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Background: The phagocytic enzyme myeloperoxidase (MPO) acts as a front-line defender against microorganisms. However, increased MPO levels have been found to be associated with complex and calcified atherosclerotic lesions and incident cardiovascular disease. Therefore, this study aimed to investigate a predictive role of MPO, a biomarker of inflammation and oxidative stress, for total and cardiovascular mortality in patients referred to coronary angiography.
Methods and results: MPO plasma concentrations along with eight MPO polymorphisms were determined in 3036 participants of the Ludwigshafen Risk and Cardiovascular Health study (median follow-up 7.75 years). MPO concentrations were positively associated with age, diabetes, smoking, markers of systemic inflammation (interleukin-6, fibrinogen, C-reactive protein, serum amyloid A) and vascular damage (vascular cellular adhesion molecule-1 and intercellular adhesion molecule-1) but negatively associated with HDL-cholesterol and apolipoprotein A-I. After adjustment for cardiovascular risk factors MPO concentrations in the highest versus the lowest quartile were associated with a 1.34-fold risk (95% CI: 1.09–1.67) for total mortality. In the adjusted model the hazard ratio for cardiovascular mortality in the highest MPO quartile was 1.42 (95% CI: 1.07–1.88). Five MPO polymorphisms were positively associated with MPO concentrations but not with mortality. Using Mendelian randomization, we did not obtain evidence for a causal association of MPO with either total or cardiovascular mortality.
Conclusions: MPO concentrations but not genetic variants at the MPO locus are independently associated with risk for total and cardiovascular mortality in coronary artery disease patients.
Glioblastoma multiforme (GBM) is a deadly primary brain malignancy. Glioblastoma stem cells (GSC), which have the ability to self-renew and differentiate into tumor lineages, are believed to cause tumor recurrence due to their resistance to current therapies. A subset of GSCs is marked by cell surface expression of CD133, a glycosylated pentaspan transmembrane protein. The study of CD133-expressing GSCs has been limited by the relative paucity of genetic tools that specifically target them. Here, we present CD133-LV, a lentiviral vector presenting a single chain antibody against CD133 on its envelope, as a vehicle for the selective transduction of CD133-expressing GSCs. We show that CD133-LV selectively transduces CD133+ human GSCs in dose-dependent manner and that transduced cells maintain their stem-like properties. The transduction efficiency of CD133-LV is reduced by an antibody that recognizes the same epitope on CD133 as the viral envelope and by shRNA-mediated knockdown of CD133. Conversely, the rate of transduction by CD133-LV is augmented by overexpression of CD133 in primary human GBM cultures. CD133-LV selectively transduces CD133-expressing cells in intracranial human GBM xenografts in NOD.SCID mice, but spares normal mouse brain tissue, neurons derived from human embryonic stem cells and primary human astrocytes. Our findings indicate that CD133-LV represents a novel tool for the selective genetic manipulation of CD133-expressing GSCs, and can be used to answer important questions about how these cells contribute to tumor biology and therapy resistance.
Escherichia coli α-hemolysin (HlyA) is a pore-forming protein of 110 kDa belonging to the family of RTX toxins. A hydrophobic region between the amino acid residues 238 and 410 in the N-terminal half of HlyA has previously been suggested to form hydrophobic and/or amphipathic α-helices and has been shown to be important for hemolytic activity and pore formation in biological and artificial membranes. The structure of the HlyA transmembrane channel is, however, largely unknown. For further investigation of the channel structure, we deleted in HlyA different stretches of amino acids that could form amphipathic β-strands according to secondary structure predictions (residues 71–110, 158–167, 180–203, and 264–286). These deletions resulted in HlyA mutants with strongly reduced hemolytic activity. Lipid bilayer measurements demonstrated that HlyAΔ71–110 and HlyAΔ264–286 formed channels with much smaller single-channel conductance than wildtype HlyA, whereas their channel-forming activity was virtually as high as that of the wildtype toxin. HlyAΔ158–167 and HlyAΔ180–203 were unable to form defined channels in lipid bilayers. Calculations based on the single-channel data indicated that the channels generated by HlyAΔ71–110 and HlyAΔ264–286 had a smaller size (diameter about 1.4 to 1.8 nm) than wildtype HlyA channels (diameter about 2.0 to 2.6 nm), suggesting that in these mutants part of the channel-forming domain was removed. Osmotic protection experiments with erythrocytes confirmed that HlyA, HlyAΔ71–110, and HlyAΔ264–286 form defined transmembrane pores and suggested channel diameters that largely agreed with those estimated from the single-channel data. Taken together, these results suggest that the channel-forming domain of HlyA might contain β-strands, possibly in addition to α-helical structures.
Previously we reported modulation of endothelial prostacyclin and interleukin-8 production, cyclooxygenase-2 expression and vasorelaxation by oleoyl-lysophosphatidylcholine (LPC 18:1). In the present study, we examined the impact of this LPC on nitric oxide (NO) bioavailability in vascular endothelial EA.hy926 cells. Basal NO formation in these cells was decreased by LPC 18:1. This was accompanied with a partial disruption of the active endothelial nitric oxide synthase (eNOS)-dimer, leading to eNOS uncoupling and increased formation of reactive oxygen species (ROS). The LPC 18:1-induced ROS formation was attenuated by the superoxide scavenger Tiron, as well as by the pharmacological inhibitors of eNOS, NADPH oxidases, flavin-containing enzymes and superoxide dismutase (SOD). Intracellular ROS-formation was most prominent in mitochondria, less pronounced in cytosol and undetectable in endoplasmic reticulum. Importantly, Tiron completely prevented the LPC 18:1-induced decrease in NO bioavailability in EA.hy926 cells. The importance of the discovered findings for more in vivo like situations was analyzed by organ bath experiments in mouse aortic rings. LPC 18:1 attenuated the acetylcholine-induced, endothelium dependent vasorelaxation and massively decreased NO bioavailability. We conclude that LPC 18:1 induces eNOS uncoupling and unspecific superoxide production. This results in NO scavenging by ROS, a limited endothelial NO bioavailability and impaired vascular function.
Myotonic dystrophy type 1 (DM1) lacks non-invasive and easy to measure biomarkers, still largely relying on semi-quantitative tests for diagnostic and prognostic purposes. Muscle biopsies provide valuable data, but their use is limited by their invasiveness. microRNA (miRNAs) are small non-coding RNAs regulating gene expression that are also present in biological fluids and may serve as diseases biomarkers. Thus, we tested plasma miRNAs in the blood of 36 DM1 patients and 36 controls. First, a wide miRNA panel was profiled in a patient subset, followed by validation using all recruited subjects. We identified a signature of nine deregulated miRNAs in DM1 patients: eight miRNAs were increased (miR-133a, miR-193b, miR-191, miR-140-3p, miR-454, miR-574, miR-885-5p, miR-886-3p) and one (miR-27b) was decreased. Next, the levels of these miRNAs were used to calculate a "DM1-miRNAs score". We found that both miR-133a levels and DM1-miRNAs score discriminated DM1 from controls significantly and Receiver-Operator Characteristic curves displayed an area under the curve of 0.94 and 0.97, respectively. Interestingly, both miR-133a levels and DM1-miRNAs score displayed an inverse correlation with skeletal muscle strength and displayed higher values in more compromised patients. In conclusion, we identified a characteristic plasma miRNA signature of DM1. Although preliminary, this study indicates miRNAs as potential DM1 humoral biomarkers.
Bei Knochendefekten kritischer Größe ist es notwendig, den Knochen bei der Heilung zu unterstützen. Der derzeitige Goldstandard bei der Behandlung von critical size defects ist die Entnahme von autologem Knochen aus dem Beckenkamm, dies ist jedoch mit Nachteilen wie Entnahmemorbidität und Limitierung der entnehmbaren Menge vergesellschaftet. Das Knochen tissue engineering, bei welchem regenerative Zellen mit einem Knochenersatzmaterial kombiniert werden, könnte eine vielversprechende Alternative sein. Stromale Knochenmarkzellen, die Osteoblasten differenzieren können, und endotheliale Vorläuferzellen, die die Vaskularisierung der Defektzone unterstützen, zeigten sich effektiv in tierexperimentellen Studien; jedoch müssen diese Zellen vor Verwendung über einen längeren Zeitraum in Kultur expandiert werden. Dies kann jedoch zu einer Akkumulation genetischer Schäden und möglicherweise zu einer Entartung der transplantierten Zellen führen. Bone marrow mononuclear cells (BMC) stellen eine interessante Alternative dar, sie können innerhalb weniger Stunden isoliert und dem Patienten zurückgegeben werden. Ziel dieser Arbeit war daher, die Adhäsion und funktionelle Aspekte von BMC auf drei verschiedenen Knochenersatzmaterialien zu analysieren.
Im ersten Versuchsteil wurde untersucht, ob es möglich ist, BMC auf einem β-Tricalciumphosphat (β-TCP)-Scaffold auszusäen, und ob eine Beschichtung des Scaffolds eine positive Auswirkung auf die BMC-Adhäsion und Aktivität hat. Hierbei wurde eine Beschichtung mit humanem Plasma (FFP) und Fibronektin gegen eine Kontrolle verglichen. Es konnte gezeigt werden, dass BMC auf unbeschichtetem β-TCP adhärieren und dass eine Vorbeschichtung des Scaffolds mit Fibronektin oder mit FFP zu keiner weiteren Verbesserung der initialen Adhäsion führt. FACS-Analysen zeigten, dass der Prozentsatz der auf dem Material adhärierenden Fraktionen regenerativer Zellen dem Prozentsatz der in der Kontrolle enthaltenen regenerativen Zellen entspricht. Überdies konnte eine endotheliale Differenzierung der ausgesäten BMC beobachtet werden. Die Anzahl adhärierender BMC war zum ersten Messpunkt an Tag zwei unabhängig von der Vorbeschichtung am höchsten. Interessanterweise war die Zahl der adhärierenden BMC auf unbeschichtetem Material signifikant gegenüber den beschichteten Materialien erhöht.
Basierend auf der Beobachtung, dass eine Vorbeschichtung der Trägersubstanz nicht zu einer Verbesserung der BMC-Adhäsion auf dem Gerüststoff führt, wurden im zweiten Versuchsteil unbeschichtete Gerüststoffe miteinander verglichen. Für diese Arbeit wurden drei aus verschiedenen Klassen der Knochenersatzmaterialien stammende Scaffolds gewählt. ChronOs® als Vertreter der β-TCPs, Cerabone®, eine verarbeitete bovine Knochenmatrix, und Demineralized Bone Matrix (DBM), ein sterilisiertes humanes Knochentransplantat. Die Untersuchungen ergaben signifikante Unterschiede in der Aussaateffizienz der Zellen auf den Materialien und der Zellaktivität im Verlauf über 21 Tage. DBM zeigte hier im Materialvergleich die besten Ergebnisse. In unserem Versuch zeigte sich die Menge der absorbierten Flüssigkeit im Verhältnis zur Materialmenge bei DBM signifikant erhöht gegenüber den beiden anderen Materialien. Zudem konnte mittels HE- und Kern-Färbung (DAPI) der Nachweis erbracht werden, dass sich Zellen tief im Inneren des Materials anlagern. MTT-Tests zeigten an Tag 14 eine signifikant erhöhte metabolische Aktivität auf DBM gegenüber Cerabone® und an Tag 21 gegenüber beiden Vergleichsmatrices. Wir konnten auf allen Materialien an Tag 2 eine signifikant erhöhte VEGF-Produktion feststellen. Mittels Real-Time-PCR ließ sich eine VEGF-Genexpression in BMC auf allen Materialien bis Tag 14 und auf DBM über die kompletten 21 Tage nachweisen. Die Genexpression von vWF konnte ebenfalls auf allen Materialien über den gesamten Zeitraum nachgewiesen werden.
Zusammengefasst konnte durch diese Studie belegt werden, dass die initiale Adhärenz von BMC auf unbeschichtete Knochenersatzmaterialien generell hoch ist, aber signifikante materialspezifische Unterschiede in der Aussaateffizienz und nachfolgend der metabolischen Aktivität und der VEGFSynthese der BMC existieren. Humanes Knochenersatzmaterial zeigte sich in unserer Studie als überlegen. Daher sollte die Art des Knochenersatzmaterials für den künftigen klinischen Einsatz von BMC Berücksichtigung finden.
The neuroanatomical connectivity of cortical circuits is believed to follow certain rules, the exact origins of which are still poorly understood. In particular, numerous nonrandom features, such as common neighbor clustering, overrepresentation of reciprocal connectivity, and overrepresentation of certain triadic graph motifs have been experimentally observed in cortical slice data. Some of these data, particularly regarding bidirectional connectivity are seemingly contradictory, and the reasons for this are unclear. Here we present a simple static geometric network model with distance-dependent connectivity on a realistic scale that naturally gives rise to certain elements of these observed behaviors, and may provide plausible explanations for some of the conflicting findings. Specifically, investigation of the model shows that experimentally measured nonrandom effects, especially bidirectional connectivity, may depend sensitively on experimental parameters such as slice thickness and sampling area, suggesting potential explanations for the seemingly conflicting experimental results.
Background: High-dose chemotherapy (HDC) with autologous stem-cell rescue (ASCR) is a treatment option for pediatric patients with relapsed nephroblastoma. We present long term results of 9 patients treated between 1993 and 2013 at our center.
Procedure: Reinduction therapy was carried out according to GPOH and SIOP recommendations. The conditioning regimen consisted of carboplatin (1 200 mg/m²), etoposide (800 mg/m² or 40 mg/kg) and melphalan (180 mg/m²). Purging of the grafts with immunomagnetic CD34 positive selection was performed in 5 patients.
Results: 8 of 9 Patients (90%) are alive without evidence of disease after a median follow-up of 8.5 years. Leukocyte engraftment occurred after a median of 10 days (range 8-12). Median numbers of 667/µl CD3+, 329/µl CD4+, 369/µl CD8+T cells and 949/µl B cells were reached after 180 days. No negative impact of CD34 selection was observed. No transplantation-related death occurred. Acute toxicity comprised mucositis III°-IV° in all and veno-occlusive disease in one patient. Long term effects probably related to treatment occurred in 3/7 evaluable patients and comprised hearing impairment, reduced renal phosphate reabsorption, mild creatinine elevation and hypothyroidism (n=1, each).
Conclusion: Thus, in our experience HDC with ASCR is an effective treatment of recurrent or refractory nephroblastoma with acceptable side effects. However, a randomized trial proving its efficiency with a high level of evidence is needed.
Objective: To examine risk of malignancy and death in patients with kidney transplant who receive the immunosuppressive drug sirolimus.
Design: Systematic review and meta-analysis of individual patient data.
Data sources: Medline, Embase, and the Cochrane Central Register of Controlled Trials from inception to March 2013.
Eligibility: Randomized controlled trials comparing immunosuppressive regimens with and without sirolimus in recipients of kidney or combined pancreatic and renal transplant for which the author was willing to provide individual patient level data. Two reviewers independently screened titles/abstracts and full text reports of potentially eligible trials to identify studies for inclusion. All eligible trials reported data on malignancy or survival.
Results: The search yielded 2365 unique citations. Patient level data were available from 5876 patients from 21 randomized trials. Sirolimus was associated with a 40% reduction in the risk of malignancy (adjusted hazard ratio 0.60, 95% confidence interval 0.39 to 0.93) and a 56% reduction in the risk of non-melanoma skin cancer (0.44, 0.30 to 0.63) compared with controls. The most pronounced effect was seen in patients who converted to sirolimus from an established immunosuppressive regimen, resulting in a reduction in risk of malignancy (0.34, 0.28 to 0.41), non-melanoma skin cancer (0.32, 0.24 to 0.42), and other cancers (0.52, 0.38 to 0.69). Sirolimus was associated with an increased risk of death (1.43, 1.21 to 1.71) compared with controls.
Conclusions: Sirolimus was associated with a reduction in the risk of malignancy and non-melanoma skin cancer in transplant recipients. The benefit was most pronounced in patients who converted from an established immunosuppressive regimen to sirolimus. Given the risk of mortality, however, the use of this drug does not seem warranted for most patients with kidney transplant. Further research is needed to determine if different populations, such as those at high risk of cancer, might benefit from sirolimus.
Tumor cell plasticity is an event that has been observed in several malignancies. In fact, most of the solid tumors are characterized by cellular heterogeneity and undergo constant changes as the tumor develops. The increased plasticity displayed by these cells allows them to acquire additional properties, enabling epithelial-mesenchymal transitions, dedifferentiation and the acquisition of stem cell-like properties. Here we discuss the particular importance of an inflammatory microenvironment for the bidirectional control of cellular plasticity and the potential for therapeutic intervention.
Background: Oral anticoagulation (OAC) with coumarins and new anticoagulants are highly effective in preventing thromboembolic complications. However, some studies indicate that over- and under-treatment with anticoagulants are fairly common. The aim of this paper is to assess the appropriateness of treatment in patients with a long-term indication for OAC, and to describe the corresponding characteristics of such patients on the basis of screening results from the cluster randomized PICANT trial.
Methods: Randomly selected family practices in the federal state of Hesse, Germany, were visited by study team members. Eligible patients were screened using an anonymous patient list that was generated by the general practitioners? software according to predefined instructions. A documentation sheet was filled in for all screened patients. Eligible patients were classified into 3 categories (1: patients with a long-term indication for OAC and taking anticoagulants, 2: patients with a long-term indication for OAC but not taking anticoagulants, 3: patients without a long-term indication for OAC but taking an anticoagulant on a permanent basis). IBM SPSS Statistics 20 was used for descriptive statistical analysis.
Results: We screened 2,036 randomly selected, potentially eligible patients from 52 family practices. 275 patients could not be assigned to one of the 3 categories and were therefore not considered for analysis. The final study sample comprised 1,761 screened patients, 1,641 of whom belonged to category 1, 78 to category 2, and 42 to category 3. INR values were available for 1,504 patients of whom 1,013 presented INR values within their therapeutic ranges. The majority of screened patients had very good compliance, as assessed by the general practitioner. New antithrombotic drugs were prescribed in 6.1% of cases.
Conclusions: The screening results showed that a high proportion of patients were receiving appropriate anticoagulation therapy. The numbers of patients with a long-term indication for OAC therapy that were not receiving oral anticoagulants, and without a long-term indication that were receiving OAC, were considerably lower than expected. Most patients take coumarins, and the quality of OAC control is reasonably high.
kurz und kn@pp news : Nr. 32
(2014)
Background: IL28B gene polymorphism is the best baseline predictor of response to interferon alfa-based antiviral therapies in chronic hepatitis C. Recently, a new IFN-L4 polymorphism was identified as first potential functional variant for induction of IL28B expression. Individualization of interferon alfa-based therapies based on a combination of IL28B/IFN-L4 polymorphisms may help to optimize virologic outcome and economic resources.
Methods: Optimization of treatment outcome prediction was assessed by combination of different IL28B and IFN-L4 polymorphisms in patients with chronic HCV genotype 1 (n = 385), 2/3 (n = 267), and 4 (n = 220) infection treated with pegylated interferon alfa (PEG-IFN) and ribavirin with (n = 79) or without telaprevir. Healthy people from Germany (n = 283) and Egypt (n = 96) served as controls.
Results: Frequencies of beneficial IL28B rs12979860 C/C genotypes were lower in HCV genotype 1/4 infected patients in comparison to controls (20–35% vs. 46–47%) this was also true for ss469415590 TT/TT (20–35% vs. 45–47%). Single interferon-lambda SNPs (rs12979860, rs8099917, ss469415590) correlated with sustained virologic response (SVR) in genotype 1, 3, and 4 infected patients while no association was observed for genotype 2. Interestingly, in genotype 3 infected patients, best SVR prediction was based on IFN-L4 genotype. Prediction of SVR with high accuracy (71–96%) was possible in genotype 1, 2, 3 and 4 infected patients who received PEG-IFN/ribavirin combination therapy by selection of beneficial IL28B rs12979860 C/C and/or ss469415590 TT/TT genotypes (p<0.001). For triple therapy with first generation protease inhibitors (PIs) (boceprevir, telaprevir) prediction of high SVR (90%) rates was based on the presence of at least one beneficial genotype of the 3 IFN-lambda SNPs.
Conclusion: IFN-L4 seems to be the best single predictor of SVR in genotype 3 infected patients. For optimized prediction of SVR by treatment with dual combination or first generation PI triple therapies, grouping of interferon-lambda haplotypes may be helpful with positive predictive values of 71–96%.
Background: In cystic fibrosis, highly variable glucose tolerance is suspected. However, no study provided within-patient coefficients of variation. The main objective of this short report was to evaluate within-patient variability of oral glucose tolerance.
Methods: In total, 4,643 standardized oral glucose tolerance tests of 1,128 cystic fibrosis patients (median age at first test: 15.5 [11.5; 21.5] years, 48.8% females) were studied. Patients included were clinically stable, non-pregnant, and had at least two oral glucose tolerance tests, with no prior lung transplantation or systemic steroid therapy. Transition frequency from any one test to the subsequent test was analyzed and within-patient coefficients of variation were calculated for fasting and two hour blood glucose values. All statistical analysis was implemented with SAS 9.4.
Results: A diabetic glucose tolerance was confirmed in 41.2% by the subsequent test. A regression to normal glucose tolerance at the subsequent test was observed in 21.7% and to impaired fasting glucose, impaired glucose tolerance or both in 15.2%, 12.0% or 9.9%. The average within-patient coefficient of variation for fasting blood glucose was 11.1% and for two hour blood glucose 25.3%.
Conclusion: In the cystic fibrosis patients studied, a highly variable glucose tolerance was observed. Compared to the general population, variability of two hour blood glucose was 1.5 to 1.8-fold higher.
Introduction: Curare is one of the best-examined neurotoxins of the world, which has empirically been used for centuries by American Indigenes. Research on curare has been performed much later, a global scientometric analysis on curare research or its derivates does not yet exist. This bibliometric analysis is part of the global NewQis-project and should illuminate both toxic and historic issues of research on curare.
Methods: The ISI Web of Science was searched for data covering 1900 to 2013 using a term which included as many original articles on curare as possible. 3,867 articles were found and analyzed for common bibliometric items such as the number of citations, language of the articles or the (modified) Hirsch-Index (h-index). Results are illustrated utilizing modern density equalizing map projections (DEMP) or beam diagrams.
Results: Most publications were located in North America and Europe. The USA has the highest number of publications as well as the highest h-index. The number of publications overall rose until the late 1990s and later decreased. Furthermore, sudden increases of research activity are ascribable to historic events, like the first use of curare as muscle relaxant during surgery.
Discussion: This scientometric analysis of curare research reflects several tendencies as previously seen in other bibliometric investigations, i.e. the scientific quality standard of North America and Europe. Research on curare decreased however, due to the declining attention towards this muscle relaxant. This work exemplifies also how scientometric methods can be used to illuminate historic circumstances immediately stimulating scientific research.
Introduction: To determine the esthetic outcome of implant-based reconstructions after autologous and allogeneic bone grafting.
Methods: From 2003 to 2009, 67 patients underwent alveolar ridge augmentation and were enrolled in the study, 41 meet the inclusion criteria and 31 agreed to take part in the study. Patients were 18-69 years old (mean: 49.3 ± 13.8 years), and predominantly female. Patients received bone block grafts either autologous (n = 48) (AUBB) or allografts (ABB) (n = 19). Implants were inserted 4-7 months (autografts) or 5-6 months (allografts) after bone grafting. The Pink Esthetic Score (PES) as well as radiographic and subjective assessments were employed for the outcome analysis. The PES was assessed twice within one month based on digital photographic images that were randomly rearranged between evaluations by three independent, experienced investigators.
Results: Across all observations and investigators, the average PES was 7.5 ± 2.6 without differences between implants inserted in auto- and allografted bone, respectively. Patients assessed the allograft procedures as less painful and would have repeated it more often. The intra-rater reliability was excellent (correlation coefficients 0.7-0.9). The inter-observer agreement was lower (correlation coefficients 0.6-0.8).
Conclusions: Bone grafting with ABB allografts yields equivalent results to autologous grafting, and patients appreciate the omission of bone harvesting. The PES is a reliable method but should be performed by the same individual.
Recent advances in understanding the mechanisms of nonsmall cell lung cancer (NSCLC) has led to the development of targeted treatments, including the reversible epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors gefitinib and erlotinib, and the irreversible ErbB family blocker afatinib. Several important activating EGFR mutations have now been identified, which correlate strongly with response to treatment with these agents. Multiple randomised controlled trials have confirmed the association between the presence of activating EGFR mutations and objective response to gefitinib, erlotinib and afatinib, thus demonstrating their superiority over platinum-based chemotherapy as first-line treatment for NSCLC patients with EGFR mutation-positive tumours, and resulting in approval of these agents for use in this setting. It can be tempting to compare outcome data across multiple clinical trials and agents; however, substantial differences in methodology between studies, including investigator versus independent assessment and differences in patient eligibility, makes such comparisons fraught with difficulty. This critical review provides an overview of the evolution of the methodology used in eight phase III trials investigating first-line targeted treatment of NSCLC, identifies key differences in methodology and reporting, and critically assesses how these differences should be taken into account when interpreting the findings from such trials.
Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare haematopoietic malignancy characterized by dismal prognosis and overall poor therapeutic response. Since the biology of BPDCN is barely understood, our study aims to shed light on the genetic make-up of these highly malignant tumors. Using targeted high-coverage massive parallel sequencing, we investigated 50 common cancer genes in 33 BPDCN samples. We detected point mutations in NRAS (27.3% of cases), ATM (21.2%), MET, KRAS, IDH2, KIT (9.1% each), APC and RB1 (6.1% each), as well as in VHL, BRAF, MLH1, TP53 and RET (3% each). Moreover, NRAS, KRAS and ATM mutations were found to be mutually exclusive and we observed recurrent mutations in NRAS, IDH2, APC and ATM. CDKN2A deletions were detected in 27.3% of the cases followed by deletions of RB1 (9.1%), PTEN and TP53 (3% each). The mutual exclusive distribution of some mutations may point to different subgroups of BPDCN whose biological significance remains to be explored.
Background: Birch pollen-allergic subjects produce polyclonal cross-reactive IgE antibodies that mediate pollen-associated food allergies. The major allergen Bet v 1 and its homologs in plant foods bind IgE in their native protein conformation. Information on location, number and clinical relevance of IgE epitopes is limited. We addressed the use of an allergen-related protein model to identify amino acids critical for IgE binding of PR-10 allergens.
Method: Norcoclaurine synthase (NCS) from meadow rue is structurally homologous to Bet v 1 but does not bind Bet v 1-reactive IgE. NCS was used as the template for epitope grafting. NCS variants were tested with sera from 70 birch pollen allergic subjects and with monoclonal antibody BV16 reported to compete with IgE binding to Bet v 1.
Results: We generated an NCS variant (Δ29NCSN57/I58E/D60N/V63P/D68K) harboring an IgE epitope of Bet v 1. Bet v 1-type protein folding of the NCS variant was evaluated by 1H-15N-HSQC NMR spectroscopy. BV16 bound the NCS variant and 71% (50/70 sera) of our study population showed significant IgE binding. We observed IgE and BV16 cross-reactivity to the epitope presented by the NCS variant in a subgroup of Bet v 1-related allergens. Moreover BV16 blocked IgE binding to the NCS variant. Antibody cross-reactivity depended on a defined orientation of amino acids within the Bet v 1-type conformation.
Conclusion: Our system allows the evaluation of patient-specific epitope profiles and will facilitate both the identification of clinically relevant epitopes as biomarkers and the monitoring of therapeutic outcomes to improve diagnosis, prognosis, and therapy of allergies caused by PR-10 proteins.