This is a parallel human intervention trial to determine to what extent a dietary intervention of broccoli or peas can change the expression (switching on or off) of genes in prostate tissue in men diagnosed with high-grade Prostate Intraepithelial Neoplasia (PIN).

Cancer is one of the main causes of death among humans in the world. Prostate cancer affects 20,000 men in the UK alone each year. Diet is known to be a major factor that influences risk of cancer. Therefore, changes to the diet may alter cancer risk. Cruciferous vegetables, particularly broccoli, provide the diet with a substantial source of plant chemicals called glucosinolates. Previous research has indicated that glucosinolates break down to form isothiocyanates (ITCs) that can be absorbed in the body. Further research has indicated that ITCs may protect the body against the development of prostate cancer. However, the mechanisms behind this effect are not fully understood.

ITCs are thought to be powerful anti cancer agents as they can modulate the expression (switching on or off) of specific genes involved in the removal of toxic substances such as carcinogens from the body. In this study we wish to evaluate the effect of consumption of a conventionally bred cultivar of broccoli containing high levels of ITCs on gene expression in prostate tissue to gain a better understanding of its mechanism of action. Several studies suggest a further protection against cancer amongst individuals who have a deletion of certain genes.

This pilot study comprises a 12-month intervention of either 400g ITC-enriched broccoli per week of 400g garden peas in men at high risk of developing prostate cancer. Changes in gene expression of prostate biopsy tissue will be compared before and after 6 and 12 months of intervention in both dietary groups.

• Dietary Supplement: Broccoli
  400g ITC-enriched broccoli per week for 12 months
• Dietary Supplement: Peas
  400g frozen garden peas per week for 12 months

• Experimental: 1
  Dietary intervention of ITC-enriched broccoli
  Intervention: Dietary Supplement: Broccoli
• Experimental: 2
  Dietary intervention of frozen peas
  Intervention: Dietary Supplement: Peas

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Inclusion Criteria:

• Men with a previous diagnosis of high-grade Prostatic Intraepithelial Neoplasia
• BMI >18.5 or <35
• Aged between 30-70 years

Exclusion Criteria:

• Undergoing chemopreventive therapy
• Receiving testosterone replacement medicines
• Active infection requiring treatment
• BMI <18.5 or >35
• Diagnosed with diabetes
• Unable to give informed consent