Prelamin A mediates inflammation in dilated and HIV associated cardiomyopathies

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Abstract

Cardiomyopathies are complex heart muscle diseases that can be inherited or acquired. Dilated cardiomyopathy can result from mutations in LMNA, encoding the nuclear intermediate filament proteins lamin A/C. Some LMNA mutations lead to accumulation of the lamin A precursor, prelamin A, which is disease causing in a number of tissues yet its impact upon the heart is unknown. Here we discovered myocardial prelamin A accumulation occurred in a case of dilated cardiomyopathy and show that a novel mouse model of cardiac specific prelamin A accumulation exhibited a phenotype consistent with ‘inflammatory cardiomyopathy’ which we observed to be similar to HIV associated cardiomyopathy, an acquired disease state. Numerous HIV protease therapies are known to inhibit ZMPSTE24, the enzyme responsible for prelamin A processing, and we confirmed that accumulation of prelamin A occurred in HIV+ patient cardiac biopsies. These findings: (1) confirm a unifying pathological role for prelamin A common to genetic and acquired cardiomyopathies; (2) have implications for the management of HIV patients with cardiac disease suggesting protease inhibitors should be replaced with alternative therapies i.e. non-nucleoside reverse transcriptase inhibitors; and (3) suggest that targeting inflammation may be a useful treatment strategy for certain forms of inherited cardiomyopathy.

Authors

Daniel Brayson, Andrea Frustaci, Romina Verardo, Cristina Chimenti, Matteo Antonio Russo, Robert Hayward, Sadia Munir Ahmad, Gema Vizcay-Barrena, Andrea Protti, Peter S. Zammit, Cristobal G. dos Remedios, Elisabeth Ehler, Ajay M. Shah, Catherine M. Shanahan

Keratinocyte-derived IκBζ drives psoriasis and associated systemic inflammation

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Abstract

The transcriptional activator IκBζ is a key regulator of psoriasis, but which cells mediate its pathogenic effect remains unknown. Here we found that IκBζ expression in keratinocytes triggers not only skin lesions, but also systemic inflammation in mouse psoriasis models. Specific depletion of IκBζ in keratinocytes was sufficient to suppress the induction of imiquimod- or IL-36-mediated psoriasis. Moreover, IκBζ ablation in keratinocytes prevented the onset of psoriatic lesions and systemic inflammation in keratinocyte-specific IL-17A transgenic mice. Mechanistically, this psoriasis protection was mediated by the fact that IκBζ deficiency in keratinocytes abrogated the induction of specific pro-inflammatory target genes, including Cxcl5, Cxcl2, Csf2 and Csf3, in response to IL-17A or IL-36. These IκBζ-dependent genes trigger the generation and recruitment of neutrophils and monocytes that are needed for skin inflammation. Consequently, our data uncover a surprisingly pivotal role of keratinocytes and keratinocyte-derived IκBζ as key mediators of psoriasis and psoriasis-related systemic inflammation.

Authors

Sebastian Lorscheid, Anne Müller, Jessica Löffler, Claudia Resch, Philip Bucher, Florian C. Kurschus, Ari Waisman, Knut Schäkel, Stephan Hailfinger, Klaus Schulze-Osthoff, Daniela Kramer

A unique mutator phenotype reveals complementary oncogenic lesions leading to acute leukemia

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Abstract

Mice homozygous for a hypomorphic allele of DNA replication factor minichromosome maintenance protein 2 (designated Mcm2cre/cre) develop precursor T-cell lymphoblastic leukemia/lymphoma (pre-T LBL) with 4-32 small interstitial deletions per tumor. Mice that express a NUP98-HOXD13 (NHD13) transgene develop multiple types of leukemia, including myeloid, T and B lymphocyte. All Mcm2cre/creNHD13+ mice develop pre-T LBL, and 26% develop an unrelated, concurrent B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Copy Number Alteration (CNA) analysis demonstrated that pre-T LBL were characterized by homozygous deletions of Pten and Tcf3, and partial deletions of Notch1 leading to Notch1 activation. In contrast, BCP-ALL were characterized by recurrent deletions involving Pax5 and Ptpn1, and copy number gain of Abl1 and Nup214 resulting in a Nup214-Abl1 fusion. We present a model in which Mcm2 deficiency leads to replicative stress, DNA double strand breaks, and resultant CNAs due to errors in DNA DSB repair. CNAs which involve critical oncogenic pathways are then selected in vivo as malignant lymphoblasts, due to a fitness advantage. Some CNAs, such as those involving Abl1 and Notch1, represent attractive targets for therapy.

Authors

Mianmian Yin, Timour Baslan, Robert L. Walker, Yuelin J. Zhu, Amy Freeland, Toshihiro Matsukawa, Sriram Sridharan, André Nussenzweig, Steven C. Pruitt, Scott W. Lowe, Paul S. Meltzer, Peter D. Aplan

Rb1/Rbl1/Vhl loss induces mouse subretinal angiomatous proliferation and hemangioblastoma

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Abstract

Von Hippel–Lindau (Vhl) protein inhibits hypoxia-inducible factor (Hif), yet its deletion in murine retina does not cause the extensive angiogenesis expected with Hif induction. The mechanism is unclear. Here we show that retinoblastoma tumor suppressor (Rb1) constrains expression of Hif target genes in the Vhl-/- retina. Deleting Rb1 induced extensive retinal neovascularization and autophagic ablation of photoreceptors in the Vhl-/- retina. RNA sequencing, ChIP and reporter assays showed Rb1 recruitment to and repression of certain Hif target genes. Activating Rb1 by deleting cyclin D1 induced a partial defect in the retinal superficial vascular plexus (SVP). Unexpectedly, removing Vhl suppressed retinoblastoma formation in murine Rb1/Rbl1-deficient retina, but generated subretinal vascular growths resembling retinal angiomatous proliferation (RAP), and retinal capillary hemangioblastoma (RCH). Most stromal cells in the RAP/RCH-like lesions were Sox9+, suggesting a Müller glia origin, and expressed Lgals3, a marker of human brain hemangioblastoma. Thus, the Rb family limit Hif target gene expression in the Vhl-/- retina, and removing this inhibitory signal generates new models for RAP and RCH.

Authors

Ran Wei, Xiang Ren, Hongyu Kong, Zhongping Lv, Yongjiang Chen, Yunjing Tang, Yujiao Wang, Lirong Xiao, Sabiha Hacibekiroglu, Chen Liang, Andras Nagy, Rod Bremner, Danian Chen

Genetic deficiency or pharmacological inhibition of miR-33 protects from kidney fibrosis

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Abstract

Previous work has reported the important links between cellular bioenergetics and the development of chronic kidney disease, highlighting the potential for targeting metabolic functions to regulate disease progression. More recently, it has been shown that alterations in fatty acid oxidation (FAO) can have an important impact on the progression of kidney disease. In this work, we demonstrate that loss of miR-33, an important regulator of lipid metabolism, can prevent the repression of FAO in fibrotic kidneys and reduce lipid accumulation. These changes were associated with a dramatic reduction in the extent of fibrosis induced in two different mouse models of kidney disease. These effects were not related to changes in circulating leukocytes, as bone marrow transplant from miR-33 deficient animals did not have a similar impact on disease progression. Most importantly, targeted delivery of miR-33 peptide nucleic acid (PNA) inhibitors to the kidney and other acidic microenvironments was accomplished using pH low insertion peptides (pHLIP) as a carrier. This was effective at both increasing the expression of factors involved in FAO and reducing the development of fibrosis. Together, these findings suggest that miR-33 may be an attractive therapeutic target for the treatment of chronic kidney disease.

Authors

Nathan L. Price, Verónica Miguel, Wen Ding, Abhishek K. Singh, Shipra Malik, Noemi Rotllan, Anna Moshnikova, Jakub Toczek, Caroline Zeiss, Mehran M. Sadeghi, Noemi Arias, Ángel Baldán, Oleg A. Andreev, Diego Rodríguez-Puyol, Raman Bahal, Yana K. Reshetnyak, Yajaira Suárez, Carlos Fernández-Hernando, Santiago Lamas

Transcriptional regulatory model of fibrosis progression in the human lung

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Abstract

To develop a systems biology model of fibrosis progression within the human lung we performed RNAseq and microRNA analysis on 95 samples obtained from 10 idiopathic pulmonary fibrosis (IPF) and 6 control lungs. Extent of fibrosis in each sample was assessed by microCT measured alveolar surface density (ASD) and confirmed by histology. Regulatory gene expression networks were identified using linear mixed-effect models and dynamic regulatory events miner (DREM). Differential gene expression analysis identified a core set of genes increased or decreased before fibrosis was histologically evident that continued to change with advanced fibrosis. DREM generated a systems biology model of fibrosis progression (available at http: www.sb.cs.cmu.edu/IPFReg) that identified progressively divergent gene expression tracks with microRNAs and transcription factors that specifically regulate early or advanced fibrosis. We confirmed model predictions by demonstrating that expression of POU2AF1, previously unassociated with lung disease but proposed by the model as regulator, is increased in B-lymphocytes in IPF lungs and that POU2AF1 knockout mice were protected from bleomycin induced lung fibrosis. Our results reveal distinct regulation of gene expression changes in IPF tissue that remained structurally normal compared with moderate or advanced fibrosis and suggest distinct regulatory mechanisms for each stage.

Authors

John E. McDonough, Farida Ahangari, Qin Li, Siddhartha Jain, Stijn E. Verleden, Jose Herazo-Maya, Milica Vukmirovic, Giuseppe DeIuliis, Argyrios Tzouvelekis, Naoya Tanabe, Fanny Chu, Xiting Yan, Johny Verschakelen, Robert J. Homer, Dimitris V. Manatakis, Junke Zhang, Jun Ding, Karen Maes, Laurens De Sadeleer, Robin Vos, Arne Neyrinck, Panayiotis V. Benos, Ziv Bar-Joseph, Dean Tantin, James C. Hogg, Bart M. Vanaudenaerde, Wim A. Wuyts, Naftali Kaminski

Sonic hedgehog connects podocyte injury to mesangial activation and glomerulosclerosis

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Abstract

Glomerular disease is characterized by proteinuria and glomerulosclerosis, two pathologic features caused by podocyte injury and mesangial cell activation, respectively. However, whether these two events are linked remains elusive. Here, we report that sonic hedgehog (Shh) is the mediator that connects podocyte damage to mesangial activation and glomerulosclerosis. Shh was induced in glomerular podocytes in various models of proteinuric chronic kidney diseases (CKD). However, mesangial cells in the glomeruli, but not podocytes, responded to hedgehog ligand. In vitro, Shh was induced in podocytes after injury and selectively promoted mesangial cell activation and proliferation. In a mini-organ culture of isolated glomeruli, Shh promoted mesangial activation but did not affect the integrity of podocytes. Podocyte-specific ablation of Shh in vivo exhibited no effect on proteinuria after adriamycin injection but hampered mesangial activation and glomerulosclerosis. Consistently, pharmacologic blockade of Shh signaling decoupled proteinuria from glomerulosclerosis. In humans, Shh was upregulated in glomerular podocytes in patients with CKD and its circulating level was associated with glomerulosclerosis but not proteinuria. These studies demonstrate that Shh mechanistically links podocyte injury to mesangial activation in the pathogenesis of glomerular diseases. Our findings also illustrate a crucial role for podocyte-mesangial communication in connecting proteinuria to glomerulosclerosis.

Authors

Dong Zhou, Haiyan Fu, Yang Han, Lu Zhang, Shijia Liu, Lin Lin, Donna B. Stolz, Youhua Liu

Enapotamab vedotin, an AXL-specific antibody-drug conjugate, shows preclinical antitumor activity in non-small cell lung cancer

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Abstract

Targeted therapies and immunotherapy have shown promise in patients with non-small cell lung cancer (NSCLC). However, the majority of patients fail or become resistant to treatment, emphasizing the need for novel treatments. In this study, we confirm the prognostic value of AXL levels in NSCLC and demonstrate potent anti-tumor activity of the AXL-targeting antibody-drug conjugate enapotamab vedotin across different NSCLC subtypes in a mouse clinical trial of human NSCLC. Tumor regression or stasis was observed in 17/61 (28%) of the PDX models, and was associated with AXL mRNA expression levels. Significant single agent activity of enapotamab vedotin was validated in vivo in 9 of 10 AXL-expressing NSCLC xenograft models. In a panel of EGFR-mutant NSCLC cell lines rendered resistant to EGFR inhibitors (EGFRi) in vitro, we observed de novo or increased AXL protein expression concomitant with enapotamab vedotin-mediated cytotoxicity. Enapotamab vedotin also showed anti-tumor activity in vivo in 3 EGFR-mutant, EGFRi-resistant PDX models, including an osimertinib-resistant NSCLC PDX model. In summary, enapotamab vedotin has promising therapeutic potential in NSCLC. The safety and preliminary efficacy of enapotamab vedotin are currently being evaluated in the clinic across multiple solid tumor types, including NSCLC.

Authors

Louise A. Koopman, Mikkel G. Terp, Gijs G. Zom, Maarten L. Janmaat, Kirstine Jacobsen, Elke Gresnigt - Van den Heuvel, Marcel Brandhorst, Ulf Forssmann, Frederik M. de Bree, Nora Pencheva, Andreas Lingnau, Maria A. Zipeto, Paul W.H.I. Parren, Esther C.W. Breij, Henrik J. Ditzel

MiR-16 regulates crosstalk in NF-kB tolerogenic inflammatory signaling between myeloma cells and bone marrow macrophages

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Abstract

High levels of circulating miR-16 in the serum of multiple myeloma (MM) patients are independently associated with longer survival. Although the tumor suppressor function of intracellular miR-16 in cancer cells, including MM plasma cells (PCs), has been highly elucidated, its extracellular role in maintaining a non-supportive cancer microenvironment has not been fully explored. Here, we show that miR-16 can be actively secreted by MM cells through extracellular vesicles (EVs), and its extracellular and intracellular levels are directly correlated. We also show that EVs isolated from MM patients and from the conditioned media of MM-PCs can differentiate circulating monocytes to M2-tumor supportive macrophages (TAMs) and that the presence of higher levels of extracellular miR-16 counteracts this effect. In agreement with these observations, our data show that miR-16 directly targets the IKKα/β complex of the NF-kB canonical pathway, which is known to play a critical role in polarizing macrophages toward an M2 phenotype. By using a miR-15a-16-1 knockout mouse model, we also show that loss of the miR-16 cluster supports polarization to M2-macrophages. Finally, we demonstrate the therapeutic benefit of miR-16 overexpression in potentiating the anti-MM activity by a proteasome inhibitor in the presence of MM resident bone marrow TAM.

Authors

Jihane Khalife, Jayeeta Ghose, Marianna Martella, Domenico Viola, Alberto Rocci, Estelle Troadec, Cesar Terrazas, Abhay R. Satoskar, Emine Gulsen Gunes, Ada Dona, James F. Sanchez, P. Leif Bergsagel, Marta Chesi, Alex Pozhitkov, Steven Rosen, Guido Marcucci, Jonathan J. Keats, Craig C. Hofmeister, Amrita Krishnan, Enrico Caserta, Flavia Pichiorri

Bitopertin, a selective oral GLYT1 inhibitor, improves anemia in a mouse model of beta-thalassemia

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Abstract

Anemia of β-thalassemias is caused by ineffective erythropoiesis and reduced red cell survival. Several lines of evidence indicate that iron/heme restriction is a potential therapeutic strategy for the disease. Glycine is a key initial substrate for heme and globin synthesis. We provide evidence that bitopertin, a glycine transport inhibitor administered orally, improves anemia, reduces hemolysis, diminishes ineffective erythropoiesis, and increases red cell survival in a mouse model of β-thalassemia (Hbbth3/+ mice). Bitopertin ameliorates erythroid oxidant damage as indicated by a reduction in membrane-associated free α–globin chain aggregates, in reactive oxygen species cellular content, in membrane-bound hemichromes and in HRI activation and elF2α phosphorylation. The improvement of β-thalassemic ineffective erythropoiesis is associated with diminished mTOR activation, Rab5, Lamp1, and p62 accumulation, indicating an improved autophagy. Bitopertin also upregulates liver hepcidin and diminishes liver iron overload. The hematologic improvements achieved by bitopertin are blunted by the concomitant administration of the iron chelator deferiprone, suggesting that an excessive restriction of iron availability might negate the beneficial effects of bitopertin. These data provide important and clinically relevant insights into glycine restriction and reduced heme synthesis strategies for the treatment of β-thalassemia.

Authors

Alessandro Matte, Enrica Federti, Michael Winter, Annette Koerner, Anja Harmeier, Norman Mazer, Tomas Tomka, Maria Luisa Di Paolo, Luigia De Falco, Immacolata Andolfo, Elisabetta Beneduce, Achille Iolascon, Alejandra Macias-Garcia, Jane-Jane Chen, Anne Janin, Christophe Leboeuf, Francesco Turrini, Carlo Brugnara, Lucia De Franceschi