A high-resolution structure of a ligand-bound, soluble form of human monoglyceride lipase (MGL) is presented. The structure highlights a novel conformation of the regulatory lid-domain present in the lipase family as well as the binding mode of a pharmaceutically relevant reversible inhibitor. Analysis of the structure lacking the inhibitor indicates that the closed conformation can accommodate the native substrate 2-arachidonoyl glycerol. A model is proposed in which MGL undergoes conformational and electrostatic changes during the catalytic cycle ultimately resulting in its dissociation from the membrane upon completion of the cycle. In addition, the study outlines a successful approach to transform membrane associated proteins, which tend to aggregate upon purification, into a monomeric and soluble form.
Epstein-Barr virus (EBV) is a DNA tumor virus responsible for 1 to 2% of human cancers including subtypes of Burkitt’s lymphoma, Hodgkin’s lymphoma, gastric carcinoma, and nasopharyngeal carcinoma (NPC). Persistent latent infection drives EBV-associated tumorigenesis. Epstein-Barr nuclear antigen 1 (EBNA1) is the only viral protein consistently expressed in all EBV-associated tumors and is therefore an attractive target for therapeutic intervention. It is a multifunctional DNA binding protein critical for viral replication, genome maintenance, viral gene expression, and host cell survival. Using a fragment-based approach and x-ray crystallography, we identify a 2,3-disubstituted benzoic acid series that selectively inhibits the DNA binding activity of EBNA1. We characterize these inhibitors biochemically and in cell-based assays, including chromatin immunoprecipitation and DNA replication assays. In addition, we demonstrate the potency of EBNA1 inhibitors to suppress tumor growth in several EBV-dependent xenograft models, including patient-derived xenografts for NPC. These inhibitors selectively block EBV gene transcription and alter the cellular transforming growth factor–β (TGF-β) signaling pathway in NPC tumor xenografts. These EBNA1-specific inhibitors show favorable pharmacological properties and have the potential to be further developed for the treatment of EBV-associated malignancies.
Cannabidiol is the nonpsychoactive natural component of C. sativa that has been shown to be neuroprotective in multiple animal models. Our interest is to advance a therapeutic candidate for the orphan indication hepatic encephalopathy (HE). HE is a serious neurological disorder that occurs in patients with cirrhosis or liver failure. Although cannabidiol is effective in models of HE, it has limitations in terms of safety and oral bioavailability. Herein, we describe a series of side chain modified resorcinols that were designed for greater hydrophilicity and "drug likeness", while varying hydrogen bond donors, acceptors, architecture, basicity, neutrality, acidity, and polar surface area within the pendent group. Our primary screen evaluated the ability of the test agents to prevent damage to hippocampal neurons induced by ammonium acetate and ethanol at clinically relevant concentrations. Notably, KLS-13019 was 50-fold more potent and >400-fold safer than cannabidiol and exhibited an in vitro profile consistent with improved oral bioavailability.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.