Prostate cancer and diet: food for thought?

Lifestyle factors and prostate-specific antigen

Background:

Increasing prostate cancer awareness has meant that more men are seeking out prostate-specific antigen (PSA) testing than ever before. Prostate cancer is now the most common malignancy in men, affecting one in eight. This article addresses lifestyle factors that may elevate PSA readings.

Methods:

A systematic review of the literature was performed using Medline for studies examining the association of PSA and lifestyle factors, including exercise, diet, sexual function as well as medication use. Further resources were identified from the reference list of retrieved articles.

Results:

Minimal level 1 evidence on the association of PSA with lifestyle factors was identified. Weak and generally inconsistent evidence was found on the effect of cycling and sexual activity. Diabetes and obesity did have inversely proportional effects on PSA values in large cohort studies. There was no evidence for an independent effect of different types of food to PSA. With regard to medications, the greatest impact is from 5-alpha reductase inhibitors, and these are used as a hair-loss treatment. Statins, non-steroidal anti-inflammatory drugs and thiazide diuretics can also have a clinically significant impact on PSA levels but unlikely to alter management.

Discussion:

For a small group of patients, cautious counselling on the factors summarised here before they have their blood tests may prevent undue stress and anxiety, particularly in those with borderline PSA results. Due to the inconsistency of results and lack of level 1a evidence, if there is reasonable suspicion for prostate cancer, a patient should still always be referred to a specialist.

Level of evidence:

Level 4.

The Multifaceted Roles of Diet, Microbes, and Metabolites in Cancer

Many studies performed to date have implicated select microbes and dietary factors in a variety of cancers, yet the complexity of both these diseases and the relationship between these factors has limited the ability to translate findings into therapies and preventative guidelines. Here we begin by discussing recently published studies relating to dietary factors, such as vitamins and chemical compounds used as ingredients, and their contribution to cancer development. We further review recent studies, which display evidence of the microbial-diet interaction in the context of cancer. The field continues to advance our understanding of the development of select cancers and how dietary factors are related to the development, prevention, and treatment of these cancers. Finally, we highlight the science available in the discussion of common misconceptions with regards to cancer and diet. We conclude this review with thoughts on where we believe future research should focus in order to provide the greatest impact towards human health and preventative medicine.

Serum Levels of Selenium, Zinc, Copper, Manganese, and Iron in Prostate Cancer Patients

Backgrounds

Variations of trace element contents may be associated with several diseases including metabolic disorders, cellular growth disturbance, mutation and tumorigenesis. Prostate cancer is the second most common male cancer worldwide and stand fifth most common male cancer in Saudi Arabia.

Objective

In the present study, Serum levels of selenium, zinc, copper, manganese, and iron were measured in patients with BPH and prostate cancer aiming to explore the association between these elements and prostate cancer.

Patients and Methods

The study included 40 newly diagnosed prostate cancer patients, 22 patients with BPH and 30 healthy male subjects. All participant groups had similar socio-economic levels. Fasting blood samples were collected from all subjects and before any intervention for the patients. Serum PSA concentrations were analyzed by ELIZA and trace elements Se, Zn, Cu, Mn and Fe were measured by ICP-MS.

Results

Serum Se, Zn, and Mn levels of prostate cancer patients were significantly decreased compared to control groups. The levels of serum Cu and Fe were significantly higher in prostate cancer patients than in control groups.

Conclusion

In the present study, an association was noticed between serum trace elements disturbance and prostate cancer. The decreased levels of Se, Zn, and Mn, and increased Cu and Fe levels may play significant roles in the initiation of prostate cancer. However, future prospective studies on the causes of trace elements alteration in prostate cancer patients are needed as well as to illustrate the relation between different prostate cancer stages and trace elements concentrations.

Comparative Analysis of Lycopene Content from Different Tomato-Based Food Products on the Cellular Activity of Prostate Cancer Cell Lines

Lycopene is more bioavailable in processed tomato products than in raw tomatoes, since arrangement of cis-isomers of lycopene during food processing and storage may increase its biological activity. The aim of the study is evaluate the influence of lycopene content from different tomato-based food products (extract, paste, ketchup and sauce) on cell proliferation, cell cycle, and rate of apoptosis of human prostate cancer cell lines. DU-145 and PC-3 cell lines were treated with lycopene content from different tomato-based food products (500-5000 μg/mL) for 96 h. The data showed a decrease in cell viability in both DU-145 and PC-3 cells after treatment with all lycopene extracts from tomato-based food products. Analysis of cell cycle revealed a decrease in the percentage of prostate cancer cells in G0/G1 and G2/M phases after 96 h of treatment when using lycopene content from tomato paste and tomato extract. However, lycopene extracted from tomato sauce and ketchup promoted a decrease in the percentage of cells in G0/G1 phase and an increase in S and G2/M phases after 96 h of treatment. Lycopene content from all of those tomato-based food products also increased apoptosis in both prostate cancer cell lines. In this regard, lycopene has proved to be a potent inhibitor of cell viability, arrest cell cycle and increase the apoptosis in human prostate cancer cells, suggesting an effect in the balance of human prostate cancer cell lines growth.

Dairy Products: Is There an Impact on Promotion of Prostate Cancer? A Review of the Literature

This review of the literature aims to study potential associations between high consumption of milk and/or dairy products and prostate cancer (PC). Literature is scarce, yet there is a direct relationship between mTORC1 activation and PC; several ingredients in milk/dairy products, when in high concentrations, increase signaling of the mTORC1 pathway. However, there are no studies showing an unequivocal relationship between milk products PC initiation and/or progression. Three different reviews were conducted with articles published in the last 5 years: (M1) PC and intake of dairy products, taking into account the possible mTORC1signaling mechanism; (M2) Intake of milk products and incidence/promotion of PC; (M3) mTORC1 activation signaling pathway, levels of IGF-1 and PC; (M4) mTORC pathway and dairy products. Of the 32 reviews identified, only 21 met the inclusion criteria and were analyzed. There is little scientific evidence that directly link the three factors: incidence/promotion of PC, intake of dairy products and PC, and PC and increased mTORC1 signaling. Persistent hyper-activation of mTORC1 is associated with PC promotion. The activity of exosomal mRNA in cellular communication may lead to different impacts of different types of milk and whether or not mammalian milks will have their own characteristics within each species. Based on this review of the literature, it is possible to establish a relationship between the consumption of milk products and the progression of PC; we also found a possible association with PC initiation, hence it is likely that the intake of dairy products should be reduced or minimized in mens' diet.

Duality of estrogen receptor β action in cancer progression

The physiological actions of estrogens are primarily mediated by the nuclear hormone receptors estrogen receptor alpha (ERα) and beta (ERβ). Activities of these nuclear steroid hormone receptors in etiology and progression of many hormone-responsive cancers are well-established, yet the specific role of each receptor, and their various expressed isoforms, in estrogen-responsive cancers remains unclear. Recent advances in nuclear receptor profiling, characterization of expressed splice variants, and the availability of new experimental cancer models, has extended the understanding of the complex interplay between the differentially expressed nuclear estrogen receptors. In this review, we discuss proposed roles of ERβ in several subtypes of cancers that lack significant ERα expression and define current understanding of how different ERs collaborate to regulate cellular processes.

Dietary patterns and prostate cancer risk in Japanese: the Japan Public Health Center-based Prospective Study (JPHC Study)

PURPOSE

The development of prostate cancer may be impacted by environmental factors, including diet. The aim of this study was to evaluate the association between dietary patterns and risk of prostate cancer in a large prospective cohort study among Japanese men.

METHODS

A total of 43,469 men who participated in the Japan Public Health Center-based Prospective Study were followed from 1995 to 1998 to the end of 2012, during which 1,156 cases of prostate cancer were newly identified. Dietary intake was assessed using a validated food frequency questionnaire in the 5-year follow-up survey.

RESULTS

Three major dietary patterns were derived using exploratory factors analysis: prudent, westernized, and traditional dietary patterns. The westernized dietary pattern was associated with a higher risk of total prostate cancer (HR: 1.22; 95% CI 1.00-1.49; p trend = 0.021), localized cancer (HR: 1.24; 95% CI 0.97-1.57; p trend = 0.045), and advanced cancer (HR: 1.23; 95% CI 0.82-1.84; p trend = 0.233). The prudent dietary pattern was associated with a lower risk of total and localized prostate cancer, with respective multivariable HRs for the highest and lowest quintiles of 0.71 (95% CI 0.50-1.02; p trend = 0.037) and 0.63 (95% CI 0.38-1.03; p trend = 0.048) among subjects detected by subjective symptoms. No association was found between the traditional dietary pattern and prostate cancer risk among our subjects.

CONCLUSION

Our results suggest that a western-style diet may lead to a higher risk of prostate cancer in the total population, whereas the prudent diet contributes to a lower risk among subjects detected by subjective symptoms.

An update of research evidence on nutrition and prostate cancer

BACKGROUND

Prostate cancer (PCa) remains a leading cause of mortality in US and other countries. Preclinical and clinical studies have examined the role of nutrition and dietary intake on the incidence and progression of PCa with mixed results.

OBJECTIVE

The objective of this chapter is to provide an update of recent published literature and highlight progress in the field.

MAIN FINDINGS

Low carbohydrate intake, soy protein, ω3 fat, green teas, tomatoes and tomato products and the herbal mixture-zyflamend showed promise in reducing PCa risk or progression. On the contrary, a higher animal fat intake and a higher β-carotene status may increase risk. A "U" shape relationship may exist between folate, vitamin C, vitamin D and calcium with PCa risk. Conclusion Despite the inconclusive findings, the potential for a role of dietary intake for the prevention and treatment of PCa remains promising. Maintaining a healthy body weight and following a healthy dietary pattern including antioxidant rich fruits and vegetables, reduced animal fat and refined carbohydrates, should be encouraged.

CONCLUSION

Despite the inconclusive findings, the potential for a role of dietary intake for the prevention and treatment of PCa remains promising. Maintaining a healthy body weight and following a healthy dietary pattern including antioxidant rich fruits and vegetables, reduced animal fat and refined carbohydrates, should be encouraged.

Precision Nutrition for Targeting Lipid Metabolism in Colorectal Cancer

Cancer is a multistage and multifactorial condition with genetic and environmental factors modulating tumorogenesis and disease progression. Nevertheless, cancer is preventable, as one third of cancer deaths could be avoided by modifying key risk factors. Nutrients can directly affect fundamental cellular processes and are considered among the most important risk factors in colorectal cancer (CRC). Red and processed meat, poultry consumption, fiber, and folate are the best-known diet components that interact with colorectal cancer susceptibility. In addition, the direct association of an unhealthy diet with obesity and dysbiosis opens new routes in the understanding of how daily diet nutrients could influence cancer prognosis. In the “omics” era, traditional nutrition has been naturally evolved to precision nutrition where technical developments have contributed to a more accurate discipline. In this sense, genomic and transcriptomic studies have been extensively used in precision nutrition approaches. However, the relation between CRC carcinogenesis and nutrition factors is more complex than originally expected. Together with classical diet-nutrition-related genes, nowadays, lipid-metabolism-related genes have acquired relevant interest in precision nutrition studies. Lipids regulate very diverse cellular processes from ATP synthesis and the activation of essential cell-signaling pathways to membrane organization and plasticity. Therefore, a wide range of tumorogenic steps can be influenced by lipid metabolism, both in primary tumours and distal metastasis. The extent to which genetic variants, together with the intake of specific dietary components, affect the risk of CRC is currently under investigation, and new therapeutic or preventive applications must be explored in CRC models. In this review, we will go in depth into the study of co-occurring events, which orchestrate CRC tumorogenesis and are essential for the evolution of precision nutrition paradigms. Likewise, we will discuss the application of precision nutrition approaches to target lipid metabolism in CRC.

Correlation between Oxidative Stress, Nutrition, and Cancer Initiation

Inadequate or excessive nutrient consumption leads to oxidative stress, which may disrupt oxidative homeostasis, activate a cascade of molecular pathways, and alter the metabolic status of various tissues. Several foods and consumption patterns have been associated with various cancers and approximately 30-35% of the cancer cases are correlated with overnutrition or malnutrition. However, several contradictory studies are available regarding the association between diet and cancer risk, which remains to be elucidated. Concurrently, oxidative stress is a crucial factor for cancer progression and therapy. Nutritional oxidative stress may be induced by an imbalance between antioxidant defense and pro-oxidant load due to inadequate or excess nutrient supply. Oxidative stress is a physiological state where high levels of reactive oxygen species (ROS) and free radicals are generated. Several signaling pathways associated with carcinogenesis can additionally control ROS generation and regulate ROS downstream mechanisms, which could have potential implications in anticancer research. Cancer initiation may be modulated by the nutrition-mediated elevation in ROS levels, which can stimulate cancer initiation by triggering DNA mutations, damage, and pro-oncogenic signaling. Therefore, in this review, we have provided an overview of the relationship between nutrition, oxidative stress, and cancer initiation, and evaluated the impact of nutrient-mediated regulation of antioxidant capability against cancer therapy.

Analysis of origin and protein-protein interaction maps suggests distinct oncogenic role of nuclear EGFR during cancer evolution

Receptor tyrosine kinase EGFR usually is localized on plasma membrane to induce progression of many cancers including cancers in children (Bodey et al. In Vivo. 2005, 19:931-41), but it contains a nuclear localization signal (NLS) that mediates EGFR nuclear translocation (Lin et al. Nat Cell Biol. 2001, 3:802-8). Here we report that NLS of EGFR has its old evolutionary origin. Protein-protein interaction maps suggests that nEGFR pathways are different from membrane EGFR and EGF is not found in nEGFR network while androgen receptor (AR) is found, which suggests the evolution of prostate cancer, a well-known AR driven cancer, through changes in androgen- or EGF-dependence. Database analysis suggests that nEGFR correlates with the tumor grades especially in prostate cancer patients. Structural predication analysis suggests that NLS can compromise the differential protein binding to EGFR through stretch linkers with evolutionary mutation from N to V. In experiment, elevation of nEGFR but not membrane EGFR was found in castration resistant prostate cancer cells. Finally, systems analysis of NLS and transmembrane domain (TM) suggests that NLS has old origin while NLS neighboring domain of TM has been undergone accelerated evolution. Thus nEGFR has an old origin resembling the cancer evolution but TM may interfere with NLS driven signaling for natural selection of survival to evade NLS induced aggressive cancers. Our data suggest NLS is a dynamic inducer of EGFR oncogenesis during evolution for advanced cancers. Our model provides novel insights into the evolutionary role of NLS of oncogenic kinases in cancers.

Parental High-Fat Diet Promotes Inflammatory and Senescence-Related Changes in Prostate

Background. Obesity and dietary habits are associated with increased incidences of aging-related prostatic diseases. The present study was aimed to investigate transgenerational effects of chronic high-fat diet (HFD) feeding on inflammation and senescence-related changes in prostate. Methods. Sprague-Dawley rats were kept on either normal or HFD one. Senescence-associated β-galactosidase (SA β-gal) activity, inflammation, and cellular proliferation were determined in the prostate. Results. Increased SA β-gal activity, expression of p53, and cell proliferation marker PCNA were observed in ventral prostate of HFD-fed rats. Immunostaining for p53 and PCNA revealed that the p53 immunopositive cells were primarily in stroma while PCNA immunopositive cells were epithelial cells. An increase in expression of cycloxygenase-2 (COX-2) and phosphorylation of nuclear factor-kappa B (NF-kB) was observed in prostate of weaning pups HFD-fed parents. However, in adult pups, irrespective of dietary habit, a significant increase in the expression of COX-2, PCNA, phosphorylation of NF-kB, infiltration of inflammatory cells, and SA β-gal activity was observed. Conclusions. Present investigation reports that HFD feeding promotes accumulation of p53 expressing cells, proliferation of epithelial cells, and senescence-related changes in prostate. Further, parental HFD-feeding upholds inflammatory, proliferative, and senescence-related changes in prostate of pups.

Comprehensive assessment of estrogen receptor beta antibodies in cancer cell line models and tissue reveals critical limitations in reagent specificity

Estrogen Receptor-β (ERβ) has been implicated in many cancers. In prostate and breast cancer its function is controversial, but genetic studies implicate a role in cancer progression. Much of the confusion around ERβ stems from antibodies that are inadequately validated, yet have become standard tools for deciphering its role. Using an ERβ-inducible cell system we assessed commonly utilized ERβ antibodies and show that one of the most commonly used antibodies, NCL-ER-BETA, is non-specific for ERβ. Other antibodies have limited ERβ specificity or are only specific in one experimental modality. ERβ is commonly studied in MCF-7 (breast) and LNCaP (prostate) cancer cell lines, but we found no ERβ expression in either, using validated antibodies and independent mass spectrometry-based approaches. Our findings question conclusions made about ERβ using the NCL-ER-BETA antibody, or LNCaP and MCF-7 cell lines. We describe robust reagents, which detect ERβ across multiple experimental approaches and in clinical samples.

Human risk of diseases associated with red meat intake: Analysis of current theories and proposed role for metabolic incorporation of a non-human sialic acid

One of the most consistent epidemiological associations between diet and human disease risk is the impact of red meat consumption (beef, pork, and lamb, particularly in processed forms). While risk estimates vary, associations are reported with all-cause mortality, colorectal and other carcinomas, atherosclerotic cardiovascular disease, type II diabetes, and possibly other inflammatory processes. There are many proposed explanations for these associations, some long discussed in the literature. Attempts to explain the effects of red meat consumption have invoked various red meat-associated agents, including saturated fat, high salt intake, Trimethylamine-N-oxide (TMAO) generation by microbiota, and environmental pollutants contaminating red meat, none of which are specific for red meat. Even the frequently mentioned polycyclic aromatic carcinogens arising from high temperature cooking methods are not red meat specific, as these are also generated by grilling poultry or fish, as well as by other forms of cooking. The traditional explanations that appear to be more red meat specific invoke the impact of N-nitroso compounds, heme iron, and the potential of heme to catalyze endogenous nitrosation. However, heme can be denatured by cooking, high levels of plasma hemopexin will block its tissue delivery, and much higher amounts of heme likely originate from red blood cell breakdown in vivo. Therefore, red meat-derived heme could only contribute to colorectal carcinoma risk, via direct local effects. Also, none of these mechanisms explain the apparent human propensity i.e., other carnivores have not been reported at high risk for all these diseases. A more recently proposed hypothesis involves infectious agents in beef from specific dairy cattle as agents of colorectal cancer. We have also described another mechanistic explanation for the human propensity for risk of red-meat associated diseases that is consistent with most observations: metabolic incorporation of a non-human sialic acid N-glycolylneuraminic acid (Neu5Gc) into the tissues of red meat consumers and the subsequent interaction with inflammation-provoking antibodies against this "xenoautoantigen". Overall, we conclude that while multiple mechanisms are likely operative, many proposed theories to date are not specific for red meat, and that the viral and xenoautoantigen theories deserve further consideration. Importantly, there are potential non-toxic dietary antidotes, if the xenoautoantigen theory is indeed correct.

Prostate cancer in East Asia: evolving trend over the last decade

Prostate cancer is now becoming an emerging health priority in East Asia. Most of our current knowledge on Prostate cancer has been generated from studies conducted in Western population; however, there is considerable heterogeneity of Prostate cancer between East and West. In this article, we reviewed epidemiologic trends, risk factors, disease characteristics and management of Prostate cancer in East Asian population over the last decade. Growing evidence from East Asia suggests an important role of genetic and environmental risk factors interactions in the carcinogenesis of Prostate cancer. Exposure to westernized diet and life style and improvement in health care in combination contribute substantially to the increasing epidemic in this region. Diagnostic and treatment guidelines in East Asia are largely based on Western knowledge. Although there is a remarkable improvement in the outcome over the last decade, ample evidence suggests an inneglectable difference in diagnostic accuracy, treatment efficacy and adverse events between different populations. The knowledge from western countries should be calibrated in the Asian setting to provide a better race-based treatment approach. In this review, we intend to reveal the evolving trend of Prostate cancer in the last decade, in order to gain evidence to improve Prostate cancer prevention and control in East Asia.

[Rehabilitation of prostate cancer patients : A multidisciplinary consensus]

BACKGROUND

Even though several specialist groups, including the German Pension Insurance (Deutsche Rentenversicherung) and health insurance funds, participate in the rehabilitation of patients with prostate carcinoma, there is no standardized rehabilitation program available for these patients. Consequently, there is no transparency regarding the services provided within the scope of rehabilitation for the referring physicians to uro-oncological rehabilitation, in particular, neither for physicians at urological acute-care clinics, nor for the patients concerned. Rehabilitation clinics are rather left to their own devices as to which services they provide in the treatment of the respective disease and in social situations, but also with regard to the consulting services offered.

PROBLEM

Development of a standard for the rehabilitation of patients with prostate carcinoma, taking into account both specialist circles and self-help groups relevant to this matter.

METHODS

Specialist groups, including self-help groups participating in the rehabilitation of patients with prostate cancer, have formed an expert group and developed the present standard. To this end, a thematic unsystematic literature review was carried out in advance to provide an evidence-based foundation.

RESULTS

Views were given with regard to rehabilitation diagnostics, the therapy of urinary incontinence and erectile dysfunction, sport and physical exercise therapy, psycho-oncology, and social- and disease-related consulting. In this context, the focus was set on classification as well as on the consensus strength of the respective recommendations.

CONCLUSION

All parties involved in the rehabilitation of prostate cancer patients, as well as the patients and the responsible cost bearers, can now use the standard as an orientation guide.

Anti-androgenic effects of flavonols in prostate cancer

Dietary-derived agents, such as the flavonoids, are of particular interest for prostate cancer (PCa) chemoprevention as they may offer a favourable safety and side-effect profile. An agent that demonstrates action on the androgen receptor (AR) axis may have value for preventing or treating castrate-resistant PCa. Four main flavonols - quercetin, myricetin, kaempferol, and fisetin - have been demonstrated in laboratory studies to have chemopreventive action in both castrate-resistant and castrate-sensitive PCa models. Mechanisms of flavonol action on the AR axis in PCa have been proposed to be inhibition of the 5α-reductase enzymes, direct androgen competition, suppression of the AR complex and transactivation by coregulators such as c-Jun, Sp1, and the PI3K/Akt pathway. It is, however, still unclear with current levels of evidence whether AR axis-mediated effects can fully account for the flavonols' chemopreventive action.

Perceived influences on post-diagnostic dietary change among a group of men with prostate cancer

A cancer diagnosis is often associated with loss of agency and control that can adversely affect well-being. Patients may try to regain control through dietary change aimed at preventing progression and/or recurrence. Evidence for the effectiveness of post-diagnostic dietary change in prostate cancer is not conclusive, which can cause uncertainty among patients and health professionals. This qualitative study explored how eight men in the U.K., who had been diagnosed with prostate cancer in the previous 5 years, accounted for any post-diagnostic changes they made to their diet. Data were generated through semi-structured telephone interviews and were subjected to thematic analysis. This yielded two themes concerning the perceived nature and importance of dietary change and the perceived determinants of dietary change. The latter focused on internal dimensions such as agency and external dimensions such as the perceived role of relationships with health professionals, the availability of credible dietary information and family influences. The study points to the importance of the family context in enabling the men to implement dietary change. It is suggested that, even if health professionals can only offer qualified, general advice about diet, this may provide men with a focus for action and a means of regaining control.

Nutrition, dietary interventions and prostate cancer: the latest evidence

Prostate cancer (PCa) remains a leading cause of mortality in US men and the prevalence continues to rise world-wide especially in countries where men consume a 'Western-style' diet. Epidemiologic, preclinical and clinical studies suggest a potential role for dietary intake on the incidence and progression of PCa. 'This minireview provides an overview of recent published literature with regard to nutrients, dietary factors, dietary patterns and PCa incidence and progression. Low carbohydrates intake, soy protein, omega-3 (w-3) fat, green teas, tomatoes and tomato products and zyflamend showed promise in reducing PCa risk or progression. A higher saturated fat intake and a higher β-carotene status may increase risk. A 'U' shape relationship may exist between folate, vitamin C, vitamin D and calcium with PCa risk. Despite the inconsistent and inconclusive findings, the potential for a role of dietary intake for the prevention and treatment of PCa is promising. The combination of all the beneficial factors for PCa risk reduction in a healthy dietary pattern may be the best dietary advice. This pattern includes rich fruits and vegetables, reduced refined carbohydrates, total and saturated fats, and reduced cooked meats. Further carefully designed prospective trials are warranted.

The role of dietary fat throughout the prostate cancer trajectory

Prostate cancer is the second most common cancer diagnosed world-wide; however, patients demonstrate exceptionally high survival rates. Many lifestyle factors, including obesity and diet, are considered risk factors for advanced prostate cancer. Dietary fat is a fundamental contributor to obesity and may be specifically important for prostate cancer patients. Prostate cancer treatment can result in changes in body composition, affecting quality of life for survivors by increasing the risk of co-morbidities, like cardiovascular disease and diabetes. We aim to examine dietary fat throughout the prostate cancer treatment trajectory, including risk, cancer development and survivorship. Focusing on one specific nutrient throughout the prostate cancer trajectory provides a unique perspective of dietary fat in prostate cancer and the mechanisms that may exacerbate prostate cancer risk, progression and recurrence. Through this approach, we noted that high intake of dietary fat, especially, high intake of animal and saturated fats, may be associated with increased prostate cancer risk. In contrast, a low-fat diet, specifically low in saturated fat, may be beneficial for prostate cancer survivors by reducing tumor angiogenesis and cancer recurrence. The insulin-like growth factor (IGF)/Akt signaling pathway appears to be the key pathway moderating dietary fat intake and prostate cancer development and progression.

Men's knowledge and attitudes towards dietary prevention of a prostate cancer diagnosis: a qualitative study

Background

Prostate cancer (PC) incidence and progression may be influenced by dietary factors, but little is known about the acceptability of dietary modification to men at increased risk of PC. Qualitative interviews with men participating in the ProDiet study were undertaken to explore the feasibility of implementing dietary interventions for the prevention of prostate cancer.

Methods

An interview study nested within the ProDiet randomised feasibility trial of dietary interventions to prevent a PC diagnosis. Men (n = 133) who previously participated in community based prostate specific antigen (PSA) testing without PC but who were at increased risk of the disease were randomly allocation to both lycopene (lycopene or placebo capsules or lycopene rich diet) and green tea (green tea or placebo capsules or green tea drink) for 6 months. Semi-structured interviews were conducted with participants shortly after randomisation, to investigate attitudes towards dietary modification for PC prevention and dietary information. Interviews were audio-recorded, transcribed and analysed to identify common themes.

Results

Interviews were conducted with 21 participants aged 52-72 years with PSA levels between 2.5 and 2.95 ng/ml, or a negative prostate biopsy result. Most men identified the major causes of cancer in general to include diet, environment, ageing and genetic factors. This contrasted sharply with men’s uncertainty about PC aetiology, and the function of the prostate. Men were confused by conflicting messages in the media about dietary practices to promote health overall, but were positive about the potential of lycopene and green tea in relation to PC prevention, valuing their natural components. Furthermore these men wanted tailored dietary advice for PC prevention from their clinicians, whom they considered a trusted source of information.

Conclusion

Men at elevated risk of PC reported uncertainty about PC aetiology and the role of diet in PC prevention, but enthusiasm for dietary modifications that were perceived as ‘simple’ and ‘natural’. The men looked to clinicians to provide consistent disease specific dietary advice. These factors should be taken into consideration by clinicians discussing elevated PSA results with patients and those planning to embark on future trials investigating dietary modification interventions for the prevention of a PC diagnosis.

Gender relations and couple negotiations of British men's food practice changes after prostate cancer

Nutrition plays an important role in the health of men diagnosed with prostate cancer and dietary interventions can therefore be a significant part of prostate cancer survivorship supportive care. Family food provision, however, involves complex social interactions, which shape how men engage with their diets and dietary interventions. The role that gender plays in shaping prostate cancer couples' food practices and men's diets after a prostate cancer diagnosis is thought to be important but is little understood. This study explored couples' accounts of nutrition information seeking and diet change to gain a better understanding of how gender relations shaped men's food practices after prostate cancer diagnosis. Qualitative health interviews with men and their partners were conducted and analysed using interpretive descriptive methods. Findings demonstrated how couples navigated food change journeys that involved seeking information, deciding what changes were warranted and implementing and regulating diet changes. Two overarching themes that illustrated couples' food negotiations were called 'Seeking information and deciding on food changes' and 'Monitoring food changes'. Additional sub-themes described who led food changes, women's filtering of information, and moderation or 'treats'. Throughout these food change journeys, interactions between men and women were at play, demonstrating how gender relations and dynamics acted to shape couples' food negotiations and men's food practices. Findings reveal that attention to gender relations and the men's family food dynamics should inform diet interventions for men with prostate cancer in order to improve uptake.

High animal fat intake enhances prostate cancer progression and reduces glutathione peroxidase 3 expression in early stages of TRAMP mice

BACKGROUND

Prostate cancer is the most frequently diagnosed cancer in Western men, and more men have been diagnosed at younger ages in recent years. A high-fat Western-style diet is a known risk factor for prostate cancer and increases oxidative stress.

METHODS

We evaluated the association between dietary animal fat and expression of antioxidant enzymes, particularly glutathione peroxidase 3 (GPx3), in the early stages of transgenic adenocarcinoma of the mouse prostate (TRAMP) mice. Six-week-old male nontransgenic and TRAMP mice were placed on high animal fat (45% Kcal fat) or control (10% Kcal fat) diets and sacrificed after 5 or 10 weeks.

RESULTS

The histopathological score increased with age and high-fat diet consumption. The histopathological scores in dorsal and lateral lobes increased in the 10-week high-fat diet group (6.2±0.2 and 6.2±0.4, respectively) versus the 10-week control diet group (5.3±0.3 and 5.2±0.2, respectively). GPx3 decreased both at the mRNA and protein levels in mouse prostate. GPx3 mRNA expression decreased (∼36.27% and ∼23.91%, respectively) in the anterior and dorsolateral prostate of TRAMP mice fed a high-fat diet compared to TRAMP mice fed a control diet. Cholesterol treatment increased PC-3 human prostate cancer cell proliferation, decreased GPx3 mRNA and protein levels, and increased H2 O2 levels in culture medium. Moreover, increasing GPx3 mRNA expression by troglitazone in PC-3 cells decreased cell proliferation and lowered H2 O2 levels.

CONCLUSIONS

Dietary fat enhances prostate cancer progression, possibly by suppressing GPx3 expression and increasing proliferation of prostate intraepithelial neoplasia (PIN) epithelial cells.

Estrogen receptor beta in prostate cancer: friend or foe?

Prostate cancer is the commonest, non-cutaneous cancer in men. At present, there is no cure for the advanced, castration-resistant form of the disease. Estrogen has been shown to be important in prostate carcinogenesis, with evidence resulting from epidemiological, cancer cell line, human tissue and animal studies. The prostate expresses both estrogen receptor alpha (ERA) and estrogen receptor beta (ERB). Most evidence suggests that ERA mediates the harmful effects of estrogen in the prostate, whereas ERB is tumour suppressive, but trials of ERB-selective agents have not translated into improved clinical outcomes. The role of ERB in the prostate remains unclear and there is increasing evidence that isoforms of ERB may be oncogenic. Detailed study of ERB and ERB isoforms in the prostate is required to establish their cell-specific roles, in order to determine if therapies can be directed towards ERB-dependent pathways. In this review, we summarise evidence on the role of ERB in prostate cancer and highlight areas for future research.

Dietary antioxidants and prostate cancer: a review

Prostate cancer is the most common noncutaneous cancer in men in the United States. Several studies have examined the relationship between prostate cancer and antioxidants; however, the results of these studies are inconsistent. This article provides a systematic review of studies on prostate cancer and antioxidant intake from diet and supplements. Tea and coffee appear to offer protection against advanced prostate cancer. Different forms of vitamin E appear to exert different effects on prostate cancer, with alpha-tocopherol potentially increasing and gamma-tocopherol potentially decreasing risk of the disease. There is no strong evidence for a beneficial effect of selenium, vitamin C, or beta-carotene, whereas lycopene appears to be negatively associated with risk of the disease. The effect of dietary antioxidants on prostate cancer remains undefined and inconclusive, with different antioxidants affecting prostate cancer risk differentially. Further studies are needed to clarify the relationship between antioxidants and prostate cancer risk and to delineate the underlying mechanisms.

Involvement of a non-human sialic Acid in human cancer

Sialic acids are common monosaccharides that are widely expressed as outer terminal units on all vertebrate cell surfaces, and play fundamental roles in cell–cell and cell–microenvironment interactions. The predominant sialic acids on most mammalian cells are N-glycolylneuraminic acid (Neu5Gc) and N-acetylneuraminic acid (Neu5Ac). Neu5Gc is notable for its deficiency in humans due to a species-specific and species-universal inactivating deletion in the CMAH gene encoding the hydroxylase that converts CMP-Neu5Ac to CMP-Neu5Gc. However, Neu5Gc is metabolically incorporated into human tissues from dietary sources (particularly red meat), and detected at even higher levels in some human cancers. Early life exposure to Neu5Gc-containing foods in the presence of certain commensal bacteria that incorporate dietary Neu5Gc into lipooligosaccharides can lead to generation of antibodies that are also cross-reactive against Neu5Gc-containing glycans in human tissues (“xeno-autoantigens”). Such anti-Neu5Gc “xeno-autoantibodies” are found in all humans, although ranging widely in levels among individuals, and displaying diverse and variable specificities for the underlying glycan. Experimental evidence in a human-like Neu5Gc-deficient Cmah^−/−mouse model shows that inflammation due to “xenosialitis” caused by this antigen–antibody interaction can promote tumor progression, suggesting a likely mechanism for the well-known epidemiological link between red meat consumption and carcinoma risk. In this review, we discuss the history of this field, mechanisms of Neu5Gc incorporation into tissues, the origin and specificities of human anti-Neu5Gc antibodies, their use as possible cancer biomarkers, implications of xenosialitis in cancer initiation and progression, and current and future approaches toward immunotherapy that could take advantage of this unusual human-specific phenomenon.

Diet and cancer: risk factors and epidemiological evidence

BACKGROUND

Diet represents 30-35% of risk factors that contribute to the onset of cancer. Some foods and dietary patterns have been linked to the risk of various cancers. However epidemiological available data are not consistent for many foods and the associations with cancer risk remain unclear. The concerns about this issue are considered like a "Hot topic" for oncologists and general population.

OBJECTIVE

The aim of this report is to present a review of the published epidemiologic research to date reflecting the most current scientific evidence related to diet and cancer risk.

DESIGN

EMBASE and PubMed-NCBI were searched for relevant articles up to October 2013 that identified potentials interactions between foods or dietary patterns with cancer risk.

RESULTS

There is no conclusive evidence as an independent risk factor for isolated nutrients versus adoption of dietary patterns for cancer risk. Moderate physical activity after breast cancer diagnosis contributes to 40% reduction of recurrence/disease-specific mortality. Cancer colon risk derived from meat intake is influenced by both total intake and its frequency. The interaction of phenolic compounds on metabolic and signaling pathways like P450, MAP kinase, PI3 kinase, IGF-1, NF-kB and ROS seems to exert an inhibitory effect on cell proliferation and tumor metastasis and induces apoptosis in various types of cancer cells, including colon, lung, prostate, hepatocellular or breast cancer.

CONCLUSIONS

There is a direct relationship between unhealthy diet and lifestyle with the increase of tumor development and cancer risk. For this reason, a good nutritional status based on a balanced diet constitutes one of the main preventive factors from tumors. However the mixed results from epidemiologic studies hinder to get unequivocal and consistent evidence about the interaction between diet and cancer risk. More epidemiological studies will be needed in the future to clarify this issue.

Dietary patterns and prostate cancer risk: report from the population based ULSAM cohort study of Swedish men

Dietary pattern analyses have increased the possibilities to detect associations between diet and disease. However, studies on dietary pattern and prostate cancer are scarce. Food intake data in the Uppsala Longitudinal Study of Adult Men cohort was determined by 7-day food records. Adherence to a modified Mediterranean Diet Score (mMDS) and a low carbohydrate-high protein (LCHP) score were grouped as low, medium, or high in the whole study population (n = 1,044) and in those identified as adequate reporters of energy intake (n = 566), respectively. Prostate cancer risk was analyzed with Cox proportional hazard regression (median follow-up 13 years) and competing risk of death was considered. There were no associations between dietary patterns and prostate cancer (n = 133) in the whole study population. Among adequate reporters the mMDS was not associated with prostate cancer (n = 72). The LCHP score was inversely related to prostate cancer in adequate reporters, adjusted hazard ratios; 0.55 (0.32-0.96) for medium and 0.47 (0.21-1.04) for high compared to low adherent participants (P-for-trend 0.04). Risk relations were not attributable to competing risk of death. In this study, a LCHP diet was associated with lower prostate cancer incidence. Relations emerged in adequate reporters, underscoring the importance of high-quality dietary data.

Omega-3 fatty acids inhibit tumor growth in a rat model of bladder cancer

Omega-3 (ω-3) fatty acids have been tested on prevention and treatment of several cancer types, but the efficacy on “in vivo” bladder cancer has not been analyzed yet. This study aimed at evaluating the chemopreventive efficacy of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) mixture in an animal model of bladder cancer. Forty-four male Wistar rats were divided into 4 groups during a 20-week protocol: control; carcinogen—N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN); ω-3 (DHA + EPA); and ω-3 + BBN. BBN and ω-3 were given during the initial 8 weeks. At week 20 blood and bladder were collected and checked for the presence of urothelium lesions and tumors, markers of inflammation, proliferation, and redox status. Incidence of bladder carcinoma was, control (0%), ω-3 (0%), BBN (65%), and ω-3 + BBN (62.5%). The ω-3 + BBN group had no infiltrative tumors or carcinoma in situ, and tumor volume was significantly reduced compared to the BBN (0.9 ± 0.1 mm³ versus 112.5 ± 6.4 mm³). Also, it showed a reduced MDA/TAS ratio and BBN-induced serum CRP, TGF-β1, and CD31 were prevented. In conclusion, omega-3 fatty acids inhibit the development of premalignant and malignant lesions in a rat model of bladder cancer, which might be due to anti-inflammatory, antioxidant, anti-proliferative, and anti-angiogenic properties.

Consumption of deep-fried foods and risk of prostate cancer

BACKGROUND

Evidence suggests that high-heat cooking methods may increase the risk of prostate cancer (PCa). The addition of oil/fat, as in deep-frying, may be of particular concern, and has not specifically been investigated in relation to PCa. Potential mechanisms include the formation of potentially carcinogenic agents such as aldehydes, acrolein, heterocyclic amines, polycyclic aromatic hydrocarbons, and acrylamide.

METHODS

We estimated odds ratios (OR) and 95% confidence intervals (CI) for the association between tertiles of intake of deep-fried foods from a food frequency questionnaire (French fries, fried chicken, fried fish, doughnuts and snack chips) and PCa risk, adjusted for potential confounders, among 1,549 cases and 1,492 controls. We additionally examined associations with more aggressive PCa (defined as regional/distant stage, elevated Gleason score or prostate-specific antigen level).

RESULTS

Compared with <1/week, there was a positive association with PCa risk for intake ≥1/week of French fries (OR = 1.37; 95% CI, 1.11-1.69), fried chicken (OR = 1.30; 95% CI, 1.04-1.62), fried fish (OR = 1.32; 95% CI, 1.05-1.66), and doughnuts (OR = 1.35; 95% CI, 1.11-1.66). There was no association for snack chips (OR = 1.08; 95% CI, 0.89-1.32). Most of the estimates were slightly stronger for more aggressive disease (OR = 1.41; 95% CI, 1.04-1.92 for fried fish).

CONCLUSION

Regular consumption of select deep-fried foods is associated with increased PCa risk. Whether this risk is specific to deep-fried foods, or whether it represents risk associated with regular intake of foods exposed to high heat and/or other aspects of the Western lifestyle, such as fast food consumption, remains to be determined.

Mediterranean Diet Score and prostate cancer risk in a Swedish population-based case-control study

Several individual components of the Mediterranean diet have been shown to offer protection against prostate cancer. The present study is the first to investigate the association between adherence to the Mediterranean diet and the relative risk of prostate cancer. We also explored the usefulness of the Mediterranean Diet Score (MDS) in a non-Mediterranean population. FFQ data were obtained from 1482 incident prostate cancer patients and 1108 population-based controls in the Cancer of the Prostate in Sweden (CAPS) study. We defined five MDS variants with different components or using either study-specific intakes or intakes in a Greek reference population as cut-off values between low and high intake of each component. Unconditional logistic regression was used to estimate the relative risk of prostate cancer for high and medium v. low MDS, as well as potential associations with the individual score components. No statistically significant association was found between adherence to the Mediterranean diet based on any of the MDS variants and prostate cancer risk (OR range: 0·96-1·19 for total prostate cancer, comparing high with low adherence). Overall, we found little support for an association between the Mediterranean diet and prostate cancer in this Northern European study population. Despite potential limitations inherent in the study or in the build-up of a dietary score, we suggest that the original MDS with study-specific median intakes as cut-off values between low and high intake is useful in assessing the adherence to the Mediterranean diet in non-Mediterranean populations.

Risk of localized and advanced prostate cancer among immigrants versus native-born Swedish men: a nation-wide population-based study

PURPOSE

Prostate cancer (PCa) incidence and prognosis vary geographically. We examined possible differences in PCa risk by clinical risk category between native-born and immigrant populations in Sweden. Our hypothesis was that lower PSA-testing uptake among foreign-born men would result in lower rates of localized disease, and similar or higher risk of metastatic disease.

METHODS

Using the Prostate Cancer database Sweden, we identified 117,328 men with PCa diagnosed from 1991 to 2008, of which 8,332 were foreign born. For each case, 5 cancer-free matched controls were randomly selected from the population register. Conditional logistic regression was used to compare low risk, intermediate risk, high risk, regionally metastatic, and distant metastatic PCa based upon region of origin.

RESULTS

Across all risk categories, immigrants had significantly lower PCa risk than native-born Swedish men, except North Americans and Northern Europeans. The lowest PCa risk was observed in men from the Middle East, Southern Europe, and Asia. Multivariable adjustment for socioeconomic factors and comorbidities did not materially change risk estimates. Older age at immigration and more recent arrival in Sweden were associated with lower PCa risk. Non-native men were less likely to be diagnosed with PCa through PSA testing during a health checkup.

CONCLUSIONS

The risk for all stages of PCa was lower among first-generation immigrants to Sweden compared with native-born men. Older age at immigration and more recent immigration were associated with particularly low risks. Patterns of PSA testing appeared to only partly explain the differences in PCa risk, since immigrant men also had a lower risk of metastatic disease.

Dietary intakes of carbohydrates in relation to prostate cancer risk: a prospective study in the Malmö Diet and Cancer cohort

BACKGROUND

Dietary carbohydrates have been implicated in relation to prostate cancer.

OBJECTIVE

Our objective was to examine the associations between dietary intakes of carbohydrates, fiber, and their food sources and risk of prostate cancer, overall and by case severity, in the Malmö Diet and Cancer cohort.

DESIGN

The analysis included 8128 men aged 45-73 y without a history of cancer, cardiovascular disease, or diabetes and who were classified as adequate energy reporters. After a median follow-up time of 15 y, prostate cancer was diagnosed in 817 men. We used Cox proportional hazards regression to model associations between energy-adjusted nutrient and food intakes with risk of incident prostate cancer, with competing risk of death from non-prostate cancer causes taken into account.

RESULTS

After adjustment for age and other known or potential risk factors, we observed no associations between total carbohydrates or dietary fiber and prostate cancer. We observed positive associations between the intake of low-fiber cereals with overall and low-risk prostate cancer and between intakes of cake and biscuits and rice and pasta with low-risk prostate cancer (all P-trend < 0.05). A high intake compared with zero consumption of sugar-sweetened beverages was associated with increased risk of symptomatic prostate cancer (HR: 1.38; 95% CI: 1.04, 1.84).

CONCLUSIONS

Results from this large study with high-validity dietary data suggest that a high intake of refined carbohydrates may be associated with increased risk of prostate cancer. However we observed no significant associations with high-risk prostate cancer, and not all foods that are typically high in refined carbohydrates were associated with prostate cancer.

The relationship between nutrition and prostate cancer: is more always better?

CONTEXT

Prostate cancer (PCa) remains one of the most diagnosed malignancies in the world, correlating with regions where men consume more of a so-called Western-style diet. As such, there is much interest in understanding the role of lifestyle and diet on the incidence and progression of PCa.

OBJECTIVE

To provide a summary of published literature with regard to dietary macro- and micronutrients and PCa incidence and progression.

EVIDENCE ACQUISITION

A literature search was completed using the PubMed database for all studies published on diet and PCa in June 2012 or earlier. Primary literature and meta-analyses were given preference over other review articles when possible.

EVIDENCE SYNTHESIS

The literature was reviewed on seven dietary components: carbohydrates, protein, fat and cholesterol, vegetables, vitamins and minerals, and phytochemicals. Current literature linking these nutrients to PCa is limited at best, but trends in the published data suggest consumption of carbohydrates, saturated and ω-6 fats, and certain vitamin supplements may promote PCa risk and progression. Conversely, consumption of many plant phytochemicals and ω-3 fatty acids seem to slow the risk and progression of the disease. All other nutrients seem to have no effect or data are inconclusive. A brief summary about the clinical implications of dietary interventions with respect to PCa prevention, treatment, and survivorship is provided.

CONCLUSIONS

Due to the number and heterogeneity of published studies investigating diet and PCa, it is difficult to determine what nutrients make up the perfect diet for the primary and secondary prevention of PCa. Because diets are made of multiple macro- and micronutrients, further prospective studies are warranted, particularly those investigating the relationship between whole foods instead of a single nutritional component.

Anti-proliferative effects of physiological concentrations of enterolactone in models of prostate tumourigenesis

SCOPE

There is evidence that a mammalian lignan, enterolactone (ENL), decreases the proliferation rate of prostate cancer cells, although previous studies have used concentrations difficult to achieve through dietary modification. We have therefore investigated the anti-proliferative effects of ENL in an in vitro model of prostate tumourigenesis at concentrations reported to occur in a range of male populations.

METHODS AND RESULTS

The effects of 0.1 and 1 μM ENL on three markers of viability and proliferation (metabolic activity, growth kinetics, and cell cycle progression) were assessed in the RWPE-1, WPE1-NA22, WPE1-NB14, WPE1-NB11, WPE1-NB26, LNCaP, and PC-3 cell lines over 72 h. Based on these data, we quantified the expression levels of 12 genes involved in the control of DNA replication initiation using TaqMan real-time PCR in the WPE1-NA22, WPE1-NB14, WPE1-NB11, and WPE1-NB26 cell lines. ENL significantly inhibited the abnormal proliferation of the WPE1-NB14 and WPE1-NB11 cell lines and appears to be a consequence of decreased expression of abnormal chromatin licensing and DNA replication factor 1.

CONCLUSION

In contrast to previous studies, concentrations of ENL that are reported after dietary intervention restrict the proliferation of early-stage tumourigenic prostate cell lines by inhibiting the abnormal formation of complexes that initiate DNA replication.

Nutritional genomics for the characterization of the effect of bioactive molecules in lipid metabolism and related pathways

Cardiovascular disease and cancer are the main causes of morbidity and mortality worldwide. Thus, investigators have focused their efforts on gaining insight into understanding the mechanisms involved in the development and evolution of these diseases. In the past decade, and with the contribution of the -omics technologies, strong evidence has supported an essential role of gene-nutrient interactions in these processes, pointing at natural bioactive molecules as promising complementary agents that are useful in preventing or mitigating these diseases. In addition, alterations in lipid metabolism have recently gained strong interest since they have been described as a common event required for the progression of both diseases. In the present review, we give an overview of lipid metabolism, mainly focusing on lipoprotein metabolism and the mechanisms controlling lipid homeostasis. In addition, we review the modulation of lipid metabolism by bioactive molecules, highlighting their potential use as therapeutic agents in preventing, and treating chronic diseases such as cardiovascular disease and cancer. Finally, we report the usefulness of the -omics technologies in nutritional research, focusing on recent findings, within nutritional genomics, in the interaction of bioactive components from foods with several genes that are involved in the development and progression of these diseases.

Lifestyle factors in cancer survivorship

Lifestyle factors have been linked to the risk of developing many common malignancies and, increasingly, to prognosis. Observational evidence has shown a relationship between so-called energy balance factors (ie, diet, physical activity, and body weight) and risk of cancer recurrence and mortality in cancers of the breast, prostate, colon and, perhaps, other cancers. Interventional work has shown that individuals who make favorable changes in these lifestyle factors after cancer diagnosis feel better, experience less fatigue, and may possibly even decrease risk of cancer recurrence. Other lifestyle behaviors, such as smoking and alcohol consumption, have also been linked to the development of common cancers and may have important health consequences for cancer survivors. This article reviews the evidence that links lifestyle factors to cancer outcomes, provides clinical recommendations for cancer survivors, and describes future directions for lifestyle research in cancer survivors.