993 resultados para Stefan Haupt


Relevância:

10.00% 10.00%

Publicador:

Resumo:

BACKGROUND: Tumorigenesis is characterised by changes in transcriptional control. Extensive transcript expression data have been acquired over the last decade and used to classify prostate cancers. Prostate cancer is, however, a heterogeneous multifocal cancer and this poses challenges in identifying robust transcript biomarkers.

METHODS: In this study, we have undertaken a meta-analysis of publicly available transcriptomic data spanning datasets and technologies from the last decade and encompassing laser capture microdissected and macrodissected sample sets.

RESULTS: We identified a 33 gene signature that can discriminate between benign tissue controls and localised prostate cancers irrespective of detection platform or dissection status. These genes were significantly overexpressed in localised prostate cancer versus benign tissue in at least three datasets within the Oncomine Compendium of Expression Array Data. In addition, they were also overexpressed in a recent exon-array dataset as well a prostate cancer RNA-seq dataset generated as part of the The Cancer Genomics Atlas (TCGA) initiative. Biologically, glycosylation was the single enriched process associated with this 33 gene signature, encompassing four glycosylating enzymes. We went on to evaluate the performance of this signature against three individual markers of prostate cancer, v-ets avian erythroblastosis virus E26 oncogene homolog (ERG) expression, prostate specific antigen (PSA) expression and androgen receptor (AR) expression in an additional independent dataset. Our signature had greater discriminatory power than these markers both for localised cancer and metastatic disease relative to benign tissue, or in the case of metastasis, also localised prostate cancer.

CONCLUSION: In conclusion, robust transcript biomarkers are present within datasets assembled over many years and cohorts and our study provides both examples and a strategy for refining and comparing datasets to obtain additional markers as more data are generated.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Cellular stress responses often involve elevation of cytosolic calcium levels, and this has been suggested to stimulate autophagy. Here, however, we demonstrated that agents that alter intracellular calcium ion homeostasis and induce ER stress-the calcium ionophore A23187 and the sarco/endoplasmic reticulum Ca (2+)-ATPase inhibitor thapsigargin (TG)-potently inhibit autophagy. This anti-autophagic effect occurred under both nutrient-rich and amino acid starvation conditions, and was reflected by a strong reduction in autophagic degradation of long-lived proteins. Furthermore, we found that the calcium-modulating agents inhibited autophagosome biogenesis at a step after the acquisition of WIPI1, but prior to the closure of the autophagosome. The latter was evident from the virtually complete inability of A23187- or TG-treated cells to sequester cytosolic lactate dehydrogenase. Moreover, we observed a decrease in both the number and size of starvation-induced EGFP-LC3 puncta as well as reduced numbers of mRFP-LC3 puncta in a tandem fluorescent mRFP-EGFP-LC3 cell line. The anti-autophagic effect of A23187 and TG was independent of ER stress, as chemical or siRNA-mediated inhibition of the unfolded protein response did not alter the ability of the calcium modulators to block autophagy. Finally, and remarkably, we found that the anti-autophagic activity of the calcium modulators did not require sustained or bulk changes in cytosolic calcium levels. In conclusion, we propose that local perturbations in intracellular calcium levels can exert inhibitory effects on autophagy at the stage of autophagosome expansion and closure.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Metabolic changes are a well-described hallmark of cancer and are responses to changes in the activity of diverse oncogenes and tumour suppressors. For example, steroid hormone biosynthesis is intimately associated with changes in lipid metabolism and represents a therapeutic intervention point in the treatment of prostate cancer (PCa). Both prostate gland development and tumorigenesis rely on the activity of a steroid hormone receptor family member, the androgen receptor (AR). Recent studies have sought to define the biological effect of the AR on PCa by defining the whole-genome binding sites and gene networks that are regulated by the AR. These studies have provided the first systematic evidence that the AR influences metabolism and biosynthesis at key regulatory steps within pathways that have also been defined as points of influence for other oncogenes, including c-Myc, p53 and hypoxia-inducible factor 1α, in other cancers. The success of interfering with these pathways in a therapeutic setting will, however, hinge on our ability to manage the concomitant stress and survival responses induced by such treatments and to define appropriate therapeutic windows.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

To gain insight into IL5 receptor subunit recruitment mechanism, and in particular the experimentally elusive pathway for assembly of signaling subunit beta(c), we constructed a soluble beta(c) ectodomain (s(beta)(c)) and developed an optical biosensor assay to measure its binding kinetics. Functionally active s(beta)(c) was anchored via a C-terminal His tag to immobilized anti-His monoclonal antibodies on the sensor surface. Using this surface, we quantitated for the first time direct binding of s(beta)(c) to IL5R(alpha) complexed to either wild-type or single-chain IL5. Binding was much weaker if at all with either R(alpha) or IL5 alone. Kinetic evaluation revealed a moderate affinity (0.2-1 microM) and relatively fast off rate for the s(beta)(c) interaction with IL5:R(alpha) complexes. The data support a model in which beta(c) recruitment occurs with preformed IL5:R(alpha) complex. Dissociation kinetics analysis suggests that the IL5-alpha-beta(c) complex is relatively short-lived. Overall, this study solidifies a model of sequential recruitment of receptor subunits by IL5, provides a novel biosensor binding assay of beta(c) recruitment dynamics, and sets the stage for more advanced characterization of the roles of structural elements within R(alpha), beta(c), and cytokines of the IL5/IL3/GM-CSF family in receptor recruitment and activation.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Tumor recurrence after curative resection remains a major problem in patients with locally advanced colorectal cancer treated with adjuvant chemotherapy. Genetic single-nucleotide polymorphisms (SNP) may serve as useful molecular markers to predict clinical outcomes in these patients and identify targets for future drug development. Recent in vitro and in vivo studies have demonstrated that the plastin genes PLS3 and LCP1 are overexpressed in colon cancer cells and play an important role in tumor cell invasion, adhesion, and migration. Hence, we hypothesized that functional genetic variations of plastin may have direct effects on the progression and prognosis of locally advanced colorectal cancer. We tested whether functional tagging polymorphisms of PLS3 and LCP1 predict time to tumor recurrence (TTR) in 732 patients (training set, 234; validation set, 498) with stage II/III colorectal cancer. The PLS3 rs11342 and LCP1 rs4941543 polymorphisms were associated with a significantly increased risk for recurrence in the training set. PLS3 rs6643869 showed a consistent association with TTR in the training and validation set, when stratified by gender and tumor location. Female patients with the PLS3 rs6643869 AA genotype had the shortest median TTR compared with those with any G allele in the training set [1.7 vs. 9.4 years; HR, 2.84; 95% confidence interval (CI), 1.32-6.1; P = 0.005] and validation set (3.3 vs. 13.7 years; HR, 2.07; 95% CI, 1.09-3.91; P = 0.021). Our findings suggest that several SNPs of the PLS3 and LCP1 genes could serve as gender- and/or stage-specific molecular predictors of tumor recurrence in stage II/III patients with colorectal cancer as well as potential therapeutic targets.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Background: The nature and underlying mechanisms of an inverse association between adult height and the risk of coronary artery disease (CAD) are unclear. 
Methods: We used a genetic approach to investigate the association between height and CAD, using 180 height-associated genetic variants. We tested the association between a change in genetically determined height of 1 SD (6.5 cm) with the risk of CAD in 65,066 cases and 128,383 controls. Using individual-level genotype data from 18,249 persons, we also examined the risk of CAD associated with the presence of various numbers of height-associated alleles. To identify putative mechanisms, we analyzed whether genetically determined height was associated with known cardiovascular risk factors and performed a pathway analysis of the height-associated genes. 
Results: We observed a relative increase of 13.5% (95% confidence interval [CI], 5.4 to 22.1; P<0.001) in the risk of CAD per 1-SD decrease in genetically determined height. There was a graded relationship between the presence of an increased number of height-raising variants and a reduced risk of CAD (odds ratio for height quartile 4 versus quartile 1, 0.74; 95% CI, 0.68 to 0.84; P<0.001). Of the 12 risk factors that we studied, we observed significant associations only with levels of low-density lipoprotein cholesterol and triglycerides (accounting for approximately 30% of the association). We identified several overlapping pathways involving genes associated with both development and atherosclerosis. 
Conclusions: There is a primary association between a genetically determined shorter height and an increased risk of CAD, a link that is partly explained by the association between shorter height and an adverse lipid profile. Shared biologic processes that determine achieved height and the development of atherosclerosis may explain some of the association. (Funded by the British Heart Foundation and others.)

Relevância:

10.00% 10.00%

Publicador:

Resumo:

We present photometric and spectroscopic observations of the interacting transient SN 2009ip taken during the 2013 and 2014 observing seasons. We characterize the photometric evolution as a steady and smooth decline in all bands, with a decline rate that is slower than expected for a solely Co-56-powered supernova at late phases. No further outbursts or eruptions were seen over a two year period from 2012 December until 2014 December. SN 2009ip remains brighter than its historic minimum from pre-discovery images. Spectroscopically, SN 2009ip continues to be dominated by strong, narrow (less than or similar to 2000 km s(-1)) emission lines of H, He, Ca, and Fe. While we make tenuous detections of [Fe II] lambda 7155 and [O I] lambda lambda 6300, 6364 lines at the end of 2013 June and the start of 2013 October, respectively, we see no strong broad nebular emission lines that could point to a core-collapse origin. In general, the lines appear relatively symmetric, with the exception of our final spectrum in 2014 May, when we observe the appearance of a redshifted shoulder of emission at +550 km s(-1). The lines are not blueshifted, and we see no significant near-or mid-infrared excess. From the spectroscopic and photometric evolution of SN 2009ip until 820 d after the start of the 2012a event, we still see no conclusive evidence for core-collapse, although whether any such signs could be masked by ongoing interaction is unclear.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The European Cystic Fibrosis Society Clinical Trial Network (ECFS-CTN) has established a Standardization Committee to undertake a rigorous evaluation of promising outcome measures with regard to use in multicentre clinical trials in cystic fibrosis (CF). The aim of this article is to present a review of literature on clinimetric properties of the infant raised-volume rapid thoracic compression (RVRTC) technique in the context of CF, to summarise the consensus amongst the group on feasibility and answer key questions regarding the promotion of this technique to surrogate endpoint status.

METHODS: A literature search (from 1985 onwards) identified 20 papers that met inclusion criteria of RVRTC use in infants with CF. Data were extracted and tabulated regarding repeatability, validity, correlation with other outcome measures, responsiveness and reference values. A working group discussed the tables and answered 4 key questions.

RESULTS: Overall, RVRTC in particular forced expiratory volume in 0.5s, showed good clinimetric properties despite presence of individual variability. Few studies showed a relationship between RVRTC and inflammation and infection, and to date, data remains limited regarding the responsiveness of RVRTC after an intervention. Concerns were raised regarding feasibility in multi-centre studies and availability of reference values.

CONCLUSION: The ECFS-CTN Working Group considers that RVRTC cannot be used as a primary outcome in clinical trials in infants with CF before universal standardization of this measurement is achieved and implementation of inter-institutional networking is in place. We advise its use currently in phase I/II trials and as a secondary endpoint in phase III studies. We emphasise the need for (1) more short-term variability and longitudinal 'natural history' studies, and (2) robust reference values for commercially available devices.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Prostate cancer (PCa) is the most prevalent cancer in men. Hyperactive STAT3 is thought to be oncogenic in PCa. However, targeting of the IL-6/STAT3 axis in PCa patients has failed to provide therapeutic benefit. Here we show that genetic inactivation of Stat3 or IL-6 signalling in a Pten-deficient PCa mouse model accelerates cancer progression leading to metastasis. Mechanistically, we identify p19(ARF) as a direct Stat3 target. Loss of Stat3 signalling disrupts the ARF-Mdm2-p53 tumour suppressor axis bypassing senescence. Strikingly, we also identify STAT3 and CDKN2A mutations in primary human PCa. STAT3 and CDKN2A deletions co-occurred with high frequency in PCa metastases. In accordance, loss of STAT3 and p14(ARF) expression in patient tumours correlates with increased risk of disease recurrence and metastatic PCa. Thus, STAT3 and ARF may be prognostic markers to stratify high from low risk PCa patients. Our findings challenge the current discussion on therapeutic benefit or risk of IL-6/STAT3 inhibition.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The use of portion control practices has rarely been quantified. The present study aimed to: (1) explore which portion control practices are actually used by the general population and their association with cognitive restraint, demographic background and general health interest (GHI), and (2) examine how the usage of portion control practices predicts the estimated consumption of an energy dense food (i.e. pizza). Twenty-two portion control practices were rated in terms of their frequency of use from 'never' to 'very often' by a representative sample of 1012 consumers from the island of Ireland. Three factors were extracted and named: measurement-strategy scale, eating-strategy scale, and purchasing-strategy scale. The eating-strategy scale score was the highest, while the measurement-strategy scale carried the lowest frequency score. For each strategy scale score, the strongest predictor was GHI, followed by gender. Having higher GHI and being female were independently associated with more frequent portion control. Both the eating-strategy scale score and the purchasing-strategy scale score were negatively associated with pizza portion size consumption estimates. In conclusion, while this study demonstrates that the reported use of portion control practices is low, the findings provide preliminary evidence for their validity. Further studies are needed to explore how portion control practices are used in different kinds of portion size decisions and what their contribution is to the intake of food over an extended period of time.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The coast of the Bulgarian Black Sea is a popular summer holiday destination. The Dam of Iskar is the largest artificial dam in Bulgaria, with a capacity of 675 million m3. It is the main source of tap water for the capital Sofia and for irrigating the surrounding valley. There is a close relationship between the quality of aquatic ecosystems and human health as many infections are waterborne. Rapid molecular methods for the analysis of highly pathogenic bacteria have been developed for monitoring quality. Mycobacterial species can be isolated from waste, surface, recreational, ground and tap waters and human pathogenicity of nontuberculose mycobacteria (NTM) is well recognized. The objective of our study was to perform molecular analysis for key-pathogens, with a focus on mycobacteria, in water samples collected from the Black Sea and the Dam of Iskar. In a two year period, 38 water samples were collected-24 from the Dam of Iskar and 14 from the Black Sea coastal zone. Fifty liter water samples were concentrated by ultrafiltration. Molecular analysis for 15 pathogens, including all species of genus Mycobacterium was performed. Our results showed presence of Vibrio spp. in the Black Sea. Rotavirus A was also identified in four samples from the Dam of Iskar. Toxigenic Escherichia coli was present in both locations, based on markers for stx1 and stx2 genes. No detectable amounts of Cryptosporidium were detected in either location using immunomagnetic separation and fluorescence microscopy. Furthermore, mass spectrometry analyses did not detect key cyanobacterial toxins. On the basis of the results obtained we can conclude that for the period 2012-2014 no Mycobacterium species were present in the water samples. During the study period no cases of waterborne infections were reported.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The Casimir force in a system consisting of two parallel conducting plates in the presence of compactified universal extra dimensions (UXD) is analyzed. The Casimir force with UXDs differs from the force obtained without extra dimensions. A new power law for the Casimir force is derived. By comparison to experimental data the size R of the universal extra dimensions can be restricted to R⩽10 nm for one extra dimension.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Purpose:
Social norms influence eating behavior, but little is known about their role in portion size-related behavior. This study
explored the role of social eating norms in Denmark (DK) and the Island of Ireland (IOI) in relation to portion size-related
behavior.

Methods:
In a survey DK (n=1063) and IOI (n=1012) respondents rated social eating norms (11 items) and portion size-related behavior
(3 items) on a 7-point scale (1=strongly disagree to 7=strongly agree). The 3 items relate to: 1) anticipating how
much will be eaten at the beginning of a meal, 2) clearing the plate, and 3) clearing the plate even when full. Sociodemographics
and eating attitudes (e.g. cognitive restraint) were measured as background variables

Results:
Two social eating factors were identified: The ‘limit intake’ norm (6 items) and the ‘plate cleaning’ norm (3 items). The
DK participants reported stronger ‘limit intake’ norms and weaker ‘plate cleaning’ norms than IOI. In both countries
females reported stronger ‘limit intake’ norms while males reported stronger ‘plate cleaning’ norms. In DK, age was
positively correlated with both social eating norm factors. The ‘limit intake’ norm had stronger association with anticipating
how much will be eaten at the beginning of a meal, but the ‘plate cleaning’ norm had stronger association with
clearing the plate. Only the ‘plate cleaning’ norm was associated with clearing the plate even when full.

Conclusions:
The social eating norms vary significantly between countries and genders. The ‘limit intake’ and ‘plate cleaning’ norms
play a role in consumers’ reported portion size-related behavior.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Purpose:
This study explored how meal-related variables, socio-demographics and psychological predispositions affect the portion
size and perceived fillingness of an evening meal in Danish and Irish households.
Methods:
Using survey data collected in 2115 respondents from Denmark (DK) and the Island of Ireland (IOI), we compared four
sets of predictors of the portion size chosen for four evening meals (i.e. pizza/soup/chicken salad/pork meal): Biological
variables (hunger, thirst), socio-demographic variables (gender, age, BMI); psychological predispositions (cognitive
restraint, uncontrolled eating, emotional eating, general health interest) and meal-related variables (expected fillingness,
perceived healthiness, liking, frequency of consumption). We also compared five sets of predictors (the previous
four plus portion size) of perceived portion fillingness.
Results:
Portion size selections were associated mainly with demographic variables (gender, BMI) and psychological predispositions
(cognitive restraint, uncontrolled eating). In addition, only liking and sometimes expected healthiness (mealrelated
variables) appeared as drivers. Conversely, perceived portion fillingness was mostly influenced by the selected
portion size as well as expected fillingness and liking. There were some differences between meals; e.g. GHI not a
predictor for Pizza but a predictor for Chicken salad. Also some country differences were observed; emotional eating
predicted portion selection in the IOI but not DK.
Conclusions:
When making portion size selections at home, psychological predispositions, restrained and uncontrolled eating as well
as meal-related variables, liking and healthiness explained the decisions. However, surprisingly, individuals’ expected
fillingness of a food did not influence their portion size selection but was a driver of fillingness of the selected portion.