Medical Molecular Biology Commons^™

Notch Signaling Regulates The Secretion Of Pro-Metastatic Factors In Extracellular Vesicles In Liposarcoma, Menchus Quan, Yi-Kai Liu, Ying Zhao, Madeline Kay, Kai Sun, Timothy P Gavin, Raphael E Pollock, W Andy Tao, Shihuan Kuang

The Brown Foundation: Institute of Molecular Medicine

Notch signaling is an emerging regulator of liposarcoma (LPS), but its role in mediating communication with the tumor microenvironment (TME) is unclear. Here, we investigate how Notch activation (NICD overexpression) alters the proteomes of LPS-derived extracellular vesicles (EVs). We used quantitative mass spectrometry to profile the EV proteome in multiple contexts: cultured LPS cells, LPS tumor, circulating EVs of LPS-bearing mice, and human LPS samples. We found that Notch signaling increases the secretion of EV proteins that favor tumor progression and metastasis but suppresses immune responses in murine LPS cells. Overlapping murine and human LPS data identifies 18 proteins that …

Glycosphingolipids Regulate Phosphatidylserine Transport Machinery That Operates At Er-Pm Contact Sites, Ritchel Gannaban, Sher Ali, Wei Chen, Melanie Nguyen, Li Lai, Travis I Moore, Yubin Zhou, John F Hancock, Junchen Liu

The Brown Foundation: Institute of Molecular Medicine

Plasma membrane (PM) localization of KRAS requires specific glycosphingolipids in the outer leaflet and phosphatidylserine (PS) in the inner leaflet. PM PS content is controlled by lipid transport proteins ORP5 and ORP8, which operate at ER-PM membrane contact sites (MCSs). Using high-resolution imaging, we now show that GSLs, including GM3 and SM4, are required to maintain ORP5 and ORP8 localization to MCSs. Genetic deletion or pharmacologic inhibition of enzymes required for the biosynthesis of GM3 or SM4 displaces PI4-kinase Type IIIα (PI4KIIIα) and its adaptor EFR3A from the PM, thereby reducing PM phosphatidylinositol 4-phosphate (PI4P) content. PM interactions of ORP5 …

Claudins Interact With Lilrb Immune Inhibitory Receptors To Promote Myeloid Immunosuppression In Cancer, Xiaoye Liu, Ryan Huang, Zhiqiang Ku, Jingjing Xie, Heyu Chen, Yubo He, Qi Lou, Chengcheng Zhang, Xing Yang, Cheryl Lewis, Jade Homsi, Ankit Gupta, Lei Dong, Kenian Chen, Annabel Tu, Liming Du, Hailong Yu, Qing Hu, Meng Fang, Bufan Li, A E M Adan Khan, Caroline Simith, Samuel John, Lin Xu, Ningyan Zhang, Zhiqiang An, Cheng Cheng Zhang

The Brown Foundation: Institute of Molecular Medicine

The mechanisms underlying tumor cell-myeloid cell interactions in the tumor microenvironment (TME) remain unclear, and predictive biomarkers for patient response to myeloid checkpoint blockade are lacking. This study identified specific binding between tight junction claudins (CLDNs) and leukocyte immunoglobulin-like receptor subfamily B2 (LILRB2) and LILRB5. In multiple human cancer cohorts, the spatial proximity of LILRB2-positive macrophages to CLDN-expressing cancer cells correlated with clinical outcomes, highlighting this spatial relationship as a potential biomarker. In syngeneic LILRB2-transgenic and humanized mouse models, CLDN18.2-LILRB2 interactions triggered bidirectional signaling, enhanced the immunosuppressive activity of myeloid cells, and accelerated tumor progression. These effects were reversed by …

Γδ T Cells At The Interface Of Innate And Adaptive Immunity In Cancer, Arnau Solé Casaramona, Martin F Bachmann, Eva Sevick-Muraca, Mona O Mohsen

The Brown Foundation: Institute of Molecular Medicine

γδ T cells are unconventional lymphocytes that bridge innate and adaptive immunity by combining recognition of stress-induced ligands independently of classical major histocompatibility complex molecules with the capacity to undergo clonal expansion and long-term adaptation. Their unusual ability to detect malignant transformation using semi-invariant T-cell receptors, butyrophilin recognition and natural killer-like receptors positions them as powerful effector cells in tumors that evade classical immune escape mechanisms. Furthermore, distinct γδ subsets have distinct phenotyping and specific tissue-residencies, which could be leveraged to modulate immunological responses. We evaluate engineered therapies and different experimental platforms for studying γδ T cell biology. We conclude …

Human Microglia In Brain Assembloids Display Region-Specific Diversity And Respond To Hyperexcitable Neurons Carrying Scn2a Mutation, Jiaxiang Wu, Xiaoling Chen, Jingliang Zhang, Kyle Wettschurack, Morgan Robinson, Weihao Li, Yuanrui Zhao, Ye-Eun Yoo, Brody A Deming, Yue Shu, Akila D Abeyaratna, Zhefu Que, Dongshu Du, Matthew Tegtmeyer, Chongli Yuan, William C Skarnes, Zhong-Yin Zhang, Jean-Christophe Rochet, Long-Jun Wu, Yang Yang

The Brown Foundation: Institute of Molecular Medicine

Microglia critically shape neuronal circuit development and function, yet their region-specific properties and roles in distinct circuits of the human brain remain poorly understood. In this study, we generated region-specific brain organoids (cortical, striatal, and midbrain), each integrated with human microglia, to fill this critical gap. Single-cell RNA sequencing uncovered six distinct microglial subtypes exhibiting unique regional signatures, including a subtype highly enriched for the GABAB receptor gene within striatal organoids. To investigate the contributions of microglia to neural circuitry, we created microglia-incorporated midbrain-striatal assembloids, modeling a core circuit node for many neuropsychiatric disorders, including autism. Using chemogenetics to activate …

Gh Alters Lymphatic Vessels In Female Mice And Stat5 Phosphorylation In Human Lymphatic Endothelial Cells, Christopher Walsh, Emily Scott, Elise Wagner, Jerome Walsh, Shashank Reddy, Arshad Ahmad, Reetobrata Basu, Eva Sevick-Muraca, Rich Brody, Uday Sandbhor, Sebastian Neggers, John J Kopchick

The Brown Foundation: Institute of Molecular Medicine

Disruption of lymphatic function underlies a broad spectrum of inflammatory and metabolic disorders, yet the hormonal pathways that regulate lymphatic biology remain poorly defined. GH, which is implicated in similar disease states, has an unclear role in lymphatic homeostasis. To address this gap, we investigated how chronic alterations in GH signaling alter lymphatic structure and function. Using transgenic mouse lines with increased, decreased, or absent GH action, we quantified the effect of GH on lymphatic pumping rate and lymphangiogenic remodeling during wound healing using near-infrared fluorescent imaging. We also measured markers of lymphatic endothelial cells using Western blot and immunohistochemistry …

Estrogen-Related Receptor Alpha Promotes Skeletal Muscle Regeneration And Mitigates Muscular Dystrophy, Thi Thu Hao Nguyen, Ya Xiang Huang, Svitlana Poliakova, Citu Citu, Eira Mann, Danesh H Sopariwala, Zhongming Zhao, Ashok Kumar, Vihang A Narkar

The Brown Foundation: Institute of Molecular Medicine

Skeletal muscle regeneration in chronic muscle diseases such as Duchenne Muscular Dystrophy (DMD) has remained clinically unsurmountable. Estrogen‐related receptor alpha (ERRα) plays a critical role in adult skeletal muscle metabolism and exercise fitness. Whether ERRα activation can drive muscle regeneration and mitigate dystrophy in DMD is not known. We have investigated ERRα signaling in pre‐clinical models of acute muscle injury and DMD. ERRα is induced in differentiating C2C12 myoblast and regenerating muscle. ERRα silencing suppressed proliferation and differentiation in C2C12 myoblasts. RNA sequencing revealed that angiogenic factor and proliferation genes were downregulated by ERRα knockdown in proliferating cells, whereas oxidative …

Somatostatin Receptor 2 Overexpression In Hepatocellular Carcinoma: Implications For Cancer Biology And Therapeutic Applications, Servando Hernandez Vargas, Solmaz Aghaamiri, Jack T Adams, Tyler M Bateman, Belkacem Acidi, Sukhen C Ghosh, Vahid Khalaj, Ahmed O Kaseb, Hop S Tran Cao, Majid Momeny, Ali Azhdarinia

The Brown Foundation: Institute of Molecular Medicine

Background: Somatostatin receptor 2 (SSTR2), a G protein-coupled receptor, is overexpressed in multiple malignancies, including hepatocellular carcinoma (HCC). While SSTR2 has traditionally been viewed as an inhibitory receptor involved in suppressing hormone secretion and cell proliferation, emerging evidence suggests a more complex role in cancer biology. However, the functional implications of SSTR2 expression in HCC remain poorly understood. This study aimed to systematically investigate the molecular landscape associated with SSTR2 expression in HCC and evaluate its potential as a therapeutic target.

Methods: SSTR2 expression patterns across 22 tumor types were assessed using TNMplot, and its expression in HCC was further …

Regional Heterogeneity Of The Blood-Brain Barrier, Marie Blanchette, Kaja Bajc, Benjamin D Gastfriend, Caterina P Profaci, Nadine Ruderisch, Cayce E Dorrier, Guo Zhong, Raquel Cuevas-Diaz Duran, Sean S Harvey, Iris H Garcia-Pak, Lucija Pintarić, Manon Leclerc, Louise Reveret, Vincent Émond, Annette Wang, Deepti Pant, Linus T Tsai, Frédéric Calon, Nina Isoherranen, Sean P Palecek, Eric V Shusta, Jiaqian Wu, Richard Daneman

The Brown Foundation: Institute of Molecular Medicine

The blood-brain barrier (BBB), formed by specialized endothelial cells (ECs), regulates the extracellular composition of the central nervous system (CNS). Little is known about whether there are regional specializations of the BBB that may control the function of specific neural circuits. We use single cell RNA-seq to characterize ECs from nine CNS regions in male mice: cortex, hippocampus, cerebellum, spinal cord, striatum, thalamus, hypothalamus, midbrain, and medulla/pons. Although there is a core BBB transcriptional profile, there are significant regional specializations. Stra6, a retinoid transporter, is highly enriched in the BBB of the nucleus accumbens shell (ShNAc) and ventral cochlear nucleus, …

Calcium-Sensing Receptor As A Novel Target For The Treatment Of Idiopathic Pulmonary Fibrosis, Richard T Bruce, Luis A J Mur, Jordanna Dally, Ryan Moseley, Rupert Ecker, Harry Karmouty-Quintana, Keir E Lewis, A John Simpson, Jeremy P T Ward, Christopher J Corrigan, Renata Z Jurkowska, Benjamin D Hope-Gill, Daniela Riccardi, Polina L Yarova

Faculty, Staff and Student Publications

Idiopathic pulmonary fibrosis (IPF) is a disease with a poor prognosis and no curative therapies. Fibroblast activation by transforming growth factor β1 (TGFβ1) and disrupted metabolic pathways, including the arginine-polyamine pathway, play crucial roles in IPF development. Polyamines are agonists of the calcium/cation-sensing receptor (CaSR), activation of which is detrimental for asthma and pulmonary hypertension, but its role in IPF is unknown. To address this question, we evaluated polyamine abundance using metabolomic analysis of IPF patient saliva. Furthermore, we examined CaSR functional expression in human lung fibroblasts (HLFs), assessed the anti-fibrotic effects of a CaSR antagonist, NPS2143, in TGFβ1-activated normal …

Single-Cell Rna Sequencing Identifies Molecular Biomarkers Predicting Late Progression To Cdk4/6 Inhibition In Patients With Hr+/Her2- Metastatic Breast Cancer, Linjie Luo, Peng Yang, Sofia Mastoraki, Xiayu Rao, Yan Wang, Akshara Singareeka Raghavendra, Senthil Damodaran, Kelly K Hunt, Jing Wang, Ziyi Li, Khandan Keyomarsi

Faculty, Staff and Student Publications

Background: Cyclin-dependent kinase 4/6 inhibitors (CDK4/6is) in combination with endocrine therapy are the standard treatment for patients with hormone receptor-positive, HER2-negative metastatic breast cancer (mBC). Despite the efficacy of CDK4/6is, intrinsic resistance occurs in approximately one-third of patients, highlighting the need for reliable predictive biomarkers.

Methods: Single-cell RNA sequencing analyzed metastatic tumors from HR+/HER2- mBC patients pre-CDK4/6i treatment at baseline (BL) and/or at disease progression. BL samples were from CDK4/6i responders (median progression-free survival [mPFS] = 25.5 months), while progressors were categorized as early-progressors (EP, mPFS = 3 months) and late-progressors (LP, mPFS = 11 months). Metastatic sites included liver, …

A Switch Protein Adapter For Anti-Lilrb4 Car-T Cells, Ryan Huang, Heyu Chen, Jingjing Xie, Qi Lou, Lingxiao Tan, Ningyan Zhang, Zhiqiang An, Samuel John, Cheng Cheng Zhang

The Brown Foundation: Institute of Molecular Medicine

Chimeric antigen receptor-T cell (CAR-T) immunotherapy has shown remarkable results for the treatment of certain hematologic malignancies. A redirection strategy that utilizes clinically relevant CAR-T cells in combination with adapter proteins may be an effective strategy to target other hematologic and solid cancers. We established a fusion antibody-based strategy with flexibility to target multiple tumor types in combination with a novel anti-leukocyte immunoglobulin-like receptor-B 4 (LILRB4) CAR-T cell. Specifically, we engineered switch protein (SwP) adapters containing the LILRB4 extracellular domain fused to either an anti-CD19 or anti-CD20 single-chain variable fragment (scFv). These SwPs were sufficient to stimulate anti-LILRB4 CAR-T cells …

Ligand Distances As Key Predictors Of Pathogenicity And Function In Nmda Receptors, Sukhan Kim, Ilona Krey, Piero Fariselli, Patrick May, Johannes R Lemke, Scott J Myers, Hongjie Yuan, Stephen F Traynelis, Dennis Lal

Faculty, Staff and Student Publications

Genetic variants in the genes GRIN1, GRIN2A, GRIN2B, and GRIN2D, which encode subunits of the N-methyl-D-aspartate receptor (NMDAR), have been associated with severe and heterogeneous neurologic and neurodevelopmental disorders, including early onset epilepsy, developmental and epileptic encephalopathy, intellectual disability, and autism spectrum disorders. Missense variants in these genes can result in gain or loss of the NMDAR function, requiring opposite therapeutic treatments. Computational methods that predict pathogenicity and molecular functional effects of missense variants are therefore crucial for therapeutic applications. We assembled 223 missense variants from patients, 631 control variants from the general population, and 160 missense variants characterized by …

Microglial Trem2 Promotes Phagocytic Clearance Of Damaged Neurons After Status Epilepticus, Dale B Bosco, Vaclav Kremen, Koichiro Haruwaka, Shunyi Zhao, Lingxiao Wang, Blake A Ebner, Jiaying Zheng, Manling Xie, Aastha Dheer, Jadyn F Perry, Abhijeet Barath, Aivi T Nguyen, Gregory A Worrell, Long-Jun Wu

The Brown Foundation: Institute of Molecular Medicine

In the central nervous system, triggering receptor expressed on myeloid cells 2 (TREM2) is exclusively expressed by microglia and is critical for microglial proliferation, migration, and phagocytosis. Microglial TREM2 plays an important role in neurodegenerative diseases, such as Alzheimer's disease and amyotrophic lateral sclerosis. However, little is known about how TREM2 affects microglial function within epileptogenesis. To investigate this, we utilized male TREM2 knockout (KO) mice within the intra-amygdala kainic acid seizure model. Electroencephalographic analysis, immunocytochemistry, and RNA sequencing revealed that TREM2 deficiency significantly promoted seizure-induced pathology. We found that TREM2 KO increased both the severity of acute status epilepticus …

Allosteric Competition And Inhibition In Ampa Receptors, W Dylan Hale, Alejandra Montaño Romero, Cuauhtemoc U Gonzalez, Vasanthi Jayaraman, Albert Y Lau, Edward C Twomey

Faculty, Staff and Student Publications

Excitatory neurotransmission is principally mediated by α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-subtype ionotropic glutamate receptors (AMPARs). Negative allosteric modulators are therapeutic candidates that inhibit AMPAR activation and can compete with positive modulators to control AMPAR function through unresolved mechanisms. Here we show that allosteric inhibition pushes AMPARs into a distinct state that prevents both activation and positive allosteric modulation. We used cryo-electron microscopy to capture AMPARs bound to glutamate, while a negative allosteric modulator, GYKI-52466, and positive allosteric modulator, cyclothiazide, compete for control of the AMPARs. GYKI-52466 binds in the ion channel collar and inhibits AMPARs by decoupling the ligand-binding domains from the …

G Protein Selectivity Profile Of Gpr56/Adgrg1 And Its Effect On Downstream Effectors, Raida Jallouli, Ana L Moreno-Salinas, Andréanne Laniel, Brian Holleran, Charlotte Avet, Trang Hoang, Kendra S Carmon, Michel Bouvier, Richard Leduc

Faculty, Staff and Student Publications

GPR56, an adhesion G-protein coupled receptor (aGPCRs) with constitutive and ligand-promoted activity, is involved in many physiological and pathological processes. Whether the receptor's constitutive or ligand-promoted activation occur through the same molecular mechanism, and whether different activation modes lead to functional selectivity between G proteins is unknown. Here we show that GPR56 constitutively activates both G12 and G13. Unlike constitutive activation and activation with 3-α-acetoxydihydrodeoxygedunin (3αDOG), stimulation with an antibody, 10C7, directed against GPR56's extracellular domain (ECD) led to an activation that favors G13 over G12. An autoproteolytically deficient mutant, GPR56-T383A, was also activated by 10C7 indicating that the tethered …

Antitumor Activity Of A Novel Lair1 Antagonist In Combination With Anti-Pd1 To Treat Collagen-Rich Solid Tumors, Bertha L Rodriguez, Jiawei Huang, Laura Gibson, Jared J Fradette, Hung-I H Chen, Czrina Cortez, Carmence Ho, Amir M Ashique, Vicky Y Lin, Suzanne Crawley, Julie M Roda, Peirong Chen, Bin Fan, Jeong Kim, James Sissons, Jonathan Sitrin, Daniel D Kaplan, Don L Gibbons, Lee B Rivera

Faculty, Staff and Student Publications

We recently reported that resistance to PD-1 blockade in a refractory lung cancer-derived model involved increased collagen deposition and the collagen-binding inhibitory receptor leukocyte-associated immunoglobulin-like receptor 1 (LAIR1). Thus, we hypothesized that LAIR1 and collagen cooperated to suppress therapeutic response. In this study, we report that LAIR1 is associated with tumor stroma and is highly expressed by intratumoral myeloid cells in both human tumors and mouse models of cancer. Stroma-associated myeloid cells exhibit a suppressive phenotype and correlate with LAIR1 expression in human cancer. NGM438, a novel humanized LAIR1 antagonist mAb, elicits myeloid inflammation and allogeneic T-cell responses by binding …

Lilrb4 On Multiple Myeloma Cells Promotes Bone Lesion By P-Shp2/Nf-Κb/Relt Signal Pathway, Hongying Wang, Lei Wang, Huiwen Luan, Jing Xiao, Zhiling Zhao, Pengfei Yu, Mi Deng, Yifan Liu, Shuhao Ji, Junjie Ma, Yan Zhou, Jiashen Zhang, Xianhui Meng, Juan Zhang, Xinyu Zhao, Chunling Li, Fangmin Li, Dapeng Wang, Shujuan Wei, Lijun Hui, Siman Nie, Changzhu Jin, Zhiqiang An, Ningyan Zhang, Yaopeng Wang, Cheng Cheng Zhang, Zunling Li

The Brown Foundation: Institute of Molecular Medicine

Background: Leukocyte Ig-like receptor B family 4 (LILRB4) as an immune checkpoint on myeloid cells is a potential target for tumor therapy. Extensive osteolytic bone lesion is the most characteristic feature of multiple myeloma. It is unclear whether ectopic LILRB4 on multiple myeloma regulates bone lesion.

Methods: The conditioned medium (CM) from LILRB4-WT and -KO cells was used to analyze the effects of LILRB4 on osteoclasts and osteoblasts. Xenograft, syngeneic and patient derived xenograft models were constructed, and micro-CT, H&E staining were used to observe the bone lesion. RNA-seq, cytokine array, qPCR, the activity of luciferase, Co-IP and western blotting …

Microglial P2y6 Calcium Signaling Promotes Phagocytosis And Shapes Neuroimmune Responses In Epileptogenesis, Anthony D Umpierre, Bohan Li, Katayoun Ayasoufi, Whitney L Simon, Shunyi Zhao, Manling Xie, Grace Thyen, Benjamin Hur, Jiaying Zheng, Yue Liang, Dale B Bosco, Mark A Maynes, Zhaofa Wu, Xinzhu Yu, Jaeyun Sung, Aaron J Johnson, Yulong Li, Long-Jun Wu

The Brown Foundation: Institute of Molecular Medicine

Microglial calcium signaling is rare in a baseline state but strongly engaged during early epilepsy development. The mechanism(s) governing microglial calcium signaling are not known. By developing an in vivo UDP fluorescent sensor, GRABUDP1.0, we discovered that UDP release is a conserved response to seizures and excitotoxicity across brain regions. UDP can signal through the microglial-enriched P2Y6 receptor to increase calcium activity during epileptogenesis. P2Y6 calcium activity is associated with lysosome biogenesis and enhanced production of NF-κB-related cytokines. In the hippocampus, knockout of the P2Y6 receptor prevents microglia from fully engulfing neurons. Attenuating microglial calcium signaling through Calcium Extruder (“CalEx”) …

Modulation Of The Blood-Brain Barrier By Sigma-1r Activation, Ellen M Unterwald

Faculty, Staff and Student Publications

Sigma non-opioid intracellular receptor 1 (Sigma-1R) is an intracellular chaperone protein residing on the endoplasmic reticulum at the mitochondrial-associated membrane (MAM) region. Sigma-1R is abundant in the brain and is involved in several physiological processes as well as in various disease states. The role of Sigma-1R at the blood-brain barrier (BBB) is incompletely characterized. In this study, the effect of Sigma-1R activation was investigated in vitro on rat brain microvascular endothelial cells (RBMVEC), an important component of the blood-brain barrier (BBB), and in vivo on BBB permeability in rats. The Sigma-1R agonist PRE-084 produced a dose-dependent increase in mitochondrial calcium, …

Antibody-Mediated Targeting Of Human Microglial Leukocyte Ig-Like Receptor B4 Attenuates Amyloid Pathology In A Mouse Model, Jinchao Hou, Yun Chen, Zhangying Cai, Gyu Seong Heo, Carla M Yuede, Zuoxu Wang, Kent Lin, Fareeha Saadi, Tihana Trsan, Aivi T Nguyen, Eleni Constantopoulos, Rachel A Larsen, Yiyang Zhu, Nicole D Wagner, Nolan Mclaughlin, Xinyi Cynthia Kuang, Alexander D Barrow, Dian Li, Yingyue Zhou, Shoutang Wang, Susan Gilfillan, Michael L Gross, Simone Brioschi, Yongjian Liu, David M Holtzman, Marco Colonna

The Brown Foundation: Institute of Molecular Medicine

Microglia help limit the progression of Alzheimer’s disease (AD) by constraining amyloid-β (Aβ) pathology, effected through a balance of activating and inhibitory intracellular signals delivered by distinct cell surface receptors. Human leukocyte Ig-like receptor B4 (LILRB4) is an inhibitory receptor of the immunoglobulin (Ig) superfamily that is expressed on myeloid cells and recognizes apolipoprotein E (ApoE) among other ligands. Here, we find that LILRB4 is highly expressed in microglia of patients with AD. Using mice that accumulate Aβ and carry a transgene encompassing a portion of the LILR region that includes LILRB4, we corroborated abundant LILRB4 expression in microglia …

Understanding The Function Of Pax5 In Development Of Docetaxel-Resistant Neuroendocrine-Like Prostate Cancers, Sreyashi Bhattacharya, Hannah Harris, Ridwan Islam, Sanika Bodas, Navatha S. Polavaram, Juhi Mishra, Dipanwita Das, Parthasarathy Seshacharyulu, Achyuth Kalluchi, Anirban Pal, Manish Kohli, Subodh M. Lele, Michael Muders, Surinder K. Batra, Paramita M. Ghosh, Kaustubh Datta, M. Jordan Rowley, Samikshan Dutta

Journal Articles: Biochemistry & Molecular Biology

Resistance to the current Androgen Receptor Signaling Inhibitor (ARSI) therapies has led to higher incidences of therapy-induced neuroendocrine-like prostate cancer (t-NEPC). This highly aggressive subtype with predominant small-cell-like characteristics is resistant to taxane chemotherapies and has a dismal overall survival. t-NEPCs are mostly treated with platinum-based drugs with a combination of etoposide or taxane and have less selectivity and high systemic toxicity, which often limit their clinical potential. During t-NEPC transformation, adenocarcinomas lose their luminal features and adopt neuro-basal characteristics. Whether the adaptive neuronal characteristics of t-NEPC are responsible for such taxane resistance remains unknown. Pathway analysis from patient gene-expression …

The Application Of Simultaneous Mainstem Bronchus Dilation With Pulmonary Artery Stenting In The Context Of Hypoplastic Left Heart Syndrome, Arun B Dutta, Daniel Gioeli

Faculty, Staff and Student Publications

The clinical success of combined androgen deprivation therapy (ADT) and radiotherapy (RT) in prostate cancer created interest in understanding the mechanistic links between androgen receptor (AR) signaling and the DNA damage response (DDR). Convergent data have led to a model where AR both regulates, and is regulated by, the DDR. Integral to this model is that the AR regulates the transcription of DDR genes both at a steady state and in response to ionizing radiation (IR). In this study, we sought to determine which immediate transcriptional changes are induced by IR in an AR-dependent manner. Using PRO-seq to quantify changes …

Entry Receptor Ldlrad3 Is Required For Venezuelan Equine Encephalitis Virus Peripheral Infection And Neurotropism Leading To Pathogenesis In Mice, Natasha M Kafai, Hana Janova, Matthew D Cain, Yael Alippe, Stefanie Muraro, Alan Sariol, Michelle Elam-Noll, Robyn S Klein, Michael S Diamond

The Brown Foundation: Institute of Molecular Medicine

Venezuelan equine encephalitis virus (VEEV) is an encephalitic alphavirus responsible for epidemics of neurological disease across the Americas. Low-density lipoprotein receptor class A domain-containing 3 (LDLRAD3) is a recently reported entry receptor for VEEV. Here, using wild-type and Ldlrad3-deficient mice, we define a critical role for LDLRAD3 in controlling steps in VEEV infection, pathogenesis, and neurotropism. Our analysis shows that LDLRAD3 is required for efficient VEEV infection and pathogenesis prior to and after central nervous system invasion. Ldlrad3-deficient mice survive intranasal and intracranial VEEV inoculation and show reduced infection of neurons in different brain regions. As LDLRAD3 is a determinant …

Loss Of Lgr5 Through Therapy-Induced Downregulation Or Gene Ablation Is Associated With Resistance And Enhanced Met-Stat3 Signaling In Colorectal Cancer Cells, Tressie A Posey, Joan Jacob, Ashlyn Parkhurst, Shraddha Subramanian, Liezl E Francisco, Kendra S Carmon

Faculty, Staff and Student Publications

Leucine-rich repeat-containing, G protein-coupled receptor 5 (LGR5) is highly expressed in colorectal cancer and cancer stem cells (CSCs) that play important roles in tumor initiation, progression, and metastasis. Loss of LGR5 has been shown to enhance therapy resistance. However, the molecular mechanisms that mediate this resistance remain elusive. In this study, we demonstrate conversion of LGR5+ colorectal cancer cells to an LGR5- state in response to chemotherapy, LGR5- targeted antibody-drug conjugates (ADCs), or LGR5 gene ablation led to activation of STAT3. Further investigation revealed increased STAT3 activation occurred as a result of increased mesenchymal epithelial transition (MET) factor receptor activity. …

Microrna-1 Attenuates The Growth And Metastasis Of Small Cell Lung Cancer Through Cxcr4/Foxm1/Rrm2 Axis, Parvez Khan, Jawed A. Siddiqui, Prakash Kshirsagar Dr., Ramakanth Chirravuri Venkata, Shailendra K. Maurya, Tamara Mirzapoiazova, Naveenkumar Perumal, Sanjib Chaudhary, Ranjana K. Kanchan, Mahek Fatima, Md Arafat Khan, Asad Ur Rehman, Imayavaramban Lakshmanan, Sidharth Mahapatra, Geoffrey A. Talmon, Prakash Kulkarni, Apar Kishor Ganti, Maneesh Jain, Ravi Salgia, Surinder K. Batra, Mohd W. Nasser

Journal Articles: Biochemistry & Molecular Biology

BACKGROUND: Small cell lung cancer (SCLC) is an aggressive lung cancer subtype that is associated with high recurrence and poor prognosis. Due to lack of potential drug targets, SCLC patients have few therapeutic options. MicroRNAs (miRNAs) provide an interesting repertoire of therapeutic molecules; however, the identification of miRNAs regulating SCLC growth and metastasis and their precise regulatory mechanisms are not well understood.

METHODS: To identify novel miRNAs regulating SCLC, we performed miRNA-sequencing from donor/patient serum samples and analyzed the bulk RNA-sequencing data from the tumors of SCLC patients. Further, we developed a nanotechnology-based, highly sensitive method to detect microRNA-1 (miR-1, …

Gpcrs And Fibroblast Heterogeneity In Fibroblast-Associated Diseases, Nidhi V. Dwivedi, Souvik Datta, Karim El-Kersh, Ruxana Sadikot Md, Mrcp, Apar Kishor Ganti, Surinder K. Batra, Maneesh Jain

Journal Articles: Biochemistry & Molecular Biology

G protein-coupled receptors (GPCRs) are the largest and most diverse class of signaling receptors. GPCRs regulate many functions in the human body and have earned the title of "most targeted receptors". About one-third of the commercially available drugs for various diseases target the GPCRs. Fibroblasts lay the architectural skeleton of the body, and play a key role in supporting the growth, maintenance, and repair of almost all tissues by responding to the cellular cues via diverse and intricate GPCR signaling pathways. This review discusses the dynamic architecture of the GPCRs and their intertwined signaling in pathological conditions such as idiopathic …

In Silico Identification Of A Β2-Adrenoceptor Allosteric Site That Selectively Augments Canonical Β2ar-Gs Signaling And Function, Sushrut D Shah, Christoffer Lind, Francesco De Pascali, Raymond B Penn, Alexander D Mackerell, Deepak A Deshpande

Department of Biochemistry and Molecular Biology Faculty Papers

Activation of β2-adrenoceptors (β2ARs) causes airway smooth muscle (ASM) relaxation and bronchodilation, and β2AR agonists (β-agonists) are front-line treatments for asthma and other obstructive lung diseases. However, the therapeutic efficacy of β-agonists is limited by agonist-induced β2AR desensitization and noncanonical β2AR signaling involving β-arrestin that is shown to promote asthma pathophysiology. Accordingly, we undertook the identification of an allosteric site on β2AR that could modulate the activity of β-agonists to overcome these limitations. We employed the site identification by ligand competitive saturation (SILCS) computational method to comprehensively map the entire 3D structure of in silico-generated β2AR intermediate conformations and identified …

D121 Located Within The Dry Motif Of P2y12 Is Essential For P2y12-Mediated Platelet Function., Carol Dangelmaier, Benjamin Mauri, Akruti Patel, Satya P Kunapuli, John C Kostyak

Department of Medicine Faculty Papers

Platelets are anucleate cells that mediate hemostasis. This occurs via a primary signal that is reinforced by secreted products such as ADP that bind purinergic receptors (P2Y1 and P2Y12) on the platelet surface. We recently identified a human subject, whom we termed platelet defect subject 25 (PDS25) with a platelet functional disorder associated with the P2Y12 receptor. PDS25 has normal blood cell counts and no history of bleeding diathesis. However, platelets from PDS25 have virtually no response to 2-MeSADP (a stable analogue of ADP). Genetic analysis of P2Y12 from PDS25 revealed a heterozygous mutation of D121N within the DRY motif. …

Tigit Is The Central Player In T-Cell Suppression Associated With Car T-Cell Relapse In Mantle Cell Lymphoma, Vivian Changying Jiang, Dapeng Hao, Preetesh Jain, Yijing Li, Qingsong Cai, Lei Nie, Jingling Jin, Wei Wang, Heng-Huan Lee, Yuxuan Che, Enyu Dai, Guangchun Han, Ruiping Wang, Kunal Rai, Andrew Futreal, Christopher Flowers, Linghua Wang, Michael Wang

Faculty, Staff and Student Publications

BACKGROUND: Chimeric antigen receptor (CAR) T-cell therapy using brexucabtagene autoleucel (BA) induces remission in many patients with mantle cell lymphoma (MCL), and BA is the only CAR T-cell therapy approved by the FDA for MCL. However, development of relapses to BA is recognized with poor patient outcomes. Multiple CAR T-cell therapies have been approved for other lymphomas and the resistance mechanisms have been investigated. However, the mechanisms underlying BA relapse in MCL have not been investigated and whether any previously reported resistance mechanisms apply to BA-relapsed patients with MCL is unknown.

METHODS: To interrogate BA resistance mechanisms in MCL, we …