998 resultados para Prostate body
Resumo:
Molecular characterization of radical prostatectomy specimens after systemic therapy may identify a gene expression profile for resistance to therapy. This study assessed tumor cells from patients with prostate cancer participating in a phase II neoadjuvant docetaxel and androgen deprivation trial to identify mediators of resistance. Transcriptional level of 93 genes from a docetaxel-resistant prostate cancer cell lines microarray study was analyzed by TaqMan low-density arrays in tumors from patients with high-risk localized prostate cancer (36 surgically treated, 28 with neoadjuvant docetaxel þ androgen deprivation). Gene expression was compared between groups and correlated with clinical outcome. VIM, AR and RELA were validated by immunohistochemistry. CD44 and ZEB1 expression was tested by immunofluorescence in cells and tumor samples. Parental and docetaxel-resistant castration-resistant prostate cancer cell lines were tested for epithelial-to-mesenchymal transition (EMT) markers before and after docetaxel exposure. Reversion of EMT phenotype was investigated as a docetaxel resistance reversion strategy. Expression of 63 (67.7%) genes differed between groups (P < 0.05), including genes related to androgen receptor, NF-k B transcription factor, and EMT. Increased expression of EMT markers correlated with radiologic relapse. Docetaxel-resistant cells had increased EMT and stem-like cell markers expression. ZEB1 siRNA transfection reverted docetaxel resistance and reduced CD44 expression in DU-145R and PC-3R. Before docetaxel exposure, a selected CD44 þ subpopulation of PC-3 cells exhibited EMT phenotype and intrinsic docetaxel resistance; ZEB1/CD44 þ subpopulations were found in tumor cell lines and primary tumors; this correlated with aggressive clinical behavior. This study identifies genes potentially related to chemotherapy resistance and supports evi-dence of the EMT role in docetaxel resistance and adverse clinical behavior in early prostate cancer.
Resumo:
We compute families of symmetric periodic horseshoe orbits in the restricted three-body problem. Both the planar and three-dimensional cases are considered and several families are found.We describe how these families are organized as well as the behavior along and among the families of parameters such as the Jacobi constant or the eccentricity. We also determine the stability properties of individual orbits along the families. Interestingly, we find stable horseshoe-shaped orbit up to the quite high inclination of 17◦
Resumo:
Background: Endocannabinoids and temperament traits have been linked to both physical activity and body mass index (BMI) however no study has explored how these factors interact in females. The aims of this cross-sectional study were to 1) examine differences among distinct BMI groups on daytime physical activity and time spent in moderate-vigorous physical activity (MVPA), temperament traits and plasma endocannabinoid concentrations; and 2) explore the association and interaction between MVPA, temperament, endocannabinoids and BMI. Methods: Physical activity was measured with the wrist-worn accelerometer Actiwatch AW7, in a sample of 189 female participants (43 morbid obese, 30 obese, and 116 healthy-weight controls). The Temperament and Character Inventory-Revised questionnaire was used to assess personality traits. BMI was calculated by bioelectrical impedance analysis via the TANITA digital scale. Blood analyses were conducted to measure levels of endocannabinoids and endocannabinoid-related compounds. Path-analysis was performed to examine the association between predictive variables and MVPA. Results: Obese groups showed lower MVPA and dysfunctional temperament traits compared to healthy-weight controls. Plasma concentrations of 2-arachidonoylglyceryl (2-AG) were greater in obese groups. Path-analysis identified a direct effect between greater MVPA and low BMI (b = −0.13, p = .039) and high MVPA levels were associated with elevated anandamide (AEA) levels (b = 0.16, p = .049) and N-oleylethanolamide (OEA) levels (b = 0.22, p = .004), as well as high Novelty seeking (b = 0.18, p<.001) and low Harm avoidance (b = −0.16, p<.001). Conclusions: Obese individuals showed a distinct temperament profile and circulating endocannabinoids compared to controls. Temperament and endocannabinoids may act as moderators of the low MVPA in obesity.
Resumo:
We study the relative equilibria of the limit case of the pla- nar Newtonian 4{body problem when three masses tend to zero, the so-called (1 + 3){body problem. Depending on the values of the in- nitesimal masses the number of relative equilibria varies from ten to fourteen. Always six of these relative equilibria are convex and the oth- ers are concave. Each convex relative equilibrium of the (1 + 3){body problem can be continued to a unique family of relative equilibria of the general 4{body problem when three of the masses are su ciently small and every convex relative equilibrium for these masses belongs to one of these six families.
Resumo:
Prostate cancer is generally a slowly developing disease. However, some cancers develop into an aggressive, metastasic and consequently life-threatening state. The mechanisms of prostate cancer spread are still mainly unidentified but hormones and growth factors are known to been involved. The forming of new blood vessels i.e. angiogenesis is crucial for tumor growth. Blood vessels and lymphatic vessels are also prominent routes for metastasis. Both angiogenic and lymphangiogenic factors are overexpressed in prostate cancer. We established an in vivo model to study the factors effecting human prostate cancer growth and metastasis. Tumors were produced by the orthotopic inoculation of PC-3 prostate cancer cells into the prostates of immunodeficient mice. Like human prostate tumors, these tumors metastasized to prostate-draining lymph nodes. Treatment of the mice with the bisphosphonate alendronate known to decrease prostate cancer cell invasion in vitro inhibited metastasis and decreased tumor growth. Decreased tumor growth was associated with decreased angiogenesis and increased apoptosis of tumor cells. To elucidate the role of angiogenesis in prostate cancer progression, we studied the growth of orthotopic PC-3 tumors overexpressing fibroblast growth factor b (FGF8b) known to be expressed in human prostate cancer. FGF8b increased tumor growth and angiogenesis, which were both associated with a characteristic gene expression pattern. To study the role of lymphangiogenesis, we produced orthotopic PC-3 tumors overexpressing vascular endothelial growth factor C (VEGF-C). Blocking of VEGF-C receptor (VEGFR3) completely inhibited lymph node metastasis whereas overexpression of VEGF-C increased tumor growth and angiogenesis. VEGF-C also increased lung metastases but, surprisingly, decreased spread to lymph nodes. This suggests that the expanded vascular network was primarily used as a route for tumor spreading. Finally, the functionality of the capillary network in subcutaneous FGF8b-overexpressing PC-3 tumors was compared to that of tumors overexpressing VEGF. Both tumors showed angiogenic morphology and grew faster than control tumors. However, FGF8b tumors were hypoxic and their perfusion and oxygenation was poor compared with VEGF tumors. This suggests that the growth advantage of FGF8b tumors is more likely due to stimulated proliferation than effective angiogenesis. In conclusion, these results show that orthotopic prostate tumors provide a useful model to explore the mechanisms of prostate cancer growth and metastasis.
Resumo:
In this work, a spectrophotometric methodology was applied in order to determine epinephrine (EP), uric acid (UA), and acetaminophen (AC) in pharmaceutical formulations and spiked human serum, plasma, and urine by using a multivariate approach. Multivariate calibration methods such as partial least squares (PLS) methods and its derivates were used to obtain a model for simultaneous determination of EP, UA and AC with good figures of merit and mixture design was in the range of 1.8 - 35.3, 1.7 - 16.8, and 1.5 - 12.1 µg mL-1. The 2nd derivate PLS showed recoveries of 95.3 - 103.3, 93.3 - 104.0, and 94.0 - 105.5 µg mL-1 for EP, UA, and AC, respectively.
Resumo:
If the mental can affect, or be affected by, the physical, then the mental must itself be physical. Otherwise the physical world would not be explanatorily closed. But it is closed. There are reasons to hold that materialism (in both its reductive and non-reductive varieties) is false. So how are we to explain the apparent responsiveness of the physical to the mental and vice versa? The only possible solution seems to be this: physical objects are really projections or isomorphs of objects whose essential properties are mental. (A slightly less accurate way of putting this would be to say: the constitutive - i.e. the non-structural and non-phenomenal - properties of physical objects are mental, i.e. are such as we are used to encountering only in "introspection".) The chair, qua thing that I can know through sense perception, and through hypotheses based strictly thereupon, is a kind of shadow of an object that is exactly like it, except that this other objects essential properties are mental. This line of thought, though radically counterintuitive, explains the apparent responsiveness of the mental to the physical, and vice versa, without being open to any of the criticisms to which materialism, dualistic interaction ism, and epiphenomenalism are open.
Resumo:
Metastatic bone lesions are commonly associated with prostate cancer affecting approximately 60-80% of the patients. The progression of prostate cancer into an advanced stage is a complex process and its molecular mechanisms are poorly understood. So far, no curative treatment is available for advanced stages of prostate cancer. Bisphosphonates (BPs) are synthetic pyrophosphate analogues, which are used as therapeutics for various metabolic bone diseases because of their ability to inhibit osteoclastic bone resorption. Nitrogen-containing bisphosphonates block the function of osteoclasts by disturbing the vesicular traffic and the mevalonate pathway -related enzymes, for example farnesyl diphosphate synthase, which is involved in post-translational isoprenylation of small GTPases. In addition, the anti-proliferative, anti-invasive and pro-apoptotic effects of nitrogen-containing bisphosphonates on various cancer cell lines have been reported. The aim of this thesis work was to clarify the effects of bisphosphonates on prostate cancer cells, focusing on the mechanisms of adhesion, invasion and migration. Furthermore, the role of the mevalonate pathway and prenylation reactions in invasion and regulation of the cytoskeleton of prostate cancer cells were examined. Finally, the effects of alendronate on cytoskeleton- and actin-related proteins in prostate cancer cells were studied in vitro and in vivo. The results showed that the nitrogen-containing bisphosphonate alendronate inhibited the adhesion of prostate cancer cells to various extracellular matrix proteins and migration and invasion in vitro. Inhibition of invasion and migration was reversed by mevalonate pathway intermediates. The blockage of the prenylation transferases GGTase I and FTase inhibited the invasion, migration and actin organization of prostate cancer cells. The marked decrease of cofilin was observed by the prenylation inhibitors used. Inhibition of GGTase I also disrupted the regulation of focal adhesion kinase and paxillin. In addition, alendronate disrupted the cytoskeletal organization and decreased the level of cofilin in vitro and in vivo. The decrease of the cofilin level by alendronate could be one of the key mechanisms behind the observed inhibition of migration and invasion. Based on the effects of nitrogen-containing bisphosphonates on tumor cell invasion and cytoskeletal organization, they can be suggested to be developed as therapeutics for inhibiting prostate cancer metastasis.
Resumo:
TMPRSS2–ERG is the most frequent type of genomic rearrangement present in prostate tumors, in which the 5- prime region of the TMPRSS2 gene is fused to the ERG oncogene. TMPRSS2, containing androgen response elements (AREs), is regulated by androgens in the prostate. The truncated TMPRSS2-ERG fusion transcript is overexpressed in half of the prostate cancer patients. The formation of TMPRSS2-ERG transcript is an early event in prostate carcinogenesis and previous in vivo and in vitro studies have shown ectopic ERG expression to be associated with increased cell invasion. However, the molecular function of ERG and its role in cell signaling is poorly understood. In this study, genomic rearrangement of ERG with TMPRSS2 was studied by using comparative genomic hybridization (CGH) in prostate cancer samples. The biological processes associated with the ERG oncogene expression in prostate epithelial cells were studied, and the results were compared with findings observed in clinical prostate tumor samples. The gene expression data indicated that increased WNT signaling and loss of cell adhesion were a characteristic of TMPRSS2- ERG fusion positive prostate tumor samples. Up- regulation of WNT pathway genes were present in ERG positive prostate tumors, with frizzled receptor 4 (FZD4) presenting with the highest association with ERG overexpression, as verified by quantitative reverse transcription-PCR, immunostaining, and immunoblotting in TMPRSS2-ERG positive VCaP prostate cancer cells. Furthermore, ERG and FZD4 silencing increased cell adhesion by inducing active β1-integrin and E-cadherin expression in VCaP cells. Furthermore, we found a novel inhibitor, 4-(chloromethyl) benzoyl chloride which inhibited the WNT signaling and induced similar phenotypic effects as observed after ERG or FZD4 down regulation in VCaP cells. In conclusion, this work deepens our understanding on the complex oncogenic mechanisms of ERG in prostate cancer that may help in developing drugs against TMPRSS2-ERG positive tumors.
Resumo:
Prostate cancers form a heterogeneous group of diseases and there is a need for novel biomarkers, and for more efficient and targeted methods of treatment. In this thesis, the potential of microarray data, RNA interference (RNAi) and compound screens were utilized in order to identify novel biomarkers, drug targets and drugs for future personalized prostate cancer therapeutics. First, a bioinformatic mRNA expression analysis covering 9873 human tissue and cell samples, including 349 prostate cancer and 147 normal prostate samples, was used to distinguish in silico prevalidated putative prostate cancer biomarkers and drug targets. Second, RNAi based high-throughput (HT) functional profiling of 295 prostate and prostate cancer tissue specific genes was performed in cultured prostate cancer cells. Third, a HT compound screen approach using a library of 4910 drugs and drug-like molecules was exploited to identify potential drugs inhibiting prostate cancer cell growth. Nine candidate drug targets, with biomarker potential, and one cancer selective compound were validated in vitro and in vivo. In addition to androgen receptor (AR) signaling, endoplasmic reticulum (ER) function, arachidonic acid (AA) pathway, redox homeostasis and mitosis were identified as vital processes in prostate cancer cells. ERG oncogene positive cancer cells exhibited sensitivity to induction of oxidative and ER stress, whereas advanced and castrate-resistant prostate cancer (CRPC) could be potentially targeted through AR signaling and mitosis. In conclusion, this thesis illustrates the power of systems biological data analysis in the discovery of potential vulnerabilities present in prostate cancer cells, as well as novel options for personalized cancer management.
Resumo:
Prostate cancer initially responds to hormone-based therapeutics such as anti-androgen treatment or chemotherapeutics but eventually becomes resistant. Novel treatment options are therefore urgently needed. This thesis study applied a high-throughput screen of 4910 known drugs and drug-like small molecules to identify compounds that selectively inhibit growth of prostate cancer cells. In addition, the mechanisms underlying the cellular sensitivity to potent cancer selective compounds were addressed. Surprisingly, many of the compounds currently used in the clinics or studied in clinical trials were not cancer-selective. Only four drugs, aldehyde dehydrogenase inhibitor disulfiram (Antabus), antibiotic ionophore monensin, histone deacetylase inhibitor tricostatin A and fungicide thiram inhibited prostate cancer cell growth at nanomolar concentrations without major effects on non-malignant prostate epithelial cells. Disulfiram, monensin and a structurally similar compound to monensin, salinomycin, induced oxidative stress and inhibited aldehyde dehydrogenase activity. Moreover, monensin and salinomycin reduced androgen receptor signalling and steroidogenesis, enforced cell differentiation and reduced the overall levels of cancer stem cells. Taken together, novel and potentially prostate cancer-selective therapeutic agents were identified in this study, including the description of a multitude of intoxicating mechanisms such as those relating to oxidative stress. The results provide novel insights into prostate cancer biology and exemplify useful means of considering novel approaches to cancer treatment.
Resumo:
Syftet med denna avhandling var att empiriskt undersöka kroppsbild, kroppsmissnöje och ätstörningssymptom hos vuxna i relation till kön och könsidentitet. Även sexuell kroppsbild studerades. Data samlades in via en populationsbaserad frågeformulärsstudie (11,468 deltagare) samt en intervjustudie med 20 transpersoner. Kvinnor rapporterade mer kroppsmissnöje och ätstörningssymptom än män. Till exempel uppgav mer än hälften av kvinnorna och en tredjedel av männen att de uppfattade sig som mindre attraktiva än de önskade att de var. Mer än hälften av kvinnorna och en tredjedel av männen uppgav sig banta, och självframkallade kräkningar rapporterades av var tionde kvinna och var hundrade man. Könsidentitetskonflikt var associerat med högre nivåer av kroppsnöje och ätstörningssymptom. Majoriteten av de intervjuade transpersonerna rapporterade omfattande missnöje med sina kroppar, särskilt gällande sexuell kroppsbild, samt ätstörningssymptom. Könskorrigering uppgavs i huvudsak lindra kroppsmissnöje och ätstörningssymptom. Vårdpersonal bör vara medveten om att kroppsmissnöje och ätstörningssymptom berör både vuxna kvinnor och män. Missnöje med de sexuella delarna av kroppen förefaller vara relativt vanligt bland vuxna och bör inte förbises. Vårdpersonal som arbetar med transpersoner bör vara medvetna om hur djupt och omfattande dessa personers kroppsmissnöje kan vara, samt uppmärksamma en eventuellt förhöjd risk för ätstörningssymptom. Det är även värt att notera att könskorrigering kan lindra kroppsmissnöje och ätstörningssymptom hos transpersoner.
Resumo:
ABSTRACT The Body Mass Index (BMI) can be used by farmers to help determine the time of evaluation of the body mass gain of the animal. However, the calculation of this index does not reveal immediately whether the animal is ready for slaughter or if it needs special care fattening. The aim of this study was to develop a software using the Fuzzy Logic to compare the bovine body mass among themselves and identify the groups for slaughter and those that requires more intensive feeding, using "mass" and "height" variables, and the output Fuzzy BMI. For the development of the software, it was used a fuzzy system with applications in a herd of 147 Nellore cows, located in a city of Santa Rita do Pardo city – Mato Grosso do Sul (MS) state, in Brazil, and a database generated by Matlab software.
Resumo:
Prostate-specific antigen (PSA) is a marker that is commonly used in estimating prostate cancer risk. Prostate cancer is usually a slowly progressing disease, which might not cause any symptoms whatsoever. Nevertheless, some cases of cancer are aggressive and need to be treated before they become life-threatening. However, the blood PSA concentration may rise also in benign prostate diseases and using a single total PSA (tPSA) measurement to guide the decision on further examinations leads to many unnecessary biopsies, over-detection, and overtreatment of indolent cancers which would not require treatment. Therefore, there is a need for markers that would better separate cancer from benign disorders, and would also predict cancer aggressiveness. The aim of this study was to evaluate whether intact and nicked forms of free PSA (fPSA-I and fPSA-N) or human kallikrein-related peptidase 2 (hK2) could serve as new tools in estimating prostate cancer risk. First, the immunoassays for fPSA-I and free and total hK2 were optimized so that they would be less prone to assay interference caused by interfering factors present in some blood samples. The optimized assays were shown to work well and were used to study the marker concentrations in the clinical sample panels. The marker levels were measured from preoperative blood samples of prostate cancer patients scheduled for radical prostatectomy. The association of the markers with the cancer stage and grade was studied. It was found that among all tested markers and their combinations especially the ratio of fPSA-N to tPSA and ratio of free PSA (fPSA) to tPSA were associated with both cancer stage and grade. They might be useful in predicting the cancer aggressiveness, but further follow-up studies are necessary to fully evaluate the significance of the markers in this clinical setting. The markers tPSA, fPSA, fPSA-I and hK2 were combined in a statistical model which was previously shown to be able to reduce unnecessary biopsies when applied to large screening cohorts of men with elevated tPSA. The discriminative accuracy of this model was compared to models based on established clinical predictors in reference to biopsy outcome. The kallikrein model and the calculated fPSA-N concentrations (fPSA minus fPSA-I) correlated with the prostate volume and the model, when compared to the clinical models, predicted prostate cancer in biopsy equally well. Hence, the measurement of kallikreins in a blood sample could be used to replace the volume measurement which is time-consuming, needs instrumentation and skilled personnel and is an uncomfortable procedure. Overall, the model could simplify the estimation of prostate cancer risk. Finally, as the fPSA-N seems to be an interesting new marker, a direct immunoassay for measuring fPSA-N concentrations was developed. The analytical performance was acceptable, but the rather complicated assay protocol needs to be improved until it can be used for measuring large sample panels.
Resumo:
The antiandrogenic therapy (ADT) for prostate cancer represents an additional risk factor for the development of osteoporosis and fragility fractures. Still, bone health of patients on ADT is often not evaluated. After literature research we found that simple preventive measures can prevent bone loss in these patients, resulting in more cost-effective solutions to the public health system and family when compared to the treatment of fractures.