Issue published December 16, 2024 Previous issue
- Volume 134, Issue 24
Go to section:
On the cover: DAG promotes acquired resistance in targeted therapeutics
Wang et al. reveal that the accumulation of diacylglycerol (DAG; yellow) drives resistance to BRAF/EGFR therapies (red) in BRAFV600E-mutant metastatic colorectal cancer. Intracellular DAG buildup activates alternative signaling pathways, enabling adaptive resistance. The cover art depicts the metabolic flexibility of cancer cells in response to pharmacological challenge. Image credit: Jiawei Wang.
-
Commentaries
×
Abstract
The approach and efficacy of treatments for high-grade serous carcinoma (HGSC) of the ovary have changed little in decades. Although numerous studies demonstrated immune infiltration as frequent and prognostically beneficial, clinical trials of immunotherapies have generated benefit in fewer than 15% of patients. In this issue of the JCI, Nelson and colleagues compiled 1,233 HGSC samples from patients across four continents and compared the molecular and immunologic features that associate with long-term survival (greater than 10 years). Diversity among HGSC tumors is well defined, but this study explored the combined influence of immunologic and molecular features. Long-term survivors harbored tumors with high epithelial content and overrepresentation of the C4/differentiated molecular signature, with cytotoxic T and B cells infiltrating to the tumor epithelium and stroma, respectively. These findings highlight features that might underly poor responsiveness to existing immunotherapies of most HGSC tumors and considerations for the design of future, more precise treatments for HGSC.
Authors
Jeanette E. Boudreau
×Abstract
Aging negatively affects the capacity of muscle stem cells (MuSCs) to regenerate muscle. In this issue of the JCI, Ancel, Michaud, and colleagues used a high-content imaging screen to identify nicotinamide and pyridoxine as promoters of MuSC function. The combination of the two compounds promoted MuSC function in vivo in aged mice and in primary cells isolated from older individuals. Furthermore, the two compounds were lower in the circulation of older men, paralleling decreases in lean mass and gait speed. These results advance the translational perspective of rejuvenating MuSC function through nutraceuticals.
Authors
Taylor Peach, Mattia Quattrocelli
×Abstract
Despite many attempts, there is currently no approved vaccine to prevent Staphylococcus aureus infections. Preclinical vaccination models have failed to predict vaccine efficacy in humans as S. aureus exposure in humans imprints an immune response that is lacking in naive animals. In this issue of the JCI, Tsai and colleagues identify the cytokine IL-10 as the driver of humoral imprinting by S. aureus. Upon vaccination, S. aureus–experienced animals produced copious levels of IL-10, resulting in the hyper-α2,3 sialylation of antibodies, which interfered with the phagocytic-promoting properties of the vaccine-elicited anti–S. aureus antibodies. These findings correlate with the observation that hyperproduction of IL-10 in humans also induces hyper-α2,3 sialylation of antibodies and provide a possible mechanism for previous vaccine failures.
Authors
Victor J. Torres
×Abstract
Following respiratory infection or injury, neutrophil hyperactivation can damage surrounding lung tissue by releasing harmful compounds. In this issue of the JCI, Moussavi-Harami and colleagues identified tyrosine phosphatase SHP1 as a key negative regulator of neutrophil activation in acute respiratory distress syndrome (ARDS). Neutrophil-specific Shp1 disruption leads to hyperinflammation, pulmonary hemorrhage, and increased mortality in both sterile and pathogen-induced acute lung injury (ALI). Large intravascular neutrophil clusters and excessive PAD4-independent neutrophil extracellular traps (NETs) were identified as key features of lung injury. Mechanistically, Shp1 deficiency resulted in uncontrolled SYK kinase activation, driving chaotic neutrophil hyperactivation and inflammation.
Authors
Laxman Ghimire, Hongbo R. Luo
×Abstract
Despite the impressive clinical benefits and widespread adoption of sodium glucose cotransporter 2 inhibitors (SGLT2i) to treat all classes of heart failure, their cardiovascular mechanisms of action are poorly understood. Proposed mechanisms range broadly and include enhanced ketogenesis, where the mild ketosis associated with SGLT2i use is presumed to be beneficial. However, in this issue of the JCI, carefully conducted metabolic flux studies by Goedeke et al. comparing the effects of SGLT2i and exogenous ketones suggest differential effects. Thus, the mechanisms of action for SGLT2i are likely pleiotropic, and further work is needed to fully understand their beneficial effects.
Authors
Justin H. Berger, Brian N. Finck
-
Research Articles
×
Abstract
Skeletal muscle relies on resident muscle stem cells (MuSCs) for growth and repair. Aging and muscle diseases impair MuSC function, leading to stem cell exhaustion and regenerative decline that contribute to the progressive loss of skeletal muscle mass and strength. In the absence of clinically available nutritional solutions specifically targeting MuSCs, we used a human myogenic progenitor high-content imaging screen of natural molecules from food to identify nicotinamide (NAM) and pyridoxine (PN) as bioactive nutrients that stimulate MuSCs and have a history of safe human use. NAM and PN synergize via CK1-mediated cytoplasmic β-catenin activation and AKT signaling to promote amplification and differentiation of MuSCs. Oral treatment with a combination of NAM and PN accelerated muscle regeneration in vivo by stimulating MuSCs, increased muscle strength during recovery, and overcame MuSC dysfunction and regenerative failure during aging. Levels of NAM and bioactive PN spontaneously declined during aging in model organisms and interindependently associated with muscle mass and walking speed in a cohort of 186 aged people. Collectively, our results establish the NAM/PN combination as a nutritional intervention that stimulates MuSCs, enhances muscle regeneration, and alleviates age-related muscle decline with a direct opportunity for clinical translation.
Authors
Sara Ancel, Joris Michaud, Eugenia Migliavacca, Charline Jomard, Aurélie Fessard, Pauline Garcia, Sonia Karaz, Sruthi Raja, Guillaume E. Jacot, Thibaut Desgeorges, José L. Sánchez-García, Loic Tauzin, Yann Ratinaud, Benjamin Brinon, Sylviane Métairon, Lucas Pinero, Denis Barron, Stephanie Blum, Leonidas G. Karagounis, Ramin Heshmat, Afshin Ostovar, Farshad Farzadfar, Isabella Scionti, Rémi Mounier, Julien Gondin, Pascal Stuelsatz, Jerome N. Feige
×Abstract
Estrogen receptor-positive (ER+) breast cancer commonly disseminates to bone marrow, where interactions with mesenchymal stromal cells (MSCs) shape disease trajectory. We modeled these interactions with tumor-MSC co-cultures and used an integrated transcriptome-proteome-network-analyses workflow to identify a comprehensive catalog of contact-induced changes. Conditioned media from MSCs failed to recapitulate genes and proteins, some borrowed and others tumor-intrinsic, induced in cancer cells by direct contact. Protein-protein interaction networks revealed the rich connectome between “borrowed” and “intrinsic” components. Bioinformatics prioritized one of the borrowed components, CCDC88A/GIV, a multi-modular metastasis-related protein that has recently been implicated in driving a hallmark of cancer, growth signaling autonomy. MSCs transferred GIV protein to ER+ breast cancer cells (that lack GIV) through tunnelling nanotubes via connexin (Cx)43-facilitated intercellular transport. Reinstating GIV alone in GIV-negative breast cancer cells reproduced approximately 20% of both the borrowed and the intrinsic gene induction patterns from contact co-cultures; conferred resistance to anti-estrogen drugs; and enhanced tumor dissemination. Findings provide a multiomic insight into MSC→tumor cell intercellular transport and validate how transport of one such candidate, GIV, from the haves (MSCs) to have-nots (ER+ breast cancer) orchestrates aggressive disease states.
Authors
Saptarshi Sinha, Brennan W. Callow, Alex P. Farfel, Suchismita Roy, Siyi Chen, Maria Masotti, Shrila Rajendran, Johanna M. Buschhaus, Celia R. Espinoza, Kathryn E. Luker, Pradipta Ghosh, Gary D. Luker
×Abstract
Ecotropic viral integration site 1 (EVI1/MECOM) is frequently upregulated in myeloid malignancies. Here, we present an Evi1-transgenic mouse model with inducible expression in hematopoietic stem/progenitor cells (HSPCs). Upon induction of Evi1 expression, mice displayed anemia, thrombocytopenia, lymphopenia, and erythroid and megakaryocyte dysplasia with a significant expansion of committed myeloid progenitor cells, resembling human myelodysplastic syndrome/myeloproliferative neoplasm–like (MDS/MPN–like) disease. Evi1 overexpression prompted HSPCs to exit quiescence and accelerated their proliferation, leading to expansion of committed myeloid progenitors while inhibiting lymphopoiesis. Analysis of global gene expression and Evi1 binding site profiling in HSPCs revealed that Evi1 directly upregulated lysine demethylase 6b (Kdm6b). Subsequently, Kdm6b-mediated H3K27me3 demethylation resulted in activation of various genes, including Laptm4b. Interestingly, KDM6B and LAPTM4B are positively correlated with EVI1 expression in patients with MDS. The EVI1/KDM6B/H3K27me3/LAPTM4B signaling pathway was also identified in EVI1hi human leukemia cell lines. We found that hyperactivation of the LAPTM4B-driven mTOR pathway was crucial for the growth of EVI1hi leukemia cells. Knockdown of Laptm4b partially rescued Evi1-induced abnormal hematopoiesis in vivo. Thus, our study establishes a mouse model to investigate EVI1hi myeloid malignancies, demonstrating the significance of the EVI1-mediated KDM6B/H3K27me3/LAPTM4B signaling axis in their maintenance.
Authors
Qiong Wu, Chunjie Yu, Fang Yu, Yiran Guo, Yue Sheng, Liping Li, Yafang Li, Yutao Zhang, Chao Hu, Jue Wang, Tong-chuan He, Yong Huang, Hongyu Ni, Zhiguang Huo, Wenshu Wu, Gang Greg Wang, Jianxin Lyu, Zhijian Qian
×Endothelial BMAL1 decline during aging leads to bone loss by destabilizing extracellular fibrillin-1
Abstract
The occurrence of aging is intricately associated with alterations in circadian rhythms that coincide with stem cell exhaustion. Nonetheless, the extent to which the circadian system governs skeletal aging remains inadequately understood. Here, we noticed that skeletal aging in male mice was accompanied by a decline in a core circadian protein, BMAL1, especially in bone marrow endothelial cells (ECs). Using male mice with endothelial KO of aryl hydrocarbon receptor nuclear translocator–like protein 1 (Bmal1), we ascertained that endothelial BMAL1 in bone played a crucial role in ensuring the stability of an extracellular structural component, fibrillin-1 (FBN1), through regulation of the equilibrium between the extracellular matrix (ECM) proteases thrombospondin type 1 domain–containing protein 4 (THSD4) and metalloproteinase with thrombospondin motifs 4 (ADAMTS4), which promote FBN1 assembly and breakdown, respectively. The decline of endothelial BMAL1 during aging prompted excessive breakdown of FBN1, leading to persistent activation of TGF-β/SMAD3 signaling and exhaustion of bone marrow mesenchymal stem cells. Meanwhile, the free TGF-β could promote osteoclast formation. Further analysis revealed that activation of ADAMTS4 in ECs lacking BMAL1 was stimulated by TGF-β/SMAD3 signaling through an ECM-positive feedback mechanism, whereas THSD4 was under direct transcriptional control by endothelial BMAL1. Our investigation has elucidated the etiology of bone aging in male mice by defining the role of ECs in upholding the equilibrium within the ECM, consequently coordinating osteogenic and osteoclastic activities and retarding skeletal aging.
Authors
Ying Yin, Qingming Tang, Jingxi Yang, Shiqi Gui, Yifan Zhang, Yufeng Shen, Xin Zhou, Shaoling Yu, Guangjin Chen, Jiwei Sun, Zhenshuo Han, Luoying Zhang, Lili Chen
×Abstract
Previous studies highlight the potential for sodium-glucose cotransporter type 2 (SGLT2) inhibitors (SGLT2i) to exert cardioprotective effects in heart failure by increasing plasma ketones and shifting myocardial fuel utilization toward ketone oxidation. However, SGLT2i have multiple in vivo effects and the differential impact of SGLT2i treatment and ketone supplementation on cardiac metabolism remains unclear. Here, using gas chromatography–mass spectrometry (GC-MS) and liquid chromatography–tandem mass spectrometry (LC-MS/MS) methodology combined with infusions of [13C6]glucose or [13C4]βOHB, we demonstrate that acute SGLT2 inhibition with dapagliflozin shifts relative rates of myocardial mitochondrial metabolism toward ketone oxidation, decreasing pyruvate oxidation with little effect on fatty acid oxidation in awake rats. Shifts in myocardial ketone oxidation persisted when plasma glucose levels were maintained. In contrast, acute βOHB infusion similarly augmented ketone oxidation, but markedly reduced fatty acid oxidation and did not alter glucose uptake or pyruvate oxidation. After inducing heart failure, dapagliflozin increased relative rates of ketone and fatty acid oxidation, but decreased pyruvate oxidation. Dapagliflozin increased mitochondrial redox and reduced myocardial oxidative stress in heart failure, which was associated with improvements in left ventricular ejection fraction after 3 weeks of treatment. Thus, SGLT2i have pleiotropic effects on systemic and heart metabolism, which are distinct from ketone supplementation and may contribute to the long-term cardioprotective benefits of SGLT2i.
Authors
Leigh Goedeke, Yina Ma, Rafael C. Gaspar, Ali Nasiri, Jieun Lee, Dongyan Zhang, Katrine Douglas Galsgaard, Xiaoyue Hu, Jiasheng Zhang, Nicole Guerrera, Xiruo Li, Traci LaMoia, Brandon T. Hubbard, Sofie Haedersdal, Xiaohong Wu, John Stack, Sylvie Dufour, Gina Marie Butrico, Mario Kahn, Rachel J. Perry, Gary W. Cline, Lawrence H. Young, Gerald I. Shulman
×Abstract
Myocardial infarction (MI) is characterized by massive cardiomyocyte (CM) death and cardiac dysfunction, and effective therapies to achieve cardioprotection are greatly needed. Here, we report that flavin-containing monooxygenase 2 (FMO2) levels were markedly increased in CMs in both ex vivo and in vivo models of ischemic injury. Genetic deletion of FMO2 resulted in reduced CM survival and enhanced cardiac dysfunction, whereas CM-specific FMO2 overexpression conferred a protective effect in infarcted rat hearts. Mechanistically, FMO2 inhibited the activation of ER stress–induced apoptotic proteins, including caspase 12 and C/EBP homologous protein (CHOP), by downregulating the unfolded protein response pathway. Furthermore, we identified FMO2 as a chaperone that catalyzes disulfide bond formation in unfolded and misfolded proteins through its GVSG motif. GVSG-mutated FMO2 failed to catalyze disulfide bond formation and lost its protection against ER stress and CM death. Finally, we demonstrated the protective effect of FMO2 in a human induced pluripotent stem cell–derived CM model. Collectively, this study highlights FMO2 as a key modulator of oxidative protein folding in CMs and underscores its therapeutic potential for treating ischemic heart disease.
Authors
Qingnian Liu, Jiniu Huang, Hao Ding, Yue Tao, Jinliang Nan, Changchen Xiao, Yingchao Wang, Rongrong Wu, Cheng Ni, Zhiwei Zhong, Wei Zhu, Jinghai Chen, Chenyun Zhang, Xiao He, Danyang Xiong, Xinyang Hu, Jian’an Wang
×Abstract
Heritable forms of hypertrophic cardiomyopathy (HCM) and dilated cardiomyopathy (DCM) represent starkly diverging clinical phenotypes, yet may be caused by mutations to the same sarcomeric protein. The precise mechanisms by which point mutations within the same gene bring about phenotypic diversity remain unclear. Our objective was to develop a mechanistic explanation of diverging phenotypes in two TPM1 mutations, E62Q (HCM) and E54K (DCM). Drawing on data from the literature and experiments with stem cell–derived cardiomyocytes expressing the TPM1 mutations of interest, we constructed computational simulations that provide plausible explanations of the distinct muscle contractility caused by each variant. In E62Q, increased calcium sensitivity and hypercontractility was explained most accurately by a reduction in effective molecular stiffness of tropomyosin and alterations in its interactions with the actin thin filament that favor the “closed” regulatory state. By contrast, the E54K mutation appeared to act via long-range allosteric interactions to increase the association rate of the C-terminal troponin I mobile domain to tropomyosin/actin. These mutation-linked molecular events produced diverging alterations in gene expression that can be observed in human engineered heart tissues. Modulators of myosin activity confirmed our proposed mechanisms by rescuing normal contractile behavior in accordance with predictions.
Authors
Saiti S. Halder, Michael J. Rynkiewicz, Lynne Kim, Meaghan E. Barry, Ahmed G.A. Zied, Lorenzo R. Sewanan, Jonathan A. Kirk, Jeffrey R. Moore, William J. Lehman, Stuart G. Campbell
×Abstract
BACKGROUND Despite an overall poor prognosis, about 15% of patients with advanced-stage tubo-ovarian high-grade serous carcinoma (HGSC) survive 10 or more years after standard treatment.METHODS We evaluated the tumor microenvironment of this exceptional, understudied group using a large international cohort enriched for long-term survivors (LTS; 10+ years; n = 374) compared with mid-term (MTS; 5–7.99 years; n = 433) and short-term survivors (STS; 2–4.99 years; n = 416). Primary tumor samples were immunostained and scored for intraepithelial and intrastromal densities of 10 immune-cell subsets (including T cells, B cells, plasma cells, myeloid cells, PD-1+ cells, and PD-L1+ cells) and epithelial content.RESULTS Positive associations with LTS compared with STS were seen for 9 of 10 immune-cell subsets. In particular, the combination of intraepithelial CD8+ T cells and intrastromal B cells showed near 5-fold increased odds of LTS compared with STS. All of these associations were stronger in tumors with high epithelial content and/or the C4/Differentiated molecular subtype, despite immune-cell densities generally being higher in tumors with low epithelial content and/or the C2/Immunoreactive molecular subtype.CONCLUSION The tumor microenvironment of HGSC LTS is distinguished by the intersection of T and B cell coinfiltration, high epithelial content, and C4/differentiated molecular subtype, features which may inspire new approaches to immunotherapy.FUNDING Ovarian Cancer Research Program (OCRP) of the Congressionally Directed Medical Research Program (CDMRP), U.S. Department of Defense (DOD); American Cancer Society; BC Cancer Foundation; Canada’s Networks of Centres of Excellence; Canadian Cancer Society; Canadian Institutes of Health Research; Cancer Councils of New South Wales, Victoria, Queensland, South Australia, and Tasmania, Cancer Foundation of Western Australia; Cancer Institute NSW; Cancer Research UK; Deutsche Forschungsgesellschaft; ELAN Funds of the University of Erlangen-Nuremberg; Fred C. and Katherine B. Andersen Foundation; Genome BC; German Cancer Research Center; German Federal Ministry of Education and Research, Programme of Clinical Biomedical Research; Instituto de Salud Carlos III; Mayo Foundation; Minnesota Ovarian Cancer Alliance; Ministerio de Economía y Competitividad; Medical Research Council (MRC); National Center for Advancing Translational Sciences; National Health and Medical Research Council of Australia (NHMRC); Ovarian Cancer Australia; Peter MacCallum Foundation; Sydney West Translational Cancer Research Centre; Terry Fox Research Institute; The Eve Appeal (The Oak Foundation); UK National Institute for Health Research Biomedical Research Centres at the University of Cambridge; University of Pittsburgh School of Medicine; U.S. National Cancer Institute of the National Institutes of Health; VGH & UBC Hospital Foundation; Victorian Cancer Agency.
Authors
Brad H. Nelson, Phineas Hamilton, Minh Tung Phung, Katy Milne, Bronwyn Harris, Shelby Thornton, Donald Stevens, Shreena Kalaria, Karanvir Singh, Céline M. Laumont, Elena Moss, Aliya Alimujiang, Nicola S. Meagher, Adelyn Bolithon, Sian Fereday, Catherine J. Kennedy, Joy Hendley, Dinuka Ariyaratne, Kathryn Alsop, Nadia Traficante, Ellen L. Goode, Anthony Karnezis, Hui Shen, Jean Richardson, Cindy McKinnonDeurloo, Anne Chase, Bronwyn Grout, Jennifer Anne Doherty, Holly R. Harris, Kara L. Cushing-Haugen, Michael Anglesio, Karolin Heinze, David Huntsman, Aline Talhouk, Gillian E. Hanley, Jennifer Alsop, Mercedes Jimenez-Linan, Paul D.P. Pharoah, Jessica Boros, Alison H. Brand, Paul R. Harnett, Raghwa Sharma, Jonathan L. Hecht, Naoko Sasamoto, Kathryn L. Terry, Beth Karlan, Jenny Lester, Michael E. Carney, Marc T. Goodman, Brenda Y. Hernandez, Lynne R. Wilkens, Sabine Behrens, Renée Turzanski Fortner, Peter A. Fasching, Christiani Bisinotto, Francisco José Candido dos Reis, Prafull Ghatage, Martin Köbel, Esther Elishaev, Francesmary Modugno, Linda Cook, Nhu Le, Aleksandra Gentry-Maharaj, Usha Menon, María J. García, Cristina Rodriguez-Antona, Kyo Farrington, Linda E. Kelemen, Stefan Kommoss, Annette Staebler, Dale W. Garsed, James D. Brenton, Anna M. Piskorz, David D.L. Bowtell, Anna DeFazio, Susan J. Ramus, Malcolm C. Pike, Celeste Leigh Pearce
×Abstract
The pathobiont Staphylococcus aureus (Sa) induces nonprotective antibody imprints that underlie ineffective staphylococcal vaccination. However, the mechanism by which Sa modifies antibody activity is not clear. Herein, we demonstrate that IL-10 is the decisive factor that abrogates antibody protection in mice. Sa-induced B10 cells drive antigen-specific vaccine suppression that affects both recalled and de novo developed B cells. Released IL-10 promotes STAT3 binding upstream of the gene encoding sialyltransferase ST3gal4 and increases its expression by B cells, leading to hyper-α2,3sialylation of antibodies and loss of protective activity. IL-10 enhances α2,3sialylation on cell-wall–associated IsdB, IsdA, and MntC antibodies along with suppression of the respective Sa vaccines. Consistent with mouse findings, human anti-Sa antibodies as well as anti-pseudomonal antibodies from cystic fibrosis subjects (high IL-10) are hypersialylated, compared with anti–Streptococcus pyogenes and pseudomonal antibodies from normal individuals. Overall, we demonstrate a pathobiont-centric mechanism that modulates antibody glycosylation through IL-10, leading to loss of staphylococcal vaccine efficacy.
Authors
Chih-Ming Tsai, Irshad A. Hajam, J.R. Caldera, Austin W.T. Chiang, Cesia Gonzalez, Xin Du, Biswa Choudhruy, Haining Li, Emi Suzuki, Fatemeh Askarian, Ty’Tianna Clark, Brian Lin, Igor H. Wierzbicki, Angelica M. Riestra, Douglas J. Conrad, David J. Gonzalez, Victor Nizet, Nathan E. Lewis, George Y. Liu
×Abstract
Effective antitumor T cell activity relies on the expression and MHC presentation of tumor neoantigens. Tumor cells can evade T cell detection by silencing the transcription of antigens or by altering MHC machinery, resulting in inadequate neoantigen-specific T cell activation. We identified the DNA–protein kinase inhibitor (DNA-PKi) NU7441 as a promising immunomodulator that reduced immunosuppressive proteins, while increasing MHC-I expression in a panel of human melanoma cell lines. In tumor-bearing mice, combination therapy using NU7441 and the immune adjuvants stimulator of IFN genes (STING) ligand and the CD40 agonist NU-SL40 substantially increased and diversified the neoantigen landscape, antigen-presenting machinery, and, consequently, substantially increased both the number and repertoire of neoantigen-reactive, tumor-infiltrating lymphocytes (TILs). DNA-PK inhibition or KO promoted transcription and protein expression of various neoantigens in human and mouse melanomas and induced sensitivity to immune checkpoint blockade (ICB) in resistant tumors. In patients, protein kinase, DNA-activated catalytic subunit (PRKDC) transcript levels were inversely correlated with MHC-I expression and CD8+ TILs but positively correlated with increased neoantigen loads and improved responses to ICB. These studies suggest that inhibition of DNA-PK activity can restore tumor immunogenicity by increasing neoantigen expression and presentation and broadening the neoantigen-reactive T cell population.
Authors
Allison J. Nielsen, Gabriella K. Albert, Amelia Sanchez, Jiangli Chen, Jing Liu, Andres S. Davalos, Degui Geng, Xander Bradeen, Jennifer D. Hintzsche, William Robinson, Martin McCarter, Carol Amato, Richard Tobin, Kasey Couts, Breelyn A. Wilky, Eduardo Davila
×Abstract
Prostate cancer is the second leading cause of male cancer death in the U.S. Current immune checkpoint inhibitor–based immunotherapies have improved survival for many malignancies; however, they have failed to prolong survival for prostate cancer. Siglecs (sialic acid–binding immunoglobulin-like lectins) are expressed on immune cells and regulate their function. Siglec-7 and Siglec-9 contribute to immune evasion in cancer by interacting with sialic acid–containing glycoprotein ligands on cancer cells. However, the role of Siglec-7/9 receptors and their ligands in prostate cancer remains poorly understood. Here, we find that Siglec-7 and Siglec-9 are associated with poor prognosis in patients with prostate cancer and are highly expressed in myeloid cells, including macrophages, in prostate tumor tissues. Siglec-7 and -9 ligands were expressed in prostate cancer cells and human prostate tumor tissues. Blocking the interactions between Siglec-7/9 and sialic acids inhibited prostate cancer xenograft growth and increased immune cell infiltration in humanized mice in vivo. Using a CRISPRi screen and mass spectrometry, we identified CD59 as a candidate Siglec-9 ligand in prostate cancer. The identification of Siglec-7 and -9 as potential therapeutic targets, including the CD59/Siglec-9 axis, opens up opportunities for immune-based interventions in prostate cancer.
Authors
Ru M. Wen, Jessica C. Stark, G. Edward W. Marti, Zenghua Fan, Aram Lyu, Fernando Jose Garcia Marques, Xiangyue Zhang, Nicholas M. Riley, Sarah M. Totten, Abel Bermudez, Rosalie Nolley, Hongjuan Zhao, Lawrence Fong, Edgar G. Engleman, Sharon J. Pitteri, Carolyn R. Bertozzi, James D. Brooks
×Abstract
The trafficking dynamics of uromodulin (UMOD), the most abundant protein in human urine, play a critical role in the pathogenesis of kidney disease. Monoallelic mutations in the UMOD gene cause autosomal dominant tubulointerstitial kidney disease (ADTKD-UMOD), an incurable genetic disorder that leads to kidney failure. The disease is caused by the intracellular entrapment of mutant UMOD in kidney epithelial cells, but the precise mechanisms mediating disrupted UMOD trafficking remain elusive. Here, we report that transmembrane Emp24 protein transport domain–containing (TMED) cargo receptors TMED2, TMED9, and TMED10 bind UMOD and regulate its trafficking along the secretory pathway. Pharmacological targeting of TMEDs in cells, in human kidney organoids derived from patients with ADTKD-UMOD, and in mutant-UMOD-knockin mice reduced intracellular accumulation of mutant UMOD and restored trafficking and localization of UMOD to the apical plasma membrane. In vivo, the TMED-targeted small molecule also mitigated ER stress and markers of kidney damage and fibrosis. Our work reveals TMED-targeting small molecules as a promising therapeutic strategy for kidney proteinopathies.
Authors
Silvana Bazua-Valenti, Matthew R. Brown, Jason Zavras, Magdalena Riedl Khursigara, Elizabeth Grinkevich, Eriene-Heidi Sidhom, Keith H. Keller, Matthew Racette, Moran Dvela-Levitt, Catarina Quintanova, Hasan Demirci, Sebastian Sewerin, Alissa C. Goss, John Lin, Hyery Yoo, Alvaro S. Vaca Jacome, Malvina Papanastasiou, Namrata Udeshi, Steven A. Carr, Nina Himmerkus, Markus Bleich, Kerim Mutig, Sebastian Bachmann, Jan Halbritter, Stanislav Kmoch, Martina Živná, Kendrah Kidd, Anthony J. Bleyer, Astrid Weins, Seth L. Alper, Jillian L. Shaw, Maria Kost-Alimova, Juan Lorenzo B. Pablo, Anna Greka
×Abstract
BRAFV600E-mutant metastatic colorectal cancer (mCRC) is associated with poor prognosis. The combination of anti-BRAF/anti-EGFR (encorafenib/cetuximab) treatment for patients with BRAFV600E-mutant mCRC improves clinical benefits; unfortunately, inevitable acquired resistance limits the treatment outcome, and the mechanism has not been validated. Here, we discovered that monoacylglycerol O-acyltransferase 3–mediated (MOGAT3-mediated) diacylglycerol (DAG) accumulation contributed to acquired resistance to encorafenib/cetuximab by dissecting a BRAFV600E-mutant mCRC patient–derived xenograft (PDX) model exposed to encorafenib/cetuximab administration. Mechanistically, the upregulated MOGAT3 promoted DAG synthesis and reduced fatty acid oxidation–promoting DAG accumulation and activated PKCα/CRAF/MEK/ERK signaling, driving acquired resistance. Resistance-induced hypoxia promoted MOGAT3 transcriptional elevation; simultaneously, MOGAT3-mediated DAG accumulation increased HIF1A expression at the translation level through PKCα/CRAF/eIF4E activation, strengthening the resistance status. Intriguingly, reducing intratumoral DAG with fenofibrate or PF-06471553 restored the antitumor efficacy of encorafenib/cetuximab in resistant BRAFV600E-mutant mCRC, which interrupted PKCα/CRAF/MEK/ERK signaling. These findings reveal the critical role of the metabolite DAG as a modulator of encorafenib/cetuximab efficacy in BRAFV600E-mutant mCRC, suggesting that fenofibrate might prove beneficial for resistant BRAFV600E-mutant mCRC patients.
Authors
Jiawei Wang, Huogang Wang, Wei Zhou, Xin Luo, Huijuan Wang, Qing Meng, Jiaxin Chen, Xiaoyu Chen, Yingqiang Liu, David W. Chan, Zhenyu Ju, Zhangfa Song
×Abstract
Following a meal, glucagon-like peptide 1 (GLP1) and glucose-dependent insulinotropic polypeptide (GIP), the 2 major incretins promoting insulin release, are secreted from specialized enteroendocrine cells (L and K cells, respectively). Although GIP is the dominant incretin in humans, the detailed molecular mechanisms governing its release remain to be explored. GIP secretion is regulated by the activity of G protein–coupled receptors (GPCRs) expressed by K cells. GPCRs couple to 1 or more specific classes of heterotrimeric G proteins. In the present study, we focused on the potential metabolic roles of K cell Gs. First, we generated a mouse model that allowed us to selectively stimulate K cell Gs signaling. Second, we generated a mouse strain harboring an inactivating mutation of Gnas, the gene encoding the α-subunit of Gs, selectively in K cells. Metabolic phenotyping studies showed that acute or chronic stimulation of K cell Gs signaling greatly improved impaired glucose homeostasis in obese mice and in a mouse model of type 2 diabetes, due to enhanced GIP secretion. In contrast, K cell–specific Gnas-KO mice displayed markedly reduced plasma GIP levels. These data strongly suggest that strategies aimed at enhancing K cell Gs signaling may prove useful for the treatment of diabetes and related metabolic diseases.
Authors
Antwi-Boasiako Oteng, Liu Liu, Yinghong Cui, Oksana Gavrilova, Huiyan Lu, Min Chen, Lee S. Weinstein, Jonathan E. Campbell, Jo E. Lewis, Fiona M. Gribble, Frank Reimann, Jürgen Wess
×Abstract
Acute respiratory distress syndrome (ARDS) is associated with significant morbidity and mortality, and neutrophils are critical to its pathogenesis. Neutrophil activation is closely regulated by inhibitory tyrosine phosphatases including Src homology region 2 domain–containing phosphatase-1 (Shp1). Here, we report that loss of neutrophil Shp1 in mice produced hyperinflammation and lethal pulmonary hemorrhage in sterile inflammation and pathogen-induced models of acute lung injury (ALI) through a Syk kinase–dependent mechanism. We observed large intravascular neutrophil clusters, perivascular inflammation, and excessive neutrophil extracellular traps in neutrophil-specific Shp1-KO mice, suggesting an underlying mechanism for the observed pulmonary hemorrhage. Targeted immunomodulation through the administration of a Shp1 activator (SC43) reduced agonist-induced reactive oxygen species in vitro and ameliorated ALI-induced alveolar neutrophilia and NETs in vivo. We propose that the pharmacologic activation of Shp1 has the potential to fine tune neutrophil hyperinflammation that is central to the pathogenesis of ARDS.
Authors
S. Farshid Moussavi-Harami, Simon J Cleary, Mélia Magnen, Yurim Seo, Catharina Conrad, Bevin C. English, Longhui Qiu, Kristin M. Wang, Clare L. Abram, Clifford A. Lowell, Mark R. Looney
×Abstract
mRNA vaccines have demonstrated efficacy during the COVID-19 pandemic and are now being investigated for multiple diseases. However, concerns linger about the durability of immune responses, and the high incidence of breakthrough infections among vaccinated individuals highlights the need for improved mRNA vaccines. In this study, we investigated the effects of reinforcing costimulation via 4-1BB, a member of the TNF receptor superfamily, on immune responses elicited by mRNA vaccines. We first immunized mice with mRNA vaccines, followed by treatment with 4-1BB costimulatory antibodies to reinforce the 4-1BB pathway at different time points after vaccination. Consistent with prior studies, reinforcing 4-1BB costimulation on the day of vaccination did not result in a substantial improvement in vaccine responses. However, reinforcing 4-1BB costimulation on day 4 after vaccination, when 4-1BB expression levels were highest, resulted in a profound improvement in CD8+ T cell responses associated with enhanced protection against pathogen challenges. A similar clinical benefit was observed in a therapeutic cancer vaccine model. We also report time-dependent effects with OX40, another costimulatory molecule of the TNF receptor superfamily. These findings demonstrate that delayed reinforcement of costimulation may exert an immunologic benefit, providing insights for the development of more effective mRNA vaccines for infectious diseases and cancer.
Authors
Sarah Sanchez, Tanushree Dangi, Bakare Awakoaiye, Min Han Lew, Nahid Irani, Slim Fourati, Pablo Penaloza-MacMaster
×Abstract
BACKGROUND In type 1 diabetes (T1D), impaired insulin sensitivity may contribute to the development of diabetic kidney disease (DKD) through alterations in kidney oxidative metabolism.METHODS Young adults with T1D (n = 30) and healthy controls (HCs) (n = 20) underwent hyperinsulinemic-euglycemic clamp studies, MRI, 11C-acetate PET, kidney biopsies, single-cell RNA-Seq, and spatial metabolomics to assess this relationship.RESULTS Participants with T1D had significantly higher glomerular basement membrane (GBM) thickness compared with HCs. T1D participants exhibited lower insulin sensitivity and cortical oxidative metabolism, correlating with higher insulin sensitivity. Proximal tubular transcripts of TCA cycle and oxidative phosphorylation enzymes were lower in T1D. Spatial metabolomics showed reductions in tubular TCA cycle intermediates, indicating mitochondrial dysfunction. The Slingshot algorithm identified a lineage of proximal tubular cells progressing from stable to adaptive/maladaptive subtypes, using pseudotime trajectory analysis, which computationally orders cells along a continuum of states. This analysis revealed distinct distribution patterns between T1D and HCs, with attenuated oxidative metabolism in T1D attributed to a greater proportion of adaptive/maladaptive subtypes with low expression of TCA cycle and oxidative phosphorylation transcripts. Pseudotime progression associated with higher HbA1c, BMI, and GBM, and lower insulin sensitivity and cortical oxidative metabolism.CONCLUSION These early structural and metabolic changes in T1D kidneys may precede clinical DKD.TRIAL REGISTRATION ClinicalTrials.gov NCT04074668.FUNDING University of Michigan O’Brien Kidney Translational Core Center grant (P30 DK081943); CROCODILE studies by National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) (P30 DK116073), Juvenile Diabetes Research Foundation (JDRF) (2-SRA-2019-845-S-B), Boettcher Foundation, Intramural Research Program at NIDDK and Centers for Disease Control and Prevention (CKD Initiative) under Inter-Agency Agreement #21FED2100157DPG.
Authors
Ye Ji Choi, Gabriel Richard, Guanshi Zhang, Jeffrey B. Hodgin, Dawit S. Demeke, Yingbao Yang, Jennifer A. Schaub, Ian M. Tamayo, Bhupendra K. Gurung, Abhijit S. Naik, Viji Nair, Carissa Birznieks, Alexis MacDonald, Phoom Narongkiatikhun, Susan Gross, Lynette Driscoll, Maureen Flynn, Kalie Tommerdahl, Kristen J. Nadeau, Viral N. Shah, Tim Vigers, Janet K. Snell-Bergeon, Jessica Kendrick, Daniel H. van Raalte, Lu-Ping Li, Pottumarthi Prasad, Patricia Ladd, Bennett B. Chin, David Z. Cherney, Phillip J. McCown, Fadhl Alakwaa, Edgar A. Otto, Frank C. Brosius, Pierre Jean Saulnier, Victor G. Puelles, Jesse A. Goodrich, Kelly Street, Manjeri A. Venkatachalam, Aaron Ruiz, Ian H. de Boer, Robert G. Nelson, Laura Pyle, Denis P. Blondin, Kumar Sharma, Matthias Kretzler, Petter Bjornstad
Copyright © 2024 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)