The role of fibroplast growth factor receptor 4 in colorectal cancer

In den letzten zehn Jahren haben die Fibroblasten Wachstumsfaktoren (FGF) und deren Rezeptoren (FGFR) in der Krebsforschung immer mehr an Bedeutung gewonnen, nicht zuletzt auf Grund ihrer besonderen Rolle für zelluläres Wachstum, Differenzierung und Migration. Sie sind während der Krebsentstehung häufig von Mutationen betroffen. Vor allem FGFR4, welcher zudem einen Polymorphismus in der transmembranen Domäne des Rezeptors (G388R) aufweist, ist an verschiedensten Krebserkrankungen beteiligt. Die R388 (FGFR4Arg) Form wird häufig mit erhöhtem Tumorrisiko, schnellerem Krankheitsverlauf und schlechteren Überlebenschancen in Verbindung gebracht. Da die Rolle des FGFR4 im Dickdarmkrebs bisher nicht ausreichend geklärt war, sollte in dieser Arbeit der Einfluss des FGFR4 und dessen G388R Polymorphismus auf das Kolorektalkarzinom erforscht werden. Unsere Daten belegen eine erhöhte Expression der FGFR4 mRNA in 25% der untersuchten humanen Dickdarmkarzinomgewebe. Zudem weisen Patienten mit einem oder zwei FGFR4Arg Allelen ein höheres Tumor-Staging mit vermehrter Wahrscheinlichkeit zur Metastasierung auf. Folglich wird das FGFR4Arg Allel mit erhöhter Tumor Invasion und Metastasierung in Zusammenhang gebracht, was sich in Zellkulturmodellen bestätigte. In drei verschiedenen Kolonkarzinom-Zelllinienmodellen stimulierte FGFR4Arg die Migration und hemmte gleichzeitig Zelladhäsion und Koloniebildung. Im Gegensatz dazu stimulierte FGFR4Gly sowohl das Wachstum von Kolonien aus dünnen Kulturen als auch das 3-dimensionale, anheftungs-unabhängige Wachstum in einer Agarmatrix. Auch im Tiermodell konnte FGFR4Gly mit schnellerem Tumorwachstum assoziiert werden, während FGFR4Arg Tumormetastasierung von subkutanen Transplantaten in die Lunge beschleunigte. Hemmung des FGFR4 über siRNA oder ein adenovirales dominant-negatives Konstrukt führten beide zu verminderter Viabilität, Migration und Koloniebildung der Kolonkarzinom-Zelllinen. Unabhängig vom Polymorphismus stimulierte eine erhöhte Expression von FGFR4 Überlebens-Signalwege über die Aktivierung von FRS2α. Die Ergebnisse dieser Arbeit identifizieren beide allelische Formen des FGFR4 als Onkogene, welchen in der klinischen Krebstherapie unbedingt Beachtung geschenkt werden sollte. Eine erhöhte Expression von FGFR4Arg stimuliert Zellmigration und erhöht somit die Tumor-Aggressivität in vivo, während die erhöhte Expression von FGFR4Gly malignes Zellwachstum in vitro und in vivo fördert.The interest in fibroblast growth factors (FGFs) and their receptors (FGFRs) in cancer research constantly increased over the last decade because of the crucial role they play in cell proliferation, differentiation, and migration. During tumorigenesis their expression and activity is frequently deregulated. Especially FGFR4 with its genetic polymorphism affecting the transmembrane domain of the receptor (G388R) is involved in a wide variety of malignancies. The R388 (FGFR4Arg) form is associated with increased tumor risk, progression, aggressiveness and decreased survival in various cancer types. In colorectal cancer (CRC) the role of FGFR4 is not well described to date. Therefore, it was the aim of the study to elucidate the impact of FGFR4 and especially the G388R polymorphism on CRC. Our data show an up-regulation of FGFR4 mRNA expression in 25% of CRC tissue specimen. Moreover, FGFR4Arg carriers had an increased risk for higher tumor stage at diagnosis and metastatic lesions than FGFR4-G388 (FGFR4Gly) homozygous patients suggesting a role for the FGFR4Arg allele in invasion and metastasis. In vitro data, using three different CRC cell lines with differing FGFR4 endogenous expression and genotype, displayed stimulated cell migration but decreased clonogenicity for FGFR4Arg whereas over-expression of FGFR4Gly had a stimulatory effect on clonogenicity and anchorage independent growth. In vivo FGFR4Gly enhanced local tumor growth, while FGFR4Arg stimulated metastasis from subcutaneous xenotransplants to the lung. FGFR4 siRNA mediated knock down and a dominant-negative adenoviral construct expressing dominant negative FGFR4 caused down-regulation of cell viability, migration and colony formation CRC cell lines. On the cellular level phosphorylation of FRS2α was increased by FGFR4 over-expression leading to activation of cell survival pathways independent of the genotype. Based on the results of this study both allelic forms of FGFR4 have to be regarded as oncogenes and relevant targets for therapy in CRC. While FGFR4Arg over-expression was correlated with higher tumor aggressiveness in vivo, mediated by up-regulation of cell migration, over-expression of FGFR4Gly stimulated malignant cell growth in vitro and enhanced local tumor growth in vivo

Alternative Splicing of Fibroblast Growth Factor Receptor IgIII Loops in Cancer

Alternative splicing of the IgIII loop of fibroblast growth factor receptors (FGFRs) 1–3 produces b- and c-variants of the receptors with distinctly different biological impact based on their distinct ligand-binding spectrum. Tissue-specific expression of these splice variants regulates interactions in embryonic development, tissue maintenance and repair, and cancer. Alterations in FGFR2 splicing are involved in epithelial mesenchymal transition that produces invasive, metastatic features during tumor progression. Recent research has elucidated regulatory factors that determine the splice choice both on the level of exogenous signaling events and on the RNA-protein interaction level. Moreover, methodology has been developed that will enable the in depth analysis of splicing events during tumorigenesis and provide further insight on the role of FGFR 1–3 IIIb and IIIc in the pathophysiology of various malignancies. This paper aims to summarize expression patterns in various tumor types and outlines possibilities for further analysis and application

N-acetylation and phosphorylation of Sec complex subunits in the ER membrane.

BACKGROUND: Covalent modifications of proteins provide a mechanism to control protein function. Here, we have investigated modifications of the heptameric Sec complex which is responsible for post-translational protein import into the endoplasmic reticulum (ER). It consists of the Sec61 complex (Sec61p, Sbh1p, Sss1p) which on its own mediates cotranslational protein import into the ER and the Sec63 complex (Sec63p, Sec62p, Sec71p, Sec72p). Little is known about the biogenesis and regulation of individual Sec complex subunits. RESULTS: We show that Sbh1p when it is part of the Sec61 complex is phosphorylated on T5 which is flanked by proline residues. The phosphorylation site is conserved in mammalian Sec61ß, but only partially in birds, and not in other vertebrates or unicellular eukaryotes, suggesting convergent evolution. Mutation of T5 to A did not affect the ability of mutant Sbh1p to complement the growth defect in a Δsbh1Δsbh2 strain, and did not result in a hypophosphorylated protein which shows that alternate sites can be used by the T5 kinase. A survey of yeast phosphoproteome data shows that Sbh1p can be phosphorylated on multiple sites which are organized in two patches, one at the N-terminus of its cytosolic domain, the other proximal to the transmembrane domain. Surprisingly, although N-acetylation has been shown to interfere with ER targeting, we found that both Sbh1p and Sec62p are cotranslationally N-acetylated by NatA, and N-acetyl-proteome data indicate that Sec61p is modified by the same enzyme. Mutation of the N-acetylation site, however, did not affect Sec62p function in posttranslational protein import into the ER. Disabling NatA resulted in growth retardation, but not in co- or posttranslational translocation defects or instability of Sec62p or Sbh1p. CONCLUSIONS: We conclude that N-acetylation of transmembrane and tail-anchored proteins does not interfere with their ER-targeting, and that Sbh1p phosphorylation on T5, which is not present in Sbh2p, plays a non-essential role specific to the Sec61 complex.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

Coronary Event Risk Test (CERT) as a Risk Predictor for the 10-Year Clinical Outcome of Patients with Peripheral Artery Disease

(1) Background: Ceramides are a new kind of lipid biomarker and have already been demonstrated to be valuable risk predictors in coronary patients. Patients with peripheral artery disease (PAD) are a population with a worse prognosis and higher mortality risk compared to coronary artery disease (CAD) patients. However, the value of ceramides for risk prediction in PAD patients is still vague, as addressed in the present study. (2)Methods: This observational study included 379 PAD patients. The primary endpoint was all-cause mortality at 10 years of follow-up. A set of ceramides was measured by LC-MS/MS and combined according to the Coronary Event Risk Test (CERT) score, which categorizes patients into one of four risk groups (low risk, moderate risk, high risk, very high risk). (3) Results: Kaplan–Meier survival curves revealed that the overall survival of patients decreased with the increasing risk predicted by the four CERT categories, advancing from low risk to very high risk. Cox regression analysis demonstrated that each one-category increase resulted in a 35% rise in overall mortality risk (HR = 1.35 [1.16–1.58]). Multivariable adjustment, including, among others, age, LDL-cholesterol, type 2 diabetes, and statin treatment before the baseline, did not abrogate this significant association (HR = 1.22 [1.04–1.43]). Moreover, we found that the beneficial effect of statin treatment is significantly stronger in patients with a higher risk, according to CERT. (4) Conclusions: We conclude that the ceramide-based risk score CERT is a strong predictor of the 10-year mortality risk in patients with PAD.Peer reviewe

Evidence of infectious disease, trauma, disability and deficiency in skeletons from the 19th/20th century correctional facility and asylum «Realta» in Cazis, Switzerland.

As a reaction to widespread poverty, a system of coercive welfare developed in Switzerland during the 19th century. Poverty was often thought to result from an individual's misconduct rather than from structural, economic or political circumstances. People whose lifestyle deviated from the desired norm or who were unable to make a living for themselves were subjected to so-called administrative detention at institutions such as workhouses and poorhouses. The excavation of the cemetery of the correctional facility/workhouse and asylum «Realta» in Cazis offered the opportunity to gain insight into the living conditions of a marginalized group of people and to shed light on aspects of coercive welfare that have hardly been addressed in historical studies. A comprehensive study of pathological alterations was used to assess possible physical causes and effects of administrative detention. Skeletal samples from regular contemporaneous cemeteries provided data for the general population and thus allowed us to detect peculiarities in the «Realta» assemblage. Possible cases of Stickler Syndrome, microcephaly, congenital syphilis, endemic hypothyroidism and disabilities secondary to trauma may have been the reason for the affected individuals' institutionalisation. The high prevalence of tuberculosis was linked to the socioeconomic status and the living conditions at the facility. Several cases of scurvy and osteomalacia may have resulted from various risk factors such as poverty, alcoholism, mental illness or institutionalisation. The fracture rates, especially of ribs, were extremely high. A large proportion of the fractures were incompletely healed and most likely occurred during detention due to interpersonal violence. Underlying diseases further contributed to the high fracture rates. This first study on skeletons from an institution of administrative detention in Switzerland demonstrated how pre-existing health conditions and the socioeconomic background contributed to the chance of being detained, and how detention led to further deterioration of health

Computational stereo camera system with programmable control loop

Stereoscopic 3D has gained significant importance in the entertainment industry. However, production of high quality stereoscopic content is still a challenging art that requires mastering the complex interplay of human perception, 3D display properties, and artistic intent. In this paper, we present a computational stereo camera system that closes the control loop from capture and analysis to automatic adjustment of physical parameters. Intuitive interaction metaphors are developed that replace cumbersome handling of rig parameters using a touch screen interface with 3D visualization. Our system is designed to make stereoscopic 3D production as easy, intuitive, flexible, and reliable as possible. Captured signals are processed and analyzed in real-time on a stream processor. Stereoscopy and user settings define programmable control functionalities, which are executed in real-time on a control processor. Computational power and flexibility is enabled by a dedicated software and hardware architecture. We show that even traditionally difficult shots can be easily captured using our system. © 2011, ACM. All rights reserved