Targeted therapies such as venetoclax (Bcl-2 inhibitor) have revolutionized the treatment of chronic lymphocytic leukemia (CLL). We previously reported that persister CLL cells in treated patients overexpress multiple anti-apoptotic proteins and display resistance to pro-apoptotic agents. Here, we demonstrated that multidrug resistant CLL cells in vivo exhibit apoptosis restriction at a premitochondrial level due to insufficient activation of the Bax and Bak proteins. Co-immunoprecipitation analyses with selective BH-domain antagonists revealed that the pleotropic pro-apoptotic protein (Bim) is prevented from activating Bax/Bak by “switching” interactions to other upregulated anti-apoptotic proteins (Mcl-1/Bcl-xL/Bcl-2). Hence, treatments that bypass Bax/Bak restriction are required to deplete these resistant cells in patients. Protein Phosphatase 2A (PP2A) contributes to oncogenesis and treatment resistance. We observed that a small molecule activator of PP2A (SMAP) induced cytotoxicity in multiple cancer cell lines and CLL samples, including multidrug resistant leukemia/lymphoma cells. The SMAP (DT-061) activated apoptosis in multidrug resistant CLL cells through induction of mitochondrial permeability transition pores (mPTP), independent of Bax/Bak. DT-061 inhibited the growth of wild type and Bax/Bak double knockout multidrug resistant CLL cells in a xenograft mouse model. Collectively, we discovered multidrug resistant CLL cells in patients, and validated a pharmacologically tractable pathway to deplete this reservoir.
Kallesh D. Jayappa, Brian Tran, Vicki L. Gordon, Christopher G. Morris, Shekhar Saha, Caroline C. Farrington, Caitlin M. O’Connor, Kaitin P. Zawacki, Krista M. Isaac, Mark Kester, Timothy P. Bender, Michael E. Williams, Craig A. Portell, Michael J. Weber, Goutham Narla
BACKGROUND. Adoptive transfer of EBV-specific T cells can restore specific immunity in immunocompromised patients with EBV-associated complications. METHODS. We provide results of a personalized T-cell manufacturing program evaluating donor, patient, T-cell product and outcome data. Patient-tailored clinical-grade EBV-specific cytotoxic T-lymphocyte (EBV-CTL) products from stem cell donors (SCD), related third party donors (TPD) or unrelated TPD from the allogeneic T-cell donor registry (alloCELL) established at Hannover Medical School were manufactured by immunomagnetic selection using CliniMACS Plus or Prodigy device and EBV PepTivators EBNA-1 and Select. Consecutive manufacturing processes were evaluated and patient outcome and side effects were retrieved by retrospective chart analysis. RESULTS. Forty clinical-grade EBV-CTL products from SCDs, related or unrelated TPDs were generated for 37 patients with and without transplantation (Tx) history within 5 days (median) after donor identification. 34 patients received 1-14 EBV-CTL products (fresh and cryopreserved). EBV-CTL transfer led to complete response in 20 of 29 patients who were evaluated for clinical response. No infusion-related toxicity was reported. EBV-specific T cells in patients’ blood were detectable in 16/18 monitored patients (89 %) after transfer and correlated with clinical response. CONCLUSION. In conclusion, personalized clinical-grade manufacturing of EBV-CTL products via immunomagnetic selection from SCD, related or unrelated TPD is feasible in a timely manner. Overall, EBV-CTL were clinically effective and well-tolerated. Our data suggest EBV-CTL as promising therapeutic approach for immunocompromised patients with refractory EBV-associated diseases beyond HSCT as well as patients with pre-existing organ dysfunction. TRIAL REGISTRATION. Not applicable. FUNDING. This study was in part funded by the German Research Foundation (DFG, 158989968/SFB 900), the Deutsche Kinderkrebsstiftung (DKS 2013.09), the Wilhelm-Sander-Stiftung (http://www.wilhelm-sander-stiftung.de, 2015.097.1), the Ellen-Schmidt-Program of the Hannover Medical School, and the German Federal Ministry of Education and Research (reference number: 01EO0802).
Agnes Bonifacius, Britta Lamottke, Sabine Tischer-Zimmermann, Rebecca Schultze-Florey, Lilia Goudeva, Hans-Gert Heuft, Lubomir Arseniev, Rita Beier, Gernot Beutel, Gunnar Cario, Birgit Fröhlich, Johann Greil, Leo Hansmann, Justin Hasenkamp, Michaela Höfs, Patrick Hundsdoerfer, Edgar Jost, Kinan Kafa, Oliver Kriege, Nicolaus Kröger, Stephan Mathas, Roland Meisel, Michaela Nathrath, Mervi Putkonen, Sarina Ravens, Hans Christian Reinhardt, Elisa Sala, Martin G. Sauer, Clemens Schmitt, Roland Schroers, Nina Kristin Steckel, Ralf Ulrich Trappe, Mareike Verbeek, Daniel Wolff, Rainer Blasczyk, Britta Eiz-Vesper, Britta Maecker-Kolhoff
Ras plays an essential role in the development of acinar to ductal metaplasia (ADM) and pancreatic ductal adenocarcinoma (PDAC). However, mutant Kras is an inefficient driver for PDAC development. The switching mechanisms from low Ras activity to high Ras activity that is required for development and progression of pancreatic intraepithelial neoplasia (PanIN) are unclear. In this study, we found that HPK1 was upregulated during pancreatic injury and ADM. HPK1 interacted with the SH3 domain and phosphorylated Ras GTPase activating protein (RasGAP) and upregulated RasGAP activity. Using the transgenic mouse models of HPK1 or M46, a kinase-dead mutant of HPK1, we showed that HPK1 inhibited Ras activity and its downstream signaling and regulated acinar cell plasticity. M46 promoted the development of ADM and PanINs. Expression of M46 in KrasG12D;Bac mice promoted the infiltration of myeloid-derived suppressor cells and macrophages, inhibited the infiltration of T cells, and accelerated the progression of PanINs to invasive and metastatic PDAC, while HPK1 attenuated mutant Kras-driven PanIN progression. Our results showed that HPK1 plays an important role in ADM and the progression of PanINs by regulating Ras signaling. Loss of HPK1 kinase activity promotes an immunosuppressive tumor microenvironment and accelerates the progression of PanINs to PDAC.
Hua Wang, Rohan Moniruzzaman, Lei Li, Baoan Ji, Yi Liu, Xiangsheng Zuo, Reza Abbasgholizadeh, Jun Zhao, Guangchao Liu, Ruiqi Wang, Hongli Tang, Ryan Sun, Xiaoping Su, Tse-Hua Tan, Anirban Maitra, Huamin Wang
Neurofibromatosis Type 1 (NF1) is one of the most common tumor-predisposing genetic disorders. Neurofibromas are NF1-associated benign tumors. A hallmark feature of neurofibromas is an abundant collagen-rich extracellular matrix (ECM) that constitutes >50% of the tumor dry weight. However, little is known about the mechanism underlying ECM deposition during neurofibroma development and treatment response. We performed a systematic investigation of ECM enrichment during plexiform neurofibroma (pNF) development, and identified basement membrane (BM) proteins, rather than major collagen isoforms, as the most upregulated ECM component. Following MEK inhibitor treatment, the ECM profile displayed an overall down-regulation signature, suggesting ECM reduction as a therapeutic benefit of MEK inhibition. Through these proteomic studies, TGF-β1 signaling was identified as playing a role in ECM dynamics. Indeed, TGF-β1 overexpression promoted pNF progression in vivo. Furthermore, by integrating single-cell RNA-sequencing, we found that immune cells including macrophages and T cells produce TGF-β1 to induce Schwann cells to produce and deposit BM proteins for ECM remodeling. Following Nf1 loss, neoplastic Schwann cells further increased BM protein deposition in response to TGF-β1. Our data delineate the regulation governing ECM dynamics in pNF and suggest that BM proteins could serve as markers for disease diagnosis and treatment response.
Chunhui Jiang, Ashwani Kumar, Ze Yu, Tracey Shipman, Yong Wang, Renee M. McKay, Chao Xing, Lu Q. Le
Pablo Canales-Herrerias, Yolanda Garcia-Carmona, Joan Shang, Hadar Meringer, Debra S. Yee, Lin Radigan, Sofija Buta, Gustavo Martinez-Delgado, Michael Tankelevich, Drew S. Helmus, Marla Dubinksy, Annelie Everts-van der Wind, Thierry Dervieux, Dusan Bogunovic, Jean-Frederic Colombel, Jason M. Brenchley, Jeremiah Faith, Charlotte Cunningham-Rundles, Andrea Cerutti, Saurabh Mehandru
Patients with Autosomal Recessive Microcephaly 15 caused by deficiency in the sodium-dependent lysophosphatidylcholine (LPC) transporter Major Facilitator Superfamily Domain containing 2a (Mfsd2a) present with both microcephaly and hypomyelination, suggesting an important role of LPC uptake by oligodendrocytes in the process of myelination. Here, we demonstrate that Mfsd2a is specifically expressed in oligodendrocyte precursor cells (OPC) and is critical for oligodendrocyte development. Single cell sequencing of the oligodendrocyte lineage revealed that OPCs from OPC-specific Mfsd2a KO mice (2aOKO) underwent precocious differentiation into immature oligodendrocytes (iOLs) and impaired maturation into myelinating oligodendrocytes, correlating with postnatal brain hypomyelination. 2aOKO mice did not exhibit microcephaly, consistent with microcephaly being consequential to absence of LPC uptake at the blood-brain barrier and not from deficiency in OPCs. Lipidomic analysis showed that OPCs and iOLs from 2aOKO mice had significantly decreased phospholipids containing omega-3 fatty acids with an opposite increase in unsaturated fatty acids, that latter being products of de novo synthesis governed by Srebp-1. RNA sequencing indicated activation of the Srebp-1 pathway and defective expression of regulators of oligodendrocyte development. Taken together, these findings indicate that the transport of LPCs by Mfsd2a in OPCs is important for maintaining OPC cell state to regulate postnatal brain myelination.
Vetrivel Sengottuvel, Monalisa Hota, Jeongah Oh, Dwight L. Galam, Bernice H. Wong, Markus R. Wenk, Sujoy Ghosh, Federico Torta, David L. Silver
Although a disease-modifying therapy for CLN2 disease now exists, a poor understanding of cellular pathophysiology has hampered the development of more effective and persistent therapies. Here, we investigated the nature and progression of neurological and underlying neuropathological changes in Cln2R207X mice, which carry one of the most common pathogenic mutations in human patients, but are yet to be fully characterized. Long-term electroencephalography recordings revealed progressive epileptiform abnormalities including spontaneous seizures, providing a robust and quantifiable disease-relevant phenotype. These seizures were accompanied by the loss of multiple cortical neuron populations, including those stained for interneuron markers. Further histological analysis revealed early localized microglial activation months before neuron loss started in the thalamocortical system and spinal cord, which was accompanied by astrogliosis. This pathology was more pronounced and occurred in the cortex before the thalamus or spinal cord, and differs markedly from the staging seen in mouse models of other forms of NCL. Neonatal administration of adeno-associated virus 9 (AAV9)-mediated gene therapy ameliorated the seizure and gait phenotypes and prolonged the lifespan of Cln2R207X mice, attenuating most pathological changes. Our findings highlight the importance of clinically relevant outcome measures for judging pre-clinical efficacy of therapeutic interventions for CLN2 disease.
Keigo Takahashi, Elizabeth M. Eultgen, Sophie H. Wang, Nicholas R. Rensing, Hemanth R. Nelvagal, Joshua T. Dearborn, Olivier Danos, Nicholas Buss, Mark S. Sands, Michael Wong, Jonathan D. Cooper
Patients with severe COVID-19 develop acute respiratory distress syndrome (ARDS) that may progress to cytokine storm syndrome, organ dysfunction, and death. Considering that complement component 5a (C5a), through its cellular receptor C5aR1, has potent proinflammatory actions, and plays immunopathological roles in inflammatory diseases, we investigated whether C5a/C5aR1 pathway could be involved in COVID-19 pathophysiology. C5a/C5aR1 signaling increased locally in the lung, especially in neutrophils of critically ill COVID-19 patients compared to patients with influenza infection, as well as in the lung tissue of K18-hACE2 Tg mice (Tg mice) infected with SARS-CoV-2. Genetic and pharmacological inhibition of C5aR1 signaling ameliorated lung immunopathology in Tg-infected mice. Mechanistically, we found that C5aR1 signaling drives neutrophil extracellular trap (NET)s-dependent immunopathology. These data confirm the immunopathological role of C5a/C5aR1 signaling in COVID-19 and indicate that antagonists of C5aR1 could be useful for COVID-19 treatment.
Bruna M.S. Silva, Giovanni F. Gomes, Flavio P. Veras, Seppe Cambier, Gabriel V.L. Silva, Andreza U. Quadros, Diego B. Caetité, Daniele C. Nascimento, Camila M.S. Silva, Juliana C. Costa Silva, Samara Damasceno, Ayda H. Schneider, Fabio Beretta, Sabrina S. Batah, Icaro M.S. Castro, Isadora M. Paiva, Tamara Rodrigues, Ana Salina, Ronaldo Martins, Guilherme C. Martelossi Cebinelli, Naira L. Bibo, Daniel Macedo de Melo Jorge, Helder I. Nakaya, Dario S. Zamboni, Luiz O. Leiria, Alexandre T. Fabro, José C. Alves-Filho, Eurico Arruda, Paulo Louzada-Junior, Renê D.R. Oliveira, Larissa D. Cunha, Pierre Van Mol, Lore Vanderbeke, Simon Feys, Els Wauters, Laura Brandolini, Andrea Aramini, Fernando Q. Cunha, Jörg Köhl, Marcello Allegretti, Diether Lambrechts, Joost Wauters, Paul Proost, Thiago M. Cunha
BACKGROUND. Despite guidelines promoting the prevention and aggressive treatment of ventilator-associated pneumonia (VAP), the importance of VAP as a driver of outcomes in mechanically ventilated patients, including patients with severe COVID-19, remains unclear. We aimed to determine the contribution of unsuccessful treatment of VAP to mortality in patients with severe pneumonia. METHODS. We performed a single-center prospective cohort study of 585 mechanically ventilated patients with severe pneumonia and respiratory failure, 190 of whom had COVID-19, who underwent at least one bronchoalveolar lavage. A panel of ICU physicians adjudicated pneumonia episodes and endpoints based on clinical and microbiologic data. Given the relatively long ICU length of stay among patients with COVID-19, we developed a machine learning approach called CarpeDiem, which groups similar ICU patient-days into clinical states based on electronic health record data. RESULTS.CarpeDiem revealed that the long ICU length of stay among patients with COVID-19 is attributable to long stays in clinical states characterized primarily by respiratory failure. While VAP was not associated with mortality overall, mortality was higher in patients with one episode of unsuccessfully treated VAP compared with successfully treated VAP (76.4% versus 17.6%, P < 0.001). In all patients, including those with COVID-19, CarpeDiem demonstrated that unresolving VAP was associated with transitions to clinical states associated with higher mortality. CONCLUSIONS. Unsuccessful treatment of VAP is associated with greater mortality. The relatively long length of stay among patients with COVID-19 is primarily due to prolonged respiratory failure, placing them at higher risk of VAP. FUNDING. U19AI135964
Catherine A. Gao, Nikolay S. Markov, Thomas Stoeger, Anna E. Pawlowski, Mengjia Kang, Prasanth Nannapaneni, Rogan A. Grant, Chiagozie Pickens, James M. Walter, Jacqueline M. Kruser, Luke V. Rasmussen, Daniel Schneider, Justin Starren, Helen K. Donnelly, Alvaro Donayre, Yuan Luo, G.R. Scott Budinger, Richard G. Wunderink, Alexander V. Misharin, Benjamin D. Singer
Seizures are a frequent complication of adult-type diffuse gliomas, and are often difficult to control with medications. Gliomas with mutations in isocitrate dehydrogenase 1 or 2 (IDHmut) are more likely than IDH wild-type (IDHwt) gliomas to cause seizures as part of their initial clinical presentation. However, whether IDHmut is also associated with seizures during the remaining disease course, and whether IDHmut inhibitors can reduce seizure risk, are unclear. Clinical multivariable analyses showed that preoperative seizures, glioma location, extent of resection, and glioma molecular subtype (including IDHmut status) all contribute to postoperative seizure risk in adult-type diffuse glioma patients, and that postoperative seizures are often associated with tumor recurrence. Experimentally, the metabolic product of IDHmut, D-2-hydroxyglutarate, rapidly synchronizes neuronal spike firing in a seizure-like manner, but only when nonneoplastic glial cells are present. In vitro and in vivo models can recapitulate IDHmut glioma-associated seizures, and IDHmut inhibitors currently being evaluated in glioma clinical trials inhibit seizures in those models, independent of their effects on glioma growth. These data show that postoperative seizure risk in adult-type diffuse gliomas varies in large part by molecular subtype, and that IDHmut inhibitors could play a key role in mitigating such risk in IDHmut glioma patients.
Michael Drumm, Wenxia Wang, Thomas K. Sears, Kirsten Bell-Burdett, Rodrigo Javier, Kristen Y. Cotton, Brynna T. Webb, Kayla T. Byrne, Dusten Unruh, Vineeth Thirunavu, Jordain Walshon, Alicia Steffens, Kathleen McCortney, Rimas V. Lukas, Joanna J. Phillips, Esraa Mohamed, John D. Finan, Lucas Santana-Santos, Amy B. Heimberger, Colin K. Franz, Jonathan E. Kurz, Jessica W. Templer, Geoffrey T. Swanson, Craig Horbinski
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