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1.
F1000Res ; 9: 1188, 2020.
Article in English | MEDLINE | ID: mdl-33149900

ABSTRACT

In academia, decisions on promotions are influenced by the citation impact of the works published by the candidates. The Medical Faculty of the University of Bern used a measure based on the journal impact factor (JIF) for this purpose: the JIF of the papers submitted for promotion should rank in the upper third of journals in the relevant discipline (JIF rank >0.66). The San Francisco Declaration on Research Assessment (DORA) aims to eliminate the use of journal-based metrics in academic promotion. We examined whether the JIF rank could be replaced with the relative citation ratio (RCR), an article-level measure of citation impact developed by the National Institutes of Health (NIH). An RCR percentile >0.66 corresponds to the upper third of citation impact of articles from NIH-sponsored research. We examined 1525 publications submitted by 64 candidates for academic promotion at University of Bern. There was only a moderate correlation between the JIF rank and RCR percentile (Pearson correlation coefficient 0.34, 95% CI 0.29-0.38). Among the 1,199 articles (78.6%) published in journals ranking >0.66 for the JIF, less than half (509, 42.5%) were in the upper third of the RCR percentile. Conversely, among the 326 articles published in journals ranking <0.66 regarding the JIF, 72 (22.1%) ranked in the upper third of the RCR percentile. Our study demonstrates that the rank of the JIF is a bad proxy measure for the actual citation impact of individual articles. The Medical Faculty of University of Bern has signed DORA and replaced the JIF rank with the RCR percentile to assess the citation impact of papers submitted for academic promotion.


Subject(s)
Academic Success , Universities , Benchmarking , Humans , Journal Impact Factor , Switzerland
2.
BJU Int ; 120(5B): E45-E51, 2017 11.
Article in English | MEDLINE | ID: mdl-27987524

ABSTRACT

OBJECTIVE: To conduct a central pathology review within a randomized clinical trial on salvage radiation therapy (RT) in the presence of biochemical recurrence after prostatectomy to assess whether this results in changes in histopathological prognostic factors, such as Gleason score. PATIENTS AND METHODS: A total of 350 patients were randomized and specimens from 279 patients (80%) were centrally reviewed by a dedicated genitourinary pathologist. Gleason score, tumour classification and resection margin status were reassessed and compared with the results of local pathology review. Agreement was assessed using contingency tables and Cohen's kappa coefficient. The association between other histopathological features (e.g. largest diameter of carcinoma) and rapid biochemical progression (up to 6 months after salvage RT) was also investigated. RESULTS: There was good concordance between central and local pathology review for seminal vesicle invasion (pT3b: 91%; κ = 0.95 [95% confidence interval {CI} 0.89, 1.00]), extraprostatic extension (pT3a/b: 94%; κ = 0.82 [95% CI 0.75, 0.89]) and positive surgical margin (PSM) status (87%; κ = 0.7 [95% CI 0.62, 0.79]). The rate of agreement was lower for Gleason score (78%; κ = 0.61 [95% CI 0.52, 0.70]). The median (range) largest diameter of carcinoma was 16 (3-38) mm. A total of 49 patients (18%) experienced rapid biochemical progression after salvage RT. Largest diameter of carcinoma (odds ratio [OR] 2.04 [95% CI 1.30, 3.20]; P = 0.002), resection margin status (OR 0.36 [95% CI 0.18, 0.72]; P = 0.004) and Gleason score (OR 1.55 [95% CI 1.00, 2.42]; P = 0.05) remained associated with rapid progression after salvage RT after backward selection. CONCLUSION: The results of the central pathology analyses showed concordance between central and local pathology review with regard to seminal vesicle invasion, extraprostatic extension and PSM status, but a lower rate of agreement for Gleason score. Largest diameter of carcinoma was found to be a potential prognostic factor for rapid biochemical progression after salvage RT.


Subject(s)
Prostatectomy , Prostatic Neoplasms/pathology , Aged , Clinical Trials, Phase III as Topic , Humans , Immunohistochemistry , In Situ Hybridization, Fluorescence , Male , Middle Aged , Neoplasm Grading , Neoplasm Recurrence, Local/pathology , Predictive Value of Tests , Prostate-Specific Antigen , Radiotherapy, Adjuvant , Random Allocation , Randomized Controlled Trials as Topic , Retrospective Studies , Salvage Therapy , Treatment Outcome
3.
J Clin Oncol ; 33(35): 4158-66, 2015 Dec 10.
Article in English | MEDLINE | ID: mdl-26527774

ABSTRACT

PURPOSE: Patients with biochemical failure (BF) after radical prostatectomy may benefit from dose-intensified salvage radiation therapy (SRT) of the prostate bed. We performed a randomized phase III trial assessing dose intensification. PATIENTS AND METHODS: Patients with BF but without evidence of macroscopic disease were randomly assigned to either 64 or 70 Gy. Three-dimensional conformal radiation therapy or intensity-modulated radiation therapy/rotational techniques were used. The primary end point was freedom from BF. Secondary end points were acute toxicity according to the National Cancer Institute Common Terminology Criteria for Adverse Events (version 4.0) and quality of life (QoL) according to the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaires C30 and PR25. RESULTS: Three hundred fifty patients were enrolled between February 2011 and April 2014. Three patients withdrew informed consent, and three patients were not eligible, resulting in 344 patients age 48 to 75 years in the safety population. Thirty patients (8.7%) had grade 2 and two patients (0.6%) had grade 3 genitourinary (GU) baseline symptoms. Acute grade 2 and 3 GU toxicity was observed in 22 patients (13.0%) and one patient (0.6%), respectively, with 64 Gy and in 29 patients (16.6%) and three patients (1.7%), respectively, with 70 Gy (P = .2). Baseline grade 2 GI toxicity was observed in one patient (0.6%). Acute grade 2 and 3 GI toxicity was observed in 27 patients (16.0%) and one patient (0.6%), respectively, with 64 Gy, and in 27 patients (15.4%) and four patients (2.3%), respectively, with 70 Gy (P = .8). Changes in early QoL were minor. Patients receiving 70 Gy reported a more pronounced and clinically relevant worsening in urinary symptoms (mean difference in change score between arms, 3.6; P = .02). CONCLUSION: Dose-intensified SRT was associated with low rates of acute grade 2 and 3 GU and GI toxicity. The impact of dose-intensified SRT on QoL was minor, except for a significantly greater worsening in urinary symptoms.


Subject(s)
Biomarkers, Tumor/blood , Neoplasm Recurrence, Local/blood , Neoplasm Recurrence, Local/radiotherapy , Prostate-Specific Antigen/blood , Prostatectomy , Prostatic Neoplasms/radiotherapy , Radiotherapy, Conformal/adverse effects , Salvage Therapy/methods , Urination Disorders/etiology , Aged , Humans , Male , Middle Aged , Prostatic Neoplasms/blood , Prostatic Neoplasms/surgery , Quality of Life , Radiotherapy Dosage , Radiotherapy, Intensity-Modulated/adverse effects , Self Report , Severity of Illness Index , Urination/radiation effects
4.
Clin Lung Cancer ; 16(5): 358-65, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25843489

ABSTRACT

OBJECTIVE: The goal was to demonstrate that tailored therapy, according to tumor histology and epidermal growth factor receptor (EGFR) mutation status, and the introduction of novel drug combinations in the treatment of advanced non-small-cell lung cancer are promising for further investigation. METHODS: We conducted a multicenter phase II trial with mandatory EGFR testing and 2 strata. Patients with EGFR wild type received 4 cycles of bevacizumab, pemetrexed, and cisplatin, followed by maintenance with bevacizumab and pemetrexed until progression. Patients with EGFR mutations received bevacizumab and erlotinib until progression. Patients had computed tomography scans every 6 weeks and repeat biopsy at progression. The primary end point was progression-free survival (PFS) ≥ 35% at 6 months in stratum EGFR wild type; 77 patients were required to reach a power of 90% with an alpha of 5%. Secondary end points were median PFS, overall survival, best overall response rate (ORR), and tolerability. Further biomarkers and biopsy at progression were also evaluated. RESULTS: A total of 77 evaluable patients with EGFR wild type received an average of 9 cycles (range, 1-25). PFS at 6 months was 45.5%, median PFS was 6.9 months, overall survival was 12.1 months, and ORR was 62%. Kirsten rat sarcoma oncogene mutations and circulating vascular endothelial growth factor negatively correlated with survival, but thymidylate synthase expression did not. A total of 20 patients with EGFR mutations received an average of 16 cycles. PFS at 6 months was 70%, median PFS was 14 months, and ORR was 70%. Biopsy at progression was safe and successful in 71% of the cases. CONCLUSIONS: Both combination therapies were promising for further studies. Biopsy at progression was feasible and will be part of future SAKK studies to investigate molecular mechanisms of resistance.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , ErbB Receptors/genetics , Lung Neoplasms/drug therapy , Adult , Aged , Aged, 80 and over , Bevacizumab/administration & dosage , Biopsy , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Cisplatin/administration & dosage , Disease-Free Survival , Erlotinib Hydrochloride/administration & dosage , Feasibility Studies , Female , Humans , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Male , Middle Aged , Mutation , Pemetrexed/administration & dosage , Survival Rate
5.
EMBO J ; 32(8): 1115-27, 2013 Apr 17.
Article in English | MEDLINE | ID: mdl-23511973

ABSTRACT

Despite progress in mechanistic understanding of the RNA interference (RNAi) pathways, the subcellular sites of RNA silencing remain under debate. Here we show that loading of lipid-transfected siRNAs and endogenous microRNAs (miRNA) into RISC (RNA-induced silencing complexes), encounter of the target mRNA, and Ago2-mediated mRNA slicing in mammalian cells are nucleated at the rough endoplasmic reticulum (rER). Although the major RNAi pathway proteins are found in most subcellular compartments, the miRNA- and siRNA-loaded Ago2 populations co-sediment almost exclusively with the rER membranes, together with the RISC loading complex (RLC) factors Dicer, TAR RNA binding protein (TRBP) and protein activator of the interferon-induced protein kinase (PACT). Fractionation and membrane co-immune precipitations further confirm that siRNA-loaded Ago2 physically associates with the cytosolic side of the rER membrane. Additionally, RLC-associated double-stranded siRNA, diagnostic of RISC loading, and RISC-mediated mRNA cleavage products exclusively co-sediment with rER. Finally, we identify TRBP and PACT as key factors anchoring RISC to ER membranes in an RNA-independent manner. Together, our findings demonstrate that the outer rER membrane is a central nucleation site of siRNA-mediated RNA silencing.


Subject(s)
Endoplasmic Reticulum/metabolism , RNA Interference , RNA, Small Interfering/metabolism , Argonaute Proteins/analysis , DEAD-box RNA Helicases/analysis , Endoplasmic Reticulum/chemistry , HeLa Cells , Humans , Immunoprecipitation , RNA-Binding Proteins/analysis , Ribonuclease III/analysis
6.
RNA ; 15(7): 1265-73, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19474145

ABSTRACT

Nonsense-mediated mRNA decay (NMD) is a eukaryotic quality-control mechanism that recognizes and degrades mRNAs with premature termination codons (PTCs). In yeast, PTC-containing mRNAs are targeted to processing bodies (P-bodies), and yeast strains expressing an ATPase defective Upf1p mutant accumulate P-bodies. Here we show that in human cells, an ATPase-deficient UPF1 mutant and a fraction of UPF2 and UPF3b accumulate in cytoplasmic foci that co-localize with P-bodies. Depletion of the P-body component Ge-1, which prevents formation of microscopically detectable P-bodies, also impairs the localization of mutant UPF1, UPF2, and UPF3b in cytoplasmic foci. However, the accumulation of the ATPase-deficient UPF1 mutant in P-bodies is independent of UPF2, UPF3b, or SMG1, and the ATPase-deficient UPF1 mutant can localize into the P-bodies independent of its phosphorylation status. Most importantly, disruption of P-bodies by depletion of Ge-1 affects neither the mRNA levels of PTC-containing reporter genes nor endogenous NMD substrates. Consistent with the recently reported decapping-independent SMG6-mediated endonucleolytic decay of human nonsense mRNAs, our results imply that microscopically detectable P-bodies are not required for mammalian NMD.


Subject(s)
Codon, Nonsense/genetics , Cytoplasmic Structures/metabolism , RNA Stability , RNA, Messenger/metabolism , RNA-Binding Proteins/metabolism , Trans-Activators/metabolism , Transcription Factors/metabolism , HeLa Cells , Humans , Immunoblotting , Immunoenzyme Techniques , Mutation , Phosphatidylinositol 3-Kinases/genetics , Phosphatidylinositol 3-Kinases/metabolism , Phosphoinositide-3 Kinase Inhibitors , Phosphorylation , Protein Serine-Threonine Kinases , RNA Helicases , RNA, Messenger/genetics , RNA, Small Interfering/pharmacology , RNA-Binding Proteins/antagonists & inhibitors , RNA-Binding Proteins/genetics , Reverse Transcriptase Polymerase Chain Reaction , Trans-Activators/antagonists & inhibitors , Trans-Activators/genetics , Transcription Factors/antagonists & inhibitors , Transcription Factors/genetics
7.
Biochim Biophys Acta ; 1779(9): 538-49, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18657639

ABSTRACT

Among the different cellular surveillance mechanisms in charge to prevent production of faulty gene products, nonsense-mediated mRNA decay (NMD) represents a translation-dependent posttranscriptional process that selectively recognizes and degrades mRNAs whose open reading frame (ORF) is truncated by a premature translation termination codon (PTC, also called "nonsense codon"). In doing so, NMD protects the cell from accumulating C-terminally truncated proteins with potentially deleterious functions. Transcriptome profiling of NMD-deficient yeast, Drosophila, and human cells revealed that 3-10% of all mRNA levels are regulated (directly or indirectly) by NMD, indicating an important role of NMD in gene regulation that extends beyond quality control [J. Rehwinkel, J. Raes, E. Izaurralde, Nonsense-mediated mRNA decay: Target genes and functional diversification of effectors, Trends Biochem. Sci. 31 (2006) 639-646.[1]]. In this review, we focus on recent results from different model organisms that indicate an evolutionarily conserved mechanism for PTC identification.


Subject(s)
Codon, Nonsense/physiology , Gene Expression Regulation/physiology , RNA Processing, Post-Transcriptional , RNA Stability/physiology , Animals , Humans
8.
Trends Cell Biol ; 18(7): 315-21, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18524595

ABSTRACT

To ensure the accuracy of gene expression, eukaryotes have evolved several surveillance mechanisms. One of the best-studied quality control mechanisms is nonsense-mediated mRNA decay (NMD), which recognizes and degrades transcripts harboring a premature translation-termination codon (PTC), thereby preventing the production of faulty proteins. NMD regulates approximately 10% of human mRNAs, and its physiological importance is manifested by the fact that approximately 30% of disease-associated mutations generate PTCs. Although different mechanisms of PTC recognition have been proposed for different species, recent studies in Saccharomyces cerevisiae, Drosophila melanogaster, Caenorhabditis elegans, plants and mammals suggest a conserved model. Here, we summarize the latest results and discuss an emerging model for NMD and its implications for the regulation of gene expression.


Subject(s)
Gene Expression Regulation , RNA Stability , Saccharomyces cerevisiae/metabolism , Animals , Caenorhabditis elegans , Drosophila melanogaster , Evolution, Molecular , Genetic Diseases, Inborn/genetics , Humans , Models, Biological , Mutation , Protein Biosynthesis , Protein Structure, Tertiary , RNA Processing, Post-Transcriptional , RNA, Messenger/metabolism
9.
PLoS Biol ; 6(4): e92, 2008 Apr 29.
Article in English | MEDLINE | ID: mdl-18447580

ABSTRACT

Translation termination at premature termination codons (PTCs) triggers degradation of the aberrant mRNA, but the mechanism by which a termination event is defined as premature is still unclear. Here we show that the physical distance between the termination codon and the poly(A)-binding protein PABPC1 is a crucial determinant for PTC recognition in human cells. "Normal" termination codons can trigger nonsense-mediated mRNA decay (NMD) when this distance is extended; and vice versa, NMD can be suppressed by folding the poly(A) tail into proximity of a PTC or by tethering of PABPC1 nearby a PTC, indicating an evolutionarily conserved function of PABPC1 in promoting correct translation termination and antagonizing activation of NMD. Most importantly, our results demonstrate that spatial rearrangements of the 3' untranslated region can modulate the NMD pathway and thereby provide a novel mechanism for posttranscriptional gene regulation.


Subject(s)
3' Untranslated Regions/metabolism , RNA Processing, Post-Transcriptional , Codon, Nonsense/metabolism , Humans , Poly A/metabolism , Poly(A)-Binding Protein I/metabolism , RNA Stability , RNA, Messenger/metabolism
10.
J Biol Chem ; 282(22): 16079-85, 2007 Jun 01.
Article in English | MEDLINE | ID: mdl-17428806

ABSTRACT

Eukaryotes have evolved quality control mechanisms that prevent the expression of genes in which the protein coding potential is crippled by the presence of a premature translation-termination codon (PTC). In addition to nonsense-mediated mRNA decay (NMD), a well documented posttranscriptional consequence of the presence of a PTC in an mRNA, we recently reported the transcriptional silencing of PTC-containing immunoglobulin (Ig) mu and gamma minigenes when they are stably integrated into the genome of HeLa cells. Here we demonstrate that this transcriptional silencing of PTC-containing Ig-mu constructs requires active translation of the cognate mRNA, as it is not observed under conditions where translation of the PTC-containing mRNA is inhibited through an iron-responsive element in the 5'-untranslated region. Furthermore, RNA interference-mediated depletion of the essential NMD factor Upf1 not only abolishes NMD but also reduces the extent of nonsense-mediated transcriptional gene silencing (NMTGS). Collectively, our data indicate that NMTGS and NMD are linked, relying on the same mechanism for PTC recognition, and that the NMTGS pathway branches from the NMD pathway at a step after Upf1 function.


Subject(s)
Codon, Nonsense/metabolism , Gene Silencing/physiology , Immunoglobulin mu-Chains/biosynthesis , Protein Biosynthesis , RNA, Messenger/metabolism , Transcription, Genetic/physiology , Codon, Nonsense/genetics , HeLa Cells , Humans , Immunoglobulin gamma-Chains/biosynthesis , Immunoglobulin gamma-Chains/genetics , Immunoglobulin mu-Chains/genetics , Mutagenesis, Insertional , Protein Biosynthesis/genetics , RNA Helicases , RNA Stability/physiology , RNA, Messenger/genetics , Response Elements/genetics , Trans-Activators/genetics , Trans-Activators/metabolism
11.
Mol Cell ; 18(3): 307-17, 2005 Apr 29.
Article in English | MEDLINE | ID: mdl-15866173

ABSTRACT

Cells possess mechanisms to prevent synthesis of potentially deleterious truncated proteins caused by premature translation-termination codons (PTCs). Here, we show that PTCs can induce silencing of transcription of its cognate gene. We demonstrate for immunoglobulin (Ig)-mu minigenes expressed in HeLa cells that this transcriptional silencing is PTC specific and reversible by treatment of the cells with histone deacetylase inhibitors. Furthermore, PTC-containing Ig-mu minigenes are significantly more associated with K9-methylated histone H3 and less associated with acetylated H3 than the PTC-free Ig-mu minigene. This nonsense-mediated transcriptional gene silencing (NMTGS) is also observed with an Ig-gamma minigene, but not with several classic NMD reporter genes, suggesting that NMTGS might be specific for Ig genes. NMTGS represents a nonsense surveillance mechanism by which truncation of a gene's open reading frame (ORF) induces transcriptional silencing through chromatin remodeling. Remarkably, NMTGS is inhibited by overexpression of the putative siRNase 3'hExo, suggesting that siRNA-like molecules are involved in NMTGS.


Subject(s)
Codon, Nonsense , Gene Silencing , Genes, Immunoglobulin , Immunoglobulins/genetics , Transcription, Genetic , Base Sequence , Exonucleases/metabolism , Genes, Reporter , HeLa Cells , Histone Deacetylase Inhibitors , Histone Deacetylases/metabolism , Histones/metabolism , Humans , Lysine/metabolism , Methylation , RNA Interference , Sequence Alignment
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