Transcription factor NRF2 as a therapeutic target for chronic diseases: a systems medicine approach

Systems medicine has a mechanism-based rather than a symptom- or organ-based approach to disease and identifies therapeutic targets in a nonhypothesis-driven manner. In this work, we apply this to transcription factor nuclear factor (erythroid-derived 2)-like 2 (NRF2) by cross-validating its position in a protein-protein interaction network (the NRF2 interactome) functionally linked to cytoprotection in low-grade stress, chronic inflammation, metabolic alterations, and reactive oxygen species formation. Multiscale network analysis of these molecular profiles suggests alterations of NRF2 expression and activity as a common mechanism in a subnetwork of diseases (the NRF2 diseasome). This network joins apparently heterogeneous phenotypes such as autoimmune, respiratory, digestive, cardiovascular, metabolic, and neurodegenerative diseases, along with cancer. Importantly, this approach matches and confirms in silico several applications for NRF2-modulating drugs validated in vivo at different phases of clinical development. Pharmacologically, their profile is as diverse as electrophilic dimethyl fumarate, synthetic triterpenoids like bardoxolone methyl and sulforaphane, protein-protein or DNA-protein interaction inhibitors, and even registered drugs such as metformin and statins, which activate NRF2 and may be repurposed for indications within the NRF2 cluster of disease phenotypes. Thus, NRF2 represents one of the first targets fully embraced by classic and systems medicine approaches to facilitate both drug development and drug repurposing by focusing on a set of disease phenotypes that appear to be mechanistically linked. The resulting NRF2 drugome may therefore rapidly advance several surprising clinical options for this subset of chronic diseases

Sustained Response of a Clivus Chordoma to Erlotinib after Imatinib Failure

Chordoma is a rare malignant axial tumour that develops from embryonic remnants of the notochord. Surgery and irradiation are the standard initial treatment. However, local recurrence is frequent and cytotoxic chemotherapy is inefficient. Transient activity of imatinib, a platelet-derived growth factor receptor inhibitor, was described in a phase II study. Activity of epidermal growth factor receptor (EGFR) inhibitors (erlotinib, gefitinib) has also been shown in a few recent case reports. We describe a 68-year-old female in whom clivus chordoma recurred after surgery and radiotherapy. The tumour progressed despite imatinib treatment. A partial and sustained response (28+ months) was obtained using erlotinib, an EGFR inhibitor. Erlotinib should be evaluated in a prospective trial investigating new potential therapies against recurrent chordoma

Insecticide Resistance in <i>Aedes aegypti</i> Mosquitoes: Possible Detection of <i>kdr</i> F1534C, S989P, and V1016G Triple Mutation in Benin, West Africa

Epidemics of arboviruses in general, and dengue fever in particular, are an increasing threat in areas where Aedes (Ae.) aegypti is present. The effectiveness of chemical control of Ae. aegypti is jeopardized by the increasing frequency of insecticide resistance. The aim of this study was to determine the susceptibility status of Ae. aegypti to public health insecticides and assess the underlying mechanisms driving insecticide resistance. Ae. aegypti eggs were collected in two study sites in the vicinity of houses for two weeks using gravid Aedes traps (GATs). After rearing the mosquitoes to adulthood, female Ae. aegypti were exposed to diagnostic doses of permethrin, deltamethrin and bendiocarb, using Centers for Disease Control and Prevention (CDC) bottle bioassays. Unexposed, un-engorged female Ae. aegypti were tested individually for mixed-function oxidase (MFO), glutathione-S-transferase (GST) and α and β esterase activities. Finally, allele-specific PCR (AS-PCR) was used to detect possible kdr mutations (F1534C, S989P, and V1016G) in the voltage-gated sodium channel gene in insecticide-exposed Ae. aegypti. Most traps were oviposition positive; 93.2% and 97% of traps contained Ae. aegypti eggs in the 10ème arrondissement of Cotonou and in Godomey-Togoudo, respectively. Insecticide bioassays detected resistance to permethrin and deltamethrin in both study sites and complete susceptibility to bendiocarb. By comparison to the insecticide-susceptible Rockefeller strain, field Ae. aegypti populations had significantly higher levels of GSTs and significantly lower levels of α and β esterases; there was no significant difference between levels of MFOs. AS-PCR genotyping revealed the possible presence of 3 kdr mutations (F1534C, S989P, and V1016G) at high frequencies; 80.9% (228/282) of the Ae. aegypti tested had at least 1 mutation, while the simultaneous presence of all 3 kdr mutations was identified in 13 resistant individuals. Study findings demonstrated phenotypic pyrethroid resistance, the over-expression of key detoxification enzymes, and the possible presence of several kdr mutations in Ae. aegypti populations, emphasizing the urgent need to implement vector control strategies targeting arbovirus vector species in Benin

Les actualités marquantes du congrès Targeted Anticancer Therapies — TAT 2016

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Resensitization to Nivolumab after Intratumoral Chemotherapy in Recurrent Head and Neck Squamous Cell Cancer: A Report of 2 Cases

International audienceThe survival of patients with head and neck squamous cancer with locoregional recurrence is short if salvage surgery or radiation cannot be performed. Systemic chemotherapy based on platinum salts and cetuximab produces only partial and transient responses. Immune checkpoint inhibitors (i.e., nivolumab) lead to a low complete response rate of only about 10%, but in some cases the effects can be long-lasting. Intratumoral chemotherapy (ITC) has been proposed for patients with local recurrence of head and neck squamous cell carcinoma with an objective response rate of 27-50%. However, it often leads to peritumoral tissue necrosis, and the duration of local control is limited. Here, we present 2 patients with head and neck squamous cell cancer whose local recurrences were refractory to intravenous chemotherapy and nivolumab. ITC using nonnecrotizing molecules, associated with nivolumab, led to complete stable local and distant response. ITC seems to trigger tumor resensitization to previously ineffective immunotherapy. This combination deserves an evaluation in the framework of a prospective trial

Alpha-fetoprotein is a biomarker of unfolded protein response and altered proteostasis in hepatocellular carcinoma cells exposed to sorafenib

International audienceSorafenib is the treatment of reference for advanced hepatocellular carcinoma (HCC). A decrease in the serum levels of Alpha-fetoprotein (AFP) is reported to be the biological parameter that is best associated with disease control by sorafenib. In order to provide a biological rationale for the variations of APP, we analyzed the various steps of AFP production in human HCC cell lines exposed to sorafenib. Sorafenib dramatically reduced the levels of APP produced by HCC cells independently of its effect on cell viability. The mRNA levels of APP decreased upon sorafenib treatment, while the AFP protein remained localized in the Golgi apparatus. Sorafenib activated the Regulated Inositol-Requiring Enzyme-1 alpha (IRE-1 alpha) and the PKR-like ER Kinase (PERK)-dependent arms of the Unfolded Protein Response (UPR). The inhibition of IRE-1 alpha partially restored the mRNA levels of AFP upon treatment with sorafenib. The inhibition of both pathways partially prevented the drop in the production of AFP induced by sorafenib. The findings provide new insights on the regulation of APP, and identify it as a biomarker suitable for the exploration of HCC cell proteostasis in the context of therapeutic targeting. (C) 2015 Elsevier Ireland Ltd. All rights reserved