Tomato Sauce Supplementation and Prostate Cancer: Lycopene Accumulation and Modulation of Biomarkers of Carcinogenesis
As part of a randomized placebo-controlled study to evaluate the effect of lycopene supplementation on DNA damage in men with prostate cancer, a nonrandomized 5th arm using tomato sauce was included and reported here. Thirty-two patients with localized prostate adenocarcinoma consumed tomato sauce-based pasta dishes for 3 weeks (30 mg of lycopene/day) before their scheduled radical prostatectomy. Prostate tissue was obtained as biopsies at baseline and as resected tissue at the time of the prostatectomy. Serum and prostate lycopene, serum prostate specific antigen (PSA) concentrations, and leukocyte DNA 8-OH-deoxyguanosine/deoxyguanosine (80HdG) were measured at baseline and at the end of the intervention. Cancer cells in paraffin sections of prostate biopsies and postintervention resected tissue were compared for 80HdG staining and for apoptosis. Adherence to the daily consumption of tomato-based entrees was 81.6% of the intended dose, and serum and prostate lycopene concentrations increased 1.97- and 2.92-fold (P< 0.001), respectively. Mean serum PSA concentrations decreased by 17.5% (P< 0.002) and leukocyte 80HdG decreased by 21.3% (P< 0.005) after tomato sauce consumption. Resected tissues from tomato sauce-supplemented patients had 28.3% lower prostate 80HdG compared with the nonstudy control group (P < 0.03). Cancer cell 80HdG staining of Gleason Score-matched resected prostate sections was reduced by 40.5% in mean nuclear density (P < 0.005) and by 36.4% in mean area (P < 0.018) compared with the presupplementation biopsy. Apoptotic index was higher in hyperplastic and neoplastic cells in the resected tissue after supplementation. These data taken as a whole indicate significant uptake of lycopene into prostate tissue and a reduction in DNA damage in both leukocyte and prostate tissue. Whether reduction in DNA. damage to prostate cancer cells is beneficial awaits further research, although reduction in serum PSA concentrations is promising.