Methyltransferase inhibitors restore SATB1 protective activity against cutaneous T cell lymphoma in mice

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Abstract

Cutaneous T cell lymphoma (CTCL) has a poorly understood etiology and no cure. Using conditional knockout mice, we found that ablation of the genomic organizer Special AT-rich sequence-binding protein-1 (Satb1) caused malignant transformation of mature, skin-homing, Notch-activated CD4+ and CD8+ T-cells into progressively fatal lymphoma. Mechanistically, Satb1 restrained Stat5 phosphorylation and the expression of skin-homing chemokine receptors in mature T-cells. Notably, methyltransferase-dependent epigenetic repression of SATB1 was universally found in human Sézary syndrome, but not in other peripheral T-cell malignancies. H3K27 and H3K9 trimethylation occluded the SATB1 promoter in Sézary cells, while inhibition of SUV39H1/2 methyltransferases (unlike EZH2 inhibition), restored protective SATB1 expression and selectively abrogated the growth of primary Sézary cells more effectively than romidepsin. Therefore, inhibition of methyltransferases that silence SATB1 could address an unmet need for patients with Mycosis fungoides/Sézary syndrome, a set of incurable diseases.

Authors

Carly M. Harro, Jairo Perez-Sanz, Tara Lee Costich, Kyle K. Payne, Carmen M. Anadon Galindo, Ricardo A. Chaurio, Subir Biswas, Gunjan Mandal, Kristen E. Rigolizzo, Kimberly B. Sprenger, Jessica A. Mine, Louise Showe, Xiaoqing Yu, Kebin Liu, Paulo C. Rodriguez, Javier Pinilla-Ibarz, Lubomir Sokol, Jose R. Conejo-Garcia

TREM-1 orchestrates Angiotensin II-induced monocyte trafficking and promotes experimental abdominal aortic aneurysm

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Abstract

The triggering receptor expressed on myeloid cells-1 (TREM-1) drives inflammatory responses in several cardiovascular diseases but its role in abdominal aortic aneurysm (AAA) remains unknown. Our objective was to explore the role of TREM-1 in a mouse model of Angiotensin (Ang) II-induced AAA. TREM-1 expression was detected in mouse aortic aneurysm and colocalizes with macrophages. Trem1 gene deletion (Apoe-/-Trem1-/-), as well as TREM-1 pharmacological blockade with LR-12 peptide limited both AAA development and severity. Trem1 gene deletion attenuated the inflammatory response in the aorta, with a reduction of Il1b, Tnfa, Mmp2 and Mmp9 mRNA expression, and led to a decreased macrophage content, due to a reduction of Ly6Chi classical monocyte trafficking. Conversely, antibody-mediated TREM-1 stimulation exacerbated Ly6Chi monocyte aorta infiltration after AngII infusion through CD62L up-regulation and promoted pro-inflammatory signature in the aorta, resulting in worsening AAA severity. AngII infusion stimulated TREM-1 expression and activation on Ly6Chi monocytes through AngII Receptor Type I (AT1R). In human AAA, TREM-1 was detected and TREM1 mRNA expression correlated with SELL mRNA expression. Finally, circulating levels of sTREM-1 were increased in patients with AAA when compared to patients without AAA. In conclusion, TREM-1 is involved in AAA pathophysiology and may represent a promising therapeutic target in human.

Authors

Marie Vandestienne, Yujiao Zhang, Icia Santos-Zas, Rida Al-Rifai, Jeremie Joffre, Andreas Giraud, Ludivine Laurans, Bruno Esposito, Florence Pinet, Patrick Bruneval, Juliette Raffort, Fabien Lareyre, Jose Vilar, Amir Boufenzer, Lea Guyonnet, Coralie L. Guerin, Eric Clauser, Jean-Sébastien Silvestre, Sylvie Lang, Laurie Soulat-Dufour, Alain Tedgui, Ziad Mallat, Soraya Taleb, Alexandre Boissonnas, Marc Derive, Giulia Chinetti, Hafid Ait-Oufella

The vascular landscape of human cancer

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Abstract

Tumors depend on a blood supply to deliver oxygen and nutrients, making tumor vasculature an attractive anti-cancer target. However, only a fraction of cancer patients benefits from angiogenesis inhibitors. Whether anti-angiogenic therapy would be more effective if targeted to individuals with specific tumor characteristics is unknown. To better characterize the tumor vascular environment both within and between cancer types, we developed a standardized metric – the Endothelial Index (EI) – to estimate vascular density in over 10,000 human tumors, corresponding to 31 solid tumor types, from transcriptome data. We then used this index to compare hyper- and hypo-vascular tumors, enabling the classification of human tumors into six vascular microenvironment signatures (VMSs) based on the expression of a panel of 24 vascular hub genes. EI and VMS correlated with known tumor vascular features and were independently associated with prognosis in certain cancer types. Retrospective testing of clinical trial data identified VMS2 classification as a powerful biomarker for response to bevacizumab. Our studies thus provide an unbiased picture of human tumor vasculature which may enable more precise deployment of anti-angiogenesis therapy.

Authors

Benjamin M. Kahn, Alfredo Lucas, Rohan Alur, Maximilian D. Wengyn, Gregory W. Schwartz, Jinyang Li, Kathryn Sun, H. Carlo Maurer, Kenneth P. Olive, Robert B. Faryabi, Ben Stanger

Correction of vasopressin deficit in the lateral septum ameliorates social deficits of mouse autism model

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Abstract

Intellectual and social disabilities are common comorbidities in adolescents and adults with MAGEL2 gene deficiency characterizing the Prader-Willi and Schaaf-Yang neurodevelopmental syndromes. The cellular and molecular mechanisms underlying the risk for autism in these syndromes are not understood. We ask whether vasopressin functions are altered by MAGEL2 deficiency and whether a treatment with vasopressin can alleviate the disabilities of social behavior. We used Magel2 knockout mice (adult males) combined with optogenetic or pharmacological tools to characterize disease modifications in the vasopressinergic brain system and monitor its impact on neurophysiological and behavioral functions. We find that the activation of vasopressin neurons and its projections in the lateral septum are inappropriate to perform a social habituation/discrimination task. Mechanistically, the lack of vasopressin impedes the deactivation of somatostatin neurons in the lateral septum, which predicts social discrimination deficits. Correction of vasopressin septal content by administration or optogenetic stimulation of projecting axons suppressed the activity of somatostatin neurons and ameliorated social behavior. This preclinical study identifies vasopressin in the lateral septum as a key factor in the pathophysiology.

Authors

Amélie M. Borie, Yann Dromard, Gilles Guillon, Aleksandra Olma, Maurice Manning, Françoise Muscatelli, Michel G. Desarmenien, Freddy Jeanneteau

Myeloid cell-targeted STAT3 inhibition sensitizes head and neck cancers to radiotherapy and T cell-mediated immunity

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Abstract

The tumor microenvironment affects the outcome of radiotherapy against head and neck squamous cell carcinoma (HNSCC). We recently found that tolerogenic myeloid cells accumulate in circulation of HNSCC patients undergoing radiotherapy. Here, we analyzed tumor-containing lymph nodes biopsies collected from these patients. After two-weeks of radiotherapy, we found an increase in tumor-associated macrophages (TAMs) with activated STAT3, while CD8 T-cells were reduced as detected using multiplex IHC. Gene expression profiling indicated upregulation of M2 macrophage-related genes (CD163, CD206), immunosuppressive mediators (ARG1, LIF, TGFB1) and Th2 cytokines (IL4, IL5) in irradiated tumors. We next validated STAT3 as a potential target in human HNSCC-associated TAMs, using UM-SCC1 xenotransplants in humanized mice. Local injections of myeloid cell-targeted STAT3 antisense oligonucleotide (CpG-STAT3ASO) activated human DCs/macrophages, promoted CD8 T-cell recruitment and thereby arrested UM-SCC1 tumor growth. Furthermore, CpG-STAT3ASO synergized with tumor irradiation against syngeneic HPV+ mEERL and HPV– MOC2 HNSCC tumors in mice, triggering tumor regression and/or extending animal survival. The antitumor immune responses were CD8+ and CD4+ T-cell-dependent and associated with the activation of antigen-presenting cells (DCs/M1 macrophages) and increased CD8+ to regulatory T-cell ratio. Our observations suggest that targeted inhibition of STAT3 in tumor-associated myeloid cells augments the efficacy of radiotherapy against HNSCC.

Authors

Dayson Moreira, Sagus Sampath, Haejung Won, Seok Voon White, Yu-Lin Su, Marice Alcantara, Chongkai Wang, Peter P. Lee, Ellie Maghami, Erminia Massarelli, Marcin Kortylewski

The loss-of-function PCSK9^Q152H variant increases ER chaperones GRP78 and GRP94 and protects against liver injury

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Abstract

ABSTRACTIndividuals harboring the loss-of-function (LOF) proprotein convertase subtilising/kexin type 9 Gln152His variation (PCSK9Q152H) have low circulating low-density lipoprotein (LDL) cholesterol levels and are therefore protected against cardiovascular disease (CVD). This uncleavable form of pro-PCSK9, however, is retained in the endoplasmic reticulum (ER) of liver hepatocytes where it would be expected to contribute to ER storage disease (ERSD); a heritable condition known to cause systemic ER stress and liver injury. Here, we examined liver function in members of several French-Canadian families known to carry the PCSK9Q152H variation. We report that PCSK9Q152H carriers exhibited marked hypocholesterolemia and normal liver function despite their lifelong state of ER PCSK9 retention. Mechanistically, hepatic overexpression of PCSK9Q152H using adeno-associated viruses in male mice greatly increased the stability of key ER stress response chaperones in liver hepatocytes and unexpectedly protected against ER stress and liver injury rather than to induce them. Our findings show that ER retention of PCSK9 not only reduced CVD risk in patients but may also protect against ERSD and other ER stress-driven conditions of the liver. In summary, we have uncovered a co-chaperone function for PCSK9Q152H that explains its hepatoprotective effects and generated a translational mouse model for further mechanistic insights into this clinically relevant LOF PCSK9 variant.

Authors

Paul F. Lebeau, Hanny Wassef, Jae Hyun Byun, Khrystyna Platko, Brandon Ason, Simon Jackson, Joshua Dobroff, Susan Shetterly, William G. Richards, Ali A. Al-Hashimi, Kevin D. Won, Majambu Mbikay, Annik Prat, An Tang, Guillaume Paré, Renata Pasqualini, Nabil G. Seidah, Wadih Arap, Michel Chretien, Richard C. Austin

Extracellular traps released by antimicrobial TH17 cells contribute to host defense

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Abstract

TH17 cell subpopulations have been defined that contribute to inflammation and homeostasis, yet the characteristics of TH17 cells that contribute to host defense against infection are not clear. To elucidate the antimicrobial machinery of the TH17 subset, we studied the response to Cutibacterium acnes, a skin commensal that is resistant to IL-26, the only known TH17 secreted protein with direct antimicrobial activity. We generated C. acnes-specific antimicrobial TH17 clones (AMTH17) with varying antimicrobial activity against C. acnes, which we correlated by RNA-seq to the expression of transcripts encoding proteins that contribute to antimicrobial activity. Additionally, we validated that AMTH17-mediated killing of C. acnes as well as bacterial pathogens, was dependent on the secretion of granulysin, granzyme B, perforin and histone H2B. We found that AMTH17s can release fibrous structures composed of DNA decorated with the histone H2B that entangle C. acnes that we call T cell extracellular traps (TETs). Within acne lesions, H2B and IL-17 colocalized in CD4+ T cells, in proximity to TETs in the extracellular space composed of DNA decorated with H2B. This study identifies a functionally distinct subpopulation of TH17 cells with an ability to form TETs containing secreted antimicrobial proteins that capture and kill bacteria.

Authors

George W. Agak, Alice Mouton, Rosane Teles, Thomas A. Weston, Marco Morselli, Priscila R. Andrade, Matteo Pellegrini, Robert L. Modlin

Bone marrow adipogenic lineage precursors (MALPs) promote osteoclastogenesis in bone remodeling and pathologic bone loss

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Abstract

Bone is maintained by coupled activities of bone-forming osteoblasts/osteocytes and bone-resorbing osteoclasts. Alterations in this relationship can lead to pathologic bone loss, such as osteoporosis. It is well known that osteogenic cells support osteoclastogenesis via production of RANKL. Interestingly, our recently identified bone marrow mesenchymal cell population—marrow adipogenic lineage precursors (MALPs) that form a multi-dimensional cell network in bone—was computationally demonstrated to be the most interactive with monocyte-macrophage lineage cells through high and specific expression of several osteoclast regulatory factors, including RANKL. Using an adipocyte-specific Adipoq-Cre to label MALPs, we demonstrated that mice with RANKL deficiency in MALPs have a drastic increase in trabecular bone mass in long bones and vertebrae starting from 1 month of age, while their cortical bone appears normal. This phenotype was accompanied by diminished osteoclast number and attenuated bone formation at the trabecular bone surface. Reduced RANKL signaling in calvarial MALPs abolished osteolytic lesions after lipopolysaccharide (LPS) injections. Furthermore, in ovariectomized mice, elevated bone resorption was partially attenuated by RANKL deficiency in MALPs. In summary, our studies identified MALPs as a critical player in controlling bone remodeling during normal bone metabolism and pathological bone loss in a RANKL-dependent fashion.

Authors

Wei Yu, Leilei Zhong, Lutian Yao, Yulong Wei, Tao Gui, Ziqing Li, Hyunsoo Kim, Nicholas Holdreith, Xi Jiang, Wei Tong, Nathaniel A. Dyment, Xiaowei Sherry Liu, Shuying Yang, Yongwon Choi, Jaimo Ahn, Ling Qin

TLR3 controls constitutive IFN-b antiviral immunity in human fibroblasts and cortical neurons

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Abstract

Human herpes simplex virus-1 (HSV-1) encephalitis can be caused by inborn errors of the TLR3 pathway resulting in impairment of central nervous system (CNS) cell-intrinsic antiviral immunity. Deficiencies of the TLR3 pathway impair cell-intrinsic immunity to vesicular stomatitis virus (VSV) and HSV-1 in fibroblasts, and to HSV-1 in cortical but not trigeminal neurons. The underlying molecular mechanism is thought to involve impaired IFN-a/b induction by the TLR3 recognition of dsRNA viral intermediates or by-products. However, we show here that human TLR3 controls constitutive levels of IFNB mRNA and secreted bioactive IFN-b protein, thereby also constitutive mRNA levels for IFN-stimulated genes (ISGs) in fibroblasts. Tlr3-/- mouse embryonic fibroblasts also have lower basal ISG levels. Moreover, human TLR3 controls basal levels of IFN-b secretion and ISGs mRNA in induced pluripotent stem cell-derived cortical neurons. Consistently, TLR3-deficient human fibroblasts and cortical neurons are vulnerable not only to both VSV and HSV-1, but also to several other families of viruses. The mechanism by which TLR3 restricts viral growth in human fibroblasts and cortical neurons in vitro, and by which the human central nervous system prevents infection by HSV-1 in vivo, is therefore based on the control of early viral infection by basal IFN-b immunity, rather than viral recognition triggering an amplification of IFN-a/b production.

Authors

Daxing Gao, Michael J. Ciancanelli, Peng Zhang, Oliver Harschnitz, Vincent Bondet, Mary Hasek, Jie Chen, Xin Mu, Yuval Itan, Aurélie Cobat, Vanessa Sancho-Shimizu, Benedetta Bigio, Lazaro Lorenzo, Gabriele Ciceri, Jessica L. McAlpine, Esperanza Anguiano, Emmanuelle Jouanguy, Damien Chaussabel, isabelle Meyts, Michael S. Diamond, Laurent Abel, Sun Hur, Gregory A. Smith, Luigi D. Notarangelo, Darragh Duffy, Lorenz Studer, Jean-Laurent Casanova, Shen-Ying Zhang

Congenital heart disease risk loci identified by genome-wide association study in European patients

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Abstract

Genetic factors undoubtedly affect the development of congenital heart disease (CHD), but still remain ill-defined. We sought to identify genetic risk factors associated with CHD and to accomplish functional analysis of single nucleotide polymorphisms (SNP)-carrying genes. We performed a genome-wide association study of 4,034 Caucasian CHD patients and 8,486 healthy controls. One SNP on chromosome 5q22.2 reached genome-wide significance across all CHD phenotypes and was also indicative for septal defects. One region on chromosome 20p12.1 pointing to the MACROD2 locus identified four highly significant SNPs in patients with transposition of the great arteries (TGA). Three highly significant risk variants on chromosome 17q21.32 within the GOSR2 locus were detected in patients with anomalies of thoracic arteries and veins (ATAV). Genetic variants associated with ATAV are suggested to influence expression of WNT3, and variant rs870142 related to septal defects is proposed to influence expression of MSX1. The expression of all four genes was analyzed during cardiac differentiation of human and murine induced pluripotent stem cells in vitro and by single-cell RNAseq analyses of developing murine and human hearts. Our data show that MACROD2, GOSR2, WNT3 and MSX1 play an essential functional role in heart development at the embryonic and newborn stage.

Authors

Harald Lahm, Meiwen Jia, Martina Dreßen, Felix F. M. Wirth, Nazan Puluca, Ralf Gilsbach, Bernard Keavney, Julie Cleuziou, Nicole Beck, Olga Bondareva, Elda Dzilic, Melchior Burri, Karl C. König, Johannes A. Ziegelmüller, Claudia Abou-Ajram, Irina Neb, Zhong Zhang, Stefanie A. Doppler, Elisa Mastantuono, Peter Lichtner, Gertrud Eckstein, Jürgen Hörer, Peter Ewert, James R. Priest, Lutz Hein, Rüdiger Lange, Thomas Meitinger, Heather J. Cordell, Bertram Müller-Myhsok, Markus Krane