Study shows how broccoli prevents cancer

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I have the full pdf version if anyone wants it:

Broccoli Consumption Interacts with GSTM1 to Perturb Oncogenic

Signalling Pathways in the Prostate

Traka1, Amy V. Gasper, Antonietta Melchini1,, R. Bacon1,

W. Needs1, Frost3, Chantry, andra M. E.

, Catharine A. Ortori, A. Barrett5, Y. Ball6,

D. Mills, F. Mithen1*

Epidemiological studies suggest that people who consume more than one

portion of cruciferous vegetables per week are at lower risk of both

the incidence of prostate cancer and of developing aggressive prostate

cancer but there is little understanding of the underlying mechanisms.

In this study, we quantify and interpret changes in global gene

expression patterns in the human prostate gland before, during and

after a 12 month broccoli-rich diet.

Methods and Findings

Volunteers were randomly assigned to either a broccoli-rich or a

pea-rich diet. After six months there were no differences in gene

expression between glutathione S-transferase mu 1 (GSTM1) positive and

null individuals on the pea-rich diet but significant differences

between GSTM1 genotypes on the broccoli-rich diet, associated with

transforming growth factor beta 1 (TGF & #946;1) and epidermal growth factor

(EGF) signalling pathways. Comparison of biopsies obtained pre and

post intervention revealed more changes in gene expression occurred in

individuals on a broccoli-rich diet than in those on a pea-rich diet.

While there were changes in androgen signalling, regardless of diet,

men on the broccoli diet had additional changes to mRNA processing,

and TGF & #946;1, EGF and insulin signalling. We also provide evidence that

sulforaphane (the isothiocyanate derived from 4-methylsuphinylbutyl

glucosinolate that accumulates in broccoli) chemically interacts with

TGF & #946;1, EGF and insulin peptides to form thioureas, and enhances

TGF & #946;1/Smad-mediated transcription.

Conclusions

These findings suggest that consuming broccoli interacts with GSTM1

genotype to result in complex changes to signalling pathways

associated with inflammation and carcinogenesis in the prostate. We

propose that these changes may be mediated through the chemical

interaction of isothiocyanates with signalling peptides in the plasma.

This study provides, for the first time, experimental evidence

obtained in humans to support observational studies that diets rich in

cruciferous vegetables may reduce the risk of prostate cancer and

other chronic disease.

Diane