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BACKGROUND: Some, but not all, epidemiologic evidence supports a role for cholesterol, the precursor for steroid hormone synthesis, in prostate cancer. Using a PTEN-null transgenic mouse model of prostate cancer, we tested the effect of modifying serum cholesterol levels on prostate tumor development and growth. We hypothesized that serum cholesterol reduction would lower tumor androgens and slow prostate cancer growth.METHODS: PTENloxP/loxP-Cre+ mice consuming ad libitum high fat, high cholesterol diets (40% fat, 1.25% cholesterol) were randomized after weaning to receive the cholesterol uptake inhibitor, ezetimibe (30 mg/kg/day), or no intervention, and sacrificed at 2, 3, or 4 months of age. Serum cholesterol and testosterone were measured by ELISA and intraprostatic androgens by mass spectrometry. Prostate histology was graded, and proliferation and apoptosis in tumor epithelium and stroma was assessed by Ki67 and TUNEL, respectively.RESULTS: Ezetimibe-treated mice had lower serum cholesterol at 4 months (p = 0.031). Serum cholesterol was positively correlated with prostate weight (p = 0.033) and tumor epithelial proliferation (p = 0.069), and negatively correlated with tumor epithelial apoptosis (p = 0.004). Serum cholesterol was unrelated to body weight (p = 0.195). Tumor stromal cell proliferation was reduced in the ezetimibe group (p = 0.010). Increased serum cholesterol at 4 months was associated with elevated intraprostatic DHEA, testosterone, and androstenedione (p = 0.043, p = 0.074, p = 0.031, respectively). However, cholesterol reduction did not significantly affect adenocarcinoma development at 2, 3, or 4 months of age (0, 78, and 100% in ezetimibe-treated vs. 0, 80, and 100% in mice not receiving ezetimibe).CONCLUSIONS: Though serum cholesterol reduction did not significantly affect the rate of adenocarcinoma development in the PTEN-null transgenic mouse model of prostate cancer, it lowered intraprostatic androgens and slowed tumor growth. These findings support a role for serum cholesterol in promoting prostate cancer growth, potentially via enhanced tumor androgen signaling, and may provide new insight into cholesterol-lowering interventions for prostate cancer treatment.

BACKGROUND Epidemiologic data suggest cholesterol-lowering drugs may prevent the progression of prostate cancer, but not the incidence of the disease. However, the association of combination therapy in cholesterol reduction on prostate or any cancer is unclear. In this study, we compared the effects of the cholesterol lowering drugs simvastatin and ezetimibe alone or in combination on the growth of LAPC-4 prostate cancer in vivo xenografts. METHODS Proliferation assays were conducted by MTS solution and assessed by Student's t-test. 90 male nude mice were placed on a high-cholesterol Western-diet for 7 days then injected subcutaneously with 1 × 105 LAPC-4 cells. Two weeks post-injection, mice were randomized to control, 11 mg/kg/day simvastatin, 30 mg/kg ezetimibe, or the combination and sacrificed 42 days post-randomization. We used a generalized linear model with the predictor variables of treatment, time, and treatment by time (i.e., interaction term) with tumor volume as the outcome variable. Total serum and tumor cholesterol were measured. Tumoral RNA was extracted and cDNA synthesized from 1 ug of total RNA for quantitative real-time PCR. RESULTS Simvastatin directly reduced in vitro prostate cell proliferation in a dose-dependent, cell line-specific manner, but ezetimibe had no effect. In vivo, low continuous dosing of ezetimibe, delivered by food, or simvastatin, delivered via an osmotic pump had no effect on tumor growth compared to control mice. In contrast, dual treatment of simvastatin and ezetimibe accelerated tumor growth. Ezetimibe significantly lowered serum cholesterol by 15%, while simvastatin had no effect. Ezetimibe treatment resulted in higher tumor cholesterol. A sixfold induction of low density lipoprotein receptor mRNA was observed in ezetimibe and the combination with simvastatin versus control tumors. CONCLUSIONS Systemic cholesterol lowering by ezetimibe did not slow tumor growth, nor did the cholesterol independent effects of simvastatin and the combined treatment increased tumor growth. Despite lower serum cholesterol, tumors from ezetimibe treated mice had higher levels of cholesterol. This study suggests that induction of low density lipoprotein receptor is a possible mechanism of resistance that prostate tumors use to counteract the therapeutic effects of lowering serum cholesterol. Prostate © 2016 Wiley Periodicals, Inc.

Dietary factors have a role in stone disease in adults but little is known about the relationship in children. We tested whether diet could alter urine and serum parameters in a pediatric mouse model.We randomized 30 female BALB/c mice at age 3 weeks to mouse chow, a complex carbohydrate Western diet or a high fructose, high sodium Western diet. Body weight was measured twice weekly. Urine was periodically collected and mice were sacrificed on day 30. Samples were pooled to analyze serum and urine electrolyte factors.There was no significant difference in body weights among the groups at any time or in kidney weight at sacrifice (each p0.15). There was no observable increase in urine stone forming analytes across the arms except uric acid, which tended to be higher in the Western diet and high fructose, high sodium Western diet groups. There was a substantial decrease in urinary stone inhibitors (magnesium and citrate), a decrease in urinary potassium and an increase in serum calcium in the 2 Western diet groups.This pilot study suggests that consuming a Western diet, especially one composed of high fructose and sodium, may alter parameters that predispose to stone formation in children by decreasing stone inhibitors. Results require validation in larger studies and ultimately in humans.

Obesity and prostate cancer (PCa) affect substantial proportions of Western society. Mounting evidence, both epidemiologic and mechanistic, for an association between the two is of public health interest. An improved understanding of the role of this modifiable risk factor in PCa etiology is imperative to optimize screening, treatment, and prevention.To consolidate and evaluate the evidence for an epidemiologic link between obesity and PCa, in addition to examining the proposed underlying molecular mechanisms.A PubMed search for relevant articles published between 1991 and July 2012 was performed by combining the following terms: obesity, BMI, body mass index and prostate cancer risk, prostate cancer incidence, prostate cancer mortality, radical prostatectomy, androgen-deprivation therapy, external-beam radiation, brachytherapy, prostate cancer and quality of life, prostate cancer and active surveillance, in addition to obesity, BMI, body mass index and prostate cancer and insulin, insulin-like growth factor, androgen, estradiol, leptin, adiponectin, and IL-6. Articles were selected based on content, date of publication, and relevancy, and their references were also searched for relevant articles.Increasing evidence suggests obesity is associated with elevated incidence of aggressive PCa, increased risk of biochemical failure following radical prostatectomy and external-beam radiotherapy, higher frequency of complications following androgen-deprivation therapy, and increased PCa-specific mortality, although perhaps a lower overall PCa incidence. These results may in part relate to difficulties in detecting and treating obese men. However, multiple molecular mechanisms could explain these associations as well. Weight loss slows PCa in animal models but has yet to be fully tested in human trials.Obesity appears to be linked with aggressive PCa. We suggest clinical tips to better diagnose and treat obese men with PCa. Whether reversing obesity slows PCa growth is currently unknown, although it is an active area of research.

Background Resveratrol (RESV) is a naturally occurring compound that may possess anticancer capabilities in both prostate carcinoma and melanoma. Methods The in vitro and in vivo cytotoxic activity of RESV and 3,5-dihydroxy-4'-acetoxy- trans -stilbene (4-ACE) was tested using cellular assays and a xenograft model. Five prostate carcinoma cell lines were used for in vitro evaluation. A melanoma cell line (Duke melanoma 738 [DM738]) and the prostate carcinoma line CWR22 were used for in vivo experiments. Mice were randomized to osmotic mini pumps with 200 μL of RESV (250 mg/mL), 4-ACE (335 mg/mL), or vehicle (50% dimethyl sulfoxide, 50% polyethylene glycol). Serum drug and metabolite levels were calculated by high-performance liquid chromatography with diode-array detection. Western blots were performed on treated tumors. Results were analyzed using a student’s t-test, analysis of variance, and the Mann–Whitney rank sum test. Results RESV and 4-ACE were cytotoxic in a time- and dose-dependent manner in all prostate carcinoma cell lines tested. Enhanced growth compared with controls was seen at the 24 h time point in four lines treated with RESV and two lines treated with 4-ACE ( P s In vivo , no difference in either tumor growth or postmortem tumor weight was detected in either DM738 ( P = 0.555, P = 0.562) or CWR22 ( P = 0.166, P = 0.811) xenografts treated with either drug. Serum drug levels did not correlate with tumor growth rates for any treatment group (all P s > 0.11). Treated tumors demonstrated protein changes by western blot. Conclusion Although in vitro data were promising, RESV and 4-ACE have limited potential as single agents in the treatment of prostate carcinoma and melanoma.

Epidemiologic data suggest cholesterol-lowering drugs may prevent the progression of prostate cancer, but not the incidence of the disease. However, the association of combination therapy in cholesterol reduction on prostate or any cancer is unclear. In this study, we compared the effects of the cholesterol lowering drugs simvastatin and ezetimibe alone or in combination on the growth of LAPC-4 prostate cancer in vivo xenografts.Proliferation assays were conducted by MTS solution and assessed by Student's t-test. 90 male nude mice were placed on a high-cholesterol Western-diet for 7 days then injected subcutaneously with 1 × 10Simvastatin directly reduced in vitro prostate cell proliferation in a dose-dependent, cell line-specific manner, but ezetimibe had no effect. In vivo, low continuous dosing of ezetimibe, delivered by food, or simvastatin, delivered via an osmotic pump had no effect on tumor growth compared to control mice. In contrast, dual treatment of simvastatin and ezetimibe accelerated tumor growth. Ezetimibe significantly lowered serum cholesterol by 15%, while simvastatin had no effect. Ezetimibe treatment resulted in higher tumor cholesterol. A sixfold induction of low density lipoprotein receptor mRNA was observed in ezetimibe and the combination with simvastatin versus control tumors.Systemic cholesterol lowering by ezetimibe did not slow tumor growth, nor did the cholesterol independent effects of simvastatin and the combined treatment increased tumor growth. Despite lower serum cholesterol, tumors from ezetimibe treated mice had higher levels of cholesterol. This study suggests that induction of low density lipoprotein receptor is a possible mechanism of resistance that prostate tumors use to counteract the therapeutic effects of lowering serum cholesterol. Prostate 77:446-457, 2017. © 2016 Wiley Periodicals, Inc.

BACKGROUND Resveratrol increases lifespan and decreases the risk of many cancers. We hypothesized resveratrol will slow the growth of human prostate cancer xenografts. METHODS SCID mice were fed Western diet (40% fat, 44% carbohydrate, 16% protein by kcal). One week later, human prostate cancer cells, either LAPC-4 (151 mice) or LNCaP (94 mice) were injected subcutaneously. Three weeks after injection, LAPC-4 mice were randomized to Western diet (control group), Western diet plus resveratrol 50 mg/kg/day, or Western diet plus resveratrol 100 mg/kg/day. The LNCaP mice were randomized to Western diet or Western diet plus resveratrol 50 mg/kg/day. Mice were sacrificed when tumors reached 1,000 mm3. Survival differences among groups were assessed using Cox proportional hazards. Serum insulin and IGF axis were assessed using ELISAs. Gene expression was analyzed using Affymetrix gene arrays. RESULTS Compared to control in the LAPC-4 study, resveratrol was associated with decreased survival (50 mg/kg/day—HR 1.53, P = 0.04; 100 mg/kg/day—HR 1.22, P = 0.32). In the LNCaP study, resveratrol did not change survival (HR 0.77, P = 0.22). In combined analysis of both resveratrol 50 mg/kg/day groups, IGF-1 was decreased (P = 0.05) and IGFBP-2 was increased (P = 0.01). Resveratrol induced different patterns of gene expression changes in each xenograft model, with upregulation of oncogenic pathways E2F3 and beta-catenin in LAPC-4 tumors. CONCLUSION Resveratrol was associated with significantly worse survival with LAPC-4 tumors, but unchanged survival with LNCaP. Based on these preliminary data that resveratrol may be harmful, caution should be advised in using resveratrol for patients until further studies can be conducted. Prostate 73: 754–762, 2013. © 2012 Wiley Periodicals, Inc.

Worldwide regional disparities in the occurrence of prostate cancer (PCa) have been attributed in part to the effect of diet, with Asian men having up to a six fold decreased incidence over their western counterparts [1]. Epidemiologic observations, however, have been inconclusive about which specific dietary components contribute to PCa [2–5]. A logical extension is that if diet can affect the development of cancer, it can also influence the growth of an established tumor, and indeed this has been demonstrated in animal studies [6–9]. While traditionally a low fat diet was thought to be optimal, we previously hypothesized that a reduced carbohydrate diet was likewise beneficial [10]. In a prior study we found that mice consuming a no-carbohydrate ketogenic diet (NCKD) had increased overall survival and slower tumor growth, compared to mice on a western diet, a benefit not observed in mice consuming a low fat diet [11]. These findings were then replicated in a similar xenograft model with the finding that a low-fat diet was also beneficial [12]. The favorable effect in the NCKD mice was thought to be from decreased signaling of the insulin/ insulin-like growth factor (IGF) axis, a pathway integral in the progression of PCa [8, 10, 13–18]. These provocative results were further explored by another group with diets not completely devoid of carbohydrates, but rather with lower proportions (such as might be reasonably tolerated in human subjects) which have also been shown to delay tumor growth in a prostate xenograft model [19]. However, in that prior study a low-carbohydrate diet was not directly compared to a NCKD. To address this, we recently tested low-carbohydrate diets (10 and 20% carbohydrate kcals, respectively) vs. a NCKD in a mouse xenograft model and found all carbohydrate restricted diets had similar effects on tumor growth, overall survival, and IGF axis signaling, suggesting that low carbohydrate diets may be as effective as a NCKD [20]. While these dietary changes appear to be promising for slowing tumor growth, the best established therapy for stunting PCa involves chemical or surgical castration. The deleterious effects of androgen deprivation on weight, diabetes and cardiovascular health make dietary decisions under this circumstance of particular interest [21–23]. Thus we sought to explore the effect of low- and no-carbohydrate diets on tumor growth and survival as an adjunct to androgen deprivation therapy in a PCa xenograft model.

The purpose of this study is to investigate the effects of exercise on cancer progression, metastasis, and underlying mechanisms in an orthotopic model of murine prostate cancer. C57BL/6 male mice (6–8 wk of age) were orthotopically injected with transgenic adenocarcinoma of mouse prostate C-1 cells (5 × 105) and randomly assigned to exercise ( n = 28) or a non-intervention control ( n = 31) groups. The exercise group was given voluntary access to a wheel 24 h/day for the duration of the study. Four mice per group were serially killed on days 14, 31, and 36; the remaining 38 mice (exercise, n = 18; control, n = 20) were killed on day 53. Before death, MRI was performed to assess tumor blood perfusion. Primary tumor growth rate was comparable between groups, but expression of prometastatic genes was significantly modulated in exercising animals with a shift toward reduced metastasis. Exercise was associated with increased activity of protein kinases within the MEK/MAPK and PI3K/mTOR signaling cascades with subsequent increased intratumoral protein levels of HIF-1α and VEGF. This was associated with improved tumor vascularization. Multiplex ELISAs revealed distinct reductions in plasma concentrations of several angiogenic cytokines in the exercise group, which was associated with increased expression of angiogenic and metabolic genes in the skeletal muscle. Exercise-induced stabilization of HIF-1α and subsequent upregulation of VEGF was associated with “productive” tumor vascularization with a shift toward suppressed metastasis in an orthotopic model of prostate cancer.

What's known on the subject? and What does the study add? It is known that both lactate inhibition and carbohydrate restriction inhibit tumour growth. What is unknown is whether the two work synergistically together. This study adds that though the combination of lactate inhibition and carbohydrate restriction did not synergistically slow tumour growth in our model, we confirmed that carbohydrate restriction started after tumour inoculation slowed tumour growth. Moreover, lactate inhibition resulted in changes in the tumour microenvironment that may have implications for future metabolic targeting of prostate cancer growth. OBJECTIVE • To determine if a no-carbohydrate ketogenic diet (NCKD) and lactate transporter inhibition can exert a synergistic effect on delaying prostate tumour growth in a xenograft mouse model of human prostate cancer. MATERIALS AND METHODS • 120 nude athymic male mice (aged 6–8 weeks) were injected s.c. in the flank with 1.0 × 105 LAPC-4 prostate cancer cells. • Mice were randomized to one of four treatment groups: Western diet (WD, 35% fat, 16% protein, 49% carbohydrate) and vehicle (Veh) treatment; WD and mono-carboxylate transporter-1 (MCT1) inhibition via α-cyano-4-hydroxycinnamate (CHC) delivered through a mini osmotic pump; NCKD (84% fat, 16% protein, 0% carbohydrate) plus Veh; or NCKD and MCT1 inhibition. • Mice were fed and weighed three times per week and feed was adjusted to maintain similar body weights. • Tumour size was measured twice weekly and the combined effect of treatment was tested via Kruskal–Wallis analysis of all four groups. Independent effects of treatment (NCKD vs WD and CHC vs Veh) on tumour volume were tested using linear regression analysis. • All mice were killed on Day 53 (conclusion of pump ejection), and serum and tumour sections were analysed for various markers. Again, combined and independent effects of treatment were tested using Kruskal–Wallis and linear regression analysis, respectively. RESULTS • There were no significant differences in tumour volumes among the four groups (P= 0.09). • When testing the independent effects of treatment, NCKD was significantly associated with lower tumour volumes at the end of the experiment (P= 0.026), while CHC administration was not (P= 0.981). However, CHC was associated with increased necrotic fraction (P < 0.001). CONCLUSIONS • Differences in tumour volumes were observed only in comparisons between mice fed a NCKD and mice fed a WD. • MCT1 inhibition did not have a significant effect on tumour volume, although it was associated with increased necrotic fraction.

Previous studies indicate that carbohydrate intake influences prostate cancer biology, as mice fed a no-carbohydrate ketogenic diet (NCKD) had significantly smaller xenograft tumors and longer survival than mice fed a Western diet. As it is nearly impossible for humans to consume and maintain NCKD, we determined whether diets containing 10% or 20% carbohydrate kcal showed similar tumor growth as NCKD. A total of 150 male severe combined immunodeficient mice were fed a Western diet ad libitum, injected with the human prostate cancer cell line LAPC-4, and then randomized 2 weeks later to one of three arms: NCKD, 10% carbohydrate, or 20% carbohydrate diets. Ten mice not injected were fed an ad libitum low-fat diet (12% fat kcal) serving as the reference in a modified-paired feeding protocol. Mice were sacrificed when tumors reached 1,000 mm3. Despite consuming extra calories, all mice receiving low-carbohydrate diets were significantly lighter than those receiving a low-fat diet (P < 0.04). Among the low-carbohydrate arms, NCKD-fed mice were significantly lighter than the 10% or 20% carbohydrate groups (P < 0.05). Tumors were significantly larger in the 10% carbohydrate group on days 52 and 59 (P < 0.05), but at no other point during the study. Diet did not affect survival (P = 0.34). There were no differences in serum insulin-like growth factor-I or insulin-like growth factor binding protein-3 at sacrifice among the low-carbohydrate arms (P = 0.07 and P = 0.55, respectively). Insulin was significantly lower in the 20% carbohydrate arm (P = 0.03). LAPC-4 xenograft mice fed a low-carbohydrate diet (10–20% carbohydrate kcal) had similar survival as mice consuming NCKD (0% carbohydrate kcal). Cancer Prev Res; 3(9); 1124–31. ©2010 AACR.

Previous mouse studies suggesting that low fat diets slow prostate cancer growth often used corn oil (omega-6), which enhances prostate cancer growth, as the primary fat. Using a saturated fat based diet we previously found no significant difference in tumor growth between low and high fat fed SCID mice (Taconic Farms, Hudson, New York) xenografted with LAPC-4 cells. Whether similar results would hold in a castration model is unclear.A total of 80 male SCID mice were fed a Western diet (40% fat and 44% carbohydrate) and injected with LAPC-4 human prostate cancer cells. When tumors were 200 mm(3), the mice were castrated and randomized to an isocaloric Western or a low fat diet (12% fat and 72% carbohydrate). Animals were sacrificed when tumors were 1,000 mm(3). Serum was collected and assayed for prostate specific antigen, insulin, insulin-like growth factor 1 and insulin-like growth factor binding protein 3. Tumors were assayed for total and phosphorylated Akt.Mouse weight was equivalent in the 2 groups. Overall dietary group was not significantly associated with survival (log rank p = 0.32). There were no statistically significant differences in prostate specific antigen (p = 0.53), insulin-like growth factor axis parameters (each p0.05) or p-Akt-to-t-Akt ratios (p = 0.22) between the groups at sacrifice.In this xenograft model we found no difference in tumor growth or survival between low fat vs Western fed mice when the fat source was saturated fat. These results conflict with those of other studies in which corn oil was used to show that low fat diets delay prostate cancer growth, suggesting that fat type may be as important as fat amount in the prostate cancer setting.

The flux through the de novo pyrimidine biosynthetic pathway is controlled by the multifunctional protein CAD, which catalyzes the first three steps. The cell cycle dependent regulation of pyrimidine biosynthesis is a consequence of sequential phosphorylation of CAD Thr456 and Ser1406 by the MAP kinase and PKA cascades, respectively. Coordinated regulation of the pathway requires precise timing of the two phosphorylation events. These studies show that phosphorylation of purified CAD by PKA antagonizes MAP kinase phosphorylation, and vice versa. Similar results were observed in vivo. Forskolin activation of PKA in BHK-21 cells resulted in a 8.5 fold increase in Ser1406 phosphorylation and severely curtailed the MAP kinase mediated phosphorylation of CAD Thr456. Moreover, the relative activity of MAP kinase and PKA was found to determine the extent of Thr456 phosphorylation. Transfectants expressing elevated levels of MAP kinase resulted in a 11-fold increase in Thr456 phosphorylation, whereas transfectants that overexpress PKA reduced Thr456 phosphorylation 5-fold. While phosphorylation of one site by one kinase may induce conformational changes that interfere with phosphorylation by the other, the observation that both MAP kinase and PKA form stable complexes with CAD suggest that the mutual antagonism is the result of steric interference by the bound kinases. The reciprocal antagonism of CAD phosphorylation by MAP kinase and PKA provides an elegant mechanism to coordinate the cell cycle-dependent regulation of pyrimidine biosynthesis ensuring that signals for up- and down-regulation of the pathway do not conflict.

The relationship between aging, the development of benign prostatic hyperplasia (BPH), and lower urinary tract symptoms (LUTS) has been well described. Briefly, BPH may lead to increased bladder outlet obstruction and compensatory changes in the bladder. Eventually these changes may manifest as LUTS (eg, frequency, urgency, nocturia) and ultimately lead to a diminished quality of life and an increased risk for depression, falls, and mortality as nicely reviewed by Parsons et al in this issue of the journal [1]. Aside from quality-of-life measures, the medical and surgical management of LUTS creates significant costs to the health system. Due to increasing cost constraints, methods of primary prevention for LUTS are attractive. Another chronic medical condition that increases medical costs and has become epidemic in both the United States and Europe is obesity. Growing evidence suggests that elderly men with higher body mass index (BMI) are at increased risk for the development of LUTS, although other studies suggest no association between BMI and LUTS. Whereas the Baltimore Longitudinal Aging Study found that men with higher BMI were at higher risk for the development of BPH [2], another study found no association between anthropometric measures at baseline and the subsequent development of LUTS [3]. Data from the Health Professionals Follow-up Study showed that men with higher BMI and men with higher levels of abdominal obesity were more likely to undergo prostatectomy, and among men who did not have a prostatectomy, higher BMI was associated with urinary frequency [4]. Finally, data from a 2008 meta-analysis of 11 previous studies found that increased physical activity was associated with reduced risk of BPH and LUTS [5]. Although most men who live long enough will have BPH, not all men will experience LUTS (ie, symptoms). Further investigation of the relationships between physical activity level, obesity, and the development of LUTS may help identify men at higher risk for LUTS who may benefit from lifestyle modifications. The current report by Parsons et al describes the risk of developing LUTS over a mean 4.6-yr follow-up in a prospective cohort of 1695 men from the Osteoporotic Fractures in Men Study (MrOS) who were 65–91 yr of age [1]. They found that overweight and obese men had a 29% and 41% higher risk of developing LUTS when compared with men with BMI

Previous mouse studies suggest that decreasing dietary fat content can slow prostate cancer (PCa) growth. To our knowledge, no study has yet compared the effect of multiple different fats on PCa progression. We sought to systematically compare the effect of fish oil, olive oil, corn oil and animal fat on PCa progression.A total of 96 male severe combined immunodeficient mice were injected with LAPC-4 human PCa cells. Two weeks following injection, mice were randomized to a Western diet based on fish oil, olive oil, corn oil or animal fat (35% kilocalories from fat). Animals were euthanized when tumor volumes reached 1000 mm(3). Serum was collected at death and assayed for PSA, insulin, insulin-like growth factor-1 (IGF-1), IGF-1-binding protein-3 and prostaglandin E-2 (PGE-2) levels. Tumors were also assayed for PGE-2 and cyclooxygenase-2 levels, and global gene expression was analyzed using Affymetrix microarrays.Mice weights and tumor volumes were equivalent across groups at randomization. Overall, fish oil consumption was associated with improved survival relative to other dietary groups (P=0.014). On gene expression analyses, the fish oil group had decreased signal in pathways related to mitochondrial physiology and insulin synthesis/secretion.In this xenograft model, we found that consuming a diet in which fish oil was the only fat source slowed tumor growth and improved survival compared with that in mice consuming diets composed of olive oil, corn oil or animal fat. Although prior studies showed that the amount of fat is important for PCa growth, this study suggests that the type of dietary fat consumed may also be important.

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 macroand 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 metaanalyses 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 v-6 fats, and certain vitamin supplements may promote PCa risk and progression. Conversely, consumption of many plant phytochemicals and v-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.

Resveratrol increases lifespan and decreases the risk of many cancers. We hypothesized resveratrol will slow the growth of human prostate cancer xenografts.SCID mice were fed Western diet (40% fat, 44% carbohydrate, 16% protein by kcal). One week later, human prostate cancer cells, either LAPC-4 (151 mice) or LNCaP (94 mice) were injected subcutaneously. Three weeks after injection, LAPC-4 mice were randomized to Western diet (control group), Western diet plus resveratrol 50 mg/kg/day, or Western diet plus resveratrol 100 mg/kg/day. The LNCaP mice were randomized to Western diet or Western diet plus resveratrol 50 mg/kg/day. Mice were sacrificed when tumors reached 1,000 mm(3). Survival differences among groups were assessed using Cox proportional hazards. Serum insulin and IGF axis were assessed using ELISAs. Gene expression was analyzed using Affymetrix gene arrays.Compared to control in the LAPC-4 study, resveratrol was associated with decreased survival (50 mg/kg/day--HR 1.53, P = 0.04; 100 mg/kg/day--HR 1.22, P = 0.32). In the LNCaP study, resveratrol did not change survival (HR 0.77, P = 0.22). In combined analysis of both resveratrol 50 mg/kg/day groups, IGF-1 was decreased (P = 0.05) and IGFBP-2 was increased (P = 0.01). Resveratrol induced different patterns of gene expression changes in each xenograft model, with upregulation of oncogenic pathways E2F3 and beta-catenin in LAPC-4 tumors.Resveratrol was associated with significantly worse survival with LAPC-4 tumors, but unchanged survival with LNCaP. Based on these preliminary data that resveratrol may be harmful, caution should be advised in using resveratrol for patients until further studies can be conducted.

dicted miR221-targets being able to repress STAT1 signaling and confirmed these by Luciferase assay and Western Blotting. RT-PCR analysis of gene expression in native tumors were performed to proof the correlation between IRF1, IRF2 and miR-221 levels. RESULTS: Transfection of cells (PC3,DU145,LNCaP) with premiR-221 led to a strong induction of apoptosis and a significant growth arrest. Microarray-based genome-wide mRNA profiling showed an upregulation of 585 genes–among these a plethora of interferonrelated genes–and downregulation of 306 genes. Bioinformatical annotation of microarray data confirmed a highly significant involvement of genes related to immune response and apoptosis. Furthermore,expression of dysregulated genes was confirmed by RT-PCR (STAT1, IRF1, IRF9) and Western Blotting (STAT1, Phospho-STAT1, Phospho-PKR). To understand how reconstitution of miR221 enhances STAT1-mediated signaling, we were looking for bioinformatically predicted miR221-targets being able to repress STAT1 signaling. We introduce IRF2 as a new direct target of miR221 using Luciferase assay and Western Blotting. Consistently, RT-PCR analysis of gene expression in native tumors showed an inverse correlation between IRF1 and IRF2 with a significantly low expression of IRF2 in tumors with high miR221-levels. CONCLUSIONS: Our results suggest that the tumor-suppressive function of miR221 bases on the repression of IRF2, an antagonist of the STAT1-IRF1 signaling axis and known oncogene in other malignancies.

Prostate cancer (PC) is the second leading cause of cancer death in men. Recent reports suggest that excess of nutrients involved in the one-carbon metabolism pathway increases PC risk; however, empirical data are lacking. Veteran American men (272 controls and 144 PC cases) who attended the Durham Veteran American Medical Center between 2004–2009 were enrolled into a case-control study. Intake of folate, vitamin B12, B6, and methionine were measured using a food frequency questionnaire. Regression models were used to evaluate the association among one-carbon cycle nutrients,MTHFRgenetic variants, and prostate cancer. Higher dietary methionine intake was associated with PC risk (OR = 2.1; 95%CI 1.1–3.9) The risk was most pronounced in men with Gleason sum MTHFRA1298C allele (OR=6.7; 95%CI = 1.6–27.8), compared toMTHFRA1298A noncarrier men (OR=0.9; 95%CI = 0.24–3.92) (p-interaction=0.045). There was no evidence for associations between B vitamins (folate, B12, and B6) and PC risk. Our results suggest that carrying theMTHFRA1298C variants modifies the association between high methionine intake and PC risk. Larger studies are required to validate these findings.

INTRODUCTION AND OBJECTIVES: African-American men (AAM) are at higher risk for prostate cancer (PC) vs. Caucasian men (CM). The cause is likely multi-factorial. Though alcohol intake as a PC risk factor in the overall population is controversial, we recently reported that, among men undergoing prostate biopsy, alcohol intake was associated with increased PC risk only among AAM. Polymorphisms of the alcohol dehydrogenase (ADH) gene, that lead to bodily accumulation of acetaldehyde a carcinogen, occur more frequently in AAM. Whether these alleles interact with alcohol exposure to promote PC development is unknown. METHODS: DNA and alcohol intake surveys were obtained from 347 men from the Durham VA Hospital who underwent prostate biopsy (n 199) or were hospital-based controls (n 148 with no indication for biopsy) from 2007 to 2010. The DNA was genotyped for ADH1B*3 and dichotomized into carriers of the common allele (ADH1B*3-; C/C) and the variant allele (ADH1B*3 ; C/T or T/T). Alcohol intake was dichotomized into non-drinker and alcohol drinker. Two separate logistic regression models, adjusting for clinical covariates, were conducted: 1) Only among men who underwent a biopsy; 2) Comparing men with cancer on biopsy to the controls. RESULTS: A total of 60 (13%) men were heterozygous and 11 (2%) were homozygous for ADH1B*3. Nearly all ADH1B*3 subjects were AAM (n 69; 97%) with 35% of AAM carrying the variant allele. ADH1B*3 alcohol drinkers were 4 times more likely to have a positive biopsy than ADH1B*3non-drinkers (OR 3.7, 95%CI 1.0– 13.3). In crude analysis comparing biopsy men to controls, ADH1B*3 alcohol drinkers were 5 times more likely to have PC than ADH1B*3non-drinkers. There was a trend for increased PC risk among ADH1B*3 alcohol drinkers in multivariate analyses which did not reach statistical significance (p 0.11). In all models, PC risk for ADH1B*3 non-drinkers and ADH1B*3alcohol drinkers were not different from ADH1B*3non-drinkers. CONCLUSIONS: Our preliminary findings suggest the ADH1B*3 variant allele and alcohol intake is a novel gene-environment interaction for PC risk, nearly unique to AAM. If confirmed, this geneenvironment interaction may help explain increased PC risk in AAM who consume alcohol, while no effect is seen in CM.

Caloric restriction (CR) has been shown to have anti-cancer properties. However, CR may be difficult to apply in humans secondary to compliance and potentially deleterious effects. An alternative is intermittent CR, or in the extreme case intermittent fasting (IF). In a previous small pilot study, we found 2 days per week of IF with ad libitum feeding on the other days resulted in trends toward prolonged survival of mice bearing prostate cancer xenografts. We sought to confirm these findings in a larger study. A total of 100 (7- to 8-week-old) male severe combined immunodeficiency mice were injected subcutaneously with 1 × 10(5) LAPC-4 prostate cancer cells. Mice were randomized to either ad libitum Western Diet (44% carbohydrates, 40% fat and 16% protein) or ad libitum Western Diet with twice-weekly 24 h fasts (IF). Tumor volumes and mouse bodyweights were measured twice weekly. Mice were killed when tumor volumes reached 1000 mm(3). Serum and tumor were collected for analysis of the insulin/insulin-like growth factor 1 (IGF-1) hormonal axis. Overall, there was no difference in mouse survival (P=0.37) or tumor volumes (P ≥ 0.10) between groups. Mouse body weights were similar between arms (P=0.84). IF mice had significantly higher serum IGF-1 levels and IGF-1/IGFBP-3 ratios at killing (P

Obesity is one of the biggest public health crises of our day. In the United States, 1 in 3 adult men is obese. This rate is staggeringly high compared with obesity rates in other countries—notably those in Asia, where obesity rates are

Introduction: Western countries have 6 fold higher incidence of prostate cancer (PC). Dietary composition, in addition to other factors, may contribute to this geographic disparity. Cholesterol, the precursor for de novo steroid hormone synthesis, has been hypothesized to promote PC growth via multiple pathways including intratumoral steroidogenesis. While lowering serum cholesterol slows xenograft PC growth, this has not been tested in transgenic models, which allow testing of PC prevention as well as modulating PC growth in an orthotopic position. We determined the effect of cholesterol uptake inhibition, using ezetimibe, on PC growth in Hi-Myc and PTEN transgenic mice. Methods: We randomized 50 c-myc/wt (Hi-Myc) mice and 30 PTENloxP/loxP-Cre+ (PTEN) to one of two diets: high fat high cholesterol (HFHC; 40% fat, 17% protein, 43% carbohydrate, 1.25% cholesterol), or HFHC with ezetimibe (30 mg/kg food) (HFHC+Z). Mice were fed ad libitum starting right after weaning and body weights measured twice weekly. Prostate, liver, spleen, adipose tissue and serum were harvested from Hi-Myc and PTEN mice at age 6 and 4 months, respectively. Serum cholesterol and testosterone (T) and tumor T were measured in Hi-Myc mice and are ongoing in PTEN mice. Results: In Hi-Myc mice, body weights were significantly greater in the HFHC+Z group at sacrifice, relative to the HFHC group (p=0.04), but there were no differences in prostate weight between groups with adjustment for body weight (p=0.84). In PTEN mice, there was no difference in body weights between groups, but prostate weight was significantly lower in the HFHC+Z group, relative to the HFHC group (p=0.046). In Hi-Myc mice, while serum T levels did not vary between groups (p=0.93), tumor T, dihydrotestosterone (DHT) and androstenedione concentrations were significantly reduced in the HFHC+Z group, relative to the HFHC group (p=0.01, p=0.01, p=0.006, respectively). Discussion: Reduction of serum cholesterol levels using cholesterol uptake inhibitor, ezetimibe, significantly reduced prostate weight in PTEN mice consuming a HFHC diet. Furthermore, supplementation of the HFHC diet with ezetimibe significantly reduced tumor concentrations of T, DHT and androstenedione in Hi-Myc mice, although there was no effect on prostate weight. These findings highlight a potentially critical role for cholesterol in PC progression by providing evidence that reduction of hypercholesterolemia may reduce intratumoral de novo steroidogenesis and slow PC growth. This study may provide new insight into the use of cholesterol-lowering drugs for PC prevention and treatment. Citation Format: Emma H. Allott, Elizabeth M. Masko, Alexa Choy, Alexis R. Gaines, Keith R. Solomon, Salvatore V. Pizzo, Stephen J. Freedland. Inhibition of cholesterol uptake with ezetimibe reduces intra-tumoral testosterone levels and slows tumor growth in transgenic mouse models of prostate cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3698. doi:10.1158/1538-7445.AM2013-3698

Introduction: Preclinical studies have shown that dietary carbohydrate restriction slows prostate tumor growth in multiple xenograft models in part due to a reduction insulin-like growth factor (IGF) axis signaling. Pomegranate extract (PE) has been shown to slow prostate tumor growth in-vitro and in vivo similarly through this pathway, as well as decrease markers of angiogenesis and inflammation. In this study, we determined the dose-response of PE on prostate tumor growth in the setting of dietary carbohydrate restriction in a slow-growing mouse xenograft model. For this study, we chose a standardized PE (POMx, Pom Wonderful, Los Angeles, CA), at doses which are easily translatable to human equivalents. Materials and Methods: Male athymic nude mice housed 5 per cage (n = 130) were subcutaneously injected with 1 × 10^5 LAPC-4 cells after a 10 day acclimation period. 14 days post-injection, all mice were all placed on an ad-libitum no-carbohydrate ketogenic diet (NCKD: 83% fat, 0% carbohydrate, 17% protein) (day 0). Each cage was randomly assigned to 1 of 4 doses of PE (placebo = 0 mg, low dose = 2.62 mg, intermediate dose = 5.25mg, or high dose = 7.87mg) suspended in 0.2 mL of PBS delivered via oral gavage 5 days per week. These doses are equivalent to 0, 1, 2, or 3 POMx capsules/day consumed by a 70 kg human. Mice will be sacrificed when tumors reach ≥1,000 mm^3. Results: At randomization, there were no differences in median body weight among groups (p = 0.623). Currently, at day 32, overall survival is decreased in the placebo group (hazard ratio 2.26, 95% confidence interval, 0.83 - 6.10, p = 0.109) relative to the low dose PE group with no survival differences among PE groups. Median tumor volumes for the placebo group are 83.3mm^3, compared to 74.5mm^3, 76.3mm^3, and 70.1mm^3 for the low, intermediate, and high PE doses respectively, which are not statistically different (p = 0.98). Conclusions: Preliminary data show a trend toward improved survival with the combination of an NCKD and PE at the selected doses. Currently, tumor volumes are not significantly different, however completed results will be presented. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5631. doi:1538-7445.AM2012-5631

Introduction: Methionine restriction has been shown to have growth inhibitory effects in a number of tumor cell lines in vitro. Methionine restriction has previously been demonstrated to slow PC-3 prostate tumor cell growth in vivo, however not at dietary levels tolerable to humans. Up to 90% dietary methionine restriction has been demonstrated to be both tolerable and safe in a preliminary human clinical trial. We hypothesized that 80%-90% methionine restriction could limit prostate tumor cell growth in vitro and in vivo. Methods: We reduced methionine levels by 40%, 80%, 90% and 100% in prostate cancer cell lines in vitro, relative to standard RPMI medium. Cell proliferation and viability were measured using MTS and trypan blue assays, respectively. PC-3 cells were grafted into a xenograft nude mouse model and animals were randomized to standard chow, 80% or 90% methionine restricted diets. Plasma methionine levels were measured before and after the dietary intervention. Tumor volume was measured throughout the study and mice were sacrificed when tumors reached 1000 mm3. Results: Methionine restriction exerted a dose and time-dependent effect on PC-3 tumor cell proliferation and viability in vitro. Methionine restriction of 80% and 90% for a period of 6 days reduced PC-3 tumor cell line proliferation by 20% and 40%, respectively, as measured by MTS assay (p Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5255. doi:1538-7445.AM2012-5255

Background: Epidemiologic data suggest cholesterol-lowering drugs may prevent the progression of prostate cancer (PC), but not the incidence of the disease. This may occur by lowering levels of low-density lipoproteins (LDL). Statins and cholesterol-uptake inhibitors like ezetimibe lower serum LDL and are commonly prescribed for patients with high cholesterol. In this study, we determined the therapeutic role of simvastatin, ezetimibe, or both in vitro using several PC cell lines and in vivo using a LAPC-4 xenograft model. Methods: We treated 4 PC cell lines (LAPC-4, CWR22rv1, PC-3, and DU145) with varying concentrations of simvastatin (0-1000nM) or ezetimibe (0-100μM) for 0-5 days. MTS assays were performed to determine cell proliferation, and the IC50 was calculated using BioDataFit 1.02. For our in vivo study, a total of 90 athymic male nude mice were fed a high-fat, high-cholesterol diet (HFHC; 40% fat, 17% protein, 43% carbohydrates, 1.25% cholesterol), subcutaneously injected with 1 x 10^5 LAPC-4 cells, and randomized 2 weeks later to 1 of 4 treatments: vehicle control, 11mg/kg/day simvastatin (delivered via osmotic pump), 30mg/kg diet ezetimibe (delivered in the food), or simvastatin + ezetimibe. Mice remained on study for 42 days post-randomization, at which point they were harvested and samples analyzed. Results: In vitro, simvastatin directly reduced PC cell proliferation in a dose-dependent, cell line-specific manner, but ezetimibe had no inhibitory effect. In vivo, treatment of low continuous dosing of simvastatin or ezetimibe for 42 days had no effect on tumor growth compared to control. However, relative to control, the combination of simvastatin and ezetimibe accelerated tumor growth (p=0.01). The simvastatin-ezetimibe mice also showed lower fat infiltration in the liver and lower serum cholesterol, but higher tumor cholesterol levels than control. Conclusions: Our results suggest that low continuous dosing of simvastatin or ezetimibe may have no effect on PC growth in a slow-growing LAPC-4 xenograft model, but the combination of simvastatin and ezetimibe may accelerate PC growth, possibly by stimulating cholesterol uptake within the tumor. This novel finding may be important in implementing new treatments for men with slow growing PC and high cholesterol. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3220. doi:1538-7445.AM2012-3220

Introduction and Objectives: Prostate cancer (PC) is affected by cholesterol metabolism and cholesterol-mediating medications. Ezetimibe, a gut cholesterol-uptake inhibitor, inhibits angiogenesis in human PC xenografts when given as preventive therapy. We investigated the effect of ezetimibe on PC growth when given as treatment therapy. Methods: We randomized 125 SCID mice into three initial diets: a high-fat, low-cholesterol diet (HFLC) (40% fat, 43% carbohydrates, 17% protein, 0.21% cholesterol), a high-fat, high-cholesterol diet (HFHC) (40% fat, 43% carbohydrates, 17% protein, 1.25% cholesterol), and a high-fat, high-cholesterol diet supplemented with ezetimibe (30mg/kg) (HFHC+Z). Mice were fed ad libitum. After two weeks, we injected 106 LNCaP cells into the flanks, with 5-10 mice/group serving as non-injected controls. At two weeks post-injection, half the injected and control mice in the HFHC diet group had ezetimibe added to their diet (HFHC+delayed Z). Tumor volumes and body weights were measured twice weekly. Mice were sacrificed once tumors reached 1000mm3. Body weights and tumor volumes were compared across groups using Kruskal-Wallis test. Interim survival outcomes for this on-going study up to 86 days post-injection were evaluated with Cox proportional hazards. Results: At 1 day prior to injection, there were no significant differences in body weights across groups. At post-injection day (PD) 2, HFHC+Z mice with tumors were significantly lighter vs. all other mice (p=0.009). By PD 21, HFHC+delayed Z mice with tumors also became significantly lighter vs. the HFLC and HFHC mice with tumors (p Conclusion: Preliminary evidence from this on-going study demonstrates that ezetimibe is associated with weight loss, but only in mice with PC xenografts. The administration of ezetimibe as preventive vs. treatment therapy does not appear to affect tumor growth or survival. Future studies to explore the interplay between cholesterol metabolism and PC include comparing serum levels of cholesterol, insulin, IGF-1, and IGFBP-3, and tumor markers of proliferation and angiogenesis including akt, pakt, mTOR, VEGF, HIF, CD31 (microvessel density) and ki67 (proliferation). Moreover, we are continuing to follow the mice for any differences in tumor growth or survival. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4602. doi:10.1158/1538-7445.AM2011-4602

Background: Pomegranate extract (POM) has been shown to slow prostate cancer (PC) growth in xenograft models. However, mice in these studies ate standard mouse chow, which is very low-fat (∼12% kcals) and not representative of the typical diet for men with PC. Whether POM slows PC growth when taken with a Western diet is unknown. As our group showed diet to separately affect PC xenograft growth, with a no-carbohydrate ketogenic diet (NCKD) being protective vs. a Western diet, we tested the effects of POM on PC growth and survival in mice fed a Western or NCK diet. Methods: 120 male athymic nude mice (age 6-8 weeks) were fed an ad libitum Western diet and injected subcutaneously with 1×10⁁6 LAPC-4 cells. Two weeks later, mice were randomized to remain on Western diet alone or switched to Western diet + POM, NCKD alone, or NCKD + POM treatments (n=30 per arm). Western diet mice were fed ad libitum and NCKD mice via a modified pair-feeding protocol. POM arms received gavage with 0.8 mg POMx extract (PomWonderful) Monday-Friday and control mice received PBS (0.2 mL all arms). Mice were sacrificed when tumors exceeded 1,000 mm⁁3. Tumor volumes were compared between arms using Kruskal-Wallis. Survival between arms was tested using Cox proportional hazards. Results: The study is currently on-going and results are preliminary for day 53 post-injection. To date, significant differences in tumor volume have been noted across the study arms (p=0.007) with NCKD + POM mice having significantly smaller tumors than mice fed base Western diet (p=0.03). In mice fed NCKD, the addition of POM resulted in a trend toward smaller tumors (p=0.07). In contrast, in mice on Western diet, the addition of POM resulted in a trend toward larger tumors (p=0.13). Diet type alone did not affect tumor volume (p=1.00). Preliminary survival data suggest that treatment group impacted survival (p=0.055). Specifically, survival for the NCKD + POM arm was better than either Western + POM or NCKD alone arms (all p Conclusion: In a xenograft mouse model, the combination of POM and dietary carbohydrate restriction slows PC tumor growth relative to a control Western diet and improves survival vs. either POM or NCKD treatments alone. Interestingly, our data show that POM delays tumor growth in mice fed NCKD but may actually accelerate tumor growth in mice fed a Western diet. Prior pomegranate studies reporting delayed tumor growth utilized very low-fat diets, which we have also shown to slow tumor growth vs. a Western diet, while our findings suggest that dietary background may profoundly influence the effect of pomegranate extract on PC tumor growth and survival. This is especially important given that men with PC are more likely to consume a Western diet. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4611. doi:10.1158/1538-7445.AM2011-4611

INTRODUCTION: Single nucleotide polymorphisms (SNPs) are single nucleotide variations that occur within alleles among individuals. It is believed that SNPs may predispose a person to diseases such as obesity or cancer. One study showed that SNPs within genes linked with obesity were also associated with breast cancer risk. As prostate cancer (PC) mortality is linked with obesity, we determined if SNPs within 5 obesity-related genes were also linked to PC risk in a similar manner to the breast cancer study. METHODS: A total of 53 SNPs were tagged in the genes ADBR2, ADBR3, GHRL, HSD11B1, and SHC1 using the program HAPMAP. DNA collected from 216 subjects (108 incident cases, 108 “healthy” controls) from the Durham VA Hospital were then genotyped for these SNPs. Cases and controls were frequency matched on age and BMI. Logistic regression models were used to determine the risk of obesity (BMI >30 kg/m2) and PC (and high-grade defined as Gleason >7 vs. low-grade/control) for each SNP, adjusting for age and race. RESULTS: In our study population, 83 men were Caucasian and 133 African American. There was no significant differences in age (p=0.18), race (p=0.96), and BMI (p=0.12) for cases and controls. Among the 53 SNPs genotyped, 5 SNPs in ADRB2, ADRB3, and SHC1 were associated with an increased risk of PC (OR 1.88-2.21; p=0.01-0.04), particularly high-grade disease (OR 2.50-3.26; p=0.0004-0.05). Another 4 SNPs in ADRB2 and HSD11B1 were associated with a decreased risk of PC (p=0.01-0.05). A total of 7 SNPs were associated with an increased risk of obesity (p=0.004-0.02). CONCLUSION: In this small pilot study, we found 14 of the 53 analyzed single SNPs in genes previously linked with obesity that were associated with PC risk, both positively and negatively at an alpha of Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2767. doi:10.1158/1538-7445.AM2011-2767

Introduction and Objective: In multiple previous studies, we have shown that mice injected with subcutaneous prostate cancer cells (LNCaP or LAPC-4) and fed a no-carbohydrate ketogenic diet (NCKD, 84% fat, 0% carbohydrate, 16% protein) have significantly decreased tumor volume and significantly prolonged survival, compared to mice fed a western diet (WD, 40% fat, 44% carbohydrate, 16% protein). All previous studies utilized a human prostate cancer cell line, requiring the use of immunodeficient mice. We sought to replicate these previous studies to determine whether diet affected tumor progression and survival in an immunocompetent model. Methods: In this treatment model, 75 male C57bl/6 mice were initially fed WD ad libitum for a period of 14 days. After this 14 day period, all mice were injected subcutaneously with 2.5×105 TRAMP cells and randomized to one of three diets: WD, NCKD, or low-fat diet (LF, 12% fat, 72% carbohydrate, 16% protein). Mice receiving LF diet were fed ad libitum, and served as the reference group in paired-feeding protocols for mice receiving WD and NCKD. Tumor volumes were assessed twice weekly, and mice were sacrificed when tumor volumes reached 1000mm3. Survival was calculated using a Log-rank test and tumor volumes were compared among dietary groups using Kruskal-Wallis test for significance. Results: Mice fed a NCKD demonstrated a trend towards decreased tumor volumes compared to mice fed WD and LF. Median tumor volume at study day 66 for mice fed WD, LF, and NCKD were 1091.2 mm3, 1082.9 mm3, and 661.5mm3 respectively. While the tumor volumes were smaller in mice fed NCKD versus LF or WD, these differences did not reach statistical significance (WD vs. NCKD, p=0.06; LF vs. NCKD, p=0.12). There was no significant difference between tumor volumes among mice fed WD compared to LF (p=0.95). Additionally, a trend towards improved survival was seen in mice fed NCKD vs. WD (p=0.09). Conclusion: This study in an immunocompetent xenograft model supports the findings of multiple previous studies. Mice fed a NCKD demonstrated a trend towards prolonged survival and decreased tumor volume compared to mice fed WD. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2877.

Background: Caloric restriction (CR) has been shown to be anti_cancer. However, whether these effects are the result of generalized reduction in overall caloric intake or reduced intake of macronutrients (i.e. carbohydrates) are unknown. We sought to investigate the differential effects of caloric and carbohydrate restriction upon prostate cancer tumor growth in a xenograft model. Materials and Methods: A total of 100 male SCID mice were injected subcutaneously with the LAPC-4 cell line. Mice were randomized to 1 of 4 diets: ad libitum Western diet (WD, 49% carbohydrates, 35% fat, and 16% protein), pair-fed No Carbohydrate Ketogenic Diet (NCKD; 1% carbohydrates, 83% fat, 16% protein), Western diet calorically restricted (WD-CR), and NCKD calorically restricted (NCKD-CR). Calorically restricted arms were fed 75% of the calories of their reference diet group. Tumor volumes and body weights were measured twice weekly. Mice were sacrificed when tumor volumes reached 1,000 mm3. Results: Relative to WD, there was a suggestion of smaller body weights in both NCKD-CR and WD-CR arms (rank-sum, p≤0.06). There was trend for heavier mice in the NCKD group (rank-sum, p=0.09). By day 50, median tumor volumes for NCKD, WD-CR, and NCKD-CR were 45, 51, and 62% smaller than WD (rank-sum, all p≤0.001). At any time point, there were no significant differences in tumor volume among the NCKD, NCKD-CR, and WD-CR arms. However, there was a suggestion of smaller tumors in the NCKD-CR arm by day 42 relative to NCKD and WD-CR (p Conclusions: Both CR and carbohydrate restriction without weight loss are effective in delaying tumor growth and improving mouse survival. We found no differences between caloric and carbohydrate restricted arms, though this may relate to loss of study power due to mouse infections. CR may further weaken the immune system of immunocompromised mice subjecting them to increased risk of infections. A confirmatory study is underway in a high-level barrier facility. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3243.

Introduction: Previous dietary studies indicate carbohydrate intake may influence prostate cancer biology, as LAPC-4 and LNCaP xenograft mice fed a no-carbohydrate ketogenic diet (NCKD; 84% fat-0% carbohydrate-16% protein kcal) had significantly smaller tumors and longer survival times compared to mice fed a Western diet (40% fat-44% carbohydrate-16% protein kcal). The NCKD mice were also found to have higher levels of circulating IGFBP-3 and the lowest levels of insulin, IGF-1, and IGF-1:IGFBP-3 ratio despite consuming more calories than the Western group. As it is nearly impossible for a human to consume and maintain a no-carbohydrate diet similar to that in the previous xenograft studies, we sought to determine whether diets containing 10% or 20% kcal from carbohydrates could slow tumor growth in a similar manner to the NCKD in a xenograft model. METHODS: A total of 150 male SCID mice were injected with LAPC-4 cells and placed on a Western diet (35% fat-49% carbohydrate-16% protein kcal) ad libitum. Two weeks post-injection, all mice were randomized to one of three arms: NCKD, 10% carbohydrate, or 20% carbohydrate. Ten mice not injected with tumor were fed an ad libitum low-fat diet (12% fat-72% carbohydrate-16% protein kcal) and served as the reference group in a modified-paired feeding protocol for the other three groups. Calorie intake and body weights were measured thrice weekly and tumor volumes twice per week. Mice were sacrificed when tumors reached 1,000mm3. RESULTS: Despite consuming 5-10% extra calories on average, all mice receiving low-carbohydrate diets were significantly lighter than the mice consuming the low-fat diet (p CONCLUSIONS: LAPC-4 xenograft mice fed a low-carbohydrate diet (10-20% carbohydrate kcal) had similar survival to mice consuming a NCKD (0% carbohydrate kcal). Thus, the survival benefit of a NCKD may be achievable with less restrictive low-carbohydrate diets. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2816.