Germline or somatic loss-of-function mutations of fumarate hydratase (FH) predispose patients to an aggressive form of renal cell carcinoma (RCC). Since other than tumor resection, there is no effective therapy for metastatic FH-deficient RCC, an accurate method for early diagnosis is needed. Although MRI or CT scans are offered, they cannot differentiate FH-deficient tumors from other RCCs. Therefore, finding noninvasive plasma biomarkers suitable for rapid diagnosis, screening and surveillance would improve clinical outcomes. Taking advantage of the robust metabolic rewiring that occurs in FH-deficient cells, we performed plasma metabolomics analysis and identified two tumor-derived metabolites, succinyl-adenosine and succinic-cysteine, as outstanding plasma biomarkers for early diagnosis (receiver operating characteristic area under curve (ROCAUC) = 0.98). These two molecules reliably reflected the FH mutation status and tumor mass. We further identified the enzymatic cooperativity by which these biomarkers are produced within the tumor microenvironment. Longitudinal monitoring of patients demonstrated that these circulating biomarkers can be used for reporting on treatment efficacy and identifying recurrent or metastatic tumors.
Liang Zheng, Zi-Ran Zhu, Tal Sneh, Weituo Zhang, Zao-Yu Wang, Guang-Yu Wu, Wei He, Hong-Gang Qi, Hang Wang, Xiao-Yu Wu, Jonatan Fernández-García, Ifat Abramovich, Yun-Ze Xu, Jin Zhang, Eyal Gottlieb
Many hepatocellular carcinoma (HCC) patients do not respond to the first-line immune checkpoint inhibitor treatment. Immunization with effective cancer vaccines is an attractive alternative approach to immunotherapy. However, its efficacy remains insufficiently evaluated in preclinical studies. Here, we investigated HCC-associated self/tumor antigen, α-fetoprotein (AFP) based vaccine immunization for treating AFP (+) HCC mouse models. We found that AFP immunization effectively induced AFP-specific CD8+ T cells in vivo. However, these CD8+ T cells expressed exhaustion markers, including PD1, LAG3, and Tim3. Furthermore, the AFP vaccine effectively prevented c-MYC/Mcl1 HCC initiation when administrated before tumor formation, while it was ineffective against full-blown c-MYC/Mcl1 tumors. Similarly, anti-PD1 and anti-PD-L1 monotherapy showed no efficacy in this murine HCC model. In striking contrast, AFP immunization combined with anti-PD-L1 treatment triggered significant inhibition of HCC progression in most liver tumor nodules, while combining with anti-PD1 induced slower tumor progression. Mechanistically, we demonstrated that HCC intrinsic PD-L1 expression was the primary target of anti-PD-L1 in this combination therapy. Notably, the combination therapy had a similar therapeutic effect in the cMet/β-Catenin mouse HCC model. These findings suggest that combining the AFP vaccine and immune checkpoint inhibitors may be effective for AFP (+) HCC treatment.
Xinjun Lu, Shanshan Deng, Jiejie Xu, Benjamin L. Green, Honghua Zhang, Guofei Cui, Yi Zhou, Yi Zhang, Hongwei Xu, Fapeng Zhang, Rui Mao, Sheng Zhong, Thorsten Cramer, Matthias Evert, Diego F. Calvisi, Yukai He, Chao Liu, Xin Chen
BACKGROUND. The stomach-derived hormone ghrelin stimulates appetite, but the ghrelin receptor is also expressed in brain circuits involved in motivation and reward. We examined ghrelin effects on decision making beyond food or drug rewards, using monetary outcomes. METHODS. Thirty participants (50% females) underwent two fMRI scans, in randomized counterbalanced order, while receiving intravenous ghrelin or saline. RESULTS. Striatal representations of reward anticipation were unaffected by ghrelin, while activity during anticipation of losses was attenuated. Temporal discounting rates of monetary rewards were lower overall in the ghrelin condition, an effect driven by women. Discounting rates were inversely correlated with neural activity in a large cluster within the left parietal lobule that included the angular gyrus. Activity in an overlapping cluster was related to behavioral choices, and was suppressed by ghrelin. CONCLUSION. This is to our knowledge the first human study to extend the understanding of ghrelin’s significance beyond the canonical feeding domain or in relation to addictive substances. Contrary to our hypothesis, we find that ghrelin does not affect sensitivity to monetary reward anticipation, but rather results in attenuated loss aversion and lower discounting rates for these rewards. Ghrelin may cause a motivational shift toward caloric rewards rather than globally promoting the value of rewards. TRIAL REGISTRATION. EudraCT 2018-004829-82 FUNDING. Swedish Research Council (MH: 2013-07434) and Marcus and Marianne Wallenberg foundation (GT: 2014.0187). Author LL is supported by NIDA/NIAAA IRP
Michal Pietrzak, Adam Yngve, J. Paul Hamilton, Robin Kämpe, Rebecca Boehme, Anna Asratian, Emelie Gauffin, Andreas Löfberg, Sarah Gustavson, Emil Persson, Andrea J. Capusan, Lorenzo Leggio, Irene Perini, Gustav Tinghög, Markus Heilig
Kara N. Thomas, Nimisha Srikanth, Sanat S. Bhadsavle, Kelly R. Thomas, Katherine N. Zimmel, Alison Basel, Alexis N. Roach, Nicole A. Mehta, Yudhishtar S. Bedi, Michael C. Golding
Excessive Erythrocytosis (EE) is a major hallmark of patients suffering from chronic mountain sickness (CMS, Monge’s disease) and is responsible for major morbidity and even mortality in early adulthood. We took advantage of unique populations, one living at high altitude (Peru) showing EE, while another population, at the same altitude and region, shows no evidence of EE (non-CMS). Through RNA-seq, we identified and validated the function of a group of long non-coding RNA (lncRNAs) that regulate erythropoiesis in Monge’s disease but not in the non-CMS population. Among these lncRNAs is HIKER (Hypoxia Induced Kinase-mediated Erythropoietic Regulator)/LINC02228 which we showed plays a critical role in erythropoiesis in CMS cells. Under hypoxia, HIKER modulated CSNK2B (the regulatory subunit of Casein kinase 2). A down-regulation of HIKER down-regulated CSNK2B, remarkably reducing erythropoiesis (<70% reduction of BFUs); furthermore, an up-regulation of CSNK2B on the background of HIKER down-regulation rescued erythropoiesis defects. Pharmacologic inhibition of CSNK2B drastically reduced erythroid colonies (50-75% reduction in BFU colonies) and knock-down of CSNK2B in zebrafish lead to a defect in hemoglobinization (<97% morphants show reduction in hemoglobin levels). We conclude that HIKER regulates erythropoiesis in Monge’s disease and acts through at least one specific target, CSNK2B, a casein kinase.
Priti Azad, Dan Zhou, Hung-Chi Tu, Francisco C. Villafuerte, David Traver, Tariq M. Rana, Gabriel G. Haddad
Current therapies for Fabry disease are based on reversing intra-cellular accumulation of globotriaosylceramide (Gb3) by enzyme replacement therapy (ERT) or chaperone-mediated stabilization of the defective enzyme, thereby alleviating lysosome dysfunction. However, their effect in the reversal of end-organ damage, like kidney injury and chronic kidney disease remains unclear. First, ultrastructural analysis of serial human kidney biopsies showed that long-term use of ERT reduced Gb3 accumulation in podocytes but did not reverse podocyte injury. Then, a CRISPR/CAS9-mediated α-Galactosidase knockout podocyte cell line confirmed ERT-mediated reversal of Gb3 accumulation without resolution of lysosomal dysfunction. Transcriptome-based connectivity mapping and SILAC-based quantitative proteomics identified alpha-synuclein (SNCA) accumulation as a key event mediating podocyte injury. Genetic and pharmacological inhibition of SNCA improved lysosomal structure and function in Fabry podocytes, exceeding the benefits of ERT. Together, this work reconceptualizes Fabry-associated cell injury beyond Gb3 accumulation, and introduces SNCA modulation as a potential intervention, especially for patients with Fabry nephropathy.
Fabian Braun, Ahmed Abed, Dominik Sellung, Manuel Rogg, Mathias Woidy, Oysten Eikrem, Nicola Wanner, Jessica Gambardella, Sandra D. Laufer, Fabian Haas, Milagros N. Wong, Bernhard Dumoulin, Paula Rischke, Anne K. Mühlig, Wiebke Sachs, Katharina von Cossel, Kristina Schulz, Nicole Muschol, Sören W. Gersting, Ania C. Muntau, Oliver Kretz, Oliver Hahn, Markus M. Rinschen, Michael Mauer, Tillmann Bork, Florian Grahammer, Wei Liang, Thorsten Eierhoff, Winfried Römer, Arne Hansen, Catherine Meyer-Schwesinger, Guido Iaccarino, Camilla Tøndel, Hans-Peter Marti, Behzad Najafian, Victor G. Puelles, Christoph Schell, Tobias B. Huber
Programmed death ligand 1 (PD-L1) is an immune checkpoint protein frequently expressed in human cancers, which contributes to immune evasion through its binding to PD-1 on activated T cells. Unveiling the mechanisms underlying PD-L1 expression is essential for understanding the impacts of immunosuppressive microenvironment, and also crucial for the purpose of re-boosting anti-tumour immunity. However, how PD-L1 is regulated, particularly at translational levels, remains largely unknown. Here, we discovered that a lncRNA, HIF-1α inhibitor at translation level (HITT), was transactivated by E2F1 under interferon-γ stimulation. It bound and co-ordinated with Regulator of G Protein Signalling 2 (RGS2) in binding to the 5ʹ-untranslated region (UTR) of PD-L1, resulting in reduced PD-L1 translation. HITT expression enhanced T cell-mediated cytotoxicity both in vitro and in vivo in a PD-L1 dependent manner. The clinical correlation between HITT/PD-L1, RGS2/PD-L1 expression was also detected in breast cancer tissues. Together, these findings demonstrate the role of HITT in antitumour T cell immunity, highlighting activation of HITT as a potential therapeutic strategy to enhance cancer immunotherapy.
Qingyu Lin, Tong Liu, Xingwen Wang, Guixue Hou, Zhiyuan Xiang, Wenxin Zhang, Shanliang Zheng, Dong Zhao, Qibin Leng, Xiaoshi Zhang, Minqiao Lu, Tianqi Guan, Hao Liu, Ying Hu
Despite advances in acute care, ischemic stroke remains a major cause of long-term disability. Approaches targeting both neuronal and glial responses are needed to enhance recovery and improve long-term outcome. The complement C3a receptor (C3aR) is a regulator of inflammation with roles in neurodevelopment, neural plasticity, and neurodegeneration. Using mice lacking C3aR (C3aR–/–) and mice overexpressing C3a in the brain, we uncovered two opposing effects of C3aR signaling on functional recovery after ischemic stroke: inhibition in the acute phase and facilitation in the later phase. Peri-infarct astrocyte reactivity was increased and density of microglia reduced in C3aR–/– mice, C3a overexpression led to the opposite effects. Pharmacological treatment of wild-type mice with intranasal C3a starting 7 days after stroke accelerated recovery of motor function and attenuated astrocyte reactivity without enhancing microgliosis. C3a treatment stimulated global white matter reorganization, increased peri-infarct structural connectivity and upregulated Igf1 and Thbs4 in the peri-infarct cortex. Thus, C3a treatment from day 7 after stroke exerts positive effects on astrocytes and neuronal connectivity while avoiding the deleterious consequences of C3aR signaling during the acute phase. Intranasal administration of C3aR agonists within convenient time window holds translational promise to improve outcome after ischemic stroke.
Anna Stokowska, Markus Aswendt, Daniel Zucha, Stephanie Lohmann, Frederique Wieters, Javier Moran Suarez, Alison L. Atkins, YiXian Li, Maria Miteva, Julia Lewin, Dirk Wiedermann, Michael Diedenhofen, Åsa Torinsson Naluai, Pavel Abaffy, Lukas Valihrach, Mikael Kubista, Mathias Hoehn, Milos Pekny, Marcela Pekna
Duchenne muscular dystrophy (DMD) is a lethal muscle disease caused by absence of the protein dystrophin, which acts as a structural link between the basal lamina and contractile machinery to stabilize muscle membranes from mechanical stress. In DMD, mechanical stress leads to exaggerated membrane injury and fiber breakdown, with fast fibers being the most susceptible to damage. A major contributor to this injury is muscle contraction, controlled by the motor protein myosin. However, the relationship between how muscle contraction and fast muscle fiber damage contribute to the pathophysiology of DMD has not been well characterized. We explored the role of fast skeletal muscle contraction in DMD with a novel, selective, orally active inhibitor of fast skeletal muscle myosin, EDG-5506. Surprisingly, even modest decreases of contraction (<15%) were sufficient to protect skeletal muscles in dystrophic mdx mice from stress injury. Longer-term treatment also decreased muscle fibrosis in key disease-implicated tissues. Importantly, therapeutic levels of myosin inhibition with EDG-5506 did not detrimentally affect strength or coordination. Finally, in dystrophic dogs, EDG-5506 reversibly reduced circulating muscle injury biomarkers and increased habitual activity. This unexpected biology may represent an important alternative treatment strategy for Duchenne and related myopathies.
Alan J. Russell, Mike DuVall, Benjamin Barthel, Ying Qian, Angela K. Peter, Breanne L. Newell-Stamper, Kevin Hunt, Sarah J. Lehman, Molly R. Madden, Stephen T. Schlachter, Benjamin D. Robertson, Ashleigh Van Deusen, Hector M. Rodriguez, Carlos D. Vera, Yu Su, Dennis R. Claflin, Susan V. Brooks, Peter P. Nghiem, Alexis Rutledge, Twlya I. Juehne, Jinsheng Yu, Elisabeth R. Barton, Yangyi E. Luo, Andreas Patsalos, Laszlo Nagy, H. Lee Sweeney, Leslie A. Leinwand, Kevin Koch
Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy that harbors mutations in homologous recombination (HR) repair proteins in 20-25% of cases. Defects in HR impart to tumor cells a specific vulnerability to poly-ADP ribose polymerase inhibitors and platinum-containing chemotherapy. However, not all patients who receive these therapies respond, and many who initially respond ultimately develop resistance. Inactivation of the HR pathway is associated with the overexpression of polymerase theta (Polθ, or POLQ). This key enzyme regulates the microhomology-mediated end-joining (MMEJ) pathway of double-strand break (DSB) repair. Using human and murine HR-deficient PDAC models, we find that POLQ knockdown is synthetically lethal with mutations in HR genes (BRCA1 and BRCA2) and the DNA damage repair gene ATM. Further, POLQ knockdown enhances cytosolic micronuclei formation and activates cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling, leading to enhanced infiltration of activated CD8+ T cells in BRCA2-deficient PDAC tumors in vivo. Overall, POLQ, a key mediator in the MMEJ pathway, is critical for DSB repair in BRCA2-deficient PDAC. Its inhibition represents a synthetic lethal approach to block tumor growth while simultaneously stimulating an immune response.
Grace Oh, Annie Wang, Lidong Wang, Jiufeng Li, Gregor Werba, Daniel Weissinger, Ende Zhao, Surajit Dhara, Rosmel E. Hernandez, Amanda Ackermann, Sarina Porcella, Despoina Kalfakakou, Igor Dolgalev, Emily A. Kawaler, Talia Golan, Theodore H. Welling, Agnel Sfeir, Diane M. Simeone
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