One of the major causes of failure in cancer chemotherapy is multidrug resistance (MDR), where cancer cells simultaneously become resistant to different anticancer drugs. Over-expression of membrane ...efflux pumps like P-glycoprotein (P-gp) that recognizes different chemotherapeutic agents and transports them out of the cell, plays a major role in MDR. The shortcoming of P-gp inhibitors in clinic has been attributed to their non-specific action on P-gp and/or non-selective distribution to non-target organs that leads to intolerable side effects by the P-gp inhibitor at doses required for P-gp inhibition upon systemic administration. Another major issue is the reduced elimination of P-gp substrates (e.g. anticancer drugs) and intolerable toxicities by anticancer drugs when co-administered with P-gp inhibitors. To overcome these shortcomings, new generation of P-gp inhibitors with improved specificity for P-gp have been developed. More recently, attention has been paid to the use of drug delivery systems primarily to restrict P-gp inhibition to tumor and reduce the non-selective inhibition of P-gp in non-target organs. This review will provide an overview and update on the status of P-gp inhibition approaches and the role of drug delivery systems in overcoming P-gp mediated MDR.
Clinical trials in children Joseph, Pathma D.; Craig, Jonathan C.; Caldwell, Patrina H.Y.
British journal of clinical pharmacology,
March 2015, Letnik:
79, Številka:
3
Journal Article
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Safety and efficacy data on many medicines used in children are surprisingly scarce. As a result children are sometimes given ineffective medicines or medicines with unknown harmful side effects. ...Better and more relevant clinical trials in children are needed to increase our knowledge of the effects of medicines and to prevent the delayed or non‐use of beneficial therapies. Clinical trials provide reliable evidence of treatment effects by rigorous controlled testing of interventions on human subjects. Paediatric trials are more challenging to conduct than trials in adults because of the paucity of funding, uniqueness of children and particular ethical concerns. Although current regulations and initiatives are improving the scope, quantity and quality of trials in children, there are still deficiencies that need to be addressed to accelerate radically equitable access to evidence‐based therapies in children.
Highlights • The Twelfth Eilat Conference on New Antiepileptic Drugs (AEDs)-EILAT XII. • Antiepileptic drugs in development. • Preclinical evaluation and clinical trials. • Development strategies of ...new AEDs.
Abstract
The Drug-Gene Interaction Database (DGIdb, www.dgidb.org) is a web resource that provides information on drug-gene interactions and druggable genes from publications, databases, and other ...web-based sources. Drug, gene, and interaction data are normalized and merged into conceptual groups. The information contained in this resource is available to users through a straightforward search interface, an application programming interface (API), and TSV data downloads. DGIdb 4.0 is the latest major version release of this database. A primary focus of this update was integration with crowdsourced efforts, leveraging the Drug Target Commons for community-contributed interaction data, Wikidata to facilitate term normalization, and export to NDEx for drug-gene interaction network representations. Seven new sources have been added since the last major version release, bringing the total number of sources included to 41. Of the previously aggregated sources, 15 have been updated. DGIdb 4.0 also includes improvements to the process of drug normalization and grouping of imported sources. Other notable updates include the introduction of a more sophisticated Query Score for interaction search results, an updated Interaction Score, the inclusion of interaction directionality, and several additional improvements to search features, data releases, licensing documentation and the application framework.
Macrocycles are ideal in efforts to tackle "difficult" targets, but our understanding of what makes them cell permeable and orally bioavailable is limited. Analysis of approximately 100 macrocyclic ...drugs and clinical candidates revealed that macrocycles are predominantly used for infectious disease and in oncology and that most belong to the macrolide or cyclic peptide class. A significant number (N = 34) of these macrocycles are administered orally, revealing that oral bioavailability can be obtained at molecular weights up to and above 1 kDa and polar surface areas ranging toward 250 Å(2). Moreover, insight from a group of "de novo designed" oral macrocycles in clinical studies and understanding of how cyclosporin A and model cyclic hexapeptides cross cell membranes may unlock wider opportunities in drug discovery. However, the number of oral macrocycles is still low and it remains to be seen if they are outliers or if macrocycles will open up novel oral druggable space.
The liver X receptors (LXRs) are pivotal regulators of lipid homeostasis in mammals. These transcription factors control the expression of a battery of genes involved in the uptake, transport, efflux ...and excretion of cholesterol in a tissue-dependent manner. The identification of the LXRs, and an increased understanding of the mechanisms by which LXR signalling regulates lipid homeostasis in different tissues (including the liver, intestine and brain), has highlighted new opportunities for therapeutic intervention in human metabolism. New strategies for the pharmacological manipulation of LXRs and their target genes offer promise for the treatment of human diseases in which lipids have a central role, including atherosclerosis and Alzheimer's disease.
Abstract
The Open Targets Platform (https://www.targetvalidation.org/) provides users with a queryable knowledgebase and user interface to aid systematic target identification and prioritisation for ...drug discovery based upon underlying evidence. It is publicly available and the underlying code is open source. Since our last update two years ago, we have had 10 releases to maintain and continuously improve evidence for target–disease relationships from 20 different data sources. In addition, we have integrated new evidence from key datasets, including prioritised targets identified from genome-wide CRISPR knockout screens in 300 cancer models (Project Score), and GWAS/UK BioBank statistical genetic analysis evidence from the Open Targets Genetics Portal. We have evolved our evidence scoring framework to improve target identification. To aid the prioritisation of targets and inform on the potential impact of modulating a given target, we have added evaluation of post-marketing adverse drug reactions and new curated information on target tractability and safety. We have also developed the user interface and backend technologies to improve performance and usability. In this article, we describe the latest enhancements to the Platform, to address the fundamental challenge that developing effective and safe drugs is difficult and expensive.
FGFR signaling is deregulated in many human cancers, and FGFR is considered a valid target in FGFR-deregulated tumors. Here, we examine the preclinical profile of futibatinib (TAS-120; ...1-(3S)-4-amino-3-(3,5-dimethoxyphenyl)ethynyl-1H-pyrazolo3, 4-d pyrimidin-1-yl-1-pyrrolidinyl-2-propen-1-one), a structurally novel, irreversible FGFR1-4 inhibitor. Among a panel of 296 human kinases, futibatinib selectively inhibited FGFR1-4 with IC
values of 1.4 to 3.7 nmol/L. Futibatinib covalently bound the FGFR kinase domain, inhibiting FGFR phosphorylation and, in turn, downstream signaling in FGFR-deregulated tumor cell lines. Futibatinib exhibited potent, selective growth inhibition of several tumor cell lines (gastric, lung, multiple myeloma, bladder, endometrial, and breast) harboring various
genomic aberrations. Oral administration of futibatinib led to significant dose-dependent tumor reduction in various FGFR-driven human tumor xenograft models, and tumor reduction was associated with sustained FGFR inhibition, which was proportional to the administered dose. The frequency of appearance of drug-resistant clones was lower with futibatinib than a reversible ATP-competitive FGFR inhibitor, and futibatinib inhibited several drug-resistant FGFR2 mutants, including the FGFR2 V565I/L gatekeeper mutants, with greater potency than any reversible FGFR inhibitors tested (IC
, 1.3-50.6 nmol/L). These results indicate that futibatinib is a novel orally available, potent, selective, and irreversible inhibitor of FGFR1-4 with a broad spectrum of antitumor activity in cell lines and xenograft models. These findings provide a strong rationale for testing futibatinib in patients with tumors oncogenically driven by FGFR genomic aberrations, with phase I to III trials ongoing. SIGNIFICANCE: Preclinical characterization of futibatinib, an irreversible FGFR1-4 inhibitor, demonstrates selective and potent antitumor activity against FGFR-deregulated cancer cell lines and xenograft models, supporting clinical evaluation in patients with FGFR-driven tumors. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/22/4986/F1.large.jpg.
NF-κB in the crosshairs: Rethinking an old riddle Bennett, Jason; Capece, Daria; Begalli, Federica ...
The international journal of biochemistry & cell biology,
February 2018, 2018-02-00, 20180201, Letnik:
95
Journal Article
Recenzirano
Odprti dostop
•NF-κB transcription factors are central coordinating regulators of immunity, inflammation and cell survival.•NF-κB pathway is aberrantly and stably activated in cancer.•The ubiquitous presence and ...pleiotropic physiological role of NF-κB dimers have thus far prevented the development of any clinically useful NF-κB inhibitor.•Emerging therapeutic approaches aim to achieve the cancer-selective inhibition of the NF-κB pathway as a way to overcome the preclusive toxicities of conventional IKKβ/NF-κB-targeting drugs.
Constitutive NF-κB signalling has been implicated in the pathogenesis of most human malignancies and virtually all non-malignant pathologies. Accordingly, the NF-κB pathway has been aggressively pursued as an attractive therapeutic target for drug discovery. However, the severe on-target toxicities associated with systemic NF-κB inhibition have thus far precluded the development of a clinically useful, NF-κB-targeting medicine as a way to treat patients with either oncological or non-oncological diseases. This minireview discusses some of the more promising approaches currently being developed to circumvent the preclusive safety liabilities of global NF-κB blockade by selectively targeting pathogenic NF-κB signalling in cancer, while preserving the multiple physiological functions of NF-κB in host defence responses and tissue homeostasis.
Since the discovery in the 1970s that plasma levels of high-density lipoprotein cholesterol (HDL-C) are inversely associated with cardiovascular outcome, it has been postulated that HDL is ...anti-atherogenic and that increasing HDL-C levels is a promising therapeutic strategy. However, the recent failure of three orally active, HDL-C-raising agents has introduced considerable controversy, prompting the question of whether increasing the cholesterol cargo of HDL in a non-selective manner is an effective pharmacological approach for the translation of its atheroprotective and vasculoprotective activities. The interrelationships between HDL-C concentration, HDL particle number and levels of diverse HDL particle subpopulations of defined composition are complex, as are their relationships with reverse cholesterol transport and other anti-atherogenic functions. Such complexity highlights the incompleteness of our understanding of the biology of HDL particles. This article examines the HDL hypothesis in molecular and mechanistic terms, focusing on features that have been addressed, those that remain to be tested, and potential new targets for future pharmacological interventions.
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