suggest an inverse association between the intake of menaquinones, but not that of phylloquinone, and prostate cancer. Further studies of dietary vitamin K and prostate cancer are warranted.