A dietary tomato supplement prevents prostate cancer in TRAMP mice

Adherence to the Mediterranean Diet and its association with gastric cancer: health benefits from a Planeterranean perspective

The Mediterranean Diet (MD) has garnered increasing attention for its potential protective effects against gastric cancer (GC). The MD's rich content of antioxidants, polyphenols, and other bioactive compounds contributes to its ability to modulate gene expression, inhibit tumor growth, and regulate apoptosis. Studies have shown significant reductions in inflammatory markers such as C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) among individuals adhering to the MD, suggesting its pivotal role in mitigating chronic inflammation-associated with cancer development. Furthermore, the MD's anti-angiogenic properties, particularly in components like olive oil, red wine, fish, and tomatoes, offer promising avenues for reducing GC risk by inhibiting tumor angiogenesis. Additionally, the MD's influence on intestinal microbiota composition underscores its potential in maintaining immune homeostasis and reducing systemic inflammation, factors crucial in GC prevention. Despite challenges such as variability in dietary adherence scoring systems and the need for further gender and geographical-specific studies, evidence supports the MD as a cost-effective and holistic approach to GC prevention. Emphasizing the role of nutrition in public health is a promising strategy with broad implications for global health and cancer prevention initiatives. Therefore, this review explores the multifaceted impacts of the MD on GC prevention, delving into its anti-inflammatory, anti-angiogenic, and molecular mechanisms.

Orchestration of miRNA Patterns by Testosterone and Dietary Tomato Carotenoids during Early Prostate Carcinogenesis in TRAMP Mice

BACKGROUND

The integrative effects of prostate cancer risk factors, such as diet and endocrine status, on cancer-associated miRNA expression are poorly defined.

OBJECTIVES

This study aimed to define the influence of androgens and diet (tomato and lycopene) on prostatic miRNA expression during early carcinogenesis in the transgenic adenocarcinoma of the mouse prostate (TRAMP) model.

METHODS

Wild type (WT) and TRAMP mice were fed control, tomato-containing, or lycopene-containing diets from 4 to 10 weeks of age. Mice underwent either sham (intact) or castration surgery at 8 wk, and half of the castrated mice received testosterone (2.5 mg/kg body weight/d) at 9 wk. Mice were killed at 10 wk, and dorsolateral prostate expression of 602 miRNAs was assessed.

RESULTS

We detected expression of 88 miRNAs (15% of 602), all of which were present in the TRAMP, in comparison with 49 miRNAs being detectable (8%) in WT. Expression of 61 miRNAs differed by TRAMP genotype, with the majority upregulated in TRAMP. Of the 61 miRNAs, 42 were responsive to androgen status. Diet affected 41% of the miRNAs, which differed by genotype (25/61) and 48% of the androgen-sensitive miRNAs (20/42), indicating overlapping genetic and dietary influences on prostate miRNAs. Tomato and lycopene feeding influenced miRNAs previously associated with the regulation of androgen (miR-145 and let-7), MAPK (miR-106a, 204, 145/143, and 200b/c), and p53 signaling (miR-125 and miR-98) pathways.

CONCLUSIONS

Expression of miRNAs in early prostate carcinogenesis is sensitive to genetic, endocrine, and diet drivers, suggesting novel mechanisms by which tomato and lycopene feeding modulate early prostate carcinogenesis.

Improving Whole Tomato Transformation for Prostate Health: Benign Prostate Hypertrophy as an Exploratory Model

It is well-established that the beneficial properties of single phytonutrients can be better attained when they are taken with the complex of the molecules present in their natural milieu. Tomato, the fruit providing the most comprehensive complex of prostate-health-preserving micronutrients, has been shown to be superior to its single-nutrient counterparts in decreasing the incidence of age-related prostate diseases. Herein, we describe a novel tomato food supplement enriched with olive polyphenols, containing cis-lycopene concentrations far exceeding those present in industry-produced tomato commodities. The supplement, endowed with antioxidant activity comparable to that of N-acetylcysteine, significantly reduced, in experimental animals, the blood levels of prostate-cancer-promoting cytokines. In prospective, randomized, double-blinded, placebo-controlled studies performed on patients affected by benign prostatic hyperplasia, its uptake significantly improved urinary symptoms and quality of life. Therefore, this supplement can complement and, in some cases, be an alternative to current benign prostatic hyperplasia management. Furthermore, the product suppressed carcinogenesis in the TRAMP mouse model of human prostate cancer and interfered with prostate cancer molecular signaling. Thus, it may offer a step forward in exploring the potential of tomato consumption to delay or prevent the onset of age-related prostate diseases in high-risk individuals.

Development of the whole tomato and olive-based food supplement enriched with anti-platelet aggregating nutrients

Background

Platelet dysfunctions are shared by cardiovascular diseases and a wide range of inflammatory diseases.

Aims

To determine the ability of a new whole tomato-based food supplement (WTBFS) containing carotenoid and olive polyphenols to inhibit platelet aggregation.

Methods

Aggregation was evaluated in platelet-rich plasma using microtiter plates and a plate reader.

Results

Platelets treated with WTBFS showed a >70% reduction of 5 µM adenosine diphosphate (ADP)-induced platelet aggregation; at 10 µM of ADP, the inhibitory effect of WTBFS was reduced of about 50%. Similarly, 78% and 48% reduction were obtained using 5 µg/mL and 10 µg /mL of collagen as an agonist

Conclusion

Since the compounds in WTBFS share the ability to inhibit STAT3, the inhibition of its signaling pathway may represent the mechanism underlying the antiplatelet activities. The activity of a lipophilic solution prepared from WTBS was in vitro tested on the platelet aggregation in response to ADP agonists and Collagen.

Tomatoes, Lycopene, and Prostate Cancer: What Have We Learned from Experimental Models?

Human epidemiology suggests a protective effect of tomatoes or tomato phytochemicals, such as lycopene, on prostate cancer risk. However, human epidemiology alone cannot reveal causal relations. Laboratory animal models of prostate cancer provide opportunities to investigate hypotheses regarding dietary components in precisely controlled, experimental systems, contributing to our understanding of diet and cancer risk relations. We review the published studies evaluating the impact of tomatoes and/or lycopene in preclinical models of prostate carcinogenesis and tumorigenesis. The feeding of tomatoes or tomato components demonstrates anti-prostate cancer activity in both transplantable xenograft models of tumorigenesis and models of chemically- and genetically-driven carcinogenesis. Feeding pure lycopene shows anticancer activity in most studies, although outcomes vary by model system, suggesting that the impact of pure lycopene can depend on dose, duration, and specific carcinogenic processes represented in different models. Nonetheless, studies with the transgenic adenocarcinoma of the mouse prostate (TRAMP) model of carcinogenesis typically demonstrate similar bioactivity to that of tomato feeding. In general, interventions that commence earlier in carcinogenesis and are sustained tend to be more efficacious. Accumulated data suggest that lycopene is one, but perhaps not the only, anticancer bioactive compound in tomatoes. Although it is clear that tomatoes and lycopene have anti-prostate cancer activity in rodent models, major knowledge gaps remain in understanding dose-response relations and molecular mechanisms of action. Published and future findings from rodent studies can provide guidance for translational scientists to design and execute informative human clinical trials of prostate cancer prevention or in support of therapy.

β-Carotene Oxygenase 2 Genotype Modulates the Impact of Dietary Lycopene on Gene Expression during Early TRAMP Prostate Carcinogenesis

BACKGROUND

Epidemiologic studies suggest lycopene and tomato intake are inversely associated with human prostate cancer incidence. In the genetically driven murine prostate carcinogenesis model transgenic adenocarcinoma of the mouse prostate (TRAMP), prostate cancer is inhibited by feeding of lycopene or tomatoes, and these effects are modulated by the β-carotene oxygenase 2 (Bco2) genotype.

OBJECTIVE

We sought insight into this interaction through evaluation of prostate gene expression patterns during early TRAMP carcinogenesis.

METHODS

Three-week-old TRAMP/+ or TRAMP/- × Bco2+/+ or Bco2-/- mice were fed a control, lycopene beadlet, or 10% tomato powder-containing semipurified diet (providing 0, 384 and 462 mg lycopene/kg diet, respectively) for 5 wk. Gene expression patterns were evaluated by prostate cancer- and cholesterol and lipoprotein metabolism-focused arrays at age 8 wk.

RESULTS

The TRAMP genotype profoundly alters gene expression patterns, specifically inducing pathways associated with cell survival [z-score = 2.09, -log(P value) = 29.2, p53 signaling (z-score 1.13, -log(P value) = 13.5], and phosphatidylinositol-3 kinase (PI3K)/protein kinase B (AKT) signaling [z-score = 0.302, -log(P value) = 12.1], while repressing phosphatase and tensin homolog (PTEN) signaling [(z-score = -0.905, -log(P value) = 12.3], cholesterol synthesis [z-score = -1.941, -log(P-value) = 26.2], and LXR/RXR pathway activation [z-score = -1.941, -log(P value) = 23.1]. In comparison, lycopene- and tomato-feeding modestly modulate strong procarcinogenic TRAMP signaling. Lycopene decreased gene expression related to carcinogenesis [ Nkx3-1(NK3 homeobox 1)], tomato feeding increased expression of a gene involved in circadian regulation [Arntl (aryl hydrocarbon receptor nuclear translocator like)], and tomato and/or lycopene increased expression of genes involved in lipid metabolism [Fasn (fatty acid synthase), Acaca(acetyl-CoA carboxylase alpha), Srebf1 (sterol regulatory element binding transcription factor 1), Hmgcr (3-hydroxy-3-methylglutaryl-coA reductase), and Ptgs1 (prostaglandin-endoperoxide synthase 1)] (all P < 0.05). The impact of Bco2 genotype was limited to a subset of lycopene-impacted genes [Apc (adenomatous polyposis coli), Mto1 (mitochondrial TRNA translation optimization 1), Nfkb1 (nuclear factor kappa B subunit 1), andRbm39 (RNA binding motif protein 39)].

CONCLUSIONS

The TRAMP genotype strongly impacts procarcinogenic gene expression prior to emergence of histopathologic disease. Dietary tomato and lycopene modestly temper these processes, while Bco2 genotype has a limited impact at this early stage. These observed patterns provide insight into the complex interactions between a dietary variable, here tomatoes and lycopene, genes impacting nutrient metabolism, and their modulating influences on oncogene-driven prostate carcinogenesis. These findings provide further mechanistic support, consistent with cancer outcomes in rodents experiments and human epidemiologic studies.

Tomato and Olive Bioactive Compounds: A Natural Shield against the Cellular Effects Induced by β-Hexachlorocyclohexane-Activated Signaling Pathways

The β-isomer of hexachlorocyclohexane (β-HCH) is a globally widespread pollutant that embodies all the physicochemical characteristics of organochlorine pesticides, constituting an environmental risk factor for a wide range of noncommunicable diseases. Previous in vitro studies from our group disclosed the carcinogenic potential of β-HCH, which contributes to neoplastic transformation by means of multifaceted intracellular mechanisms. Considering the positive evidence regarding the protective role of natural bioactive compounds against pollution-induced toxicity, micronutrients from olive and tomato endowed with the capability of modulating β-HCH cellular targets were tested. For this purpose, the solution obtained from a patented food supplement (No. EP2851080A1), referred to as Tomato and Olive Bioactive Compounds (TOBC), was administered to the androgen-sensitive prostate cancer cells LNCaP and different biochemical and cellular assays were performed to evaluate its efficiency. TOBC shows a dose-dependent significant chemoprotection by contrasting β-HCH-induced intracellular responses such as STAT3 and AhR activation, disruption of AR signaling, antiapoptotic and proliferative activity, and increase in ROS production and DNA damage. These experimental outcomes identified TOBC as a suitable functional food to be included in a diet regimen aimed at defending cells from β-HCH negative effects, recommending the development of tailored enriched formulations for exposed individuals.

Scientometric and Methodological Analysis of the Recent Literature on the Health-Related Effects of Tomato and Tomato Products

The health benefits of tomato, a vegetable consumed daily in human diets, have received great attention in the scientific community, and a great deal of experiments have tested their utility against several diseases. Herein, we present a scientometric analysis of recent works aimed to estimate the biological effects of tomato, focusing on bibliographic metadata, type of testers, target systems, and methods of analysis. A remarkably variable array of strategies was reported, including testers obtained by standard and special tomatoes, and the use of in vitro and in vivo targets, both healthy and diseased. In vitro, 21 normal and 36 cancer human cell lines derived from 13 different organs were used. The highest cytotoxic effects were reported on cancer blood cells. In vivo, more experiments were carried out with murine than with human systems, addressing healthy individuals, as well as stressed and diseased patients. Multivariate analysis showed that publications in journals indexed in the agriculture category were associated with the use of fresh tomatoes; conversely, medicine and pharmacology journals were associated with the use of purified and formulate testers. Studies conducted in the United States of America preferentially adopted in vivo systems and formulates, combined with blood and tissue analysis. Researchers in Italy, China, India, and Great Britain mostly carried out in vitro research using fresh tomatoes. Gene expression and proteomic analyses were associated with China and India. The emerging scenario evidences the somewhat dichotomic approaches of plant geneticists and agronomists and that of cell biologists and medicine researchers. A higher integration between these two scientific communities would be desirable to foster the assessment of the benefits of tomatoes to human health.

Improvement of urinary tract symptoms and quality of life in benign prostate hyperplasia patients associated with consumption of a newly developed whole tomato-based food supplement: a phase II prospective, randomized double-blinded, placebo-controlled study

Background

Benign prostatic hyperplasia (BPH) is the most common urologic disease among elderly men. The diagnosis of BPH is usually driven by lower urinary tract symptoms (LUTS) that can significantly affect patients’ quality of life. This phase II prospective, randomized double-blinded, placebo-controlled study aimed to determine the efficacy and safety of a novel whole tomato-based food supplement on LUTS of patients diagnosed with BPH.

Methods

Forty consecutive patients with histologically proved BPH were randomized 1:1 to receive daily for 2 months a sachet (5 g) of a newly developed whole tomato food supplement (WTFS) (treatment = Group A) or placebo (Group B). Patients were asked to fill the International Prostatic Symptom Score (IPSS) questionnaire before and after treatment.

Results

All but 1 patient in Group B successfully completed the scheduled regimen. No side effects were recorded. Unlike placebo, treatment significantly reduced (P < 0.0002) LUTS since mean IPSS decreased from 9.05 ± 1.15 to 7.15 ± 1.04 (paired t-test, two-tailed P-value < 0.001), and improved life quality (P < 0.0001). A trend toward a reduction of total PSA levels was observed in WTFS treated patients (8.98 ng/mL ± 1.52 vs 6.95 ± 0.76, P = 0.065), with changes being statistically significant only in the subgroup of patients with baseline levels above 10 ng/mL (18.5 ng/mL ± 2.7 vs 10.3 ± 2.1, P = 0.009).

Conclusions

The new WTFS may represent a valid option for the treatment of symptomatic BPH patients. Unlike pharmacological treatments, the supplement is side effects free and highly accepted among patients.

The Mediterranean Diet, a Rich Source of Angiopreventive Compounds in Cancer

Diet-based chemoprevention of cancer has emerged as an interesting approach to evade the disease or even target its early phases, reducing its incidence or slowing down tumor progression. In its basis in the essential role of angiogenesis for tumor growth and metastasis, angioprevention proposes the use of inhibitors of angiogenesis in cancer prevention. The anti-angiogenic potential exhibited by many natural compounds contained in many Mediterranean diet constituents makes this dietary pattern especially interesting as a source of chemopreventive agents, defined within the angioprevention strategy. In this review, we focus on natural bioactive compounds derived from the main foods included in the Mediterranean diet that display anti-angiogenic activity, as well as their possible use as angiopreventive agents.

Systemic alkalinisation delays prostate cancer cell progression in TRAMP mice

The microenvironment of solid tumours is extremely acidic and this condition arises since the precancerous stage. This acidic milieu could therefore provide a useful target for both prophylactic and therapeutic approaches. In TRAMP transgenic mice, an in vivo model of prostate adenocarcinoma (AC), oral administration of alkaline water was devoid of unwanted side effects, and when started from an early age was as effective as NaHCO₃ in significantly delaying tumour progression, while when started when prostate tumours were already present, a nonstatistically significant trend in the same direction was detected. These findings indicate that the use of alkalinizing drugs should be considered for chemoprevention and, in association with standard chemotherapy, for treatment of human prostate AC.

β-Carotene 9',10' Oxygenase Modulates the Anticancer Activity of Dietary Tomato or Lycopene on Prostate Carcinogenesis in the TRAMP Model

The hypothesis that dietary tomato consumption or the intake of the carotenoid lycopene inhibits prostate cancer arose from epidemiologic studies and is supported by preclinical rodent experiments and in vitro mechanistic studies. We hypothesize that variation in activity of carotenoid cleavage enzymes, such as β-carotene 9',10'-oxygenase (BCO2), may alter the impact of dietary tomato and lycopene on prostate carcinogenesis and therefore examined this relationship in the TRAMP model. Starting at 3 weeks of age, TRAMP:Bco2^+/+ and TRAMP:Bco2^-/- mice were fed either AIN-93G control, or semipurified diets containing 10% tomato powder or 0.25% lycopene beadlets until 18 weeks of age. Both tomato- and lycopene-fed TRAMP:Bco2^-/- mice had significantly greater serum concentrations of total, 5-cis, other cis, and all-trans lycopene than TRAMP:Bco2^+/+ mice. Tomato- and lycopene-fed mice had a lower incidence of prostate cancer compared with the control-fed mice. Although Bco2 genotype alone did not significantly change prostate cancer outcome in the control AIN-93G-fed mice, the abilities of lycopene and tomato feeding to inhibit prostate carcinogenesis were significantly attenuated by the loss of Bco2 (P_interaction = 0.0004 and 0.0383, respectively). Overall, dietary tomato and lycopene inhibited the progression of prostate cancer in TRAMP in a Bco2 genotype-specific manner, potentially implicating the anticancer activity of lycopene cleavage products. This study suggests that genetic variables impacting carotenoid metabolism and accumulation can impact anticancer activity and that future efforts devoted to understanding the interface between tomato carotenoid intake, host genetics, and metabolism will be necessary to clearly elucidate their interactive roles in human prostate carcinogenesis. Cancer Prev Res; 10(2); 161-9. ©2016 AACR.

Low-lycopene containing tomato powder diet does not protect against prostate cancer in TRAMP mice

Previously, tomato powder (TP) diets initiated postweaning have been shown to be effective in reducing prostate cancer in the transgenic adenocarcinoma of the mouse prostate (TRAMP) model. The TRAMP model develops and progresses through all stages of carcinogenesis similarly to humans. We hypothesized that a 10% TP diet intervention after puberty would reduce carcinogenesis at 12, 16, and 20 weeks of age in TRAMP mice. Eight-week-old male C57BL/6 X FVB F1 TRAMP mice were randomized to consume either an AIN-93G + 10% TP diet (n = 90) or the AIN-93G control diet (n = 88) and randomized to 1 of 3 end point ages: 12 (n = 59), 16 (n = 60), or 20 (n = 59) weeks of age. There was no difference between diets in overall cancer incidence at any time point. However, at 16 weeks of age, TP significantly increased high-grade PIN (P = .014) and significantly decreased poorly differentiated (P = .024) lesions compared with the control diet suggesting a delay in the progression of prostate cancer. Two variables that may explain the modest effect of TP in this study are as follows: the low amount of lycopene in the TP diet (12.3 ppm) and the timing of the intervention (8 weeks of age). The TP diet contained 30-fold less lycopene than previous studies in our laboratory. In addition, the initiation of the diet intervention time of 8 weeks of age instead of 4 weeks of age may have been too late in cancer progression to substantially impact carcinogenesis. In conclusion, a low-lycopene TP intervention failed to reduce carcinogenesis in TRAMP mice.

Dietary tomato and lycopene impact androgen signaling- and carcinogenesis-related gene expression during early TRAMP prostate carcinogenesis

Consumption of tomato products containing the carotenoid lycopene is associated with a reduced risk of prostate cancer. To identify gene expression patterns associated with early testosterone-driven prostate carcinogenesis, which are impacted by dietary tomato and lycopene, wild-type (WT) and transgenic adenocarcinoma of the mouse prostate (TRAMP) mice were fed control or tomato- or lycopene-containing diets from 4 to 10 weeks of age. Eight-week-old mice underwent sham surgery, castration, or castration followed by testosterone repletion (2.5 mg/kg/d initiated 1 week after castration). Ten-week-old intact TRAMP mice exhibit early multifocal prostatic intraepithelial neoplasia. Of the 200 prostate cancer-related genes measured by quantitative NanoString, 189 are detectable, 164 significantly differ by genotype, 179 by testosterone status, and 30 by diet type (P < 0.05). In TRAMP, expression of Birc5, Mki67, Aurkb, Ccnb2, Foxm1, and Ccne2 is greater compared with WT and is decreased by castration. In parallel, castration reduces Ki67-positive staining (P < 0.0001) compared with intact and testosterone-repleted TRAMP mice. Expression of genes involved in androgen metabolism/signaling pathways is reduced by lycopene feeding (Srd5a1) and by tomato feeding (Srd5a2, Pxn, and Srebf1). In addition, tomato feeding significantly reduced expression of genes associated with stem cell features, Aldh1a and Ly6a, whereas lycopene feeding significantly reduced expression of neuroendocrine differentiation-related genes, Ngfr and Syp. Collectively, these studies demonstrate a profile of testosterone-regulated genes associated with early prostate carcinogenesis that are potential mechanistic targets of dietary tomato components. Future studies on androgen signaling/metabolism, stem cell features, and neuroendocrine differentiation pathways may elucidate the mechanisms by which dietary tomato and lycopene impact prostate cancer risk.

Extra virgin olive oil: from composition to "molecular gastronomy"

The aim of this chapter is to provide a brief overview of the recent results of studies on extra virgin olive oil (EVOO) and its interactions with other food ingredients during cooking, to highlight basic molecular aspects of the "magic" of EVOO and its role in Mediterranean gastronomy. The use of raw EVOO added to foods after cooking (or as a salad oil) is the best way to express the original flavour and to maximize the intake of natural antioxidants and compounds related to positive effects on human health (hypotensive, anti-inflammatory, and anti-cancerogenic, among others). EVOO, however, also exhibits its protective properties during/after cooking. Different chemical interactions between biophenolic compounds and other food ingredients (water, milk proteins, carotenoids of tomato, omega-3 polyunsaturated fatty acids in canned-in-oil fish and meat or fish proteins) occur. Even during cooking, EVOO exhibits strong antioxidant properties and influences the overall flavour of cooked foods. The physical (partitioning, emulsion) and chemical (hydrolysis, covalent binding, antioxidant properties) phenomena occurring during cooking of EVOO are discussed with emphasis on the changes in the sensory (bitterness and fruity flavour) and nutritional qualities of some traditional Mediterranean foods. In particular, tomato-oil interactions during cooking, fish canning in EVOO, meat marinated in EVOO before cooking and roasting and frying in EVOO are examined. The interactions between EVOO antioxidants and flavours with milk proteins are also briefly discussed.

[Pharmaco and diet based prostate cancer prevention]

In 2010, in France, 8,790 men died from prostate cancer despite a low and decreasing mortality rate. The individual risk/benefit ratio of prostate cancer screening is the focus of controversy and currently not in favor of a systematic screening program. Therefore, only prevention could reduce incidence, side effects of treatment and related mortality. Interestingly, prostate cancer prevention is also a field of controversy mainly about 5-alpha-reductase inhibitors. However, it could be expected that pharmaco- or diet-based prevention will be a huge tool for cancer control, even more for prostate cancer burden. This review comprehensively analyses which molecules or compounds could be used in preventive trials. With regard to pharmaco-prevention, three different kinds of drugs could be identified. First drugs, which aim at mainly or even solely reduce prostate cancer risk such as 5-alpha-reductase inhibitors and selective estrogen receptor modulators. Drugs, which aim at wider preventive impact such as: nonsteroidal anti-inflammatory drugs or difluoromethylornithine. Lastly, drugs for which reducing prostate cancer incidence is merely a side effect such as statins, metformin or histones desacetylase inhibitors. With regard to diet-based prevention, two main approaches could be identified: aliments and nutriments, on one hand, and vitamin and minerals, on the other. Interestingly if compounds reach experimental plausibility, natural foods or even global diet seem to have a higher impact. Lastly, besides assessment of efficacy, effectiveness required the critical step of compliance, which might actually be the weakest link of the prevention chain.

The interactions of dietary tomato powder and soy germ on prostate carcinogenesis in the TRAMP model

The interactions between bioactive-rich food components within a complex human diet for the inhibition of prostate carcinogenesis are largely unknown and difficult to quantify in humans. Tomato and soy products have each shown anti-prostate cancer (PCa) activity in laboratory studies. The objective of this study was to determine the efficacy of dietary tomato and soy germ, alone and in combination, for the inhibition of PCa in the transgenic adenocarcinoma of the mouse prostate (TRAMP) model. At 4 weeks of age, male C57BL/6 × FVB TRAMP mice (n = 119) were randomized to consume: AIN-93G control, 10% whole tomato powder (TP), 2% soy germ powder (SG), or 10% tomato powder with 2% soy germ powder (TP+SG) for 14 weeks. One hundred percent of mice fed the control diet had PCa, whereas PCa incidence was significantly lower in mice consuming TP (61%, P < 0.001), SG (66%, P < 0.001), and TP+SG (45%, P < 0.001). Although the protection offered by the combination of TP and SG was not synergistic, it was the most effective intervention. TP, SG, and TP+SG increased apoptotic index (AI) and modestly reduced the proliferative index (PI) in the prostate epithelium of TRAMP mice exhibiting primarily prostatic intraepithelial neoplasia. The dramatic reduction in the PI/AI ratio by the dietary interventions suggests that the control mice experience a stronger stimulus for malignant progression in the prostate microenvironment. Maximally effective and safe strategies for PCa prevention may result from optimizing combinations of nutrients and bioactives through an orchestration of dietary patterns.

Xanthohumol impairs human prostate cancer cell growth and invasion and diminishes the incidence and progression of advanced tumors in TRAMP mice

Despite recent advances in understanding the biological basis of prostate cancer, management of the disease, especially in the phase resistant to androgen ablation, remains a significant challenge. The long latency and high incidence of prostate carcinogenesis provides the opportunity to intervene with chemoprevention to prevent or eradicate prostate malignancies. In this study, we have used human hormone-resistant prostate cancer cells, DU145 and PC3, as an in vitro model to assess the efficacy of xanthohumol (XN) against cell growth, motility and invasion. We observed that treatment of prostate cancer cells with low micromolar doses of XN inhibits proliferation and modulates focal adhesion kinase (FAK) and AKT phosphorylation leading to reduced cell migration and invasion. Oxidative stress by increased production of reactive oxygen species (ROS) was associated with these effects. Transgenic adenocarcinoma of the mouse prostate (TRAMP) transgenic mice were used as an in vivo model of prostate adenocarcinoma. Oral gavage of XN, three times per week, beginning at 4 wks of age, induced a decrease in the average weight of the urogenital (UG) tract, delayed advanced tumor progression and inhibited the growth of poorly differentiated prostate carcinoma. The ability of XN to inhibit prostate cancer in vitro and in vivo suggests that XN may be a novel agent for the management of prostate cancer.

Prostate cancer and inflammation: the evidence

Chronic inflammation is now known to contribute to several forms of human cancer, with an estimated 20% of adult cancers attributable to chronic inflammatory conditions caused by infectious agents, chronic non-infectious inflammatory diseases and/or other environmental factors. Indeed, chronic inflammation is now regarded as an 'enabling characteristic' of human cancer. The aim of this review is to summarize the current literature on the evidence for a role for chronic inflammation in prostate cancer aetiology, with a specific focus on recent advances regarding the following: (i) potential stimuli for prostatic inflammation; (ii) prostate cancer immunobiology; (iii) inflammatory pathways and cytokines in prostate cancer risk and development; (iv) proliferative inflammatory atrophy (PIA) as a risk factor lesion to prostate cancer development; and (v) the role of nutritional or other anti-inflammatory compounds in reducing prostate cancer risk.

Antioxidants for prostate cancer chemoprevention: challenges and opportunities

Extensive research has led to the firm conclusion that antioxidants protect cells from damage caused by oxidative stress and its associated pathological conditions including inflammation. It has also been established that inflammation is a precursor in neoplastic transformation of the prostate. Although, a vast body of experimental and clinical evidence shows efficacy of antioxidants as preventive strategies for prostate cancer, there is a lack of consistent agreement in outcomes especially from recent large-scale randomized clinical trials. Despite these concerns, our understanding of the preventive mechanisms as well as clinical efficacy and safety data indicate that novel antioxidant therapeutics still hold great promise for prostate cancer chemoprevention. We propose that for effective use of antioxidants for prostate cancer prevention, further high impact translational research is needed with special attention on selecting those patients who will benefit from such intervention. Therefore, it is important to validate predictive biomarkers from successful trials and combine this with knowledge of preclinical characterization of antioxidants (and combinations) that will eventually facilitate the development of 'personalized prostate cancer chemoprevention'. In this review, we briefly describe some common and emerging antioxidants that have shown benefits in preclinical and clinical settings. Above all, we focus on summarizing the progress we made thus far in prostate cancer chemoprevention using antioxidants, the heightened interest and challenges in the future.

Free amino acid and phenolic contents and antioxidative and cancer cell-inhibiting activities of extracts of 11 greenhouse-grown tomato varieties and 13 tomato-based foods

Tomato (Solanum lycopersicum) plants synthesize nutrients, pigments, and bioactive compounds that benefit nutrition and human health. The nature and concentrations of these compounds are strongly influenced by varietal factors such as size and color as well as by processing. To better understand how these factors affect the concentration of nutrients and bioactive compounds, we analyzed 11 Korean tomato varieties grown under the same greenhouse conditions and 13 processed commercial tomato products for free amino acids and amino acid metabolites by HPLC, for individual phenolics by HPLC-MS, for total phenolics by the Folin-Ciocalteu method, for antioxidative activity by the FRAP and DPPH methods, and for cancer cell-inhibiting effects by the MTT assay. We also determined the protein content of the tomatoes by an automated Kjeldahl method. The results show that there is a broad range of bioactive compounds across tomato varieties and products. Small tomatoes had higher contents of bioactive compounds than the large ones. The content of phenolic compounds of processed products was lower than that of fresh tomatoes. Tomato extracts promoted growth in normal liver (Chang) cells, had little effect in normal lung (Hel299) cells, mildly inhibited growth of lung cancer (A549) cells, and first promoted and then, at higher concentrations, inhibited growth in lymphoma (U937) cells. The relationship of cell growth to measured constituents was not apparent. Dietary and health aspects of the results are discussed.