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- Hedelin, Maria, et al.
(författare)
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Dietary intake of phytoestrogens, estrogen receptor-beta polymorphisms and the risk of prostate cancer
- 2006
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Ingår i: The Prostate. - Karolinska Inst, Dept Med Epidemiol & Biostat, SE-17177 Stockholm, Sweden. Orebro Univ Hosp, Dept Urol, Orebro, Sweden. Ctr Assessment Med Technol, Orebro, Sweden. Umea Univ, Dept Radiat Sci Oncol, Umea, Sweden. Harvard Univ, Sch Publ Hlth, Dept Epidemiol, Boston, MA 02115 USA. : Wiley-Liss. - 0270-4137 .- 1097-0045. ; 66:14, s. 1512-1520
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The causes of prostate cancer are poorly understood, but genetic factors may be more important than for many other malignancies, and dietary phytoestrogens may be protective. Because phytoestrogens bind tightly to the estrogen receptor-beta, we conducted an epidemiologic investigation of synergistic effects between phytoestrogen intake and estrogen receptor-beta gene polymorphisms. METHODS: We performed a population-based case-control study in Sweden. All participants reported their phytoestrogen intake and donated a blood sample. We identified four haplotype-tagging single nucleotide polymorphisms (htSNPs) and genotyped these htSNPs in 1314 prostate cancer patients and 782 controls. Odds ratios were estimated by multivariate logistic regression. Interactions between phytoestrogen intake and estrogen receptor-beta SNPs on prostate cancer risk were evaluated considering both multiplicative and additive effect scales. RESULTS: We found a significant multiplicative interaction (P = 0.04) between dietary intake of phytoestrogens and a promoter SNP in the estrogen receptor-beta gene (rs 2987983-13950), but not with any of the three other htSNPs (P = 0.11, 0.69, 0.85). Among carriers of the variant promoter alleles, we found strong inverse associations with increasing intake of total phytoestrogens (odds ratio for highest vs. lowest quartile = 0.43; P for trend <0.001), isoflavonoids (odds ratio = 0.63; P for trend = 0.05), and coumestrol (odds ratio = 0.57; P for trend = 0.003). We found no association between phytoestrogens and prostate cancer among carriers homozygous for the wild-type allele (TT). CONCLUSIONS: Our study provides strong evidence that high intake of phytoestrogens substantially reduce prostate cancer risk among men with specific polymorphic variation in the promoter region of the estrogen receptor-beta gene.
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| 2. |
- Hedelin, Maria, et al.
(författare)
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Dietary phytoestrogen, serum enterolactone and risk of prostate cancer : the cancer prostate Sweden study (Sweden)
- 2006
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Ingår i: Cancer Causes and Control. - Karolinska Inst, Dept Med Epidemiol & Biostat, SE-17177 Stockholm, Sweden. Orebro Univ Hosp, Dept Urol, Orebro, Sweden. Ctr Assessment Med Technol, Orebro, Sweden. Univ Helsinki, Dept Clin Chem, SF-00100 Helsinki, Finland. Univ Helsinki, Inst Prevent Med Nutr & Canc, Folkhalsan Res Ctr, Helsinki, Finland. Umea Univ, Dept Radiat Sci Oncol, Umea, Sweden. : Springer. - 0957-5243 .- 1573-7225. ; 17:2, s. 169-180
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Based on evidence that phytoestrogens may protect against prostate cancer, we evaluated the associations between serum enterolactone concentration or dietary phytoestrogen intake and risk of prostate cancer. METHODS: In our Swedish population-based case-control study, questionnaire-data were available for 1,499 prostate cancer cases and 1,130 controls, with serum enterolactone levels in a sub-group of 209 cases and 214 controls. Unconditional logistic regression was performed to estimate multivariate odds ratios (ORs) and 95% confidence intervals (CIs) for associations with risk of prostate cancer. RESULTS: High intake of food items rich in phytoestrogens was associated with a decreased risk of prostate cancer. The OR comparing the highest to the lowest quartile of intake was 0.74 (95% CI: 0.57-0.95; p-value for trend: 0.01). In contrast, we found no association between dietary intake of total or individual lignans or isoflavonoids and risk of prostate cancer. Intermediate serum levels of enterolactone were associated with a decreased risk of prostate cancer. The ORs comparing increasing quartiles of serum enterolactone concentration to the lowest quartile were, respectively, 0.28 (95% CI: 0.15-0.55), 0.63 (95% CI: 0.35-1.14) and 0.74 (95% CI: 0.41-1.32). CONCLUSIONS: Our results support the hypothesis that certain foods high in phytoestrogens are associated with a lower risk of prostate cancer.
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