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  1. Article ; Online: Maximum Entropy Framework for Predictive Inference of Cell Population Heterogeneity and Responses in Signaling Networks.

    Dixit, Purushottam D / Lyashenko, Eugenia / Niepel, Mario / Vitkup, Dennis

    Cell systems

    2019  Volume 10, Issue 2, Page(s) 204–212.e8

    Abstract: Predictive models of signaling networks are essential for understanding cell population heterogeneity and designing rational interventions in disease. However, using computational models to predict heterogeneity of signaling dynamics is often challenging ...

    Abstract Predictive models of signaling networks are essential for understanding cell population heterogeneity and designing rational interventions in disease. However, using computational models to predict heterogeneity of signaling dynamics is often challenging because of the extensive variability of biochemical parameters across cell populations. Here, we describe a maximum entropy-based framework for inference of heterogeneity in dynamics of signaling networks (MERIDIAN). MERIDIAN estimates the joint probability distribution over signaling network parameters that is consistent with experimentally measured cell-to-cell variability of biochemical species. We apply the developed approach to investigate the response heterogeneity in the EGFR/Akt signaling network. Our analysis demonstrates that a significant fraction of cells exhibits high phosphorylated Akt (pAkt) levels hours after EGF stimulation. Our findings also suggest that cells with high EGFR levels predominantly contribute to the subpopulation of cells with high pAkt activity. We also discuss how MERIDIAN can be extended to accommodate various experimental measurements.
    MeSH term(s) Cells/metabolism ; Entropy ; Genetic Heterogeneity ; Humans ; Signal Transduction
    Language English
    Publishing date 2019-12-18
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 2854138-8
    ISSN 2405-4720 ; 2405-4712
    ISSN (online) 2405-4720
    ISSN 2405-4712
    DOI 10.1016/j.cels.2019.11.010
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Receptor-based mechanism of relative sensing and cell memory in mammalian signaling networks.

    Lyashenko, Eugenia / Niepel, Mario / Dixit, Purushottam D / Lim, Sang Kyun / Sorger, Peter K / Vitkup, Dennis

    eLife

    2020  Volume 9

    Abstract: Detecting relative rather than absolute changes in extracellular signals enables cells to make decisions in constantly fluctuating environments. It is currently not well understood how mammalian signaling networks store the memories of past stimuli and ... ...

    Abstract Detecting relative rather than absolute changes in extracellular signals enables cells to make decisions in constantly fluctuating environments. It is currently not well understood how mammalian signaling networks store the memories of past stimuli and subsequently use them to compute relative signals, that is perform fold change detection. Using the growth factor-activated PI3K-Akt signaling pathway, we develop here computational and analytical models, and experimentally validate a novel non-transcriptional mechanism of relative sensing in mammalian cells. This mechanism relies on a new form of cellular memory, where cells effectively encode past stimulation levels in the abundance of cognate receptors on the cell surface. The surface receptor abundance is regulated by background signal-dependent receptor endocytosis and down-regulation. We show the robustness and specificity of relative sensing for two physiologically important ligands, epidermal growth factor (EGF) and hepatocyte growth factor (HGF), and across wide ranges of background stimuli. Our results suggest that similar mechanisms of cell memory and fold change detection may be important in diverse signaling cascades and multiple biological contexts.
    MeSH term(s) Cell Line ; Cell Membrane/metabolism ; Cell Physiological Phenomena/physiology ; Class I Phosphatidylinositol 3-Kinases/metabolism ; Endocytosis/physiology ; Epidermal Growth Factor/metabolism ; Extracellular Space/metabolism ; Hepatocyte Growth Factor/metabolism ; Humans ; Models, Biological ; Proto-Oncogene Proteins c-akt/metabolism ; Receptors, Cell Surface/metabolism ; Signal Transduction/physiology
    Chemical Substances HGF protein, human ; Receptors, Cell Surface ; Epidermal Growth Factor (62229-50-9) ; Hepatocyte Growth Factor (67256-21-7) ; Class I Phosphatidylinositol 3-Kinases (EC 2.7.1.137) ; Proto-Oncogene Proteins c-akt (EC 2.7.11.1)
    Language English
    Publishing date 2020-01-21
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 2687154-3
    ISSN 2050-084X ; 2050-084X
    ISSN (online) 2050-084X
    ISSN 2050-084X
    DOI 10.7554/eLife.50342
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Alternative drug sensitivity metrics improve preclinical cancer pharmacogenomics.

    Hafner, Marc / Niepel, Mario / Sorger, Peter K

    Nature biotechnology

    2017  Volume 35, Issue 6, Page(s) 500–502

    Language English
    Publishing date 2017-06-07
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1311932-1
    ISSN 1546-1696 ; 1087-0156
    ISSN (online) 1546-1696
    ISSN 1087-0156
    DOI 10.1038/nbt.3882
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Tensor clustering with algebraic constraints gives interpretable groups of crosstalk mechanisms in breast cancer.

    Seigal, Anna / Beguerisse-Díaz, Mariano / Schoeberl, Birgit / Niepel, Mario / Harrington, Heather A

    Journal of the Royal Society, Interface

    2019  Volume 16, Issue 151, Page(s) 20180661

    Abstract: We introduce a tensor-based clustering method to extract sparse, low-dimensional structure from high-dimensional, multi-indexed datasets. This framework is designed to enable detection of clusters of data in the presence of structural requirements which ... ...

    Abstract We introduce a tensor-based clustering method to extract sparse, low-dimensional structure from high-dimensional, multi-indexed datasets. This framework is designed to enable detection of clusters of data in the presence of structural requirements which we encode as algebraic constraints in a linear program. Our clustering method is general and can be tailored to a variety of applications in science and industry. We illustrate our method on a collection of experiments measuring the response of genetically diverse breast cancer cell lines to an array of ligands. Each experiment consists of a cell line-ligand combination, and contains time-course measurements of the early signalling kinases MAPK and AKT at two different ligand dose levels. By imposing appropriate structural constraints and respecting the multi-indexed structure of the data, the analysis of clusters can be optimized for biological interpretation and therapeutic understanding. We then perform a systematic, large-scale exploration of mechanistic models of MAPK-AKT crosstalk for each cluster. This analysis allows us to quantify the heterogeneity of breast cancer cell subtypes, and leads to hypotheses about the signalling mechanisms that mediate the response of the cell lines to ligands.
    MeSH term(s) Algorithms ; Breast Neoplasms/metabolism ; Breast Neoplasms/pathology ; Cluster Analysis ; Female ; Humans ; MAP Kinase Signaling System ; Mitogen-Activated Protein Kinase Kinases/metabolism ; Models, Biological ; Proto-Oncogene Proteins c-akt/metabolism
    Chemical Substances Proto-Oncogene Proteins c-akt (EC 2.7.11.1) ; Mitogen-Activated Protein Kinase Kinases (EC 2.7.12.2)
    Language English
    Publishing date 2019-04-08
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2156283-0
    ISSN 1742-5662 ; 1742-5689
    ISSN (online) 1742-5662
    ISSN 1742-5689
    DOI 10.1098/rsif.2018.0661
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Measuring Cancer Drug Sensitivity and Resistance in Cultured Cells.

    Niepel, Mario / Hafner, Marc / Chung, Mirra / Sorger, Peter K

    Current protocols in chemical biology

    2017  Volume 9, Issue 2, Page(s) 55–74

    Abstract: Measuring the potencies of small-molecule drugs in cell lines is a critical aspect of preclinical pharmacology. Such experiments are also prototypical of high-throughput experiments in multi-well plates. The procedure is simple in principle, but many ... ...

    Abstract Measuring the potencies of small-molecule drugs in cell lines is a critical aspect of preclinical pharmacology. Such experiments are also prototypical of high-throughput experiments in multi-well plates. The procedure is simple in principle, but many unrecognized factors can affect the results, potentially making data unreliable. The procedures for measuring drug response described here were developed by the NIH LINCS program to improve reproducibility. Key features include maximizing uniform cell growth during the assay period, accounting for the effects of cell density on response, and correcting sensitivity measures for differences in proliferation rates. Two related protocols are described: one involves an endpoint measure well-suited to large-scale studies and the second is a time-dependent measurement that reveals changes in response over time. The methods can be adapted to other types of plate-based experiments. © 2017 by John Wiley & Sons, Inc.
    MeSH term(s) Antineoplastic Agents/pharmacology ; Cell Proliferation/drug effects ; Cell Survival ; Dose-Response Relationship, Drug ; Drug Resistance, Neoplasm ; Drug Screening Assays, Antitumor/methods ; Endpoint Determination ; Humans ; MCF-7 Cells ; Time Factors
    Chemical Substances Antineoplastic Agents
    Language English
    Publishing date 2017-06-19
    Publishing country United States
    Document type Journal Article
    ISSN 2160-4762
    ISSN (online) 2160-4762
    DOI 10.1002/cpch.21
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Designing Drug-Response Experiments and Quantifying their Results.

    Hafner, Marc / Niepel, Mario / Subramanian, Kartik / Sorger, Peter K

    Current protocols in chemical biology

    2017  Volume 9, Issue 2, Page(s) 96–116

    Abstract: We developed a Python package to help in performing drug-response experiments at medium and high throughput and evaluating sensitivity metrics from the resulting data. In this article, we describe the steps involved in (1) generating files necessary for ... ...

    Abstract We developed a Python package to help in performing drug-response experiments at medium and high throughput and evaluating sensitivity metrics from the resulting data. In this article, we describe the steps involved in (1) generating files necessary for treating cells with the HP D300 drug dispenser, by pin transfer or by manual pipetting; (2) merging the data generated by high-throughput slide scanners, such as the Perkin Elmer Operetta, with treatment annotations; and (3) analyzing the results to obtain data normalized to untreated controls and sensitivity metrics such as IC
    MeSH term(s) Dose-Response Relationship, Drug ; Drug Evaluation, Preclinical/instrumentation ; Drug Evaluation, Preclinical/methods ; High-Throughput Screening Assays ; Inhibitory Concentration 50 ; Software
    Language English
    Publishing date 2017-06-19
    Publishing country United States
    Document type Journal Article
    ISSN 2160-4762
    ISSN (online) 2160-4762
    DOI 10.1002/cpch.19
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Selective Pharmaceutical Inhibition of PARP14 Mitigates Allergen-Induced IgE and Mucus Overproduction in a Mouse Model of Pulmonary Allergic Response.

    Eddie, Alex M / Chen, Kevin W / Schenkel, Laurie B / Swinger, Kerren K / Molina, Jennifer R / Kunii, Kaiko / Raybuck, Ariel L / Keilhack, Heike / Gibson-Corley, Katherine N / Niepel, Mario / Peebles, R Stokes / Boothby, Mark R / Cho, Sung Hoon

    ImmunoHorizons

    2022  Volume 6, Issue 7, Page(s) 432–446

    Abstract: The type 2 cytokines IL-4 and IL-13, which share use of an IL-4 receptor α-chain and its nuclear induction of the transcription factor STAT6, are crucial in elicitation and maintenance of allergic conditions including asthma. STAT6 binds poly(ADP-ribose) ...

    Abstract The type 2 cytokines IL-4 and IL-13, which share use of an IL-4 receptor α-chain and its nuclear induction of the transcription factor STAT6, are crucial in elicitation and maintenance of allergic conditions including asthma. STAT6 binds poly(ADP-ribose) polymerase (PARP)14, an ADP-ribosyl monotransferase. Elimination of PARP14 by gene targeting led to attenuation of OVA-specific allergic lung inflammation. However, PARP14 has multiple functional domains apart from the portion that catalyzes ADP-ribosylation, and it is not clear whether inhibition of the catalytic function has any biological consequence. Using BALB/c mice sensitized to the allergen
    MeSH term(s) Allergens ; Animals ; Asthma/drug therapy ; Disease Models, Animal ; Immunoglobulin E ; Mice ; Mucus/metabolism ; Pharmaceutical Preparations/metabolism ; Poly(ADP-ribose) Polymerase Inhibitors/metabolism ; Poly(ADP-ribose) Polymerase Inhibitors/pharmacology ; Poly(ADP-ribose) Polymerase Inhibitors/therapeutic use ; Poly(ADP-ribose) Polymerases/genetics ; Poly(ADP-ribose) Polymerases/metabolism ; Poly(ADP-ribose) Polymerases/therapeutic use
    Chemical Substances Allergens ; Pharmaceutical Preparations ; Poly(ADP-ribose) Polymerase Inhibitors ; Immunoglobulin E (37341-29-0) ; Parp14 protein, mouse (EC 2.4.2.30) ; Poly(ADP-ribose) Polymerases (EC 2.4.2.30)
    Language English
    Publishing date 2022-07-11
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 2573-7732
    ISSN (online) 2573-7732
    DOI 10.4049/immunohorizons.2100107
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Multiplexed and reproducible high content screening of live and fixed cells using Dye Drop.

    Mills, Caitlin E / Subramanian, Kartik / Hafner, Marc / Niepel, Mario / Gerosa, Luca / Chung, Mirra / Victor, Chiara / Gaudio, Benjamin / Yapp, Clarence / Nirmal, Ajit J / Clark, Nicholas / Sorger, Peter K

    Nature communications

    2022  Volume 13, Issue 1, Page(s) 6918

    Abstract: High-throughput measurement of cells perturbed using libraries of small molecules, gene knockouts, or different microenvironmental factors is a key step in functional genomics and pre-clinical drug discovery. However, it remains difficult to perform ... ...

    Abstract High-throughput measurement of cells perturbed using libraries of small molecules, gene knockouts, or different microenvironmental factors is a key step in functional genomics and pre-clinical drug discovery. However, it remains difficult to perform accurate single-cell assays in 384-well plates, limiting many studies to well-average measurements (e.g., CellTiter-Glo®). Here we describe a public domain Dye Drop method that uses sequential density displacement and microscopy to perform multi-step assays on living cells. We use Dye Drop cell viability and DNA replication assays followed by immunofluorescence imaging to collect single-cell dose-response data for 67 investigational and clinical-grade small molecules in 58 breast cancer cell lines. By separating the cytostatic and cytotoxic effects of drugs computationally, we uncover unexpected relationships between the two. Dye Drop is rapid, reproducible, customizable, and compatible with manual or automated laboratory equipment. Dye Drop improves the tradeoff between data content and cost, enabling the collection of information-rich perturbagen-response datasets.
    MeSH term(s) Drug Discovery/methods ; Cell Survival ; Staining and Labeling ; Antineoplastic Agents/pharmacology ; Microscopy ; High-Throughput Screening Assays/methods
    Chemical Substances Antineoplastic Agents
    Language English
    Publishing date 2022-11-14
    Publishing country England
    Document type Journal Article
    ZDB-ID 2553671-0
    ISSN 2041-1723 ; 2041-1723
    ISSN (online) 2041-1723
    ISSN 2041-1723
    DOI 10.1038/s41467-022-34536-7
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  9. Article ; Online: Growth rate inhibition metrics correct for confounders in measuring sensitivity to cancer drugs.

    Hafner, Marc / Niepel, Mario / Chung, Mirra / Sorger, Peter K

    Nature methods

    2016  Volume 13, Issue 6, Page(s) 521–527

    Abstract: Drug sensitivity and resistance are conventionally quantified by IC50 or Emax values, but these metrics are highly sensitive to the number of divisions taking place over the course of a response assay. The dependency of IC50 and Emax on division rate ... ...

    Abstract Drug sensitivity and resistance are conventionally quantified by IC50 or Emax values, but these metrics are highly sensitive to the number of divisions taking place over the course of a response assay. The dependency of IC50 and Emax on division rate creates artefactual correlations between genotype and drug sensitivity, while obscuring valuable biological insights and interfering with biomarker discovery. We derive alternative small molecule drug-response metrics that are insensitive to division number. These are based on estimation of the magnitude of drug-induced growth rate inhibition (GR) using endpoint or time-course assays. We show that GR50 and GRmax are superior to conventional metrics for assessing the effects of small molecule drugs in dividing cells. Moreover, adopting GR metrics requires only modest changes in experimental protocols. We expect GR metrics to improve the study of cell signaling and growth using small molecules and biologics and to facilitate the discovery of drug-response biomarkers and the identification of drugs effective against specific patient-derived tumor cells.
    MeSH term(s) Antineoplastic Agents/pharmacology ; Biological Products/pharmacology ; Cell Count ; Cell Culture Techniques ; Cell Line, Tumor ; Cell Proliferation/drug effects ; Computer Simulation ; Dose-Response Relationship, Drug ; Drug Discovery/methods ; Drug Resistance, Neoplasm ; High-Throughput Screening Assays ; Humans ; Inhibitory Concentration 50 ; Models, Theoretical ; Small Molecule Libraries/pharmacology
    Chemical Substances Antineoplastic Agents ; Biological Products ; Small Molecule Libraries
    Language English
    Publishing date 2016-05-02
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, N.I.H., Extramural
    ZDB-ID 2169522-2
    ISSN 1548-7105 ; 1548-7091
    ISSN (online) 1548-7105
    ISSN 1548-7091
    DOI 10.1038/nmeth.3853
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  10. Article ; Online: PARP14 inhibition restores PD-1 immune checkpoint inhibitor response following IFNγ-driven acquired resistance in preclinical cancer models.

    Wong, Chun Wai / Evangelou, Christos / Sefton, Kieran N / Leshem, Rotem / Zhang, Wei / Gopalan, Vishaka / Chattrakarn, Sorayut / Fernandez Carro, Macarena Lucia / Uzuner, Erez / Mole, Holly / Wilcock, Daniel J / Smith, Michael P / Sergiou, Kleita / Telfer, Brian A / Isaac, Dervla T / Liu, Chang / Perl, Nicholas R / Marie, Kerrie / Lorigan, Paul /
    Williams, Kaye J / Rao, Patricia E / Nagaraju, Raghavendar T / Niepel, Mario / Hurlstone, Adam F L

    Nature communications

    2023  Volume 14, Issue 1, Page(s) 5983

    Abstract: Resistance mechanisms to immune checkpoint blockade therapy (ICBT) limit its response duration and magnitude. Paradoxically, Interferon γ (IFNγ), a key cytokine for cellular immunity, can promote ICBT resistance. Using syngeneic mouse tumour models, we ... ...

    Abstract Resistance mechanisms to immune checkpoint blockade therapy (ICBT) limit its response duration and magnitude. Paradoxically, Interferon γ (IFNγ), a key cytokine for cellular immunity, can promote ICBT resistance. Using syngeneic mouse tumour models, we confirm that chronic IFNγ exposure confers resistance to immunotherapy targeting PD-1 (α-PD-1) in immunocompetent female mice. We observe upregulation of poly-ADP ribosyl polymerase 14 (PARP14) in chronic IFNγ-treated cancer cell models, in patient melanoma with elevated IFNG expression, and in melanoma cell cultures from ICBT-progressing lesions characterised by elevated IFNγ signalling. Effector T cell infiltration is enhanced in tumours derived from cells pre-treated with IFNγ in immunocompetent female mice when PARP14 is pharmacologically inhibited or knocked down, while the presence of regulatory T cells is decreased, leading to restoration of α-PD-1 sensitivity. Finally, we determine that tumours which spontaneously relapse in immunocompetent female mice following α-PD-1 therapy upregulate IFNγ signalling and can also be re-sensitised upon receiving PARP14 inhibitor treatment, establishing PARP14 as an actionable target to reverse IFNγ-driven ICBT resistance.
    MeSH term(s) Female ; Humans ; Animals ; Mice ; Immune Checkpoint Inhibitors/pharmacology ; Immune Checkpoint Inhibitors/therapeutic use ; Programmed Cell Death 1 Receptor ; Interferon-gamma ; Neoplasm Recurrence, Local ; Melanoma ; Disease Models, Animal ; Poly(ADP-ribose) Polymerases
    Chemical Substances Immune Checkpoint Inhibitors ; Programmed Cell Death 1 Receptor ; Interferon-gamma (82115-62-6) ; Poly(ADP-ribose) Polymerases (EC 2.4.2.30) ; PARP14 protein, human (EC 2.4.2.30)
    Language English
    Publishing date 2023-09-26
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2553671-0
    ISSN 2041-1723 ; 2041-1723
    ISSN (online) 2041-1723
    ISSN 2041-1723
    DOI 10.1038/s41467-023-41737-1
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