Somatic rearrangements causing oncogenic ectodomain deletions of FGFR1 in squamous cell lung cancer

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Abstract

The discovery of frequent 8p11-p12 amplifications in squamous cell lung cancer has fueled hopes that FGFR1, located inside this amplicon, might be a therapeutic target. In a clinical trial, only 11% of patients with 8p11 amplification (detected by FISH) responded to FGFR kinase inhibitor treatment. To understand the mechanism of FGFR1 dependency, we performed deep genomic characterization of 52 squamous cell lung carcinomas with 8p11-p12-amplification, including 10 tumors obtained from patients who had been treated with FGFR inhibitors. We discovered somatically altered variants of FGFR1 with deletion of exons 1-8 that resulted from intragenic tail-to-tail rearrangements. These ectodomain-deficient FGFR1 variants (ΔEC-FGFR1) were expressed in the affected tumors and tumorigenic in in-vitro and in-vivo. Mechanistically, Breakage-Fusion-Bridges were the source of 8p11-p12 amplification, resulting from frequent head-to-head and tail-to-tail rearrangements. However, only tumors with tail-to-tail rearrangements within or in close proximity upstream of FGFR1 exhibited FGFR1 dependency. Thus, the genomic events shaping the architecture of the 8p11-p12 amplicon provide a mechanistic explanation for the emergence of FGFR1-driven squamous cell lung cancer. Specifically, FGFR1 ectodomain deficient and FGFR1-centered amplifications caused by tail-to-tail rearrangements are novel somatic genomic event, which might be predictive of therapeutically relevant FGFR1 dependency.

Authors

Florian Malchers, Lucia Nogova, Martijn H. van Attekum, Lukas Maas, Johannes Brägelmann, Christoph Bartenhagen, Luc Girard, Graziella Bosco, Ilona Dahmen, Sebastian Michels, Clare E. Weeden, Andreas H. Scheel, Lydia Meder, Kristina Golfmann, Philipp Schuldt, Janna Siemanowski, Jan Rehker, Sabine Merkelbach-Bruse, Roopika Menon, Oliver Gautschi, Johannes M. Heuckmann, Elisabeth Brambilla, Marie-Liesse Asselin-Labat, Thorsten Persigehl, John D. Minna, Henning Walczak, Roland T. Ullrich, Matthias Fischer, Hans Christian Reinhardt, Juergen Wolf, Reinhard Büttner, Martin Peifer, Julie George, Roman K. Thomas

Suppression of food intake by Glp1r/Lepr-coexpressing neurons prevents obesity in mouse models

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Abstract

The adipose-derived hormone leptin acts via its receptor (LepRb) in the brain to control energy balance. A previously unidentified population of GABAergic hypothalamic LepRb neurons plays key roles in the restraint of food intake and body weight by leptin. To identify markers for candidate populations of LepRb neurons in an unbiased manner, we performed single-nucleus RNA-sequencing of enriched mouse hypothalamic LepRb cells, identifying several previously unrecognized populations of hypothalamic LepRb neurons. Many of these populations displayed strong conservation across species, including GABAergic Glp1r-expressing LepRb (LepRbGlp1r) neurons, which expressed more Lepr than other LepRb cell populations. Ablating Lepr from LepRbGlp1r cells provoked hyperphagic obesity without impairing energy expenditure. Similarly, improvements in energy balance by Lepr reactivation in GABA neurons of otherwise Lepr-null mice required Lepr expression in GABAergic Glp1r-expressing neurons. Furthermore, restoration of Glp1r expression in LepRbGlp1r neurons in otherwise Glp1r-null mice enabled food intake suppression by the GLP1R agonist, liraglutide. Thus, the conserved GABAergic LepRbGlp1r neuron population plays crucial roles in the suppression of food intake by leptin and GLP1R agonists.

Authors

Alan C Rupp, Abigail J. Tomlinson, Alison H. Affinati, Warren T. Yacawych, Allison M. Duensing, Cadence True, Sarah R. Lindsley, Melissa A. Kirigiti, Alexander J. MacKenzie, Joseph Polex-Wolf, Chien Li, Lotte B. Knudsen, Randy J. Seeley, David P. Olson, Paul Kievit, Martin G. Myers, Jr

RUNX1 loss renders hematopoietic and leukemic cells dependent on interleukin-3 and sensitive to JAK inhibition

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Abstract

Disease-initiating mutations in the transcription factor RUNX1 occur as germline and somatic events that cause leukemias with particularly poor prognosis. However, the role of RUNX1 in leukemogenesis is not fully understood and effective therapies for RUNX1-mutant leukemias remain elusive. Here, we use primary patient samples and a RUNX1 knockout model in primary human hematopoietic cells to investigate how RUNX1 loss contributes to leukemic progression and to identify targetable vulnerabilities. Surprisingly, we found that RUNX1 loss decreased proliferative capacity and stem cell function. However, RUNX1-deficient cells selectively upregulated the interleukin-3 (IL-3) receptor. Exposure to IL-3, but not other JAK/STAT cytokines, rescued RUNX1 KO proliferative and competitive defects. Further, we demonstrated that RUNX1 loss repressed JAK/STAT signaling and rendered RUNX1-deficient cells sensitive to JAK inhibitors. Our study identifies a dependency of RUNX1-mutant leukemias on IL-3/JAK/STAT signaling, which may enable these aggressive blood cancers to be targeted with existing agents.

Authors

Amy C. Fan, Yusuke Nakauchi, Lawrence Bai, Armon Azizi, Kevin A. Nuno, Feifei Zhao, Thomas Köhnke, Daiki Karigane, David Cruz-Hernandez, Andreas Reinisch, Purvesh Khatri, Ravindra Majeti

Rescue of alveolar wall liquid secretion blocks fatal lung injury by influenza-staphylococcal coinfection

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Abstract

Secondary lung infection by inhaled Staphylococcus aureus (SA) is a common and lethal event in individuals infected with influenza A virus (IAV). How IAV disrupts host defense to promote SA infection in lung alveoli, where fatal lung injury occurs, is not known. We addressed this issue using the first real-time determinations of alveolar responses to IAV in live, intact, perfused lungs. Our findings show IAV infection blocked defensive alveolar wall liquid (AWL) secretion and induced airspace liquid absorption, thereby reversing normal alveolar liquid dynamics and inhibiting alveolar clearance of inhaled SA. Loss of AWL secretion resulted from inhibition of the cystic fibrosis transmembrane conductance regulator (CFTR) ion channel in the alveolar epithelium, and airspace liquid absorption was caused by stimulation of the alveolar epithelial Na+ channel (ENaC). Loss of AWL secretion promoted alveolar stabilization of inhaled SA, but rescue of AWL secretion protected against alveolar SA stabilization and fatal SA-induced lung injury in IAV-infected mice. These findings reveal a central role for AWL secretion in alveolar defense against inhaled SA and identify AWL inhibition as a critical mechanism of IAV lung pathogenesis. AWL rescue may represent a new therapeutic approach for IAV-SA coinfection.

Authors

Stephanie Tang, Ana Cassandra De Jesus, Deebly Chavez, Sayahi Suthakaran, Sarah K.L. Moore, Keshon Suthakaran, Sonya Homami, Raveen Rathnasinghe, Alison J. May, Michael Schotsaert, Clemente J. Britto, Jahar Bhattacharya, Jaime L. Hook

Chronic kidney disease promotes atrial fibrillation via inflammasome pathway activation

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Abstract

Chronic kidney disease (CKD) is associated with a higher risk of atrial fibrillation (AF). The mechanistic link between CKD and AF remains elusive. Interleukin (IL)-1β, a main effector of ‘NLR-family pyrin domain-containing 3’ (NLRP3) inflammasome activation, is a key modulator of conditions associated with inflammation, such as AF and CKD. Circulating IL-1β levels were elevated in CKD-patients with AF vs CKD-patients in sinus rhythm. Moreover, NLRP3-activity was enhanced in atria of CKD-patients. To elucidate the role of NLRP3/IL-1β signaling in the pathogenesis of CKD-induced AF, wildtype (WT) and Nlrp3-/- mice were subjected to a two-stage subtotal nephrectomy protocol to induce CKD. 4-weeks post-surgery, IL-1β levels in serum and atrial tissue were increased in WT-CKD (vs WT-sham) mice. The increased susceptibility to pacing-induced AF and longer AF-duration in WT-CKD mice were associated with electrical remodeling, enlarged atria, and atrial fibrosis. Genetic inhibition of NLRP3 in Nlrp3-/- mice or neutralizing anti-IL-1β antibodies effectively reduced IL-1β-levels, normalized left atrial dimensions, reduced fibrosis and the AF-incidence. These data suggest that CKD creates a substrate for AF development by activating the NLRP3 inflammasome in atria, which is associated with structural and electrical remodeling. Neutralizing IL-1β antibodies may be beneficial for the prevention of CKD-induced AF.

Authors

Jia Song, Jose Alberto Navarro-Garcia, Jiao Wu, Arnela Saljic, Issam H. Abu-Taha, Luge Li, Satadru K. Lahiri, Joshua A. Keefe, Yuriana Aguilar-Sanchez, Oliver M. Moore, Yue Yuan, Xiaolei Wang, Markus Kamler, William E. Mitch, Gema Ruiz-Hurtado, Zhaoyong Hu, Sandhya S. Thomas, Dobromir Dobrev, Xander H.T. Wehrens, Na Li

Adverse outcomes in SARS-CoV-2 infected pregnant mice are gestational age-dependent and resolve with antiviral treatment

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Abstract

SARS-CoV-2 infection during pregnancy is associated with severe COVID-19 and adverse fetal outcomes, but the underlying mechanisms remain poorly understood. Moreover, clinical studies assessing therapeutics against SARS-CoV-2 in pregnancy are limited. To address these gaps, we developed a mouse model of SARS-CoV-2 infection during pregnancy. Outbred CD1 mice were infected at embryonic day (E) 6, E10, or E16 with a mouse adapted SARS-CoV-2 (maSCV2) virus. Outcomes were gestational age-dependent, with greater morbidity, reduced anti-viral immunity, greater viral titers, and impaired fetal growth and neurodevelopment occurring with infection at E16 (3rd trimester-equivalent) than with infection at either E6 (1st trimester-equivalent) or E10 (2nd trimester-equivalent). To assess the efficacy of ritonavir-boosted nirmatrelvir (recommended for pregnant individuals with COVID-19), we treated E16-infected dams with mouse equivalent doses of nirmatrelvir and ritonavir. Treatment reduced pulmonary viral titers, decreased maternal morbidity, and prevented offspring growth restriction and neurodevelopmental impairments. Our results highlight that severe COVID-19 during pregnancy and fetal growth restriction are associated with heightened virus replication in maternal lungs. Ritonavir-boosted nirmatrelvir mitigated maternal morbidity along with fetal growth and neurodevelopment restriction after SARS-CoV-2 infection. These findings prompt the need for further consideration of pregnancy in preclinical and clinical studies of therapeutics against viral infections.

Authors

Patrick S. Creisher, Jamie L. Perry, Weizhi Zhong, Jun Lei, Kathleen R. Mulka, W. Hurley Ryan, Ruifeng Zhou, Elgin H. Akin, Anguo Liu, Wayne Mitzner, Irina Burd, Andrew Pekosz, Sabra L. Klein

NLRP12 downregulates the Wnt/β-catenin pathway via interaction with STK38 to suppress colorectal cancer

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Abstract

Colorectal cancer (CRC) at advanced stages is rarely curable, underscoring the importance of exploring the mechanism of CRC progression and invasion. NOD-like receptor family member NLRP12 was shown to suppress colorectal tumorigenesis, but the precise mechanism was unknown. Here we demonstrate that invasive adenocarcinoma development in Nlrp12-deficient mice is associated with elevated expression of genes involved in proliferation, matrix degradation, and epithelial-to-mesenchymal transition (EMT). Signaling pathway analysis revealed higher activation of the Wnt/β-catenin pathway, but not NF-kB and MAPK pathways, in the Nlrp12-deficient tumors. Using Nlrp12 conditional knockout mice, we confirmed that NLRP12 regulates tumorigenesis, invasiveness, and β-catenin activation in an intestinal epithelial cell-specific manner. In corroboration, NLRP12 deficiency made CRC cells or organoids hyperproliferative. With proteomic studies, we identified STK38 as a novel interacting partner of NLRP12 involved in the inhibition of phosphorylation of GSK3β, leading to the degradation of β-catenin. Consistently, the expression of NLRP12 was significantly reduced while phospho-GSK3β and β-catenin were upregulated in mouse and human colorectal tumor tissues. In summary, NLRP12 is a potent negative regulator of the Wnt/β-catenin pathway, and the NLRP12-STK38-GSK3β signaling axis could be a promising therapeutic target for CRC.

Authors

Shahanshah Khan, Youn-Tae Kwak, Lan Peng, Shuiqing Hu, Brandi L. Cantarel, Cheryl M. Lewis, Yunpeng Gao, Ram S. Mani, Thirumala-Devi Kanneganti, Hasan Zaki

Anticancer pan-ErbB inhibitors reduce inflammation and tissue injury and exert broad-spectrum antiviral effects

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Abstract

Targeting host factors exploited by multiple viruses could offer broad-spectrum solutions for pandemic preparedness. Seventeen candidates targeting diverse functions emerged in a screen of 4,413 compounds for SARS-CoV-2 inhibitors. We demonstrated that lapatinib and other approved inhibitors of the ErbB family receptor tyrosine kinases suppress replication of SARS-CoV-2, Venezuelan equine encephalitis virus (VEEV), and other emerging viruses with a high barrier to resistance. Lapatinib suppressed SARS-CoV-2 entry and later stages of the viral life cycle and showed synergistic effect with the direct-acting antiviral nirmatrelvir. We discovered that ErbB1, 2 and 4 bind SARS-CoV-2 S1 protein and regulate viral and ACE2 internalization, and they are required for VEEV infection. In human lung organoids, lapatinib protected from SARS-CoV-2-induced activation of ErbB-regulated pathways implicated in non-infectious lung injury, pro-inflammatory cytokine production, and epithelial barrier injury. Lapatinib suppressed VEEV replication, cytokine production and disruption of the blood-brain barrier integrity in microfluidic-based human neurovascular units, and reduced mortality in a lethal infection murine model. We validated lapatinib-mediated inhibition of ErbB activity as an important mechanism of antiviral action. These findings reveal regulation of viral replication, inflammation, and tissue injury via ErbBs and establish a proof-of-principle for a repurposed, ErbB-targeted approach to combat emerging viruses.

Authors

Sirle Saul, Marwah Karim, Luca Ghita, Pei-Tzu Huang, Winston Chiu, Verónica Durán, Chieh-Wen Lo, Sathish Kumar, Nishank Bhalla, Pieter Leyssen, Farhang Alem, Niloufar A. Boghdeh, Do HoangNhu Tran, Courtney A. Cohen, Jacquelyn A. Brown, Kathleen E. Huie, Courtney Tindle, Mamdouh Sibai, Chengjin Ye, Ahmed Magdy Khalil, Kevin Chiem, Luis Martinez-Sobrido, John M. Dye, Benjamin A. Pinsky, Pradipta Ghosh, Soumita Das, David E. Solow-Cordero, Jing Jin, John P. Wikswo, Dirk Jochmans, Johan Neyts, Steven De Jonghe, Aarthi Narayanan, Shirit Einav

CFTR-rich ionocytes mediate chloride absorption across airway epithelia

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Abstract

The volume and composition of a thin layer of liquid covering the airway surface defend the lung from inhaled pathogens and debris. Airway epithelia secrete Cl– into the airway surface liquid through CFTR (cystic fibrosis transmembrane conductance regulator) channels, thereby increasing the volume of airway surface liquid. The discovery that pulmonary ionocytes contain high levels of CFTR led us to predict that ionocytes drive secretion. However, we found the opposite. Elevating ionocyte abundance increased liquid absorption, whereas reducing ionocyte abundance increased secretion. In contrast to other airway epithelial cells, ionocytes contained barttin/Cl– channels in their basolateral membrane. Disrupting barttin/Cl– channel function impaired liquid absorption, and overexpressing barttin/Cl– channels increased absorption. Together, apical CFTR and basolateral barttin/Cl– channels provide an electrically conductive pathway for Cl– flow through ionocytes, and the transepithelial voltage generated by apical Na+ channels drives absorption. These findings indicate that ionocytes mediate liquid absorption, and secretory cells mediate liquid secretion. Segregating these counteracting activities to distinct cell types enables epithelia to precisely control the airway surface. Moreover, the divergent role of CFTR in ionocytes and secretory cells suggests that cystic fibrosis disrupts both liquid secretion and absorption.

Authors

Lei Lei, Soumba Traore, Guillermo S. Romano Ibarra, Philip H. Karp, Tayyab Rehman, David K. Meyerholz, Joseph Zabner, David A. Stoltz, Patrick L. Sinn, Michael J. Welsh, Paul B. McCray, Jr., Ian M. Thornell

Nucleus accumbens D1/D2 circuits control opioid withdrawal symptoms in mice

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Abstract

The nucleus accumbens (NAc) is the most promising target for drug use disorder treatment. Deep brain stimulation (DBS) of NAc is effective for drug use disorder treatment. However, the mechanisms by which DBS produces its therapeutic effects remain enigmatic. Here, we define a behavioral cut-off criterion to distinguish depressive-like behaviors and nondepressive-like behaviors in mice after morphine withdrawal. We identified a basolateral amygdala (BLA) to NAc D1 medium spiny neuron (D1 MSN) pathway that controls depressive-like behaviors after morphine withdrawal. Furthermore, the paraventricular nucleus of thalamus (PVT) to NAc D2 MSN pathway that controls naloxone-induced acute withdrawal symptoms. Optogenetic-induced long-term potentiation with kappa-opioid receptor (KOR) antagonism enhanced BLA to NAc D1 MSN signaling and also altered the excitation/inhibition balance of NAc D2 MSN signaling. We also verified that a new 50 Hz DBS protocol reversed morphine withdrawal-evoked abnormal plasticity in NAc. Importantly, this refined DBS treatment effectively alleviated naloxone-induced withdrawal symptoms and depressive-like behaviors and prevented stress-induced reinstatement. Taken together, the results demonstrated that input- and cell type-specific synaptic plasticity underlies morphine withdrawal, which may lead to novel targets for the treatment of opioid use disorder.

Authors

Yongsheng Zhu, Kejia Wang, Tengfei Ma, Yuanyuan Ji, Yin Lou, Xiaoyu Fu, Ye Lu, Yige Liu, Wei Dang, Qian Zhang, Fangyuan Yin, Kena Wang, Bing Yu, Hongbo Zhang, Jianghua Lai, Yunpeng Wang