A Phase II Randomized Trial of Lycopene-Rich Tomato Extract Among Men with High-Grade Prostatic Intraepithelial Neoplasia.

A diverse body of evidence suggests that lycopene might inhibit prostate cancer development. We conducted a 6-mo repeat biopsy randomized trial among men with high-grade prostatic intraepithelial neoplasia (HGPIN). Here we report results for serum lycopene, prostate specific antigen (PSA) and insulin-like growth factor (IGF) proteins, histopathological review, and tissue markers for proliferation [minichromosome maintenance protein 2 (MCM-2)] and cell cycle inhibition (p27). Participants consumed placebo or tomato extract capsules containing 30 mg/day lycopene. Pre- and posttreatment biopsies were immunostained and digitally scored. Serum lycopene was determined by LC-MS-MS. In secondary analyses, pathologists blindly reviewed each biopsy to score histological features. Fifty-eight men completed the trial. Serum lycopene increased 0.55 µmol/L with treatment and declined 0.29 µmol/L with placebo. We observed no meaningful differences in PSA, IGF-1, or IGF binding protein 3 concentrations between groups, nor any differences in expression of MCM-2 or p27 in epithelial nuclei. Prevalences of cancer, HGPIN, atrophy, or inflammation posttreatment were similar; however, more extensive atrophy and less extensive HGPIN was more common in the lycopene group. Despite large differences in serum lycopene following intervention, no treatment effects were apparent on either the serum or benign tissue endpoints. Larger studies are warranted to determine whether changes observed in extent of HGPIN and focal atrophy can be replicated.

Diet and prostate cancer - a holistic approach to management.

There is now increasing evidence from epidemiologic surveys and from laboratory, intervention, and case-control studies that diet and lifestyle plays a crucial role in prostate cancer biology and tumorigenesis. This applies to both the development and progression of prostate cancer, although in many cases the specific initiating factors in the diet are poorly understood. Conversely, many nutrients and herbs also show significant promise in helping to treat prostate cancer by slowing progression and reducing recurrence, ultimately reducing the risk of morbidity and mortality from the disease. Furthermore for all grades of prostate cancer, nutritional interventions complement conventional treatment to improve response and quality of life. Slowing or even reversing the progression of, high-grade prostate intraepithelial neoplasia [HGPIN]). with chemo-preventative agents could be the best primary defense against prostate cancer, preventing it from occurring in the first place. The information given in this review about prostate cancer chemoprevention summarizes the key evidence for the role of different dietary components and their effect on prostate cancer prevention and progression. Most nutritional chemoprevention agents also have the added benefit of being beneficial for the cardiovascular system, bone health and for the prevention of other cancers.

Dietary feeding of dibenzoylmethane inhibits prostate cancer in transgenic adenocarcinoma of the mouse prostate model.

Dibenzoylmethane (DBM), a minor beta-diketone constituent of licorice, has been shown to exhibit antineoplastic effects in prostate cancer cell lines by induction of cell cycle arrest and regulation of androgen receptor expression. In the present study, we investigated the in vitro and in vivo efficacy of DBM using TRAMP-C1 cell lines and TRAMP mice. DBM was found to arrest TRAMP-C1 cells at G(2)-M phase of cell cycle and suppressed phosphorylated retinoblastoma, cyclin D1, and cyclin A. Importantly, DBM was found to be equally effective in suppression of prostate tumor progression in TRAMP mice. At 8 or 12 weeks of age, mice were fed control or 1% DBM-supplemented diets until 24 weeks of age. Our results show that DBM-fed groups had a lower incidence of palpable tumor and high-grade prostatic intraepithelial neoplasia. Subsequent mechanistic studies show that the expression of phosphorylated retinoblastoma, c-myc, cyclin D1, cyclin A, phosphorylated Akt, phosphorylated PDK-1, and phosphorylated S6 was significantly reduced by DBM. Our findings suggest that DBM blocks the growth and progression of prostate cancer in TRAMP mice via modulation of tumor cell cycle regulation and therefore merits its consideration for future clinical intervention of human prostate cancer.

Effect of nutritional supplement challenge in patients with isolated high-grade prostatic intraepithelial neoplasia.

OBJECTIVES: To investigate, through a prospective follow-up study, the effects of a dietary supplementation challenge in men with isolated high-grade prostatic intraepithelial neoplasia (HGPIN). METHODS: The effects of a 6-month supplementation challenge with selenium, vitamin E, and soy isoflavonoids in men diagnosed with isolated HGPIN on biopsy were evaluated. A total of 100 patients entered the study. Of the 100 men, 29 were excluded because they refused additional biopsies or were noncompliant with the protocol, 71 underwent repeat biopsies at 3 months, and 58 underwent a third set at 6 months. The prostate-specific antigen (PSA) level was recorded at inclusion and before each set of biopsies. The study endpoint was defined as the diagnosis of PCa at 3 months or the histopathologic status at 6 months. RESULTS: At the study endpoint, PCa had been found in 24 men (33.8%), HGPIN in 34 (47.9%), and no HGPIN or carcinoma in 13 (18.3%). The PCa risk throughout the study period was 25.0% in the group with a stable or decreasing PSA level (n = 48, 67.6%) and 52.2% in the group with an increasing PSA level (n = 23, 32.4%). This difference was statistically significant (P = 0.0458). Isolated HGPIN remaining at the first repeat biopsy and the percentage of initial cores with HGPIN were significant predictors of PCa at additional biopsies. CONCLUSIONS: The results of our study have shown that a decrease in the PSA level while taking a selenium, vitamin E, and soy isoflavonoids supplement predicts for a significantly lower risk of PCa in future biopsies. The percentage of initial biopsy cores with HGPIN and isolated HGPIN remaining at the first repeat biopsy are significant predictors of PCa in future biopsies.