EGFR-mutant lung adenocarcinomas (LUADs) that are vulnerable to the EGFR antagonist osimertinib (Osi) eventually relapse, owing in part to the emergence of drug-tolerant persister (DTP) cells that arise through epigenetic mechanisms. Intratumoral DTP cells can herald a worse clinical outcome, but the way in which DTP cells influence LUAD progression remains unclear. Osi-resistant (OR) cells exhibit typical DTP cell features, including a propensity to undergo senescence and epithelial-mesenchymal transition (EMT), which can activate heightened secretory states. Therefore, we postulated that OR cells influence LUAD progression through paracrine mechanisms. To test this hypothesis, we utilized congenic pairs of EGFR-mutant LUAD cell lines in which drug-naive (DN) cells were rendered OR by chronic exposure to escalating doses of Osi. Cocultured in vitro or coinjected into mice, paracrine signals from OR cells enhanced the growth and metastatic properties of DN cells. EMT and senescence-activated nonoverlapping secretomes, and OR cells governed DN cells by undergoing EMT but not senescence. Mechanistically, Osi rapidly increased TGF-β2 levels to initiate EMT, which triggered a Golgi remodeling process that accelerated the biogenesis and anterograde trafficking of secretory vesicles. The protumorigenic activity of OR cells was diminished by depletion of EMT-dependent secreted proteins or the EMT-activating transcription factor ZEB1. These findings identify paracrine mechanisms by which OR cells drive LUAD progression.
Madhurima Ghosh, Chao Wu, Abhishek Kumar, Monique Nilsson, John V. Heymach, Weina Zhao, Jiang Yu, Xin Liu, Na Ding, Shike Wang, Guan-Yu Xiao, Angelo Chen, Kate Grimley, William K. Russell, Chad J. Creighton, Xiaochao Tan, Jonathan M. Kurie
KRAS mutations serve as key oncogenic drivers in the initiation and progression of pancreatic ductal adenocarcinoma (PDAC). Despite the advancement of KRAS inhibitors, such as MRTX1133, for PDAC treatment, intrinsic and acquired resistance remain major barriers to their clinical efficacy. This study underscored the role of histone deacetylase 5 (HDAC5) loss in mediating intrinsic resistance to KRASG12D inhibitors. Mechanistically, HDAC5 promoted c-Myc degradation by deacetylating K148, thereby facilitating NEDD4-mediated ubiquitination at this site. The loss of HDAC5 resulted in hyperacetylation of c-Myc at K148, impeding the ubiquitination and subsequent degradation process of c-Myc following deacetylation. Consequently, c-Myc stability and transcriptional activity were sustained even under KRAS/MEK/ERK pathway inhibition, reinforcing MAPK signaling and promoting cell survival despite KRAS suppression. Our data further demonstrated that pharmacological or genetic inhibition of c-Myc effectively reversed the resistance phenotype mediated by HDAC5 loss, suggesting a therapeutic strategy centered on KRAS-MYC dual-node blockade. Furthermore, the expression levels of HDAC5 and the acetylation status of c-Myc may serve as biomarkers for predicting the therapeutic response to MRTX1133. These findings provide insights into overcoming resistance to KRASG12D inhibitors and offer potential biomarkers and combinatorial therapeutic strategies for precision treatment of PDAC.
Taoyu Chen, Haixin Yu, Keshan Wang, Gengdu Qin, Yuhan Zhao, Xueyi Liang, Yuxuan Li, Tianhao Zou, Jiaying Liu, Jingyuan Zhao, Zhiqiang Liu, Ruozheng Wei, Bo Wang, Shanmiao Gou, Tao Yin, Heshui Wu, Xin Jin, Yingke Zhou
Autoimmune factor XIII (FXIII) deficiency is a rare hemorrhagic disease characterized by severe bleeding and a high mortality rate. However, the pathogenesis of this disease remains unclear. FXIII consumption caused by infections is becoming increasingly common. Our clinical investigation, combined with in vivo experiments, revealed that patients and mice with autoimmune FXIII deficiency displayed complement dysfunction and that pathogenic infection and autoantibody generation were positively correlated. Further analysis revealed the presence of combined FXIII-C3 autoantibodies in patients with autoimmune FXIII deficiency. These combined autoantibodies neutralize FXIII, cause bleeding, and form a complex with C3, inhibiting complement activation and complement-mediated adaptive immune responses. Therefore, compromised immune responses increase host susceptibility to pathogenic Candida albicans infections. Consequently, uncontrolled exogenous fungal infections further activate platelets and cause platelet-related CD40 ligand (CD40L) release. By interacting with the CD40 on the B cell surface, the released CD40L further promotes autoreactive B cell activation to produce more autoantibodies, thereby forming a self-amplification loop for the progressive consumption of FXIII. We believe this study provides a perspective on disease pathogenesis and therapeutic guidance for better treatment of autoimmune FXIII deficiency.
Shanshan Luo, Jun Deng, Yue Liu, Lv Xiong, Wanting Wang, Chaofan Wang, Yaohua Cai, Yajie Ding, Bahgat Fayed, Zhipeng Cheng, Lu Zhang, Min Zhang, Jun Fang, Gensheng Zhang, Rui Zhu, Haiqiang Jiang, Yunlun Li, Kun Huang, Xiang Cheng, Liang V. Tang, Chunyan Sun, Heng Mei, Peter F. Zipfel, Huafang Wang, Yadan Wang, Desheng Hu, Yu Hu
Vinculin (VCL), a linker between cells and their environment, has rarely been linked to disease. This study examines the role of VCL in the development of the enteric nervous system (ENS) and its relationship to Hirschsprung disease (HSCR). Using whole-genome sequencing and in vitro assays, we identified 4 VCL mutations associated with HSCR, most causing loss of function. Neural crest–specific Vcl knock-out mice (Vcl cKO) displayed ENS defects resembling short-segment HSCR, including partial colonic aganglionosis and abnormal gut musculature. Single-cell transcriptomics revealed dysregulation of genes involved in neuronal differentiation and MAPK signaling. Spatial RNA-seq revealed reduced ENS-mesenchyme interactions in Vcl cKO mice, accompanied by significant disruption of the Pleiotrophin (PTN) pathway; Ptn knock-out mice exhibited phenotypes similar to those of Vcl cKO mice, underscoring the importance of ENS-mesenchyme crosstalk. VCL works as a hub gene crucial for cell connection and signaling pathways essential for ENS formation. VCL deficiency subtly impacts various developmental stages and neighboring cells, cumulatively leading to a phenotype similar to short-segment HSCR. This research highlights the role of VCL in maintaining cellular interactions and signaling pathways, such as MAPK and PTN, which are crucial for ENS development and may inform therapeutic targets for ENS disorders.
Lifang Liu, Xixin Wang, Mingxuan Liang, Peiting Li, Cindy Yifei Yan, Patrick Ho-Yu Chung, Kenneth Kak-Yuen Wong, Asif Javed, Maria-Mercedes Garcia-Barcelo, Elly Sau-Wai Ngan
Adoptive cell therapy (ACT) relies on durable and functional T cells to mediate tumor clearance. Th9 cells are a metabolically fit CD4+ T cell subset with strong persistence but limited cytotoxicity. Here, we identified endomelipeptide A (EpA), a cyclic peptide isolated from Ganoderma lucidum–associated endophytic fungi, as a potent enhancer of Th9 cell differentiation. EpA promoted a cytotoxic Th9 phenotype with enhanced mitochondrial function and metabolic fitness. Mechanistically, EpA dually targeted ZAP70 and SREBP1, coupling T cell receptor signaling activation with lipid metabolism suppression. EpA-treated Th9 cells mediated robust, CD8+ T cell–dependent tumor control and enhanced the efficacy of human Th9 CAR T cell therapy in vivo. These findings establish EpA as a distinct cyclic peptide that reprograms Th9 cells and provides a potential approach to boost ACT efficacy.
Wenli Zhao, Yang Zhou, Yuyang Chen, Yicheng Sun, Jiaxin Tang, Yihan Zhu, Jie Ren, Tianxu Du, Handuo Wang, Yuan Gao, Yu Hu, Ling Jiang, Tomohiko Ohwada, Qi Luo, Enguang Bi
11-cis-Retinal is essential for light perception in mammalian photoreceptors (PRs), and aberrations in retinoid transformations cause severe retinal diseases. Understanding these processes is crucial for combating blinding diseases. The visual cycle, operating within PRs and the retinal pigment epithelium (RPE), regenerates 11-cis-retinal to sustain light sensitivity. Retinoids are also present in Müller glia (MG), hypothesized to supply 11-cis-retinol to cone PRs and retinal ganglion cells (RGCs). To trace retinoid movement through retinal cell types, we used cell-specific knockin of lecithin:retinol acyltransferase (LRAT), which converts retinols into stable retinyl esters (REs). Ectopic LRAT expression in murine PRs, MG, and RGCs resulted in RE synthesis, with REs differing in abundance and isomeric composition across cell types under genetic and light-based perturbations. PR inner segments showed high 11-cis-RE content, suggesting a constant 11-cis-retinoid supply for pigment regeneration. In MG expressing LRAT, all-trans-REs were detected, contrasting with 11-cis-REs in PRs. The MG-specific LRAT phenotype mirrored the RE-rich human neural retina, suggesting human MG may utilize LRAT to maintain retinoid reservoirs. Our findings reveal tightly controlled retinoid flux throughout the mammalian retina that supports sustained vision, expanding understanding of the visual cycle to combat retinal diseases.
Zachary J. Engfer, Grazyna Palczewska, Samuel W. Du, Jianye Zhang, Zhiqian Dong, Carolline Rodrigues Menezes, Jun Wang, Jianming Shao, Budd A. Tucker, Robert F. Mullins, Rui Chen, Philip D. Kiser, Krzysztof Palczewski
During vascular injury, platelets are essential for halting bleeding and recruiting neutrophils to prevent microbial invasion. However, in antibody-mediated autoimmune diseases occurring without vascular damage, neutrophils infiltrate tissues and contribute to pathology. Here, we investigated whether the dependence of neutrophils on platelets is conserved in the context of antibody-driven inflammation. Using human cells from individuals with rheumatoid arthritis and a microfluidic system mimicking physiological shear over IgG-containing immune complexes, we demonstrate that despite expressing Fc receptors, neutrophils required platelets to stably adhere to immune complexes under flow. Platelet Fcγ receptor 2a (FcγRIIA) binding was critical for resisting shear stress, while neutrophils used FcγRIIA and FcγRIIIB for immune complex recognition. Platelet P-selectin binding to neutrophil P-selectin glycoprotein ligand 1 (PSGL-1) was essential for recruitment, whereas macrophage-1 antigen (Mac-1) was dispensable. In a mouse model of autoantibody-mediated arthritis, intravital imaging confirmed that neutrophil recruitment relied on PSGL-1. Importantly, expression of FcγRIIA aggravated arthritis, and blockade of PSGL-1, but not Mac-1, in these mice abrogated both the platelet and neutrophil interactions and disease. These findings identify key molecular interactions in platelet-neutrophil cooperation and reveal that platelets are essential enablers of FcR-mediated neutrophil adhesion in antibody-driven inflammation.
Marie Bellio, Isabelle Allaeys, Etienne Doré, Myriam Vaillancourt, Tania Lévesque, Mélina Monteil, Nicolas Vallières, Philippe Desaulniers, Nicolas Bertrand, Valance A. Washington, Yotis Senis, Steve Lacroix, Paul Fortin, Clémence Belleannée, Eric Boilard
GATA6 is a master regulator of differentiation in the pancreas, and its expression levels determine the 2 main molecular subtypes of pancreatic cancer. High GATA6 levels contribute to the classical pancreatic cancer subtype, which is associated with a higher degree of tumor differentiation and better disease prognosis. However, why GATA6 expression varies across pancreatic cancers and what regulates GATA6 expression remain elusive. Here, we report that oncogenic KRAS-activated ERK signaling suppresses GATA6 transcription in pancreatic cancers. GATA6 mRNA levels inversely correlated with KRAS/ERK activity in pancreatic tumors. A genome-wide CRISPR screen in a GATA6-EGFP reporter knockin cell line identified JUNB as the ERK-regulated transcriptional repressor for GATA6. Active ERK stabilized JUNB protein, while KRAS/ERK inhibition led to ubiquitin-independent proteasomal degradation of JUNB and increased transcription of GATA6. Upregulation of GATA6 enhanced chemosensitivity of pancreatic cancer cells, and KRAS/ERK inhibitors synergized with chemotherapy in a GATA6-dependent manner. Our study identifies how oncogenic KRAS/ERK signaling suppresses GATA6 to cause dedifferentiation in pancreatic cancer. Combining KRAS/ERK inhibitors with standard-of-care chemotherapies could be a promising therapeutic strategy for treating pancreatic cancers.
Zheng Zhong, Xinang Cao, Pei-Ju Liao, Raman Sethi, Jeffrey A. Klomp, Clint A. Stalnecker, Jinmiao Chen, Yue Wan, Channing J. Der, David M. Virshup
Periodontal disease, a bacterial infection affecting a large percentage of the world’s population, is an important risk factor for several systemic diseases and is significantly worsened by diabetes. To investigate how diabetes exacerbates the inflammatory response to bacteria in this disease, we combined insights from murine and human studies. Through single-cell RNA-Seq, we identified a compelling hyperglycemia-driven molecular pathway: the upregulation of CD137L in dendritic cells (DCs) and increased expression of its receptor, CD137, in IL-17+ T cells. The CD137L-CD137 axis emerged as a pivotal mediator of diabetes-induced inflammatory tissue destruction. Antibody-mediated inhibition of CD137L markedly reduced diabetes-driven bone loss, neutrophil recruitment, expansion of γδ T cells, and excessive infiltration by IL-17A+ cells. In vitro studies further validated these findings and established that dysregulation of DCs mediated by high glucose levels dramatically altered γδ T cell activity in co-culture systems via CD137L. The essential role of DCs as CD137L producers in vivo was definitively established through lineage-specific Akt1 deletion, which abrogated CD137L expression in DCs and reversed the adverse effects of hyperglycemia on increased IL-17+ T cells and loss of Tregs in vivo. Conversely, activation of CD137 with an agonist in normal animals recapitulated diabetes-induced abnormalities in the inflammatory response and accelerated bone loss. These findings elucidate a key mechanism underlying diabetes-induced immune dysregulation and inflammatory damage, and point to the CD137L-CD137 pathway as a promising therapeutic target, offering potential insights into mitigating other diabetes-associated complications linked to inflammatory changes.
Xin Huang, Min Liu, Michael V. Gonzalez, Rahul Debnath, Hamideh Afzali, Yongwon Choi, Su Ah Kim, Kang I. Ko, Dana T. Graves
The role of the tumor immune microenvironment (TIME) in modulating responses to antiestrogen therapy in hormone receptor–positive (HR+) breast cancers remains unclear. We analyzed pre- and on-treatment biopsies from patients with HR+ breast cancer treated with letrozole to induce estrogen deprivation (ED). Stromal tumor–infiltrating lymphocytes, assessed by H&E staining, and immune-related gene sets, including IFN-γ signaling genes, measured by RNA-Seq, were increased in ED-resistant tumors. Cyclic immunofluorescence and spatial transcriptomics revealed an abundance of CD8+ T cells and enhanced antigen processing and immune gene signatures in ED-resistant tumors. In this group, the expression of CXCL9, CXCL10, and CXCL11 — chemokine genes involved in CD8+ T cell recruitment — and the CXCR3 receptor were upregulated both before and after letrozole treatment. CXCL11 levels were higher in conditioned media from HR+ breast cancer cells cocultured with CD8+ T cells. Both recombinant CXCL11 and coculture with CD8+ T cells promoted MCF7 and T47D cell growth in estrogen-free conditions. Finally, deletion combined with silencing of the CXCL11 receptors CXCR3 and CXCR7 in MCF7 cells impaired proliferation in response to exogenous CXCL11 and to coculture with CD8+ T cells in estrogen-free conditions. These findings suggest that CD8+ T cell–associated CXCL11 in the TIME modulated the response of HR+ breast cancer cells to estrogen suppression.
Fabiana Napolitano, Yunguan Wang, Dhivya R. Sudhan, Paula I. Gonzalez-Ericsson, Luigi Formisano, Nisha Unni, Shahbano Shakeel, James Z. Zhu, Khushi Ahuja, Lei Guo, María Rosario Chica-Parrado, Yuki Matsunaga, Pamela Luna, Chang-Ching A. Lin, Yasuaki Uemoto, Kyung-Min Lee, Hongli Ma, Nathaniel J. Evans, Alberto Servetto, Saurabh Mendiratta, Spencer D. Barnes, Roberto Bianco, Yisheng V. Fang, Lin Xu, Jeon Lee, Tao Wang, Justin M. Balko, Gordon B. Mills, Marilyne Labrie, Ariella B. Hanker, Carlos L. Arteaga
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