Prognostic and predictive value of an immune infiltration signature in diffuse lower-grade gliomas

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Abstract

BACKGROUND. Lower-grade gliomas (LGGs) vary widely in terms of the patient’s overall survival (OS). There is a lack of valid method that could exactly predict the survival. The effects of intratumoral immune infiltration on clinical outcome have been widely reported. Thus, we aim to develop an immune infiltration signature to predict the survival of LGG patients. METHODS. We analyzed 1216 LGGs from 5 public datasets, including 2 RNA-Seq datasets and 3 microarray datasets. Least absolute shrinkage and selection operator (LASSO) Cox regression was used to select an immune infiltration signature and build a risk score. The performance of the risk score was assessed in the training set (329 patients), internal validation set (140 patients), and 4 external validation sets (405, 118, 88, and 136 patients). RESULTS. An immune infiltration signature consisting of 20 immune metagenes was used to generate a risk score. The performance of the risk score was thoroughly verified in the training and validation sets. Additionally, we found that the risk score was positively correlated with the expression levels of TGFβ and PD-L1, which were important targets of combination immunotherapy. Furthermore, a nomogram incorporating the risk score, patient’s age, and tumor grade was developed to predict the OS, and it performed well in all the training and validation sets (C-index: 0.873, 0.881, 0.781, 0.765, 0.721, and 0.753, respectively). CONCLUSIONS. The risk score based on the immune infiltration signature has reliable prognostic and predictive value for patients with LGGs and might be a potential biomarker for the co-targeting immunotherapy. FUNDING. The National Natural Science Foundation of China (Grant No. 81472370 and 81672506), the Natural Science Foundation of Beijing (Grant No. J180005), the National High Technology Research and Development Program of China (863 Program, Grant No. 2014AA020610) and the National Basic Research Program of China (973 Program, Grant No. 2014CB542006).

Authors

Lai-Rong Song, Jian-Cong Weng, Cheng-Bei Li, Xu-Lei Huo, Huan Li, Shu-Yu Hao, Zhen Wu, Liang Wang, Da Li, Jun-Ting Zhang

Control of PTH secretion by the TRPC1 ion channel

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Abstract

Familial Hypocalciuric Hypercalcemia (FHH) is a genetic condition associated with hypocalciuria, hypercalcemia and in some cases inappropriately high levels of circulating parathyroid hormone (PTH). FHH is associated with inactivating mutations in CaSR encoding the Ca2+ sensing receptor (CaSR), a G protein coupled receptor (GPCR) and GNA11 encoding G protein subunit alpha 11 (Gα11), implicating defective GPCR signaling as the root pathophysiology for FHH. However, the downstream mechanism by which CaSR activation inhibits PTH production/secretion is incompletely understood. Here, we show that mice lacking the transient receptor potential canonical channel 1 (TRPC1) develop chronic hypercalcemia, hypocalciuria, and elevated PTH levels mimicking human FHH. Ex vivo and in vitro studies reveal that TRPC1 serves a necessary and sufficient mediator to suppress PTH secretion from parathyroid glands (PTG) downstream of CaSR in response to high extracellular Ca2+ concentration. Gα11 physically interacts with both the N- and C-termini of TRPC1 and enhances CaSR-induced TRPC1 activity in transfected cells. These data identify TRPC1-mediated Ca2+ signaling as an essential component of the cellular apparatus controlling PTH secretion in the PTG downstream of CaSR.

Authors

Marta Onopiuk, Bonnie Eby, Vasyl Nesin, Peter Ngo, Megan Lerner, Caroline M. Gorvin, Victoria J. Stokes, Rajesh V. Thakker, Maria Luisa Brandi, Wenhan Chang, Mary Beth Humphrey, Leonidas Tsiokas, Kai Lau

Ribonuclease 1 attenuates septic cardiomyopathy and cardiac apoptosis in a murine model of polymicrobial sepsis

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Abstract

Septic cardiomyopathy is a life-threatening organ dysfunction caused by sepsis. Ribonuclease 1 (RNase 1) belongs to a group of host-defense peptides that specifically cleave extracellular RNA (eRNA). The activity of RNase1 is inhibited by ribonuclease-inhibitor 1 (RNH1). The role of RNase 1 in septic cardiomyopathy and associated cardiac apoptosis, however, is completely unknown. Here, we showed that sepsis resulted in a significant increase in RNH1 and eRNA serum levels compared to those of healthy subjects (p < 0.05). Treatment with RNase 1 resulted in a significant decrease of apoptosis, induced by the intrinsic pathway, and TNF expression in murine cardiomyocytes exposed to either necrotic cardiomyocytes or serum of septic patients for 16 h (p < 0.05). Furthermore, treatment of septic mice with RNase 1 resulted in a reduction in cardiac apoptosis, TNF expression and septic cardiomyopathy (p < 0.05). These data demonstrate that eRNA plays a crucial role in the pathophysiology of the organ (cardiac) dysfunction in sepsis and RNase and RNH1 may be new therapeutic targets/strategies to reduce the cardiac injury and dysfunction caused by sepsis.

Authors

Elisabeth Zechendorf, Caroline E O'Riordan, Lara Stiehler, Natalie Wischmeyer, Fausto Chiazza, Debora Collotta, Bernd Denecke, Sabrina Ernst, Gerhard Müller-Newen, Sina M. Coldewey, Bianka Wissuwa, Massimo Collino, Tim-Philipp Simon, Tobias Schuerholz, Christian Stoppe, Gernot Marx, Christoph Thiemermann, Lukas Martin

Irreversible JNK1-JUN inhibition by JNK-IN-8 sensitizes pancreatic cancer to 5-FU/FOLFOX chemotherapy

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Abstract

Over 55,000 people in the US are diagnosed with pancreatic ductal adenocarcinoma (PDAC) yearly, and fewer than 20% of these patients survive a year beyond diagnosis. Chemotherapies are considered or used in nearly every PDAC case, but there is limited understanding of the complex signaling responses underlying resistance to these common treatments. Here, we take an unbiased approach to study protein kinase network changes following chemotherapies in patient-derived xenograft (PDX) models of PDAC to facilitate design of rational drug combinations. Proteomics profiling following chemotherapy regimens reveals that activation of JNK-JUN signaling occurs after 5-fluorouracil plus leucovorin (5-FU) and FOLFOX (5-FU plus oxaliplatin (OX)), but not after OX alone or gemcitabine. Cell and tumor growth assays with the irreversible inhibitor JNK-IN-8 and genetic manipulations demonstrate that JNK and JUN each contribute to chemoresistance and cancer cell survival after FOLFOX. Active JNK1 and JUN are specifically implicated in these effects, and synergy with JNK-IN-8 is linked to FOLFOX-mediated JUN activation, cell cycle dysregulation, and DNA damage response. This study highlights the potential for JNK-IN-8 as a biological tool and potential combination therapy with FOLFOX in PDAC and reinforces the need to tailor treatment to functional characteristics of individual tumors.

Authors

Matthew B. Lipner, Xianlu L. Peng, Chong Jin, Yi Xu, Yanzhe Gao, Michael P. East, Naim U. Rashid, Richard A. Moffitt, Silvia G. Herrera Loeza, Ashley B. Morrison, Brian T. Golitz, Cyrus Vaziri, Lee M. Graves, Gary L. Johnson, Jen Jen Yeh

Aberrant cell migration contributes to defective airway epithelial repair in childhood wheeze

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Abstract

Abnormal wound repair has been observed in the airway epithelium of patients with chronic respiratory diseases including asthma. Therapies focusing on repairing vulnerable airways, particularly in early life, present an extremely novel treatment strategy. We report defective lower airway epithelial cell repair to strongly associate with common pre-school and school-aged wheezing phenotypes, characterised by aberrant migration patterns and reduced α5β1 integrin expression. Next generation sequencing identified the PI3K/Akt pathway as the top upstream transcriptional regulator of α5β1 integrin, where Akt activation enhanced repair and α5β1 integrin expression in primary cultures from children with wheeze. Conversely, inhibition of PI3K/Akt signaling in primary cultures from children without wheeze reduced α5β1 expression and attenuated repair. Importantly, the FDA-approved drug celecoxib, and its non-COX2-inhibiting analogue dimethyl-celecoxib, stimulated the PI3K/Akt-integrin α5β1 axis and restored airway epithelial repair in cells from children with wheeze. When compared with published clinical datasets the identified transcriptomic signature was also associated with viral-induced wheeze exacerbations highlighting the clinical potential of such therapy. Collectively, these results identify airway epithelial restitution via targeting the PI3K/Akt-integrin axis as a novel therapeutic avenue for childhood wheeze and asthma. We propose that the next step in the therapeutic development process should be a proof-of-concept clinical trial since relevant animal models to test the crucial underlying premise are unavailable.

Authors

Thomas Iosifidis, Erika N. Sutanto, Alysia Buckley, Laura A. Coleman, Erin E. Gill, Amy H. Lee, Kak-Ming Ling, Jessica Hillas, Kevin Looi, Luke W. Garratt, Kelly M. Martinovich, Nicole C. Shaw, Samuel T. Montgomery, Elizabeth Kicic-Starcevich, Yuliya V. Karpievitch, Peter Le Souef, Ingrid A. Laing, Shyan Vijayasekaran, Francis J. Lannigan, Paul J. Rigby, Robert E.W. Hancock, Darryl Knight, Stephen M. Stick, Anthony Kicic, on behalf of WAERP, on behalf of AusREC

Angiogenesis stimulated by elevated PDGF-BB in subchondral bone contributes to osteoarthritis development

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Abstract

Increased subchondral bone angiogenesis with blood vessels breaching the tidemark into the avascular cartilage is a diagnostic feature of human osteoarthritis. However, the mechanisms that initiate subchondral bone angiogenesis remain unclear. We show that abnormally increased platelet-derived growth factor-BB (PDGF-BB) secretion by mononuclear preosteoclasts induces subchondral bone angiogenesis, contributing to osteoarthritis development. In mice after destabilization of the medial meniscus (DMM), aberrant joint subchondral bone angiogenesis developed during an early stage of osteoarthritis, before articular cartilage damage occurred. Mononuclear preosteoclasts in subchondral bone secrete excessive amounts of PDGF-BB, which activates platelet-derived growth factor receptor β (PDGFRβ) signaling in pericytes for neo-vessel formation. Selective knockout of PDGF-BB in preosteoclasts attenuates subchondral bone angiogenesis and abrogates joint degeneration and subchondral innervation induced by DMM. Transgenic mice that express PDGF-BB in preosteoclasts recapitulate pathological subchondral bone angiogenesis and develop joint degeneration and subchondral innervation spontaneously. Our study provides the first evidence that PDGF-BB derived from preosteoclasts is a key driver of pathological subchondral bone angiogenesis during osteoarthritis development and offers a new avenue for developing early treatments for this disease.

Authors

Weiping Su, Guanqiao Liu, Xiaonan Liu, Yangying Zhou, Qi Sun, Gehua Zhen, Xiao Wang, Yihe Hu, Peisong Gao, Shadpour Demehri, Xu Cao, Mei Wan

Cardiovascular response to small molecule APJ activation

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Abstract

Heart failure (HF) remains a grievous illness with poor prognosis even with optimal care. The apelin receptor (APJ) counteracts the pressor effect of angiotensin II, attenuates ischemic injury and has the potential to be a novel target to treat HF. Intravenous administration of apelin improves cardiac function acutely in HF patients. However, its short half-life restricts its use to infusion therapy. To identify a longer acting APJ agonist, we conducted a medicinal chemistry campaign leading to the discovery of potent small-molecule APJ agonists with comparable activity to apelin by mimicking the C-terminal portion of apelin-13. Acute infusion increased systolic function and reduced systemic vascular resistance in two rat models of impaired cardiac function. Similar results were obtained in an anesthetized but not a conscious canine HF model. Chronic oral dosing in a rat myocardial infarction model reduced myocardial collagen content and improved diastolic function to a similar extent as losartan, a RAS antagonist standard of care therapy, but lacked additivity with co-administration. Collectively, this work demonstrates the feasibility of developing clinical viable potent small molecule agonists that mimic the endogenous APJ ligand with more favorable drug-like properties and highlight potential limitations for APJ agonism for this indication.

Authors

Brandon Ason, Yinhong Chen, Qi Guo, Kimberly M Hoagland, Ray W. Chui, Mark Fielden, Weston Sutherland, Rhonda Chen, Ying Zhang, Shirley Mihardja, Xiaochuan Ma, Xun Li, Yaping Sun, Dongming Liu, Khanh Nguyen, Jinghong Wang, Ning Li, Sridharan Rajamani, Yusheng Qu, BaoXi Gao, Andrea Boden, Vishnu Chintalgattu, Jim R. Turk, Joyce C. Y. Chan, Liaoyuan A. Hu, Paul Dransfield, Jonathan B. Houze, Jing Man Wong, Ji Ma, Vatee Pattaropong, Murielle M. Veniant, Hugo M Vargas, Gayathri Swaminath, Aarif Khakoo

Neutrophil Extracellular Traps (NETs) promote macrophage inflammation and impair atherosclerosis resolution in mice with diabetes

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Abstract

Neutrophil extracellular traps (NETs) promote inflammation and atherosclerosis progression. NETs are increased in diabetes and impair the resolution of inflammation during wound healing. Atherosclerosis resolution, a process resembling wound healing, is also impaired in diabetes. Thus, we hypothesized that NETs impede atherosclerosis resolution in diabetes by increasing plaque inflammation. Indeed, transcriptomic profiling of plaque macrophages from NET positive and negative areas in low-density lipoprotein receptor-deficient (Ldlr-/-) mice revealed inflammasome and glycolysis pathway upregulation, indicating a heightened inflammatory phenotype. We found that NETs decline during atherosclerosis resolution, which was induced by reducing hyperlipidemia in non-diabetic mice, but they persist in diabetes, exacerbating macrophage inflammation and impairing resolution. In diabetic mice deoxyribonuclease 1 (DNase1) treatment reduced plaque NETs content and macrophage inflammation, promoting atherosclerosis resolution after lipid-lowering. Given that humans with diabetes also exhibit impaired atherosclerosis resolution with lipid-lowering, these data suggest that NETs contribute to the increased cardiovascular disease risk in this population and are a potential therapeutic target.

Authors

Tatjana Josefs, Tessa J. Barrett, Emily J. Brown, Alexandra Quezada, Xiaoyun Wu, Maud Voisin, Jaume Amengual, Edward A. Fisher

Biological sex influences susceptibility to Acinetobacter baumannii pneumonia in mice

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Abstract

Acinetobacter baumannii is an extremely versatile multidrug resistant pathogen with a very high mortality rate therefore, it has become crucial to understand the host response during its infection. Given the importance of mice for modelling infection and their role in pre-clinical drug development equal emphasis should be placed on the utilization of both sexes. Through our studies using a murine model of acute pneumonia with A. baumannii, we observed that female mice were more susceptible to infection. Likewise, treatment of male mice with estradiol increased their susceptibility to infection. Analysis of the airway compartment revealed enhanced inflammation and reduced neutrophil and alveolar macrophage numbers compared to male mice. Depletion of either neutrophils or alveolar macrophages was important for bacterial clearance however, depletion of alveolar macrophages further exacerbated female susceptibility due to severe alterations in metabolic homoeostasis. Our data highlights the importance of utilizing both sexes when assessing host immune pathways.

Authors

Silvia Pires, Adeline C. Peignier, Jeremy Seto, Davida S. Smyth, Dane Parker

The C5a/C5aR2 axis promotes renal inflammation and tissue damage

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Abstract

C5a is a potent inflammatory mediator, which binds C5aR1 and C5aR2. Although pathogenic roles of C5a/C5aR1 axis in inflammatory disorders are well-documented, the roles for C5a/C5aR2 axis in inflammatory disorders and underlying mechanisms remain unclear. Here, we show that C5a/C5aR2 axis contributes to renal inflammation and tissue damage in a mouse model of acute pyelonephritis. Compared with WT littermates, C5ar2-/- mice had significantly reduced renal inflammation, tubular damage and renal bacterial load following bladder inoculation with uropathogenic E coli. The decrease in inflammatory responses in the kidney of C5ar2-/- mice was correlated with reduced intrarenal levels of high mobility group box 1 protein (HMGB1), NLRP3 inflammasome components, cleaved caspase-1 and IL-1β. In vitro, C5a stimulation of macrophages from C5ar1-/- mice (lacking C5aR1 but expressing C5aR2) led to significant upregulation of HMGB1 release, NLRP3/caspase-1 inflammasome activation and IL-1β secretion. Furthermore, blockade of HMGB1 significantly reduced C5a-mediated upregulation of NLRP3/caspase-1 inflammasome activation and IL-1β secretion in the macrophages, implying a HMGB1-dependent upregulation of NLRP3/caspase-1 inflammasome activation in macrophages. Our findings demonstrate a pathogenic role for C5a/C5aR2 axis in renal injury following renal infection and suggest that C5a/C5aR2 axis contributes to renal inflammation and tissue damage through up-regulation of HMGB1 and NLRP3/caspase-1 inflammasome.

Authors

Ting Zhang, Kun-yi Wu, Ning Ma, Lin-ling Wei, Malgorzata A. Garstka, Wuding Zhou, Ke Li