Osteopontin mediates glioblastoma-associated macrophage infiltration and is a therapeutic target

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Abstract

Glioblastoma is highly enriched with macrophages, and osteopontin (OPN) expression levels correlate with glioma grade and the degree of macrophage infiltration, thus we studied whether OPN plays a crucial role in immune modulation. Quantitative PCR, immune blotting, and ELISA were used to determine OPN expression. Knockdown of OPN was achieved using complementary siRNA, shRNA and CRISPR/CAS9 techniques followed by a series of in vitro functional migration and immunological assays. OPN gene-deficient mice were used to examine the roles of non-tumor-derived OPN on survival of mice harboring intracranial gliomas. Patients with mesenchymal GBM show high OPN expression, a negative survival prognosticator. OPN is a potent chemokine for macrophages, and its blockade significantly impaired the ability of glioma cells to recruit macrophages. Integrin αVβ5 (ITGαVβ5) is highly expressed on glioblastoma-infiltrating macrophages and constitutes a major OPN receptor. OPN maintains the M2 macrophage gene signature and phenotype. Both tumor-derived OPN and host-derived OPN was critical for glioma development. OPN deficiency in either the innate immune or glioma cells demonstrated a marked reduction of M2 macrophages and elevated T cell effector activity infiltrating the glioma. Furthermore, OPN deficiency in the glioma cells sensitized them to direct CD8+ T cell cytotoxicity. OPN can be exploited as an immune modulatory target, with efficacious therapeutic results using systemically administered OPN-4-1BB bispecific aptamers, increasing median survival time by 68% (P < 0.05). OPN is an important chemokine for recruiting macrophages to glioblastoma, mediates crosstalk between tumor cells and the innate immune system, and can be exploited as a therapeutic target.

Authors

Jun Wei, Anantha Marisetty, Brett Schrand, Konrad Gabrusiewicz, Yuuri Hashimoto, Martina Ott, Zacharia Grami, Ling-Yuan Kong, Xiaoyang Ling, Hillary G. Caruso, Shouhao Zhou, Y. Alan Wang, Gregory N. Fuller, Jason T. Huse, Eli Gilboa, Nannan Kang, Xingxu Huang, Roel Verhaak, Shulin Li, Amy B. Heimberger

Bone marrow transplantation generates T cell–dependent control of myeloma in mice

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Abstract

Transplantation with autologous hematopoietic progenitors remains an important consolidation treatment for multiple myeloma (MM) patients and is thought to prolong disease plateau-phase by providing intensive cytoreduction. However, transplantation induces inflammation in the context of profound lymphodepletion that may cause hitherto unexpected immunological effects. We developed preclinical models of bone marrow transplantation (BMT) for MM using Vk*MYC myeloma-bearing recipients and donors that were myeloma-naïve or were myeloma-experienced to simulate autologous transplantation. Surprisingly, we demonstrate broad induction of T cell-dependent myeloma control, most efficiently from memory T cells within myeloma-experienced grafts, but also through priming of naïve T cells after BMT. CD8+ T cells from mice with controlled myeloma had a distinct TCR repertoire and higher clonotype overlap relative to myeloma-free BMT recipients. Furthermore, T cell-dependent myeloma control could be adoptively transferred to secondary recipients, and was myeloma clone-specific. Interestingly, donor-derived IL-17A acted directly on myeloma cells expressing the IL-17-receptor to induce a transcriptional landscape that promoted tumor growth and immune escape. Conversely, donor IFNγ secretion and signaling was critical to protective immunity, and was profoundly augmented by CD137 agonists. These data provide new insights into the mechanisms of action of transplantation in myeloma and suggests rational approaches to improving clinical outcome.

Authors

Slavica Vuckovic, Simone A. Minnie, David Smith, Kate H. Gartlan, Thomas S. Watkins, Kate A. Markey, Pamela Mukhopadhyay, Camille Guillerey, Rachel D. Kuns, Kelly R. Locke, Antonia L. Pritchard, Peter A. Johansson, Antiopi Varelias, Ping Zhang, Nicholas D. Huntington, Nicola Waddell, Marta Chesi, John J. Miles, Mark J. Smyth, Geoffrey R. Hill

Temporal dynamics of Wnt-dependent transcriptome reveals an oncogenic Wnt/MYC/ribosome axis

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Abstract

Activating mutations in the Wnt pathway drive a variety of cancers, but the specific targets and pathways activated by Wnt ligands are not fully understood. To bridge this knowledge gap, we performed a comprehensive time-course analysis of Wnt-dependent signaling pathways in an orthotopic model of Wnt-addicted pancreatic cancer, using a PORCN inhibitor currently in clinical trials, and validated key results in additional Wnt-addicted models. The temporal analysis of the drug-perturbed transcriptome demonstrated direct and indirect regulation of greater than 3,500 Wnt activated genes (23% of the transcriptome). Regulation was both via Wnt/β-catenin, and through the modulation of protein abundance of important transcription factors including MYC via Wnt/STOP. Our study identifies a central role of Wnt /β-catenin and Wnt/STOP signaling in controlling ribosomal biogenesis, a key driver of cancer proliferation.

Authors

Babita Madan, Nathan Harmston, Gahyathiri Nallan, Alex Montoya, Peter Faull, Enrico Petretto, David M. Virshup

Gα₁₂ ablation exacerbates liver steatosis and obesity by suppressing USP22/SIRT1-regulated mitochondrial respiration

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Abstract

Non-alcoholic fatty liver disease (NAFLD) arises from mitochondrial dysfunction under sustained imbalance between energy intake and expenditure, but the underlying mechanisms controlling mitochondrial respiration have not been entirely understood. Heterotrimeric G proteins converge signals from activated GPCRs, and modulate cell signaling pathways to maintain metabolic homeostasis. Here, we investigated the regulatory role of Gα12 on hepatic lipid metabolism and whole-body energy expenditure in mice. Fasting increased Gα12 level in mouse liver. Gα12 ablation markedly augmented fasting-induced hepatic fat accumulation. cDNA microarray analysis from Gna12 KO liver revealed that Gα12 signaling pathway regulated sirtuin 1 (SIRT1) and PPARα responsible for mitochondrial respiration. Defective induction of SIRT1 upon fasting was observed in the liver of Gna12 KO mice, which was reversed by lentivirus-mediated Gα12 overexpression in hepatocytes. Mechanistically, Gα12 stabilized SIRT1 protein through transcriptional induction of USP22 via HIF-1α increase. Gα12 levels were markedly diminished in liver biopsies from NAFLD patients. Consistently, Gna12 KO mice fed high-fat diet displayed greater susceptibility to diet-induced liver steatosis and obesity due to decrease in energy expenditure. Our results demonstrate that Gα12 regulates SIRT1-dependent mitochondrial respiration through HIF-1α-dependent USP22 induction, identifying Gα12 as an upstream molecule that contributes to the regulation of mitochondrial energy expenditure.

Authors

Tae Hyun Kim, Yoon Mee Yang, Chang Yeob Han, Ja Hyun Koo, Hyunhee Oh, Su Sung Kim, Byoung Hoon You, Young Hee Choi, Tae-Sik Park, Chang Ho Lee, Hitoshi Kurose, Mazen Noureddin, Ekihiro Seki, Yu-Jui Yvonne Wan, Cheol Soo Choi, Sang Geon Kim

Notch signaling suppresses glucose metabolism in mesenchymal progenitors to restrict osteoblast differentiation

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Abstract

Notch signaling critically controls cell fate decisions in mammals, both during embryogenesis and in adults. In the skeleton, Notch suppresses osteoblast differentiation and sustains bone marrow mesenchymal progenitors during postnatal life. Stabilizing mutations of Notch2 cause the Hajdu-Cheney syndrome characterized by early onset osteoporosis in humans, but the mechanism whereby Notch inhibits bone accretion is not fully understood. Here we report that activation of Notch signaling by either Jagged1 or Notch2 intracellular domain suppresses glucose metabolism and osteoblast differentiation in primary cultures of bone marrow mesenchymal progenitors. Importantly, deletion of Notch2 in the limb mesenchyme increases both glycolysis and bone formation in the long bones of postnatal mice, whereas pharmacological reduction of glycolysis abrogates the excessive bone formation. Mechanistically, Notch reduces the expression of glycolytic and mitochondrial Complex I genes, resulting in a decease in mitochondrial respiration, superoxide production and Ampk activity. Forced activation of Ampk restores glycolysis in the face of Notch signaling. Thus, suppression of glucose metabolism contributes to the mechanism whereby Notch restricts osteoblastogenesis from bone marrow mesenchymal progenitors.

Authors

Seung-Yon Lee, Fanxin Long

Cigarette smoke and HIV synergistically affect lung pathology in cynomolgus macaques

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Abstract

In the era of combined antiretroviral therapy (cART), lung diseases such as chronic bronchitis (CB) and COPD are common among persons living with HIV (PLWH), particularly smokers. Although smoking is highly prevalent among PLWH, HIV may be an independent risk factor for lung diseases; however, the role of HIV and cigarette smoke (CS) and their potential interaction in the development of chronic lung diseases among PLWH has not been delineated. To investigate this interaction, cynomolgus macaques were exposed to CS and/or simian-adapted human immunodeficiency virus (SHIV) and treated with cART. The development of CB and the lung functions were evaluated following CS±SHIV treatment. The results showed that in the lung, SHIV was a strong independent risk factor for goblet cell metaplasia/hyperplasia and mucus formation, MUC5AC synthesis, loss of tight junction proteins, and increased expression of Th2 cytokines/transcription factors. In addition, SHIV and CS synergistically reduced the lung function and increased the extrathoracic tracheal ring thickness. Interestingly, SHIV-infection generated significant numbers of HIV-gp120+ epithelial cells (HGECs) in small airways and alveoli and their numbers doubled in CS+SHIV-infected lungs. We conclude that even with cART, SHIV independently induces CB and pro-COPD changes in the lung and the effects are exacerbated by CS.

Authors

Hitendra S. Chand, Rodrigo Vazquez-Guillamet, Christopher M. Royer, Karin Rudolph, Neerad C. Mishra, Shashi P. Singh, Shah S. Hussain, Edward G. Barrett, Shannon Callen, Siddappa N. Byrareddy, Maria Cristina Vazquez Guillamet, Jawad Abukhalaf, Aryaz Sheybani, Vernat Exil, Veena Raizada, Hemant Agarwal, Madhavan Nair, Francois Villinger, Shilpa Buch, Mohan Sopori

CD84 regulates PD-1/PD-L1 expression and function in chronic lymphocytic leukemia

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Abstract

Chronic lymphocytic leukemia (CLL) is characterized by clonal proliferation and progressive accumulation of mature, B lymphocytes in the peripheral blood, lymphoid tissues and bone marrow. CLL is characterized by profound immune defects, leading to severe infectious complications. T cells are numerically, phenotypically, and functionally highly abnormal in CLL, with only limited ability to exert antitumor immune responses. Exhaustion of T cells has also been implicated as playing an important role in anti-tumor responses. The CLL-mediated T cell exhaustion is achieved by aberrant expression of several inhibitory molecules on CLL and their environment, prominently the PD-L1/PD-1 receptors. Previously, we showed that CD84, a member of the SLAM family of receptors, bridges between CLL cells and their microenvironment. In the current study, we followed CD84 regulation of T cell function. We showed that a cell-cell interaction mediated through human and mouse CD84 upregulates PDL1 expression on CLL and their microenvironment, and PD1 expression on T cells. This resulted in suppression of T cell response and activity in vitro and in vivo. Thus, our results demonstrated a role for CD84 in regulation of immune checkpoints by leukemia cells, and suggested CD84 blockade as a therapeutic strategy to reverse tumor-induced immune suppression.

Authors

Hadas Lewinsky, Avital F. Barak, Victoria Huber, Matthias P. Kramer, Lihi Radomir, Lital Sever, Irit Orr, Vita Mirkin, Nili Dezorella, Mika Shapiro, Yosef Cohen, Lev Shvidel, Martina Seiffert, Yair Herishanu, Shirly Becker-Herman, Idit Shachar

Tumor-derived microRNAs induce myeloid suppressor cells and predict immunotherapy resistance in melanoma

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Abstract

The accrual of myeloid-derived suppressor cells (MDSCs) represents a major obstacle to effective immunotherapy in cancer patients, but the mechanisms underlying this process in the human setting remain elusive. Here, we describe a set of microRNAs (miR-146a, miR-155, miR-125b, miR-100, let-7e, miR-125a, miR-146b, miR-99b) that are associated with MDSCs and with resistance to treatment with immune checkpoint inhibitors in melanoma patients. The miRs were identified by transcriptional analyses as being responsible for the conversion of monocytes into MDSCs (CD14+HLA-DRneg cells) mediated by melanoma extracellular vesicles (EVs) and were shown to recreate MDSC features upon transfection. In melanoma patients, these miRs are increased in circulating CD14+ monocytes, plasma and tumor samples, where they correlate with the myeloid cell infiltrate. In plasma, their baseline level clusters with the clinical efficacy of CTLA-4 or PD-1 blockade. Hence, MDSC-related miRs represent an indicator of MDSC activity in cancer patients and a potential blood marker of a poor immunotherapy outcome.

Authors

Veronica Huber, Viviana Vallacchi, Viktor Fleming, Xiaoying Hu, Agata Cova, Matteo Dugo, Eriomina Shahaj, Roberta Sulsenti, Elisabetta Vergani, Paola Filipazzi, Angela De Laurentiis, Luca Lalli, Lorenza Di Guardo, Roberto Patuzzo, Barbara Vergani, Elena Casiraghi, Mara Cossa, Ambra Gualeni, Valentina Bollati, Flavio Arienti, Filippo De Braud, Luigi Mariani, Antonello Villa, Peter Altevogt, Viktor Umansky, Monica Rodolfo, Licia Rivoltini

PLK1 stabilizes a MYC-dependent kinase network in aggressive B cell lymphomas

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Abstract

Concordant activation of MYC and BCL-2 oncoproteins in double-hit lymphoma (DHL) results in aggressive disease that is refractory to treatment. By integrating activity-based proteomic profiling and drug screens, polo-like kinase-1 (PLK1) was identified as an essential regulator of the MYC-dependent kinome in DHL. Notably, PLK1 was expressed at high levels in DHL, correlated with MYC expression and connoted poor outcome. Further, PLK1 signaling augmented MYC protein stability and, in turn, MYC directly induced PLK1 transcription, establishing a feed-forward MYC-PLK1 circuit in DHL. Finally, inhibition of PLK1 triggered degradation of MYC and of the anti-apoptotic protein MCL1, and PLK1 inhibitors showed synergy with BCL-2 antagonists in blocking DHL cell growth, survival and tumorigenicity, supporting clinical targeting of PLK1 in DHL.

Authors

Yuan Ren, Chengfeng Bi, Xiaohong Zhao, Tint Lwin, Cheng Wang, Ji Yuan, Ariosto S. Silva, Bijal D. Shah, Bin Fang, Tao Li, John M. Koomen, Huijuan Jiang, Julio C. Chavez, Lan Pham, Praneeth R. Sudalagunta, Lixin Wan, Xuefeng Wang, William S. Dalton, Lynn C. Moscinski, Kenneth H. Shain, Julie Vose, John L. Cleveland, Eduardo M. Sotomayor, Kai Fu, Jianguo Tao

Airway Fractal Dimension Predicts Respiratory Morbidity and Mortality in COPD

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Abstract

BACKGROUND. Chronic obstructive pulmonary disease (COPD) is characterized by airway remodeling. Characterization of airway changes on computed tomography has been challenging due to the complexity of the recurring branching patterns, and this can be better measured using fractal dimensions. METHODS. We analyzed segmented airway trees of 8135 participants enrolled in the COPDGene cohort. The fractal complexity of the segmented airway tree was measured by the Airway Fractal Dimension (AFD) using the Minkowski-Bouligand box-counting dimension. We examined associations between AFD and lung function and respiratory morbidity using multivariable regression analyses. We further estimated the extent of peribronchial emphysema (%) within 5mm of the airway tree as this is likely to affect AFD. We classified participants into 4 groups based on median AFD and %peribronchial emphysema, and estimated survival. RESULTS. AFD was significantly associated with FEV1 (p<0.001) and FEV1/FVC (p<0.001) after adjusting for age, race, gender, smoking status, pack-years of smoking, body-mass-index, CT emphysema, air trapping, airway thickness, and CT scanner type. On multivariable analysis, AFD was also associated with respiratory-quality of life and six-minute walk distance, as well as exacerbations, lung function decline and mortality on longitudinal follow-up. We identified a subset of participants with AFDmedian who had worse survival compared with participants with high AFD and low peribronchial emphysema (adjusted HR = 2.72, 95%CI 2.20 to 3.35; p<0.001), a substantial number of whom were not identified by traditional spirometry severity grades. CONCLUSIONS. Airway fractal dimension as a measure of airway branching complexity and remodeling in smokers is associated with respiratory morbidity and lung function change, offers prognostic information additional to traditional CT measures of airway wall thickness, and can be used to estimate mortality risk.

Authors

Sandeep Bodduluri, Abhilash S. Kizhakke Puliyakote, Sarah E. Gerard, Joseph M. Reinhardt, Eric A. Hoffman, John D. Newell Jr., Hrudaya P. Nath, MeiLan K. Han, George R. Washko, Raúl San José Estépar, Mark T. Dransfield, Surya P. Bhatt