Digital Commons Network^™

Atomic Structure Of The Leishmania Spp Hsp100 N-Domain, Jonathan M Mercado, Sukyeong Lee, Changsoo Chang, Nuri Sung, Lynn Soong, Andre Catic, Francis T F Tsai

Faculty, Staff and Students Publications

Hsp100 is an ATP-dependent unfoldase that promotes protein disaggregation or facilitates the unfolding of aggregation-prone polypeptides marked for degradation. Recently, new Hsp100 functions are emerging. In Plasmodium, an Hsp100 drives malaria protein export, presenting a novel drug target. Whether Hsp100 has a similar function in other protists is unknown. We present the 1.06 Å resolution crystal structure of the Hsp100 N-domain from Leishmania spp., the causative agent of leishmaniasis in humans. Our structure reveals a network of methionines and aromatic amino acids that define the putative substrate-binding site and likely evolved to protect Hsp100 from oxidative damage in host immune …

A Novel Crosstalk Between Autophagosomes And Phagosomes That Facilitates The Clearance Of Apoptotic Cells, Zheng Zhou, Omar Peña-Ramos

Faculty, Staff and Students Publications

During an animal's life, many cells undergo apoptosis, a form of genetically programmed cell death. These cells are swiftly engulfed by other cells through phagocytosis and subsequently degraded inside phagosomes. Phagocytosis and macroautophagy/autophagy are two different cellular events: whereas phagocytosis is a cell-eat-cell event, autophagy, or "self-eating", occurs within one cell, resulting in the enveloping of protein aggregates or damaged organelles within double-membrane autophagosomes. Despite this critical difference, these two events share common features: (1) both are means of safe garbage disposal; (2) both phagosomes and autophagosomes fuse to lysosomes, which drive the degradation of their contents; and (3) both …

Evolution Of International Pediatric Endoscopic Practice Changes During The Coronavirus Disease 2019 Pandemic, Wenly Ruan, Douglas S Fishman, Diana G Lerner, Raoul I Furlano, Mike Thomson, Catharine M Walsh

Faculty, Staff and Students Publications

OBJECTIVES: The coronavirus disease 2019 (COVID-19) pandemic has drastically altered endoscopic practices. We initially reported the international impact of COVID-19 on pediatric endoscopic practice. This follow-up study aimed to assess changes 7 months following the initial survey to delineate practice change patterns as the pandemic evolved.

METHODS: Pediatric gastroenterologists who responded to the initial survey were re-surveyed seven months later using Research Electronic Data Capture (REDCap). The survey recorded information on changes in pediatric endoscopic practice patterns, including COVID-19 screening and testing processes and personal protective equipment (PPE) utilization. Additionally, endoscopists' risk tolerance of COVID-19 transmission was evaluated.

RESULTS: Seventy-five …

Co-Transmitting Neurons In The Lateral Septal Nucleus Exhibit Features Of Neurotransmitter Switching, Patrick J Hunt, Mikhail Kochukov, Brandon T Pekarek, Benjamin D W Belfort, Juan M Romero, Jessica L Swanson, Benjamin R Arenkiel

Faculty, Staff and Students Publications

The lateral septal nucleus (LSN) is a highly interconnected region of the central brain whose activity regulates widespread circuitry. As such, the mechanisms that govern neuronal activity within the LSN have far-reaching implications on numerous brain-wide nuclei, circuits, and behaviors. We found that GABAergic neurons within the LSN express markers that mediate the release of acetylcholine (ACh). Moreover, we show that these vGATLSN neurons release both GABA and ACh onto local glutamatergic LSN neurons. Using both short-term and long-term neuronal labeling techniques we observed expression of the cholinergic neuron marker Choline Acetyltransferase (ChAT) in vGATLSN neurons. These findings provide evidence …

Circadian Clock, Diurnal Glucose Metabolic Rhythm, And Dawn Phenomenon, Fei Peng, Xin Li, Fang Xiao, Ruxing Zhao, Zheng Sun

Faculty, Staff and Students Publications

The circadian clock provides cue-independent anticipatory signals for diurnal rhythms of baseline glucose levels and glucose tolerance. The central circadian clock is located in the hypothalamic suprachiasmatic nucleus (SCN), which comprises primarily GABAergic neurons. The SCN clock regulates physiological diurnal rhythms of endogenous glucose production (EGP) and hepatic insulin sensitivity through neurohumoral mechanisms. Disruption of the molecular circadian clock is associated with the extended dawn phenomenon (DP) in type 2 diabetes (T2D), referring to hyperglycemia in the early morning without nocturnal hypoglycemia. The DP affects nearly half of patients with diabetes, with poorly defined etiology and a lack of targeted …

Social And Demographic Disparities In The Severity Of Multisystem Inflammatory Syndrome In Children, Fabio Savorgnan, Sebastian Acosta, Alexander Alali, Axel Moreira, Ananth Annapragada, Craig G Rusin, Saul Flores, Rohit S Loomba, Alvaro Moreira

Faculty, Staff and Students Publications

Social constructs are known risk factors for multisystem inflammatory syndrome in children. A review of 206 patients demonstrated that children who were non-Hispanic Black, over the age of 12 years or living in a disadvantaged neighborhood associated with severe multisystem inflammatory syndrome in children (intensive care unit admission, intubation and/or vasopressor use).

Syphilis In The Esophagus, Ronan Allencherril, Paul Nicholls, Shilpa Jain, Robert Sealock, Priti Dangayach

Faculty, Staff and Students Publications

This report documents a unique case of syphilis with esophageal involvement. Such a presentation is exceedingly rare in the modern era, particularly among patients without human immunodeficiency virus. Most instances were documented in the 1900s and earlier. Our patient presented with months of odynophagia and recurrent oral lesions. He was found to have a sizeable esophageal ulcer on endoscopy, with biopsy confirming the diagnosis of syphilis. His symptoms quickly resolved with intramuscular penicillin. This case highlights the importance of keeping a broad differential for odynophagia and suspicious lesions, cutaneous or mucosal.

Impact Of A Rapid High-Sensitivity Troponin Pathway On Patient Flow In An Urban Emergency Department, Edward Hyun Suh, Aleksandr M Tichter, Lauren S Ranard, Andrew Amaranto, Betty C Chang, Phong Anh Huynh, Alexander Kratz, Rebekah Jihae Lee, Leroy E Rabbani, Dana Sacco, Andrew J Einstein

Faculty, Staff and Students Publications

STUDY OBJECTIVE: To evaluate whether the introduction of a 1-hour high-sensitivity cardiac troponin-T (hs-TnT) pathway for patients who present to the emergency department (ED) with suspected acute coronary syndrome (ACS) improves ED patient flow without changing the rate of "missed" major adverse cardiac events (MACE), compared to use of conventional cardiac troponin with an associated 3-hour pathway.

METHODS: This was a prospective, uncontrolled observational study conducted before and after implementation of a 1-hour hs-TnT pathway at a high-volume urban ED. Patients undergoing evaluation for ACS in the ED were enrolled during their initial visit and clinical outcomes were assessed at …

Parental Mosaicism For Apparent De Novo Genetic Variants: Scope, Detection, And Counseling Challenges, Roni Zemet, Ignatia B Van Den Veyver, Paweł Stankiewicz

Duncan NRI Faculty and Staff Publications

The disease burden of de novo mutations (DNMs) has been evidenced only recently when the common application of next-generation sequencing technologies enabled their reliable and affordable detection through family-based clinical exome or genome sequencing. Implementation of exome sequencing into prenatal diagnostics revealed that up to 63% of pathogenic or likely pathogenic variants associated with fetal structural anomalies are apparently de novo, primarily for autosomal dominant disorders. Apparent DNMs have been considered to primarily occur as germline or zygotic events, with consequently negligible recurrence risks. However, there is now evidence that a considerable proportion of them are in fact inherited from …

Differential Effects Of Dietary Macronutrients On The Development Of Oncogenic Kras-Mediated Pancreatic Ductal Adenocarcinoma, Liang Zhu, Juntao Ji, Jianjia Ma, Dan Wang, Muyun Liu, James Xianxing Du, Rong Chen, Wei Hou, James L Abbruzzese, Craig D Logsdon, Vincent W Yang, Yongde Luo, Weiqin Lu

Faculty, Staff and Student Publications

KRAS mutations are prevalent in patients with pancreatic ductal adenocarcinoma (PDAC) and are critical to fostering tumor growth in part by aberrantly rewiring glucose, amino acid, and lipid metabolism. Obesity is a modifiable risk factor for pancreatic cancer. Corroborating this epidemiological observation, mice harboring mutant KRAS are highly vulnerable to obesogenic high-fat diet (HFD) challenges leading to the development of PDAC with high penetrance. However, the contributions of other macronutrient diets, such as diets rich in carbohydrates that are regarded as a more direct source to fuel glycolysis for cancer cell survival and proliferation than HFD, to pancreatic tumorigenesis remain …

Cardiovascular Outcomes In Aortopathy: Gentac Registry Of Genetically Triggered Aortic Aneurysms And Related Conditions, Kathryn W Holmes, Sheila Markwardt, Kim A Eagle, Richard B Devereux, Jonathan W Weinsaft, Federico M Asch, Scott A Lemaire, Cheryl L Maslen, Howard K Song, Dianna M Milewicz, Siddharth K Prakash, Dongchuan Guo, Shaine A Morris, Reed E Pyeritz, Rita C Milewski, William J Ravekes, H C Dietz, Ralph V Shohet, Michael Silberbach, Mary J Roman

Faculty, Staff and Student Publications

BACKGROUND: The GenTAC (Genetically Triggered Thoracic Aortic Aneurysm and Cardiovascular Conditions) Registry enrolled patients with genetic aortopathies between 2007 and 2016.

OBJECTIVES: The purpose of this study was to compare age distribution and probability of elective surgery for proximal aortic aneurysm, any dissection surgery, and cardiovascular mortality among aortopathy etiologies.

METHODS: The GenTAC study had a retrospective/prospective design. Participants with bicuspid aortic valve (BAV) with aneurysm (n = 879), Marfan syndrome (MFS) (n = 861), nonsyndromic heritable thoracic aortic disease (nsHTAD) (n = 378), Turner syndrome (TS) (n = 298), vascular Ehlers-Danlos syndrome (vEDS) (n = 149), and Loeys-Dietz syndrome …

Discovery Of Potent Bet Bromodomain 1 Stereoselective Inhibitors Using Dna-Encoded Chemical Library Selections, Ram K Modukuri, Zhifeng Yu, Zhi Tan, Hai Minh Ta, Melek Nihan Ucisik, Zhuang Jin, Justin L Anglin, Kiran L Sharma, Pranavanand Nyshadham, Feng Li, Kevin Riehle, John C Faver, Kevin Duong, Sureshbabu Nagarajan, Nicholas Simmons, Stephen S Palmer, Mingxing Teng, Damian W Young, Joanna S Yi, Choel Kim, Martin M Matzuk

Duncan NRI Faculty and Staff Publications

BRDT, BRD2, BRD3, and BRD4 comprise the bromodomain and extraterminal (BET) subfamily which contain two similar tandem bromodomains (BD1 and BD2). Selective BD1 inhibition phenocopies effects of tandem BET BD inhibition both in cancer models and, as we and others have reported of BRDT, in the testes. To find novel BET BD1 binders, we screened >4.5 billion molecules from our DNA-encoded chemical libraries with BRDT-BD1 or BRDT-BD2 proteins in parallel. A compound series enriched only by BRDT-BD1 was resynthesized off-DNA, uncovering a potent chiral compound, CDD-724, with >2,000-fold selectivity for inhibiting BRDT-BD1 over BRDT-BD2. CDD-724 stereoisomers exhibited remarkable differences in …

Constitutive Loss Of Dnmt3a Causes Morbid Obesity Through Misregulation Of Adipogenesis, Ayala Tovy, Jaime M Reyes, Linda Zhang, Yung-Hsin Huang, Carina Rosas, Alexes C Daquinag, Anna Guzman, Raghav Ramabadran, Chun-Wei Chen, Tianpeng Gu, Sinjini Gupta, Laura Ortinau, Dongsu Park, Aaron R Cox, Rachel E Rau, Sean M Hartig, Mikhail G Kolonin, Margaret A Goodell

Faculty, Staff and Students Publications

DNA Methyltransferase 3 A (DNMT3A) is an important facilitator of differentiation of both embryonic and hematopoietic stem cells. Heterozygous germline mutations in DNMT3A lead to Tatton-Brown-Rahman Syndrome (TBRS), characterized by obesity and excessive height. While DNMT3A is known to impact feeding behavior via the hypothalamus, here we investigated a role in adipocyte progenitors utilizing heterozygous knockout mice that recapitulate cardinal TBRS phenotypes. These mice become morbidly obese due to adipocyte enlargement and tissue expansion. Adipose tissue in these mice exhibited defects in preadipocyte maturation and precocious activation of inflammatory gene networks, including interleukin-6 signaling. Adipocyte progenitor cell lines lacking DNMT3A …

Poloxamer 407 Induces Hypertriglyceridemia But Decreases Atherosclerosis In Ldlr -/- Mice, Xueying Peng, Zeqin Lian, Xiao-Yuan Dai Perrard, Yunjie Xiao, Jing Ni, Veronica O'Brien, Henry Dong, Henry J Pownall, Christie M Ballantyne, Huaizhu Wu

Faculty, Staff and Students Publications

Background: Hypertriglyceridemia (HTG) increases the risk for atherosclerotic cardiovascular disease, but underlying mechanisms are incompletely understood. Circulating monocytes play an important role in atherogenesis by infiltrating arterial walls, where they differentiate into macrophages. We tested the hypothesis that HTG is mechanistically linked to atherogenesis by altering the monocyte phenotype and infiltration into atherosclerotic lesions in a model of diet-induced atherogenesis in Ldlr−/− mice. Methods: HTG was induced in male Ldlr−/− mice, fed a Western, high-fat high-cholesterol diet, by daily injection of poloxamer 407 (P407), a lipoprotein lipase inhibitor, for seven weeks. Atherosclerosis, monocyte phenotypes, and monocyte migration into atherosclerotic lesions …

Detoxification Role Of Metabolic Glutathione S-Transferase (Gst) Genes In Blood Lead Concentrations Of Jamaican Children With And Without Autism Spectrum Disorder, Mohammad H Rahbar, Maureen Samms-Vaughan, Sori Kim, Sepideh Saroukhani, Jan Bressler, Manouchehr Hessabi, Megan L Grove, Sydonnie Shakspeare-Pellington, Katherine A Loveland

Faculty, Staff and Student Publications

Glutathione S-transferases (GST) are involved in the detoxification of exogenous chemicals including lead (Pb). Using data from 344 pairs of autism spectrum disorder (ASD) cases and age- and sex-matched typically developing (TD) controls (2−8 years old) from Jamaica, we investigated the interaction between three GST genes and ASD status as determinants of blood Pb concentrations (BPbCs). We found that ASD cases had lower geometric mean BPbCs than TD children (1.74 vs. 2.27 µg/dL, p < 0.01). Using a co-dominant genetic model, ASD cases with the Ile/Val genotype for the GSTP1 Ile105Val polymorphism had lower GM BPbCs than TD controls, after adjusting for a known interaction between GSTP1 and GSTT1, child’s parish, socioeconomic status, consumption of lettuce, fried plantains, and canned fish (Ile/Val: 1.78 vs. 2.13 µg/dL, p = 0.03). Similarly, among carriers of the I/I or I/D (I*) genotype for GSTT1 and GSTM1, ASD cases had lower adjusted GM BPbCs than TD controls (GSTT1 I*: 1.61 vs. 1.91 µg/dL, p = 0.01; GSTM1 I*: 1.71 vs. 2.04 µg/dL, p = 0.01). Our findings suggest that genetic polymorphisms in GST genes may influence detoxification of Pb by the enzymes they encode in Jamaican children with and without ASD.

Tumor Immunology And Immunotherapy Of Non-Small-Cell Lung Cancer, Tina Cascone, Jared Fradette, Monika Pradhan, Don L Gibbons

Faculty, Staff and Student Publications

Historically, non-small-cell lung cancer (NSCLC) has been regarded as a nonimmunogenic tumor; however, recent studies have shown that NSCLCs are among the most responsive cancers to monoclonal antibody immune checkpoint inhibitors (ICIs). ICIs have dramatically improved clinical outcomes for a subset of patients (∼20%) with locally advanced and metastatic NSCLC, and they have also demonstrated promise as neoadjuvant therapy for early-stage resectable disease. Nevertheless, the majority of patients with NSCLC are refractory to ICIs for reasons that are poorly understood. Thus, major questions are: how do we initially identify the patients most likely to derive significant clinical benefit from these …

Resistant Maltodextrin Consumption In A Double-Blind, Randomized, Crossover Clinical Trial Induces Specific Changes In Potentially Beneficial Gut Bacteria, Volker Mai, Alyssa M Burns, Rebecca J Solch, Jennifer C Dennis-Wall, Maria Ukhanova, Bobbi Langkamp-Henken

Faculty, Staff and Student Publications

Background: We have previously reported that the addition of resistant maltodextrin (RMD), a fermentable functional fiber, to the diet increases fecal weight as well as the amount of fecal bifidobacteria. Here, we report on the targeted analysis of changes in potentially beneficial gut bacteria associated with the intervention. Objective: The primary objective of this study was to determine the effect of adding 0, 15 and 25 g RMD to the diets of healthy free-living adults on potentially beneficial gut bacteria. Methods: We expanded on our previously reported microbiota analysis in a double-blind, placebo-controlled feeding study (NCT02733263) by performing additional qPCR …

A Concise Synthetic Method For Constructing 3-Substituted Piperazine-2-Acetic Acid Esters From 1,2-Diamines, Srinivas Chamakuri, Sunny Ann Tang, Kevin A Tran, Shiva Krishna Reddy Guduru, Peter K Bolin, Kevin R Mackenzie, Damian W Young

Faculty, Staff and Students Publications

We report a short synthetic route for synthesizing 2,3-substituted piperazine acetic acid esters. Optically pure amino acids were efficiently converted into 1,2-diamines that could be utilized to deliver the title 2,3-substituted piperazines in five steps with a high enantiomeric purity. The novel route facilitated, for the first time, the synthesis of 3-phenyl substituted-2-piperazine acetic acid esters that were difficult to achieve using other methods; however, in this case, the products underwent racemization.

Maf1, A Repressor Of Rna Polymerase Iii-Dependent Transcription, Regulates Bone Mass, Ellen Phillips, Naseer Ahmad, Li Sun, James Iben, Christopher J Walkey, Aleksandra Rusin, Tony Yuen, Clifford J Rosen, Ian M Willis, Mone Zaidi, Deborah L Johnson

Faculty, Staff and Students Publications

MAF1, a key repressor of RNA polymerase (pol) III-mediated transcription, has been shown to promote mesoderm formation in vitro. Here, we show that MAF1 plays a critical role in regulating osteoblast differentiation and bone mass. Global deletion of MAF1 (Maf1-/- mice) produced a high bone mass phenotype. However, osteoblasts isolated from Maf1-/- mice showed reduced osteoblastogenesis ex vivo. Therefore, we determined the phenotype of mice overexpressing MAF1 in cells from the mesenchymal lineage (Prx1-Cre;LSL-MAF1 mice). These mice showed increased bone mass. Ex vivo, cells from these mice showed enhanced osteoblastogenesis concordant with their high …

Association Study Between Mucin 4 (Muc4) Polymorphisms And Idiopathic Recurrent Pregnancy Loss In A Korean Population, Ji-Hyang Kim, Han-Sung Park, Jeong-Yong Lee, Eun-Ju Ko, Young-Ran Kim, Hee-Young Cho, Woo-Sik Lee, Eun-Hee Ahn, Nam-Keun Kim

Faculty, Staff and Student Publications

Recurrent pregnancy loss (RPL) is the loss of two or more consecutive pregnancies before 20 weeks of gestational age. Our study investigated whether mucin 4 (MUC4) polymorphisms are associated with RPL. MUC polymorphisms (rs882605 C>A, rs1104760 A>G, rs2688513 A>G, rs2258447 C>T, and rs2291652 A>G) were genotyped in 374 women with RPL and 239 controls of Korean ethnicity using polymerase chain reaction-restriction fragment length polymorphism analysis and the TaqMan probe SNP genotyping assay. Differences in genotype frequencies between cases of RPL and the controls were compared. MUC4 rs882605 C>A and rs1104760 A>G polymorphisms were …

A Nickase Cas9 Gene-Drive System Promotes Super-Mendelian Inheritance In Drosophila, Víctor López Del Amo, Sara Sanz Juste, Valentino M Gantz

Faculty, Staff and Student Publications

CRISPR-based gene-drives have been proposed for managing insect populations, including disease-transmitting mosquitoes, due to their ability to bias their inheritance toward super-Mendelian rates (>50%). Current technologies use a Cas9 that introduces DNA double-strand breaks into the opposing wild-type allele to replace it with a copy of the gene-drive allele via DNA homology-directed repair. However, the use of different Cas9 versions is unexplored, and alternative approaches could increase the available toolkit for gene-drive designs. Here, we report a gene-drive that relies on Cas9 nickases that generate staggered paired nicks in DNA to propagate the engineered gene-drive cassette. We show that …

Impact Of Estrogen Receptor Expression On Prognosis Of Ovarian Cancer According To Antibody Clone Used For Immunohistochemistry: A Meta-Analysis, Chun Wai Ng, Kwong-Kwok Wong

Faculty, Staff and Student Publications

Background: The prognostic value of the expression of estrogen receptor (ER) subtypes ER⍺ and ERβ in ovarian cancer has previously been evaluated by meta-analyses. However, the results are contradictory and controversial.

Methods: We conducted an updated meta-analysis with stringent inclusion criteria to ensure homogeneous studies to determine the effect of ER subtypes on ovarian cancer prognosis. Articles were retrieved by systematic search of PubMed and Web of Science for articles dated up to June 2021. Only studies with known hazard ratio (HR) and antibody clone for immunochemistry (IHC) were included. Pooled HRs with the corresponding 95% confidence intervals (CIs) were …

Characteristics And Outcomes Of Patients With Blastic Plasmacytoid Dendritic Cell Neoplasm Treated With Frontline Hcvad, Naveen Pemmaraju, Nathaniel R Wilson, Guillermo Garcia-Manero, Koji Sasaki, Joseph D Khoury, Nitin Jain, Gautam Borthakur, Farhad Ravandi, Naval Daver, Tapan Kadia, Courtney Dinardo, Elias Jabbour, Sherry Pierce, Muzaffar Qazilbash, Marina Konopleva, Hagop Kantarjian

Faculty, Staff and Student Publications

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a clinically aggressive blood cancer, often involving the skin, bone marrow, lymph nodes, and central nervous system (CNS) in 20% to 30% of patients. Despite significant progress in CD123- and BCL-2-targeted therapy, most patients are not cured without hematopoietic stem cell transplant (HSCT), and CNS relapses occur quite frequently. Combination approaches with targeted and chemotherapy agents plus incorporation of prophylactic CNS-directed therapy are urgently needed. In this setting, we sought to analyze outcomes using the cytotoxic chemotherapy backbone regimen hyperfractionated cyclophosphamide, vincristine, adriamycin, and dexamethasone (HCVAD). We conducted a retrospective analysis of patients …

Targeting Aberrant Replication And Dna Repair Events For Treating Breast Cancers, Subapriya Rajamanickam, Jun Hyoung Park, Panneerdoss Subbarayalu, Santosh Timilsina, Kaitlyn Bates, Pooja Yadav, Saif S R Nirzhor, Vijay Eedunuri, Tabrez A Mohammad, Kwang Hwa Jung, Benjamin Onyeagucha, Nourhan Abdelfattah, Raymond Benevides, Grace Lee, Yidong Chen, Ratna Vadlamudi, Andrew Brenner, Virginia Kaklamani, Ismail Jatoi, John Kuhn, Robert Hromas, Yogesh K Gupta, Benny A Kaipparettu, Jack L Arbiser, Manjeet K Rao

Faculty, Staff and Students Publications

The major limitations of DNA-targeting chemotherapy drugs include life-threatening toxicity, acquired resistance and occurrence of secondary cancers. Here, we report a small molecule, Carbazole Blue (CB), that binds to DNA and inhibits cancer growth and metastasis by targeting DNA-related processes that tumor cells use but not the normal cells. We show that CB inhibits the expression of pro-tumorigenic genes that promote unchecked replication and aberrant DNA repair that cancer cells get addicted to survive. In contrast to chemotherapy drugs, systemic delivery of CB suppressed breast cancer growth and metastasis with no toxicity in pre-clinical mouse models. Using PDX and ex …

Tissue-Specific Variations In Transcription Factors Elucidate Complex Immune System Regulation, Hengwei Lu, Yi-Ching Tang, Assaf Gottlieb

Faculty, Staff and Student Publications

Gene expression plays a key role in health and disease. Estimating the genetic components underlying gene expression can thus help understand disease etiology. Polygenic models termed "transcriptome imputation" are used to estimate the genetic component of gene expression, but these models typically consider only the cis regions of the gene. However, these cis-based models miss large variability in expression for multiple genes. Transcription factors (TFs) that regulate gene expression are natural candidates for looking for additional sources of the missing variability. We developed a hypothesis-driven approach to identify second-tier regulation by variability in TFs. Our approach tested two models …

Dedifferentiation-Mediated Stem Cell Niche Maintenance In Early-Stage Ductal Carcinoma In Situ Progression: Insights From A Multiscale Modeling Study, Joseph D Butner, Prashant Dogra, Caroline Chung, Javier Ruiz-Ramírez, Sara Nizzero, Marija Plodinec, Xiaoxian Li, Ping-Ying Pan, Shu-Hsia Chen, Vittorio Cristini, Bulent Ozpolat, George A Calin, Zhihui Wang

Faculty, Staff and Student Publications

We present a multiscale agent-based model of ductal carcinoma in situ (DCIS) to study how key phenotypic and signaling pathways are involved in the early stages of disease progression. The model includes a phenotypic hierarchy, and key endocrine and paracrine signaling pathways, and simulates cancer ductal growth in a 3D lattice-free domain. In particular, by considering stochastic cell dedifferentiation plasticity, the model allows for study of how dedifferentiation to a more stem-like phenotype plays key roles in the maintenance of cancer stem cell populations and disease progression. Through extensive parameter perturbation studies, we have quantified and ranked how DCIS is …

Mutational Activation Of The Nrf2 Pathway Upregulates Kynureninase Resulting In Tumor Immunosuppression And Poor Outcome In Lung Adenocarcinoma, Johannes F Fahrmann, Ichidai Tanaka, Ehsan Irajizad, Xiangying Mao, Jennifer B Dennison, Eunice Murage, Julian Casabar, Jeffrey Mayo, Qian Peng, Muge Celiktas, Jody V Vykoukal, Soyoung Park, Ayumu Taguchi, Oliver Delgado, Satyendra C Tripathi, Hiroyuki Katayama, Luisa Maren Solis Soto, Jaime Rodriguez-Canales, Carmen Behrens, Ignacio Wistuba, Samir Hanash, Edwin J Ostrin

Faculty, Staff and Student Publications

Activation of the NRF2 pathway through gain-of-function mutations or loss-of-function of its suppressor KEAP1 is a frequent finding in lung cancer. NRF2 activation has been reported to alter the tumor microenvironment. Here, we demonstrated that NRF2 alters tryptophan metabolism through the kynurenine pathway that is associated with a tumor-promoting, immune suppressed microenvironment. Specifically, proteomic profiles of 47 lung adenocarcinoma (LUAD) cell lines (11 KEAP1 mutant and 36 KEAP1 wild-type) revealed the tryptophan-kynurenine enzyme kynureninase (KYNU) as a top overexpressed protein associated with activated NRF2. The siRNA-mediated knockdown of NFE2L2, the gene encoding for NRF2, or activation of the NRF2 …

Impaired Gate16-Mediated Exocytosis In Exocrine Tissues Causes Sjögren’S Syndrome-Like Exocrinopathy, Akiko Suzuki, Chihiro Iwaya, Kenichi Ogata, Hiroki Yoshioka, Junbo Shim, Isei Tanida, Masaaki Komatsu, Norihiro Tada, Junichi Iwata

Faculty, Staff and Student Publications

Sjögren's syndrome (SjS) is a chronic autoimmune disease characterized by immune cell infiltration of the exocrine glands, mainly the salivary and lacrimal glands. Despite recent advances in the clinical and mechanistic characterization of the disease, its etiology remains largely unknown. Here, we report that mice with a deficiency for either Atg7 or Atg3, which are enzymes involved in the ubiquitin modification pathway, in the salivary glands exhibit a SjS-like phenotype, characterized by immune cell infiltration with autoantibody detection, acinar cell death, and dry mouth. Prior to the onset of the SjS-like phenotype in these null mice, we detected an accumulation …

Definition Of Germ Layer Cell Lineage Alternative Splicing Programs Reveals A Critical Role For Quaking In Specifying Cardiac Cell Fate, W Samuel Fagg, Naiyou Liu, Ulrich Braunschweig, Karen Larissa Pereira De Castro, Xiaoting Chen, Frederick S Ditmars, Steven G Widen, John Paul Donohue, Katalin Modis, William K Russell, Jeffrey H Fair, Matthew T Weirauch, Benjamin J Blencowe, Mariano A Garcia-Blanco

Faculty, Staff and Student Publications

Alternative splicing is critical for development; however, its role in the specification of the three embryonic germ layers is poorly understood. By performing RNA-Seq on human embryonic stem cells (hESCs) and derived definitive endoderm, cardiac mesoderm, and ectoderm cell lineages, we detect distinct alternative splicing programs associated with each lineage. The most prominent splicing program differences are observed between definitive endoderm and cardiac mesoderm. Integrative multi-omics analyses link each program with lineage-enriched RNA binding protein regulators, and further suggest a widespread role for Quaking (QKI) in the specification of cardiac mesoderm. Remarkably, knockout of QKI disrupts the cardiac mesoderm-associated alternative …

Tite-Boin12: A Bayesian Phase I/Ii Trial Design To Find The Optimal Biological Dose With Late-Onset Toxicity And Efficacy, Yanhong Zhou, Ruitao Lin, J Jack Lee, Daniel Li, Li Wang, Ruobing Li, Ying Yuan

Faculty, Staff and Student Publications

In the era of immunotherapies and targeted therapies, the focus of early phase clinical trials has shifted from finding the maximum tolerated dose to identifying the optimal biological dose (OBD), which maximizes the toxicity-efficacy trade-off. One major impediment to using adaptive designs to find OBD is that efficacy or/and toxicity are often late-onset, hampering the designs’ real-time decision rules for treating new patients. To address this issue, we propose the model-assisted TITE-BOIN12 design to find OBD with late-onset toxicity and efficacy. As an extension of the BOIN12 design, the TITE-BOIN12 design also uses utility to quantify the toxicity-efficacy trade-off. We …