Publications by authors named "Mairi Challinor"

7 Publications

  • Page 1 of 1

2-Aminomethylene-5-sulfonylthiazole Inhibitors of Lysyl Oxidase (LOX) and LOXL2 Show Significant Efficacy in Delaying Tumor Growth.

J Med Chem 2020 03 4;63(5):2308-2324. Epub 2019 Sep 4.

Drug Discovery Unit, Cancer Research UK Manchester Institute, University of Manchester, Alderley Park, Macclesfield SK10 4TG, United Kingdom.

The lysyl oxidase (LOX) family of extracellular proteins plays a vital role in catalyzing the formation of cross-links in fibrillar elastin and collagens leading to extracellular matrix (ECM) stabilization. These enzymes have also been implicated in tumor progression and metastatic disease and have thus become an attractive therapeutic target for many types of invasive cancers. Following our recently published work on the discovery of aminomethylenethiophenes (AMTs) as potent, orally bioavailable LOX/LOXL2 inhibitors, we report herein the discovery of a series of dual LOX/LOXL2 inhibitors, as well as a subseries of LOXL2-selective inhibitors, bearing an aminomethylenethiazole (AMTz) scaffold. Incorporation of a thiazole core leads to improved potency toward LOXL2 inhibition via an irreversible binding mode of inhibition. SAR studies have enabled the discovery of a predictive 3DQSAR model. Lead AMTz inhibitors exhibit improved pharmacokinetic properties and excellent antitumor efficacy, with significantly reduced tumor growth in a spontaneous breast cancer genetically engineered mouse model.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jmedchem.9b01112DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7073924PMC
March 2020

Anti-metastatic Inhibitors of Lysyl Oxidase (LOX): Design and Structure-Activity Relationships.

J Med Chem 2019 06 23;62(12):5863-5884. Epub 2019 May 23.

Cancer Research UK Centre for Cancer Therapeutics , The Institute of Cancer Research , 15 Cotswold Road , London SM2 5NG , United Kingdom.

Lysyl oxidase (LOX) is a secreted copper-dependent amine oxidase that cross-links collagens and elastin in the extracellular matrix and is a critical mediator of tumor growth and metastatic spread. LOX is a target for cancer therapy, and thus the search for therapeutic agents against LOX has been widely sought. We report herein the medicinal chemistry discovery of a series of LOX inhibitors bearing an aminomethylenethiophene (AMT) scaffold. High-throughput screening provided the initial hits. Structure-activity relationship (SAR) studies led to the discovery of AMT inhibitors with sub-micromolar half-maximal inhibitory concentrations (IC) in a LOX enzyme activity assay. Further SAR optimization yielded the orally bioavailable LOX inhibitor CCT365623 with good anti-LOX potency, selectivity, pharmacokinetic properties, as well as anti-metastatic efficacy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jmedchem.9b00335DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6937593PMC
June 2019

Regulation of RUNX1 dosage is crucial for efficient blood formation from hemogenic endothelium.

Development 2018 03 12;145(5). Epub 2018 Mar 12.

Stem Cell Biology Group, Cancer Research UK Manchester Institute, The University of Manchester, Wilmslow Road, Manchester M20 4BX, UK

During ontogeny, hematopoietic stem and progenitor cells arise from hemogenic endothelium through an endothelial-to-hematopoietic transition that is strictly dependent on the transcription factor RUNX1. Although it is well established that RUNX1 is essential for the onset of hematopoiesis, little is known about the role of RUNX1 dosage specifically in hemogenic endothelium and during the endothelial-to-hematopoietic transition. Here, we used the mouse embryonic stem cell differentiation system to determine if and how RUNX1 dosage affects hemogenic endothelium differentiation. The use of inducible expression combined with alterations in the expression of the RUNX1 co-factor CBFβ allowed us to evaluate a wide range of RUNX1 levels. We demonstrate that low RUNX1 levels are sufficient and necessary to initiate an effective endothelial-to-hematopoietic transition. Subsequently, RUNX1 is also required to complete the endothelial-to-hematopoietic transition and to generate functional hematopoietic precursors. In contrast, elevated levels of RUNX1 are able to drive an accelerated endothelial-to-hematopoietic transition, but the resulting cells are unable to generate mature hematopoietic cells. Together, our results suggest that RUNX1 dosage plays a pivotal role in hemogenic endothelium maturation and the establishment of the hematopoietic system.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1242/dev.149419DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5868988PMC
March 2018

EINCR1 is an EGF inducible lincRNA overexpressed in lung adenocarcinomas.

PLoS One 2017 21;12(7):e0181902. Epub 2017 Jul 21.

School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom.

Long non-coding RNAs are being increasingly recognised as important molecules involved in regulating a diverse array of biological functions. For example, many long non-coding RNAs have been associated with tumourigenesis and in this context their molecular functions often involves impacting on chromatin and transcriptional control processes. One important cellular control system that is often deregulated in cancer cells is the ERK MAP kinase pathway. Here we have investigated whether ERK pathway signaling in response to EGF stimulation, leads to changes in the production of long non-coding RNAs. We identify several different classes of EGF pathway-regulated lncRNAs. We focus on one of the inducible lincRNAs, EGF inducible long intergenic non-coding RNA 1 (EINCR1). EINCR1 is predominantly nuclear and shows delayed activation kinetics compared to other immediate-early EGF-inducible genes. In humans it is expressed in a tissue-specific manner and is mainly confined to the heart but it exhibits little evolutionary conservation. Importantly, in several cancers EINCR1 shows elevated expression levels which correlate with poor survival in lung adenocarcinoma patients. In the context of lung adenocarcinomas, EINCR1 expression is anti-correlated with the expression of several protein coding EGF-regulated genes. A potential functional connection is demonstrated as EINCR1 overexpression is shown to reduce the expression of EGF-regulated protein coding genes including FOS and FOSB.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0181902PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5521836PMC
September 2017

Dynamic Gene Regulatory Networks Drive Hematopoietic Specification and Differentiation.

Dev Cell 2016 Mar 25;36(5):572-87. Epub 2016 Feb 25.

Institute of Cancer end Genomic Sciences, College of Medicine and Dentistry, University of Birmingham, Birmingham B152TT, UK. Electronic address:

Metazoan development involves the successive activation and silencing of specific gene expression programs and is driven by tissue-specific transcription factors programming the chromatin landscape. To understand how this process executes an entire developmental pathway, we generated global gene expression, chromatin accessibility, histone modification, and transcription factor binding data from purified embryonic stem cell-derived cells representing six sequential stages of hematopoietic specification and differentiation. Our data reveal the nature of regulatory elements driving differential gene expression and inform how transcription factor binding impacts on promoter activity. We present a dynamic core regulatory network model for hematopoietic specification and demonstrate its utility for the design of reprogramming experiments. Functional studies motivated by our genome-wide data uncovered a stage-specific role for TEAD/YAP factors in mammalian hematopoietic specification. Our study presents a powerful resource for studying hematopoiesis and demonstrates how such data advance our understanding of mammalian development.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.devcel.2016.01.024DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4780867PMC
March 2016

Structure-Guided Design of Highly Selective and Potent Covalent Inhibitors of ERK1/2.

J Med Chem 2015 Jun 28;58(11):4790-801. Epub 2015 May 28.

The RAS/RAF/MEK/ERK signaling pathway has been targeted with a number of small molecule inhibitors in oncology clinical development across multiple disease indications. Importantly, cell lines with acquired resistance to B-RAF and MEK inhibitors have been shown to maintain sensitivity to ERK1/2 inhibition by small molecule inhibitors. There are a number of selective, noncovalent ERK1/2 inhibitors reported along with the promiscuous hypothemycin (and related analogues) that act via a covalent mechanism of action. This article reports the identification of multiple series of highly selective covalent ERK1/2 inhibitors informed by structure-based drug design (SBDD). As a starting point for these covalent inhibitors, reported ERK1/2 inhibitors and a chemical series identified via high-throughput screening were exploited. These approaches resulted in the identification of selective covalent tool compounds for potential in vitro and in vivo studies to assess the risks and or benefits of targeting this pathway through such a mechanism of action.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jmedchem.5b00466DOI Listing
June 2015

A Screening Assay Cascade to Identify and Characterize Novel Selective Estrogen Receptor Downregulators (SERDs).

J Biomol Screen 2015 Jul 7;20(6):748-59. Epub 2015 Apr 7.

Discovery Sciences, AstraZeneca, Macclesfield, Cheshire, UK

Here, we describe an approach to identify novel selective estrogen receptor downregulator (SERD) compounds with improved properties such as oral bioavailability and the potential of increased efficacy compared to currently marketed drug treatments. Previously, methodologies such as Western blotting and transient cell reporter assays have been used to identify and characterize SERD compounds, but such approaches can be limited due to low throughput and sensitivity, respectively. We have used an endogenous cell-imaging strategy that has both the throughput and sensitivity to support a large-scale hit-to-lead program to identify novel compounds. A screening cascade with a suite of assays has been developed to characterize compounds that modulate estrogen receptor α (ERα)-mediated signaling or downregulate ERα levels in cells. Initially, from a focused high-throughput screening, novel ERα binders were identified that could be modified chemically into ERα downregulators. Following this, cellular assays helped determine the mechanism of action of compounds to distinguish between on-target and off-target compounds and differentiate SERDs, selective estrogen receptor modulator (SERM) compounds, and agonist ERα ligands. Data are shown to exemplify the characterization of ERα-mediated signaling inhibitors using a selection of literature compounds and illustrate how this cascade has been used to drive the chemical design of novel SERD compounds.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/1087057115580298DOI Listing
July 2015