Dataset Information

The effect of carbohydrate restriction on prostate cancer tumor growth in a castrate mouse xenograft model.

ABSTRACT: No- and low-carbohydrate diets delay tumor growth compared to western diet (WD) in prostate cancer (PCa) xenograft studies. The effect of these diets in concert with androgen deprivation is unknown.A total of 160 male SCID mice were injected with 1× 10(5) LAPC-4 human PCa cells. Of these, 150 mice were castrated and randomized to an ad libitum WD or fed via a paired-feeding protocol with a no-carbohydrate ketogenic diet (NCKD), 10% carbohydrate diet, or 20% carbohydrate diet. The remaining 10 mice were not castrated and were fed an ad libitum WD. The mice were sacrificed once volumes reached 1,000?mm3 and survival tested using the log-rank test. Serum from the median surviving 8?mice/group was assayed for insulin, IGF-1, and IGFBP-3.Body weights were roughly equal among groups. The 10 non-castrated mice experienced accelerated tumor growth. Among castrated mice, WD had the most rapid tumor growth; 20% carbohydrate diet the slowest (P?=?0.046). Survival was not significantly different among the various carbohydrate restricted groups (P?=?0.51). When pooled, there was a non-significant trend (P?=?0.11) in improved survival among the carbohydrate restricted diets versus WD. No significant difference in serum insulin, IGF-1, and IGFBP-3 levels was noted among all groups at pre-randomization or at sacrifice.A 20% carbohydrate diet slowed tumor growth versus a WD. Though the benefit of carbohydrate restriction was somewhat less than in prior studies in non-castrate mice, these data still suggest diets achievable in humans may play a role in PCa management.

SUBMITTER: Caso J

PROVIDER: S-EPMC3594433 | biostudies-other | 2013 Apr

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

The effect of carbohydrate restriction on prostate cancer tumor growth in a castrate mouse xenograft model.

Caso Jorge J Masko Elizabeth M EM Ii Jean A Thomas JA Poulton Susan H SH Dewhirst Mark M Pizzo Salvatore V SV Freedland Stephen J SJ

The Prostate 20121004 5

<h4>Background</h4>No- and low-carbohydrate diets delay tumor growth compared to western diet (WD) in prostate cancer (PCa) xenograft studies. The effect of these diets in concert with androgen deprivation is unknown.<h4>Methods</h4>A total of 160 male SCID mice were injected with 1× 10(5) LAPC-4 human PCa cells. Of these, 150 mice were castrated and randomized to an ad libitum WD or fed via a paired-feeding protocol with a no-carbohydrate ketogenic diet (NCKD), 10% carbohydrate diet, or 20% car ...[more]

PMID: 23038057

Similar Datasets

Project description:BackgroundPreviously, we showed that carbohydrate restriction with calorie restriction slowed tumor growth in xenograft mouse prostate cancer models. Herein, we examined the impact of carbohydrate restriction without calorie restriction on tumor development within the context of diet-induced obesity in the Hi-Myc transgenic mouse model of prostate cancer.MethodsMice were randomized at 5 weeks of age to ad libitum western diet (WD; 40% fat, 42% carbohydrate; n=39) or ad libitum no carbohydrate ketogenic diet (NCKD; 82% fat, 1% carbohydrate; n=44). At age 3 or 6 months, mice were killed, prostates weighed and prostate histology, proliferation, apoptosis and macrophage infiltration evaluated by hematoxylin and eosin, Ki67, TUNEL and F4/80 staining, respectively. Body composition was assessed by DEXA, serum cytokines measured using multiplex, and Akt/mTOR signaling assessed by Western.ResultsCaloric intake was higher in the NCKD group, resulting in elevated body weights at 6 months of age, relative to the WD group (45 g vs 38g; P=0.008). Despite elevated body weights, serum monocyte chemoattractant protein (MCP)-1 and interleukin (IL)-1α levels were lower in NCKD versus WD mice (P=0.046 and P=0.118, respectively), and macrophage infiltration was reduced in prostates of NCKD versus WD mice (P=0.028). Relative Akt phosphorylation and phospho-S6 ribosomal protein levels were reduced in prostates of NCKD versus WD mice. However, while mice randomized to NCKD had smaller prostates after adjustment for body weight at 3 and 6 months (P=0.004 and P=0.002, respectively), NCKD mice had higher rates of adenocarcinoma at 6 months compared to WD mice (100 vs 80%, P=0.04).ConclusionsDespite higher caloric intake and elevated body weights, carbohydrate restriction lowered serum MCP-1 levels, reduced prostate macrophage infiltration, reduced prostate weight, but failed to slow adenocarcinoma development. Together, these data suggest that although carbohydrate restriction within the context of obesity may reduce obesity-associated systemic inflammation and perhaps slow tumor growth, it is not sufficient to counteract obesity-associated tumor development.

Project description:Copper is an element required for cell proliferation and angiogenesis. Human prostate cancer xenografts with increased (64)Cu radioactivity were visualized previously by PET using (64)CuCl2 as a radiotracer ((64)CuCl2 PET). This study aimed to determine whether the increased tumor (64)Cu radioactivity was due to increased cellular uptake of (64)Cu mediated by human copper transporter 1 (hCtr1) or simply due to nonspecific binding of ionic (64)CuCl2 to tumor tissue. In addition, the functional role of hCtr1 in proliferation of prostate cancer cells and tumor growth was also assessed.A lentiviral vector encoding short-hairpin RNA specific for hCtr1 (Lenti-hCtr1-shRNA) was constructed for RNA interference-mediated knockdown of hCtr1 expression in prostate cancer cells. The degree of hCtr1 knockdown was determined by Western blot, and the effect of hCtr1 knockdown on copper uptake and proliferation were examined in vitro by cellular (64)Cu uptake and cell proliferation assays. The effects of hCtr1 knockdown on tumor uptake of (64)Cu were determined by PET quantification and tissue radioactivity assay. The effects of hCtr1 knockdown on tumor growth were assessed by PET/CT and tumor size measurement with a caliper.RNA interference-mediated knockdown of hCtr1 was associated with the reduced cellular uptake of (64)Cu and the suppression of prostate cancer cell proliferation in vitro. At 24 h after intravenous injection of the tracer (64)CuCl2, the (64)Cu uptake by the tumors with knockdown of hCtr1 (4.02 ± 0.31 percentage injected dose per gram [%ID/g] in Lenti-hCtr1-shRNA-PC-3 and 2.30 ± 0.59 %ID/g in Lenti-hCtr1-shRNA-DU-145) was significantly lower than the (64)Cu uptake by the control tumors without knockdown of hCtr1 (7.21 ± 1.48 %ID/g in Lenti-SCR-shRNA-PC-3 and 5.57 ± 1.20 %ID/g in Lenti-SCR-shRNA-DU-145, P < 0.001) by PET quantification. Moreover, the volumes of prostate cancer xenograft tumors with knockdown of hCtr1 (179 ± 111 mm(3) for Lenti-hCtr1-shRNA-PC-3 or 39 ± 22 mm(3) for Lenti-hCtr1-shRNA-DU-145) were significantly smaller than those without knockdown of hCtr1 (536 ± 191 mm(3) for Lenti- SCR-shRNA-PC-3 or 208 ± 104 mm(3) for Lenti-SCR-shRNA-DU-145, P < 0.01).Overall, data indicated that hCtr1 is a promising theranostic target, which can be further developed for metabolic imaging of prostate cancer using (64)CuCl2 PET/CT and personalized cancer therapy targeting copper metabolism.

Project description:BackgroundM2-like macrophages are associated with the pathogenesis of castrate-resistant prostate cancer (CRPC). We sought to determine if dietary omega-3 fatty acids (ω-3 FAs) delay the development and progression of CRPC and inhibit tumor-associated M2-like macrophages.MethodsMycCap cells were grown subcutaneously in immunocompetent FVB mice. Mice were castrated when tumors reached 300 mm2. To study effects of dietary ω-3 FAs on development of CRPC, ω-3 or ω-6 diets were started 2 days after castration and mice sacrificed after early regrowth of tumors. To study ω-3 FA effects on progression of CRPC, tumors were allowed to regrow after castration before starting the diets. M2 (CD206+) macrophages were isolated from allografts to examine ω-3 FA effects on macrophage function. Omega-3 fatty acid effects on androgen-deprived RAW264.7 M2 macrophages were studied by RT-qPCR and a migration/ invasion assay.ResultsThe ω-3 diet combined with castration lead to greater MycCap tumor regression (tumor volume reduction: 182.2 ± 33.6 mm3) than the ω-6 diet (tumor volume reduction: 148.3 ± 35.2; p = 0.003) and significantly delayed the time to CRPC (p = 0.006). Likewise, the ω-3 diet significantly delayed progression of established castrate-resistant MycCaP tumors (p = 0.003). The ω-3 diet (as compared to the ω-6 diet) significantly reduced tumor-associated M2-like macrophage expression of CSF-1R in the CRPC development model, and matrix metallopeptidase-9 (MMP-9) and vascular endothelial growth factor (VEGF) in the CRPC progression model. Migration of androgen-depleted RAW264.7 M2 macrophages towards MycCaP cells was reversed by addition of docosahexaenoic acid (ω-3).ConclusionsDietary omega-3 FAs (as compared to omega-6 FAs) decreased the development and progression of CRPC in an immunocompetent mouse model, and had inhibitory effects on M2-like macrophage function. Clinical trials are warranted evaluating if a fish oil-based diet can delay the time to castration resistance in men on androgen deprivation therapy, whereas further preclinical studies are warranted evaluating fish oil for more advanced CRPC.

Dataset Information

The effect of carbohydrate restriction on prostate cancer tumor growth in a castrate mouse xenograft model.

Publications

The effect of carbohydrate restriction on prostate cancer tumor growth in a castrate mouse xenograft model.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets