Medical Specialties Commons^™

Tng260 Is A Small-Molecule Corest Inhibitor That Sensitizes Stk11-Mutant Tumors To Anti-Pd-1 Immunotherapy, Leanne G Ahronian, Soumyadip Sahu, Minjie Zhang, Ayushi S Patel, Ke Geng, Reshmee Bhattacharya, Gerald S Falchook, Jonathan W Goldman, Alexander I Spira, Salman R Punekar, David R Spigel, Judy S Wang, Ferdinandos Skoulidis, Janaye Stephens, Mary Meynardie, Jaylen M Powell, Alfonso Lopez, Michela Ranieri, Magdalena A Ploszaj, Yi Jer Tan, Yeuan Ting Lee, Yi Yu, Jiehui Deng, Ting Chen, Patrick Mccarren, Alice Tsai, Suleman S Hussain, Brian Doyon, Kenjie Amemiya, Jacques Ermolieff, Preksha Shahagadkar, Nikitha M Das, Lauren R Flynn, Julie A Shields, Laney Danielczyk, Brian J Mcmillan, Andre Mignault, Samuel R Meier, Hsin-Jung Wu, David J Guerin, Douglas A Whittington, Chengyin Min, Iga Sienczylo, John P Maxwell, Heather J Dibenedetto, Hideo Watanabe, Brian B Haines, Alan Huang, Adam Crystal, Jannik N Andersen, Xinyuan Wu, Kwok-Kin Wong

Faculty, Staff and Student Publications

Patients with non–small cell lung cancer (NSCLC) with loss of the tumor suppressor gene STK11 are resistant to immune checkpoint therapies like anti–PD-1. In this study, we conducted an in vivo CRISPR screen that identified histone deacetylase 1 as a target to reverse anti–PD-1 resistance driven by loss of STK11 and developed TNG260, a potent small-molecule inhibitor of the CoREST complex with selectivity exceeding previously generated inhibitors in this class in preclinical studies. Treatment with TNG260 led to increased expression of immunomodulatory genes in STK11-deficient cancer cells. When combined with anti–PD-1, TNG260 induced immune-mediated stasis and/or regression in STK11 …

Resilience And Vulnerabilities Of Tumor Cells Under Purine Shortage Stress, Jianpeng Yu, Chen Jin, Cheng Su, David Moon, Michael A Sun, Hong Zhang, Xue Jiang, Fan Zhang, Nomi Tserentsoodol, Michelle L Bowie, Christopher J Pirozzi, Daniel J George, Robert Wild, Xia Gao, David M Ashley, Yiping He, Jiaoti Huang

Faculty, Staff and Students Publications

Purpose: Purine metabolism is a promising therapeutic target in cancer; however, how cancer cells respond to purine shortage, particularly their adaptation and vulnerabilities, remains unclear.

Experimental design: Using the recently developed purine shortage-inducing prodrug DRP-104 and genetic approaches, we investigated the responses in prostate, lung, and glioma cancer models.

Results: We demonstrate that when de novo purine biosynthesis is compromised, cancer cells employ microtubules to assemble purinosomes, multiprotein complexes of de novo purine biosynthesis enzymes that enhance purine biosynthesis efficiency. Although this process enables tumor cells to adapt to purine shortage stress, it also renders them more susceptible to the …

Yx0798 Is A Highly Potent, Selective, And Orally Effective Cdk9 Inhibitor For Treating Aggressive Lymphoma, Vivian Jiang, Yu Xue, Hong Kim, Qingsong Cai, Tianci Zhang, Lei Nie, Joseph Mcintosh, Yang Liu, Haiying Chen, Jia Zhou, Michael Wang

Faculty, Staff and Student Publications

Nongenetic transcription evolution has been increasingly explored and recognized to drive tumor cell progression and therapeutic resistance. As the regulation hub of transcription machinery, cyclin-dependent kinase 9 (CDK9) is the gatekeeper of RNA polymerase II transcription, and CDK9 dysfunction results in transcriptomic reprogramming and tumor cell progression. We recently reported that the heat shock protein 90 (HSP90)-MYC-CDK9 network drives therapeutic resistance in mantle cell lymphoma (MCL) through transcriptomic reprogramming. We also showed that targeting CDK9 by AZD4573 and enitociclib is a safe and effective treatment in preclinical Mantle Cell Lymphoma (MCL) models, supporting CDK9 as a valid therapeutic target for …

Inhibition Of Osteosarcoma Lung Metastases By Β-Glucan And Cd40 Agonist Is Mediated By Activation Of Macrophages And Nk Cells, Pradeep Shrestha, Rejeena Shrestha, Eugenie S Kleinerman

Faculty, Staff and Student Publications

Background: Osteosarcoma (OS) lung metastases remain a significant therapeutic challenge. Innate immune activation is a promising therapeutic approach. Innate immune agonists can modulate the tumor immune microenvironment and improve therapeutic response.

Methods: Using an experimental syngeneic OS lung metastasis BALB/c mouse model with K7M3-luc OS cells, we evaluated the antitumor effects of yeast-derived particulate β-glucan in prevention and therapeutic settings. We then assessed whether the CD40 agonist (CD40a) in combination with β-glucan increased therapeutic response in two different immune-competent mouse models of OS lung tumor burden.

Results: In the pretreatment settings, mice treated with β-glucan prior to OS cell infusion …

Polychlorinated Biphenyls Alter Estrogen Receptor Β-Mediated Epigenetic Regulation, Promoting Endometriosis, Yuri Park, Nuri Sung, Eunsu Kim, Jaeyeong Jeong, Juhee Sim, Mi Jin Park, John P Lydon, Xiaoming Guan, Sang Jun Han

Faculty, Staff and Students Publications

Endometriosis is a pathological condition characterized by the ectopic growth of endometrial cells, leading to chronic pelvic pain and infertility. Epidemiological studies have associated exposure to dioxin-like polychlorinated biphenyls, particularly PCB126, with an increased risk of endometriosis. However, the underlying mechanisms of this association remain poorly understood. We utilized a surgically induced endometriosis mouse model and human endometrial cell lines to assess the impact of PCB126 on endometriosis progression. Mice were exposed to environmentally relevant doses of PCB126. Endometriotic lesion growth, estrogen receptor signaling, receptor tyrosine kinase activity, and gene expression changes induced by PCB126-mediated elevation of DNA methyltransferase 3A …

Comprehensive Analysis Of The Tumor Targeting Efficiency Of Functionalized Nanoparticles In An Immunocompetent Environment, Nolan Jackson, Nasry Bouzeineddine, Daniel Cecchi, Safara Holder, Katrina Gee, Wayne Beckham, Sameh Basta, Sunil Krishnan, Devika B Chithrani

Faculty, Staff and Student Publications

The success of nanoparticle-based cancer therapeutics relies on their efficient tumor uptake and retention. Given this, improving nanoparticle localization in tumors is paramount to maximize their therapeutic potential. A common approach to achieve this is to functionalize nanoparticles with active targeting moieties that bind to specific tumor-associated receptors. Among these, arginine-glycine-aspartic acid (RGD) peptides have shown a potential to promote tumor accumulation by targeting the ανβ3 integrin receptor, a receptor commonly overexpressed by tumors owing to its role in promoting angiogenesis, metastasis and proliferation. Yet, its efficacy is commonly assessed using immunocompromised mice models. While useful, these models do not …

Dual Targeting Of Orphan Nuclear Receptors Nr4a1 And Nr4a2 For Nonhormonal Endometriosis Therapy, Wai Ning Tiffany Tsui, Yuri Park, Srijana Upadhyay, Da Mi Kim, Lei Zhang, Gus Wright, Amanuel Hailemariam, Arafat Rahman Oany, Sang Jun Han, Stephen Safe

Faculty, Staff and Students Publications

Previous studies show that orphan nuclear receptor 4A1 (NR4A1) regulates endometriotic cell growth, survival, estrogen receptor β (ERβ), mechanistic target of rapamycin signaling and fibrosis. NR4A2 is also expressed in epithelial and stromal derived endometriotic cells, and in this study the effects of 1,1-bis(3'-indolyl)-(3,5-disubstitutedphenyl)methane (DIM-3,5) dual NR4A1/nuclear receptor 4A2 (NR4A2) ligands and knockdown of NR4A1 and NR4A2 were investigated. The dual NR4A1/2 DIM-3,5 analogs inhibited previously identified proendometriotic pathways and gene products, and they also inhibited TWIST1 and multiple markers associated with epithelial-to-mesenchymal transition (EMT). The results show that both NR4A1 and NR4A2 regulate the same pathways, including endometriotic cell …

Quiescent Oxphos-High Triple-Negative Breast Cancer Cells That Persist After Chemotherapy Depend On Bcl-Xl For Survival, Slawomir Andrzejewski, Marie Winter, Leandro Encarnacao Garcia, Olusiji Akinrinmade, Francisco Madeira Marques, Emmanouil Zacharioudakis, Anna Skwarska, Julio Aguirre-Ghiso, Marina Konopleva, Guangrong Zheng, Susan A Fineberg, Daohong Zhou, Evripidis Gavathiotis, Tao Wang, Eugen Dhimolea

Faculty, Staff and Student Publications

The persistent residual tumor cells that survive after chemotherapy are a major cause of treatment failure, but their survival mechanisms remain largely elusive. These cancer cells are typically characterized by a quiescent state with suppressed activity of MYC and MTOR. We observed that the MYC-suppressed persistent triple-negative breast cancer (TNBC) cells are metabolically flexible and can upregulate mitochondrial oxidative phosphorylation (OXPHOS) genes and respiratory function ("OXPHOS-high" cell state) in response to DNA-damaging anthracyclines such as doxorubicin, but not to taxanes. The elevated biomass and respiratory function of mitochondria in OXPHOS-high persistent cancer cells were associated with mitochondrial elongation and remodeling, …

Synaptic Transmission Promotes Brain Metastatic Outgrowth In Breast Cancer, Jayanta Mondal, Patrick Nylund, Prit Benny Malgulwar, William E Johnson, Jason T Huse

Faculty, Staff and Student Publications

This work demonstrates that normal neuron-to-neuron signaling machinery is hijacked by metastasizing cancer cells during their outgrowth in the central nervous system.

Biliverdin Reductase A Is A Major Determinant Of Protective Nrf2 Signaling, Chirag Vasavda, Ruchita Kothari, Navneet Ammal Kaidery, Suwarna Chakraborty, Sunil Jamuna Tripathi, Ryan S Dhindsa, Cristina Ricco, Shruthi Shanmukha, Samaneh Saberi, Julia E Lefler, Priyanka Kothari, Kalyani Chaubey, Adele M Snowman, Michael C Ostrowski, Eugenio Barone, Lakshminarayan M Iyer, L Aravind, Sudarshana M Sharma, Andrew A Pieper, Bobby Thomas, Solomon H Snyder, Bindu D Paul

Duncan NRI Faculty and Staff Publications

Biliverdin reductase A (BVRA), the terminal enzyme in heme catabolism, generates the neuroprotective and lipophilic antioxidant bilirubin. Here, we identify a nonenzymatic role for BVRA in redox regulation. Through phylogenetic, genetic, biochemical, and enzymatic assays, we found that BVRA exerts critical nonenzymatic antioxidant activity. Transcriptomic analyses further revealed that BVRA physically and genetically interacts with nuclear factor erythroid-derived factor-like 2 (NRF2), a major transcriptional regulator of cellular redox signaling. ChIP-seq and RNA-seq analyses reveal that BVRA and NRF2 coordinate the expression of antioxidant genes, many of which are typically dysregulated in neurodegenerative conditions such as Alzheimer's disease. Thus, this noncanonical …

Enhanced Piezo1 Function Contributes To The Pathogenesis Of Sickle Cell Disease, Luis O Romero, Manisha Bade, Laila Elsherif, Jada D Williams, Xiangmei Kong, Adebowale Adebiyi, Kenneth I Ataga, Shang Ma, Julio F Cordero-Morales, Valeria Vásquez

Faculty, Staff and Student Publications

Sickle cell disease (SCD), an inherited blood disorder caused by a mutation in the β-globin gene, is characterized by sickle erythrocytes that are prone to hemolysis, leading to anemia and vaso-occlusion crises. In sickle erythrocytes, hemoglobin aggregation is followed by altered cation permeability and subsequent dehydration. Interventions that restore cation permeability can decrease hemolysis and ameliorate the symptoms associated with SCD. PIEZO1 is a nonselective mechanosensitive cation channel that regulates erythrocyte volume. Gain-of-function (GOF) mutations in PIEZO1 cause hemolytic anemia by increasing cation permeability, leading to erythrocyte dehydration in humans and mice. Although PIEZO1 plays a key role in erythrocyte …

Multicenter Stroke Preclinical Assessment Network Analysis Of Cardiovascular Risk Factor Subgroups Treated With The Poly(Adp-Ribose) Polymerase Inhibitor Veliparib, Raymond C Koehler, Karni Bedirian, Mu-Hsun Chen, Yanrong Shi, Suyi Cao, Brooklyn D Avery, Senthilkumar S Karuppagounder, Kazi Akhter, Adnan Bibic, Valina L Dawson, Ted M Dawson, Márcio A Diniz, Jessica Lamb, Karisma A Nagarkatti, Anjali Chauhan, Jaroslaw Aronowski, Louise D Mccullough, Andreia Lopes De Morais, Xuyan Jin, Cenk Ayata, Mariia Kumskova, Rakesh B Patel, Anil K Chauhan, Enrique C Leira, Pradip K Kamat, Mohammad B Khan, Krishnan M Dhandapani, David C Hess, Ligia S B Boisserand, Basavaraju G Sanganahalli, Lauren H Sansing, Patrick D Lyden

Faculty, Staff and Student Publications

Background: The Stroke Preclinical Assessment Network tested 6 therapeutic interventions initiated at the time of reperfusion after focal ischemic stroke in young mice, aging mice, obese mice, and spontaneously hypertensive rats. This randomized, controlled trial was conducted across 6 sites with concealed treatment and blinded neurobehavior assessments. The trial had an adaptive design with preset levels of efficacy and futility interrogated after each of 4 stages. The primary outcome was turning preference on the corner test at 1 month. The PARP (poly(ADP-ribose) polymerase) inhibitor, veliparib, was considered futile after the second stage when pooling all animal models (n=231 …

Phosphorylation Of Ryr1 At Ser2902 Decreases Ca2+ Leak In Skeletal Muscle And Susceptibility To Malignant Hyperthermia And Heat Stroke, Rachel Sue Zhen Yee, Chang Seok Lee, Ting Chang, Sung Yun Jung, Omar Yousif, Courtney Cavazos, John Colyer, Filip Van Petegem, George G Rodney, Susan L Hamilton

Faculty, Staff and Students Publications

The ryanodine receptor 1 (RYR1) is the sarcoplasmic reticulum (SR) Ca2+ release channel required for both skeletal muscle contraction and Ca2+ leak. Mutations in RYR1 cause malignant hyperthermia susceptibility (MHS) and enhanced sensitivity to heat stroke (ESHS), which can result in death due to excessive skeletal muscle thermogenesis upon exposure to volatile anesthetics or heat. Here, we investigated the molecular and physiological functions of phosphorylation of RYR1 at Ser2902 by the kinase SPEG (striated muscle preferentially expressed protein). Muscle from SPEG-deficient mice expressing RYR1 with a Ser2902 →Asp2902 (S2902D) point mutation to mimic phosphorylation by SPEG showed decreased SR Ca2+ …

Atg Conjugation-Dependent/Independent Mechanisms Underlie Lysosomal Stress-Induced Tfeb Regulation, Shiori Akayama, Takayuki Shima, Tatsuya Kaminishi, Mengying Cui, Jlenia Monfregola, Kohei Nishino, Andrea Ballabio, Hidetaka Kosako, Tamotsu Yoshimori, Shuhei Nakamura

Duncan NRI Faculty and Staff Publications

TFEB, a master regulator of autophagy and lysosomal biogenesis, is activated by several cellular stresses including lysosomal damage, but its underlying mechanism is unclear. TFEB activation during lysosomal damage depends on the ATG conjugation system, which mediates lipidation of ATG8 proteins. Here, we newly identify ATG conjugation-independent TFEB regulation that precedes ATG conjugation-dependent regulation, designated Modes I and II, respectively. We reveal unique regulators of TFEB in each mode: APEX1 in Mode I and CCT7 and/or TRIP6 in Mode II. APEX1 interacts with TFEB independently of the ATG conjugation system, and is required for TFEB stability, while both CCT7 and …

Atg16l1 Controls Mammalian Vacuolar Proton Atpase, Thabata L A Duque, Masroor Paddar, Einar Trosdal, Ruheena Javed, Lee Allers, Michal H Mudd, Prithvi Akepati, Soumya R Mishra, Michelle Salemi, Brett Phinney, Shawn B Bratton, Thomas Wileman, Vojo Deretic

Faculty, Staff and Student Publications

The mechanisms governing mammalian proton pump V-ATPase function are of fundamental and medical interest. The assembly and disassembly of cytoplasmic V1 domain with the membrane-embedded V0 domain of V-ATPase is a key aspect of V-ATPase localization and function. Here, we show that the mammalian protein ATG16L1, primarily appreciated for its role in canonical autophagy and in noncanonical membrane atg8ylation processes, controls V-ATPase. ATG16L1 knockout elevated V-ATPase activity, increased V1 presence on endomembranes, and increased the number of acidified intracellular compartments. ATG16L1's ability to efficiently bind V-ATPase was required for its inhibitory role in endolysosomal acidification and for control of Mycobacterium …

All-Optical Voltage Interrogation For Probing Synaptic Plasticity In Vivo, Jacques Carolan, Michelle A Land, Xiaoyu Lu, Maxime Beau, Dimitar Kostadinov, François St-Pierre, Beverley A Clark, Michael Häusser

Faculty, Staff and Students Publications

Measuring synaptic efficacy and defining the rules for induction of synaptic plasticity at identified connections in the mammalian brain is essential for understanding how synapses contribute to learning and memory. This requires new approaches to selectively evoke presynaptic activity and measure postsynaptic responses with high spatiotemporal resolution and high sensitivity over long periods in vivo. Here we develop an all-optical approach to probe synaptic plasticity at identified cerebellar synapses in awake, behaving mice. We developed and applied JEDI-2Psub, a genetically encoded voltage indicator with increased sensitivity around resting membrane potentials, to record subthreshold and suprathreshold activity in Purkinje cell (PC) …

Preclinical Models Of Melanoma Leptomeningeal Disease To Assess Intrathecal Checkpoint Blockade, Renato A Guerrieri, Grant M Fischer, Jacob R Cortez, Barbara G Knighton, Debora A Ledesma, Courtney W Hudgens, Yimmy F Delcid, Qianghua Hu, Christian Y B Onana, Fernando C L Carapeto, Michael T Tezlaff, Jason T Huse, Patrick Hwu, Elizabeth M Burton, Isabella C Glitza Oliva, Michael A Davies, Sherise D Ferguson

Faculty, Staff and Student Publications

Leptomeningeal disease (LMD) is a subtype of central nervous system metastatic disease that is associated with poor patient outcomes and limited treatment options. There is an unmet need to develop preclinical models of LMD to expedite and improve the development of new therapeutics. Here, we describe the development of multiple orthotopic immunocompetent murine models of melanoma LMD, including their use to assess the efficacy of systemic and/or intrathecal immunotherapy. LMD was established by direct intrathecal injection of murine cell lines (B16-F10, BP, D4M, D4M-UV2, MC38-gp100, RMS, YUMM3.1, and YUMMER1.7) into the cisterna magna of C57BL/6 mice. Tumor take rate, distribution, …

A Mast Cell Receptor Mediates Post-Stroke Brain Inflammation Via A Dural-Brain Axis, Ruchita Kothari, Mostafa W Abdulrahim, Hyun Jong Oh, Daniel H Capuzzi, Collin B Kilgore, Sumil K Nair, Yaowu Zhang, Nathachit Limjunyawong, Sarbjit S Saini, Jennifer E Kim, Justin M Caplan, Fernanado L Gonzalez, Christopher M Jackson, Chetan Bettegowda, Judy Huang, Bhanu P Ganesh, Chunfeng Tan, Raymond C Koehler, Rafael J Tamargo, Louise D Mccullough, Risheng Xu, Xinzhong Dong

Faculty, Staff and Student Publications

The immune environment surrounding the brain plays a fundamental role in monitoring signs of injury. Insults, including ischemic stroke, can disrupt this balance and incite an exaggerated inflammatory response, yet the underlying mechanism remains unclear. Here, we show that the mast-cell-specific receptor Mrgprb2 regulates post-stroke brain inflammation from the meninges. Mrgprb2 causes meningeal mast cell degranulation after stroke, releasing immune mediators. This process recruits skull bone marrow neutrophils into the dura and further promotes neutrophil migration from the dura into the brain by cleaving the chemorepellent semaphorin 3a. We demonstrate that the human ortholog, MRGPRX2, is expressed in human meningeal …

Escape Of Kdm6a From X Chromosome Is Detrimental To Ischemic Brains Via Irf5 Signaling, Conelius Ngwa, Afzal Misrani, Kanaka Valli Manyam, Yan Xu, Shaohua Qi, Romana Sharmeen, Juneyoung Lee, Long-Jun Wu, Louise Mccullough, Fudong Liu

The Brown Foundation: Institute of Molecular Medicine

The role of chromatin biology and epigenetics in disease progression is gaining increasing recognition. Genes that escape X chromosome inactivation (XCI) can impact neuroinflammation through epigenetic mechanisms. Our previous study has suggested that the X escapee genes Kdm6a and Kdm5c are involved in microglial activation after stroke in aged mice. However, the underlying mechanisms remain unclear. We hypothesized that Kdm6a/5c demethylate H3K27Me3/H3K4Me3 in microglia, respectively, and mediate the transcription of interferon regulatory factor 5 (IRF5) and IRF4, leading to microglial pro-inflammatory responses and exacerbated stroke injury. Aged (17–20 months) Kdm6a/5c microglial conditional knockout (CKO) female mice (one allele of the …

Endoglin-Directed Car T Cells Comprehensively Target Tumors In Advanced Sarcomas, Harrison R Berger, Malina Maharana, Jeneffer Mirabal, Lyazat Kurenbekova, Alberto Delaidelli, Atreyi Dasgupta, Ahmed Z Gad, Mohamed F Sheha, Sybrina S Kerr, Ada I Ozcan, Jessica S Morris, Angela M Major, M John Hicks, Mary K Mckenna, Ben K Seon, Matthew L Baker, Poul H Sorensen, Meenakshi Hegde, Jason T Yustein, Nabil Ahmed, Sujith K Joseph

Faculty, Staff and Students Publications

There are limited therapeutic options for patients with advanced sarcomas, which leads to dismal outcomes for children and adults. Although chimeric antigen receptor (CAR) T cells hold promise for treating advanced sarcomas, this approach is constrained by a paucity of effective targets. Our previous clinical study identified endoglin (ENG/CD105), a TGFβ coreceptor, as a target of the endogenous immune response in a patient with sarcoma who exhibited an exceptional response to HER2-targeted CAR T-cell therapy. ENG is expressed on various sarcomas, cancer-associated fibroblasts, and neoangiogenic vessels and therefore offers comprehensive tumor targeting. Furthermore, ENG knockout in sarcoma cells reduces their …

Protein Kinase Rock1 Activates Mitochondrial Fission Linking To Oxidative Stress And Muscle Atrophy, Meijun Si, Jihong Chen, Rizhen Yu, Hongchun Lin, Feng Li, Sungyun Jung, Sandhya S Thomas, Farhard R Danesh, Yanlin Wang, Hui Peng, Zhaoyong Hu

Faculty, Staff and Students Publications

Introduction: Chronic kidney disease (CKD) is associated with protein-energy wasting, characterized by a reduction in muscle mass and strength. Although mitochondrial dysfunction and oxidative stress are implicated in the pathogenesis of muscle wasting, underlying mechanisms remain unclear.

Methods: Here, we used transcriptomic analysis, metabolomics analyses, and mouse gene manipulation to investigate the effects of mitochondrial plasticity and oxidative stress on muscle wasting the subtotal nephrectomy mouse models of CKD. The mice with CKD were age- and sex-matched to sham-operated controls.

Results: Through these approaches, Rho-associated kinase ROCK1 emerged as a key molecule responsible for the observed mitochondrial fission and oxidative …

Phosphorylation At Serine 214 Correlates With Tau Seeding Activity In An Age-Dependent Manner In Two Mouse Models For Tauopathies And Is Required For Tau Transsynaptic Propagation, Pablo Martinez, Nur Jury-Garfe, Henika Patel, Yanwen You, Abigail Perkins, Yingjian You, Audrey Lee-Gosselin, Ruben Vidal, Cristian A Lasagna-Reeves

Faculty, Staff and Students Publications

Background

Tau aggregation and propagation are hallmark features of Alzheimer's disease and related tauopathies. The molecular identity and post-translational modifications that contribute to tau seeding activity remain incompletely understood.

Objective

To characterize the temporal dynamics of tau seeding activity and identify specific phosphorylated tau species associated with tau propagation in vivo.

Methods

We profiled tau seeding activity using a FRET-based biosensor cell line and correlated it with the abundance of phospho- and conformational tau species in two transgenic mouse models of tauopathy (P301S-1N4R and P301S-0N4R). Immunohistochemistry and subcellular fractionation were used to examine the spatial distribution of tau species. Functional …

Tigit Affects Car Nk-Cell Effector Function In The Solid Tumor Microenvironment By Modulating Immune Synapse Strength, Ishwar Navin, Matthew Dysthe, Prashant S Menon, Corrine Baumgartner, Tim Sauer, Navin Varadarajan, Robin Parihar

Faculty, Staff and Students Publications

Therapies using NK cells that express chimeric antigen receptors (CAR-NK) have been successfully employed against hematologic malignancies. However, solid tumors resist CAR-NKs partly by enriching tumor microenvironments with ligands for NK cell inhibitory receptors. Although the NK inhibitory receptor T-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain (TIGIT) has been implicated in impaired antitumor activity of endogenous NK cells, the consequences of TIGIT expression on engineered CAR-NKs have not been explored. To address this gap, we compared TIGIT-expressing and TIGIT-deleted human CAR-NKs targeting the GD2 solid tumor antigen in tumor immune microenvironment co-cultures and in vivo tumor immune …

Exploring The Transformative Effects Of Calorie Restriction On The Lacrimal Gland In Adult Mice, Olivier Mauduit, Prashant Kumar, Kaitlin K Scholand, Emre Aksan, Laura Schaefer, Anmar Abu-Romman, Vanessa Delcroix, Zhiyuan Yu, Aude I Sindikubwabo, Ron Korstanje, Helen P Makarenkova, Cintia S De Paiva

Faculty, Staff and Students Publications

Advanced age is one of the most recognizable risk factors for dry eye. Dry eye disease affects millions worldwide and can result from age-related lacrimal gland dysfunction, which correlates with a decline in lacrimal gland secretory cell function and chronic inflammation. This study investigated the potential of calorie restriction to maintain lacrimal gland and ocular surface health. Adult female C57BL/6 J mice were subjected to a 40% calorie restriction for 4 months, starting at 6-7 months and continuing until 10-11 months. These mice were compared to controls fed ad libitum. Bulk RNA sequencing of lacrimal glands, conjunctiva, and cornea subjected …

Liver-Specific Expression Of Hiv-1 Viral Protein R Causes Hepatic Steatosis And Glucose Intolerance In Male Mice, Neeti Agarwal, Pradip Saha, Claudia E Ramirez Bustamante, Sean M Hartig, Mark A Herman, Ashok Balasubramanyam, Jordan E Lake

Faculty, Staff and Students Publications

Background: Metabolic dysfunction-associated steatotic liver disease (MASLD) is increasingly recognized in people with HIV (PWH), with both HIV and antiretroviral therapy contributing to liver damage and glucose intolerance. However, the role of viral proteins derived from reservoirs in this process remains unclear.

Methods: Adeno-associated virus (AAV) constructs encoding a control protein or HIV-1 viral protein R (Vpr) driven by the thyroxine-binding globulin promoter were administered to male mice (n = 5 per group) fed regular chow or a high-fat diet (HFD). Young adult mice underwent intraperitoneal glucose tolerance testing and magnetic resonance imaging, followed by euthanasia. Liver and adipose tissues …

Hydrogen Sulfide Inhibits Recruitment Of Monocyte-Derived Tumor Associated Macrophages In Glioblastoma By Downregulating Cxcl12, Joseph Camarano, Morgan Roque, Gabrielle Gahn, Stephen Garrett Whipple, Danielle Terrell, Charles Ronkon, Jamie Toms, Anthony Sin, Bharat Guthikonda, Khatri Latha, Yuhui Yang, Xinggui Shen, Christopher G Kevil, Ganesh Rao, Sungho Lee

Faculty, Staff and Students Publications

Tumor associated macrophages (TAMs) directly contribute to the dismal prognosis of glioblastoma by preventing anti-tumor immunity and promoting tumor invasion and angiogenesis. Inhibiting TAM infiltration is a potential therapeutic strategy in glioblastoma, with several chemokine antagonists in early clinical development. Hydrogen sulfide, a gasotransmitter that regulates microglial accumulation in a wide range of CNS diseases, may be a novel therapeutic target to prevent TAM recruitment in glioblastoma. In this study, hydrogen sulfide concentrations were directly measured from 14 isocitrate dehydrogenase (IDH)-wildtype glioblastoma surgical samples and compared against overall survival as well as expression of TAM markers and chemokines. Effects of …

Carbonic Anhydrase Inhibition Sensitizes Group 3 Medulloblastoma To Radiotherapy, Cory M Richman, Alexandra Rasnitsyn, Borja L Holgado, Maria Vladoiu, Namal Abeysundara, Sandra Majo, Sara Chabi, Lucie J Taunay, Hiromichi Suzuki, Ichiyo Shibahara, Joonas Haapasalo, Jonelle G Pallotta, Tajana Douglas, Kaitlin Kharas, Kyle Juraschka, Oliver Ocsenas, Sachin A Kumar, Kristiina Nordfors, Ana Guerreiro Stücklin, Raul A Suarez, Jiao Zhang, Xiaochong Wu, Craig Daniels, Livia Garzia, Jüri Reimand, Olivier Saulnier, Thomas E Merchant, Celio Pouponnot, David R Raleigh, Michael D Taylor, Pasqualino De Antonellis

Faculty, Staff and Students Publications

Group 3 (G3) medulloblastoma constitutes the most aggressive molecular subgroup, and nearly all patients present with metastases upon recurrence. Treatment for newly diagnosed medulloblastoma relies on a combination of maximal safe surgical resection, followed by chemotherapy and ionizing radiation, and no therapies have been shown to confer a survival benefit at the time of recurrence. Given the limited therapeutic options available for patients with medulloblastoma, especially at recurrence, and the incomplete understanding of the molecular mechanisms underlying resistance to treatment, we sought to uncover actionable targets and biomarkers that could help refine patient selection and treatment of newly diagnosed medulloblastoma …

Aging Affects Lipid Homeostasis In Lacrimal Glands By Upregulating Lipogenesis And Changing Its Specificity, Seher Yuksel, Prashant Kumar, Sydney E Krenz, Kaitlin K Scholand, Zhiyuan Yu, Anastasiia Ivanova, Helen P Makarenkova, Sarah F Hamm-Alvarez, Igor A Butovich, Cintia S De Paiva

Faculty, Staff and Students Publications

Purpose: The lacrimal gland (LG) develops age-related alterations. This study investigated the lipid content of the accumulated secretions within the murine aged LG.

Methods: C57BL/6J animals of different ages (3 months, 12 months, and 20-26 months) were used. Published data of bulk RNA sequencing of aged LGs were used to investigate lipid pathways. Exorbital LGs were excised for histology or PCR. Histologic sections were stained with standard histochemical stains or immunostained using anti-adiponectin, anti-perilipin 2 antibodies, and BODIPY dye. LG lipidomes were investigated using unbiased, untargeted high-resolution liquid chromatography/mass spectrometry (LC/MS), and the data were processed using unbiased, untargeted principal …

Repeated Withdrawal Of A Glpr Agonist Induces Hyperleptinemia And Deteriorates Metabolic Health In Obese Aging Um-Het3 Mice, Nisi Jiang, Jiyuan Yin, Noah Lawrence, Jieyi Meng, Laurence T Maeyens, Ziying Xu, Xin Li, Mbolle Ekane, Ariana Chaudhary, Pengju Cao, Guannan Li, Carolina Solis-Herrera, Yi Zhu, Shangang Zhao

Children’s Nutrition Research Center Staff Publications

GLP-1-based therapy is highly effective in combating aging-associated metabolic diseases. However, the metabolic effects of frequent withdrawal from this therapy in aged, obese mice have not been previously studied. In this study, aged obese UM-HET3 mice were assigned to three groups: Group 1 received no liraglutide treatment (Lira OFF); Group 2 underwent 3 cycles of treatment followed by withdrawal (Lira ON/OFF); and Group 3 remained on continuous treatment (Lira ON). As expected, mice in Group 3 showed reduced body weight and food intake, along with improved metabolic health. In contrast, mice in Group 2 developed hyperleptinemia and visceral fat expansion, …

Lac-Phe Induces Hypophagia By Inhibiting Agrp Neurons In Mice, Hailan Liu, Veronica L Li, Qingzhuo Liu, Yao Liu, Cunjin Su, Hueyxian Wong, Na Yin, Hesong Liu, Xing Fang, Kristine M Mcdermott, Hueyzhong Wong, Meng Yu, Longlong Tu, Jonathan C Bean, Yongxiang Li, Mengjie Wang, Yue Deng, Yuhan Shi, Olivia Z Ginnard, Yuxue Yang, Junying Han, Megan E Burt, Sanika V Jossy, Chunmei Wang, Yongjie Yang, Benjamin R Arenkiel, Dong Kong, Yang He, Jonathan Z Long, Yong Xu

Faculty, Staff and Students Publications

Lactate-derived N-lactoyl-phenylalanine (Lac-Phe) was recently identified as an lactate-derived circulating metabolite that reduces feeding and obesity, but mechanisms that underlie the metabolic benefits of Lac-Phe remain unknown. Here we demonstrated that Lac-Phe directly inhibits hypothalamic neurons that express Agouti-related protein (AgRP), resulting in an indirect activation of anorexigenic neurons in the paraventricular nucleus of the hypothalamus (PVH). We also found that both AgRP inhibition and PVH activation are required to mediate Lac-Phe-induced hypophagia. Further, we show that Lac-Phe inhibits AgRP neurons via activating the ATP-sensitive potassium (KATP) channel, and inhibition of the KATP channel blunts effects of Lac-Phe to suppress …