Medical Specialties Commons^™

Spliceosome-Targeted Therapies Trigger An Antiviral Immune Response In Triple-Negative Breast Cancer, Elizabeth A Bowling, Jarey H Wang, Fade Gong, William Wu, Nicholas J Neill, Ik Sun Kim, Siddhartha Tyagi, Mayra Orellana, Sarah J Kurley, Rocio Dominguez-Vidaña, Hsiang-Ching Chung, Tiffany Y-T Hsu, Julien Dubrulle, Alexander B Saltzman, Heyuan Li, Jitendra K Meena, Gino M Canlas, Srinivas Chamakuri, Swarnima Singh, Lukas M Simon, Calla M Olson, Lacey E Dobrolecki, Michael T Lewis, Bing Zhang, Ido Golding, Jeffrey M Rosen, Damian W Young, Anna Malovannaya, Fabio Stossi, George Miles, Matthew J Ellis, Lihua Yu, Silvia Buonamici, Charles Y Lin, Kristen L Karlin, Xiang H-F Zhang, Thomas F Westbrook

Faculty, Staff and Students Publications

Many oncogenic insults deregulate RNA splicing, often leading to hypersensitivity of tumors to spliceosome-targeted therapies (STTs). However, the mechanisms by which STTs selectively kill cancers remain largely unknown. Herein, we discover that mis-spliced RNA itself is a molecular trigger for tumor killing through viral mimicry. In MYC-driven triple-negative breast cancer, STTs cause widespread cytoplasmic accumulation of mis-spliced mRNAs, many of which form double-stranded structures. Double-stranded RNA (dsRNA)-binding proteins recognize these endogenous dsRNAs, triggering antiviral signaling and extrinsic apoptosis. In immune-competent models of breast cancer, STTs cause tumor cell-intrinsic antiviral signaling, downstream adaptive immune signaling, and tumor cell death. Furthermore, RNA …

Mir-9-1 Suppresses Cell Proliferation And Promotes Apoptosis By Targeting Uhrf1 In Lung Cancer, Cheng-You Jia, Wei Xiang, Ji-Bin Liu, Geng-Xi Jiang, Feng Sun, Jian-Jun Wu, Xiao-Li Yang, Rui Xin, Yi Shi, Dan-Dan Zhang, Wen Li, Zavuga Zuberi, Jie Zhang, Gai-Xia Lu, Hui-Min Wang, Pei-Yao Wang, Fei Yu, Zhong-Wei Lv, Yu-Shui Ma, Da Fu

Faculty, Staff and Student Publications

Lung cancer is listed as the most common reason for cancer-related death all over the world despite diagnostic improvements and the development of chemotherapy and targeted therapies. MicroRNAs control both physiological and pathological processes including development and cancer. A microRNA-9 to 1 (miR-9 to 1) overexpression model in lung cancer cell lines was established and miR-9 to 1 was found to significantly suppress the proliferation rate in lung cancer cell lines, colony formation in vitro, and tumorigenicity in nude mice of A549 cells. Ubiquitin-like containing PHD and RING finger domains 1 (UHRF1) was then identified to direct target of miR-9 …

Large-Scale Characterization Of Drug Responses Of Clinically Relevant Proteins In Cancer Cell Lines, Wei Zhao, Jun Li, Mei-Ju M Chen, Yikai Luo, Zhenlin Ju, Nicole K Nesser, Katie Johnson-Camacho, Christopher T Boniface, Yancey Lawrence, Nupur T Pande, Michael A Davies, Meenhard Herlyn, Taru Muranen, Ioannis K Zervantonakis, Erika Von Euw, Andre Schultz, Shwetha V Kumar, Anil Korkut, Paul T Spellman, Rehan Akbani, Dennis J Slamon, Joe W Gray, Joan S Brugge, Yiling Lu, Gordon B Mills, Han Liang

Faculty, Staff and Students Publications

Perturbation biology is a powerful approach to modeling quantitative cellular behaviors and understanding detailed disease mechanisms. However, large-scale protein response resources of cancer cell lines to perturbations are not available, resulting in a critical knowledge gap. Here we generated and compiled perturbed expression profiles of ∼210 clinically relevant proteins in >12,000 cancer cell line samples in response to ∼170 drug compounds using reverse-phase protein arrays. We show that integrating perturbed protein response signals provides mechanistic insights into drug resistance, increases the predictive power for drug sensitivity, and helps identify effective drug combinations. We build a systematic map of "protein-drug" connectivity …

Role For Carbohydrate Response Element-Binding Protein (Chrebp) In High Glucose-Mediated Repression Of Long Noncoding Rna Tug1, Jianyin Long, Daniel L Galvan, Koki Mise, Yashpal S Kanwar, Li Li, Naravat Poungavrin, Paul A Overbeek, Benny H Chang, Farhad R Danesh

Faculty, Staff and Students Publications

Long noncoding RNAs (lncRNAs) have been shown to play key roles in a variety of biological activities of the cell. However, less is known about how lncRNAs respond to environmental cues and what transcriptional mechanisms regulate their expression. Studies from our laboratory have shown that the lncRNA Tug1 (taurine upregulated gene 1) is crucial for the progression of diabetic kidney disease, a major microvascular complication of diabetes. Using a combination of proximity labeling with the engineered soybean ascorbate peroxidase (APEX2), ChIP-qPCR, biotin-labeled oligonucleotide pulldown, and classical promoter luciferase assays in kidney podocytes, we extend our initial observations in the current …

Combating Acquired Resistance To Mapk Inhibitors In Melanoma By Targeting Abl1/2-Mediated Reactivation Of Mek/Erk/Myc Signaling., Rakshamani Tripathi, Zulong Liu, Aditi Jain,, Anastasia Lyon, Christina Meeks, Dana Richards, Jinpeng Liu, Daheng He, Chi Wang, Marika Nespi, Andrey Rymar, Peng Wang, Melissa Wilson, Rina Plattner

Department of Medical Oncology Faculty Papers

Metastatic melanoma remains an incurable disease for many patients due to the limited success of targeted and immunotherapies. BRAF and MEK inhibitors reduce metastatic burden for patients with melanomas harboring BRAF mutations; however, most eventually relapse due to acquired resistance. Here, we demonstrate that ABL1/2 kinase activities and/or expression are potentiated in cell lines and patient samples following resistance, and ABL1/2 drive BRAF and BRAF/MEK inhibitor resistance by inducing reactivation of MEK/ERK/MYC signaling. Silencing/inhibiting ABL1/2 blocks pathway reactivation, and resensitizes resistant cells to BRAF/MEK inhibitors, whereas expression of constitutively active ABL1/2 is sufficient to promote resistance. Significantly, nilotinib (2^{nd …}

Atrial Myocyte Nlrp3/Camkii Nexus Forms A Substrate For Postoperative Atrial Fibrillation, Jordi Heijman, Azinwi Phina Muna, Tina Veleva, Cristina E Molina, Henry Sutanto, Marcel Tekook, Qiongling Wang, Issam H Abu-Taha, Marcel Gorka, Stephan Künzel, Ali El-Armouche, Hermann Reichenspurner, Markus Kamler, Viacheslav Nikolaev, Ursula Ravens, Na Li, Stanley Nattel, Xander H T Wehrens, Dobromir Dobrev

Faculty, Staff and Students Publications

RATIONALE: Postoperative atrial fibrillation (POAF) is a common and troublesome complication of cardiac surgery. POAF is generally believed to occur when postoperative triggers act on a preexisting vulnerable substrate, but the underlying cellular and molecular mechanisms are largely unknown.

OBJECTIVE: To identify cellular POAF mechanisms in right atrial samples from patients without a history of atrial fibrillation undergoing open-heart surgery.

METHODS AND RESULTS: Multicellular action potentials, membrane ion-currents (perforated patch-clamp), or simultaneous membrane-current (ruptured patch-clamp) and [Ca

CONCLUSIONS: Preexisting Ca

Long Noncoding Rna H19x Is A Key Mediator Of Tgf-Β-Driven Fibrosi, Elena Pachera, Shervin Assassi, Gloria A Salazar, Mara Stellato, Florian Renoux, Adam Wunderlin, Przemyslaw Blyszczuk, Robert Lafyatis, Fina Kurreeman, Jeska De Vries-Bouwstra, Tobias Messemaker, Carol A Feghali-Bostwick, Gerhard Rogler, Wouter T Van Haaften, Gerard Dijkstra, Fiona Oakley, Maurizio Calcagni, Janine Schniering, Britta Maurer, Jörg Hw Distler, Gabriela Kania, Mojca Frank-Bertoncelj, Oliver Distler

Faculty, Staff and Student Publications

TGF-β is a master regulator of fibrosis, driving the differentiation of fibroblasts into apoptosis-resistant myofibroblasts and sustaining the production of extracellular matrix (ECM) components. Here, we identified the nuclear long noncoding RNA (lncRNA) H19X as a master regulator of TGF-β-driven tissue fibrosis. H19X was consistently upregulated in a wide variety of human fibrotic tissues and diseases and was strongly induced by TGF-β, particularly in fibroblasts and fibroblast-related cells. Functional experiments following H19X silencing revealed that H19X was an obligatory factor for TGF-β-induced ECM synthesis as well as differentiation and survival of ECM-producing myofibroblasts. We showed that H19X regulates DDIT4L gene …

The Landscape Of Rna Polymerase Ii-Associated Chromatin Interactions In Prostate Cancer, Susmita G Ramanand, Yong Chen, Jiapei Yuan, Kelly Daescu, Maryou Bk Lambros, Kathleen E Houlahan, Suzanne Carreira, Wei Yuan, Guemhee Baek, Adam Sharp, Alec Paschalis, Mohammed Kanchwala, Yunpeng Gao, Adam Aslam, Nida Safdar, Xiaowei Zhan, Ganesh V Raj, Chao Xing, Paul C Boutros, Johann De Bono, Michael Q Zhang, Ram S Mani

College of Science & Mathematics Departmental Research

Transcriptional dysregulation is a hallmark of prostate cancer (PCa). We mapped the RNA polymerase II-associated (RNA Pol II-associated) chromatin interactions in normal prostate cells and PCa cells. We discovered thousands of enhancer-promoter, enhancer-enhancer, as well as promoter-promoter chromatin interactions. These transcriptional hubs operate within the framework set by structural proteins - CTCF and cohesins - and are regulated by the cooperative action of master transcription factors, such as the androgen receptor (AR) and FOXA1. By combining analyses from metastatic castration-resistant PCa (mCRPC) specimens, we show that AR locus amplification contributes to the transcriptional upregulation of the AR gene by increasing …

A Substitution In Cgmp-Dependent Protein Kinase 1 Associated With Aortic Disease Induces An Active Conformation In The Absence Of Cgmp, Matthew H Chan, Sahar Aminzai, Tingfei Hu, Amatya Taran, Sheng Li, Choel Kim, Renate B Pilz, Darren E Casteel

Faculty, Staff and Students Publications

Type 1 cGMP-dependent protein kinases (PKGs) play important roles in human cardiovascular physiology, regulating vascular tone and smooth-muscle cell phenotype. A mutation in the human PRKG1 gene encoding cGMP-dependent protein kinase 1 (PKG1) leads to thoracic aortic aneurysms and dissections. The mutation causes an arginine-to-glutamine (RQ) substitution within the first cGMP-binding pocket in PKG1. This substitution disrupts cGMP binding to the pocket, but it also unexpectedly causes PKG1 to have high activity in the absence of cGMP via an unknown mechanism. Here, we identified the molecular mechanism whereby the RQ mutation increases basal kinase activity in the human PKG1α and …

Rna-Gps Predicts High-Resolution Rna Subcellular Localization And Highlights The Role Of Splicing, Kevin E Wu, Kevin R Parker, Furqan M Fazal, Howard Y Chang, James Zou

Faculty, Staff and Students Publications

Subcellular localization is essential to RNA biogenesis, processing, and function across the gene expression life cycle. However, the specific nucleotide sequence motifs that direct RNA localization are incompletely understood. Fortunately, new sequencing technologies have provided transcriptome-wide atlases of RNA localization, creating an opportunity to leverage computational modeling. Here we present RNA-GPS, a new machine learning model that uses nucleotide-level features to predict RNA localization across eight different subcellular locations-the first to provide such a wide range of predictions. RNA-GPS's design enables high-throughput sequence ablation and feature importance analyses to probe the sequence motifs that drive localization prediction. We find localization …

Discovery Of A Selective Inhibitor Of Doublecortin Like Kinase 1, Fleur M Ferguson, Behnam Nabet, Srivatsan Raghavan, Yan Liu, Alan L Leggett, Miljan Kuljanin, Radha L Kalekar, Annan Yang, Shuning He, Jinhua Wang, Raymond W S Ng, Rita Sulahian, Lianbo Li, Emily J Poulin, Ling Huang, Jost Koren, Nora Dieguez-Martinez, Sergio Espinosa, Zhiyang Zeng, Cesear R Corona, James D Vasta, Ryoma Ohi, Taebo Sim, Nam Doo Kim, Wayne Harshbarger, Jose M Lizcano, Matthew B Robers, Senthil Muthaswamy, Charles Y Lin, A Thomas Look, Kevin M Haigis, Joseph D Mancias, Brian M Wolpin, Andrew J Aguirre, William C Hahn, Kenneth D Westover, Nathanael S Gray

Faculty, Staff and Students Publications

Doublecortin like kinase 1 (DCLK1) is an understudied kinase that is upregulated in a wide range of cancers, including pancreatic ductal adenocarcinoma (PDAC). However, little is known about its potential as a therapeutic target. We used chemoproteomic profiling and structure-based design to develop a selective, in vivo-compatible chemical probe of the DCLK1 kinase domain, DCLK1-IN-1. We demonstrate activity of DCLK1-IN-1 against clinically relevant patient-derived PDAC organoid models and use a combination of RNA-sequencing, proteomics and phosphoproteomics analysis to reveal that DCLK1 inhibition modulates proteins and pathways associated with cell motility in this context. DCLK1-IN-1 will serve as a versatile tool …

Myeloma Cells Shift Osteoblastogenesis To Adipogenesis By Inhibiting The Ubiquitin Ligase Murf1 In Mesenchymal Stem Cells, Zhiqiang Liu, Huan Liu, Jin He, Pei Lin, Qiang Tong, Jing Yang

Faculty, Staff and Students Publications

The suppression of bone formation is a hallmark of multiple myeloma. Myeloma cells inhibit osteoblastogenesis from mesenchymal stem cells (MSCs), which can also differentiate into adipocytes. We investigated myeloma-MSC interactions and the effects of such interactions on the differentiation of MSCs into adipocytes or osteoblasts using single-cell RNA sequencing, in vitro co-culture, and subcutaneous injection of MSCs and myeloma cells into mice. Our results revealed that the α4 subunit of integrin on myeloma cells stimulated vascular cell adhesion molecule 1 (VCAM1) on MSCs, leading to the activation of protein kinase C β1 (PKCβ1) signaling and repression of the muscle ring-finger …

Ubiquitination Of The Dna-Damage Checkpoint Kinase Chk1 By Traf4 Is Required For Chk1 Activation, Xinfang Yu, Wei Li, Haidan Liu, Qipan Deng, Xu Wang, Hui Hu, Zijun Y Xu-Monette, Wei Xiong, Zhongxin Lu, Ken H Young, Wei Wang, Yong Li

Faculty, Staff and Students Publications

BACKGROUND: Aberrant activation of DNA damage response (DDR) is a major cause of chemoresistance in colorectal cancer (CRC). CHK1 is upregulated in CRC and contributes to therapeutic resistance. We investigated the upstream signaling pathways governing CHK1 activation in CRC.

METHODS: We identified CHK1-binding proteins by mass spectrometry analysis. We analyzed the biologic consequences of knockout or overexpression of TRAF4 using immunoblotting, immunoprecipitation, and immunofluorescence. CHK1 and TRAF4 ubiquitination was studied in vitro and in vivo. We tested the functions of TRAF4 in CHK1 phosphorylation and CRC chemoresistance by measuring cell viability and proliferation, anchorage-dependent and -independent cell growth, and mouse …

Discovery Of A Bacterial Peptide As A Modulator Of Glp-1 And Metabolic Disease, Catherine Tomaro-Duchesneau, Stephanie L Levalley, Daniel Roeth, Liang Sun, Frank T Horrigan, Markus Kalkum, Joseph M Hyser, Robert A Britton

Faculty, Staff and Students Publications

Early work in rodents highlighted the gut microbiota's importance in metabolic disease, including Type II Diabetes Mellitus (T2DM) and obesity. Glucagon-like peptide-1 (GLP-1), an incretin secreted by L-cells lining the gastrointestinal epithelium, has important functions: promoting insulin secretion, insulin sensitivity, and β-cell mass, while inhibiting gastric emptying and appetite. We set out to identify microbial strains with GLP-1 stimulatory activity as potential metabolic disease therapeutics. Over 1500 human-derived strains were isolated from healthy individuals and screened for GLP-1 modulation by incubating bacterial cell-free supernatants with NCI H716 L-cells. Approximately 45 strains capable of increasing GLP-1 were discovered. All GLP-1 positive …

The Sineb1 Element In The Long Non-Coding Rna Malat1 Is Necessary For Tdp-43 Proteostasis, Tuan M Nguyen, Elena B Kabotyanski, Lucas C Reineke, Jiaofang Shao, Feng Xiong, Joo-Hyung Lee, Julien Dubrulle, Hannah Johnson, Fabio Stossi, Phoebe S Tsoi, Kyoung-Jae Choi, Alexander G Ellis, Na Zhao, Jin Cao, Oluwatoyosi Adewunmi, Josephine C Ferreon, Allan Chris M Ferreon, Joel R Neilson, Michael A Mancini, Xi Chen, Jongchan Kim, Li Ma, Wenbo Li, Jeffrey M Rosen

Faculty, Staff and Students Publications

Transposable elements (TEs) comprise a large proportion of long non-coding RNAs (lncRNAs). Here, we employed CRISPR to delete a short interspersed nuclear element (SINE) in Malat1, a cancer-associated lncRNA, to investigate its significance in cellular physiology. We show that Malat1 with a SINE deletion forms diffuse nuclear speckles and is frequently translocated to the cytoplasm. SINE-deleted cells exhibit an activated unfolded protein response and PKR and markedly increased DNA damage and apoptosis caused by dysregulation of TDP-43 localization and formation of cytotoxic inclusions. TDP-43 binds stronger to Malat1 without the SINE and is likely 'hijacked' by cytoplasmic Malat1 to the …

A Broad-Spectrum Antiviral Molecule, Ql47, Selectively Inhibits Eukaryotic Translation, Mélissanne De Wispelaere, Margot Carocci, Dominique J Burri, William J Neidermyer, Calla M Olson, Imme Roggenbach, Yanke Liang, Jinhua Wang, Sean P J Whelan, Nathanael S Gray, Priscilla L Yang

Faculty, Staff and Students Publications

Small-molecule inhibitors of translation are critical tools to study the molecular mechanisms of protein synthesis. In this study, we sought to characterize how QL47, a host-targeted, small-molecule antiviral agent, inhibits steady-state viral protein expression. We demonstrate that this small molecule broadly inhibits both viral and host protein synthesis and targets a translation step specific to eukaryotic cells. We show that QL47 inhibits protein neosynthesis initiated by both canonical cap-driven and noncanonical initiation strategies, most likely by targeting an early step in translation elongation. Our findings thus establish QL47 as a new small-molecule inhibitor that can be utilized to probe the …

The Mitochondrial Hsp90 Paralog Trap1 Forms An Oxphos-Regulated Tetramer And Is Involved In Mitochondrial Metabolic Homeostasis, Abhinav Joshi, Li Dai, Yanxin Liu, Jungsoon Lee, Nastaran Mohammadi Ghahhari, Gregory Segala, Kristin Beebe, Lisa M Jenkins, Gaelyn C Lyons, Lilia Bernasconi, Francis T F Tsai, David A Agard, Len Neckers, Didier Picard

Faculty, Staff and Students Publications

BACKGROUND: The molecular chaperone TRAP1, the mitochondrial isoform of cytosolic HSP90, remains poorly understood with respect to its pivotal role in the regulation of mitochondrial metabolism. Most studies have found it to be an inhibitor of mitochondrial oxidative phosphorylation (OXPHOS) and an inducer of the Warburg phenotype of cancer cells. However, others have reported the opposite, and there is no consensus on the relevant TRAP1 interactors. This calls for a more comprehensive analysis of the TRAP1 interactome and of how TRAP1 and mitochondrial metabolism mutually affect each other.

RESULTS: We show that the disruption of the gene for TRAP1 in …

Development And Characterization Of A Wee1 Kinase Degrader, Zhengnian Li, Benika J Pinch, Calla M Olson, Katherine A Donovan, Radosław P Nowak, Caitlin E Mills, David A Scott, Zainab M Doctor, Nicholas A Eleuteri, Mirra Chung, Peter K Sorger, Eric S Fischer, Nathanael S Gray

Faculty, Staff and Students Publications

The G1/S cell cycle checkpoint is frequently dysregulated in cancer, leaving cancer cells reliant on a functional G2/M checkpoint to prevent excessive DNA damage. Wee1 regulates the G2/M checkpoint by phosphorylating CDK1 at Tyr15 to prevent mitotic entry. Previous drug development efforts targeting Wee1 resulted in the clinical-grade inhibitor, AZD1775. However, AZD1775 is burdened by dose-limiting adverse events, and has off-target PLK1 activity. In an attempt to overcome these limitations, we developed Wee1 degraders by conjugating AZD1775 to the cereblon (CRBN)-binding ligand, pomalidomide. The resulting lead compound, ZNL-02-096, degrades Wee1 while sparing PLK1, induces G2/M accumulation at 10-fold lower doses …

Targeting The Tumor Core: Hypoxia-Responsive Nanoparticles For The Delivery Of Chemotherapy To Pancreatic Tumors, Matthew I. Confeld, Babak Mamnoon, Li Feng, Heather Jensen Smith, Priyanka Ray, James Froberg, Jiha Kim, Michael A. Hollingsworth, Mohiuddin Quadir, Yongki Choi, Sanku Mallik

Journal Articles: Eppley Institute

In pancreatic ductal adenocarcinoma (PDAC), early onset of hypoxia triggers remodeling of the extracellular matrix, epithelial-to-mesenchymal transition, increased cell survival, the formation of cancer stem cells, and drug resistance. Hypoxia in PDAC is also associated with the development of collagen-rich, fibrous extracellular stroma (desmoplasia), resulting in severely impaired drug penetration. To overcome these daunting challenges, we created polymer nanoparticles (polymersomes) that target and penetrate pancreatic tumors, reach the hypoxic niches, undergo rapid structural destabilization, and release the encapsulated drugs. In vitro studies indicated a high cellular uptake of the polymersomes and increased cytotoxicity of the drugs under hypoxia compared to …

Sirt3 Promotes Lipophagy And Chaperon-Mediated Autophagy To Protect Hepatocytes Against Lipotoxicity, Tian Zhang, Jingxin Liu, Shengnan Shen, Qiang Tong, Xiaojun Ma, Ligen Lin

Faculty, Staff and Students Publications

Lipophagy is a lysosomal lipolytic pathway that complements the actions of cytosolic neutral lipases. Chaperon-mediated autophagy (CMA) triggers lipid droplets (LDs) breakdown, to initiate lipolysis via either cytosolic lipases or macroautophagy. SIRT3, a mitochondrial NAD+-dependent deacetylase, regulates the acetylation status and activity of many substrates involving in energy metabolism. However, the role of SIRT3 in regulating lipophagy is controversial. The current study showed that SIRT3 expression was decreased and the macroautophagy flux was blocked in the primary hepatocytes from high-fat diet fed mice and P/O (palmitic acid and oleic acid mixture) treated AML12 mouse hepatocytes, compared with the corresponding controls. …

Examining Multiple Cellular Pathways At Once Using Multiplex Hextuple Luciferase Assaying, Alejandro Sarrion-Perdigones, Lyra Chang, Yezabel Gonzalez, Tatiana Gallego-Flores, Damian W Young, Koen J T Venken

Faculty, Staff and Students Publications

Sensitive simultaneous assessment of multiple signaling pathways within the same cells requires orthogonal reporters that can assay over large dynamic ranges. Luciferases are such genetically encoded candidates due to their sensitivity, versatility, and cost-effectiveness. We expand luciferase multiplexing in post-lysis endpoint luciferase assays from two to six. Light emissions are distinguished by a combination of distinct substrates and emission spectra deconvolution. All six luciferase reporter units are stitched together into one plasmid facilitating delivery of all reporter units through a process we termed solotransfection, minimizing experimental errors. We engineer a multiplex hextuple luciferase assay to probe pathway fluxes through five …

Sirna Targeting And Treatment Of Gastrointestinal Diseases., Rachel Chevalier

Manuscripts, Articles, Book Chapters and Other Papers

RNA interference via small interfering RNA (siRNA) offers opportunities to precisely target genes that contribute to gastrointestinal (GI) pathologies, such as inflammatory bowel disease, celiac, and esophageal scarring. Delivering the siRNA to the GI tract proves challenging as the harsh environment of the intestines degrades the siRNA before it can reach its target or blocks its entry into its site of action in the cytoplasm. Additionally, the GI tract is large and disease is often localized to a specific site. This review discusses polymer and lipid-based delivery systems for protection and targeting of siRNA therapies to the GI tract to …

Steroid Receptor Coactivator-1 Modulates The Function Of Pomc Neurons And Energy Homeostasis, Yongjie Yang, Agatha A Van Der Klaauw, Liangru Zhu, Tessa M Cacciottolo, Yanlin He, Lukas K J Stadler, Chunmei Wang, Pingwen Xu, Kenji Saito, Antentor Hinton, Xiaofeng Yan, Julia M Keogh, Elana Henning, Matthew C Banton, Audrey E Hendricks, Elena G Bochukova, Vanisha Mistry, Katherine L Lawler, Lan Liao, Jianming Xu, Stephen O'Rahilly, Qingchun Tong, Uk10k Consortium, Inês Barroso, Bert W O'Malley, I Sadaf Farooqi, Yong Xu

Children’s Nutrition Research Center Staff Publications

Hypothalamic neurons expressing the anorectic peptide Pro-opiomelanocortin (Pomc) regulate food intake and body weight. Here, we show that Steroid Receptor Coactivator-1 (SRC-1) interacts with a target of leptin receptor activation, phosphorylated STAT3, to potentiate Pomc transcription. Deletion of SRC-1 in Pomc neurons in mice attenuates their depolarization by leptin, decreases Pomc expression and increases food intake leading to high-fat diet-induced obesity. In humans, fifteen rare heterozygous variants in SRC-1 found in severely obese individuals impair leptin-mediated Pomc reporter activity in cells, whilst four variants found in non-obese controls do not. In a knock-in mouse model of a loss of function …

Proteomic Alterations Of Hdl In Youth With Type 1 Diabetes And Their Associations With Glycemic Control: A Case-Control Study, Evgenia Gourgari, Junfeng Ma, Martin P. Playford, Nehal N. Mehta, Radoslav Goldman, Alan T. Remaley, Scott M. Gordon

Saha Cardiovascular Research Center Faculty Publications

Background: Patients with type 1 diabetes (T1DM) typically have normal or even elevated plasma high density lipoprotein (HDL) cholesterol concentrations; however, HDL protein composition can be altered without a change in cholesterol content. Alteration of the HDL proteome can result in dysfunctional HDL particles with reduced ability to protect against cardiovascular disease (CVD). The objective of this study was to compare the HDL proteomes of youth with T1DM and healthy controls (HC) and to evaluate the influence of glycemic control on HDL protein composition.

Methods: This was a cross-sectional case–control study. Blood samples were obtained from patients with T1DM and …

Alterations In Phosphorylation Of Hepatocyte Ribosomal Protein S6 Control Plasmodium Liver Stage Infection., Elizabeth K K Glennon, Laura S Austin, Nadia Arang, Heather S Kain, Fred D Mast, Kamalakannan Vijayan, John D Aitchison, Stefan H I Kappe, Alexis Kaushansky

Articles, Abstracts, and Reports

Plasmodium parasites are highly selective when infecting hepatocytes and induce many changes within the host cell upon infection. While several host cell factors have been identified that are important for liver infection, our understanding of what facilitates the maintenance of infection remains incomplete. Here, we describe a role for phosphorylated ribosomal protein S6 (Ser235/236) (p-RPS6) in Plasmodium yoelii-infected hepatocytes. Blocking RPS6 phosphorylation prior to infection decreases the number of liver stage parasites within 24 h. Infected hepatocytes exhibit elevated levels of p-RPS6 while simultaneously abrogating the induction of phosphorylation of RPS6 in response to insulin stimulation. This is in contrast …

The Mitochondrial Deoxyguanosine Kinase Is Required For Cancer Cell Stemness In Lung Adenocarcinoma, Shengchen Lin, Chongbiao Huang, Jianwei Sun, Oana Bollt, Xiuchao Wang, Eric Martine, Jiaxin Kang, Matthew D. Taylor, Bin Fang, Pankaj K. Singh, John Koomen, Jihui Hao, Shengyu Yang

Journal Articles: Eppley Institute

The mitochondrial deoxynucleotide triphosphate (dNTP) is maintained by the mitochondrial deoxynucleoside salvage pathway and dedicated for the mtDNA homeostasis, and the mitochondrial deoxyguanosine kinase (DGUOK) is a rate-limiting enzyme in this pathway. Here, we investigated the role of the DGUOK in the self-renewal of lung cancer stem-like cells (CSC). Our data support that DGUOK overexpression strongly correlates with cancer progression and patient survival. The depletion of DGUOK robustly inhibited lung adenocarcinoma tumor growth, metastasis, and CSC self-renewal. Mechanistically, DGUOK is required for the biogenesis of respiratory complex I and mitochondrial OXPHOS, which in turn regulates CSC self-renewal through AMPK-YAP1 signaling. …

Inhibition Of Geranylgeranyl Diphosphate Synthase Is A Novel Therapeutic Strategy For Pancreatic Ductal Adenocarcinoma, Staci L. Haney, Michelle L. Varney, Yashpal S. Chhonker, Simon Shin, Kamiya Mehla, Ayrianne J. Crawford, Heather Jensen Smith, Lynette M. Smith, Daryl J. Murry, Michael A. Hollingsworth, Sarah A. Holstein

Journal Articles: Eppley Institute

Rab proteins play an essential role in regulating intracellular membrane trafficking processes. Rab activity is dependent upon geranylgeranylation, a post-translational modification that involves the addition of 20-carbon isoprenoid chains via the enzyme geranylgeranyl transferase (GGTase) II. We have focused on the development of inhibitors against geranylgeranyl diphosphate synthase (GGDPS), which generates the isoprenoid donor (GGPP), as anti-Rab agents. Pancreatic ductal adenocarcinoma (PDAC) is characterized by abnormal mucin production and these mucins play important roles in tumor development, metastasis and chemo-resistance. We hypothesized that GGDPS inhibitor (GGDPSi) treatment would induce PDAC cell death by disrupting mucin trafficking, thereby inducing the unfolded …

Melatonin Enhances Sorafenib-Induced Cytotoxicity In Flt3-Itd Acute Myeloid Leukemia Cells By Redox Modification, Tian Tian, Jiajun Li, Yizhuo Li, Yun-Xin Lu, Yan-Lai Tang, Hua Wang, Fufu Zheng, Dingbo Shi, Qian Long, Miao Chen, Guillermo Garcia-Manero, Yumin Hu, Lijun Qin, Wuguo Deng

Faculty, Staff and Student Publications

Acute myeloid leukemia (AML) with an internal tandem duplication in Fms-related tyrosine kinase 3 (FLT3-ITD) is identified as a subgroup with poor outcome and intrinsic resistance to chemotherapy and therefore urgent need for development of novel therapeutic strategies.

Methods: The antitumor effects of melatonin alone or combined with sorafenib were evaluated via flow cytometry and immunoblotting assays in FLT-ITD AML cells. Also, the ex vivo and in vivo models were used to test the synergistic effects of melatonin and sorafenib against leukemia with FLT3/ITD mutation.

Results: Our study shows for the first time that melatonin inhibits proliferation and induces apoptosis …

Collagen Prolyl 4-Hydroxylase 1 Is Essential For Hif-1Α Stabilization And Tnbc Chemoresistance, Gaofeng Xiong, Rachel L. Stewart, Jie Chen, Tianyan Gao, Timothy L. Scott, Luis M. Samayoa, Kathleen L. O'Connor, Andrew N. Lane, Ren Xu

Markey Cancer Center Faculty Publications

Collagen prolyl 4-hydroxylase (P4H) expression and collagen hydroxylation in cancer cells are necessary for breast cancer progression. Here, we show that P4H alpha 1 subunit (P4HA1) protein expression is induced in triple-negative breast cancer (TNBC) and HER2 positive breast cancer. By modulating alpha ketoglutarate (α-KG) and succinate levels P4HA1 expression reduces proline hydroxylation on hypoxia-inducible factor (HIF) 1α, enhancing its stability in cancer cells. Activation of the P4HA/HIF-1 axis enhances cancer cell stemness, accompanied by decreased oxidative phosphorylation and reactive oxygen species (ROS) levels. Inhibition of P4HA1 sensitizes TNBC to the chemotherapeutic agent docetaxel and doxorubicin in xenografts and patient-derived …

3,3'-Diindolylmethane Enhances Apoptosis In Docetaxel-Treated Breast Cancer Cells By Generation Of Reactive Oxygen Species., Susan Lanza-Jacoby, Guanjun Cheng

Department of Surgery Faculty Papers

CONTEXT: A major problem in the treatment of cancer is the development of toxic side effects and resistance to chemotherapy. The use of plant compounds to overcome resistance and prevent toxicity is a potential strategy for treatment.

OBJECTIVE: We evaluated whether 3,3'-diindolylmethane (DIM) enhanced the sensitivity of breast cancer cells to docetaxel (DOC).

MATERIALS AND METHODS: MDA-MB231 and Sk-BR-3 cells were treated with and without 25 or 50 µM of DIM and 1 nM of DOC for 48 and 72 h, respectively. MTT assay was used to measure cell survival. Apoptosis and intracellular reactive oxygen species (ROS) were determined by …