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Bellany, F.

Publications and source records attributed to Bellany, F..

5 recordsLinked to original sources

SAMP-Score: A morphology-based machine learning classification method for screening pro-senescence compounds in p16 positive cancer cells

BackgroundSenescence identification is rendered challenging due to a lack of universally available biomarkers. This represents a bottleneck in efforts to develop pro-senescence therapeutics - agents designed to induce the arrest of cellular proliferation associated with a senescence response in cancer cells for therapeutic gain. This is particularly true in contexts such as basal-like breast cancer (BLBC), which often express high levels of widely reported senescence hallmarks, which has led to the designation of these subtypes as senescence marker positive (Sen-Mark+). Unfortunately, these are often cancers with the most limited treatment options, where novel pro-senescence compounds would be of potential clinical utility. ResultsTo address these challenges, we have developed SAMP-Score, a machine learning classification tool for identifying senescence induction in Sen-Mark+ cancers. This technique builds upon our previous observation that senescent cells develop distinct senescence-associated morphological profiles (SAMPs), which can be assessed readily in traditionally challenging contexts for senescence identification, including high-throughput screens. ConclusionsThrough application of SAMP-Score, we have identified QM5928, a novel pro-senescence compound, that is able to induce senescence in a variety of Sen-Mark+ cancers and has potential utility as a tool molecule to explore the mechanisms and pathways through which senescence induction occurs in these cells.

cancer biology↗

Characterisation of RNA guanine-7 methyltransferase (RNMT) using a small molecule approach

The maturation of the RNA cap involving guanosine N-7 methylation, catalyzed by the HsRNMT (RNA guanine-7 methyltransferase)-RAM (RNA guanine-N7 methyltransferase activating subunit) complex, is currently under investigation as a novel strategy to combat PIK3CA mutant breast cancer. However, the development of effective drugs is hindered by a limited understanding of the enzymes mechanism and a lack of small molecule inhibitors. Following the elucidation of the HsRNMT-RAM molecular mechanism, we report the biophysical characterization of two small molecule hits. Biophysics, biochemistry and structural biology confirm that both compounds bind competitively with cap and bind effectively to HsRNMT-RAM in the presence of the co-product SAM, with a binding affinity (KD) of approximately 1 M. This stabilisation of the enzyme-product complex results in uncompetitive inhibition. Finally, we describe the properties of the cap pocket and provided suggestions for further development of the tool compounds.

biochemistry↗

Application of an NMR/crystallography fragment screening platform for the assessment and rapid discovery of new HIV-CA binding fragments

Identification and assessment of novel targets is essential to combat drug resistance in the treatment of HIV/AIDS. HIV Capsid (HIV-CA), the protein playing a major role in both the early and late stages of the viral life cycle, has emerged as an important target. We have applied an NMR fragment screening platform and identified molecules that bind to the N-terminal domain (NTD) of HIV-CA at a site close to the interface with the C-terminal domain (CTD). Using X-ray crystallography, we have been able to obtain crystal structures to identify the binding mode of these compounds. This allowed for rapid progression of the initial, weak binding, fragment starting points to compounds 37 and 38, which have 19F-pK values of 5.3 and 5.4 respectively. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=56 SRC="FIGDIR/small/569544v2_ufig1.gif" ALT="Figure 1"> View larger version (6K): org.highwire.dtl.DTLVardef@1c7043corg.highwire.dtl.DTLVardef@e73044org.highwire.dtl.DTLVardef@11c1d9org.highwire.dtl.DTLVardef@1cd99e7_HPS_FORMAT_FIGEXP M_FIG C_FIG

pharmacology and toxicology↗

The Quest to Identify USP8 Inhibitors for Parkinsons Disease, a PAINful Experience.

Pan Assay INterference compoundS (PAINS) are known to be a source of false positives in High Throughput Screening (HTS) campaigns. This has become a major problem in medicinal chemistry, often resulting in undesirable project outcomes and increased overall cost. Our recent campaign to identify inhibitors of USP8 that could be used in the treatment of Parkinsons disease identified several PAINS that worked via a variety of mechanisms. Herein, we discuss the process developed to identify not only the PAINS but also confirming the interference mechanism causing their activity. We found in this project that our USP8 assay was susceptible to multiple modes of interference, making it difficult to identify genuine hit molecules. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=132 SRC="FIGDIR/small/556294v1_ufig1.gif" ALT="Figure 1"> View larger version (17K): org.highwire.dtl.DTLVardef@b917a6org.highwire.dtl.DTLVardef@1bfac47org.highwire.dtl.DTLVardef@c78e1dorg.highwire.dtl.DTLVardef@1434fdd_HPS_FORMAT_FIGEXP M_FIG C_FIG

pharmacology and toxicology↗

Covalent Aurora A regulation by the metabolic integrator coenzyme A

Aurora A is a cell cycle protein kinase implicated in multiple human cancers, and several Aurora A-specific kinase inhibitors have progressed into clinical trials. In this study, we report structural and cellular analysis of a novel biochemical mode of Aurora A inhibition, which occurs through reversible covalent interaction with the universal metabolic integrator coenzyme A (CoA). Mechanistically, the CoA 3-phospho ADP moiety interacts with Thr 217, an Aurora A selectivity filter, which permits the formation of an unprecedented covalent bond with Cys 290 in the kinase activation segment, lying some 15 [A] away. CoA modification (CoAlation) of endogenous Aurora A is rapidly induced by oxidative stresses at Cys 290 in human cells, and microinjection of CoA into mouse embryos perturbs meitoic spindle formation and chromosome alignment. Aurora A regulation by CoA reveals how targeting of Aurora A might be accomplished in the future by development of a double-anchored covalent inhibitor.

biochemistry↗