Generation of an epigenetic signature by chronic hypoxia in prostate cells

Increasing levels of tissue hypoxia have been reported as a natural feature of the aging prostate gland and may be a risk factor for the development of prostate cancer. In this study, we have used PwR-1E benign prostate epithelial cells and an equivalently aged hypoxia-adapted PwR-1E sub-line to identify phenotypic and epigenetic consequences of chronic hypoxia in prostate cells. We have identified a significantly altered cellular phenotype in response to chronic hypoxia as characterized by increased receptor-mediated apoptotic resistance, the induction of cellular senescence, increased invasion and the increased secretion of IL-1 beta, IL6, IL8 and TNFalpha cytokines. In association with these phenotypic changes and the absence of HIF-1 alpha protein expression, we have demonstrated significant increases in global levels of DNA methylation and H3K9 histone acetylation in these cells, concomitant with the increased expression of DNA methyltransferase DMNT3b and gene-specific changes in DNA methylation at key imprinting loci. In conclusion, we have demonstrated a genome-wide adjustment of DNA methylation and histone acetylation under chronic hypoxic conditions in the prostate. These epigenetic signatures may represent an additional mechanism to promote and maintain a hypoxic-adapted cellular phenotype with a potential role in tumour development.

Laser ablation-based one-step generation and bio-functionalization of gold nanoparticles conjugated with aptamers

Background: Bio-conjugated nanoparticles are important analytical tools with emerging biological and medical applications. In this context, in situ conjugation of nanoparticles with biomolecules via laser ablation in an aqueous media is a highly promising one-step method for the production of functional nanoparticles resulting in highly efficient conjugation. Increased yields are required, particularly considering the conjugation of cost-intensive biomolecules like RNA aptamers. Results: Using a DNA aptamer directed against streptavidin, in situ conjugation results in nanoparticles with diameters of approximately 9 nm exhibiting a high aptamer surface density (98 aptamers per nanoparticle) and a maximal conjugation efficiency of 40.3%. We have demonstrated the functionality of the aptamer-conjugated nanoparticles using three independent analytical methods, including an agglomeration-based colorimetric assay, and solid-phase assays proving high aptamer activity. To demonstrate the general applicability of the in situ conjugation of gold nanoparticles with aptamers, we have transferred the method to an RNA aptamer directed against prostate-specific membrane antigen (PSMA). Successful detection of PSMA in human prostate cancer tissue was achieved utilizing tissue microarrays. Conclusions: In comparison to the conventional generation of bio-conjugated gold nanoparticles using chemical synthesis and subsequent bio-functionalization, the laser-ablation-based in situ conjugation is a rapid, one-step production method. Due to high conjugation efficiency and productivity, in situ conjugation can be easily used for high throughput generation of gold nanoparticles conjugated with valuable biomolecules like aptamers.

Factors influencing Nigerian men's decision to undergo prostate specific antigen testing.

Background: Prostate cancer is a major cause of cancer death in Nigerian men. Attempts to reduce mortality from prostate cancer have focused mainly on early detection of the disease by the use of PSA testing. As a result of the increased incidence of prostate cancer in Nigeria despite the widespread availability of testing facilities, it became pertinent to understand the salient factors that prompt Nigerian men to go for prostate cancer testing. Objective: This study explores the factors that influence a group of Nigerian men’s decision to go for Prostate Specific Antigen (PSA) testing. Methods: Following ethical approval, semi structured interviews were conducted with a group of 10 men who had PSA test following consultation with their doctor with signs and symptoms at the University of Benin Teaching Hospital from July to August, 2010. Interview transcripts were analysed by employing steps proposed by Collaizi (1978). Results: Five themes were identified: the symptoms experienced, the influence of friends and relatives, older age associated with increased awareness, accessibility to testing services and the knowledge of the PSA test. Conclusion: The study revealed that there continues to be a considerable lack of awareness and knowledge about prostate cancer and screening.

Effects of radiation therapy on the structure and function of the pelvic floor muscles of patients with cancer in the pelvic area : a systematic review

Purpose Radiation therapy (RT) is often recommended in the treatment of pelvic cancers. Following RT, a high prevalence of pelvic floor dysfunctions (urinary incontinence, dyspareunia, and fecal incontinence) is reported. However, changes in pelvic floor muscles (PFMs) after RT remain unclear. The purpose of this review was to systematically document the effects of RT on the PFM structure and function in patients with cancer in the pelvic area. Methods An electronic literature search using Pubmed Central, CINAHL, Embase, and SCOPUS was performed from date of inception up to June 2014. The following keywords were used: radiotherapy, muscle tissue, and pelvic floor. Two reviewers selected the studies in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement (PRISMA). Out of the 369 articles screened, 13 met all eligibility criteria. The methodological quality was assessed using the QualSyst scoring system, and standardized mean differences were calculated. Results Thirteen studies fulfilled all inclusion criteria, from which four were of good methodological quality. One presented strong evidence that RT affects PFM structure in men treated for prostate cancer. Four presented high-level evidence that RT affects PFM function in patients treated for rectal cancer. Meta-analysis was not possible due to heterogeneity and lack of descriptive statistics. Conclusion There is some evidence that RT has detrimental impacts on both PFMs’ structure and function. Implications for cancer survivors A better understanding of muscle damage and dysfunction following RT treatment will improve pelvic floor rehabilitation and, potentially, prevention of its detrimental impacts.

Public health implications of dietary fiber intake to reduce the cost of chronic diseases

Objective: To assess the epidemiological evidence on dietary fiber intake and chronic diseases and make public health recommendations for the population in Romania based on their consumption. Populations that consume more dietary fiber from cereals, fruits and vegetables have less chronic disease. Dietary Reference Intakes recommend consumption of 14 g dietary fiber per 1,000 kcal, or 25 g for adult women and 38 g for adult men, based on epidemiologic studies showing protection against cardiovascular disease, stroke, hypertension, diabetes, obesity, metabolic syndrome, gastrointestinal disorders, colorectal -, breast -, gastric -, endometrial -, ovarian - and prostate cancer. Furthermore, increased consumption of dietary fiber improves serum lipid concentrations, lowers blood pressure, blood glucose leads to low glycemic index, aids in weight loss, improve immune function, reduce inflammatory marker levels, reduce indicators of inflammation. Dietary fibers contain an unique blend of bioactive components including resistant starches, vitamins, minerals, phytochemicals and antioxidants. Dietary fiber components have important physiological effects on glucose, lipid, protein metabolism and mineral bioavailability needed to prevent chronic diseases. Materials and methods: Data regarding diet was collected based on questionnaires. We used mathematical formulas to calculate the mean dietary fiber intake of Romanian adult population and compared the results with international public health recommendations. Results: Based on the intakes of vegetables, fruits and whole cereals we calculated the Mean Dietary Fiber Intake/day/person (MDFI). Our research shows that the national average MDFI was 9.8 g fiber/day/person, meaning 38% of Dietary Requirements, and the rest of 62% representing a “fiber gap” that we have to take into account. This deficiency predisposes to chronic diseases. Conclusions and recommendations:The poor control of relationship between dietary fiber intake and chronic diseases is a major issue that can result in adverse clinical and economic outcomes. The population in Romania is at risk to develop such diseases due to the deficient fiber consumption. A model of chronic diseases costs is needed to aid attempts to reduce them while permitting optimal management of the chronic diseases. This paper presents a discussion of the burden of chronical disease and its socio-economic implications and proposes a model to predict the costs reduction by adequate intake of dietary fiber.

Effects of radiation therapy on the structure and function of the pelvic floor muscles of patients with cancer in the pelvic area : a systematic review

Purpose Radiation therapy (RT) is often recommended in the treatment of pelvic cancers. Following RT, a high prevalence of pelvic floor dysfunctions (urinary incontinence, dyspareunia, and fecal incontinence) is reported. However, changes in pelvic floor muscles (PFMs) after RT remain unclear. The purpose of this review was to systematically document the effects of RT on the PFM structure and function in patients with cancer in the pelvic area. Methods An electronic literature search using Pubmed Central, CINAHL, Embase, and SCOPUS was performed from date of inception up to June 2014. The following keywords were used: radiotherapy, muscle tissue, and pelvic floor. Two reviewers selected the studies in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement (PRISMA). Out of the 369 articles screened, 13 met all eligibility criteria. The methodological quality was assessed using the QualSyst scoring system, and standardized mean differences were calculated. Results Thirteen studies fulfilled all inclusion criteria, from which four were of good methodological quality. One presented strong evidence that RT affects PFM structure in men treated for prostate cancer. Four presented high-level evidence that RT affects PFM function in patients treated for rectal cancer. Meta-analysis was not possible due to heterogeneity and lack of descriptive statistics. Conclusion There is some evidence that RT has detrimental impacts on both PFMs’ structure and function. Implications for cancer survivors A better understanding of muscle damage and dysfunction following RT treatment will improve pelvic floor rehabilitation and, potentially, prevention of its detrimental impacts.

Revisión sistemática utilidad de asa y calcio con o sin vitamina d en la prevención de cáncer colorrectal y la recurrencia de pólipos adenomatosos en paciente con riesgo de padecer esta patología

Introducción: El cáncer colorrectal es una patología con alto impacto en la salud pública, debido a su prevalencia, incidencia, severidad, costo e impacto en la salud mental y física del individuo y la familia. Ensayos clínicos realizados en pacientes con antecedente de infarto al miocardio que consumían ácido acetil salicílico (asa), calcio con y sin vitamina D, mostraron asociación entre el consumo de estos medicamentos y disminución en la incidencia en cáncer colorrectal y pólipos adenomatosos. Objetivo: Evaluar la literatura sobre el uso de asa, calcio con y sin vitamina D con relación a su impacto en la prevención del cáncer colorrectal y pólipos adenomatosos. Métodos: Se realizó revisión sistemática buscando ensayos clínicos realizados en pacientes con factores de riesgo para cáncer colorrectal y pólipos adenomatosos que usaron asa, calcio con y sin vitamina D fueron incluidos. Resultados: se escogieron 105 para la revisión sistemática. Conclusiones: Es necesario desarrollar más estudios que lleven a evaluar el efecto protector de la aspirina, calcio y vitamina D. En los artículos revisados la aspirina a dosis de 81 a 325 mg día se correlaciona con reducción de riesgo de aparición de CRC aunque la dosis ideal, el tiempo de inicio y la duración de la ingesta continua no son claros. Hacen falta estudios que comparen poblaciones con ingesta de asa a diferentes dosis.

Identificazione di un nuovo meccanismo microRNA-dipendente di resistenza all'inibizione della via di segnale PI3K/AKT nel carcinoma della prostata

Benché le alterazioni della via PI3K/AKT siano molto sudiate a causa del loro ruolo nella tumorigenesi, e rappresentino pertanto un importante bersaglio terapeutico, i risultati di numerosi studi clinici con inibitori di PI3K o AKT sono finora deludenti, in parte a causa dell’insorgenza di resistenza provocata dall'interruzione dei circuiti di feedback negativo. In questo studio, abbiamo scoperto che l’inattivazione farmacologica di AKT in cellule di carcinoma prostatico PC3 porta alla down-regolazione di un microRNA con funzione di oncosoppressore, il miR-145-5p, e ad un drammatico aumento di espressione di uno dei suoi geni target, cioè N/KRas. E’ interessante sottolineare che questo microRNA è considerato un marker di progressione metastatica nel carcinoma prostatico, il cui livello di espressione aiuta a discriminare tra pazienti con iperplasia prostatica benigna e cancro alla prostata. Inoltre, la bassa espressione di miR-145 aumenta il rischio di progressione della malattia da localizzata a metastatica. La conferma che l’aumento di Ras, osservato sia in termini di mRNA che di proteina, è dipendente dalla caduta del miR-145-5p, è stata poi ottenuta tramite un modello di PC3 ingegnerizzate per ottenere il silenziamento inducibile del miR-145-5p. Tramite un array di fosfoproteine siamo poi stati in grado di verificare che l’aumento di Ras provoca la riattivazione della cascata di PI3K/AKT e di ERK. Dal punto di vista meccanicistico, quindi, lo studio ha portato all’identificazione di un nuovo meccanismo di resistenza adattativa, in cui l’inattivazione di AKT provoca una caduta del miR-145-5p che, a sua volta, aumenta l’espressione di Ras e riattiva il signaling di PI3K, rendendo inefficace il trattamento farmacologico. Questi risultati sono particolarmente rilevanti alla luce di recenti studi (NCT04493853; NCT03072238; NCT02525068) e di trial clinici in corso (NCT04737109; NCT03673787), basati sulla somministrazione combinata di inibitori della sintesi degli androgeni con gli inibitori di AKT capitasertib o ipatasertib.

Antitumor Activity Of Irradiated Riboflavin On Human Renal Carcinoma Cell Line 786-o.

Riboflavin (vitamin B2) is a precursor for coenzymes involved in energy production, biosynthesis, detoxification, and electron scavenging. Previously, we demonstrated that irradiated riboflavin (IR) has potential antitumoral effects against human leukemia cells (HL60), human prostate cancer cells (PC3), and mouse melanoma cells (B16F10) through a common mechanism that leads to apoptosis. Hence, we here investigated the effect of IR on 786-O cells, a known model cell line for clear cell renal cell carcinoma (CCRCC), which is characterized by high-risk metastasis and chemotherapy resistance. IR also induced cell death in 786-O cells by apoptosis, which was not prevented by antioxidant agents. IR treatment was characterized by downregulation of Fas ligand (TNF superfamily, member 6)/Fas (TNF receptor superfamily member 6) (FasL/Fas) and tumor necrosis factor receptor superfamily, member 1a (TNFR1)/TNFRSF1A-associated via death domain (TRADD)/TNF receptor-associated factor 2 (TRAF) signaling pathways (the extrinsic apoptosis pathway), while the intrinsic apoptotic pathway was upregulated, as observed by an elevated Bcl-2 associated x protein/B-cell CLL/lymphoma 2 (Bax/Bcl-2) ratio, reduced cellular inhibitor of apoptosis 1 (c-IAP1) expression, and increased expression of apoptosis-inducing factor (AIF). The observed cell death was caspase-dependent as proven by caspase 3 activation and poly(ADP-ribose) polymerase-1 (PARP) cleavage. IR-induced cell death was also associated with downregulation of v-src sarcoma (Schmidt-Ruppin A-2) viral oncogene homologue (avian)/protein serine/threonine kinase B/extracellular signal-regulated protein kinase 1/2 (Src/AKT/ERK1/2) pathway and activation of p38 MAP kinase (p38) and Jun-amino-terminal kinase (JNK). Interestingly, IR treatment leads to inhibition of matrix metalloproteinase-2 (MMP-2) activity and reduced expression of renal cancer aggressiveness markers caveolin-1, low molecular weight phosphotyrosine protein phosphatase (LMWPTP), and kinase insert domain receptor (a type III receptor tyrosine kinase) (VEGFR-2). Together, these results show the potential of IR for treating cancer.

Fatores associados à realização dos exames de rastreamento para o câncer de próstata: um estudo de base populacional

O objetivo deste estudo foi analisar a prevalência da realização dos exames de rastreamento para o câncer de próstata em homens com 50 anos ou mais de idade, segundo variáveis socioeconômicas, demográficas, de comportamentos relacionados à saúde e presença de morbidade. O estudo foi do tipo transversal, de base populacional, e as análises estatísticas consideraram o delineamento da amostra. Os fatores associados à não realização dos exames de rastreamento do câncer de próstata, foram: ter de idade menor que 70 anos, ter escolaridade de até 8 anos, renda familiar per capita menor que 0,5 salário mínimo, não ter diabetes, ter limitação visual e não ter ido ao dentista no último ano. O SUS foi responsável pela realização de 41% dos exames de rastreamento do câncer de próstata referidos. Este estudo apontou que apesar da controvérsia sobre e efetividade do toque retal e da dosagem do Antígeno Específico Prostático (PSA) para a detecção do câncer de próstata, parcela significativa da população masculina vem realizando estes exames para os quais existem significativas desigualdades socioeconômicas quanto ao acesso.

Evaluation of Antiproliferative, Anti-Type 2 Diabetes, and Antihypertension Potentials of Ellagitannins from Strawberries (Fragaria x ananassa Duch.) Using In Vitro Models

Strawberries represent the main source of ellagic acid derivatives in the Brazilian diet, corresponding to more than 50% of all phenolic compounds found in the fruit. There is a particular interest in the determination of the ellagic acid content in fruits because of possible chemopreventive benefits. In the present study, the potential health benefits of purified ellagitannins from strawberries were evaluated in relation to the antiproliferative activity and in vitro inhibition of alpha-amylase, alpha-glucosidase, and angiotensin I-converting enzyme (ACE) relevant for potential management of hyperglycemia and hypertension. Therefore, a comparison among ellagic acid, purified ellagitannins, and a strawberry extract was done to evaluate the possible synergistic effects of phenolics. In relation to the antiproliferative activity, it was observed that ellagic acid had the highest percentage inhibition of cell proliferation. The strawberry extract had lower efficacy in inhibiting the cell proliferation, indicating that in the case of this fruit there is no synergism. Purified ellagitannins had high alpha-amylase and ACE inhibitory activities. However, these compounds had low alpha-glucosidase inhibitory activity. These results suggested that the ellagitannins and ellagic acid have good potential for the management of hyperglycemia and hypertension linked to type 2 diabetes. However, further studies with animal and human models are needed to advance the in vitro assay-based biochemical rationale from this study.

Determination of the Most Efficient Temperature for Radiofrequency Ablation of Renal Cells: A Prospective Study in Dogs

Background and Purpose: Radiofrequency (RF) ablation of renal tumors is a major technique for tumor cell destruction while preserving healthy renal parenchyma. There is no consensus in the literature regarding the optimal temperature, impedance, and time for RF application for effective cell destruction. This study investigated two variables while keeping time unchanged: Temperature for RF cell destruction and tissue impedance in dog kidneys. Materials and Methods: Sixteen dogs had renal punctures through videolaparoscopy for RF interstitial tissue ablation. A RF generator was applied for 10 minutes to the dog's kidney at different target temperatures: 80 degrees C, 90 degrees C, and 100 degrees C. On postoperative day14, the animals were sacrificed and nephrectomized. All lesions were macroscopically and microscopically examined. The bioelectrical impedance was evaluated at three different temperatures. Results: Renal injuries were wider and deeper at 90 degrees C (P < 0.001), and they were similar at 80 degrees C and 100 degrees C. The bioelectrical impedance was lower at 90 degrees C than at the temperatures of 80 degrees C and 100 degrees C (P < 0.001). Viable cells in the RF ablation tissue area were not found in the microscopic examination. Conclusion: The most effective cell destruction in terms of width and depth was achieved at 90 degrees C, which was also the optimal temperature for tissue impedance. RF ablation of renal cells eliminated all viable cells.

Epigenetic Silencing of CRABP2 and MX1 in Head and Neck Tumors

Head and neck squamous cell carcinoma (HNSCC) is a heterogeneous disease affecting the epithelium of the oral cavity, pharynx and larynx. Conditions of most patients are diagnosed at late stages of the disease, and no sensitive and specific predictors of aggressive behavior have been identified yet. Therefore, early detection and prognostic biomarkers are highly desirable for a more rational management of the disease. Hypermethylation of CpG islands is one of the most important epigenetic mechanisms that leads to gene silencing in tumors and has been extensively used for the identification of biomarkers. In this study, we combined rapid subtractive hybridization and microarray analysis in a hierarchical manner to select genes that are putatively reactivated by the demethylating agent 5-aza-2'-deoxycytidine (5Aza-dC) in HNSCC cell lines (FaDu, UM-SCC-14A, UM-SCC-17A, UM-SCC-38A). This combined analysis identified 78 genes, 35 of which were reactivated in at least 2 cell lines and harbored a CpG island at their 5' region. Reactivation of 3 of these 35 genes (CRABP2, MX1, and SLC15A3) was confirmed by quantitative real-time polymerase chain reaction (PCR; fold change, >= 3). Bisulfite sequencing of their CpG islands revealed that they are indeed differentially methylated in the HNSCC cell lines. Using methylation-specific PCR, we detected a higher frequency of CRABP2 (58.1% for region 1) and MX1 (46.3%) hypermethylation in primary HNSCC when compared with lymphocytes from healthy individuals. Finally, absence of the CRABP2 protein was associated with decreased disease-free survival rates, supporting a potential use of CRABP2 expression as a prognostic biomarker for HNSCC patients.

Associations between glutathione peroxidase-1 Pro198Leu polymorphism, selenium status, and DNA damage levels in obese women after consumption of Brazil nuts

Objective: Alterations in selenium (Se) status may result in suboptimal amounts of selenoproteins, which have been associated with increased oxidative stress levels. The Pro198Leu polymorphism at the glutathione peroxidase-1 (GPx1) gene is supposed to be functional. The response of Se status, GPx activity, and levels of DNA damage to a Se supplementation trial between the genotypes related to that polymorphism was investigated. Methods: A randomized trial was conducted with 37 morbidly obese women. Participants consumed one Brazil nut, which provided approximately 290 mu g of Se a day, for 8 wk. Blood Se concentrations, erythrocyte GPx activity, and DNA damage levels were measured at baseline and at 8 wk. The results were compared by genotypes. Results: The genotype frequencies were 0.487, 0.378, and 0.135 for Pro/Pro (the wild-type genotype), Pro/Leu, and Leu/Leu, respectively. At baseline, 100% of the subjects were Se deficient, and after the supplementation, there was an improvement in plasma Se (P < 0.001 for Pro/Pro and Pro/Leu, P < 0.05 for Leu/Leu), erythrocyte Se (P = 0.00 for Pro/Pro and Pro/Leu, P < 0.05 for Leu/Leu), and GPx activity (P = 0.00 for Pro/Pro, P < 0.00001 for Pro/Leu, P < 0.001 for Leu/Leu). In addition, the Pro/Pro group showed a decrease in DNA damage after Brazil nut consumption compared with baseline (P < 0.005), and those levels were higher in Leu/Leu subjects compared with those with the wild-type genotype (P < 0.05). Conclusion: Consumption of one unit of Brazil nuts daily effectively increases Se status and increases GPx activity in obese women, regardless of GPx1 Pro198Leu polymorphism. However, the evaluated biomarkers showed distinct results in response to the supplementation when the polymorphism was considered. (c) 2011 Elsevier Inc. All rights reserved.

Bixin and lycopene modulation of free radical generation induced by cisplatin-DNA interaction

This work evaluated the Modulation of reactive oxygen species (ROS) produced by the cisplatin-human DNA interaction in a cell-free experimental model by the carotenoids bixin and lycopene extracted from, natural dietary Sources and purified through luminol- and Cypridina luciferin methoxy-analogue (MCLA)- enhanced chemiluminescence assays. The results showed that the ROS generation by DNA-cisplatin interaction was inhibited by both lycopene and bixin in a concentration-dependent manner. At a concentration of 100 mu M, lycopene and bixin inhibited Superoxide anion (O center dot(2)) generation at 90% and 82%, respectively, and the total ROS generation at 44% and 42%, respectively. The formation of significant amounts of isomers or degradation products of both carotenoids was not observed after ROS scavenging, as evaluated by high-performance liquid chromatography. Taken together, these results Suggest that carotenoids can be helpful to Modulate the oxidative stress found in cancer therapy with cisplatin. (c) 2008 Elsevier Ltd. All rights reserved.