Lignans and isoflavonoids in plasma and prostatic fluid in men: Samples from Portugal, Hong Kong, and the United Kingdom

Morton, Michael S. Scott; Chan, Peter S.; Chen, Cheng; Blacklock, N. J.; Matos-Ferreira, A.; Abranches-Monteiro, Luis; Correia, Rafael Ribeiro; Lloyd, S. N.; Griffiths, K.

doi:10.1002/(sici)1097-0045(19970701)32:2<122::aid-pros7>3.0.co;2-o

Cited by 210 publications

(140 citation statements)

References 36 publications

Supporting

Mentioning

130

Contrasting

Unclassified

Order By: Relevance

“…This result has been confirmed by others, however, the concentrations needed to achieve this inhibition in cell culture (>50 M) are two to three orders of magnitude greater than those observed in Asian men eating soy as a significant part of the diet [21]. This suggests that if isoflavones have an effect in vivo, then they do so via secondary mechanisms.…”

Section: Introductionsupporting

confidence: 68%

Soy isoflavonoids and cancer — metabolism at the target site

Boersma

Barnes

Kirk

et al. 2001

Mutation Research/Fundamental and Molecular Mechanisms of Mutag

View full text Add to dashboard Cite

Section: Introductionsupporting

confidence: 68%

Soy isoflavonoids and cancer — metabolism at the target site

Boersma

Barnes

Kirk

et al. 2001

Mutation Research/Fundamental and Molecular Mechanisms of Mutag

View full text Add to dashboard Cite

“…On the other hand, a large sample of prostatic fluid concentrations indicates that isoflavone and lignan concentrations are higher on average than mean plasma levels (79,80) (Table 12). Plasma and prostatic fluid concentrations in individual men were well correlated for DAI (r s = 0.7) but not for enterolactone (r s = 0.2-0.4) (80), suggesting that isoflavones are concentrated in the prostate.…”

Section: Tissue Concentrationsmentioning

confidence: 99%

“…Low rates of breast cancer in populations with high phytoestrogen exposure suggest phytoestrogens may inhibit epithelial cell proliferation (9,65,(103)(104)(105)(106). On the other hand, the biphasic effects on proliferation observed in in vitro studies suggest that both proliferative and antiproliferative effects might be observed, depending on the dose.…”

Section: Proliferation Of Breast Epitheliummentioning

confidence: 99%

Cross-species and interassay comparisons of phytoestrogen action.

Whitten

Patisaul

2001

Environ Health Perspect

174

105

View full text Add to dashboard Cite

This paper compiles animal and human data on the biologic effects and exposure levels of phytoestrogens in order to identify areas of research in which direct species comparisons can be made. In vitro and in vivo assays of phytoestrogen action and potency are reviewed and compared to actions, dose-response relationships, and estimates of exposure in human subjects. Binding studies show that the isoflavonoid phytoestrogens are high-affinity ligands for estrogen receptors (ERs), especially ER beta, but have lower potency in whole-cell assays, perhaps because of interactions with binding proteins. Many other enzymatic actions require concentrations higher than those normally seen in plasma. In vivo data show that phytoestrogens have a wide range of biologic effects at doses and plasma concentrations seen with normal human diets. Significant in vivoresponses have been observed in animal and human tests for bone, breast, ovary, pituitary, vasculature, prostate, and serum lipids. The doses reported to be biologically active in humans (0.4--10 mg/kg body weight/day) are lower than the doses generally reported to be active in rodents (10--100 mg/kg body weight/day), although some studies have reported rodent responses at lower doses. However, available estimates of bioavailability and peak plasma levels in rodents and humans are more similar. Steroidogenesis and the hypothalamic-pituitary-gonadal axis appear to be important loci of phytoestrogen actions, but these inferences must be tentative because good dose-response data are not available for many end points. The similarity of reported proliferative and antiproliferative doses illustrates the need for fuller examination of dose-response relationships and multiple end points in assessing phytoestrogen actions.

show abstract

“…1 In East Asian countries (China and Japan), diets are up to 100 times more abundant in flavonoids than in the West, due in part to the consumption of soy and green tea. 2,3 Correspondingly, the incidence of PCa in China and Japan is 60-to 80-fold lower than in North America. 4 Studies on Japanese migrants to the United States have shown that migrants born in Japan and living in the United States have a higher incidence of PCa compared to men living in Japan.…”

Section: Introductionmentioning

confidence: 99%

Novel antiproliferative flavonoids induce cell cycle arrest in human prostate cancer cell lines

Haddad

Venkateswaran

Viswanathan

et al. 2005

Prostate Cancer Prostatic Dis

150

View full text Add to dashboard Cite

Epidemiologic studies have demonstrated an inverse association between flavonoid intake and prostate cancer (PCa) risk. The East Asian diet is very high in flavonoids and, correspondingly, men in China and Japan have the lowest incidence of PCa worldwide. There are thousands of different naturally occurring and synthetic flavonoids. However, only a few have been studied in PCa. Our aim was to identify novel flavonoids with antiproliferative effect in PCa cell lines, as well as determine their effects on cell cycle. We have screened a representative subgroup of 26 flavonoids for antiproliferative effect on the human PCa (LNCaP and PC3), breast cancer (MCF-7), and normal prostate stromal cell lines (PrSC). Using a fluorescence-based cell proliferation assay (Cyquant), we have identified five flavonoids, including the novel compounds 2,2 0 -dihydroxychalcone and fisetin, with antiproliferative and cell cycle arresting properties in human PCa in vitro. Most of the flavonoids tested exerted antiproliferative effect at lower doses in the PCa cell lines compared to the non-PCa cells. Flow cytometry was used as a means to determine the effects on cell cycle. PC3 cells were arrested in G2/M phase by flavonoids. LNCaP cells demonstrated different cell cycle profiles. Further studies are warranted to determine the molecular mechanism of action of 2,2 0 -DHC and fisetin in PCa, and to establish their effectiveness in vivo.

show abstract

Lignans and isoflavonoids in plasma and prostatic fluid in men: Samples from Portugal, Hong Kong, and the United Kingdom

Cited by 210 publications

References 36 publications

Soy isoflavonoids and cancer — metabolism at the target site

Soy isoflavonoids and cancer — metabolism at the target site

Cross-species and interassay comparisons of phytoestrogen action.

Novel antiproliferative flavonoids induce cell cycle arrest in human prostate cancer cell lines

Contact Info

Product

Resources

About