Universitätspublikationen
Refine
Year of publication
- 2021 (852)
- 2020 (635)
- 2019 (514)
- 2022 (460)
- 2018 (454)
- 2017 (324)
- 2016 (289)
- 2013 (246)
- 2014 (227)
- 2012 (216)
- 2015 (213)
- 2023 (163)
- 2011 (126)
- 2010 (104)
- 2024 (59)
- 2009 (48)
- 2008 (37)
- 2004 (21)
- 2007 (21)
- 2006 (18)
- 2001 (15)
- 1998 (14)
- 2002 (14)
- 2003 (14)
- 2005 (11)
- 2000 (10)
- 1999 (6)
- 1997 (5)
- 1913 (4)
- 1992 (3)
- 1975 (2)
- 1981 (2)
- 1985 (2)
- 1990 (2)
- 1991 (2)
- 1890 (1)
- 1897 (1)
- 1899 (1)
- 1901 (1)
- 1906 (1)
- 1908 (1)
- 1911 (1)
- 1918 (1)
- 1922 (1)
- 1923 (1)
- 1939 (1)
- 1951 (1)
- 1961 (1)
- 1963 (1)
- 1977 (1)
- 1982 (1)
- 1983 (1)
- 1984 (1)
- 1989 (1)
- 1993 (1)
- 1994 (1)
- 1995 (1)
- 1996 (1)
Document Type
- Article (4772)
- Preprint (174)
- Doctoral Thesis (102)
- Conference Proceeding (75)
- Part of Periodical (12)
- Part of a Book (8)
- Book (7)
- Review (4)
- Report (1)
- Working Paper (1)
Language
- English (5156) (remove)
Has Fulltext
- yes (5156)
Keywords
- inflammation (80)
- COVID-19 (57)
- SARS-CoV-2 (48)
- glioblastoma (38)
- apoptosis (37)
- cancer (37)
- Inflammation (34)
- autophagy (29)
- prostate cancer (29)
- breast cancer (27)
Institute
- Medizin (5156) (remove)
The objective of this pilot clinical study was to assess the safety, technical feasibility, pharmacokinetic (PK) profile and tumour response of DC Bead™ with irinotecan (DEBIRI™) delivered by intra-arterial embolisation for the treatment of metastatic colorectal cancer. Eleven patients with unresectable liver metastases from CRC, tumour burden <30% of liver volume, adequate haematological, liver and renal function, performance status of <2 were included in this study. Patients received up to 4 sessions of TACE with DEBIRI at 3-week intervals. Feasibility of the procedure, safety and tumour response were assessed after each cycle. PK was measured after the first cycle. Patients were followed up to 24 weeks. Only mild to moderate adverse events were observed. DEBIRI is a technically feasibile procedure; no technical complications were observed. Average Cmax for irinotecan and SN-38 was 194 ng/ml and 16.7 ng/ml, respectively, with average t½ of 4.6 h and 12.4 h following administration of DEBIRI. Best overall response during the study showed disease control in 9 patients (2 patients with partial response and 7 with stable disease, overall response rate of 18%). Our study shows that transarterial chemoembolisation with irinotecan-loaded DC beads (DEBIRI) is safe, technically feasible and effective with a good PK profile.
Understanding causal relationships, or effective connectivity, between parts of the brain is of utmost importance because a large part of the brain’s activity is thought to be internally generated and, hence, quantifying stimulus response relationships alone does not fully describe brain dynamics. Past efforts to determine effective connectivity mostly relied on model based approaches such as Granger causality or dynamic causal modeling. Transfer entropy (TE) is an alternative measure of effective connectivity based on information theory. TE does not require a model of the interaction and is inherently non-linear. We investigated the applicability of TE as a metric in a test for effective connectivity to electrophysiological data based on simulations and magnetoencephalography (MEG) recordings in a simple motor task. In particular, we demonstrate that TE improved the detectability of effective connectivity for non-linear interactions, and for sensor level MEG signals where linear methods are hampered by signal-cross-talk due to volume conduction.
Purpose: Student circus artists train as both artists and athletes with their bodies holding the key to professional success. The daily training load of student circus artists is often associated with maximum physical and psychological stress with injuries posing a threat to a potential professional career. The purpose of this study is the differentiated analysis and evaluation of work accidents in order to initiate the development of injury preventive programs.
Methods: The 17 years of data were obtained from standardized anonymous work accident records of the Berlin State Accident Insurance (UKB) as well as a State Artist Educational School (n = 169, Male: 70; Female: 99) from student artists. Evaluation and descriptive statistics were conducted with Excel 2007 and PASW Statistics 18.
Results: The injury risk seems to be relatively low (0.3 injuries/1000h). There are gender specific differences as to the location of injuries. Only 7% of the accidents demand a break of more than 3 days. Injury patterns vary depending on the activity and the employment of props/equipment. 75.2% of work accidents have multifactorial and 24.8% exogenous causes.
Conclusions: Because physical fitness is all important in the circus arts there are numerous options for injury prevention programs that should be realized subject to gender-specific differences. Follow-ups on chronic complaints and a more individual approach are indispensable due to the very specific activities in the circus arts.
Background: The incidence of pulmonary failure in trauma patients is considered to be influenced by several factors such as liver injury. We intended to assess the association of various potential predictors of pulmonary failure following thoracic trauma and liver injury.
Methods: Records of 12,585 trauma patients documented in the TraumaRegister DGU® of the German Trauma Society were analyzed regarding the potential impact of concomitant liver injury on the incidence of pulmonary failure using uni- and multivariate analyses. Pulmonary failure was defined as pulmonary failure of ≥ 3 SOFA-score points for at least two days. Patients were subdivided according to their injury pattern into four groups: group 1: AIS thorax < 3; AIS liver < 3; group 2: AIS thorax ≥ 3; AIS liver < 3; group 3: AIS thorax < 3; AIS liver ≥ 3 and group 4: AIS thorax ≥ 3; AIS liver ≥ 3.
Results: Overall, 2643 (21%) developed pulmonary failure, 12% (n= 642) in group 1, 26% (n= 697) in group 2, 16% (n= 30) in group 3, and 36% (n= 188) in group 4. Factors independently associated with pulmonary failure included relevant lung injury, pre-existing medical conditions (PMC), sex, transfusion of more than 10 units of packed red blood cells (PRBC), Glasgow Coma Scale (GCS) ≤ 8, and the ISS. However, liver injury was not associated with an increased risk of pulmonary failure following severe trauma in our setting.
Conclusions: Specific factors, but not liver injury, were associated with an increased risk of pulmonary failure following trauma. Trauma surgeons should be aware of these factors for optimized intensive care treatment.
In previous work we have documented the nuclear translocation of endothelial NOS (eNOS) and its participation in combinatorial complexes with Estrogen Receptor Beta (ERβ) and Hypoxia Inducible Factors (HIFs) that determine localized chromatin remodeling in response to estrogen (E2) and hypoxia stimuli, resulting in transcriptional regulation of genes associated with adverse prognosis in prostate cancer (PCa). To explore the role of nuclear eNOS in the acquisition of aggressive phenotype in PCa, we performed ChIP-Sequencing on chromatin-associated eNOS from cells from a primary tumor with poor outcome and from metastatic LNCaP cells. We found that: 1. the eNOS-bound regions (peaks) are widely distributed across the genome encompassing multiple transcription factors binding sites, including Estrogen Response Elements. 2. E2 increased the number of peaks, indicating hormone-dependent eNOS re-localization. 3. Peak distribution was similar with/without E2 with ≈ 55% of them in extragenic DNA regions and an intriguing involvement of the 5′ domain of several miRs deregulated in PCa. Numerous potentially novel eNOS-targeted genes have been identified suggesting that eNOS participates in the regulation of large gene sets. The parallel finding of downregulation of a cluster of miRs, including miR-34a, in PCa cells associated with poor outcome led us to unveil a molecular link between eNOS and SIRT1, an epigenetic regulator of aging and tumorigenicity, negatively regulated by miR-34a and in turn activating eNOS. E2 potentiates miR-34a downregulation thus enhancing SIRT1 expression, depicting a novel eNOS/SIRT1 interplay fine-tuned by E2-activated ER signaling, and suggesting that eNOS may play an important role in aggressive PCa.
Introduction: Vasospastic brain infarction is a devastating complication of aneurysmal subarachnoid hemorrhage (SAH). Using a probe for invasive monitoring of brain tissue oxygenation or blood flow is highly focal and may miss the site of cerebral vasospasm (CVS). Probe placement is based on the assumption that the spasm will occur either at the dependent vessel territory of the parent artery of the ruptured aneurysm or at the artery exposed to the focal thick blood clot. We investigated the likelihood of a focal monitoring sensor being placed in vasospasm or infarction territory on a hypothetical basis.
Methods: From our database we retrospectively selected consecutive SAH patients with angiographically proven (day 7–14) severe CVS (narrowing of vessel lumen >50%). Depending on the aneurysm location we applied a standard protocol of probe placement to detect the most probable site of severe CVS or infarction. We analyzed whether the placement was congruent with existing CVS/infarction.
Results: We analyzed 100 patients after SAH caused by aneurysms located in the following locations: MCA (n = 14), ICA (n = 30), A1CA (n = 4), AcoA or A2CA (n = 33), and VBA (n = 19). Sensor location corresponded with CVS territory in 93% of MCA, 87% of ICA, 76% of AcoA or A2CA, but only 50% of A1CA and 42% of VBA aneurysms. The focal probe was located inside the infarction territory in 95% of ICA, 89% of MCA, 78% of ACoA or A2CA, 50% of A1CA and 23% of VBA aneurysms.
Conclusion: The probability that a single focal probe will be situated in the territory of severe CVS and infarction varies. It seems to be reasonably accurate for MCA and ICA aneurysms, but not for ACA or VBA aneurysms.
Meeting Abstract : Gesellschaft für Arzneimittelanwendungsforschung und Arzneimittelepidemiologie e.V. (GAA). 17. Jahrestagung der Gesellschaft für Arzneimittelanwendungsforschung und Arzneimittelepidemiologie. Osnabrück, 25.-26.11.2010.
ntroduction: Several drugs require dose adjustment in patients with impaired renal function, which however, often goes undetected. Serum creatinine may be normal in patients while renal function is already reduced. The estimated GFR (eGFR) allows a more precise evaluation of the renal function. This study was carried out in a group practice for family medicine, in Frankfurt/ Main, Germany. The exploration aimed at investigating if patients with renal insufficiency were recognised and if their prescriptions were appropriate in terms of dose adjustment or contra-indications.
Methods: In patients (>65yrs) with renal insufficiency (creatinine clearance <60 ml/min), their prescribed medication was retrospectively explored (Observation period 1.1.2008 to 1.4.2009). The Cockroft-Gault formula was used as estimate for the eGFR, using a creatinine value from the patient’s charts. In 90 patients, a second eGFR could be estimated from a second creatinine value obtained within 3-6 months. The recommended dose of each prescription in the SmPC (Fachinformation“) was compared to the dose that had been actually prescribed.
Results: Out of 232 consecutively patients >65 yrs, 102 had an eGFR <60 ml/min, 16 of these had an eGFR <30 ml/min. The eGFR was closely correlated (r2=0.81) with an independent second eGFR. Out of these 102 patients, 48 had a serum creatinine level within the normal range. Renal adjustment was required in 263 of a total of 613 prescriptions. 72 prescriptions in a total of 45 patients were not appropriately adjusted (32) or prescribed despite a contraindication (40). For chronic prescriptions, metformin, ramipril, enalapril, HCTZ, and spironolactone accounted for 70% of inappropriate dosing; the magnitude of misdosing was 1.5 to 4 fold (median 2). 9 temporary prescriptions (of a total of 60 prescriptions) in 8 patients were not adjusted (cefuroxim, cefpodoxim, levofloxacin). We could not prove that patients with normal serum creatinine had a higher rate of inappropriate dosing than those with already elevated creatinine.
Discussion and conclusion: In this GP practice, we have demonstrated a considerable prevalence of inappropriate dosing in patients with impaired renal function. It remains to be elucidated whether surveillance of appropriate dosing in renal impairment can be optimized e.g. with CPOE.
Introduction: Encouraged by the change in licensing regulations the practical professional skills in Germany received a higher priority and are taught in medical schools therefore increasingly. This created the need to standardize the process more and more. On the initiative of the German skills labs the German Medical Association Committee for practical skills was established and developed a competency-based catalogue of learning objectives, whose origin and structure is described here.
Goal of the catalogue is to define the practical skills in undergraduate medical education and to give the medical schools a rational planning basis for the necessary resources to teach them.
Methods: Building on already existing German catalogues of learning objectives a multi-iterative process of condensation was performed, which corresponds to the development of S1 guidelines, in order to get a broad professional and political support.
Results: 289 different practical learning goals were identified and assigned to twelve different organ systems with three overlapping areas to other fields of expertise and one area of across organ system skills. They were three depths and three different chronological dimensions assigned and the objectives were matched with the Swiss and the Austrian equivalent.
Discussion: This consensus statement may provide the German faculties with a basis for planning the teaching of practical skills and is an important step towards a national standard of medical learning objectives.
Looking ahead: The consensus statement may have a formative effect on the medical schools to teach practical skills and plan the resources accordingly.
Introduction: Recent data suggest that benefit from trastuzumab and chemotherapy might be related to expression of HER2 and estrogen receptor (ESR1). Therefore, we investigated HER2 and ESR1 mRNA levels in core biopsies of HER2-positive breast carcinomas from patients treated within the neoadjuvant GeparQuattro trial.
Methods: HER2 levels were centrally analyzed by immunohistochemistry (IHC), silver in-situ hybridization (SISH) and qRT-PCR in 217 pretherapeutic formalin-fixed, paraffin-embedded (FFPE) core biopsies. All tumors had been HER2-positive by local pathology and had been treated with neoadjuvant trastuzumab/ chemotherapy in GeparQuattro.
Results: Only 73% of the tumors (158 of 217) were centrally HER2-positive (cHER2-positive) by IHC/SISH, with cHER2-positive tumors showing a significantly higher pCR rate (46.8% vs. 20.3%, p<0.0005). HER2 status by qRT-PCR showed a concordance of 88.5% with the central IHC/SISH status, with a low pCR rate in those tumors that were HER2-negative by mRNA analysis (21.1% vs. 49.6%, p<0.0005). The level of HER2 mRNA expression was linked to response rate in ESR1-positive tumors, but not in ESR1-negative tumors. HER2 mRNA expression was significantly associated with pCR in the HER2-positive/ESR1-positive tumors (p=0.004), but not in HER2-positive/ESR1-negative tumors.
Conclusions: Only patients with cHER2-positive tumors - irrespective of the method used - have an increased pCR rate with trastuzumab plus chemotherapy. In patients with cHER2-negative tumors the pCR rate is comparable to the pCR rate in the non-trastuzumab treated HER-negative population. Response to trastuzumab is correlated to HER2 mRNA levels only in ESR1-positive tumors. This study adds further evidence to the different biology of both subsets within the HER2-positive group.
Background: Critical organ shortage results in the utilization of extended donor criteria (EDC) liver grafts. These marginal liver grafts are prone to increased ischemia reperfusion injury (IRI) which may contribute to deteriorated graft function and survival. Experimental data have shown that the calcineurin inhibitor tacrolimus exerts protective effects on hepatic IRI when applied intravenously or directly as a hepatic rinse. Therefore, the aim of the present study is to examine the effects of an ex vivo tacrolimus perfusion on IRI in transplantation of EDC liver grafts.
Methods/Design: The TOP-Study (tacrolimus organ perfusion) is a randomized multicenter trial comparing the ex vivo tacrolimus perfusion of marginal liver grafts with placebo. We hypothesize that a tacrolimus rinse reduces IRI, potentially improving organ survival following transplantation of EDC livers. The study includes livers with two or more EDC, according to Eurotransplant International Foundation’s definition of EDC livers. Prior to implantation, livers randomized to the treatment group are rinsed with tacrolimus at a concentration of 20 ng/ml in 1000 ml Custodiol solution and in the placebo group with Custodiol alone. The primary endpoint is the maximum serum alanine transamninase (ALT) level within the first 48 hours after surgery; however, the study design also includes a 1-year observation period following transplantation. The TOP-Study is an investigator-initiated trial sponsored by the University of Munich Hospital. Seven other German transplant centers are participating (Berlin, Frankfurt, Heidelberg, Mainz, Münster, Regensburg, Tübingen) and aim to include a total of 86 patients.
Discussion: Tacrolimus organ perfusion represents a promising strategy to reduce hepatic IRI following the transplantation of marginal liver grafts. This treatment may help to improve the function of EDC grafts and therefore safely expand the donor pool in light of critical organ shortage.
Trial register: EudraCT number: 2010-021333-31, ClinicalTrials.gov identifier: NCT01564095
Background: Castleman’s disease is a rare lymphoproliferative disorder. It typically presents as mediastinal masses and causes a wide range of clinical symptoms. Histologically, Castleman’s disease is classified as either a hyalinic vascular or plasma cell variant. The prognosis mainly depends on the histological type and broadly varies. We herein report our sonographic findings in a patient with Castleman’s disease, including gray-scale ultrasonography, color Doppler ultrasonography, and sonoelastography ultrasonography, which have not been previously reported in the literature. These findings allowed for a preoperative diagnosis and avoidance of overly aggressive therapy.
Case presentation: A 28-year-old European female patient with unicentric Castleman’s disease of hyalinic vascular type (HV) restricted to the axilla was referred to us because of a 4-month history of a painless, solitary mass located in the left axilla. The patient’s medical history was unremarkable.
Conclusion: Castleman’s disease is a pathologic entity of unknown etiology and pathogenesis. In this case report of unicentric HV-type CD, we demonstrate that typical sonographic findings can lead to a preoperative diagnosis of Castleman’s disease. Core needle biopsy usually allows for a final diagnosis and helps to avoid unnecessary operations and overtreatment.
Background: The introduction of fast-track treatment procedures following cardiac surgery has significantly shortened hospitalisation times in intensive care units (ICU). Readmission to intensive care units is generally considered a negative quality criterion. The aim of this retrospective study is to statistically analyse risk factors and predictors for re-admission to the ICU after a fast-track patient management program.
Methods: 229 operated patients (67 ± 11 years, 75% male, BMI 27 ± 3, 6/2010-5/2011) with use of extracorporeal circulation (70 ± 31 min aortic crossclamping, CABG 62%) were selected for a preoperative fast-track procedure (transfer on the day of surgery to an intermediate care (IMC) unit, stable circulatory conditions, extubated). A uni- and multivariate analysis were performed to identify independent predictors for re-admission to the ICU.
Results: Over the 11-month study period, 36% of all preoperatively declared fast-track patients could not be transferred to an IMC unit on the day of surgery (n = 77) or had to be readmitted to the ICU after the first postoperative day (n = 4). Readmission or ICU stay signifies a dramatic worsening of the patient outcome (mortality 0/10%, mean hospital stay 10.3 ± 2.5/16.5 ± 16.3, mean transfusion rate 1.4 ± 1,7/5.3 ± 9.1). Predicators for failure of the fast-track procedure are a preoperative ASA class > 3, NYHA class > III and an operation time >267 min ± 74. The significant risk factors for a major postoperative event (= low cardiac output and/or mortality and/or renal failure and/or re-thoracotomy and/or septic shock and/or wound healing disturbances and/or stroke) are a poor EF (OR 2.7 CI 95% 0.98-7.6) and the described ICU readmission (OR 0.14 CI95% 0.05-0.36).
Conclusion: Re-admission to the ICU or failure to transfer patients to the IMC is associated with a high loss of patient outcome. The ASA > 3, NYHA class > 3 and operation time >267 minutes are independent predictors of fast track protocol failure.
Blood levels of Glial Fibrillary Acidic Protein (GFAP) in patients with neurological diseases
(2013)
Background and Purpose: The brain-specific astroglial protein GFAP is a blood biomarker candidate indicative of intracerebral hemorrhage in patients with symptoms suspicious of acute stroke. Comparably little, however, is known about GFAP release in other neurological disorders. In order to identify potential “specificity gaps” of a future GFAP test used to diagnose intracerebral hemorrhage, we measured GFAP in the blood of a large and rather unselected collective of patients with neurological diseases.
Methods: Within a one-year period, we randomly selected in-patients of our university hospital for study inclusion. Patients with ischemic stroke, transient ischemic attack and intracerebral hemorrhage were excluded. Primary endpoint was the ICD-10 coded diagnosis reached at discharge. During hospital stay, blood was collected, and GFAP plasma levels were determined using an advanced prototype immunoassay at Roche Diagnostics.
Results: A total of 331 patients were included, covering a broad spectrum of neurological diseases. GFAP levels were low in the vast majority of patients, with 98.5% of cases lying below the cut-off that was previously defined for the differentiation of intracerebral hemorrhage and ischemic stroke. No diagnosis or group of diagnoses was identified that showed consistently increased GFAP values. No association with age and sex was found.
Conclusion: Most acute and chronic neurological diseases, including typical stroke mimics, are not associated with detectable GFAP levels in the bloodstream. Our findings underline the hypothesis that rapid astroglial destruction as in acute intracerebral hemorrhage is mandatory for GFAP increase. A future GFAP blood test applied to identify patients with intracerebral hemorrhage is likely to have a high specificity.
Background: In a previous analysis (Int J Radiat Oncol Biol Phys 70:828-835,2010), we assessed whether an adjuvant supplementation with selenium (Se) improves Se status and reduces the radiation-induced side-effects of patients treated by adjuvant radiotherapy (RT) for cervical and uterine cancer. Now, a potential relation between the planning target volume (PTV) of the RT and the Se effect concerning radiation induced diarrhoea was evaluated in detail.
Methods: Whole blood Se concentrations had been measured in patients with cervical (n=11) and uterine cancer (n=70) after surgical treatment, during, and at the end of RT. Patients with initial Se concentrations of less than 84 μg/l were categorized as Se-deficient and randomized before RT to receive Se (as sodium selenite) per os on the days of RT, or to receive no supplement during RT. Diarrhoea was graded according to the Common Toxicity Criteria system (CTC, Version 2a). The evaluation of the PTV of the RT was ascertained with the help of a specialised computer-assisted treatment planning software used for radiation planning procedure.
Results: A total of 81 patients had been randomized for the initial supplementation study, 39 of which received Se [selenium group, SeG] and 42 serving as controls [control group, CG]. Mean Se levels did not differ between SeG and CG upon study initiation, but were significantly higher in the SeG compared to the CG at the end of RT. The actuarial incidence of at least CTC 2 radiation induced diarrhoea in the SeG was 20.5% compared to 44.5% in the CG (p=0.04). The median PTV in both groups was 1302 ml (916–4608). With a PTV of <= 1302 ml (n=41) the actuarial incidence of at least CTC 2 diarrhoea in the SeG was 22.3% (4 of 18 patients) compared to 34.8% (8 of 23 patients) in the CG (p=0.50). In patients with a PTV of > 1302 ml (n=40) the actuarial incidence of at least CTC 2 diarrhoea in the SeG was 19.1% (4 of 21 patients) versus 52.6% (10 of 19 patients) in the CG (p=0.046).
Conclusions: Se supplementation during RT was effective to improve blood Se status in Se-deficient cervical and uterine cancer patients, and reduces episodes and severity of RT-induced diarrhoea. This effect was most pronounced and significant in patients with large PTV (> 1302 ml).
Current theories of the pathophysiology of schizophrenia have focused on abnormal temporal coordination of neural activity. Oscillations in the gamma-band range (>25 Hz) are of particular interest as they establish synchronization with great precision in local cortical networks. However, the contribution of high gamma (>60 Hz) oscillations toward the pathophysiology is less established. To address this issue, we recorded magnetoencephalographic (MEG) data from 16 medicated patients with chronic schizophrenia and 16 controls during the perception of Mooney faces. MEG data were analysed in the 25–150 Hz frequency range. Patients showed elevated reaction times and reduced detection rates during the perception of upright Mooney faces while responses to inverted stimuli were intact. Impaired processing of Mooney faces in schizophrenia patients was accompanied by a pronounced reduction in spectral power between 60–120 Hz (effect size: d = 1.26) which was correlated with disorganized symptoms (r = −0.72). Our findings demonstrate that deficits in high gamma-band oscillations as measured by MEG are a sensitive marker for aberrant cortical functioning in schizophrenia, suggesting an important aspect of the pathophysiology of the disorder.
As inhibitor of apoptosis (IAP) proteins can regulate additional signaling pathways beyond apoptosis, we investigated the effect of the second mitochondrial activator of caspases (Smac) mimetic BV6, which antagonizes IAP proteins, on non-apoptotic functions in glioblastoma (GBM). Here, we identify non-canonical nuclear factor-κB (NF-κB) signaling and a tumor necrosis factor-α (TNFα)/TNF receptor 1 (TNFR1) autocrine/paracrine loop as critical mediators of BV6-stimulated migration and invasion of GBM cells. In addition to GBM cell lines, BV6 triggers cell elongation, migration and invasion in primary, patient-derived GBM cells at non-toxic concentrations, which do not affect cell viability or proliferation, and also increases infiltrative tumor growth in vivo underscoring the relevance of these findings. Molecular studies reveal that BV6 causes rapid degradation of cellular IAP proteins, accumulation of NIK, processing of p100 to p52, translocation of p52 into the nucleus, increased NF-κB DNA binding and enhanced NF-κB transcriptional activity. Electrophoretic mobility shift assay supershift shows that the NF-κB DNA-binding subunits consist of p50, p52 and RelB further confirming the activation of the non-canonical NF-κB pathway. BV6-stimulated NF-κB activation leads to elevated mRNA levels of TNFα and additional NF-κB target genes involved in migration (i.e., interleukin 8, monocyte chemoattractant protein 1, CXC chemokine receptor 4) and invasion (i.e., matrix metalloproteinase-9). Importantly, inhibition of NF-κB by overexpression of dominant-negative IκBα superrepressor prevents the BV6-stimulated cell elongation, migration and invasion. Similarly, specific inhibition of non-canonical NF-κB signaling by RNA interference-mediated silencing of NIK suppresses the BV6-induced cell elongation, migration and invasion as well as upregulation of NF-κB target genes. Intriguingly, pharmacological or genetic inhibition of the BV6-stimulated TNFα autocrine/paracrine loop by the TNFα-blocking antibody Enbrel or by knockdown of TNFR1 abrogates BV6-induced cell elongation, migration and invasion. By demonstrating that the Smac mimetic BV6 at non-toxic concentrations promotes migration and invasion of GBM cells via non-canonical NF-κB signaling, our findings have important implications for the use of Smac mimetics as cancer therapeutics.
This study indicates that embryonic stem cells [ESCs] cultured with retinoic acid and activin A significantly upregulate the miRNA let-7e. This specific miRNA modulates the Wnt pathway and the expression of early nephrogenic markers under these differentiation conditions. The differentiation markers WT1, Pax2 and Wnt4 were downregulated when miRNA let-7e was silenced, thus indicating the role of miRNA let-7e in the differentiation process. PKCβ, GSK3β phosphorylation (GSK3βP) and β-catenin expression was reduced in differentiated cells and reversed by miRNA let-7e silencing. Addition of a PKCβ inhibitor to the miRNA let-7e silenced cells abolished let-7e-derived effects in differentiation markers, and reversed the increase in GSK3βP and β-catenin, thus indicating that miRNA let-7e is involved in differentiation via the modulation of GSK3β phosphorylation and β-catenin production.
Orthotopic bladder cancer xenografts are essential for testing novel therapies and molecular manipulations of cell lines in vivo. Current xenografts rely on tumor cell inoculation by intravesical instillation or direct injection into the bladder wall. Instillation is limited by the lack of cell lines that are tumorigenic when delivered in this manner. The invasive model inflicts morbidity on the mice by the need for laparotomy and mobilization of the bladder. Furthermore this procedure is complex and time-consuming. Three bladder cancer cell lines (UM-UC1, UM-UC3, UM-UC13) were inoculated into 50 athymic nude mice by percutaneous injection under ultrasound guidance. PBS was first injected between the muscle wall and the mucosa to separate these layers, and tumor cells were subsequently injected into this space. Bioluminescence and ultrasound were used to monitor tumor growth. Contrast-enhanced ultrasound was used to study changes in tumor perfusion after systemic gemcitabine/cisplatin treatment. To demonstrate proof of principle that therapeutic agents can be injected into established xenografts under ultrasound guidance, oncolytic virus (VSV) was injected into UM-UC3 tumors. Xenograft tissue was harvested for immunohistochemistry after 23–37 days. Percutaneous injection of tumor cells into the bladder wall was performed efficiently (mean time: 5.7 min) and without complications in all 50 animals. Ultrasound and bioluminescence confirmed presence of tumor in the anterior bladder wall in all animals 3 days later. The average tumor volumes increased steadily over the study period. UM-UC13 tumors showed a marked decrease in volume and perfusion after chemotherapy. Immunohistochemical staining for VSV-G demonstrated virus uptake in all UM-UC3 tumors after intratumoral injection. We have developed a novel method for creating orthotopic bladder cancer xenograft in a minimally invasive fashion. In our hands this has replaced the traditional model requiring laparotomy, because this model is more time efficient, more precise and associated with less morbidity for the mice.
Natural killer (NK) cells are highly specialized effectors of the innate immune system that hold promise for adoptive cancer immunotherapy. Their cell killing activity is primarily mediated by the pro-apoptotic serine protease granzyme B (GrB), which enters targets cells with the help of the pore-forming protein perforin. We investigated expression of a chimeric GrB fusion protein in NK cells as a means to augment their antitumoral activity. For selective targeting to tumor cells, we fused the epidermal growth factor receptor (EGFR) peptide ligand transforming growth factor α (TGFα) to human pre-pro-GrB. Established human NKL natural killer cells transduced with a lentiviral vector expressed this GrB-TGFα (GrB-T) molecule in amounts comparable to endogenous wildtype GrB. Activation of the genetically modified NK cells by cognate target cells resulted in the release of GrB-T together with endogenous granzymes and perforin, which augmented the effector cells' natural cytotoxicity against NK-sensitive tumor cells. Likewise, GrB-T was released into the extracellular space upon induction of degranulation with PMA and ionomycin. Secreted GrB-T fusion protein displayed specific binding to EGFR-overexpressing tumor cells, enzymatic activity, and selective target cell killing in the presence of an endosomolytic activity. Our data demonstrate that ectopic expression of a targeted GrB fusion protein in NK cells is feasible and can enhance antitumoral activity of the effector cells.
Neuronal activity differs between wakefulness and sleep states. In contrast, an attractor state, called self-organized critical (SOC), was proposed to govern brain dynamics because it allows for optimal information coding. But is the human brain SOC for each vigilance state despite the variations in neuronal dynamics? We characterized neuronal avalanches – spatiotemporal waves of enhanced activity - from dense intracranial depth recordings in humans. We showed that avalanche distributions closely follow a power law – the hallmark feature of SOC - for each vigilance state. However, avalanches clearly differ with vigilance states: slow wave sleep (SWS) shows large avalanches, wakefulness intermediate, and rapid eye movement (REM) sleep small ones. Our SOC model, together with the data, suggested first that the differences are mediated by global but tiny changes in synaptic strength, and second, that the changes with vigilance states reflect small deviations from criticality to the subcritical regime, implying that the human brain does not operate at criticality proper but close to SOC. Independent of criticality, the analysis confirms that SWS shows increased correlations between cortical areas, and reveals that REM sleep shows more fragmented cortical dynamics.