14 research outputs found

    Chemoproteomics Reveals Novel Protein and Lipid Kinase Targets of Clinical CDK4/6 Inhibitors in Lung Cancer

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    Several selective CDK4/6 inhibitors are in clinical trials for non-small cell lung cancer (NSCLC). Palbociclib (PD0332991) is included in the phase II/III Lung-MAP trial for squamous cell lung carcinoma (LUSQ). We noted differential cellular activity between palbociclib and the structurally related ribociclib (LEE011) in LUSQ cells. Applying an unbiased mass spectrometry-based chemoproteomics approach in H157 cells and primary tumor samples, we here report distinct proteome-wide target profiles of these two drug candidates in LUSQ, which encompass novel protein and, for palbociclib only, lipid kinases. In addition to CDK4 and 6, we observed CDK9 as a potent target of both drugs. Palbociclib interacted with several kinases not targeted by ribociclib, such as casein kinase 2 and PIK3R4, which regulate autophagy. Furthermore, palbociclib engaged several lipid kinases, most notably, PIK3CD and PIP4K2A/B/C. Accordingly, we observed modulation of autophagy and inhibition of AKT signaling by palbociclib but not ribociclib

    Comparison of Quantitative Mass Spectrometry Platforms for Monitoring Kinase ATP Probe Uptake in Lung Cancer

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    Recent developments in instrumentation and bioinformatics have led to new quantitative mass spectrometry platforms including LC–MS/MS with data-independent acquisition (DIA) and targeted analysis using parallel reaction monitoring mass spectrometry (LC–PRM), which provide alternatives to well-established methods, such as LC–MS/MS with data-dependent acquisition (DDA) and targeted analysis using multiple reaction monitoring mass spectrometry (LC–MRM). These tools have been used to identify signaling perturbations in lung cancers and other malignancies, supporting the development of effective kinase inhibitors and, more recently, providing insights into therapeutic resistance mechanisms and drug repurposing opportunities. However, detection of kinases in biological matrices can be challenging; therefore, activity-based protein profiling enrichment of ATP-utilizing proteins was selected as a test case for exploring the limits of detection of low-abundance analytes in complex biological samples. To examine the impact of different MS acquisition platforms, quantification of kinase ATP uptake following kinase inhibitor treatment was analyzed by four different methods: LC–MS/MS with DDA and DIA, LC–MRM, and LC–PRM. For discovery data sets, DIA increased the number of identified kinases by 21% and reduced missingness when compared with DDA. In this context, MRM and PRM were most effective at identifying global kinome responses to inhibitor treatment, highlighting the value of a priori target identification and manual evaluation of quantitative proteomics data sets. We compare results for a selected set of desthiobiotinylated peptides from PRM, MRM, and DIA and identify considerations for selecting a quantification method and postprocessing steps that should be used for each data acquisition strategy

    GSK3 Alpha and Beta Are New Functionally Relevant Targets of Tivantinib in Lung Cancer Cells

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    Tivantinib has been described as a potent and highly selective inhibitor of the receptor tyrosine kinase c-MET and is currently in advanced clinical development for several cancers including non-small cell lung cancer (NSCLC). However, recent studies suggest that tivantinib’s anticancer properties are unrelated to c-MET inhibition. Consistently, in determining tivantinib’s activity profile in a broad panel of NSCLC cell lines, we found that, in contrast to several more potent c-MET inhibitors, tivantinib reduces cell viability across most of these cell lines. Applying an unbiased, mass-spectrometry-based, chemical proteomics approach, we identified glycogen synthase kinase 3 (GSK3) alpha and beta as novel tivantinib targets. Subsequent validation showed that tivantinib displayed higher potency for GSK3α than for GSK3ÎČ and that pharmacological inhibition or simultaneous siRNA-mediated loss of GSK3α and GSK3ÎČ caused apoptosis. In summary, GSK3α and GSK3ÎČ are new kinase targets of tivantinib that play an important role in its cellular mechanism-of-action in NSCLC

    APOSTL: An Interactive Galaxy Pipeline for Reproducible Analysis of Affinity Proteomics Data

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    With continuously increasing scale and depth of coverage in affinity proteomics (AP–MS) data, the analysis and visualization is becoming more challenging. A number of tools have been developed to identify high-confidence interactions; however, a cohesive and intuitive pipeline for analysis and visualization is still needed. Here we present Automated Processing of SAINT Templated Layouts (APOSTL), a freely available Galaxy-integrated software suite and analysis pipeline for reproducible, interactive analysis of AP–MS data. APOSTL contains a number of tools woven together using Galaxy workflows, which are intuitive for the user to move from raw data to publication-quality figures within a single interface. APOSTL is an evolving software project with the potential to customize individual analyses with additional Galaxy tools and widgets using the R web application framework, Shiny. The source code, data, and documentation are freely available from GitHub (https://github.com/bornea/APOSTL) and other sources

    Dual Targeting of WEE1 and PLK1 by AZD1775 Elicits Single Agent Cellular Anticancer Activity

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    Inhibition of the WEE1 tyrosine kinase enhances anticancer chemotherapy efficacy. Accordingly, the WEE1 inhibitor AZD1775 (previously MK-1775) is currently under evaluation in clinical trials for cancer in combination with chemotherapy. AZD1775 has been reported to display high selectivity and is therefore used in many studies as a probe to interrogate WEE1 biology. However, AZD1775 also exhibits anticancer activity as a single agent although the underlying mechanism is not fully understood. Using a chemical proteomics approach, we here describe a proteome-wide survey of AZD1775 targets in lung cancer cells and identify several previously unknown targets in addition to WEE1. In particular, we observed polo-like kinase 1 (PLK1) as a new target of AZD1775. Importantly, <i>in vitro</i> kinase assays showed PLK1 and WEE1 to be inhibited by AZD1775 with similar potency. Subsequent loss-of-function experiments using RNAi for <i>WEE1</i> and <i>PLK1</i> suggested that targeting PLK1 enhances the pro-apoptotic and antiproliferative effects observed with <i>WEE1</i> knockdown. Combination of RNAi with AZD1775 treatment suggested WEE1 and PLK1 to be the most relevant targets for mediating AZD1775’s anticancer effects. Furthermore, disruption of <i>WEE1</i> by CRISPR-Cas9 sensitized H322 lung cancer cells to AZD1775 to a similar extent as the potent PLK1 inhibitor BI-2536 suggesting a complex crosstalk between PLK1 and WEE1. In summary, we show that AZD1775 is a potent dual WEE1 and PLK1 inhibitor, which limits its use as a specific molecular probe for WEE1. However, PLK1 inhibition makes important contributions to the single agent mechanism of action of AZD1775 and enhances its anticancer effects

    Kvalitet inom universitets och högskolebibliotek - redovisning av enkÀt 2008

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    Ett övergripande problem med utvĂ€rdering av informations/biblioteksverksamhet Ă€r att det fortfarande nĂ€stan enbart Ă€r traditionella uppgifter som utvĂ€rderas. En annan aspekt Ă€r att mĂ€ta kvalitet och nytta i andra Ă€n ekonomiska termer – d.v.s. kvalitativa indikatorer och mĂ„tt. Denna rapport innehĂ„ller en inventering (ej bedömning) vilka metoder, ansatser och initiativ som idag finns eller hĂ„ller pĂ„ att utvecklas pĂ„ lĂ€rosĂ€tena/biblioteken för att mĂ€ta kvalitet pĂ„ icke-kvantitativa sĂ€tt

    Hybrid drug-protein/protein-protein interaction networks of specific drug binding proteins.

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    <p>Individual cellular target profiles of nilotinib (green), dasatinib (red), bosutinib (yellow) and bafetinib (blue) were intersected with each other and overlaid with PPI data from public databases. Protein kinases and the oxidoreductase NQO2, as a validated target of nilotinib and to lesser extent of bafetinib, were considered to be direct drug binders (solid lines) and color-coded according to the drug they were interacting with. Shared kinase targets display a split color code. All other non-kinase proteins were assumed to be indirect binders (dashed lines) and displayed in grey. The analysis reveals distinct protein complexes, which are enriched by particular drugs and which are highlighted with the respectively colored background. <b>A</b>. Z-119 drug-protein interaction network. <b>B</b>. BV-173 drug-protein interaction network.</p

    Differential drug effects on cellular tyrosine phosphorylation.

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    <p>Cells were treated for 30 min with bafetinib (800 nM), bosutinib (400 nM), dasatinib (100 nM) and nilotinib (4 ”M), which are concentrations equivalent to reported maximum patient plasma concentrations, and DMSO control. Effects of individual drugs were determined by immunoblot analysis for BCR-ABL (α-ABL) and total phosphotyrosine (α-pY). Actin served as loading control. <b>A</b>. Dasatinib had the strongest impact on cellular tyrosine phosphorylation in BV-173 cells while the effects of bafetinib, nilotinib and particularly bosutinib were less pronounced. <b>B</b>. Dasatinib completely abolished cellular tyrosine phosphorylation in Z-119 cells. BCR-ABL levels were not appreciably affected, but it’s phosphorylation (marked by arrow) was inhibited by the drugs in either cell line.</p

    Graphical representation of binding specificity assessment.

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    <p>Using the example of dasatinib and BV-173 cells, the average spectral counts obtained from chemical proteomics were compared with the respective competition experiments in the presence of 20 ”M free drug in a double-logarithmic plot. Specific ( ♩) and non-specific (◊) binders were identified by definition of a specificity gate (grey area) with a ratio threshold of 2 and a minimum average spectral count of 10. For proteins that were not identified in the competition experiment, the minimum average spectral count was lowered to 1. </p

    A Miniaturized Chemical Proteomic Approach for Target Profiling of Clinical Kinase Inhibitors in Tumor Biopsies

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    While targeted therapy based on the idea of attenuating the activity of a preselected, therapeutically relevant protein has become one of the major trends in modern cancer therapy, no truly specific targeted drug has been developed and most clinical agents have displayed a degree of polypharmacology. Therefore, the specificity of anticancer therapeutics has emerged as a highly important but severely underestimated issue. Chemical proteomics is a powerful technique combining postgenomic drug-affinity chromatography with high-end mass spectrometry analysis and bioinformatic data processing to assemble a target profile of a desired therapeutic molecule. Due to high demands on the starting material, however, chemical proteomic studies have been mostly limited to cancer cell lines. Herein, we report a down-scaling of the technique to enable the analysis of very low abundance samples, as those obtained from needle biopsies. By a systematic investigation of several important parameters in pull-downs with the multikinase inhibitor bosutinib, the standard experimental protocol was optimized to 100 ÎŒg protein input. At this level, more than 30 well-known targets were detected per single pull-down replicate with high reproducibility. Moreover, as presented by the comprehensive target profile obtained from miniaturized pull-downs with another clinical drug, dasatinib, the optimized protocol seems to be extendable to other drugs of interest. Sixty distinct human and murine targets were finally identified for bosutinib and dasatinib in chemical proteomic experiments utilizing core needle biopsy samples from xenotransplants derived from patient tumor tissue. Altogether, the developed methodology proves robust and generic and holds many promises for the field of personalized health care
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