Tomato and soy products are hypothesized to reduce the risk of prostate cancer or enhance efficacy of therapy. A study was completed to determine if men with active prostate cancer will adhere to a dietary intervention rich in tomato products and a soy protein supplement men (n = 41) with recurrent, asymptomatic prostate cancer were randomized among 2 groups: Group A (n = 20) consumed tomato products (no soy) for Weeks 0 through 4, targeting a minimum of 25 mg of lycopene/day. Group B (n = 21) consumed soy (no tomatoes) for Weeks 0 through 4, providing 40 g of soy protein/day.
View Article and Find Full Text PDFBackground: Characterization of molecular events during N-methyl-N-nitrosourea (MNU)-induced rat prostate carcinogenesis enhances the utility of this model for the preclinical assessment of preventive strategies. Androgen independence is typical of advanced human prostate cancer and may occur through multiple mechanisms including the loss of androgen receptor (AR) expression and the activation of alternative signaling pathways.
Methods: We examined the interrelationships between AR and p-AKT expression by immunohistochemical staining during MNU-androgen-induced prostate carcinogenesis in male Wistar-Unilever rats.
Mounting evidence over the past decade suggests that the consumption of fresh and processed tomato products is associated with reduced risk of prostate cancer. The emerging hypothesis is that lycopene, the primary red carotenoid in tomatoes, may be the principle phytochemical responsible for this reduction in risk. A number of potential mechanisms by which lycopene may act have emerged, including serving as an important in vivo antioxidant, enhancing cell-to-cell communication via increasing gap junctions between cells, and modulating cell-cycle progression.
View Article and Find Full Text PDFArch Biochem Biophys
August 2004
Prostate cancer is the most frequently diagnosed non-cutaneous cancer and is the second leading cause of cancer death in American men. The focus of this review is to define the relationship between hormonal (testosterone/estrogens) stimulation of chronic inflammation, generation of reactive oxygen species (ROS), and uncontrolled prostate cell proliferation, and review putative dietary chemoprevention strategies that focus on these processes. It has been proposed that elevated estrogen in men who already have high blood testosterone are at high risk for prostate cancer.
View Article and Find Full Text PDFEpidemiologic evidence suggests a possible role for lycopene-rich foods in the prevention of prostate cancer and cardiovascular disease. Despite active research in disease reduction, there is a paucity of information on the absorption, biodistribution and metabolism of lycopene. The aim of this study was to evaluate the biodistribution of 14C-lycopene (specific activity, 1.
View Article and Find Full Text PDFBackground: Consumption of tomato products or lycopene and energy restriction have been hypothesized to reduce the risk of human prostate cancer. We investigated the effects of these dietary variables in a rat model of prostate carcinogenesis.
Methods: Male rats (n = 194) treated with N-methyl-N-nitrosourea and testosterone to induce prostate cancer were fed diets containing whole tomato powder (13 mg lycopene/kg diet), lycopene beadlets (161 mg lycopene/kg diet), or control beadlets.
J Biochem Mol Toxicol
January 2004
Exposure to ultraviolet radiation (UVR) is a known risk factor for cataract, but the molecular mechanisms involved have not been elucidated. We hypothesized that exposure to UVR would modulate the activation of nuclear factor kappa-B (NF-kappa B) within the human lens epithelium, since NF-kappa B is a key regulator of cellular responses to UVR stress in other cell types. Human lens epithelial (HLE) cells were exposed to acute physiological doses of ultraviolet A (UVAR), B (UVBR), C (UVCR) radiation, or interleukin-1 beta (IL-1 beta) and NF-kappa B activation was measured by electrophoretic shift assay (EMSA).
View Article and Find Full Text PDFLycopene, the predominant carotenoid in tomatoes, is among the major carotenoids in serum and tissues of Americans. Although about 90% of the lycopene in dietary sources is found in the linear, all-trans conformation, human tissues contain mainly cis-isomers. Several research groups have suggested that cis-isomers of lycopene are better absorbed than the all-trans form because of the shorter length of the cis-isomer, the greater solubility of cis-isomers in mixed micelles, and/or as a result of the lower tendency of cis-isomers to aggregate.
View Article and Find Full Text PDFProliferation, apoptosis and angiogenesis are critical biologic processes altered during carcinogenesis. Surrogate biomarkers of these processes represent potential intermediate endpoints for short-term intervention studies with preventive and therapeutic agents. We examined the interrelationships among these processes during prostate carcinogenesis induced by N-methyl-N-nitrosourea (MNU) in male Wistar-Unilever rats.
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