Poster Topical Area: Dietary Bioactive Components
Location: Hall D
Poster Board Number: 356
Epidemiological evidence suggests that tomato products or lycopene are associated with reduced prostate cancer (PCa) incidence, yet little information exists regarding the ability of tomatoes or its bioactive components to impact PCa therapy. Castration-resistant prostate cancer (CRPC) is the result of progression following androgen deprivation therapy (ADT). CRPC is an advanced phase of PCa in humans with a poor prognosis. In our present study, we hypothesized that dietary tomato or an equivalent concentration of lycopene following orchiectomy would reduce tumor burden and progression in transgenic adenocarcinoma of the mouse prostate (TRAMP) mice compared controls diet.
To test this hypothesis, male TRAMP mice (n=90) were provided a powdered AIN-93G diet (BASE) until 12 weeks of age. To model the effects of ADT (reducing serum testosterone), mice were castrated at 12 weeks. After castration, animals consumed either BASE with placebo beadlets (Placebo, n=30), an AIN-93G diet modified to contain 10% lyophilized tomato paste (TP; n=30), or BASE fed lycopene at a concentration matched to TP (LYCO, n=30). Prostates of TRAMP mice were monitored by ultrasound for in vivo tumor detection and 3-D volumetric growth measurement. Following euthanasia, tissues are collected, and carotenoids are measured by high performance liquid chromatography (HPLC) in the tumor, serum, liver, and epidydimal adipose tissue. Prostate tissue and all suspected metastatic sites are harvested, processed, stained and evaluated by histopathologic criteria.
This study will be the first to compare the effects of tomato powder and lycopene on PCa progression in the TRAMP model following castration. In a preliminary study we have observed that tomato powder following orchiectomy (ADT) was sufficient to reduce CRPC growth rate and volume in this model. Accordingly, we hypothesize that TP and LYCO will both reduce CRPC tumor recurrence, CRPC tumor growth and extend tumor-free survival compared to Placebo, and that TP will have a greater reduction than LYCO due to the additional carotenoids that may accumulate in the tumor to protect against progression.
This work was supported by USDA NIFA ILLU-971-334 and NIH R37EB002641
University of Illinois at Urbana-Champaign