The impact of diet and micronutrient supplements on the expression of neuroendocrine markers in murine Lady transgenic prostate

Lipid Metabolism and Epigenetics Crosstalk in Prostate Cancer

Prostate cancer (PCa) is the most commonly diagnosed malignant neoplasm in men in the Western world. Localized low-risk PCa has an excellent prognosis thanks to effective local treatments; however, despite the incorporation of new therapeutic strategies, metastatic PCa remains incurable mainly due to disease heterogeneity and the development of resistance to therapy. The mechanisms underlying PCa progression and therapy resistance are multiple and include metabolic reprogramming, especially in relation to lipid metabolism, as well as epigenetic remodelling, both of which enable cancer cells to adapt to dynamic changes in the tumour. Interestingly, metabolism and epigenetics are interconnected. Metabolism can regulate epigenetics through the direct influence of metabolites on epigenetic processes, while epigenetics can control metabolism by directly or indirectly regulating the expression of metabolic genes. Moreover, epidemiological studies suggest an association between a high-fat diet, which can alter the availability of metabolites, and PCa progression. Here, we review the alterations of lipid metabolism and epigenetics in PCa, before focusing on the mechanisms that connect them. We also discuss the influence of diet in this scenario. This information may help to identify prognostic and predictive biomarkers as well as targetable vulnerabilities.

Role of diet in prostate cancer: the epigenetic link

Diet is hypothesized to be a critical environmentally related risk factor for prostate cancer (PCa) development, and specific diets and dietary components can also affect PCa progression; however, the mechanisms underlying these associations remain elusive. As for a maturing organism, PCa's epigenome is plastic and evolves from the pre-neoplastic to the metastatic stage. In particular, epigenetic remodeling relies on substrates or cofactors obtained from the diet. Here we review the evidence that bridges dietary modulation to alterations in the prostate epigenome. We propose that such diet-related effects offer a mechanistic link between the impact of different diets and the course of PCa development and progression.

Capsaicin reduces the metastatic burden in the transgenic adenocarcinoma of the mouse prostate model

BACKGROUND

Capsaicin, the active compound in chili peppers, has demonstrated anti- carcinogenic properties in vitro in a number of malignancies, including the prostate. In the present study, we investigate the chemopreventive potential of capsaicin on prostate cancer using the transgenic adenocarcinoma of the mouse prostate (TRAMP) model. The TRAMP is a murine model that resembles the progression of human disease.

METHODS

Thirty-five 6-week-old TRAMP x C57BL/6 mice were randomized between treatment with capsaicin (5 mg/kg body weight) or control (saline) three times a week by oral gavage until 30 weeks of age. Body weight of animals was recorded thrice weekly. At termination, all tumors were extracted, recorded, and analyzed for histopathological analysis. To understand the effect of capsaicin on migration and invasion, in vitro experiments were carried out using PC3 cells.

RESULTS

Mice in the control group expressed an overall trend of higher-grade disease with 37.5% poorly differentiated (PD), 18.75% moderately differentiated (MD), and 44% of well-differentiated (WD) adenocarcinoma, compared to the capsaicin-treated group with only 27.7% PD, 61.0% of WD, and 11.1% of intraepithelial neoplasia (PIN). The treatment group demonstrated a higher incidence of noncancerous PIN lesions compared to the control group. The capsaicin group also demonstrated a significant reduction (P < 0.05) in the metastatic burden compared to the controls, which correlated to a reduction in p27(Kip) (1) expression and neuroendocrine differentiation in prostate tumors. Furthermore, there were no differences in body weight between groups overtime, and no pathological toxicities in the liver and gastrointestinal tract with capsaicin consumption. In vitro studies revealed a dose-dependent reduction in the invasion and migration capacity of PC3 cells.

CONCLUSION

The following study provides evidence supporting the safety and chemopreventive effects of capsaicin in the TRAMP model.

Mouse models of prostate cancer: picking the best model for the question

When the National Institutes of Health Mouse Models of Human Cancer Consortium initiated the Prostate Steering Committee 15 years ago, there were no genetically engineered mouse (GEM) models of prostate cancer (PCa). Today, a PubMed search for "prostate cancer mouse model" yields 3,200 publications and this list continues to grow. The first generation of GEM utilized the newly discovered and characterized probasin promoter driving viral oncogenes such as Simian virus 40 large T antigen to yield the LADY and TRAMP models. As the PCa research field has matured, the second generation of models has incorporated the single and multiple molecular changes observed in human disease, such as loss of PTEN and overexpression of Myc. Application of these models has revealed that mice are particularly resistant to developing invasive PCa, and once they achieve invasive disease, the PCa rarely resembles human disease. Nevertheless, these models and their application have provided vital information on human PCa progression. The aim of this review is to provide a brief primer on mouse and human prostate histology and pathology, provide descriptions of mouse models, as well as attempt to answer the age old question: Which GEM model of PCa is the best for my research question?

Nutritional and Functional Properties of Aqueous and Hydroalcoholic Extracts from Argentinean Propolis

Bee propolis is a natural product extensively used as an ingredient in functional foods in amounts that may confer health benefits. The aim of this study was to investigate the nutritional and functional properties (antioxidant activity) of aqueous and ethanolic extracts of propolis samples from Santiago del Estero province, northern Argentina. All propolis extracts contained macronutrients (glucose, fructose, sucrose and proteins), micronutrients (Na, K, Ca, P and Mg) and trace elements (Fe). Spectrophotometric, TLC and HPLC-DAD analyses showed the presence of several phenolic, flavonoid and non-flavonoid compounds, but in all cases the flavonoids prevailed. The PCA of polyphenolic content provided a clear separation of propolis in Group 1 (SE1, 2, 3, 4 and 7) and Group 2 (SE5 and 6) associated with phenolic compound content and collection regions. Two compounds, pinocembrin and chrysin, which could be used as chemical markers of Santiago del Estero propolis, were identified in all samples. Propolis samples extracted with water presented better radical scavenging ability than ethanolic extracts, independent of the antioxidant method (scavenging activity of ABTS•+, DPPH•, HO• and O2•- and β-carotene bleaching test). Such results correlated closely with the levels of total phenols and flavonoids in samples. The results justify the use of Argentine propolis as a functional dietary supplement.

Mineral and trace elements content in 30 accessions of tomato fruits (Solanum lycopersicum L.,) and wild relatives (Solanum pimpinellifolium L., Solanum cheesmaniae L. Riley, and Solanum habrochaites S. Knapp & D.M. Spooner)

Tomato quality and its potential health benefits are directly related to its chemical composition. The characterization of nutritional properties of Solanum germplasm is essential to choose suitable donor parents for breeding programs. In this sense, wild species could be very useful for tomato fruit quality genetic improvement. With this objective, in this work, we characterize micronutrients content in Eulycopersicon germplasm (20 cultivars of S. lycopersicum L. and 10 accessions of wild relatives) analyzing mineral (Na, K, Ca, Mg) and trace elements (Cu, Fe, Zn, Mn) and applying multidimensional analysis (principal component and cluster analysis). The classification obtained and the comparison of cultivars performance showed that wild accessions belonging to S. cheesmaniae (L. Riley), S. pimpinellifolium L., and S. habrochaites S. Knapp & D.M. Spooner can be of great usefulness in breeding programs to improve mineral content characteristics of conventional S. lycopersicum varieties due to its higher mineral content.