German Cancer Consortium DKTK

Berlin, Germany

German Cancer Consortium DKTK

Berlin, Germany
Time filter
Source Type

Farin H.F.,University Utrecht | Farin H.F.,Institute for Tumor Biology and Experimental Therapy | Farin H.F.,German Cancer Research Center | Jordens I.,University Utrecht | And 11 more authors.
Nature | Year: 2016

Mammalian Wnt proteins are believed to act as short-range signals1-4, yet have not been previously visualized in vivo. Selfrenewal, proliferation and differentiation are coordinated along a putative Wnt gradient in the intestinal crypt5. Wnt3 is produced specifically by Paneth cells6,7. Here we have generated an epitopetagged, functional Wnt3 knock-in allele. Wnt3 covers basolateral membranes of neighbouring stem cells. In intestinal organoids, Wnt3-transfer involves direct contact between Paneth cells and stem cells. Plasma membrane localization requires surface expression of Frizzled receptors, which in turn is regulated by the transmembrane E3 ligases Rnf43/Znrf3 and their antagonists Lgr4-5/R-spondin. By manipulating Wnt3 secretion and by arresting stem-cell proliferation, we demonstrate that Wnt3 mainly travels away from its source in a cell-bound manner through cell division, and not through diffusion. We conclude that stem-cell membranes constitute a reservoir for Wnt proteins, while Frizzled receptor turnover and 'plasma membrane dilution' through cell division shape the epithelial Wnt3 gradient. © 2016 Macmillan Publishers Limited.

Van Allen E.M.,Dana-Farber Cancer Institute | Van Allen E.M.,The Broad Institute of MIT and Harvard | Miao D.,Dana-Farber Cancer Institute | Miao D.,The Broad Institute of MIT and Harvard | And 25 more authors.
Science | Year: 2015

Monoclonal antibodies directed against cytotoxic T lymphocyte-associated antigen-4 (CTLA-4), such as ipilimumab, yield considerable clinical benefit for patients with metastatic melanoma by inhibiting immune checkpoint activity, but clinical predictors of response to these therapies remain incompletely characterized. To investigate the roles of tumor-specific neoantigens and alterations in the tumor microenvironment in the response to ipilimumab, we analyzed whole exomes from pretreatment melanoma tumor biopsies and matching germline tissue samples from 110 patients. For 40 of these patients, we also obtained and analyzed transcriptome data from the pretreatment tumor samples. Overall mutational load, neoantigen load, and expression of cytolytic markers in the immune microenvironment were significantly associated with clinical benefit. However, no recurrent neoantigen peptide sequences predicted responder patient populations. Thus, detailed integrated molecular characterization of large patient cohorts may be needed to identify robust determinants of response and resistance to immune checkpoint inhibitors.

Louis D.N.,Harvard University | Perry A.,University of California at San Francisco | Reifenberger G.,Heinrich Heine University Düsseldorf | von Deimling A.,German Cancer Consortium DKTK | And 7 more authors.
Acta Neuropathologica | Year: 2016

The 2016 World Health Organization Classification of Tumors of the Central Nervous System is both a conceptual and practical advance over its 2007 predecessor. For the first time, the WHO classification of CNS tumors uses molecular parameters in addition to histology to define many tumor entities, thus formulating a concept for how CNS tumor diagnoses should be structured in the molecular era. As such, the 2016 CNS WHO presents major restructuring of the diffuse gliomas, medulloblastomas and other embryonal tumors, and incorporates new entities that are defined by both histology and molecular features, including glioblastoma, IDH-wildtype and glioblastoma, IDH-mutant; diffuse midline glioma, H3 K27M–mutant; RELA fusion–positive ependymoma; medulloblastoma, WNT-activated and medulloblastoma, SHH-activated; and embryonal tumour with multilayered rosettes, C19MC-altered. The 2016 edition has added newly recognized neoplasms, and has deleted some entities, variants and patterns that no longer have diagnostic and/or biological relevance. Other notable changes include the addition of brain invasion as a criterion for atypical meningioma and the introduction of a soft tissue-type grading system for the now combined entity of solitary fibrous tumor / hemangiopericytoma—a departure from the manner by which other CNS tumors are graded. Overall, it is hoped that the 2016 CNS WHO will facilitate clinical, experimental and epidemiological studies that will lead to improvements in the lives of patients with brain tumors. © 2016, Springer-Verlag Berlin Heidelberg.

Schulz M.D.,TU Munich | Atay C.,TU Munich | Heringer J.,TU Munich | Romrig F.K.,TU Munich | And 22 more authors.
Nature | Year: 2014

Several features common to a Western lifestyle, including obesity and low levels of physical activity, are known risk factors for gastrointestinal cancers1. There is substantial evidence suggesting that diet markedly affects the composition of the intestinal microbiota2.Moreover, there is now unequivocal evidence linking dysbiosis to cancer development3.However, the mechanisms by which high-fat diet (HFD)- mediated changes in the microbial community affect the severity of tumorigenes is in the gut remain to be determined. Here we demonstrate that an HFD promotes tumour progression in the small intestine of genetically susceptible, K-rasG12Dint, mice independently of obesity. HFD consumption, in conjunction with K-ras mutation, mediated a shift in the composition of the gut micro biota, and this shift was associated with a decrease in Paneth-cell-mediated antimicrobial host defence that compromised dendritic cell recruitment and MHC class II molecule presentation in the gut-associated lymphoid tissues. When butyrate was administered to HFD-fed K-rasG12Dint mice, dendritic cell recruitment in the gut-associated lymphoid tissues was normalized, and tumour progression was attenuated. Importantly, deficiency in MYD88, a sign alling adaptor for pattern recognition receptors and Toll-like receptors, blocked tumour progression. The transfer of faecal samples from HFD-fed mice with intestinal tumours to healthy adult K-rasG12Dintmice was sufficient to transmit disease in the absence of an HFD. Furthermore, treatment with antibiotics completely blocked HFD-induced tumour progression, suggesting that distinct shifts inthe microbiota have a pivotal role in aggravating disease. Collectively, these data underscore the importance of the reciprocal interaction between host and environmental factors in selecting a microbiota that favours carcinogenesis, and they suggest that tumorigenesis is transmissible among genetically predisposed individuals. © 2014 Macmillan Publishers Limited. All rights reserved.

Luo C.,German Cancer Research Center | Merz P.R.,German Cancer Research Center | Chen Y.,Max Planck Institute for Medical Research | Dickes E.,German Cancer Research Center | And 4 more authors.
Cancer Letters | Year: 2013

The microRNA miR-101 has been reported to be a tumor suppressor. Here we show that low expression of miR-101 is associated with poor survival in stage IV melanoma patients. We identified microphthalmia-associated transcription factor (MITF) as a direct target of miR-101. In melanoma cells, overexpression of miR-101 downregulated protein levels of MITF and a previously reported target protein, enhancer of zeste homolog 2 (EZH2). Functional assays showed that miR-101 suppressed invasion and proliferation - an outcome that could be phenocopied by siRNA knockdown of MITF and EZH2. Our data suggest that miR-101 might have a beneficial role in melanoma. © 2013 Elsevier Ireland Ltd.

Weide B.,University Hospital Freiburg | Weide B.,German Cancer Research Center | Martens A.,University of Tübingen | Zelba H.,University of Tübingen | And 13 more authors.
Clinical Cancer Research | Year: 2014

Purpose: To analyze the prognostic relevance and relative impact of circulating myeloid-derived suppressor cells (MDSC) and regulatory T cells (Treg) compared with functional tumor antigen-specific T cells in patients with melanoma with distant metastasis. Experimental Design: The percentage of CD14CD11bHLA-DR/low MDSCs, CD4CD25FoxP3 Tregs, and the presence of NY-ESO-1- or Melan-A-specific T cells was analyzed in 94 patients and validated in an additional cohort of 39 patients by flow cytometry. Univariate survival differences were calculated according to Kaplan-Meier and log-rank tests. Multivariate analyses were performed using Cox regression models. Results: NY-ESO-1-specific T cells, the M-category, and the frequency of MDSCs were associated with survival. The absence of NY-ESO-1-specific T cells and the M-category M1c independently increased the risk of death. In a second Cox model not considering results on antigen-specific T cells, a frequency of >11% MDSCs showed independent impact. Its association with survival was confirmed in the additional patient cohort. Median survival of patients with a lower frequency of MDSCs was 13 months versus 8 months for others (P < 0.001, combined cohorts). We observed a strong correlation between high levels of MDSCs and the absence of melanoma antigen-specific T cells implying a causal and clinically relevant interaction. No prognostic impact was observed for Tregs. Conclusions: Circulating CD14CD11bHLA-DR/low MDSCs have a negative impact on survival and inversely correlate with the presence of functional antigen-specific T cells in patients with advanced melanoma. Our findings provide a rationale to investigate MDSC-depleting strategies in the therapeutic setting especially in combination with vaccination or T-cell transfer approaches. © 2014 American Association for Cancer Research.

Gohlke B.O.,German Cancer Consortium DKTK | Preissner R.,Charité - Medical University of Berlin | Preissner S.,Charité - Medical University of Berlin
Nucleic Acids Research | Year: 2014

Pain is more than an unpleasant sensory experience associated with actual or potential tissue damage: it is the most common reason for physician consultation and often dramatically affects quality of life. The management of pain is often difficult and new targets are required for more effective and specific treatment. SuperPain ( is freely available database for pain-stimulating and pain-relieving compounds, which bind or potentially bind to ion channels that are involved in the transmission of pain signals to the central nervous system, such as TRPV1, TRPM8, TRPA1, TREK1, TRESK, hERG, ASIC, P2X and voltage-gated sodium channels. The database consists of ∼8700 ligands, which are characterized by experimentally measured binding affinities. Additionally, 100 000 putative ligands are included. Moreover, the database provides 3D structures of receptors and predicted ligand-binding poses. These binding poses and a structural classification scheme provide hints for the design of new analgesic compounds. A user-friendly graphical interface allows similarity searching, visualization of ligands docked into the receptor, etc. © 2013 The Author(s). Published by Oxford University Press.

Laubender R.P.,German Cancer Consortium DKTK | Laubender R.P.,Ludwig Maximilians University of Munich | Laubender R.P.,German Cancer Research Center | Bender R.,Institute for Quality and Efficiency in Health Care IQWiG | Bender R.,University of Cologne
Statistics in Medicine | Year: 2014

Recently, Laubender and Bender (Stat.Med.2010; 29: 851-859) applied the average risk difference (RD) approach to estimate adjusted RD and corresponding number needed to treat measures in the Cox proportional hazards model. We calculated standard errors and confidence intervals by using bootstrap techniques. In this paper, we develop asymptotic variance estimates of the adjusted RD measures and corresponding asymptotic confidence intervals within the counting process theory and evaluated them in a simulation study. We illustrate the use of the asymptotic confidence intervals by means of data of the Düsseldorf Obesity Mortality Study. © 2013 John Wiley & Sons, Ltd.

The RAS-RAF-MEK1/2-ERK1/2 pathway is a key signal transduction pathway in the cells. Critically, it remains constitutively active in approximately 30% of human cancers, having key roles in cancer development, maintenance and progression, while being responsible for poorer prognosis and drug resistance. Consequently, the inhibition of this pathway has been the subject of intense research for >25 years. The advent of better patient screening techniques has increasingly shown that upstream regulators like RAS and RAF remain persistently mutated in many cancer types. These gain-of-function mutations, such as KRAS-4BG12V/G13D/Q61K, NRASQ61L/Q61R or BRAFV600E, lead to tremendous increase in their activities, resulting in constitutively active extracellular signal–regulated kinase 1/2 (ERK1/2). They were not efficiently targeted by the first-generation inhibitors such as Lonafarnib or Sorafenib, which were essentially broad spectrum inhibitors targeting pan-RAS and pan-RAF, respectively. This triggered the development of the second-generation inhibitors selective against the mutated proteins. Second generation inhibitors such as Vemurafenib (Zelboraf) and Dabrafenib (Tafinlar) targeting BRAFV600E, Trametinib (Mekinist) targeting MEK1/2 and the first generation pan-RAF inhibitor Sorafenib (Nexavar) have already been approved for treating renal, hepatocellular, thyroid cancers and BRAFV600E/K harboring metastatic melanoma. Others against RAF and MEK1/2 are presently undergoing clinical trials. Their success would depend on the better understanding of the acquired resistance mechanisms to these drugs in the cancer cells and the identification of predictive biomarkers for the proper administration of suitable inhibitor(s).Oncogene advance online publication, 14 September 2015; doi:10.1038/onc.2015.329. © 2015 Macmillan Publishers Limited

Strebhardt K.,Goethe University Frankfurt | Becker S.,Goethe University Frankfurt | Matthess Y.,German Cancer Consortium DKTK
Expert Opinion on Drug Discovery | Year: 2015

The Polo-like kinase 1 (Plk1) plays a key role in regulating a broad spectrum of critical cell cycle events. Plk1 is a marker of cellular proliferation and has prognostic potential in different types of human tumors. In a series of preclinical studies, Plk1 has been validated as a cancer target. This prompted many pharmaceutical companies to develop small-molecule inhibitors targeting the classical ATP-binding site of Plk1 for anticancer drug development. Recently, FDA has granted a Breakthrough Therapy designation to the Plk inhibitor BI 6727 (volasertib), which provided a survival benefit for patients suffering from acute myeloid leukemia. Remarkably, a new generation of Plk1 inhibitors that target the second druggable domain of Plk1, the Polo-box domain, is currently being tested preclinically. Since various ATP-competitive compounds of Plk1 inhibit also the activities of Plk2 and Plk3, which act as tumor suppressors, the roles of closely related Plk-family members in cancer cells need to be considered carefully. In this article, the authors highlight recent insights into the biology of Plks in cancer cells and discuss the progress in the development of small-molecule Plk1 inhibitors. The authors believe that the greatest therapeutic benefit might come through leukemic cells that are in direct contact with the inhibitor in the blood stream. The identification of biomarkers and studies that document Plk activities in treated patients would also be beneficial to better understand the role of Plk inhibition in tumor development and anticancer therapy. © 2015 Informa UK, Ltd.

Loading German Cancer Consortium DKTK collaborators
Loading German Cancer Consortium DKTK collaborators