Life Sciences Commons^™

Crosstalk Between Upr And Mitochondria: The Triad Of Er-Mitochondria Contacts, Ca²⁺, And Ros, Ester Zito, György Hajnóczky

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Endoplasmic reticulum (ER) stress is triggered by several cellular perturbations causing protein misfolding, and activates the unfolded protein response (UPR), an initially adaptive signaling network that aims to restore ER and cellular homeostasis. Growing evidence indicates that UPR signaling extends beyond ER proteostasis, influencing mitochondrial function and bioenergetics through ER-mitochondria contact sites (ERMCs). The CHOP-ERO1A-IP3R axis has a primary role in recruiting mitochondria to adaptive UPR. However, its sustained activation renders UPR signaling maladaptive, leading to mitochondrial dysfunction through both outer mitochondrial membrane permeabilization (OMMP) and mitochondrial permeability transition pore (mPTP) opening, ultimately contributing to irreversible cell injury and disease …

Mitochondrial Trna-Derived Fragments As Candidate Metastasis-Modifying Rna, Katy L. Swancutt, R. Mckinnon Walsh, Sydney Quijano, Emily Schueddig, Devin C. Koestler, Adam D. Scheid, Tony Vanden Bush, Yi Jing, Isidore Rigoutsos, Danny R. Welch

Computational Medicine Center Faculty Papers

UNLABELLED: How mitochondrial DNA (mtDNA) polymorphisms influence complex phenotypes remains poorly understood. Using mitochondrial-nuclear exchange mice, we previously showed that mtDNA single-nucleotide polymorphisms (SNP) modify metastasis, cardiovascular disease, and epigenetic marks independently of metabolic differences. The only mtDNA SNP correlating with these phenotypes resides in the gene encoding mitochondrial transfer RNA (tRNA)-arginine [mt-tRNAArg (UCG), mt-TR], suggesting a role for non-protein-coding loci. In this study, we identify and preliminarily characterize previously undescribed tRNA-derived fragments (tRF) generated from mt-TRs. Northern blotting revealed distinct tRF that are differentially expressed among mtDNA SNPs, between lung and liver, and between sexes. Surprisingly, small RNA sequencing …

Cells And Networks In Flux: Rethinking Ontogenesis And Pathogenesis, Mark L. Tykocinski

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Organ and tissue functions emerge from the coordinated activity of cell networks. Therapeutics that act on pathogenic cell networks, modulating their cellular interplay, follow naturally. Over several decades, our laboratory has developed a series of approaches for rewiring cell networks, culminating in a class of cell surface-directed signal converter proteins (SCPs) that do so by modulating juxtacrine and autocrine signaling in and among their nodal cells. A first such SCP has now produced encouraging clinical data for cancer immunotherapy. Yet, these early network-directed fusion proteins rest on a deliberately simplified picture: discrete end-cell types plugged into graphically tractable networks. That …

Hemodynamic Characterization Of Cardiac Dysfunction After Traumatic Brain Injury Using A Controlled Cortical Impact Model In Male Rats, Preston So, Amit Iyengar, Noah Weingarten, Mrinal Patel, Jessica Dominic, Andrew Belec, Joyce Ho, Samuel Shin, Pavan Atluri

Division of Cardiology Faculty Papers

Traumatic brain injury (TBI) is associated with cardiovascular dysfunction that worsens clinical outcomes, yet the underlying mechanisms are poorly under stood. Clinical studies are limited by heterogeneity, highlighting the need for con trolled experimental models. Controlled cortical impact (CCI) provides precise control of injury severity, and invasive pressure- volume (PV) loop analysis allows detailed hemodynamic assessment. Adult male Wistar rats underwent sham op eration or mild or severe CCI- induced TBI. PV- loop assessment and transtho racic echocardiography were performed at 8 or 24 h after TBI or sham. Serum epinephrine (EPI) and norepinephrine (NE) were quantified by ELISA. At …

Malt1 Protease Inhibition Restrains Glioblastoma Progression By Reversing Tumor-Associated Macrophage-Dependent Immunosuppression In Mice, Juliana Hofstätter Azambuja, Saigopalakrishna Yerneni, Lisa Maurer, Hannah Crentsil, Gabriela Debom, Linda Klei, Mei Smyers, Chaim Sneiderman, Kristina Schwab, Rajesh Acharya, Aivi Nguyen, Josie Emery, John Little, Jeffrey Meridew, Yijen Lin Wu, Prasanna Ekambaram, Dong Hu, Pete Gough, John Bertin, Ari Melnick, Gary Kohanbash, Riyue Bao, Peter Lucas, Linda Mcallister-Lucas

College of Life Sciences Faculty Papers

MALT1 protease is an intracellular signaling molecule that promotes tumor progression via cancer cell-intrinsic and cancer cell-extrinsic mechanisms. MALT1 has been mostly studied in lymphocytes, and little is known about its role in tumor-associated macrophages. We show that MALT1 is expressed in glioblastoma (GBM)-associated macrophages. Mechanistically, GBM tumor cells induce a MALT1-NF-κB signaling axis in macrophages, leading to enhanced macrophage migration and polarization toward an immunosuppressive ('M2-like') phenotype. Inactivation of MALT1 protease promotes transcriptional reprogramming that reduces migration and restores a macrophage anti-tumor 'M1-like' phenotype. Preclinical in vivo analysis shows that MALT1 inhibitor treatment results in immuno-reactivity of GBM-associated macrophages …

Nuclear Activities And Interactome Of The Ns5 Protein Of Tick-Borne Encephalitis Virus, Maxime Chazal, Aïssatou Aïcha Sow, Elodie Le Seac'h, Dana Hawasheen, Margarida Bonifacio, Mikael Feracci, Ségolène Gracias, Adrià Sogues, Melissa Molho, Heng Pan, Boris Bonaventure, Jean-Pierre Quivy, Geneviève Almouzni, Etienne Decroly, Holly Ramage, Jeffrey R. Johnson, Vincent Caval, Nolwenn Jouvenet

Department of Microbiology and Immunology Faculty Papers

Orthoflaviviruses are RNA viruses responsible for significant diseases in humans, domesticated animals, and wildlife. Their NS5 protein is central in viral replication, functioning both as an RNA-dependent RNA polymerase and a methyltransferase, while also modulating cellular processes, including the interferon response. Although viral replication is cytoplasmic, the NS5 protein of several mosquito-borne orthoflaviviruses cycles between the cytoplasm and the nucleus of infected human cells. However, the nuclear localization and function of NS5 of tick-borne orthoflaviviruses, such as tick-borne encephalitis virus (TBEV), remain poorly understood. Microscopy analysis and cell fractionation revealed that the NS5 protein of TBEV localized to both the …

Non-Enzymatic Hepatic Abhd6 Interacts With Akt-Foxo1 Axis To Regulate Metabolic Health, Guannan Li, Laurence T Maeyens, Jiyuan Yin, Jan-Bernd Funcke, Chanmin Joung, Ruizhen Li, Ziying Xu, Ting Wu, Xin Li, Nisi Jiang, Mbolle Ekane, Maria Paula Lopez, Pengju Cao, Sijia He, Adam B Salmon, S R Murthy Madiraju, Marc Prentki, Juli Bai, James F Nelson, Xianlin Han, Yi Zhu, Shangang Zhao

Children’s Nutrition Research Center Staff Publications

The enzymatic role of ABHD6 in insulin secretion and resistance is well documented. However, its non-enzymatic function, especially its effects on metabolic health, including selective hepatic insulin resistance and metabolic dysfunction-associated steatotic liver disease (MASLD), is poorly understood. To define the role of ABHD6 in liver physiology, we generated liver-specific ABHD6 knockout mice, as well as liver-specific native and enzymatically inactive mutant ABHD6 overexpression mouse models. We demonstrate that non-enzymatic ABHD6 contributes to the regulation of selective hepatic insulin resistance and MASLD progression. Mechanistically, we show that ABHD6 localizes to the nucleus and interacts with Akt/FoxO1 axis to regulate insulin …

Hyperadhesive Von Willebrand Factor Contributes To Pathogenesis Of Preeclampsia, Yajuan Wang, Chenyu Wang, Katie L Houck, Xiaoli Gao, Yuanyuan Chen, Xin Xu, Xue Zhao, Miguel A Cruz, Shu Zhang, Chester Q Li, Fengxia Xue, Min Li, Swati Shree, Jing-Fei Dong, Cha Han

Children’s Nutrition Research Center Staff Publications

Background: Preeclampsia is the most common complication of pregnancy, significantly affecting maternal and fetal health, and is characterized by placental and systemic endotheliopathy. Patients with preeclampsia have elevated levels of VWF (von Willebrand Factor), which is associated with poor clinical outcomes. However, whether VWF serves as a marker for endotheliopathy or contributes to the pathogenesis of preeclampsia remains poorly understood.

Methods: We investigated the role of hyperadhesive VWF in the development of preeclampsia by studying patients, evaluating mouse models, and performing in vitro experiments.

Results: We show that patients develop VWF- and fibrin-rich thrombosis in the placenta and have significantly …

De Novo Pyrimidine Synthesis Controls Germinal Center B Cell And Plasma Cell Fates And Systemic Autoimmunity, Julia L. Weber, Tien Bui, Keomonyroth Nuon, Adam J. Fike, Sophia M. Crocker, Kristen N. Bricker, Anju Maharjan, Wujuan Zhang, Aaron R. Goldman, Sathi Babu Chodisetti, Ziaur S. M. Rahman

Department of Microbiology and Immunology Faculty Papers

Whether and how pyrimidine metabolites promote systemic autoimmunity is unknown. Here, metabolomics and 15N-amide glutamine tracing show enhanced flux through de novo pyrimidine synthesis in systemic lupus erythematosus (SLE)-prone B cells. Temporal inhibition of pyrimidine synthesis dampens SLE-prone but not foreign antigen-specific germinal center (GC), plasma cell (PC), and antibody responses. Uridine monophosphate synthase (UMPS) conditional deletion, however, reveals a B cell-intrinsic requirement of de novo pyrimidine synthesis in foreign antigen-driven and SLE-prone GC, PC, and antibody responses and kidney immune complex deposition. Metabolomics, mitochondrial stress test, metabolic flow cytometry, glycolytic rate assay, and RNA sequencing highlight the importance of …

Proteogenomics Of Hypertrophic Cardiomyopathy Reveals Subtype-Specific Therapy, Ke Ma, Jie Yang, Hongchang Guo, Ping Li, Xiaowei Li, Zhujun Dong, Jing Zhang, Congcong Zhang, Pengli Yang, Chongpei Hua, Shuolin Zhu, Guoqing Li, Jianchao Zhang, Ningyu Ding, Jizheng Wang, Xin-Liang Ma, Zhuofeng Lin, Jianzeng Dong, Yang Li, Yulin Li

Department of Emergency Medicine Faculty Papers

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is a heterogeneous disease with diverse prognosis. The underlying mechanisms remain unknown, resulting in limited risk stratification and therapeutic strategies. This study aimed to elucidate molecular subtypes of HCM through integrated proteogenomic analysis and explore subtype-specific therapeutic strategies.

METHODS: We conducted an integrated proteogenomic analysis of 132 patients with HCM using myocardial samples, incorporating whole-exome sequencing, RNA sequencing, and proteomics. Unsupervised clustering was used to identify HCM subtypes, which were validated in heart tissues and human induced pluripotent stem cell-derived cardiomyocytes from 2 independent HCM subsets. Subtype-specific signatures and pathways were explored, and their causal link …

Crispr/Cas9-Based Genome Editing: Understanding Differences In Dna Repair Pathways, Profiles, And Outcomes, Samuel Effah, Shirley Barrera, Nahia Urturi Ortiz, Will Dampier, Michael Nonnemacher, Brian Wigdahl

Kimmel Cancer Center Faculty Papers

Over a decade of advances in Clustered Regularly Interspersed Short Palindromic Repeats (CRISPR) and CRISPR-associated protein 9 (Cas9)-based technologies have culminated in the first-ever FDA-approved CRISPR/Cas-based therapy. Aside from this approved therapy for sickle cell anemia, several CRISPR/Cas-based therapies are currently under development or testing for a range of chronic diseases, including viral diseases like human immunodeficiency virus type 1 (HIV-1) infection, genetic diseases like familial hypercholesterolemia, and cancer. The success of these therapies hinges on the effective delivery of CRISPR/Cas9 components to target regions, efficient Cas endonuclease editing, repair profiles generated, and their resulting outcomes. Here, we discuss the …

Intrathecal (G4c2)149 Delivery In C9orf72-Deficient Mice Yields Mild Motor Dysfunction And Als/Ftd Pathological Hallmarks, Katelyn Russell, Amelia Shahrabi, Suleyman Akerman, Matthew D. Byrne, Jeffrey Rothstein, Davide Trotti, Brigid Jensen, Aaron Haeusler

Farber Institute for Neuroscience Faculty Papers

A repeat expansion in C9ORF72 is the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), yet existing mouse models incompletely engage spinal regions implicated in disease. Here, an adeno-associated virus encoding (G4C2)149 repeats was delivered via neonatal intrathecal injection, achieving widespread CNS expression with robust spinal cord targeting. This approach was applied to mice with graded loss of endogenous C9orf72 to interrogate both gain- and loss-of-function mechanisms. Longitudinal motor, behavioral, and pathological analyses revealed that repeat expression primarily drives mild, progressive muscle weakness, whereas coordination deficits were largely genotype dependent. Subtle gait abnormalities and hyperactivity …

Hiv-1 Tat-Driven Glutamate Dysregulation: Implications For Cognitive Impairment In Hand, Brenna Duffy, Michael Nonnemacher, Sandhya Kortagere

Kimmel Cancer Center Faculty Papers

PURPOSE OF REVIEW: HIV-1-associated neurocognitive disorders (HAND) manifest in 15% to 50% of people with HIV, impairing learning and memory and executive function. The chronic generation of HIV-1 Transactivator of transcription (Tat) likely contributes to HAND via direct neuronal toxicity and glial-mediated toxicity. This review summarizes our current understanding of how chronic Tat generation from microglia and astrocytes promote glutamate excitotoxicity.

RECENT FINDINGS: In recent years, the indirect effects of Tat through the activation of glial cells have gained significant interest. This review highlights microglia and astrocytes as HIV-1 reservoirs that release Tat protein in the central nervous system. Specific …

High Mobility Group Motif Proteins’ Role In Fibrosis, Inflammation, And Vascular Injury In Systemic Sclerosis, Fabian A. Mendoza, Sonsoles Piera-Velazquez, Sergio A. Jimenez

Jefferson Institute of Molecular Medicine Papers and Presentations

Systemic Sclerosis (SSc) is an idiopathic systemic autoimmune disease characterized by progressive cutaneous and systemic fibrosis, severe vasculopathy, and multiple humoral and cellular immunological alterations. The pathogenesis of SSc is highly complex and remains incompletely elucidated. The fibrotic process is a crucial component of SSc and is responsible for organ failure and high mortality. Although an increasing understanding of the fibrotic process has enabled the clinical development of antifibrotic therapeutic agents, these agents have limited clinical efficacy. Recently, the potential role of a group of transcription factors containing a High Mobility Group (HMG) motif, in the development and pathological manifestations …

Decorin Promotes Nascent Proteoglycan Retention In Cartilage Matrix By Strengthening Collagen Ii-Aggrecan Integration, Thomas Li, Gabriela Canziani, Yuchen Liu, Neil Patel, Biao Han, Mingyue Fan, Annie Porter, Bryan Kwok, Chao Wang, Qing Li, David E. Birk, Renato V. Iozzo, Irwin M. Chaiken, X. Lucas Lu, Robert L. Mauck, Lin Han

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Cartilage extracellular matrix (ECM), a hydrated collagen II-aggrecan composite, undergoes dynamic turnover during both normal homeostasis and disease-associated remodeling. This study elucidates a crucial role for decorin in promoting the retention and stability of nascent aggrecan within this matrix. By applying bio-orthogonal click-labeling, we demonstrate that loss of decorin accelerates the release of nascent aggrecan under both physiological and inflammatory conditions, without affecting its preferential localization to the pericellular matrix. Conversely, supplementation with exogenous decorin mitigates inflammation-induced loss of nascent aggrecan, supporting its potential as a therapeutic target. At the molecular level, decorin exhibits strong binding affinity for aggrecan, and …

Chromatin Insulators Homie And Nhomie Can Interact With Distant Copies Either Together Or Separately, With Distinct Outcomes For Enhancer-Promoter Interactions, Miki Fujioka, Wenfan Ke, Paul Schedl, James B. Jaynes

Department of Biochemistry and Molecular Biology Faculty Papers

Chromatin insulators, a.k.a. boundary elements, separate regions of the chromosome with distinct chromatin characteristics, including distinct histone modifications. This activity affects gene expression by allowing chromatin domains to be stably regulated and maintained. Insulators also block enhancer-promoter interactions and, somewhat paradoxically, facilitate other interactions, particularly when they stitch together distant regions of the chromosome by pairing with specific partners. Here we explore how long-range interactions facilitated by insulator pairing are affected by the presence of two potentially competing partners. Our results show that when two partners are present, they can reduce each other's effects on distant gene expression, suggesting that …

Disease-Causing Mfn2 Mutants Impair Mitochondrial Fission Dynamics By Distinct Drp1 Dysregulation, Daniel Lagos, Pamela R. De Santiago, Nicolás Pérez-Bravo, Benjamín Cartes-Saavedra, Josefa Vial-Brizzi, Diego Troncoso-Chandía, Oliver Podmanicky, Rita Horvath, Verónica Eisner

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Mitochondria undergo fusion and fission. While DRP1 regulates fission, fusion is controlled by OPA1, MFN1, and MFN2. The balance between these processes and the crosstalk between machineries remains poorly understood. MFN2 mutations cause Charcot-Marie-Tooth disease type 2 A (CMT2A), affecting mitochondrial fusion and morphology. However, their role in fission is unclear. Using skin fibroblasts from CMT2A patients (L248H and M376V MFN2 mutations) and wild-type mouse embryonic fibroblasts expressing these variants, we studied how MFN2 mutations impact mitochondrial dynamics beyond fusion. We analyzed mitochondrial morphology and dynamics by live-cell confocal microscopy and tested fusion/fission protein levels, oxygen consumption rate (OCR), extracellular …

Loss Of Mct1 Mediated Lactate Uptake Causes Delayed Endplate Maturation And Intervertebral Disc Degeneration, Maria Tsingas, Konstantinos Tsingas, Mei Smyers, Wujuan Zhang, Aaron R. Goldman, Eulisa Lawrence, John A. Collins, Makarand V. Risbud

Department of Orthopaedic Surgery Faculty Papers

During skeletal growth, it is thought that the lactate secreted by the glycolytic nucleus pulposus (NP) cells exits the intervertebral disc into circulation via endplates. Our current studies challenge this long-held notion. Mice with early postnatal, endplate, and annulus fibrosus-specific deletion of lactate importer, MCT1, exhibited disc degeneration characterized by NP cell loss and pronounced endplate structural changes. Using metabolic and transcriptomic approaches, we demonstrate that MCT1 loss inhibits endplate chondrocyte differentiation and that lactate serves both as a crucial TCA metabolite and promotes protein and histone lactylation and gene expression. These findings suggest that during skeletal growth, NP-derived lactate …

Mitochondria-Er Contact Sites (Mercs) In The Cell Cycle: Molecular Architecture And Functional Remodeling Across Cellular States, Eduardo Silva-Pavez, Bruno Torres-Gonzalez, Michelle Sotomayor, Benjamín Cartes-Saavedra, Dorian V. Ziegler, Yessia Hidalgo-Fadic, Ulises Ahumada-Castro

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Mitochondria–endoplasmic reticulum (ER) contact sites (MERCS) are nanoscopic, dynamic platforms integrating metabolism, signaling, and stress responses to regulate cell fate. These nanoscopic interfaces remodel continuously to meet the demands of proliferating, quiescent, and senescent cells. We synthesize evidence that MERCS actively coordinate local Ca2+ signaling, non-vesicular lipid transfer, and proteostasis to shape mitochondrial function and cellular homeostasis. We discuss how MERCS architecture changes across the cell cycle and during arrest, distinguishing adaptive from maladaptive remodeling, and consider therapeutic potential in aging and age-related disease.

Crystal Structure Of Mouse Dxo In Complex With The Udp-N-Acetylglucosamine Cap And Molecular Mechanism For The Decapping Reactions, Najeeb Ullah, Selom K. Doamekpor, Liang Tong

Department of Biochemistry and Molecular Biology Faculty Papers

Noncanonical metabolite 5' caps have recently been identified on RNAs, and the DXO/Rai1 family of enzymes can remove these caps in eukaryotes. While the binding modes of NAD, FAD and dephospho-CoA (dpCoA) caps in the active site of mouse DXO have been determined, how DXO recognizes the UDP-glucose (UDP-Glc) and UDP-N-acetylglucosamine (UDP-GlcNAc) caps is not known. In addition, the molecular mechanism by which DXO catalyzes the decapping reactions is still poorly understood, especially the location of the water/hydroxide that attacks the scissile phosphate to initiate the decapping. Here we report the crystal structure of mouse DXO in complex with UDP-GlcNAc …

P300/Cbp Inhibition With Inobrodib In Combination With Gilteritinib And Venetoclax Targets Leukemia Stem Cells In Epigenetic Mutant Aml, Melanie L. Goetz, Jennifer S. Romer-Seibert, Amanda M. Versace, Scott Kogan, Chetan Jeurkar, Robert L. Bowman, Nigel Brooks, Kris Frese, Sara E. Meyer

Department of Pharmacology, Physiology, and Cancer Biology Faculty Papers

Acute myeloid leukemia (AML) is a fatal blood cancer with cytotoxic chemotherapy offering at best 25% 5-year survival. While targeted BCL2 and FLT3 inhibitors venetoclax and gilteritinib are used upfront in the treatment of a subset of adult patients with AML and help to extend the survival of some patients, a curative treatment combination with minimal side effects has yet to be discovered. We find that use of the dual histone acetyltransferase p300/CBP bromodomain inhibitor CCS1477 (inobrodib), together with venetoclax and gilteritinib, virtually eliminates leukemia stem cells in an aggressive preclinical model of DNMT3A/FLT3-mutant AML by impairing pro-oncogenic survival and …

Maternal Inflammation Alters Nuclear And Mitochondrial Dna Methylation Patterns In Neonatal Brain Monocytes, Andrew Ebenezer, Jonathan Hicks, Brooke Hollander, Alexander Hone, Mona Batish, Robert Akins, Adam Marsh, Elizabeth Wright-Jin

Department of Medicine Faculty Papers

Neonatal hypoxic ischemic encephalopathy (HIE) is a common birth complication that can cause death or lifelong disabling conditions like cerebral palsy, epilepsy, and autism. It is well established that maternal infection and inflammation are significant risk factors for HIE but reasons for this increase in neurological risk to the offspring remain unknown. Inflammation or infection are associated with epigenetic changes and may contribute to the increased risk of neurodevelopmental disability in exposed offspring. Here, we analyzed and compared DNA methylation patterns in brain monocytes isolated from control, maternal immune activation (MIA), and an inflammation sensitized HIE (IS-HIE) CF-1 mouse model …

A Multidomain Peptide Hydrogel-Liposome Composite For Controlled Release Of A Cyclic Dinucleotide In Oral Cancer, Joseph W R Swain, Andrea H Molina, Gemalene M Sunga, Danielle Chew-Martinez, Neeraja Dharmaraj, Alejandra Cobos Perez, Arghadip Dey, Ephraim J Vázquez-Rosado, Simon Young, Jeffrey D Hartgerink

Faculty, Staff and Student Publications

While immunotherapy is a promising treatment strategy for cancer, the majority of head and neck squamous cell carcinoma (HNSCC) patients treated with single-agent immunotherapy do not respond. Therefore, researchers are investigating combination treatments with immunostimulatory molecules that can maximize anti-tumor responses. Cyclic dinucleotides (CDNs) are STING agonists that hold promise in combination approaches, but they require frequent intratumoral administration when used in both preclinical models of HNSCC and clinical trials. To reduce administration frequency, we have created a peptide hydrogel–liposome composite system, K2-Lip(CDN), for local and prolonged availability of CDN. We investigated the loading limits of cationic liposomes in both …

Weaning Drives Microbiome-Mediated Epigenetic Regulation To Shape Immune Memory In Mice, Li Yang, Robert C Peery, Shirui Zhou, Xiaomin Chen, Leah M Farmer, Fabiola Gutierrez, Stephanie Fowler, Lanjing Zhang, Julia M Salamat, Karen Riggins, Jiejun Shi, Lanlan Shen

Children’s Nutrition Research Center Staff Publications

During weaning, the transition to solid food diversifies the gut microbiome, triggering a programmed immune response critical for long-lasting mucosal immunity. Previous work showed that the gut microbiome mediates epigenetic development in intestinal stem cells (ISCs) during suckling, but what happens during weaning is unclear. Here, genome-wide profiling revealed that weaning-driven microbiome changes shape the DNA methylome and transcriptome of murine ISCs in an IFNγ-dependent manner. Specifically, we observe demethylation of enhancer elements essential for MHC class II genes, which results in a transcriptional memory that persists through differentiation into adulthood. IFNγ blockade, or low-dose penicillin to target Gram-positive bacteria, …

Multiparametric Mri To Predict Response To Irreversible Electroporation Plus Anti-Pd-1 Immunotherapy In Pancreatic Ductal Adenocarcinoma, Qizhen Cao, Mark D Pagel, Charles V Kingsley, Jingfei Ma, James P Long, Xiaoxia Wen, Seth T Gammon, Jorge Delacerda, Sanaz Javadi, Chun Li

Faculty, Staff and Student Publications

Purpose: To investigate contrast-enhanced T1-weighted MRI and diffusion-weighted magnetic resonance imaging (DWI) for early prediction of tumor response to combined irreversible electroporation (IRE) and anti-PD-1 immunotherapy.

Methods: Murine pancreatic ductal adenocarcinoma (PDAC) cells KRAS* were inoculated into the pancreas of C57BL/6 mice. IRE was performed when tumors became palpable. After IRE, mice received six intraperitoneal injections of anti-PD-1 over 2 weeks. T2-weighted MRI, T1-weighted MRI with macromolecular contrast agent poly(L-glutamic acid)-conjugated gadolinium (PG-Gd), and DWI were performed before and after IRE. Survival was analyzed using Kaplan-Meier curves. Mice surviving at least 100 days without recurrence after IRE were considered complete …

Neutrophil-Microglia Interaction Drives Motor Dysfunction In A Neuromyelitis Optica Model Induced By Subarachnoid Aqp4-Igg, Fangfang Qi, Vanda A Lennon, Shunyi Zhao, Yong Guo, Husheng Ding, Caiyun Liu, Whitney M Bartley, Tingjun Chen, Claudia F Lucchinetti, Long-Jun Wu

Faculty, Staff and Student Publications

Neutrophils and neutrophil extracellular traps (NETs) contribute to early neuromyelitis optica (NMO) histopathology initiated by IgG targeting astrocytic aquaporin-4 (AQP4) water channels. Yet, the mechanisms underlying neutrophil recruitment and their pathogenic roles in disease progression remain unclear. To investigate molecular-cellular events preceding classical complement cascade activation in a mouse NMO model, we continuously infused, via spinal subarachnoid route, a non-complement-activating mouse monoclonal AQP4-IgG. Parenchymal infiltration of netting neutrophils containing C5a ensued with microglial activation and motor impairment but no blood-brain barrier leakage. Motor impairment and neuronal dysfunction both reversed when AQP4-IgG infusion stopped. Two-photon microscopy and electron microscopy-based reconstructions revealed …

Gompertz Growth With A Shared Carrying Capacity Optimally Simulates Primary And Metastatic Tumor Growth Dynamics, Pirmin Schlicke, Preethi Korangath, Xiaoxi Pan, Caner Ercan, Kathleen Gabrielson, Lyndsey Werhane, Yinyin Yuan, Sébastien Benzekry, Robert Ivkov, Heiko Enderling

Faculty, Staff and Student Publications

Background: Cancer is a systemic disease with most deaths attributed to metastatic burden. Primary and metastatic tumors, albeit at different anatomic locations, are interconnected through multiple biological processes. Pre-clinical and clinical observations of growth acceleration of metastases after surgery, or abscopal effects outside the radiation field are widely reported, yet reliably triggering favorable and avoiding unfavorable systemic responses remains an unmet clinical need. Understanding local and systemic tumor interaction dynamics will help guide future treatments.

Methods: We analyze the data of multiple in vivo tumor models. We formalize the systemic interplay of tumors as mathematical differential equation and calibrate parameters …

Structural-Functional Analyses Of The Huntingtin/Hap40 Complex In Drosophila And Humans, Stephen M Farmer, Amanda Solbach, Shiyu Xu, Beatriz Rios, Xin Ye, Amy Gao, Daniela Covarrubias, Yue Yu, Lili Ye, Vicky Chuong, Erin Furr Stimming, Haiqing Zhao, Sheng Zhang

Faculty, Staff and Student Publications

Huntington's disease (HD) is a neurodegenerative disorder caused by an abnormal CAG expansion in the Huntingtin (HTT) gene. Given its simple genetic cause but complex pathogenic mechanisms, interest in targeting HTT for HD treatment is growing, necessitating a clear understanding of HTT regulation. HTT protein primarily exists in a core complex with HAP40, forming a highly ordered structure with two large globular domains connected by a bridge. We previously demonstrated that HAP40 is conserved in

Synthetic Lethality Between Rb-Loss And E2f3 Inhibition In Small Cell Cancers Targeted By Pyrimidine Synthesis Blockade, Evan R. Abt, Liang Wang, Grigor Varuzhanyan, Jack Freeland, Tian He, Guadalupe M. Peña-Garcia, Lauryn Ruegg, Jami Mclaughlin, Donghui Cheng, Nikolas G. Balanis, Chia-Chun Chen, Yang Xu, Yi Xing, Sanaz Memarzadeh, Caius G. Radu, Thomas G. Graeber, Owen N. Witte

Department of Pharmacology, Physiology, and Cancer Biology Faculty Papers

Small cell carcinoma is a highly lethal cancer variant often found with neuroendocrine (NE) features, as exemplified by small cell lung cancer and small cell NE prostate cancer (SCPC). A genome-wide CRISPR dependency screen using SCPC models generated through human prostate cell transformation identifies a requirement for the transcription factor E2F3. E2F3 dependency is linked to RB inactivation, a near universal occurrence across small cell cancers. The requirement for E2F3 is shared by RB-deficient cells originating from the prostate, lung, and adnexa. In RB-deficient cancer cells, E2F3 inhibition restrains cell cycle progression, proliferation, and tumor growth in vivo. Inhibition of …

Polθ Activity Modulates Sensitivity To Standard Therapies In Dnmt3a-Deficient Leukemia, Bac Viet Le, Umeshkumar Vekariya, Monika M. Toma, Margaret Nieborowska-Skorska, Marie-Christine Caron, Malgorzata Gozdecka, Zayd Haydar, Martin Walsh, Jayashri Ghosh, Elaine Vaughan-Williams, Paulina Podszywalow-Bartnicka, Anna-Mariya Kukuyan, Sylwia Ziolkowska, Jessica Atkins, Emir Hadzijusufovic, Gurushankar Chandramouly, Reza Nejati, Katarzyna Piwocka, Richard T. Pomerantz, George S. Vassiliou, Brian J.P. Huntly, Peter Valent, Mariusz Wasik, Alfonso Bellacosa, Jean-Yves Masson, Gaorav P. Gupta, Grant A. Challen, Tomasz Skorski

Department of Biochemistry and Molecular Biology Faculty Papers

Myeloid malignancies carrying somatic DNMT3A mutations (DNMT3Amut) are refractory to standard therapy. DNMT3Amut leukemia cells accumulate toxic DNA double-strand breaks (DSBs) and stalled replication forks, rendering them dependent on DNA damage response (DDR). We report here that DNA polymerase theta (Polθ), a key element in DSB repair by end-joining (Polθ-mediated end-joining [TMEJ]) and in fork restarting, promotes survival and proliferation of DNMT3Amut leukemia cells. Polθ is overexpressed in DNMT3Amut leukemia cells due to abrogation of PARP1 PARylation-dependent UBE2O E3 ligase-mediated ubiquitination and proteasomal degradation of Polθ. In addition, PARP1-mediated recruitment of the SMARCAD1-MSH2/MSH3 repressive complex to DSBs is diminished in …