In an ongoing randomized pilot study in phase I clinical trial investigating the impact of quercetin on EGCG uptake in prostate cancer, the downregulating effects of quercetin on enzyme function and protein and gene expression of COMT (catechol-O-methyltransferase) and DNMT1 are being assessed (NCT01912820). This evidence concerns the gene DNMT1 and Familial prostate cancer.