Protective role for kidney TREM2high macrophages in obesity- and diabetes-induced kidney injury

Diabetic kidney disease (DKD), the most common cause of kidney failure, is a frequent complication of diabetes and obesity, and yet to date, treatments to halt its progression are lacking. We analyze kidney single-cell transcriptomic profiles from DKD patients and two DKD mouse models at multiple time points along disease progression-high-fat diet (HFD)-fed mice aged to 90-100 weeks and BTBR ob/ob mice (a genetic model)-and report an expanding population of macrophages with high expression of triggering receptor expressed on myeloid cells 2 (TREM2) in HFD-fed mice. TREM2high macrophages are enriched in obese and diabetic patients, in contrast to hypertensive patients or healthy controls in an independent validation cohort. Trem2 knockout mice on an HFD have worsening kidney filter damage and increased tubular epithelial cell injury, all signs of worsening DKD. Together, our studies suggest that strategies to enhance kidney TREM2high macrophages may provide therapeutic benefits for DKD.

Abstract PO-093: Evaluating dependencies by rapid image-based ex vivo cancer biosensors

Successful mapping of cancer dependencies requires conducting genetic and drug screens on a diversity of models. However, the difficulty in generating long-term models of many cancers limits the share of patient samples that can be studied. Such long-term models have likely also lost the cellular heterogeneity present in the original tumor due to in vitro propagation. To overcome these limitations, we are developing image-based ex vivo cancer biosensors from early patient material. Using freshly received gastroesophageal cancer ascites, we are optimizing perturbation methods and utilizing single-cell transcriptomics and label-free microscopy to infer a subpopulation-specific vulnerability profile. We show that label-free microscopy can infer cell identity and viability in heterogeneous early patient samples. Additionally, early drug perturbation recapitulates observations made in established gastroesophageal cancer organoids. Successful implementation of ex vivo biosensors will expand the cancer dependency space by making perturbational studies accessible to more diverse samples, and by identifying and validating hits in a more immediate setting to the original tumor.

Citation Format: Mushriq Al-Jazrawe, Csaba Molnar, Niklas Rindtorff, Pinar Eser, Sean Misek, Maria Alimova, Oana Ursu, William Colgan, Adel Attari, Natalie Tsang, Paula Keskula, Carmen Rios, Moony Tseng, Anne Carpenter, James McFarland, Adam Bass, Samuel Klempner, Jesse Boehm. Evaluating dependencies by rapid image-based ex vivo cancer biosensors [abstract]. In: Proceedings of the AACR Virtual Special Conference on Artificial Intelligence, Diagnosis, and Imaging; 2021 Jan 13-14. Philadelphia (PA): AACR; Clin Cancer Res 2021;27(5_Suppl):Abstract nr PO-093.

A High Content Screen for Mucin-1-Reducing Compounds Identifies Fostamatinib as a Candidate for Rapid Repurposing for Acute Lung Injury during the COVID-19 pandemic

Drug repurposing is the only method capable of delivering treatments on the shortened time-scale required for patients afflicted with lung disease arising from SARS-CoV-2 infection. Mucin-1 (MUC1), a membrane-bound molecule expressed on the apical surfaces of most mucosal epithelial cells, is a biochemical marker whose elevated levels predict the development of acute lung injury (ALI) and respiratory distress syndrome (ARDS), and correlate with poor clinical outcomes. In response to the pandemic spread of SARS-CoV-2, we took advantage of a high content screen of 3,713 compounds at different stages of clinical development to identify FDA-approved compounds that reduce MUC1 protein abundance. Our screen identified Fostamatinib (R788), an inhibitor of spleen tyrosine kinase (SYK) approved for the treatment of chronic immune thrombocytopenia, as a repurposing candidate for the treatment of ALI. In vivo , Fostamatinib reduced MUC1 abundance in lung epithelial cells in a mouse model of ALI. In vitro , SYK inhibition by Fostamatinib promoted MUC1 removal from the cell surface. Our work reveals Fostamatinib as a repurposing drug candidate for ALI and provides the rationale for rapidly standing up clinical trials to test Fostamatinib efficacy in patients with COVID-19 lung injury.

Abstract B48: Identification of potent, cell active MTH1 inhibitors and their use in target validation studies

MTH1 is a protein that sanitizes oxidized dNTPs in the cell. It preferentially hydrolyzes 8-oxo-dGTP and 2-OH-dATP to their corresponding monophosphates and thereby prevents the incorporation of oxidized nucleotides into DNA or RNA. The functional result is a reduction in down-stream mutations, or DNA damage, thus preventing cell death. Recent publications suggest that MTH1 is a non-essential enzyme in normal cells, but is required for the survival of cancer cells as a consequence of being subjected to high levels of oxidative stress; hence its relevance as an oncology target. Gad et al., 2014

The interesting target rationale combined with a perceived high chemical tractability of the target resulting from availability of x-ray crystallographic information for the protein, led to a decision to undertake, in parallel, target validation, assay development and drug discovery. This effort resulted in the structure-based design of potent, cell active MTH1 small molecule inhibitors. This poster will describe the discovery and optimization of these inhibitors, and their use to evaluate the potential of MTH1 as an oncology target. This work was complemented by parallel genetic studies. Pharmacodynamic evaluation of target engagement using proximal biomarkers will be presented, as will phenotypic responses across a range of cancer cell lines.

Citation Format: Elisabetta Leo, Alessia Petrocchi, Jennifer Bardenhagen, Maria Alimova, Xi Shi, Connor Parker, Naphtali Reyna, Matthew Hamilton, Edward Felix, Andrzej Mazan, Christian Dillon, Faika Mseeh, Joseph R. Marszalek, Carlo Toniatti, Giulio Draetta, Phil Jones, Richard T. Lewis. Identification of potent, cell active MTH1 inhibitors and their use in target validation studies. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr B48.

Abstract LB-A15: IACS-010759 is a novel inhibitor of oxidative phosphorylation that selectively targets AML cells by inducing a metabolic catastrophe

Acute myeloid leukemia (AML) is a highly aggressive disease with a high mortality rate that encompasses several genetically and clinically diverse hematological malignancies characterized by clonal expansion of transformed stem/progenitor cells with limited ability to differentiate into mature blood cells. Standard of care for AML has progressed minimally in the past 30 years for relapse/refractory AML, with survival rates of <12% for those aged >65 years. Therefore, novel, highly effective therapeutics are needed for this population. Targeting bioenergetic susceptibilities is an exciting area of oncology therapeutics that is potentially applicable in AML. Our group and others have shown that AML blasts depend significantly on mitochondrial oxidative phosphorylation to meet their energy and biomass production demands. Through an extensive medicinal chemistry campaign IACS-10759 was identified as a potent, selective inhibitor of complex I of the electron transport chain with excellent PK and a suitable overall profile. In AML cell lines and primary AML blasts treated ex vivo, we observe a robust decrease in proliferation and a concomitant increase in apoptosis with EC50 values of less than 10 nM. Response to IACS-10759 in AML cells was associated with induction of a metabolic catastrophe that negatively impacted the cells' ability to sustain energy homeostasis, amino acid biosynthesis, and nucleotide production. In a primary AML patient derived xenograft model from a patient who was refractory to standard of care and salvage therapies, 42 days of IACS-10759 (QDx5/week) treatment at 10 mg/kg extended the median survival by greater than 2-fold. Inhibition of OXPHOS by IACS-10759 was confirmed in AML cell lines and PDX models by a decrease in oxygen consumption and significant changes in gene and protein expression, non-essential amino acids and nucleotides. Due to the robust response in AML cell lines, primary AML samples ex vivo, and in vivo efficacy in primary AML PDX models, IACS-10759 has been advanced through IND enabling studies with first-in-human studies targeted for the second quarter of 2016.

Citation Format: Jennifer R. Molina, Marina Protopopova, Madhavi Bandi, Jennifer Bardenhagen, Christopher Bristow, Maria Alimova, Christopher Carroll, Edward Chang, Ningping Feng, Jason Gay, Mary Geck Do, Jennifer Greer, Sha Huang, Yongying Jiang, Marina Konopleva, Polina Matre, Zhijun Kang, Gang Liu, Timothy McAfoos, Pietro Morlacchi, Melinda Smith, Sonal Sonal, Jay Theroff, Quanyun Xu, Giulio Draetta, Philip Jones, Carlo Toniatti, M. Emilia Di Francesco, Joseph R. Marszalek. IACS-010759 is a novel inhibitor of oxidative phosphorylation that selectively targets AML cells by inducing a metabolic catastrophe. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr LB-A15.