Elizabeth Grainger

A Combination of Tomato and Soy Products for Men With Recurring Prostate Cancer and Rising Prostate Specific Antigen

Tomato and soy products are hypothesized to reduce the risk of prostate cancer or enhance efficacy of therapy. A study was completed to determine if men with active prostate cancer will adhere to a dietary intervention rich in tomato products and a soy protein supplement men (n = 41) with recurrent, asymptomatic prostate cancer were randomized among 2 groups: Group A (n = 20) consumed tomato products (no soy) for Weeks 0 through 4, targeting a minimum of 25 mg of lycopene/day. Group B (n = 21) consumed soy (no tomatoes) for Weeks 0 through 4, providing 40 g of soy protein/day. For Weeks 4 through 8, all men consumed a combined tomato-rich diet and soy supplements. No grade II through IV toxicities were observed. During Weeks 0 through 4, mean daily lycopene intake for Group A was 43 mg (± 15 mg) and mean soy intake for Group B was 39 g (± 1 g), remaining similar during Weeks 4 through 8. Serum lycopene increased from 0.72 ± 0.09 μ mol/l to 1.21 ± 0.10 μ mol/l (P < 0.0001) and urinary isoflavone excretion increased from not detectable to 54.1 ± 5.7 μ mol/l (P < 0.05) with 8 wk of diet intervention. Serum prostate-specific antigen decreased between Weeks 0 and 8 for 14 / 41 men (34%). Mean serum vascular endothelial growth factor for the entire group was reduced from 87 to 51 ng/ml (P < 0.05) over 8 wk. In conclusion, prostate cancer patients will consume diets rich in tomato products and soy with excellent compliance and bioavailability of phytochemicals. Further studies combining tomato and soy foods to determine efficacy for prostate cancer prevention or management are encouraged.

Tomato-based food products for prostate cancer prevention: what have we learned?

Evidence derived from a vast array of laboratory studies and epidemiological investigations have implicated diets rich in fruits and vegetables with a reduced risk of certain cancers. However, these approaches cannot demonstrate causal relationships and there is a paucity of randomized, controlled trials due to the difficulties involved with executing studies of food and behavioral change. Rather than pursuing the definitive intervention trials that are necessary, the thrust of research in recent decades has been driven by a reductionist approach focusing upon the identification of bioactive components in fruits and vegetables with the subsequent development of single agents using a pharmacologic approach. At this point in time, there are no chemopreventive strategies that are standard of care in medical practice that have resulted from this approach. This review describes an alternative approach focusing upon development of tomato-based food products for human clinical trials targeting cancer prevention and as an adjunct to therapy. Tomatoes are a source of bioactive phytochemicals and are widely consumed. The phytochemical pattern of tomato products can be manipulated to optimize anticancer activity through genetics, horticultural techniques, and food processing. The opportunity to develop a highly consistent tomato-based food product rich in anticancer phytochemicals for clinical trials targeting specific cancers, particularly the prostate, necessitates the interactive transdisciplinary research efforts of horticulturalists, food technologists, cancer biologists, and clinical translational investigators.

Consumption of dietary supplements and over-the-counter and prescription medications in men participating in the Prostate Cancer Prevention Trial at an academic center

OBJECTIVE It is hypothesized that dietary patterns, individual nutrients, and specific prescription and over-the-counter medications may influence prostate carcinogenesis. Little information is available regarding the use of these products among men who are participating in prevention trials targeting prostate cancer. MATERIALS AND METHODS A total of 92 men (mean age 69 years) participating in the Prostate Cancer Prevention Trial (PCPT) at an academic center were asked to bring all nutritional supplements and medications to regularly scheduled study visits. RESULTS Data were collected on 86 of 92 men. We found that 85% of men in the PCPT regularly consumed at least 1 nutritional supplement. The mean (+/-standard deviation) number of dietary supplements consumed per man was 3.3 +/- 3.5 (range 0-21). A multivitamin and multimineral (73%) supplement was the most common product consumed. Single-nutrient supplements regularly consumed included: vitamin E (48%), vitamin C (31%), calcium (24%), and selenium (7%). Of men, 36% reported consumption of herbal products. Medications frequently consumed during the study period that may influence prostate carcinogenesis included nonsteroidal antiinflammatory drugs (57%), antihypertensives (49%), lipid lowering agents (27%), and aspirin (64%). CONCLUSIONS Participants in the PCPT at an academic center have a high propensity for dietary supplement use. Many, such as vitamin E and selenium, are hypothesized to influence the risk of prostate cancer. Several of the medications commonly consumed, including aspirin, nonsteroidal antiinflammatory drugs, and statins, are being investigated as chemopreventive agents. Investigators designing prostate cancer chemoprevention trials should consider including detailed documentation of exposure to these products that may influence study outcomes.

Compartmental and noncompartmental modeling of 13C-lycopene absorption, isomerization, and distribution kinetics in healthy adults

BACKGROUND Lycopene, which is a red carotenoid in tomatoes, has been hypothesized to mediate disease-preventive effects associated with tomato consumption. Lycopene is consumed primarily as the all-trans geometric isomer in foods, whereas human plasma and tissues show greater proportions of cis isomers. OBJECTIVE With the use of compartmental modeling and stable isotope technology, we determined whether endogenous all-trans-to-cis-lycopene isomerization or isomeric-bioavailability differences underlie the greater proportion of lycopene cis isomers in human tissues than in tomato foods. DESIGN Healthy men (n = 4) and women (n = 4) consumed (13)C-lycopene (10.2 mg; 82% all-trans and 18% cis), and plasma was collected over 28 d. Unlabeled and (13)C-labeled total lycopene and lycopene-isomer plasma concentrations, which were measured with the use of high-performance liquid chromatography-mass spectrometry, were fit to a 7-compartment model. RESULTS Subjects absorbed a mean ± SEM of 23% ± 6% of the lycopene. The proportion of plasma cis-(13)C-lycopene isomers increased over time, and all-trans had a shorter half-life than that of cis isomers (5.3 ± 0.3 and 8.8 ± 0.6 d, respectively; P < 0.001) and an earlier time to reach maximal plasma concentration than that of cis isomers (28 ± 7 and 48 ± 9 h, respectively). A compartmental model that allowed for interindividual differences in cis- and all-trans-lycopene bioavailability and endogenous trans-to-cis-lycopene isomerization was predictive of plasma (13)C and unlabeled cis- and all-trans-lycopene concentrations. Although the bioavailability of cis (24.5% ± 6%) and all-trans (23.2% ± 8%) isomers did not differ, endogenous isomerization (0.97 ± 0.25 μmol/d in the fast-turnover tissue lycopene pool) drove tissue and plasma isomeric profiles. CONCLUSION (13)C-Lycopene combined with physiologic compartmental modeling provides a strategy for following complex in vivo metabolic processes in humans and reveals that postabsorptive trans-to-cis-lycopene isomerization, and not the differential bioavailability of isomers, drives tissue and plasma enrichment of cis-lycopene. This trial was registered at clinicaltrials.gov as NCT01692340.

Consumption of Soy Isoflavone Enriched Bread in Men with Prostate Cancer Is Associated with Reduced Proinflammatory Cytokines and Immunosuppressive Cells

We hypothesized that soy phytochemicals may have immunomodulatory properties that may affect prostate carcinogenesis and progression. A randomized, phase II trial was conducted in 32 patients with prostate cancer with asymptomatic biochemical recurrence but no measurable disease on standard staging studies. Patients were randomized to two slices of soy bread (34 mg isoflavones/slice) or soy bread containing almond powder daily as a source of β-glucosidase. Flow cytometry and bioplex assays were used to measure cytokines or immune cell phenotype in blood at baseline (day 0) and following intervention (day 56). Adequate blood samples were available at enrollment and day 56 and evaluated. Multiple plasma cytokines and chemokines were significantly decreased on day 56 versus baseline. Subgroup analysis indicated reduced TH1 (P = 0.028) and myeloid-derived suppressor cell (MDSC)-associated cytokines (P = 0.035). TH2 and TH17 cytokines were not significantly altered. Phenotypic analysis revealed no change in CD8+ or CD4+ T cells but showed increased CD56+ natural killer (NK) cells (P = 0.038). The percentage of cells with a T regulatory cell phenotype (CD4+CD25+FoxP3+) was significantly decreased after 56 days of soy bread (P = 0.0136). Significantly decreased monocytic (CD33+HLADRnegCD14+) MDSC were observed in patients consuming soy bread (P = 0.0056). These data suggest that soy bread modulates systemic soluble and cellular biomarkers consistent with limiting inflammation and suppression of MDSCs. Additional studies to elucidate impact on the carcinogenic process or as a complement to immune-based therapy are required. Cancer Prev Res; 8(11); 1036–44. ©2015 AACR.

The Individualized Diet and Exercise Adherence Pilot Trial (IDEA-P) in prostate cancer patients undergoing androgen deprivation therapy: study protocol for a randomized controlled trial

BackgroundAndrogen deprivation therapy (ADT) is the foundation of treatment for men with metastatic prostate cancer and is now frequently incorporated into multimodality strategies for the curative treatment of locally advanced prostate cancer. Nevertheless, the catabolic effects of ADT result in meaningful adverse effects on physiological and quality of life outcomes, which may, in turn, increase the risk of functional decline, frailty, cardiovascular disease, and metabolic syndrome. Recent evidence demonstrates that lifestyle intervention promoting change in exercise and dietary behaviors is a promising approach, and may offset, or even reverse, the adverse effects accompanying ADT. Unfortunately, the limited existing studies of the effects of exercise and dietary interventions targeting patients with prostate cancer on ADT are characterized by high attrition rates and poor postintervention maintenance of treatment effects. Consequently, the Individualized Diet and Exercise Adherence Pilot Trial (IDEA-P) is designed to contrast the effects of a lifestyle intervention designed to promote independent self-management of exercise and dietary behavior with those of standard care disease management approach in the treatment of prostate cancer.Methods/DesignA total of 40 patients with prostate cancer undergoing ADT will be randomly assigned to lifestyle intervention or standard care. Outcomes of interest in IDEA-P include changes in self-reported and objectively assessed physical function and physical activity, dietary behavior, body composition, muscular strength, and quality of life. Outcomes will be obtained at baseline, 2-month, and 3-month assessments by trial personnel blinded to participants’ randomization assignment.DiscussionFindings from this study will establish the feasibility and preliminary efficacy of an innovative lifestyle intervention designed to promote progressively independent self-regulated exercise and dietary behavior change in the treatment of patients with prostate cancer undergoing ADT.Trial registrationClinicalTrials.gov NCT02050906.

Dietary Intake, Food Processing, and Cooking Methods Among Amish and Non-Amish Adults Living in Ohio Appalachia: Relevance to Nutritional Risk Factors for Cancer

This studys purpose was to examine the source, storage, preparation, and intake of food among Amish and non-Amish adults to understand dietary practices as a potential contributing factor to lower cancer incidence rates. Interviews were conducted with a random sample of 134 Amish and 154 non-Amish adults including questions about dietary practices and a 24-h dietary recall. Amish compared to non-Amish adults reported (1) less refrigeration in homes (85% vs. 100%, P < .01); (2) rarely/never obtaining food from restaurants and grocery stores (P < .01); (3) consuming less alcohol (P < .01); (4) consuming fewer daily servings of vegetables (males: 1.2 vs. 1.9 servings/day, P < .01; females: 1.0 vs. 2.1 servings/day, P < .01); and (5) a greater percentage of energy from saturated fat (males: 16.7% vs. 12.6%, P < .01; females: 16.3% vs. 12.0%, P < .01). Amish males reported greater amount of energy intake (2780 kcal vs. 2298 kcal, P = .03) compared to non-Amish males. Amish and non-Amish dietary patterns show some differences that may impact cancer although neither group achieves current diet and cancer prevention guidelines. Lifestyle factors, screening, and healthcare access may be contributing to the lower cancer incidence rates among the Amish and these results suggest areas of intervention to reduce the cancer burden.

Absorption and Distribution Kinetics of the 13C-Labeled Tomato Carotenoid Phytoene in Healthy Adults

BACKGROUND Phytoene is a tomato carotenoid that may contribute to the apparent health benefits of tomato consumption. Although phytoene is a less prominent tomato carotenoid than lycopene, it is a major carotenoid in various human tissues. Phytoene distribution to plasma lipoproteins and tissues differs from lycopene, suggesting the kinetics of phytoene and lycopene differ. OBJECTIVE The objective of this study was to characterize the kinetic parameters of phytoene absorption, distribution, and excretion in adults, to better understand why biodistribution of phytoene differs from lycopene. METHODS Four adults (2 males, 2 females) maintained a controlled phytoene diet (1-5 mg/d) for 42 d. On day 14, each consumed 3.2 mg (13)C-phytoene, produced using tomato cell suspension culture technology. Blood samples were collected at 0, 1-15, 17, 21, and 24 h and 2, 3, 4, 7, 10, 14, 17, 21, and 28 d after (13)C-phytoene consumption. Plasma-unlabeled and plasma-labeled phytoene concentrations were determined using ultra-HPLC-quadrupole time-of-flight-mass spectrometry, and data were fit to a 7-compartment carotenoid kinetic model using WinSAAM 3.0.7 software. RESULTS Subjects were compliant with a controlled phytoene diet, consuming a mean ± SE of 2.5 ± 0.6 mg/d, resulting in a plasma unlabeled phytoene concentration of 71 ± 14 nmol/L. A maximal plasma (13)C-phytoene concentration of 55.6 ± 5.9 nM was achieved 19.8 ± 9.2 h after consumption, and the plasma half-life was 2.3 ± 0.2 d. Compared with previous results for lycopene, phytoene bioavailability was nearly double at 58% ± 19%, the clearance rate from chylomicrons was slower, and the rates of deposition into and utilization by the slow turnover tissue compartment were nearly 3 times greater. CONCLUSIONS Although only differing from lycopene by 4 double bonds, phytoene exhibits markedly different kinetic characteristics in human plasma, providing insight into metabolic processes contributing to phytoene enrichment in plasma and tissues compared with lycopene. This trial was registered at clinicaltrials.gov as NCT01692340.

Isoflavone pharmacokinetics and metabolism after consumption of a standardized soy and soy-almond bread in men with asymptomatic prostate cancer

Epidemiologic associations suggest that populations consuming substantial amounts of dietary soy exhibit a lower risk of prostate cancer. A 20-week randomized, phase II, crossover trial was conducted in 32 men with asymptomatic prostate cancer. The crossover involved 8 weeks each of soy bread (SB) and soy–almond bread (SAB). The primary objective was to investigate isoflavone bioavailability and metabolite profile. Secondary objectives include safety, compliance, and assessment of biomarkers linked to prostate carcinogenesis. Two distinct SBs were formulated to deliver approximately 60 mg aglycone equivalents of isoflavones per day. The isoflavones were present as aglycones (∼78% as aglycones) in the SAB whereas in the standard SB predominantly as glucosides (18% total isoflavones as aglycones). Compliance to SB (97% ± 4%) and SAB (92% ± 18%) was excellent; toxicity was rare and limited to grade 1 gastrointestinal complaints. Pharmacokinetic studies between SB and SAB showed modest differences. Peak serum concentration time (Tmax) was significantly faster with SAB meal compared with SB in some isoflavonoids, and AUC0 to 24 h of dihydrodaidzein and O-desmethylangolensin was significantly greater after an SB meal. An exploratory cluster analysis was used to identify four isoflavone-metabolizing phenotypes. Insulin-like growth factor–binding protein increased significantly by 41% (P = 0.024) with soy intervention. Findings from this study provide the necessary framework to study isoflavone-metabolizing phenotypes as a strategy for identification of individuals that might benefit or show resistance to cancer preventive strategies using dietary soy. A standardized SB used for future large-scale randomized clinical trials to affect human prostate carcinogenesis is feasible. Cancer Prev Res; 8(11); 1045–54. ©2015 AACR.

A comparison of plasma and prostate lycopene in response to typical servings of tomato soup, sauce or juice in men before prostatectomy

Tomato product consumption and estimated lycopene intake are hypothesised to reduce the risk of prostate cancer. To define the impact of typical servings of commercially available tomato products on resultant plasma and prostate lycopene concentrations, men scheduled to undergo prostatectomy (n 33) were randomised either to a lycopene-restricted control group ( < 5 mg lycopene/d) or to a tomato soup (2-2¾ cups prepared/d), tomato sauce (142-198 g/d or 5-7 ounces/d) or vegetable juice (325-488 ml/d or 11-16·5 fluid ounces/d) intervention providing 25-35 mg lycopene/d. Plasma and prostate carotenoid concentrations were measured by HPLC. Tomato soup, sauce and juice consumption significantly increased plasma lycopene concentration from 0·68 (sem 0·1) to 1·13 (sem 0·09) μmol/l (66 %), 0·48 (sem 0·09) to 0·82 (sem 0·12) μmol/l (71 %) and 0·49 (sem 0·12) to 0·78 (sem 0·1) μmol/l (59 %), respectively, while the controls consuming the lycopene-restricted diet showed a decline in plasma lycopene concentration from 0·55 (sem 0·60) to 0·42 (sem 0·07) μmol/l ( - 24 %). The end-of-study prostate lycopene concentration was 0·16 (sem 0·02) nmol/g in the controls, but was 3·5-, 3·6- and 2·2-fold higher in tomato soup (P= 0·001), sauce (P= 0·001) and juice (P= 0·165) consumers, respectively. Prostate lycopene concentration was moderately correlated with post-intervention plasma lycopene concentrations (r 0·60, P =0·001), indicating that additional factors have an impact on tissue concentrations. While the primary geometric lycopene isomer in tomato products was all-trans (80-90 %), plasma and prostate isomers were 47 and 80 % cis, respectively, demonstrating a shift towards cis accumulation. Consumption of typical servings of processed tomato products results in differing plasma and prostate lycopene concentrations. Factors including meal composition and genetics deserve further evaluation to determine their impacts on lycopene absorption and biodistribution.