glycitein and Prostatic-Neoplasms

This updated meta-analysis was performed to clarify the relationship between phytoestrogens and prostate cancer risk. Twenty one case-control and two cohort studies were finally selected for this meta-analysis, totaling 11,346 cases and 140,177 controls. Analytical results showed that daidzein (OR = 0.85; 95% CI: 0.75-0.96), genistein (OR = 0.87; 95% CI: 0.78-0.98), and glycitein (OR = 0.89; 95% CI: 0.81-0.98) were associated with a reduction of prostate cancer risk, but total isoflavones (OR = 0.93; 95% CI: 0.84-1.04), equol (OR = 0.86; 95% CI: 0.66-1.14), total lignans (OROgna.05; 95% CI: 0.54-2.04), secoisolariciresinol (OR = 1.02; 95% CI: 0.83-1.24), matairesinol (OR = 0.91; 95% CI: 0.75-1.11), enterolactone (OR = 0.94; 95% CI: 0.73-1.20), and coumestrol (OR = 0.89; 95% CI: 0.76-1.06) were not. Sensitivity and publication bias analyses demonstrated that the pooled estimates were stable and reliable. The results support the notion that some phytoestrogens may have a role in decreasing the risk of prostate cancer. Additional large and well-designed cohort studies are needed to confirm these relationships.

Topics: Case-Control Studies; Cohort Studies; Diet, Healthy; Evidence-Based Medicine; Genistein; Humans; Isoflavones; Male; Men's Health; Phytoestrogens; Prostatic Neoplasms; Risk

To determine the effects of diets rich in soy and linseed compared with a control diet on biochemical markers of prostate cancer in men diagnosed with prostate cancer.. Twenty-nine men diagnosed with prostate cancer and scheduled to undergo a radical prostatectomy were randomized to one of three groups: soy (high phytoestrogen), soy and linseed (high phytoestrogen), or wheat (low phytoestrogen). A bread was specially manufactured to incorporate 50 g of heat-treated (HT) soy grits or 50 g of HT soy grits and 20 g of linseed as part of the study participant's daily diet. Baseline and preoperative levels of prostate-specific antigen (PSA), free PSA, testosterone, sex hormone-binding globulin, free androgen index, and dihydrotestosterone were measured.. Statistically significant differences were detected between the HT soy grits group and the control wheat group for the percentage of change in total PSA (-12.7% versus 40%, P = 0.02) and the percentage of change in free/total PSA ratio (27.4% versus -15.6%, P = 0.01); and between the HT soy grits group and the HT soy grits and linseed group for the percentage of change in free androgen index (16.4% versus -15.5%, P = 0.04) and the percentage of change in free/total PSA ratio (27.4% versus -10%, P = 0.007).. The data from this study indicate that a daily diet containing four slices of a bread rich in HT soy grits favorably influences the PSA level and the free/total PSA ratio in patients with prostate cancer. This work provides some evidence to support epidemiologic studies claiming that male populations who consume high phytoestrogen diets have a reduced risk of prostate cancer development and progression.

Topics: Adenocarcinoma; Aged; Androgens; Biomarkers, Tumor; Bread; Dihydrotestosterone; Double-Blind Method; Flax; Genistein; Gonadal Steroid Hormones; Humans; Isoflavones; Male; Middle Aged; Neoplasm Proteins; Phytoestrogens; Phytotherapy; Prostate-Specific Antigen; Prostatic Neoplasms; Sex Hormone-Binding Globulin; Soy Foods; Testosterone

Genistein may be useful in the prevention or treatment of prostate cancer; however, it causes genetic damage in cultured human cells.. The objective was to assess the potential genotoxicity of a purified soy unconjugated isoflavone mixture in men with prostate cancer.. Twenty patients with prostate cancer were treated with 300 mg genistein/d for 28 d and then with 600 mg/d for another 56 d. In peripheral lymphocytes, DNA strand breaks were assessed as nuclear tail moment, chromosomal damage was assessed as micronucleus frequency (MF), and translocations of the MLL gene (11q23) were assessed by using fluorescence in situ hybridization. Values are also reported for 6 healthy men. The studies were performed under Investigational New Drug application no. 54 137 at a tertiary referral academic medical center.. No changes in group average or individual nuclear tail moment and MF were observed. We observed a single elevated MF value in one subject that exceeded a clinical threshold set before we initiated the study. A significant decrease in average COMET tail moment was observed on day 28 relative to day 0. We detected no genistein-induced rearrangements of the MLL gene in the 3 subjects we studied with this technique. MF increased significantly in lymphocytes exposed in vitro to unconjugated genistein at concentrations > or = 100 micromol/L. Total genistein never exceeded a peak concentration of 27.1 micro mol/L, and unconjugated genistein never exceeded a peak concentration of 0.32 micromol/L.. Although isoflavones are capable of inducing genetic damage in vitro, a similar effect was not observed in subjects treated with a purified soy unconjugated isoflavone mixture.

Topics: Adult; Cells, Cultured; Comet Assay; DNA Damage; DNA-Binding Proteins; Gene Deletion; Genistein; Glycine max; Histone-Lysine N-Methyltransferase; Humans; In Situ Hybridization, Fluorescence; Isoflavones; Lymphocytes; Male; Micronuclei, Chromosome-Defective; Myeloid-Lymphoid Leukemia Protein; Prostatic Neoplasms; Proto-Oncogenes; Transcription Factors; Translocation, Genetic

Isoflavones may play a role in the prevention of hormone-related cancers. Equol is an isoflavone metabolized from daidzein in the presence of certain intestinal bacteria. Slackia sp. strain NATTS, a newly identified equol-producing bacterium, was recently isolated from human feces in Japan. We investigated the association of serum levels and dietary intake of isoflavones and Slackia sp. strain NATTS with the risk of prostate cancer in a case-control study among Japanese men.. Fifty-six patients with newly diagnosed prostate cancer and 56 hospital controls were enrolled in this study. Isoflavones were assessed by measurement of serum levels and administration of a food frequency questionnaire. Slackia sp. strain NATTS in feces was also measured. The odds ratios (ORs) and 95 % confidence intervals (CIs) for prostate cancer were then determined using a logistic regression model.. The adjusted ORs for prostate cancer in comparison with the highest to lowest categories were 0.06 (95 % CI 0.02-0.24) for serum genistein, 0.18 (95 % CI 0.06-0.52) for daidzein, 0.16 (95 % CI 0.06-0.46) for glycitein, 0.52 (95 % CI 0.22-1.22) for equol, 0.86 (95 % CI 0.30-2.48) for dietary genistein, and 0.80 (95 % CI 0.28-2.28) for dietary daidzein. The adjusted OR for prostate cancer in comparison with values above versus below the median was 0.95 (95 % CI 0.42-2.16) for Slackia sp. strain NATTS.. Our study findings suggest that high serum levels of genistein, daidzein, and glycitein are significantly associated with a decreased risk of prostate cancer among Japanese men.

Topics: Actinobacteria; Aged; Case-Control Studies; Diet; Equol; Feces; Genistein; Humans; Isoflavones; Japan; Male; Middle Aged; Odds Ratio; Prostatic Neoplasms; Surveys and Questionnaires

The objective of the present study is to explore the association between lower urinary tract symptoms (LUTS) and dietary isoflavone in elderly men. In a large prospective cohort of 2000 Chinese men, the association between dietary isoflavone and LUTS were studied using standardized structured questionnaires. Dietary intake was assessed by a modified version of the Block FFQ. LUTS were assessed by the Chinese version of the International Prostatic Symptoms Score. Demographic, lifestyle and other medical information were also collected and were adjusted for in the analysis. After excluding 299 men with history of bladder surgery, bladder or prostate cancer or who were current users of medication for urinary problems, the association between LUTS and dietary isoflavone was explored. A total of 96.2 % of subjects reported some consumption of genistein, glycitein or daidzein. In ordinal multinominal logistic regression, subjects with dietary total isoflavone of more than 5.1 mg were significantly less likely to suffer from more severe LUTS (dietary intake from 5.1 to 9.5 mg: OR 0.59; 95 % CI 0.44, 0.80; from 9.6 to 14.3 mg: OR 0.81; 95 % CI 0.61, 1.09; from 14.4 to 21.7 mg: OR 0.68; 95 % CI 0.51, 0.92; 21.8 mg and above: OR 0.73; 95 % CI 0.54, 0.98) after adjustment for covariates. In this cross-sectional study, we showed a strong inverse association between dietary intake of isoflavone and the risk of LUTS.

Topics: Aged; Alcohol Drinking; China; Cross-Sectional Studies; Diet; Feeding Behavior; Genistein; Glycine max; Humans; Isoflavones; Logistic Models; Male; Prospective Studies; Prostatic Hyperplasia; Prostatic Neoplasms; Risk Factors; Smoking; Surveys and Questionnaires; Urination Disorders