Epidermal growth factor receptor (EGFR)-activating mutations are established biomarkers of resistance to immune checkpoint blockade (ICB) in lung cancer, yet the precise molecular mechanism and effective therapeutic strategies remain elusive. In this study, we show that EGFR overexpression and amplification recapitulate the negative impact of EGFR driver mutations to ICB response, indicating a proactive involvement of EGFR signaling in antagonizing antitumor immune response. Functional studies unveil that EGFR activation suppresses cellular response to interferon-gamma (IFN-γ) following ICB treatment across multiple cancer models. This impairment in IFN-γ responsiveness further limits the upregulation of T cell-recruiting chemokines and antigen presentation, resulting in reduced T cell infiltration and activation, ultimately undermining antitumor immunity. Mechanistically, EGFR promotes SHP2 activation to accelerate STAT1 dephosphorylation, leading to premature termination of the IFN-γ response. SHP2 inhibition restored ICB sensitivity in EGFR-activated tumors, significantly reducing tumor burden while maintaining a favorable safety profile. Our findings suggest that EGFR/SHP2 axis functions as a molecular brake to disrupt the initiation and amplification of IFN-γ mediated anti-tumor response during immunotherapy. This discovery unveils a potential avenue to overcome immunotherapy resistance in EGFR-driven tumors, particularly lung cancer, through SHP2-targeted combination strategies.
Wei-Tao Zhuang, Lan-Lan Pang, Li-Yang Hu, Jun Liao, Jian-Hua Zhan, Ting Li, Ri-Xin Chen, Jia-Ni Zheng, An-Lin Li, Wen-Yan Yu, Tian-Qin Mao, Liang Chen, Yu-Jian Huang, Shao-Dong Hong, Jing Li, Jun-Han Wu, Yi-Ming Zeng, Meng-Juan Yang, Hai-Qing Zeng, Ya-Xiong Zhang, Li Zhang, Wen-Feng Fang
Dysregulation of cell cycle checkpoints is a cancer hallmark with ubiquitination controlled protein stability playing pivotal roles. Although p21, a key cyclin-dependent kinase inhibitor, is tightly regulated by ubiquitin-mediated degradation, the key upstream modulators of its ubiquitination remain incompletely defined. Here, we identify poly(ADP-ribose) glycohydrolase (PARG) as a regulator of p21 stability in gastric cancer (GC) cells. We show that PARG expression is markedly upregulated in GC tissues and correlates with poor patient prognosis. Functional assays revealed that genetic depletion of PARG triggers G2/M phase arrest and impairs GC cell proliferation. Mechanistically, we demonstrate that PARG loss enhances p21 PARylation, which disrupts its association with E3 ubiquitin ligase, thereby reducing K48-linked ubiquitination and leading to p21 protein stabilization. Moreover, we identify lysine residues K161 and K163 as critical sites for PARG-mediated regulation of p21 ubiquitination. Our findings reveal a post-translational regulatory axis in which PARG governs cell cycle progression by modulating the PARylation-dependent ubiquitination of p21. These results broaden the understanding of p21 regulation in cancer and highlight PARG as a potential therapeutic target for GC treatment.
Yangchan Hu, Qimei Bao, Yixing Huang, Yan Wang, Xin Zhao, Junjun Nan, Yuxin Meng, Mingcong Deng, Yuancong Li, Zirui Zhuang, Hanyi He, Dan Zu, Yuke Zhong, Chunkai Zhang, Bing Wang, Ran Li, Yanhua He, Qihan Wang, Min Liu, John A. Tainer, Yin Shi, Xiangdong Cheng, Ji Jing, Zu Ye
Drug-associated environmental cues can trigger drug-seeking behavior and precipitate relapse. In the current study, we identified that the claustrum (CL) connects the ventral tegmental area (VTA) with the medial prefrontal cortex (mPFC), forming the VTA–CL–mPFC circuit. By using methamphetamine (METH) conditioned place preference (CPP) model in male mice, we found that manipulating the VTA–CL–mPFC circuit or CL neuronal ensemble receiving projections from VTA and projecting to mPFC (VTA–CL–mPFC) could disrupt the retrieval of METH-paired context memory, resulting in the blockage of the acquisition of METH CPP in male mice. During the process, dopamine (DA) release and dopamine 1-like receptor (D1R)-mediated the activation of CL neurons were required for the retrieval of METH-induced reward memory in male mice. These findings reveal a midbrain-to-cortical circuit orchestrated by CL neurons, which plays an essential role in the retrieval of drug-paired environmental cue memory.
Ziheng Zhao, Yuhong He, Yang Liu, Quying Feng, Hee Young Kim, Yu Fan, Xiaowei Guan
Short-lived, clade-specific immune responses with limited mucosal priming are limitations faced by current COVID-19 mRNA vaccines. We have developed a nasal booster vaccine candidate that induced robust, sustained, cross-clade, systemic and mucosal protective immunity. Two recombinant Clec9A-specific monoclonal antibodies fused to the Receptor Binding Domain (RBD) from Omicron XBB.1.5 and SARS-CoV-1, respectively were generated. In Comirnaty mRNA-vaccinated mice, boosting with both constructs combined (Clec9AOMNI) induced cross-clade neutralizing antibodies (nAbs) and T-cell responses that were greater in magnitude and more sustained compared to bivalent Comirnaty (BC) mRNA vaccine booster. Persistence of RBD-specific follicular helper CD4+ T cells, germinal centre B cells, and long-lived plasma cells that facilitated affinity maturation, correlated with detection of triple cross-reactive B cells binding the RBDs of SARS-CoV-2 ancestral, XBB.1.5, and SARS-CoV-1. Remarkably, intranasal boosting with Clec9AOMNI elicited robust and durable immunity across the upper and lower airways while concurrently boosting the systemic immunity to levels matching or exceeding those from systemic boosting. Correspondingly, Clec9AOMNI nasal booster conferred superior protection against SARS-CoV-2 challenge compared to BC mRNA booster, with undetectable viral titers in the respiratory tract. Hence, Clec9AOMNI is a promising nasal booster vaccine candidate that has the potential to mitigate pandemic threats from emerging sarbecoviruses.
You Zhi Nicholas CHEANG, Wee Chee Yap, Kirsteen M. TULLETT, Xinlei QIAN, Peck S. TAN, Kiren PURUSHOTORMAN, Wan Yi TAN, Yun Yan MAH, Paul MACARY, Chee Wah TAN, Mireille H. LAHOUD, Sylvie ALONSO
Malignant tumors with TP53 mutations exhibit poor therapeutic outcomes and high recurrence rates. T cell receptor (TCR)-based T cell therapy shows great promise for targeting intracellular cancer neoantigens. However, the immunogenic potential of TP53 hotspot mutations remain poorly characterized. Here, we identify a immunogenic neoantigen derived from the recurrent TP53R248Q mutation, presented by the prevalent Human Leukocyte Antigen (HLA)-A*11:01 allele. Additionally, we isolated a TP53R248Q reactive TCR that specifically recognize the TP53R248Q mutation without any discernable cross-activity to cognate wild-type TP53 or other TP53 mutants at the same codon position. Functional characterization revealed that TP53R248Q TCR-T cells exhibited selectively cytotoxicity against tumor cells expressing both TP53R248Q mutation and HLA-A*11:01 in vitro. Importantly, the adoptive transfer of TP53R248Q TCR-T cells exhibited significant anti-tumor activity in a clinically relevant patient-derived xenograft (PDX) model engrafted with TP53R248Q/HLA-A*11:01 positive human tumor tissues. Collectively, our study validates the immunogenicity of the TP53R248Q hotspot mutation and provides a TCR with high therapeutic potential for the development of T cell therapies targeting TP53R248Q/HLA-A*11:01 positive cancers.
Lianghua Shen, Ziyu Chen, Jian Xu, Qiaomei He, Changmeng Zhang, Xiao Zhou, Xiaodan Ding, Jinan Fang, Fanlin Li, Ming Jiao, Yuqin Yang, Baoxia Dong, Liping Wan, Xueying Ding, Yan Zheng, Jingyi Zhou, Chijian Zuo, Tian Min, Ming Zhu, Bin Ma, Yuhua Wan, Qiufang Guo, Hua Zhang, Jian Hua, Pengran Wang, Qi Li, Jiang Long, Xianmin Song, Yan Zhang
BACKGROUND. Chronic alcohol use leads to synaptic dysfunction in preclinical studies. However, whether in vivo synaptic density deficits are found in people with alcohol use disorder (AUD) remains unclear. METHODS. Thirty-two people with AUD (17 women) and 29 controls (17 women) completed one positron emission tomography (PET) brain imaging scan with the radiotracer [11C]UCB-J, which binds to SV2A, a marker of synaptic density. Levels of synaptic density were quantified by estimating binding potential (BPND) across four regions of interest: frontal cortex, striatum, hippocampus, and cerebellum. RESULTS. People with AUD were on average(±SD) 43±13 years old and most met criteria for mild or moderate AUD. Controls were 37±12 years old. People with AUD had on average 11% lower [11C]UCB-J BPND than controls in the frontal cortex (F(1,62)=13.074, p<0.001), striatum (F(1,60)=10.283, p=0.002), hippocampus (F(1,60)=5.964, p=0.018), and trending in the same direction in cerebellum (F(1,50)=3.438, p=0.070). Among people with AUD, lower [11C]UCB-J BPND was significantly related to more drinks per drinking day in the frontal cortex (p=0.022) and striatum (p=0.026). People with AUD performed worse on executive function than controls (p=0.020), but this was not related to [11C]UCB-J BPND. CONCLUSION. Synaptic density deficits are evident, even in people with mild-to-moderate AUD, with greater deficits in those with greater drinking severity. These findings underscore the potential of synaptic restoration as a therapeutic target for AUD. TRIAL REGISTRATION. N/A. FUNDING. This work was supported by the National Institute of Health.
Yasmin Zakiniaeiz, Nakul R. Raval, Will Riordan, Nabeel Nabulsi, Yiyun Huang, Brian Pittman, David Matuskey, Gustavo A. Angarita, Robin Bonomi, Sherry A. McKee, Ansel T. Hillmer, Kelly P. Cosgrove
The lymphatic system maintains tissue fluid balance, and FOXC2 mutations cause lymphoedema-distichiasis syndrome, which is characterized by lymphatic valve defects. Although oscillatory shear stress regulates FOXC2 expression, other extracellular regulators remain unclear. In this study, we identified LPA4 and LPA6, two Gα12/Gα13-coupled receptors for the bioactive lipid lysophosphatidic acid (LPA), as key regulators of FOXC2 expression and lymphatic valve development. Lymphatic endothelial cell (LEC)-specific Lpa4;Lpa6-deficient mice exhibited impaired lymphatic valve formation and maintenance, which resembled phenotypes of LEC-specific Foxc2-deficient mice, including abnormal lymphatic vessel patterning. Mechanistically, lymphatic endothelial Lpa4/Lpa6 ablation reduced FOXC2 expression in vitro and in vivo. NF-κB was found essential for LPA-induced FOXC2 expression through the LPA4/LPA6-Gα12/Gα13-Rho kinase signaling axis. Accordingly, pharmacological inhibition of NF-κB and Rho kinase impaired lymphatic valve maintenance in mice. These results suggested that lymphatic endothelial LPA4 and LPA6 synergistically regulate FOXC2 expression through NF-κB activation and play an important role in lymphatic valve formation and maintenance. Our findings provide a molecular basis for lymphatic vessel development with a therapeutic potential for targeting lymphatic-associated diseases.
Daisuke Yasuda, Nana Sato, Keisuke Yanagida, Tomomi Hashidate-Yoshida, Tomohiro Shiiya, Hideo Shindou, Atsuki Taira, Takashi Ebihara, Takao Shimizu, Masanori Hirashima, Seiya Mizuno, Satoru Takahashi, Satoshi Ishii
Robert Corty, Yash Pershad, J. Brett Heimlich, Caitlyn Vlasschaert, Leo Luo, Taralynn Mack, Kaushik Amancherla, Cassianne Robinson-Cohen, Michael Savona, Alexander G. Bick
MRE11, a breast tumor suppressor and component of the MRE11-RAD50-NBS1 (MRN) complex, plays a critical role in DNA end resection and initiation of ATM-dependent DNA damage signaling. However, the precise mechanisms governing MRE11 function in the DNA damage response (DDR) remain incompletely understood. Here, we found that MRE11 is deacetylated by the SIRT2 sirtuin deacetylase and breast tumor suppressor, which promotes DNA binding to facilitate DNA end resection and ATM-dependent signaling. SIRT2 deacetylase activity promoted DNA end resection. SIRT2 further complexed with and deacetylated MRE11 at conserved lysine (K) 393 in response to DNA double-strand breaks (DSBs), which promoted MRE11 localization and DNA binding at DSBs but not interaction with RAD50, NBS1, or CtIP. Moreover, MRE11 K393 deacetylation by SIRT2 promoted ATM-dependent signaling. Our findings define a mechanism regulating MRE11 binding to DNA through SIRT2 deacetylation, elucidating a critical upstream signaling event directing MRE11 function in the DDR and providing insight into how SIRT2 dysregulation leads to genomic instability and tumorigenesis.
Fatmata Sesay, Hui Zhang, Priya Kapoor-Vazirani, Andrew T. Jung, Mark E. Essien, Amanda J. Bastien, Nho C. Luong, Xu Liu, PamelaSara E. Head, Duc M. Duong, Xiaofeng Yang, Zachary S. Buchwald, Xingming Deng, Nicholas T. Seyfried, David S. Yu
Large-cohort genome-wide association studies (GWAS) for alcohol use disorder (AUD) drug treatment outcomes and AUD risk have repeatedly identified genetic loci which are splicing quantitative trait loci for the fibronectin III domain containing 4 (FNDC4) gene in the brain. However, FNDC4 function in the brain and how it might contribute to AUD pathophysiology remain unclear. In the present study, we characterized GWAS loci-associated FNDC4 splice isoforms and demonstrated that FNDC4 alternative splicing results in loss-of-function for FNDC4. We also investigated FNDC4 function using CRISPR/cas9 editing, and the creation of human induced pluripotent stem cell (iPSC)-derived neural organoids joined with single-nucleus RNA sequencing, a series of studies which showed that FNDC4 knock-out (KO) resulted in a striking shift in the relative proportions of glutamatergic and GABAergic neurons in iPSC-derived forebrain organoids as well as changes in their electrical activity. We further explored potential mechanism(s) of FNDC4-dependent neurogenesis with results that suggested a role for FNDC4 in mediating neural cell surface interactions. In summary, this series of experiments indicates that FNDC4 plays a role in regulating cerebral cortical neurogenesis in the brain. This regulation may contribute to the response to AUD pharmacotherapy as well as the effects of alcohol on the brain.
Xiujuan Zhu, August J. John, Sooan Kim, Li Wang, Enci Ding, Jing Zheng, Ateka Saleh, Irene Marín-Goñi, Abedalrahman Jomaa, Huanyao Gao, Meijie Wang, Ching Man Wai, Irene Moon, Cindy Chen, Alireza Agahi, Brandon J. Coombes, Tony M. Kerr, Nobuyoshi Suto, Liewei Wang, Mark A. Frye, Joanna M. Biernacka, Victor M. Karpyak, Hu Li, Richard M. Weinshilboum, Duan Liu
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