Medical Sciences Commons^™

Galntl5 Binds Galnac And Is Required For Migration Through The Uterotubal Junction And Sperm-Zona Pellucida Binding, Taichi Noda, Reika Uriu, Daisuke Mashiko, Hina Shinohara, Yongcun Qu, Ayumu Taira, Ryan M Matzuk, Duri Tahala, Motochika Nakano, Kimi Araki, Zhifeng Yu, Ying Zhang, Martin M Matzuk, Masahito Ikawa

Faculty, Staff and Students Publications

Objective: To review the global impact of the COVID-19 pandemic on stroke care-metrics and report data from a health system in Houston.

Methods: We performed a meta-analysis of the published literature reporting stroke admissions, intracerebral hemorrhage (ICH) cases, number of thrombolysis (tPA) and thrombectomy (MT) cases, and time metrics (door to needle, DTN; and door to groin time, DTG) during the pandemic compared to prepandemic period. Within our hospital system, between January-June 2019 and January-June 2020, we compared the proportion of stroke admissions and door to tPA and MT times.

Results: A total of 32,640 stroke admissions from 29 studies …

Bard1: A Friend Or Foe In Pancreatic Ductal Adenocarcinoma?, Lily Zekavat, Aditi Jain

Department of Surgery Faculty Papers

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive solid malignancy with poor overall prognosis and limited response to standard treatments. Growing interest in the modulation of DNA repair mechanisms, including the homologous recombination (HR) repair pathway, has opened new avenues for therapeutic development. BARD1 (BRCA1-Associated RING Domain 1) plays a complex role in tumor biology, functioning either as a tumor suppressor or as an oncogenic driver, depending on isoform expression, cellular context, and regulatory environment. In this review, we examine the dual roles of BARD1, focusing on its regulation and paradoxical activities in PDAC. We summarize evidence that BARD1 and BARD1 …

Sorting Nexin 3 Promotes Ischemic Retinopathy Through Rip1- And Rip3-Mediated Myeloid Cell Necroptosis And Mitochondrial Fission, Jiaojiao Wang, Chunhong Zhou, Kai Zhuang, Jiami Zou, Wanlu Qiu, Mei Jin, Weile Ye, Pinglian Yang, Zhihua Zheng, Qing Zhou, Zunnan Huang, Yuanxiang Wang, Peiqing Liu, Jing Lu, Yuqing Huo, Zhiping Liu

Faculty, Staff and Students Publications

Proliferative retinopathy is a leading cause of irreversible blindness in humans; however, the molecular mechanisms behind the immune cell–mediated retinal angiogenesis remain poorly elucidated. Here, using single-cell RNA sequencing in an oxygen-induced retinopathy (OIR) model, we identified an enrichment of sorting nexin (SNX)-related pathways, with SNX3, a member of the SNX family that is involved in endosomal sorting and trafficking, being significantly upregulated in the myeloid cell subpopulations of OIR retinas. Immunostaining showed that SNX3 expression is markedly increased in the retinal microglia/macrophages of mice with OIR, which is mainly located within and around the neovascular tufts. Myeloid cell-specific deficiency …

Elevated Nr2f1 Underlies The Persistence Of Invasive Disease After Treatment Of Braf-Mutant Melanoma, Manoela Tiago, Timothy J Purwin, Casey D Stefanski, Renaira Oliveira Da Silva, Mitchell E Fane, Yash Chhabra, Jelan I Haj, Jessica Lf Teh, Rama Kadamb, Weijia Cai, Sheera R Rosenbaum, Vivian Chua, Nir Hacohen, Michael A Davies, Jessie Villanueva, Inna Chervoneva, Ashani T Weeraratna, Dan A Erkes, Claudia Capparelli, Julio A Aguirre-Ghiso, Andrew E Aplin

Faculty, Staff and Student Publications

Despite the success of targeted inhibitors in cutaneous melanoma, therapeutic responses are limited by the aged tumor microenvironment and drug-tolerant residual cells. Given the similarities between drug tolerance and cellular dormancy, we studied the dormancy marker, nuclear receptor subfamily 2 group F member 1 (NR2F1), in response to BRAF-V600E inhibitors (BRAFi) plus MEK inhibitors (MEKi) in BRAF-mutant melanoma models. Transcriptomic analysis of melanoma patient samples treated with BRAFi + MEKi showed increased NR2F1. NR2F1 was highly expressed in the drug-tolerant invasive cell state of minimal residual disease in patient-derived and mouse-derived xenografts on BRAFi + MEKi. NR2F1 over-expression was sufficient …

Setd2 Suppresses Tumorigenesis In A Krasg12c-Driven Lung Cancer Model, And Its Catalytic Activity Is Regulated By Histone Acetylation, Ricardo J Mack, Natasha M Flores, Geoffrey C Fox, Hanyang Dong, Metehan Cebeci, Simone Hausmann, Tourkian Chasan, Jill M Dowen, Brian D Strahl, Pawel K Mazur, Or Gozani

Faculty, Staff and Student Publications

Histone H3 trimethylation at lysine 36 (H3K36me3) is a key chromatin modification that regulates fundamental physiological and pathological processes. In humans, SETD2 is the only known enzyme that catalyzes H3K36me3 in somatic cells and is implicated in tumor suppression across multiple cancer types. While there is considerable crosstalk between the SETD2-H3K36me3 axis and other epigenetic modifications, much remains to be understood. Here, we show that Setd2 functions as a potent tumor suppressor in a KRASG12C-driven lung adenocarcinoma (LUAD) mouse model, and that acetylation enhances SETD2 in vitro methylation of H3K36 on nucleosome substrates. In vivo, Setd2 ablation accelerates lethality in …

Developmental Transformations Of Purkinje Cells Tracked By Dna Electrokinetic Mobility, Cheryl Brandenburg, Garrett W Crutcher, Andrea J Romanowski, Sarah G Donofrio, Lita R Duraine, Richard N A Owusu-Mensah, Benjamin H Cooper, Izumi Sugihara, Gene J Blatt, Roy V Sillitoe, Alexandros Poulopoulos

Duncan NRI Faculty and Staff Publications

Brain development begins with neurogenesis in progenitor zones and ends with expansive, intricately-patterned cellular diversity in the adult brain. We took advantage of bioelectric interactions between DNA and embryonic tissue to perform "stereo-tracking," a developmental targeting strategy that differentially labels cells at different depths within progenitor zones. This 3D labeling was achieved by delivery of plasmids with distinct electrokinetic mobilities in utero. We applied stereo-tracking with light sheet imaging in the cerebellum and identified that Purkinje cells follow embryonically committed developmental trajectories, linking distinct progenitor zone subfields to the mature topography of the cerebellar cortex. We additionally identified an unexpected …

Loss Of Ptdss1 In Tumor Cells Improves Immunogenicity And Response To Anti-Pd-1 Therapy, Jielin Liu, Shelley Herbrich, Sreyashi Basu, Yulong Chen, Ashwat Nagarajan, Swetha Anandhan, Sangeeta Goswami, Liangwen Xiong, Baoxiang Guan, Padmanee Sharma

Faculty, Staff and Student Publications

PTDSS1 (phosphatidylserine synthase 1) encodes an enzyme that facilitates production of phosphatidylserine (PS), which mediates a global immunosuppressive signal. Here, based on in vivo CRISPR screen, we identified PTDSS1 as a target to improve anti-PD-1 therapy. Depletion of Ptdss1 in tumor cells increased expression of interferon-γ (IFN-γ)-regulated genes, including B2m, Cxcl9, Cxcl10, and Stat1, even in the absence of IFN-γ stimulation in vitro. Loss of Ptdss1 in tumor cells also led to increased expression of MHC-I, enhanced cytotoxicity of CD8+ T cells, and increased frequency of an iNOS+ myeloid subset. A gene signature derived from the …

Infusion Of Blood From Young And Old Mice Modulates Amyloid Pathology, Matias Pizarro, Ruben Gomez-Gutierrez, Ariel Caviedes, Catalina Valdes, Ute Woehlbier, Cristian Vargas, Mauricio Hernandez, Claudia Duran-Aniotz, Rodrigo Morales

Faculty, Staff and Student Publications

Alzheimer's disease (AD) is a neurodegenerative disease characterized by the accumulation of misfolded proteins in the brain. Recently, the impact of blood components in the progression of this disease has come to attention. This study investigates the effects of infusing blood from young and old wild-type mice into transgenic mice that model AD brain amyloidosis. Impaired memory and Aβ accumulation were observed in mice infused with blood from old donors. A proteomic analysis in the brain of these mice identified alterations in components related to synaptogenesis and the endocannabinoid system. The α2δ2 protein, associated with neuronal calcium regulation, was validated …

The Colonic Crypt: Cellular Dynamics And Signaling Pathways In Homeostasis And Cancer, Anh L. Nguyen, Molly A. Lausten, Bruce M. Boman

College of Life Sciences Faculty Papers

The goal of this review is to expand our understanding of how the cellular organization of the normal colonic crypt is maintained and elucidate how this intricate architecture is disrupted during tumorigenesis. Additionally, it will focus on implications for new therapeutic strategies targeting Epithelial-Mesenchymal Transition (EMT). The colonic crypt is a highly structured epithelial unit that functions in maintaining homeostasis through a complex physiological function of diverse cell types: SCs, transit-amplifying (TA) progenitors, goblet cells, absorptive colonocytes, Paneth-like cells, M cells, tuft cells, and enteroendocrine cells. These cellular subpopulations are spatially organized and regulated by multiple crucial signaling pathways, including …

Human Toxocariasis, Susana Lopez-Alamillo, Pravallika Padyala, Megan Carey, Megan M Duffey, Jill E Weatherhead

Faculty, Staff and Students Publications

Human toxocariasis is a globally prevalent zoonotic parasitic infection caused by larvae of Toxocara species, primarily Toxocara canis and Toxocara cati. Toxocariasis is commonly transmitted to humans through the ingestion of embryonated Toxocara eggs found in contaminated soil, water, or on surfaces contaminated with animal feces. Unlike in dogs and cats, humans are not definitive hosts for Toxocara spp., and, as a result, Toxocara larvae do not complete their life cycle in humans. Instead, following accidental oral ingestion of embryonated eggs, Toxocara larvae undergo an aberrant larval migratory cycle to various organs including the lungs, liver, muscles, and central …

Neurotransmitter Signaling In Molecular And Behavioral Immune Responses To Pathogens In C Elegans, Benson Otarigho, Alejandro Aballay

Faculty, Staff and Student Publications

Neurotransmitter signaling pathways play major roles in both molecular and behavioral defenses against pathogen invasion, shaping the ability of Caenorhabditis elegans to sense and respond to environmental challenges. Given the conservation of neurotransmitter signaling pathways, their understanding may not only provide insights into the neurobiology of C. elegans but also has broader implications for our understanding of neural-immune interactions and host defense mechanisms in higher organisms. In this review, we discussed the literature on various neurotransmitter signaling pathways, including serotonergic, dopaminergic/octopaminergic, GABAergic, and glutamatergic pathways, and how these pathways modulate molecular and behavioral immune defense against pathogens.

Retinoid-X-Receptor As A Mediator Of Poststroke Recovery By Reversing Age-Associated Phenotypes Of Microglia/Hematogenous Macrophages, Shun-Ming Ting, Xiurong Zhao, Guanghua Sun, Mercedes Ricote, Jaroslaw Aronowski

Faculty, Staff and Student Publications

After stroke, microglia and hematogenous macrophages, together referred to as MΦ, clear dead cells and cellular debris in the infarcted brain through phagocytosis as an essential part of the recovery process. However, the phagocytic capability of MΦ declines with age. Furthermore, aged MΦ become overactivated in response to stroke, enhancing secondary brain injury. In this study, we demonstrated that by reversing the age-related dysfunctions in MΦ through activating the retinoid X receptor (RXR), the recovery after stroke in the aged brain could be improved. Using RNA-sequencing, we compared the transcriptomes between MΦ isolated from the brains of young and aged …

Inhibition Of The Ufd-1-Npl-4 Complex Triggers An Aberrant Immune Response In Caenorhabditis Elegans, Rajneesh Rao, Alejandro Aballay, Jogender Singh

Faculty, Staff and Student Publications

The UFD-1 (ubiquitin fusion degradation 1)-NPL-4 (nuclear protein localization homolog 4) heterodimer is involved in extracting ubiquitinated proteins from several plasma membrane locations, including the endoplasmic reticulum. This heterodimer complex helps in the degradation of ubiquitinated proteins via the proteasome with the help of the AAA+ATPase CDC-48. While the ubiquitin-proteasome system is known to have important roles in maintaining innate immune responses, the role of the UFD-1-NPL-4 complex in regulating immunity remains elusive. In this study, we investigate the role of the UFD-1-NPL-4 complex in maintaining

Infectious Prions In Brains And Muscles Of Domestic Pigs Experimentally Challenged With The Bse, Scrapie, And Cwd Agents, Francisca Bravo-Risi, Fraser Brydon, Angela Chong, Kane Spicker, Justin J Greenlee, Glenn Telling, Claudio Soto, Sandra Pritzkow, Marcelo A Barria, Rodrigo Morales

Faculty, Staff and Student Publications

Experimental studies suggest that animal species not previously described as naturally infected by prions are susceptible to prion diseases affecting sheep, cattle, and deer. These interspecies transmissions may generate prions with unknown host ranges. Pigs are susceptible to prions from different origins, including deer chronic wasting disease (CWD), sheep scrapie, and bovine spongiform encephalopathy (BSE). Here, we studied prions in brains and muscles from pigs previously infected with these different prion sources. Specifically, we measured the total prion protein (PrP) and PK-resistant PrP by western blot. Seeding activity in these tissues was evaluated using the protein misfolding cyclic amplification (PMCA) …

Dissecting The Effect Of Mitochondrial Bcat Inhibition In Methylmalonic Acidemia, Madeline G Hemmingsen, Guo-Fang Zhang, Yunhan Ma, Hannah Marchuk, Kalyani R Patel, Tong Chen, Xinning Li, Mark Chapman, Sabrina Collias, Dolores H Lopez-Terrada, James Beasley, Ashlee R Stiles, Randy J Chandler, Charles P Venditti, Sarah P Young, Mercedes Barzi, Beatrice Bissig-Choisat, Doug Krafte, Christopher B Newgard, Karl-Dimiter Bissig

Faculty, Staff and Students Publications

Methylmalonic acidemia (MMA) is a severe metabolic disorder affecting multiple organs because of a distal block in branched-chain amino acid (BCAA) catabolism. Standard of care is limited to protein restriction and supportive care during metabolic decompensation. Severe cases require liver/kidney transplantation, and there is a clear need for better therapy. Here, we investigated the effects of a small molecule branched-chain amino acid transaminase (BCAT) inhibitor in human MMA hepatocytes and an MMA mouse model. Mitochondrial BCAT is the first step in BCAA catabolism, and reduction of flux through an early enzymatic step is successfully used in other amino acid metabolic …

Testis Expressed 50 Is Essential For Maintaining Sperm Acrosome Integrity During Epididymal Transit, Saori Haga, Kaori Nozawa, Ferheen Abbasi, Katarzyna Kent, Naoko Nagasawa, Tsutomu Endo, Haruhiko Miyata, Masahito Ikawa, Martin M Matzuk, Yoshitaka Fujihara

Faculty, Staff and Students Publications

In mammals, sperm formation is completed in the seminiferous tubules within the testis, and sperm maturation occurs during the epididymal transit of the spermatozoa. Sperm morphology drastically changes when abnormal spermatozoa migrate from the testis to the epididymis. Detailed molecular mechanisms for sperm survival in the epididymis have not been determined yet. Globozoospermia is a cause of male infertility and is characterized by round-headed spermatozoa without acrosomes, an abnormal sperm nuclear membrane, and sperm midpiece defects. Testis expressed 50 (Tex50) is a testis-enriched gene that is expressed in mice and humans. Using CRISPR-Cas9, we generated Tex50 knockout (KO) …

Computationally Resolved Neuroprogenitor Cell Biomarkers Associate With Human Disorders, Gerarda Cappuccio, William T Choi, Fatih Semerci, Jill A Rosenfeld, Toni Claire Tacorda, Guantong Qi, Anthony W Zoghbi, Yi Zhong, Hu Chen, Pengfei Liu, Zhandong Liu, Mirjana Maletić-Savatić

Duncan NRI Faculty and Staff Publications

Adult hippocampal neurogenesis, the process of generating new neurons, relies on a rare population of neural stem and progenitor cells (NPCs) within the dentate gyrus complex microenvironment. Discovering the specific genes that define these cells is vital yet challenging due to overlapping expression patterns, limiting detection of rare cell populations using traditional approaches. By employing the computational digital sorting algorithm (DSA) that deconvolves complex gene expression data based on pattern recognition, we identified 129 genes enriched in murine NPCs. We validated these genes against published single-cell RNA sequencing (scRNA-seq) data and discovered that 25 human orthologs were known to cause …

Identification Of Cobra And Viper Bites In Southern India Using Enzyme-Linked Immunosorbent Assay, Tejeswara Rao Asuru, Raskin Erusan Rajagopal, Albert Rajendran, Gulistan Parveen, Anushka Das, Pabitha Devi, Swapan K Dasgupta, Shantaraman Kalyanaraman, Prasenjit Guchhait, Perumal Thiagarajan

Faculty, Staff and Students Publications

Introduction: Snakebite-related deaths are major concerns in populations worldwide that lack access to medical care. Current treatment of snakebites includes administration of polyspecific and polyvalent heterologous equine antiserum. Swift diagnosis of the species of snake responsible is essential to initiate a specific treatment.

Methods: We generated murine monoclonal and rabbit polyclonal antibodies against the venom of the 3 most common venomous snakes in southern India: the Russell viper, the saw-scaled viper, and the Indian cobra. We developed an enzyme-linked immunosorbent assay to distinguish the snake by analyzing the exudates from the snakebite wound.

Results: Monoclonal antibody EC3 reacts specifically with …

Gene Context Drift Identifies Drug Targets To Mitigate Cancer Treatment Resistance, Amir Jassim, Birgit V Nimmervoll, Sabrina Terranova, Erica Nathan, Linda Hu, Jessica T Taylor, Katherine E Masih, Lisa Ruff, Matilde Duarte, Elizabeth Cooper, Gunjan Katyal, Melika Akhbari, Reuben J Gilbertson, Jennifer C Coleman, Joseph S Toker, Colton Terhune, Gabriel Balmus, Stephen P Jackson, Hailong Liu, Tao Jiang, Michael D Taylor, Kui Hua, Jean E Abraham, Mariella G Filbin, Anthony Hill, Anarita Patrizi, Neil Dani, Aviv Regev, Maria K Lehtinen, Richard J Gilbertson

Faculty, Staff and Students Publications

Cancer treatment often fails because combinations of different therapies evoke complex resistance mechanisms that are hard to predict. We introduce REsistance through COntext DRift (RECODR): a computational pipeline that combines co-expression graph networks of single-cell RNA sequencing profiles with a graph-embedding approach to measure changes in gene co-expression context during cancer treatment. RECODR is based on the idea that gene co-expression context, rather than expression level alone, reveals important information about treatment resistance. Analysis of tumors treated in preclinical and clinical trials using RECODR unmasked resistance mechanisms -invisible to existing computational approaches- enabling the design of highly effective combination treatments …

Lewy Body Dementia Promotion By Air Pollutants, Xiaodi Zhang, Haiqing Liu, Xiao Wu, Longgang Jia, Kundlik Gadhave, Lena Wang, Kevin Zhang, Hanyu Li, Rong Chen, Ramhari Kumbhar, Ning Wang, Chantelle E Terrillion, Bong Gu Kang, Bin Bai, Minhan Park, Ma Cristine Faye Denna, Shu Zhang, Wenqiang Zheng, Denghui Ye, Xiaoli Rong, Liu Yang, Lili Niu, Han Seok Ko, Weiyi Peng, Lingtao Jin, Mingyao Ying, Liana S Rosenthal, David W Nauen, Alex Pantelyat, Mahima Kaur, Kezia Irene, Liuhua Shi, Rahel Feleke, Sonia García-Ruiz, Mina Ryten, Valina L Dawson, Francesca Dominici, Rodney J Weber, Xuan Zhang, Pengfei Liu, Ted M Dawson, Shizhong Han, Xiaobo Mao

Faculty, Staff and Student Publications

Evidence links air pollution to dementia, yet its role in Lewy body dementia (LBD) remains unclear. Here we showed in a cohort of 56.5 million individuals across the U.S. that PM2.5 exposure raises LBD risk. Mechanistically, we found PM2.5 exposure led to brain atrophy in wild-type mice, an effect not seen in α-synuclein (αSyn)-deficient mice. PM2.5 exposure generated a highly pathogenic αSyn strain, PM-PFF, with enhanced proteinase K-resistance and neurotoxicity, resembling αSyn LBD strains. PM2.5 samples from China, the U.S., and Europe consistently induced proteinase-resistant αSyn strains and in vivo pathology. Transcriptomic analyses revealed shared responses between PM2.5-exposed mice and …

Human Papillomavirus Integration Induces Oncogenic Host Gene Fusions In Oropharyngeal Cancers, Nusrat Khan, Keiko Akagi, Shiming Jiang, Joe Dan Dunn, Bo Jiang, Weihong Xiao, Madison P O'Hara, Li Shen, Qi Wang, Vakul Mohanty, Jing Wang, Sara Goodwin, Jamie L Hutchins, Kevin R Coombes, Jagannadha K Sastry, David E Symer, Maura L Gillison

Faculty, Staff and Student Publications

HPV integration disrupts host genomic structure and expression, but whether these alterations promote cancer development remains unclear. Multiple genomic analyses of oropharyngeal cancers identified several host fusion genes, including recurrent FGFR3-TACC3 fusions, expressed from rearranged genomic loci adjacent to HPV integration sites. Evolutionary modeling implicated integration of virus concatemers into the host genome as a common initiating event in fusion formation. Co-expression of HPV16 E6/E7 and FGFR3-TACC3, but neither alone, was sufficient for tumor development in both xenograft and syngeneic mouse models and led to unique transcriptional programs implicated in carcinogenesis. FGFR3-TACC3 expression decreased the ubiquitination and degradation of …

Persistent Na+ Current Couples Spreading Depolarization To Seizures In Scn8a Gain-Of-Function Mice, Isamu Aiba, Yao Ning, Jeffrey L Noebels

Faculty, Staff and Students Publications

Spreading depolarization (SD) is a slowly propagating wave of massive cellular depolarization that transiently impairs the function of affected brain regions. Although SD typically arises as an isolated hemispheric event, we previously reported that reducing M-type potassium current (IKM) by ablation of Kcnq2 in forebrain excitatory neurons results in tightly coupled spontaneous bilateral seizure–SD complexes in the awake mouse cortex.

Here we find that enhanced persistent Na+ current attributable to gain-of-function mutations in Scn8a (N1768D/+, hereafter D/+) produces a similar compound cortical excitability phenotype. Chronic direct-current (DC)-band EEG recording detected spontaneous bilateral seizure–SD complexes accompanied by seizures with …

An Allele-Agnostic Mutant-Kras Inhibitor Suppresses Tumor Maintenance Signals And Reprograms Tumor Immunity In Pancreatic Cancer, Kathleen M Mcandrews, Francesca Paradiso, Clint A Stalnecker, Benson S Chellakkan, Fredrik I Thege, David H Peng, Barbara A Moreno Diaz, Hikaru Sugimoto, Sarah I Patel, Krishnan K Mahadevan, Michelle L Kirtley, Danielle Wills, Amari M Sockwell, Andre Luis F Fonseca, Yunhe Liu, Kimal I Rajapakshe, Nathaniel G Yee, Phuong Thao Tran, Huda Alchikh Omar, Antonio Tedeschi, Fiorella Schischlik-Siegl, Andrew S Boghossian, Matthew G Rees, Melissa M Ronan, Jennifer A Roth, Dorothea Rudolph, Martin Aichinger, Florian Ebner, Artem V Artemov, Jesse Lipp, Laura Pisarsky, Valerie Laura Herrmann, John Park, Jörg F Rippmann, Otmar Schaaf, Vanessa Chandler, Mariah Williams, Charles E Deckard, Linghua Wang, Channing J Der, Christopher Vellano, Paola A Guerrero, Timothy P Heffernan, Raghu Kalluri, Anirban Maitra

Faculty, Staff and Student Publications

KRAS is among the most frequently mutated oncogenes in cancer, and for decades, efforts at pharmacological blockade of its function in solid cancers have been unsuccessful. A notable advance in this endeavor is the recent development of small molecule KRAS inhibitors, which enable direct targeting of the mutant oncoprotein. Here, we comprehensively evaluate the pre-clinical efficacy of BI-2493 a panKRASi, a first-in-class allele agnostic mutant KRAS inhibitor, in pancreatic ductal adenocarcinoma (PDAC). We report effective tumor growth suppression across a broad range of models, including cell lines, patient-derived xenografts (PDXs), syngeneic orthotopic models, and prolonged survival in genetically engineered mouse …

Chp1 Promotes Lipid Droplet Growth And Regulates The Localization Of Key Enzymes For Triacylglycerol Synthesis, Guang Yang, Ximing Du, Dougall Norris, Armella Zadoorian, Yuyuan Zheng, Mingming Gao, Andrew J Brown, Shane T Grey, Chun Zhou, Hongyuan Yang

Faculty, Staff and Student Publications

The glycerol-3-phosphate (G-3-P) pathway is central to the synthesis of triacylglycerols (TAGs) and glycerophospholipids, essential for membrane biogenesis and lipid storage. The first and rate-limiting step in this pathway is catalyzed by glycerol-3-phosphate acyltransferases (GPATs), with microsomal GPAT3 and GPAT4 being evolutionarily conserved and predominant in most tissues. While previous studies have implicated Calcineurin B homologous protein 1 (CHP1) as a cofactor for GPAT4, the broader role of CHP1 in regulating microsomal GPATs and TAG biosynthesis remains unclear. Here, we demonstrate that CHP1 is a critical regulator of both GPAT3 and GPAT4, essential for their stability, enzymatic activity, and lipid …

Efficacy Of Atr Kinase Inhibitor Elimusertib Monotherapy Or Combination In Tumors With Dna Damage Response Pathway And Other Genomic Alterations, Kaushik Varadarajan, Christian X Cruz Pico, Kurt W Evans, Maria Gabriela Raso, Yasmeen Qamar Rizvi, Xiaofeng Zheng, Dhruv Chachad, Timothy P Diperi, Bailiang Wang, Stephen M Scott, Ming Zhao, Argun Akcakanat, Antje M Wengner, Timothy A Yap, Funda Meric-Bernstam

Faculty, Staff and Student Publications

The ataxia telangiectasia and RAD3-related (ATR) kinase functions with ataxia telangiectasia-mutated (ATM) kinase as a modulator of DNA damage response (DDR). We assessed the antitumor effects of the ATR inhibitor elimusertib (BAY-1895344) in patient-derived xenograft (PDX) models with DDR alterations. Antitumor activity was assessed by change in tumor volume (TV) from baseline. Responses were categorized as follows: partial response (PR), ≥30% decrease in TV; ≥20% increase in TV, progressive disease; and non-PR/progressive disease, stable disease (SD). Event-free survival was defined as time for tumor doubling (EFS-2). Of 21 PDX models tested, 11 had significant prolongation of EFS-2 with elimusertib monotherapy. …

Inhibition Of Mcl-1 And Mek Overcomes Mek Inhibitor Resistance In Triple-Negative And Inflammatory Breast Cancers, Mohd Mughees, Moises Tacam, Alex W Tan, Mary Kathryn Pitner, Lakesla R Iles, Xiaoding Hu, Emilly S Villodre, Bisrat G Debeb, Takahiro Kogawa, Bora Lim, Rachel M Layman, Wendy A Woodward, Naoto T Ueno, Debu Tripathy, Savitri Krishnamurthy, Yuan Qi, Lajos Pusztai, Jian Wang, Varsha Gandhi, Geoffrey Bartholomeusz, Chandra Bartholomeusz

Faculty, Staff and Student Publications

The MAPK pathway can drive resistance in highly aggressive breast cancers. Our previous work showed that the MEK inhibitor (MEKi) AZD6244 (selumetinib) prevented lung metastasis in a breast cancer xenograft model. In clinical studies, MEKis as single agents have had only modest activity against solid tumors due to the onset of resistance. Using synthetic lethality siRNA screening, we identified myeloid cell leukemia-1 (MCL-1) as a potential contributor to AZD6244 resistance. We hypothesized that MCL-1 promotes MEKi resistance in highly aggressive breast cancers and that MCL-1 inhibition overcomes AZD6244 resistance. We established two AZD6244-resistant cell lines: MDA-MB-231-R (triple-negative breast cancer) and …

Commensal Colonization Of Candida Albicans In The Mouse Gastrointestinal Tract Is Mediated Via Expression Of Candidalysin And Adhesins, Kelsey E Mauk, Pedro Miramón, Michael C Lorenz, Léa Lortal, Julian R Naglik, Bernhard Hube, Lynn Bimler, Farrah Kheradmand, David B Corry

Faculty, Staff and Students Publications

The ubiquitous fungal pathogen Candida albicans has the potential to either asymptomatically colonize the gastrointestinal (GI) tract or become an invasive pathogen through mechanisms that remain incompletely understood. Here we explored the fungal, host, and environmental factors that influence the ability of C. albicans to colonize the mouse GI tract using a representative clinical strain, CLCA10. After a single gavage challenge (5 × 106 CFU C. albicans), specific pathogen-free (SPF) mice remained colonized with C. albicans strain CLCA10, but not other Candida species, for at least 58 days with the fungus confined largely to the gut luminal …

Targeting Aldh16a1 Mediated Thioredoxin Lysosomal Degradation To Enhance Ferroptosis Susceptibility In Smarca4-Deficient Nsclc, Guoshu Bi, Jiaqi Liang, Yunyi Bian, Guangyao Shan, Shencheng Ren, Haochun Shi, Xiaolong Huang, Junkan Zhu, Qun Wang, Wei Jiang, Boyi Gan, Cheng Zhan

Faculty, Staff and Student Publications

Ferroptosis, an iron-dependent form of cell death, holds promise for cancer therapy. However, the intricate link between ferroptosis and oncogenic mutations remains unclear. Here we show that SMARCA4, a well-established tumour suppressor whose deficiency is associated with poor prognosis and resistance to treatments, sensitizes non-small cell lung cancer (NSCLC) cells to ferroptosis. Mechanistically, SMARCA4 promotes chromatin accessibility and expression of ALDH16A1. Surprisingly, ALDH16A1 lacks ALDH enzymatic activity, but binds to the anti-ferroptotic oxidoreductase thioredoxin (TXN), facilitating its translocation to the lysosome and subsequent degradation. Meanwhile, ALDH16A1 directly inhibits TXN's oxidoreductase function by occluding its active site. We also show that …

Role Of Exchange Proteins Directly Activated By Camp Signaling In Vascular Remodeling, Xiaodong Cheng, Hua Liu, Wenbo Zhang, Wenli Yang, Fang Mei

Faculty, Staff and Student Publications

Vascular remodeling is a complex process involving the coordinated actions of multiple cellular signaling pathways in various cell types, leading to structural and functional changes in blood vessels. These changes can be adaptive, as in wound healing, or maladaptive, as seen in chronic vascular diseases such as atherosclerosis, hypertension, and retinopathy. Exchange proteins directly activated by cAMP (EPACs) are key players in cAMP-mediated cell signaling, distinct from the more traditionally studied protein kinase A pathway. EPAC proteins are guanine nucleotide exchange factors for the small G proteins Rap1 and Rap2. Recent studies have also revealed noncanonical functions of EPAC1 involving …

Secretogranin 2 Binds Lilrb4 Resulting In Immunosuppression, Xing Yang, Ryan Huang, Meng Fang, Yubo He, Jingjing Xie, Xiaoye Liu, Chengcheng Zhang, Qi Lou, Mi Deng, Wei Xiong, Cheryl Lewis, Zade Sadek, Ankit Gupta, Lianqi Chen, Xuewu Zhang, Lei Guo, Lin Xu, Ningyan Zhang, Zhiqiang An, Cheng Cheng Zhang

Faculty, Staff and Student Publications

Immunosuppressive myeloid cells are important in a variety of physiological and pathological contexts, including tumor development, but how hormones might regulate their activity is unclear. Secretogranins, a family of secretory proteins in endocrine and neuronal cells, are proposed to function as prohormones or hormones, but their specific receptors are unknown. Here we show that secretogranin 2 (SCG2), a granin family member, functionally interacts with leukocyte immunoglobulin-like receptor B4 (LILRB4) on monocytic cells. Tumor-derived SCG2 promotes tumor growth in myeloid-specific LILRB4 transgenic mice in a T cell-dependent manner, whereas SCG2 deficiency in host mice impairs tumor progression and reduces infiltration of …