Monoketone analogs of curcumin, a new class of Fanconi anemia pathway inhibitors

<p>Abstract</p> <p>Background</p> <p>The Fanconi anemia (FA) pathway is a multigene DNA damage response network implicated in the repair of DNA lesions that arise during replication or after exogenous DNA damage. The FA pathway displays synthetic lethal relationship with certain DNA repair genes such as <it>ATM </it>(Ataxia Telangectasia Mutated) that are frequently mutated in tumors. Thus, inhibition of FANCD2 monoubiquitylation (FANCD2-Ub), a key step in the FA pathway, might target tumor cells defective in ATM through synthetic lethal interaction. Curcumin was previously identified as a weak inhibitor of FANCD2-Ub. The aim of this study is to identify derivatives of curcumin with better activity and specificity.</p> <p>Results</p> <p>Using a replication-free assay in <it>Xenopus </it>extracts, we screened monoketone analogs of curcumin for inhibition of FANCD2-Ub and identified analog EF24 as a strong inhibitor. Mechanistic studies suggest that EF24 targets the FA pathway through inhibition of the NF-kB pathway kinase IKK. In HeLa cells, nanomolar concentrations of EF24 inhibited hydroxyurea (HU)-induced FANCD2-Ub and foci in a cell-cycle independent manner. Survival assays revealed that EF24 specifically sensitizes FA-competent cells to the DNA crosslinking agent mitomycin C (MMC). In addition, in contrast with curcumin, ATM-deficient cells are twofold more sensitive to EF24 than matched wild-type cells, consistent with a synthetic lethal effect between FA pathway inhibition and ATM deficiency. An independent screen identified 4H-TTD, a compound structurally related to EF24 that displays similar activity in egg extracts and in cells.</p> <p>Conclusions</p> <p>These results suggest that monoketone analogs of curcumin are potent inhibitors of the FA pathway and constitute a promising new class of targeted anticancer compounds.</p

Cost-effectiveness of laser Doppler imaging in burn care in the Netherlands

Background: Early accurate assessment of burn depth is important to determine the optimal treatment of burns. The method most used to determine burn depth is clinical assessment, which is the least expensive, but not the most accurate.Laser Doppler imaging (LDI) is a technique with which a more accurate (>95%) estimate of burn depth can be made by measuring the dermal perfusion. The actual effect on therapeutic decisions, cli

ERAP2 increases the abundance of a peptide submotif highly selective for the Birdshot Uveitis-associated HLA-A29

Birdshot Uveitis (BU) is a blinding inflammatory eye condition that only affects HLA-A29-positive individuals. Genetic association studies linked ERAP2 with BU, an aminopeptidase which trims peptides before their presentation by HLA class I at the cell surface, which suggests that ERAP2-dependent peptide presentation by HLA-A29 drives the pathogenesis of BU. However, it remains poorly understood whether the effects of ERAP2 on the HLA-A29 peptidome are distinct from its effect on other HLA allotypes. To address this, we focused on the effects of ERAP2 on the immunopeptidome in patient-derived antigen presenting cells. Using complementary HLA-A29-based and pan-class I immunopurifications, isotope-labeled naturally processed and presented HLA-bound peptides were sequenced by mass spectrometry. We show that the effects of ERAP2 on the N-terminus of ligands of HLA-A29 are shared across endogenous HLA allotypes, but discover and replicate that one peptide motif generated in the presence of ERAP2 is specifically bound by HLA-A29. This motif can be found in the amino acid sequence of putative autoantigens. We further show evidence for internal sequence specificity for ERAP2 imprinted in the immunopeptidome. These results reveal that ERAP2 can generate an HLA-A29-specific antigen repertoire, which supports that antigen presentation is a key disease pathway in BU.Proteomic

Infant High-Grade Gliomas Comprise Multiple Subgroups Characterized by Novel Targetable Gene Fusions and Favorable Outcomes.

Infant high-grade gliomas appear clinically distinct from their counterparts in older children, indicating that histopathologic grading may not accurately reflect the biology of these tumors. We have collected 241 cases under 4 years of age, and carried out histologic review, methylation profiling, and custom panel, genome, or exome sequencing. After excluding tumors representing other established entities or subgroups, we identified 130 cases to be part of an "intrinsic" spectrum of disease specific to the infant population. These included those with targetable MAPK alterations, and a large proportion of remaining cases harboring gene fusions targeting ALK (n = 31), NTRK1/2/3 (n = 21), ROS1 (n = 9), and MET (n = 4) as their driving alterations, with evidence of efficacy of targeted agents in the clinic. These data strongly support the concept that infant gliomas require a change in diagnostic practice and management. SIGNIFICANCE: Infant high-grade gliomas in the cerebral hemispheres comprise novel subgroups, with a prevalence of ALK, NTRK1/2/3, ROS1, or MET gene fusions. Kinase fusion-positive tumors have better outcome and respond to targeted therapy clinically. Other subgroups have poor outcome, with fusion-negative cases possibly representing an epigenetically driven pluripotent stem cell phenotype.See related commentary by Szulzewsky and Cimino, p. 904.This article is highlighted in the In This Issue feature, p. 890

Cost-Effectiveness of Laser Doppler Imaging in Burn Care in The Netherlands;: A Randomised Controlled Trial

Objectives: In patients with burns an early accurate diagnosis of burn depth is essential to determine optimal treatment. The combination of Laser Doppler imaging (LDI) and clinical assessment leads to an accurate estimate of burn depth. However, the actual effects of the introduction of LDI on therapeutic decisions, clinical outcomes and costs are unknown. The aim of our study was to analyse the effectiveness and cost-effectiveness of LDI in burn care. The effects of LDI on decision-making, clinical outcomes, costs, and cost-effectiveness were assessed. Methods: A randomised controlled trial was conducted in all three Dutch burn centres, including subsequent patients with burns of indeterminate depth. In the standard care (SC) group, burn depth and treatment choices were based on clinical assessment only, in the other group (LDI) clinical assessment and LDI results were combined. Primary outcome was the effect of the introduction of LDI on wound healing time. The economic evaluation was performed from a societal perspective with a bottom up approach, following the micro-costing method. Results: Mean time to wound healing from randomisation was 14.3 days in the LDI group and 15.5 days in the SC group (p= 0.258). In the subgroup of clinical patients requiring surgery earlier decision for surgery and a shorter wound healing time were observed in the LDI group (16.0 versus 19.9 days, p= 0.029). Mean total costs per patient were € 18 549 versus € 18 896 (p= 0.837). Conclusions: LDI proved to provide guidance for therapeutic decisions with a significantly shorter wound healing time in the subgroup of clinical patients requiring surgery. When time to surgery can be reduced by 2.4 days, similar to the time to decision for surgery in our study, cost savings of € 794 per scanned patient can be achieved

Retina-arrestin specific CD8+T cells are not implicated in HLA-A29-positive birdshot chorioretinitis

Background: HLA-A29-positive birdshot chorioretinitis (BCR) is an inflammatory eye disorder that is generally assumed to be caused by an autoimmune response to HLA-A29-presented peptides from retinal arrestin (SAG), yet the epitopes recognized by CD8+ T cells from patients remain to be identified. Objectives: The identification of natural ligands of SAG presented by HLA-A29. To quantify CD8+ T cells reactive to antigenic SAG peptides presented by HLA-A29 in patients and controls. Methods: We performed mass-spectrometry based immunopeptidomics of HLA-A29 of antigen-presenting cell lines from patients engineered to express SAG. MHC-I Dextramer technology was utilised to determine expansion of antigen-specific CD8+ T cells reactive to SAG peptides in complex with HLA-A29 in a cohort of BCR patients, HLA-A29-positive controls, and HLA-A29-negative controls. Results: We report on the naturally presented antigenic SAG peptides identified by sequencing the HLA-A29 immunopeptidome of antigen-presenting cells of patients. We show that the N-terminally extended SAG peptide precursors can be trimmed in vitro by the antigen-processing aminopeptidases ERAP1 and ERAP2. Unex-pectedly, no enhanced antigen engagement by CD8+ T cells upon stimulation with SAG peptides was observed in patients or HLA-A29-positive controls. Multiplexed HLA-A29-peptide dextramer profiling of a case-control cohort revealed that CD8+ T cells specific for these SAG peptides were neither detectable in peripheral blood nor in eye biopsies of patients. Conclusions: Collectively, these findings demonstrate that SAG is not a CD8+ T cell autoantigen and sharply contrast the paradigm in the pathogenesis of BCR. Therefore, the mechanism by which HLA-A29 is associated with BCR does not involve SAG.</p

Cost-Effectiveness of Laser Doppler Imaging in Burn Care in The Netherlands; A Randomised Controlled Trial

Objectives: In patients with burns an early accurate diagnosis of burn depth is essential to determine optimal treatment. The combination of Laser Doppler imaging (LDI) and clinical assessment leads to an accurate estimate of burn depth. However, the actual effects of the introduction of LDI on therapeutic decisions, clinical outcomes and costs are unknown. The aim of our study was to analyse the effectiveness and cost-effectiveness of LDI in burn care. The effects of LDI on decision-making, clinical outcomes, costs, and cost-effectiveness were assessed. Methods: A randomised controlled trial was conducted in all three Dutch burn centres, including subsequent patients with burns of indeterminate depth. In the standard care (SC) group, burn depth and treatment choices were based on clinical assessment only, in the other group (LDI) clinical assessment and LDI results were combined. Primary outcome was the effect of the introduction of LDI on wound healing time. The economic evaluation was performed from a societal perspective with a bottom up approach, following the micro-costing method. Results: Mean time to wound healing from randomisation was 14.3 days in the LDI group and 15.5 days in the SC group (p= 0.258). In the subgroup of clinical patients requiring surgery earlier decision for surgery and a shorter wound healing time were observed in the LDI group (16.0 versus 19.9 days, p= 0.029). Mean total costs per patient were € 18 549 versus € 18 896 (p= 0.837). Conclusions: LDI proved to provide guidance for therapeutic decisions with a significantly shorter wound healing time in the subgroup of clinical patients requiring surgery. When time to surgery can be reduced by 2.4 days, similar to the time to decision for surgery in our study, cost savings of € 794 per scanned patient can be achieved

ERAP2 Increases the Abundance of a Peptide Submotif Highly Selective for the Birdshot Uveitis-Associated HLA-A29

Contains fulltext : 231666.pdf (publisher's version ) (Open Access)Birdshot Uveitis (BU) is a blinding inflammatory eye condition that only affects HLA-A29-positive individuals. Genetic association studies linked ERAP2 with BU, an aminopeptidase which trims peptides before their presentation by HLA class I at the cell surface, which suggests that ERAP2-dependent peptide presentation by HLA-A29 drives the pathogenesis of BU. However, it remains poorly understood whether the effects of ERAP2 on the HLA-A29 peptidome are distinct from its effect on other HLA allotypes. To address this, we focused on the effects of ERAP2 on the immunopeptidome in patient-derived antigen presenting cells. Using complementary HLA-A29-based and pan-class I immunopurifications, isotope-labeled naturally processed and presented HLA-bound peptides were sequenced by mass spectrometry. We show that the effects of ERAP2 on the N-terminus of ligands of HLA-A29 are shared across endogenous HLA allotypes, but discover and replicate that one peptide motif generated in the presence of ERAP2 is specifically bound by HLA-A29. This motif can be found in the amino acid sequence of putative autoantigens. We further show evidence for internal sequence specificity for ERAP2 imprinted in the immunopeptidome. These results reveal that ERAP2 can generate an HLA-A29-specific antigen repertoire, which supports that antigen presentation is a key disease pathway in BU