Approximately 80% of pancreatic cancer patients suffer from cachexia and one-third die due to cachexia-related complications such as respiratory failure and cardiac arrest. Although there has been considerable research into cachexia mechanisms and interventions, there are, to date, no FDA-approved therapies. A major contributing factor could be the failure of animal models to accurately recapitulate the human condition. In this study, we generated an aged model of pancreatic cancer cachexia to compare cachexia progression in young versus aged tumor-bearing mice. Comparative skeletal muscle transcriptome analyses identified 3-methyladenine (3-MA) as a candidate anti-wasting compound. In vitro analyses confirmed anti-wasting capacity while in vivo analysis revealed potent anti-tumor effects. Transcriptome analyses of 3-MA-treated tumor cells implicated Perp as a 3-MA target gene. We subsequently 1) observed significantly higher expression of Perp in cancer cell lines compared to control cells, 2) noted a survival disadvantage associated with elevated Perp, and 3) found that 3-MA-associated Perp reduction inhibited tumor cell growth. Finally, we provide in vivo evidence that survival benefits conferred by 3-MA administration are independent of its effect on tumor progression. Taken together, we report a novel mechanism linking 3-MA to Perp inhibition, and further implicate PERP as a novel tumor promoting factor in pancreatic cancer.
Aneesha Dasgupta, Paige C. Arneson-Wissink, Rebecca E. Schmitt, Dong Seong Cho, Alexandra M. Ducharme, Tara L. Hogenson, Eugene W. Krueger, William R. Bamlet, Lizhi Zhang, Gina L. Razidlo, Martin E. Fernandez-Zapico, Jason D. Doles
BACKGROUND. >1,500 variants in the ABCA4 locus underlie a heterogeneous spectrum of retinal disorders ranging from aggressive childhood-onset chorioretinopathy to milder, late-onset macular disease. Genotype-phenotype correlation studies have been limited in clinical applicability as patient cohorts are typically small and seldom capture the full natural history of individual genotypes. To overcome these limitations, we constructed a genotype-phenotype correlation matrix that provides quantifiable probabilities of long-term disease outcomes associated with specific ABCA4 genotypes from a large, age-restricted patient cohort. METHODS. The study included 112 unrelated patients ≥50 years of age in whom 2 pathogenic variants were identified after sequencing of the ABCA4 locus. Clinical characterization was performed using the results of best-corrected visual acuity, retinal imaging and full-field electroretinogram testing. RESULTS. Four distinct prognostic groups were defined according to the spatial severity of disease features across the fundus. Recurring genotypes were observed in milder prognoses including those associated with a newly defined class of rare hypomorphic alleles. PVS1 (predicted null) variants were enriched in the most severe prognoses; however, missense variants comprised a larger than expected fraction of these patients. Analysis of allele combinations and their respective prognostic severity, showed that certain variants such as p.(Gly1961Glu), and both rare and frequent hypomorphic alleles, are “clinically dominant” with respect to patient phenotypes irrespective of the allele in trans. CONCLUSION. These results provide much needed structure to the complex genetic and clinical landscape of ABCA4 disease and adds a tool to the clinical repertoire to quantitatively assess individual genotype-specific prognoses in patients.
Winston Lee, Jana Zernant, Pei-Yin Su, Takayuki Nagasaki, Stephen H. Tsang, Rando Allikmets
Nonphlogistic migration of macrophages contributes to the clearance of pathogens and apoptotic cells: critical steps for the resolution of inflammation and return to homeostasis. Angiotensin-(1-7) [Ang-(1-7)] is an heptapeptide of the Renin-Angiotensin system that acts through Mas receptor (MasR). Ang-(1-7) has recently emerged as a novel pro-resolving mediator, yet Ang-(1-7) resolution mechanisms are not fully determined. Herein, Ang-(1-7) stimulated migration of human and murine monocytes/macrophages in a MasR, CCR2 and MEK/ERK1/2-dependent manner. Pleural injection of Ang-(1-7) promoted nonphlogistic mononuclear cell influx alongside increased levels of CCL2, IL-10 and macrophage polarization towards a regulatory phenotype. Ang-(1-7) induction of CCL2 and mononuclear cell migration was also dependent on MasR and MEK/ERK. Noteworthy, MasR was upregulated during resolution phase of inflammation and their pharmacological inhibition or genetic deficiency impaired mononuclear cell recruitment during self-resolving models of LPS pleurisy and E. coli peritonitis. Inhibition/absence of MasR was associated with reduced CCL2 levels, impaired phagocytosis of bacteria, efferocytosis and delayed resolution of inflammation. In summary, we have uncovered a novel pro-resolving feature of Ang-(1-7), namely the recruitment of mononuclear cells favoring efferocytosis, phagocytosis and resolution of inflammation. Mechanistically, cell migration was dependent on MasR, CCR2 and the MEK/ERK pathway.
Isabella Zaidan, Luciana P. Tavares, Michelle A. Sugimoto, Kátia M. Lima, Graziele L. Negreiros-Lima, Lívia C.R. Teixeira, Thais C. Miranda, Bruno V.S. Valiate, Allysson Cramer, Juliana Priscila Vago, Gabriel H. Campolina-Silva, Jéssica A.M. Souza, Laís C. Grossi, Vanessa Pinho, Maria Jose Campagnole-Santos, Robson A .S. Santos, Mauro M. Teixeira, Izabela Galvão, Lirlândia P. Sousa
Immune checkpoint therapy targeting the PD-1/PD-L1 axis is a novel development in anticancer therapy and has been applied to clinical medicine. However, there are still some problems, including a relatively low response rate, innate mechanisms of resistance against immune checkpoint blockades, and the absence of reliable biomarkers to predict responsiveness. In this study of in vitro and in vivo models, we demonstrate that PD-L1-vInt4, a splicing variant of PD-L1, plays a role as a decoy in anti-PD-L1 antibody treatment. First, we showed that PD-L1-vInt4 was detectable in clinical samples and that it was possible to visualize the secreting variants with IHC. By overexpressing the PD-L1-secreted splicing variant on MC38 cells, we observed that an immune-suppressing effect was not induced by their secretion alone. We then demonstrated that PD-L1-vInt4 secretion resisted anti-PD-L1 antibody treatment, compared with wild type PD-L1, which was explicable by the PD-L1-vInt4’s decoying of the anti-PD-L1 antibody. The decoying function of PD-L1 splicing variants may be one of the reasons for cancers being resistant to anti-PD-L1 therapy. Measuring serum PD-L1 levels might be helpful in deciding the therapeutic strategy.
Ray Sagawa, Seiji Sakata, Bo Gong, Yosuke Seto, Ai Takemoto, Satoshi Takagi, Hironori Ninomiya, Noriko Yanagitani, Masayuki Nakao, Mingyon Mun, Ken Uchibori, Makoto Nishio, Yasunari Miyazaki, Yuichi Shiraishi, Seishi Ogawa, Keisuke Kataoka, Naoya Fujita, Kengo Takeuchi, Ryohei Katayama
Accumulating evidence has shown that cancer stroma and bone marrow-derived cells (BMDCs) in the tumor microenvironment (TME) play vital roles in tumor progression. However, the mechanism by which oral cancer stroma recruits any particular subset of BMDCs remains largely unknown. Here we sought to identify the subset of BMDCs that is recruited by cancer stroma. We established a sequential transplantation model in BALB/c nude mice, including (i) bone marrow transplantation of GFP-expressing cells and (ii) co-xenografting of patient-derived stroma (two cases, designated PDS1 and PDS2) with oral cancer cells (HSC-2). As controls, xenografting was performed with HSC-2 alone or in combination with normal human dermal fibroblasts (HDF). PDS1, PDS2, and HDF all promoted BMDCs migration in vitro and recruitment in vivo. Multicolor immunofluorescence revealed that the PDS co-xenografts recruited Arginase-1/CD11b/GR1/GFP quadruple-positive cells, which are myeloid-derived suppressor cells (MDSCs), to the TME, whereas the HDF co-xenograft did not. Screening using microarrays revealed that PDS1 and PDS2 expressed CCL2 mRNA (encoding C-C motif chemokine ligand 2) at higher levels than did HDF. Indeed, PDS xenografts contained significantly higher proportions of CCL2-positive stromal cells and CCR2/Arginase-1/CD11b/GR1 quadruple-positive MDSCs (as receiver cells) than the HDF co-xenograft. Consistently, a CCL2 synthesis inhibitor and a CCR2 antagonist significantly inhibited the PDS-driven migration of BM cells in vitro. Furthermore, intraperitoneal injection of the CCR2 antagonist to the PDS xenograft models significantly reduced the CCR2/Arginase-1/CD11b/GR1 quadruple-positive MDSCs infiltration to the TME. In conclusion, oral cancer stroma-secreted CCL2 is a key signal for recruiting CCR2-positive MDSCs from bone marrow to the TME.
May Wathone Oo, Hotaka Kawai, Kiyofumi Takabatake, Shuta Tomida, Takanori Eguchi, Kisho Ono, Qiusheng Shan, Toshiaki Ohara, Saori Yoshida, Haruka Omori, Shintaro Sukegawa, Keisuke Nakano, Kuniaki Okamoto, Akira Sasaki, Hitoshi Nagatsuka
A fibrotic stroma accumulates in advanced cancers, and invasive cancer cells migrate along collagen fibers that facilitate dissemination from the primary tumor. However, the ways in which tumor cells govern these processes remain unclear. Here, we report that the epithelial-to-mesenchymal transition–activating transcription factor ZEB1 increased type I collagen (Col1) secretion and enhanced tumor cell adherence to type 1 collagen (Col1). Mechanistically, ZEB1 increased the levels of α1β1 integrin (encoded by Itga1 and Itgb1) by inhibiting PP2A activity, which reduced nuclear accumulation of HDAC4 and thereby derepressed Itga1 gene transcription. In parallel, ZEB1 relieved Itga1 from microRNA-148a-mediated silencing. High levels of Itga1 enhanced tumor cell adherence to Col1 and were essential for Col1-induced tumor growth and metastasis. Furthermore, ZEB1 enhanced Col1 secretion by increasing the expression of a kinesin protein that facilitated transport and secretion of Col1-containing vesicles. Our findings elucidate a transcriptional mechanism by which lung adenocarcinoma cells coordinate a collagen deposition and adhesion process that facilitates tumor progression.
Xiaochao Tan, Priyam Banerjee, Xin Liu, Jiang Yu, Sieun Lee, Young-Ho Ahn, Chad J. Creighton, Jonathan M. Kurie
Acute Respiratory Distress Syndrome (ARDS) is a common cause of respiratory failure yet has few pharmacologic therapies, reflecting the mechanistic heterogeneity of lung injury. We hypothesized that damage to the alveolar epithelial glycocalyx, a layer of glycosaminoglycans interposed between the epithelium and surfactant, contributes to lung injury in ARDS patients. Using mass spectrometry of airspace fluid noninvasively collected from mechanically-ventilated patients, we found that airspace glycosaminoglycan shedding (an index of glycocalyx degradation) occurred predominantly in patients with direct lung injury and was associated with duration of mechanical ventilation. Male patients had increased shedding which correlated with airspace concentrations of matrix metalloproteinases. Selective epithelial glycocalyx degradation in mice was sufficient to induce surfactant dysfunction, a key characteristic of ARDS, leading to microatelectasis and decreased lung compliance. Rapid colorimetric quantification of airspace glycosaminoglycans was feasible and could provide point-of-care prognostic information to clinicians and/or be used for predictive enrichment in clinical trials.
Alicia N. Rizzo, Sarah M. Haeger, Kaori Oshima, Yimu Yang, Alison M. Wallbank, Ying Jin, Marie Lettau, Lynda A. McCaig, Nancy E. Wickersham, J. Brennan McNeil, Igor Zakharevich, Sarah A. McMurtry, Christophe J. Langouët-Astrié, Katrina W. Kopf, Dennis R. Voelker, Kirk C. Hansen, Ciara M. Shaver, V. Eric Kerchberger, Ryan A. Peterson, Wolfgang M. Kuebler, Matthias Ochs, Ruud A.W. Veldhuizen, Bradford J. Smith, Lorraine B. Ware, Julie A. Bastarache, Eric P. Schmidt
The protein tau and its isoforms are associated with several neurodegenerative diseases, many of which are characterized by greater deposition of the 4R tau isoform; however, the role of 4R tau in disease pathogenesis remains unclear. We created antisense oligonucleotides (ASOs) that alter the ratio of 3R:4R tau to investigate the role of specific tau isoforms in disease. Preferential expression of 4R tau in human tau (hTau)-expressing mice was previously shown to increase seizure severity and phosphorylated tau deposition without neuronal or synaptic loss. In this study, we observed strong colocalization of 4R tau within reactive astrocytes and increased expression of pan-reactive and neurotoxic genes following 3R to 4R tau splicing ASO treatment in hTau mice. Increasing 4R tau levels in primary astrocytes provoked a similar response, including a neurotoxic genetic profile and diminished homeostatic function, which was replicated in human iPSC-derived astrocytes harboring a mutation that exhibits greater 4R tau. Healthy neurons cultured with 4R tau-expressing human iPSC-derived astrocytes exhibited a higher firing frequency and hyper-synchrony, which could be prevented by lowering tau expression. These findings support a novel pathway by which astrocytic 4R tau mediates reactivity and dysfunction and suggest that astrocyte-targeted therapeutics against 4R tau may mitigate neurodegenerative disease progression.
Lubov A. Ezerskiy, Kathleen M. Schoch, Chihiro Sato, Mariana Beltcheva, Kanta Horie, Frank Rigo, Ryan Martynowicz, Celeste M. Karch, Randall J. Bateman, Timothy M. Miller
Isolation guidelines for severe acute respiratory syndrome–cornavirus-2 (SARS-CoV-2) are largely derived from data collected prior to emergence of the delta variant. We followed a cohort of ambulatory patients with post-vaccination breakthrough SARS-CoV-2 infections with longitudinal collection of nasal swabs for SARS-CoV-2 viral load quantification, whole genome sequencing, and viral culture. All delta variant infections (10/10, 100%) in our cohort were symptomatic, compared with 64% (9/14) of non-delta variant infections. Symptomatic delta variant breakthrough infections were characterized by higher initial viral load, longer duration of virologic shedding by PCR, greater likelihood of replication-competent virus at early stages of infection, and longer duration of culturable virus compared to non-delta variants. The duration of time since vaccination was also correlated with both duration of PCR positivity and duration of detection of replication-competent virus. Nonetheless, no individuals with symptomatic delta variant infections had replication-competent virus by day 10 after symptom onset or 24 hours after resolution of symptoms. These data support current US Center for Disease Control isolation guidelines and reinforce the importance of prompt testing and isolation among symptomatic individuals with delta variant breakthrough infections. Additional data are needed to evaluate these relationships among asymptomatic and more severe delta variant breakthrough infections.
Mark J. Siedner, Julie Boucau, Rebecca F. Gilbert, Rockib Uddin, Jonathan Luu, Sebastien Haneuse, Tammy Vyas, Zahra Reynolds, Surabhi Iyer, Grace C. Chamberlin, Robert H. Goldstein, Crystal M. North, Chana A. Sacks, James Regan, James P. Flynn, Manish C. Choudhary, Jatin M. Vyas, Amy K. Barczak, Jacob E. Lemieux, Jonathan Z. Li
BACKGROUND. While most children experience mild COVID-19, high-risk children with underlying conditions may develop severe disease, requiring interventions. Kinetics of antibodies transferred via COVID-19 convalescent plasma early in disease, have not been characterized. METHODS. In this study (NCT04377672), high-risk children were prospectively enrolled to receive high-titer COVID-19 convalescent plasma (>1:320 anti-spike IgG; Euroimmun). Passive transfer of antibodies and endogenous antibody production were serially evaluated for up to 2 months after transfusion. Commercial and research ELISA assays, virus neutralization assays, high-throughput phage-display assay utilizing a coronavirus epitope library and pharmacokinetic analyses were performed. RESULTS. Fourteen high-risk children (median age 7.5 years) received high-titer COVID-19 convalescent plasma, nine children within five days (range 2-7) of symptom onset and five children within 4 days (range 3-5) after exposure to SARS-CoV-2. There were no serious adverse events related to transfusion. Antibodies to SARS-CoV-2 were transferred from the donor to the recipient, but antibody titers declined by 14-21 days with a 15.1-day t½ for spike protein IgG. Donor plasma had significant neutralization capacity which was transferred to the recipient. However, as early as 30 minutes post-transfusion, recipient plasma had low neutralization capacity. CONCLUSIONS. Convalescent plasma transfused to high-risk children appears to be safe with expected antibody kinetics, regardless of weight or age. However, current use of convalescent plasma in high-risk children achieves low neutralizing capacity.
Oren Gordon, Mary Katherine Brosnan, Steve Yoon, Dawoon Jung, Kirsten Littlefield, Abhinaya Ganesan, Christopher A. Caputo, Maggie Li, William R. Morgenlander, Stephanie N. Henson, Alvaro A. Ordonez, Patricia De Jesus, Elizabeth W. Tucker, Nadine Peart Akindele, Zexu Ma, Jo Wilson, Camilo A. Ruiz-Bedoya, M. Elizabeth M. Younger, Evan M. Bloch, Shmuel Shoham, David Sullivan, Aaron A.R. Tobian, Kenneth R. Cooke, Ben Larman, Jogarao V.S. Gobburu, Arturo Casadevall, Andrew Pekosz, Howard M. Lederman, Sabra L. Klein, Sanjay K. Jain
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