A Human Intervention Trial Studying Gene Expression in High-Grade Prostatic Intraepithelial Neoplasia Following Consumption of Broccoli or Peas

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.