Just as the androgen receptor (AR), the estrogen receptor α (ERα) is expressed in the prostate and is thought to influence prostate cancer (PCa) biology. Yet, the incomplete understanding of ERα functions in PCa hinders our ability to fully comprehend its clinical relevance and restricts the repurposing of estrogen-targeted therapies for the treatment of this disease. Using two human PCa tissue microarray cohorts, we first demonstrated that nuclear ERα expression was heterogeneous among patients, being only detected in half of tumors. Positive nuclear ERα levels were correlated with disease recurrence, progression to metastatic PCa, and patient survival. Using in vitro and in vivo models of the normal prostate and PCa, bulk and single-cell RNA-Seq analyses revealed that estrogens partially mimic the androgen transcriptional response and induce specific biological pathways linked to proliferation and metabolism. Bioenergetic flux assays and metabolomics confirmed the regulation of cancer metabolism by estrogens, supporting proliferation. Using cancer cell lines and patient-derived organoids, selective estrogen receptor modulators, a pure anti-estrogen, and genetic approaches impaired cancer cell proliferation and growth in an ERα-dependent manner. Overall, our study revealed that, when expressed, ERα functionally reprograms PCa metabolism, is associated with disease progression, and could be targeted for therapeutic purposes.
Camille Lafront, Lucas Germain, Gabriel H. Campolina-Silva, Cindy Weidmann, Line Berthiaume, Hélène Hovington, Hervé Brisson, Cynthia Jobin, Lilianne Frégeau-Proulx, Raul Cotau, Kevin Gonthier, Aurélie Lacouture, Patrick Caron, Claire Ménard, Chantal Atallah, Julie Riopel, Éva Latulippe, Alain Bergeron, Paul Toren, Chantal Guillemette, Martin Pelletier, Yves Fradet, Clémence Belleannée, Frédéric Pouliot, Louis Lacombe, Éric Lévesque, Étienne Audet-Walsh
Tissue regeneration is limited in several organs including the kidney, contributing to the high prevalence of kidney disease globally. However, evolutionary and physiological adaptive responses and the presence of renal progenitor cells suggest existing remodeling capacity. This study uncovered endogenous tissue remodeling mechanisms in the kidney that were activated by the loss of body fluid and salt and regulated by a unique niche of a minority renal cell type called the macula densa (MD). Here we identified neuronal differentiation features of MD cells that sense the local and systemic environment, secrete angiogenic, growth and extracellular matrix remodeling factors, cytokines and chemokines, and control resident progenitor cells. Serial intravital imaging, MD nerve growth factor receptor and Wnt mouse models and transcriptome analysis revealed cellular and molecular mechanisms of these MD functions. Human and therapeutic translation studies illustrated the clinical potential of MD factors including CCN1 as a urinary biomarker and therapeutic target in chronic kidney disease. The concept that a neuronally differentiated key sensory and regulatory cell type responding to organ-specific physiological inputs controls local progenitors to remodel or repair tissues may be applicable to other organs and diverse tissue regenerative therapeutic strategies.
Georgina Gyarmati, Urvi Nikhil Shroff, Anne Riquier-Brison, Dorinne Desposito, Wenjun Ju, Sean D. Stocker, Audrey Izuhara, Sachin Deepak, Alejandra Becerra Calderon, James L. Burford, Hiroyuki Kadoya, Ju-Young Moon, Yibu Chen, Markus M. Rinschen, Nariman Ahmadi, Lester Lau, Daniel Biemesderfer, Aaron W. James, Liliana Minichiello, Berislav Zlokovic, Inderbir S. Gill, Matthias Kretzler, János Peti-Peterdi
Individuals with clonal hematopoiesis of indeterminate potential (CHIP) are at increased risk of aging related health conditions and all-cause mortality, but whether CHIP impacts risk of infection is much less clear. Using UK Biobank data, we revealed a positive association between CHIP and incident pneumonia in 438,421 individuals. We show that inflammation enhanced pneumonia risk, as CHIP carriers with a hypomorphic IL6 receptor polymorphism were protected. To better characterize the pathways of susceptibility, we challenged hematopoietic Tet Methylcytosine Dioxygenase 2 knockout (Tet2–/–) and floxed control mice (Tet2f/f) with Streptococcus pneumoniae. As with human CHIP carriers, Tet2–/– mice had hematopoietic abnormalities resulting in the expansion of inflammatory monocytes and neutrophils in peripheral blood. Yet, these cells were insufficient in defending against S. pneumoniae and resulted in increased pathology, impaired bacterial clearance, and higher mortality in Tet2–/– mice. We delineated the transcriptional landscape of Tet2–/– neutrophils and found that while inflammation-related pathways were upregulated in Tet2–/– neutrophils, migration and motility pathways were compromised. Using live-imaging techniques, we demonstrated impairments in motility, pathogen uptake and neutrophil extracellular trap (NET) formation by Tet2–/– neutrophils. Collectively, we show that CHIP is a risk factor for bacterial pneumonia related to innate immune impairments.
Candice Quin, Erica N. DeJong, Elina K. Cook, Yi Zhen Luo, Caitlyn Vlasschaert, Sanathan Sadh, Amy J.M. McNaughton, Marco M. Buttigieg, Jessica A Breznik, Allison E. Kennedy, Kevin Zhao, Jeffrey Mewburn, Kimberly J. Dunham-Snary, Charles C.T. Hindmarch, Alexander G. Bick, Stephen L. Archer, Michael J. Rauh, Dawn M.E. Bowdish
BACKGROUND. The molecular signature of pediatric acute respiratory distress syndrome (ARDS) is poorly described, and the degree to which hyperinflammation or specific tissue injury contributes to outcomes is unknown. Therefore, we profiled inflammation and tissue injury dynamics over the first 7 days of ARDS, and associated specific biomarkers with mortality, persistent ARDS, and persistent multiple organ dysfunction syndrome (MODS). METHODS. In a single-center prospective cohort of intubated pediatric ARDS, we collected plasma on days 0, 3, and 7. Nineteen biomarkers reflecting inflammation, tissue injury, and damage associated molecular patterns were measured. We assessed the relationship between biomarkers and trajectories with mortality, persistent ARDS, or persistent MODS using multivariable mixed effect models. RESULTS. In 279 subjects (64 [23%] non-survivors), hyperinflammatory cytokines, tissue injury markers, and DAMPs were higher in non-survivors. Survivors and non-survivors showed different biomarker trajectories. IL-1α, sTNFR1, ANG2, and SPD increased in non-survivors, while DAMPs remained persistently elevated. ANG2 and P3NP were associated with persistent ARDS, whereas multiple cytokines, tissue injury markers, and DAMPs were associated with persistent MODS. Corticosteroid use did not impact the association of biomarker levels or trajectory with mortality. CONCLUSIONS. Pediatric ARDS survivors and non-survivors had distinct biomarker trajectories, with cytokines, endothelial and alveolar epithelial injury, and DAMPs elevated in non-survivors. Mortality markers overlapped with markers associated with persistent MODS, rather than persistent ARDS.
Nadir Yehya, Thomas J. Booth, Gnana D. Ardhanari, Jill M. Thompson, L.K. Metthew Lam, Jacob E. Till, Mark V. Mai, Garrett Keim, Daniel J. McKeone, E. Scott Halstead, Patrick Lahni, Brian M. Varisco, Wanding Zhou, Erica L. Carpenter, Jason D. Christie, Nilam S. Mangalmurti
Cancer-derived small extracellular vesicles (sEVs) are capable of modifying tumor microenvironment and promoting tumor progression. Ovarian cancer (OvCa) is a lethal malignancy that preferentially spreads through the abdominal cavity. Thus, the secretion of such vesicles into the peritoneal fluid could be a determinant factor in the dissemination and behavior of this disease. We designed a prospective observational study to assess the impact of peritoneal fluid-derived sEVs (PFD-sEVs) in OvCa clinical outcome. For this purpose, two patient cohorts were enrolled, including OvCa cases who underwent a diagnostic or cytoreductive surgery, and non-oncological patients as controls, who underwent abdominal surgery for benign gynecological conditions. PFD-sEVs systematic extraction from surgical samples enabled us to observe significant quantitative and qualitative differences associated with cancer diagnosis, disease stage and platinum chemosensitivity. Proteomic profiling of PFD-sEVs led to the identification of molecular pathways and proteins of interest and to the biological validation of S100A4 and STX5. In addition, unsupervised analysis of PFD-sEVs proteomic profiles in high-grade serous ovarian carcinomas (HGSOC) revealed two clusters with different outcomes in terms of overall survival. In conclusion, comprehensive characterization of the PFD-sEVs content provided a prognostic value with potential implications in HGSOC clinical management.
Miguel Quiralte, Arantzazu Barquín, Mónica Yagüe Fernández, Paloma Navarro, Tatiana P. Grazioso, Elena Sevillano, Juan F. Rodriguez Moreno, Alejandra Balarezo-Saldivar, Héctor Peinado, Elena Izquierdo, Carlos Millán, Irene López Carrasco, Mario Prieto, Rodrigo Madurga de Lacalle, Ismael Fernández-Miranda, Sergio Ruiz-Llorente, Jesús García-Donas
Nuclear factor kappa-B (NFκB) is activated in arrhythmogenic cardiomyopathy (ACM) patient-derived iPSC-cardiac myocytes under basal conditions and inhibition of NFκB signaling prevents disease in Dsg2mut/mut mice, a robust mouse model of ACM. Here, we used genetic approaches and single cell RNA sequencing to define the contributions of immune signaling in cardiac myocytes and macrophages in the natural progression of ACM using Dsg2mut/mut mice. We found that NFκB signaling in cardiac myocytes drives myocardial injury, contractile dysfunction, and arrhythmias in Dsg2mut/mut mice. NFκB signaling in cardiac myocytes mobilizes macrophages expressing C-C motif chemokine receptor-2 (CCR2+ cells) to affected areas within the heart, where they mediate myocardial injury and arrhythmias. Contractile dysfunction in Dsg2mut/mut mice is caused both by loss of heart muscle and negative inotropic effects of inflammation in viable muscle. Single nucleus RNA sequencing and cellular indexing of transcriptomes and epitomes (CITE-seq) studies revealed marked pro-inflammatory changes in gene expression and the cellular landscape in hearts of Dsg2mut/mut mice involving cardiac myocytes, fibroblasts and CCR2+ macrophages. Changes in gene expression in cardiac myocytes and fibroblasts in Dsg2mut/mut mice were dependent on CCR2+ macrophage recruitment to the heart. These results highlight complex mechanisms of immune injury and regulatory crosstalk between cardiac myocytes, inflammatory cells and fibroblasts in the pathogenesis of ACM.
Stephen P. Chelko, Vinay R. Penna, Morgan Engel, Emily A. Shiel, Ann M. Centner, Waleed Farra, Elisa N. Cannon, Maicon Landim-Vieira, Niccole Schaible, Kory Lavine, Jeffrey E. Saffitz
Mediator kinases CDK19 and CDK8, pleiotropic regulators of transcriptional reprogramming, are differentially regulated by androgen signaling but both kinases are upregulated in castration-resistant prostate cancer (CRPC). Genetic or pharmacological inhibition of CDK8 and CDK19 reverses the castration-resistant phenotype and restores the sensitivity of CRPC xenografts to androgen deprivation in vivo. Prolonged CDK8/19 inhibitor treatment combined with castration not only suppresses the growth of CRPC xenografts but also induces tumor regression and cures. Transcriptomic analysis revealed that Mediator kinase inhibition amplifies and modulates the effects of castration on gene expression, disrupting CRPC adaptation to androgen deprivation. Mediator kinase inactivation in tumor cells also affects stromal gene expression, indicating that Mediator kinase activity in CRPC molds the tumor microenvironment. The combination of castration and Mediator kinase inhibition downregulates the MYC pathway, and Mediator kinase inhibition suppresses a MYC-driven CRPC tumor model even without castration. CDK8/19 inhibitors show efficacy in patient-derived xenograft models of CRPC, and a gene signature of Mediator kinase activity correlates with tumor progression and overall survival in clinical samples of metastatic CRPC. These results indicate that Mediator kinases mediate androgen-independent in vivo growth of CRPC, supporting the development of CDK8/19 inhibitors for the treatment of this presently incurable disease.
Jing Li, Thomas A. Hilimire, Liu Yueying, Lili Wang, Jiaxin Liang, Balázs Győrffy, Vitali Sikirzhytski, Hao Ji, Li Zhang, Chen Cheng, Xiaokai Ding, Kendall R. Kerr, Charles E. Dowling, Alexander A. Chumanevich, Zachary T. Mack, Gary P. Schools, Chang-uk Lim, Leigh Ellis, Xiaolin Zi, Donald C. Porter, Eugenia V. Broude, Campbell McInnes, George Wilding, Michael B. Lilly, Igor B. Roninson, Mengqian Chen
Aberrant expression of ETS transcription factors characterizes numerous human malignancies. Many of these proteins, including EWS::FLI1 and EWS::ERG fusions in Ewing sarcoma (EwS) and TMPRSS2::ERG in prostate cancer (PCa), drive oncogenic programs via binding to GGAA repeats. We report here that both EWS::FLI1 and ERG bind and transcriptionally activate GGAA-rich pericentromeric heterochromatin. The respective pathogen-like HSAT2 and HSAT3 RNAs, together with LINE, SINE, ERV and other repeat transcripts, are expressed in EwS and PCa tumors, secreted in extracellular vesicles (EVs) and are highly elevated in plasma of EwS patients with metastatic disease. High HSAT2,3 levels in EWS::FLI1 or ERG expressing cells and tumors were associated with induction of G2/M checkpoint, mitotic spindle and DNA damage programs. These programs were also activated in EwS EV-treated fibroblasts, coincident with accumulation of HSAT2,3 RNAs, proinflammatory responses, mitotic defects, and senescence. Mechanistically, HSAT2,3-enriched cancer EVs induced cGAS-TBK1 innate immune signaling and formation of cytosolic granules positive for double-strand RNAs, RNA-DNA and cGAS. Hence, aberrantly expressed ETS proteins derepress pericentromeric heterochromatin, yielding pathogenic RNAs which transmit genotoxic stress and inflammation to local and distant sites. Monitoring HSAT2,3 plasma levels and preventing their dissemination may thus improve therapeutic strategies and blood-based diagnostics.
Peter Ruzanov, Valentina Evdokimova, Manideep C. Pachva, Alon Minkovich, Zhenbo Zhang, Sofya Langman, Hendrik Gassmann, Uwe Thiel, Marija Orlic-Milacic, Syed H. Zaidi, Vanya Peltekova, Lawrence E. Heisler, Manju Sharma, Michael E. Cox, Trevor D. McKee, Mark Zaidi, Eve Lapouble, John D. McPherson, Olivier Delattre, Laszlo Radvanyi, Stefan E.G. Burdach, Lincoln D. Stein, Poul H. Sorensen
G protein-coupled receptor 37-like 1 (GPR37L1) is an orphan GPCR with largely unknown functions. Here we report that Gpr37l1/GRP37L1 ranks among the most highly expressed GPCR transcripts in mouse and human dorsal root ganglia (DRGs), selectively expressed in satellite glial cells (SGCs). Peripheral neuropathy induced by streptozotoxin (STZ) and paclitaxel (PTX) led to reduced GPR37L1 expression on the plasma membrane expression in mouse and human DRGs. Transgenic mice with Gpr37l1 deficiency exhibited impaired resolution of neuropathic pain symptoms following PTX and STZ-induced pain, whereas overexpression of Gpr37l1 in mouse DRGs reversed pain. GPR37L1 is co-expressed with potassium channels, including KCNJ10 (Kir4.1) in mouse SGCs and both KCNJ3 (Kir3.1) and KCNJ10 in human SGCs. GPR37L1 regulates the surface expression and function of the potassium channels. Notably, the pro-resolving lipid mediator maresin 1 (MaR1) serves as a ligand of GPR37L1 and enhances KCNJ10 or KCNJ3-mediated potassium influx in SGCs through GPR37L1. Chemotherapy suppressed KCNJ10 expression and function in SGCs, which MaR1 rescued through GPR37L1. Finally, genetic analysis revealed that the GPR37L1-E296K variant increased chronic pain risk by destabilizing the protein and impairing the protein’s function. Thus, GPR37L1 in SGCs offers a new therapeutic target for the protection of neuropathy and chronic pain.
Sangsu Bang, Changyu Jiang, Jing Xu, Sharat Chandra, Aidan McGinnis, Xin Luo, Qianru He, Yize Li, Zilong Wang, Xiang Ao, Marc Parisien, Lorenna Oliveira Fernandes de Araujo, Sahel Jahangiri Esfahani, Qin Zhang, Raquel Tonello, Temugin Berta, Luda Diatchenko, Ru-Rong Ji
Gender affirming hormone therapy (GAHT) is often prescribed to transgender (TG) adolescents to alleviate gender dysphoria, but the impact of GAHT on the growing skeleton is unclear. We found GAHT to improve trabecular bone structure via increased bone formation in young male mice and not to affect trabecular structure in female mice. GAHT modified gut microbiome composition in both male and female mice. However, fecal microbiota transfers (FMT) revealed that GAHT-shaped gut microbiome was a communicable regulator of bone structure and turnover in male, but not in female mice. Mediation analysis identified two species of Bacteroides as significant contributors to the skeletal effects of GAHT in male mice, with Bacteroides supplementation phenocopying the effects of GAHT on bone. Bacteroides have the capacity to expand Treg populations in the gut. Accordingly, GAHT expanded intestinal regulatory T cells (Tregs) and stimulated their homing to the bone marrow (BM) in male but not in female mice. Attesting to the functional relevance of Tregs, pharmacological blockade of Treg expansion prevented GAHT-induced bone anabolism. In summary, in male mice GAHT stimulated bone formation and improved trabecular structure by promoting Treg expansion via a microbiome-mediated effect. In female mice GAHT neither improved nor impaired trabecular structure.
Subhashis Pal, Xochitl Morgan, Hamid Y. Dar, Camilo Anthony Gacasan, Sanchiti Patil, Andreea Stoica, Yi-Juan Hu, M. Neale Weitzmann, Rheinallt M. Jones, Roberto Pacifici
The mammalian SUMO-targeted E3 Ubiquitin Ligase, Rnf4, has been reported to act as a regulator of DNA repair, but the importance of RNF4 as a tumor suppressor has not been tested. Using a conditional-knockout mouse model, we deleted Rnf4 in the B cell lineage to test the importance of RNF4 for growth of somatic cells. Although Rnf4 conditional-knockout B cells exhibited substantial genomic instability, Rnf4 deletion caused no increase in tumor susceptibility. In contrast, Rnf4 deletion extended the healthy lifespan of mice expressing an oncogenic c-myc transgene. Rnf4 activity is essential for normal DNA replication, and in its absence, there was a failure in ATR-CHK1 signaling of replication stress. Factors that normally mediate replication fork stability, including members of the Fanconi Anemia gene family and the helicases, PIF1 and RECQL5, showed reduced accumulation at replication forks in the absence of RNF4. RNF4 deficiency also resulted in an accumulation of hyper-SUMOylated proteins in chromatin, including members of the SMC5/6 complex, which contributes to replication failure by a mechanism dependent on RAD51. These findings indicate that RNF4, which shows increased expression in multiple human tumor types, is a potential target for anti-cancer therapy, especially in tumors expressing c-myc.
Joonyoung Her, Haiyan Zheng, Samuel F. Bunting
Despite widespread utilization of immunotherapy, challenge to treat immune-cold tumors needs to be resolved. Multiomic analyses and experimental validation identified the OTUD4-CD73 proteolytic axis as a promising target in treating immune-suppressive triple negative breast cancer (TNBC). Mechanistically, deubiquitylation of CD73 by OTUD4 counteracted its ubiquitylation by TRIM21, resulting in CD73 stabilization that inhibits tumor immune responses. We further demonstrated the importance of TGF-β signaling for orchestrating the OTUD4-CD73 proteolytic axis within tumor cells. Spatial transcriptomics profiling discovered spatially resolved features of interacting malignant and immune cells pertaining to expression levels of OTUD4 and CD73. In addition, ST80, a newly developed inhibitor, specifically disrupted proteolytic interaction between CD73 and OTUD4, leading to reinvigoration of cytotoxic CD8+ T cell activities. In preclinical models of TNBC, ST80 treatment sensitized refractory tumors to anti-PD-L1 therapy. Collectively, our findings uncover a novel strategy for targeting immunosuppressive OTUD4-CD73 proteolytic axis in treating immune-suppressive breast cancers with the inhibitor ST80.
Yueming Zhu, Anupam Banerjee, Ping Xie, Andrey A. Ivanov, Amad Uddin, Qiao Jiao, Junlong J. Chi, Lidan Zeng, Ji Young Lee, Yifan Xue, Xinghua Lu, Massimo Cristofanilli, William J. Gradishar, Curtis J. Henry, Theresa W. Gillespie, Manali Ajay Bhave, Kevin Kalinsky, Haian Fu, Ivet Bahar, Bin Zhang, Yong Wan
Antibodies can initiate lung injury in a variety of disease states such as autoimmunity, transfusion reactions, or after organ transplantation, but the key factors determining in vivo pathogenicity of injury-inducing antibodies are unclear. Harmful antibodies often activate the complement cascade. A model for how IgG antibodies trigger complement activation involves interactions between IgG Fc domains driving assembly of IgG hexamer structures that activate C1 complexes. The importance of IgG hexamers in initiating injury responses was unclear, so we tested their relevance in a mouse model of alloantibody and complement-mediated acute lung injury. We used three approaches to block alloantibody hexamerization (antibody carbamylation, the K439E Fc mutation, or treatment with domain B from Staphylococcal protein A), all of which reduced acute lung injury. Conversely, Fc mutations promoting spontaneous hexamerization made a harmful alloantibody into a more potent inducer of acute lung injury and rendered an innocuous alloantibody pathogenic. Treatment with a recombinant Fc hexamer ‘decoy’ therapeutic protected mice from lung injury, including in a model with transgenic human FCGR2A expression that exacerbated pathology. These results indicate an in vivo role of IgG hexamerization in initiating acute lung injury and the potential for therapeutics that inhibit or mimic hexamerization to treat antibody-mediated diseases.
Simon J. Cleary, Yurim Seo, Jennifer J. Tian, Nicholas Kwaan, David P. Bulkley, Arthur E. H. Bentlage, Gestur Vidarsson, Éric Boilard, Rolf Spirig, James C. Zimring, Mark R. Looney
Lactylation has been recently identified as a new type of posttranslational modification widely occurring on lysine residues of both histone and non-histone proteins. The acetyl transferase p300 is thought to mediate protein lactylation, yet the cellular concentration of the proposed lactyl-donor, lactyl-coenzyme A is about 1,000 times lower than that of acetyl-CoA, raising the question whether p300 is a genuine lactyl-transferase. Here, we report the Alanyl-tRNA synthetase 1 (AARS1) moonlights as a bona fide lactyl-transferase that directly uses lactate and ATP to catalyze protein lactylation. Among the candidate substrates, we focused on the Hippo pathway that has a well-established role in tumorigenesis. Specifically, AARS1 was found to sense intracellular lactate and translocate into the nucleus to lactylate and activate YAP-TEAD complex; and AARS1 itself was identified as a Hippo target gene that forms a positive feedback loop with YAP-TEAD to promote gastric cancer (GC) cell proliferation. Consistently, the expression of AARS1 was found to be upregulated in GC, and elevated AARS1 expression was found to be associated with poor prognosis for GC patients. Collectively, this work discovered AARS1 with lactyl-transferase activity in vitro and in vivo and revealed how the metabolite lactate is translated into a signal of cell proliferation.
Junyi Ju, Hui Zhang, Moubin Lin, Zifeng Yan, Liwei An, Zhifa Cao, Dandan Geng, Jingwu Yue, Yang Tang, Luyang Tian, Fan Chen, Yi Han, Wenjia Wang, Shimin Zhao, Jiao Shi, Zhaocai Zhou
Elevated bone resorption and diminished bone formation have been recognized as the primary features of glucocorticoid-associated skeletal disorders. However, the direct effects of excess glucocorticoids on bone turnover remains unclear. Here, we explored the outcomes of exogenous glucocorticoid treatment on bone loss and delayed fracture healing in mice and found that reduced bone turnover was a dominant feature, resulting in a net loss of bone mass. The primary effect of glucocorticoids on osteogenic differentiation was not inhibitory; instead, they cooperated with macrophages to facilitate osteogenesis. Impaired local nutrient status, notably, obstructed fatty acid transportation, was a key factor contributing to glucocorticoid-induced impairment of bone turnover in vivo. Furthermore, fatty acid oxidation in macrophages fueled the ability of glucocorticoid-liganded receptors to enter the nucleus and then promoted the expression of Bmp2, a key cytokine that facilitates osteogenesis. Metabolic reprogramming by localized fatty acid delivery partly rescued glucocorticoid-induced pathology by restoring a healthier immune-metabolic milieu. These data provide insights into the multifactorial metabolic mechanisms by which glucocorticoids generate skeletal disorders, thus suggesting possible therapeutic avenues.
Xu Li, Tongzhou Liang, Bingyang Dai, Liang Chang, Yuan Zhang, Shiwen Hu, Jiaxin Guo, Shunxiang Xu, Lizhen Zheng, Hao Yao, Hong Lian, Yu Nie, Ye Li, Xuan He, Zhi Yao, Wenxue Tong, Xinluan Wang, Dick Ho Kiu Chow, Jiankun Xu, Ling Qin
Fibrosis following tissue injury is distinguished from normal repair by the accumulation of pathogenic and apoptosis-resistant myofibroblasts (MFs), which arise primarily by differentiation from resident fibroblasts. Endogenous molecular brakes that promote MF dedifferentiation and clearance during spontaneous resolution of experimental lung fibrosis may provide insights that could inform and improve treatment of progressive pulmonary fibrosis in patients. Mitogen-activated protein kinase (MAPK) phosphatase-1 (MKP1) influences cellular phenotype and fate through precise and timely regulation of MAPK activity within various cell types and tissues, yet its role in lung fibroblasts and pulmonary fibrosis has not been explored. Utilizing gain- and loss-of-function studies, we found that MKP1 promoted lung MF dedifferentiation and restored their sensitivity to apoptosis — effects determined to be mainly dependent upon its dephosphorylation of p38α MAPK (p38α). Fibroblast-specific deletion of MKP1 following peak bleomycin-induced lung fibrosis largely abrogated its subsequent spontaneous resolution. Such resolution was restored by treating these transgenic mice with the p38α inhibitor VX-702. We conclude that MKP1 is a critical antifibrotic brake whose inhibition of pathogenic p38α in lung fibroblasts is necessary for fibrosis resolution following lung injury.
Sean M. Fortier, Natalie M. Walker, Loka R. Penke, Jared D. Baas, Qinxue Shen, Jennifer M. Speth, Steven K. Huang, Rachel L. Zemans, Anton M. Bennett, Marc Peters-Golden
Bacterial translocation from the gut microbiota is a source of sepsis in susceptible patients. Previous work suggests that overgrowth of gut pathobionts, including Klebsiella pneumoniae, increases the risk of disseminated infection. Our data from a human dietary intervention study found that in the absence of fiber, K. pneumoniae bloomed during microbiota recovery from antibiotic treatment. We thus hypothesized that dietary nutrients directly support or suppress colonization of this gut pathobiont in the microbiota. Consistent with our human subject study, complex carbohydrates in dietary fiber suppressed colonization of K. pneumoniae and allowed for recovery of competing commensals in mouse modeling. In contrast, through ex-vivo and in vivo modeling, we identify simple carbohydrates as a limiting resource for K. pneumoniae in the gut. As proof of principle, supplementation with lactulose, a non-absorbed simple carbohydrate and an FDA approved therapy, increased colonization of K. pneumoniae. Disruption of the intestinal epithelium led to dissemination of K. pneumoniae into the bloodstream and liver, which was prevented by dietary fiber. Our results show that dietary simple and complex carbohydrates are critical not only in the regulation of pathobiont colonization but also disseminated infection, suggesting that targeted dietary interventions may offer a preventative strategy in high-risk patients.
Aaron L. Hecht, Lisa C. Harling, Elliot S. Friedman, Ceylan Tanes, Junhee Lee, Jenni Firrman, Fuhua Hao, Vincent Tu, LinShu Liu, Andrew D. Patterson, Kyle Bittinger, Mark Goulian, Gary D. Wu
Yukun Guan, Brandon Peiffer, Dechun Feng, Maria A. Parra, Yang Wang, Yaojie Fu, Vijay H. Shah, Andrew M. Cameron, Zhaoli Sun, Bin Gao
Clarkson disease (monoclonal gammopathy-associated idiopathic systemic capillary leak syndrome, ISCLS) is a rare, relapsing-remitting disorder featuring the abrupt extravasation of fluids and proteins into peripheral tissues, which in turn leads to hypotensive shock, severe hemoconcentration, and hypoalbuminemia. Specific leakage factor(s) and pathways in ISCLS are unknown, and there is no effective treatment for acute flares. Here we characterize an autonomous vascular endothelial defect in ISCLS that is recapitulated in patient-derived endothelial cells (ECs) in culture and in a mouse model of disease. ISCLS-derived ECs are functionally hyper-responsive to permeability-inducing factors like VEGF and histamine in part due to increased endothelial nitric oxide synthase (eNOS) activity. eNOS blockade by administration of N(γ)-nitro-L-arginine methyl ester (L-NAME) ameliorates vascular leakage in an SJL/J mouse model of ISCLS induced by histamine or VEGF challenge. eNOS mislocalization and decreased protein phosphatase 2A (PP2A) expression may contribute to eNOS hyper-activation in ISCLS-derived ECs. Our findings provide mechanistic insights into microvascular barrier dysfunction in ISCLS and highlight a potential therapeutic approach.
Ararat J. Ablooglu, Wei-Sheng Chen, Zhihui Xie, Abhishek Desai, Subrata Paul, Justin B. Lack, Linda A. Scott, A. Robin Eisch, Arkadiusz Z. Dudek, Samir M. Parikh, Kirk M. Druey
Chimeric antigen receptor (CAR) designs that incorporate pharmacologic control are desirable, however designs suitable for clinical translation are needed. We designed a fully human, rapamycin-regulated, drug product for targeting CD33+ tumors called dimerization agent regulated immunoreceptor complex (DARIC33). T cell products demonstrated target specific and rapamycin-dependent cytokine release, transcriptional responses, cytotoxicity, and in vivo antileukemic activity in the presence of as little as 1nM rapamycin. Rapamycin withdrawal paused DARIC33-stimulated T cell effector functions, which were restored following re-exposure to rapamycin, demonstrating reversible effector function control. While rapamycin-regulated DARIC33 T cells were highly sensitive to target antigen, CD34+ stem cell colony forming capacity was not impacted. We benchmarked DARIC33 potency relative to CD19 CAR T cells to estimate a T cell dose for clinical testing. In addition, we integrated in vitro and preclinical in vivo drug concentration thresholds for OFF-ON state transitions, as well as murine and human rapamycin pharmacokinetics, to estimate a clinically applicable rapamycin dosing schedule. A phase 1 DARIC33 trial has been initiated (PLAT-08, NCT05105152), with initial evidence of rapamycin-regulated T cell activation and anti-tumor impact. Our findings provide evidence that the DARIC platform exhibits sensitive regulation and potency needed for clinical application to other important immunotherapy targets.
Jacob Appelbaum, April E. Price, Kaori Oda, Joy Zhang, Wai-Hang Leung, Giacomo Tampella, Dong Xia, Pauline P.L. So, Sarah K. Hilton, Claudya Evandy, Semanti Sarkar, Unja Martin, Anne-Rachel Krostag, Marissa Leonardi, Daniel E. Zak, Rachael Logan, Paula Lewis, Secil Franke-Welch, Njabulo Ngwenyama, Michael Fitzgerald, Niklas Tulberg, Stephanie Rawlings-Rhea, Rebecca A. Gardner, Kyle Jones, Angelica Sanabria, William Crago, John Timmer, Andrew Hollands, Brendan Eckelman, Sanela Bilic, Jim Woodworth, Adam Lamble, Philip D. Gregory, Jordan Jarjour, Mark Pogson, Joshua A. Gustafson, Alexander Astrakhan, Michael C. Jensen