Blocking expression of inhibitory receptor NKG2A overcomes tumor resistance to NK cells

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Abstract

A key mechanism of tumor resistance to immune cells is mediated by expression of peptide-loaded HLA-E in tumor cells, which suppresses natural killer (NK) cell activity via ligation of the NK inhibitory receptor CD94/NKG2A. Gene expression data from approximately 10,000 tumor samples showed widespread HLAE expression, with levels correlating with those of KLRC1 (NKG2A) and KLRD1 (CD94). To bypass HLA-E inhibition, we developed a way to generate highly functional NK cells lacking NKG2A. Constructs containing a single-chain variable fragment derived from an anti-NKG2A antibody were linked to endoplasmic reticulum-retention domains. After retroviral transduction in human peripheral blood NK cells, these NKG2A Protein Expression Blockers (PEBLs) abrogated NKG2A expression. The resulting NKG2Anull NK cells had higher cytotoxicity against HLA-E-expressing tumor cells. Transduction of anti-NKG2A PEBL produced more potent cytotoxicity than interference with an anti-NKG2A antibody and prevented de novo NKG2A expression, without affecting NK cell proliferation. In immunodeficient mice, NKG2Anull NK cells were significantly more powerful than NKG2A+ NK cells against HLA-E-expressing tumors. Thus, NKG2A downregulation evades the HLA-E cancer immune-checkpoint, and increases the anti-tumor activity of NK cell infusions. Because this strategy is easily adaptable to current protocols for clinical-grade immune cell processing, its clinical testing is feasible and warranted.

Authors

Takahiro Kamiya, See Voon Seow, Desmond Wong, Murray Robinson, Dario Campana

Innate gene signature distinguishes humoral versus cytotoxic responses to influenza vaccination

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Abstract

Background: Systems vaccinology allows cutting-edge analysis of innate biomarkers of vaccine efficacy. We have been exploring novel strategies to shape the adaptive immune response, by targeting innate immune cells through novel immunization routes. Methods: This randomized phase I/II clinical study (n=60 healthy subjects aged 18-45 years old) used transcriptomic analysis to discover early biomarkers of immune response quality after transcutaneous (t.c.), intradermal (i.d.), and intramuscular (i.m.) administration of a trivalent influenza vaccine (TIV season 2012-2013) (1:1:1 ratio). Safety and immunogenicity (hemagglutinin inhibition (HI), microneutralization (MN) antibodies and CD4, CD8 effector T cells) were measured at baseline Day (D)0 and at D21. Blood transcriptome was analyzed at D0 and D1. Results: TIV-specific CD8+GranzymeB+(GRZ) T cells appeared in more individuals immunized by the t.c. and i.d. routes, while immunization by the i.d. and i.m. routes prompted high levels of HI antibody titers and MN against A/H1N1 and A/H3N2 influenza viral strains. The early innate gene signature anticipated immunological outcome by discriminating two clusters of individuals with either distinct humoral or CD8 cytotoxic responses. Several pathways explained this dichotomy confirmed by nine genes and serum level of CXCL10 were correlated with either TIV-specific cytotoxic CD8+GRZ+ T-cell or antibody responses. A logistic regression analysis demonstrated that these nine genes and serum levels of CXCL10 (D1/D0) best foreseen TIV-specific CD8+GRZ+ T-cell and antibody responses at D21. Conclusion: This study provides new insight into the impact of immunization routes and innate signature in the quality of adaptive immune responses.

Authors

Eléna Gonçalves, Olivia Bonduelle, Angèle Soria, Pierre Loulergue, Alexandra Rousseau, Marine Cachanado, Henri Bonnabau, Rodolphe Thiebaut, Nicolas Tchitchek, Sylvie Behillil, Sylvie van der Werf, Annika Vogt, Tabassome Simon, Odile Launay, Behazine Combadière

Profound MEK inhibitor response in a cutaneous melanoma harboring a GOLGA4-RAF1 fusion

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Abstract

BRAF and CRAF are critical components of the MAPK signaling pathway which is activated in many cancer types. In approximately 1% of melanomas, BRAF or CRAF are activated through structural arrangements. We describe here a metastatic melanoma with a GOLGA4-RAF1 fusion and pathogenic variants in CTNNB1 and CDKN2A. Anti-CTLA4/anti-PD1 combination immunotherapy failed to control tumor progression. In the absence of other actionable variants the patient was administered MEK inhibitor therapy on the basis of its potential action against RAF1 fusions. This resulted in a profound and clinically significant response. We demonstrated that GOLGA4-RAF1 expression was associated with ERK activation, elevated expression of the RAS/RAF downstream co-effector ETV5, and a high Ki67 index. These findings provide a rationale for the dramatic response to targeted therapy. This study shows that thorough molecular characterization of treatment-resistant cancers can identify therapeutic targets and personalize management, leading to improved patient outcomes.

Authors

Christopher R. McEvoy, Huiling Xu, Kortnye Smith, Dariush Etemadmoghadam, Huei San Leong, David Y. Choong, David J. Byrne, Amir Iravani, Sophie Beck, Linda Mileshkin, Richard W. Tothill, David D. Bowtell, Bindi M. Bates, Violeta Nastevski, Judy Browning, Anthony H. Bell, Chloe Khoo, Jayesh Desai, Andrew P. Fellowes, Stephen B. Fox, Owen W.J. Prall

Neoantigen identification strategies enable personalized immunotherapy in refractory solid tumors

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Abstract

BACKGROUND. Recent genomic and bioinformatic technological advances have made it possible to dissect the immune response to personalized neoantigens encoded by tumor-specific mutations. However, timely and efficient identification of neoantigens is still one of the major obstacles to using personalized neoantigen-based cancer immunotherapy. METHODS. Two different pipelines of neoantigens identification were established in this study: (1) Clinical grade targeted sequencing was performed in patients with refractory solid tumor, and mutant peptides with high variant allele frequency and predicted high HLA-binding affinity were de novo synthesized. (2) An inventory-shared neoantigen peptide library of common solid tumors was constructed, and patients' hotspot mutations were matched to the neoantigen peptide library. The candidate neoepitopes were identified by recalling memory T-cell responses in vitro. Subsequently, neoantigen-loaded dendritic cell vaccines and neoantigen-reactive T cells were generated for personalized immunotherapy in six patients. RESULTS. Immunogenic neo-epitopes were recognized by autologous T cells in 3 of 4 patients who utilized the de novo synthesis mode and in 6 of 13 patients who performed shared neoantigen peptide library, respectively. A metastatic thymoma patient achieved a complete and durable response beyond 29 months after treatment. Immune-related partial response was observed in another patient with metastatic pancreatic cancer. The remaining four patients achieved the prolonged stabilization of disease with a median PFS of 8.6 months. CONCLUSIONS. The current study provided feasible pipelines for neoantigen identification. Implementing these strategies to individually tailor neoantigens could facilitate the neoantigen-based translational immunotherapy research. TRIAL REGSITRATION. ChiCTR.org ChiCTR-OIC-16010092, ChiCTR-OIC-17011275, ChiCTR-OIC-17011913; ClinicalTrials.gov NCT03171220. FUNDING. This work was funded by grants from the National Key Research and Development Program of China (Grant No. 2017YFC1308900), the National Major Projects for “Major New Drugs Innovation and Development” (Grant No.2018ZX09301048-003), the National Natural Science Foundation of China (Grant No. 81672367, 81572329, 81572601), and the Key Research and Development Program of Jiangsu Province (No. BE2017607).

Authors

Fangjun Chen, Zhengyun Zou, Juan Du, Shu Su, Jie Shao, Fanyan Meng, Ju Yang, Qiuping Xu, Naiqing Ding, Yang Yang, Qin Liu, Qin Wang, Zhichen Sun, Shujuan Zhou, Shiyao Du, Jia Wei, Baorui Liu

Cleavage factor 25 deregulation contributes to pulmonary fibrosis through alternative polyadenylation

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Abstract

Idiopathic pulmonary fibrosis (IPF) is a chronic and deadly disease with a poor prognosis and few treatment options. Pathological remodeling of the extracellular matrix (ECM) by myofibroblasts is a key factor that drives disease pathogenesis, although the underlying mechanisms remain unknown. Alternative polyadenylation (APA) has recently been shown to play a major role in cellular responses to stress by driving the expression of fibrotic factors and ECMs through altering microRNA sensitivity, but a connection to IPF has not been established. Here, we demonstrate that CFIm25, a global regulator of APA, is down-regulated in the lungs of patients with IPF and mice with pulmonary fibrosis, with its expression selectively reduced in alpha-smooth muscle actin (α-SMA) positive fibroblasts. Following the knockdown of CFIm25 in normal human lung fibroblasts, we identified 808 genes with shortened 3′UTRs, including those involved in the transforming growth factor-β signaling pathway, the Wnt signaling pathway, and cancer pathways. The expression of key pro-fibrotic factors can be suppressed by CFIm25 overexpression in IPF fibroblasts. Finally, we demonstrate that deletion of CFIm25 in fibroblasts or myofibroblast precursors using either the Col1a1 or the Foxd1 promoter enhances pulmonary fibrosis after bleomycin exposure in mice. Taken together, our results identified CFIm25 down-regulation as a novel mechanism to elevate pro-fibrotic gene expression in pulmonary fibrosis.

Authors

Tingting Weng, Junsuk Ko, Chioniso P. Masamha, Zheng Xia, Yu Xiang, Ning-yuan Chen, Jose G. Molina, Scott Collum, Tinne C. Mertens, Fayong Luo, Kemly Philip, Jonathan Davies, Jingjing Huang, Cory Wilson, Rajarajan A. Thandavarayan, Brian A. Bruckner, Soma S.K. Jyothula, Kelly A. Volcik, Lei Li, Leng Han, Wei Li, Shervin Assassi, Harry Karmouty-Quintana, Eric J. Wagner, Michael R. Blackburn

Lkb1 deletion in periosteal mesenchymal progenitors induces osteogenic tumors through mTORC1 activation

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Abstract

Bone osteogenic sarcoma has a poor prognosis as the exact cell of origin and the signaling pathways underling tumor formation remain undefined. Here, we report an osteogenic tumor mouse model based on the conditional knockout of liver kinase b1 (Lkb1; also known as Stk11) in Cathepsin K (Ctsk)-Cre expressing cells. Lineage tracing studies demonstrated that Ctsk-Cre could label a population of periosteal cells. The cells functioned as mesenchymal progenitors with regard to markers and functional properties. LKB1 deficiency increased proliferation and osteoblast differentiation of Ctsk+ periosteal cells, while downregulation of mTORC1 activity, using Raptor genetic mouse model or mTORC1 inhibitor treatment, ameliorated tumor progression of Ctsk-Cre Lkb1fllfl mice. Xenograft mouse models, using human osteosarcoma cell lines, also demonstrated that LKB1 deficiency promoted tumor formation, while mTOR inhibition suppressed xenograft tumor growth. In summary, we identified periosteum-derived Ctsk-Cre expressing cells as a cell of origin for osteogenic tumor and suggested the LKB1-mTORC1 pathway as a promising target for treatment of osteogenic tumor.

Authors

Yujiao Han, Heng Feng, Jun Sun, Xiaoting Liang, Zhuo Wang, Wenhui Xing, Qinggang Dai, Yang Yang, Anjia Han, Zhanying Wei, Qing Bi, Hongbin Ji, Tiebang Kang, Weiguo Zou

Ferroptotic cell death and TLR4/Trif signaling initiate neutrophil recruitment after heart transplantation

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Abstract

Non-apoptotic forms of cell death can trigger sterile inflammation through the release of danger-associated molecular patterns, which are recognized by innate immune receptors. However, despite years of investigation the mechanisms which initiate inflammatory responses after heart transplantation remain elusive. Here, we demonstrate that ferrostatin-1 (Fer-1), a specific inhibitor of ferroptosis, decreases the level of pro-ferroptotic hydroperoxy-arachidonoyl-phosphatidylethanolamine, reduces cardiomyocyte cell death and blocks neutrophil recruitment following heart transplantation. Inhibition of necroptosis had no effect on neutrophil trafficking in cardiac grafts. We extend these observations to a model of coronary artery ligation-induced myocardial ischemia reperfusion injury where inhibition of ferroptosis resulted in reduced infarct size, improved left ventricular systolic function, and reduced left ventricular remodeling. Using intravital imaging of cardiac transplants, we uncover that ferroptosis orchestrates neutrophil recruitment to injured myocardium by promoting adhesion of neutrophils to coronary vascular endothelial cells through a TLR4/TRIF/type I IFN signaling pathway. Thus, we have discovered that inflammatory responses after cardiac transplantation are initiated through ferroptotic cell death and TLR4/Trif-dependent signaling in graft endothelial cells. These findings provide a platform for the development of therapeutic strategies for heart transplant recipients and patients, who are vulnerable to ischemia reperfusion injury following restoration of coronary blood flow.

Authors

Wenjun Li, Guoshuai Feng, Jason M. Gauthier, Inessa Lokshina, Ryuji Higashikubo, Sarah Evans, Xinping Liu, Adil Hassan, Satona Tanaka, Markus Cicka, Hsi-Min Hsiao, Daniel Ruiz-Perez, Andrea Bredemeyer, Richard W. Gross, Douglas L. Mann, Yulia Y. Tyurina, Andrew E. Gelman, Valerian E. Kagan, Andreas Linkermann, Kory J. Lavine, Daniel Kreisel

BETP degradation simultaneously targets acute myelogenous leukemia stem cells and the microenvironment

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Abstract

Anti-leukemic effect of BET/BRD4 (BETP) protein inhibition has been largely attributed to transcriptional downregulation of cellular anabolic/anti-apoptotic processes but its effect on bone marrow microenvironment, a sanctuary favoring persistence of leukemia stem/progenitor cells, is unexplored. Sustained degradation of BETP with small-molecule BET proteolysis-targeting chimera (PROTAC), ARV-825, resulted in marked downregulation of surface CXCR4 and CD44, key proteins in leukemia-microenvironment interaction, in AML cells. Abrogation of surface CXCR4 expression impaired SDF-1α directed migration and was mediated through transcriptional down-regulation of PIM1 kinase that in turn phosphorylates CXCR4 and facilitates its surface localization. Down-regulation of CD44/CD44v8-10 impaired cystine uptake, lowered intracellular reduced glutathione and increased oxidative stress. More importantly, BETP degradation markedly decreased CD34+CD38-CD90-CD45RA+ leukemic stem cell population and alone or in combination with Cytarabine, prolonged survival in mouse model of human leukemia including AML-PDX. Gene expression profiling and single cell proteomics confirmed down regulation of the gene signatures associated with ‘stemness’ in AML and Wnt/β-catenin, Myc pathways. Hence, BETP degradation by ARV-825 simultaneously targets cell intrinsic signaling, stromal interactions and metabolism in AML.

Authors

Sujan Piya, Hong Mu, Seemana Bhattacharya, Philip L. Lorenzi, R. Eric Davis, Teresa McQueen, Vivian Ruvolo, Natalia Baran, Zhiqiang Wang, Yimin Qian, Craig M. Crews, Marina Konopleava, Jo Ishizawa, M. James You, Hagop Kantarjian, Michael Andreeff, Gautam Borthakur

Differential immune profiles distinguish the mutational subtypes of gastrointestinal stromal tumor

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Abstract

Gastrointestinal stromal tumor (GIST) is the most common human sarcoma, frequently characterized by an oncogenic mutation in the KIT or platelet-derived growth factor receptor alpha (PDGFRA) genes. We performed RNA sequencing of 75 human GIST tumors from 75 patients, comprising the largest cohort of GISTs sequenced to date, in order to discover differences in the immune infiltrates of KIT and PDGFRA-mutant GIST. Through bioinformatics, immunohistochemistry, and flow cytometry, we found that PDGFRA-mutant GISTs harbored more immune cells with increased cytolytic activity when compared to KIT-mutant GISTs. PDGFRA-mutant GISTs expressed many chemokines, such as CXCL14, at a significantly higher level when compared to KIT-mutant GISTs and exhibited more diverse driver-derived neoepitope:HLA binding, both of which may contribute to PDGFRA-mutant GIST immunogenicity. Through machine learning, we generated gene expression-based immune profiles capable of differentiating KIT and PDGFRA-mutant GISTs, and also identified additional immune features of high PD-1 and PD-L1 expressing tumors across all GIST mutational subtypes, which may provide insight into immunotherapeutic opportunities and limitations in GIST.

Authors

Gerardo A. Vitiello, Timothy G. Bowler, Mengyuan Liu, Benjamin D. Medina, Jennifer Q. Zhang, Nesteene J. Param, Jennifer K. Loo, Rachel L. Goldfeder, Frederic Chibon, Ferdinand Rossi, Shan Zeng, Ronald P. DeMatteo

Non-immune cell-derived ICOS ligand functions as a renoprotective αvβ3 integrin-selective antagonist

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Abstract

Soluble urokinase receptor (suPAR) is a circulatory molecule that activates αvβ3 integrin on podocytes, causes foot process effacement, and contributes to proteinuric kidney disease. While active integrin can be targeted by antibodies and small molecules, endogenous inhibitors haven’t been discovered yet. Here we report a novel, renoprotective role for inducible costimulator (ICOS) ligand (ICOSL) in early kidney disease through its selective binding to podocyte αvβ3 integrin. Contrary to ICOSL’s immune-regulatory role, ICOSL in non-hematopoietic cells limited the activation of αvβ3 integrin. Specifically, ICOSL contains arginine-glycine-aspartate (RGD) motif, which allowed for a high affinity and selective binding to αvβ3 and modulation of podocyte adhesion. This binding was largely inhibited either by a synthetic RGD peptide or by a disrupted RGD sequence in ICOSL. ICOSL binding favored the active αvβ3 rather than the inactive form and showed little affinity for other integrins. Consistent with the rapid induction of podocyte ICOSL by inflammatory stimuli, glomerular ICOSL expression was increased in biopsies of early stage human proteinuric kidney diseases. Icosl deficiency in mice resulted in an increased susceptibility to proteinuria that was rescued by recombinant ICOSL. Our work identified a novel role for ICOSL, which serves as an endogenous αvβ3-selective antagonist to maintain glomerular filtration.

Authors

Kwi Hye Koh, Yanxia Cao, Steve Mangos, Nicholas J. Tardi, Ranadheer R. Dande, Ha Won Lee, Beata Samelko, Mehmet M. Altintas, Vincent P. Schmitz, Hyun Lee, Kamalika Mukherjee, Vasil Peev, David J. Cimbaluk, Jochen Reiser, Eunsil Hahm