Pathology Commons^™

Increase In Hnrnpa1 Expression Suffices To Kill Motor Neurons In Transgenic Rats, Xionghao Liu, Tingting Zhang, Qinxue Wu, Cao Huang, Xu-Gang Xia, Hongxia Zhou, Bo Huang

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

A dominant mutation in hnRNPA1 causes amyotrophic lateral sclerosis (ALS), but it is not known whether this mutation leads to motor neuron death through increased or decreased function. To elucidate the relationship between pathogenic hnRNPA1 mutation and its native function, we created novel transgenic rats that overexpressed wildtype rat hnRNPA1 exclusively in motor neurons. This targeted expression of wildtype hnRNPA1 caused severe motor neuron loss and subsequent denervation muscle atrophy in transgenic rats that recapitulated the characteristics of ALS. These findings demonstrate that the augmentation of hnRNPA1 expression suffices to trigger motor neuron degeneration and the manifestation of ALS-like phenotypes. …

Potassium Channel Subfamily T Member 1(Kcnt1) Pathological Variant Causing Epilepsy Of Infancy With Migrating Focal Seizures: A Case Report, Prem Chand, Meher Angez, Ayesha Nasir Hameed, Salman Kirmani

Department of Paediatrics and Child Health

Pathological mutation of potassium channel subfamily T member 1 (KCNT1) gene causes an autosomal dominant disorder characterised by secondarily generalised seizures/migratory focal seizure, cyanosis, and dysmorphic features. We report the case of a five-month old male with pathological KCNT1 variant who presented with focal clonic seizures, Mongol spots, and grade two systolic murmur at the left lower sternal border and loud P2. The seizures were refractory to most anti-epileptic drugs but showed some response to Valproic acid. This case demonstrated that EIMFS is a grave infantile epileptic encephalopathy which is refractory to anti epileptic drugs and can present with a …

Clinical Laboratory Testing Practices In Diffuse Gliomas Prior To Publication Of 2021 World Health Organization Classification Of Central Nervous System Tumors, Shakti H. Ramkissoon, Helen Fernandes, Dolores H. Lopez-Terrada, Meera R. Hameed, Dimitri G. Trembath, Julia A. Bridge, Neal I. Lindeman, Rhona J. Souers, Patricia Vasalos, Daniel J Brat, Joel T. Moncur

Journal Articles: Pathology and Microbiology

CONTEXT.—: Integration of molecular data into glioma classification supports diagnostic, prognostic, and therapeutic decision-making; however, testing practices for these informative biomarkers in clinical laboratories remain unclear.

OBJECTIVE.—: To examine the prevalence of molecular testing for clinically relevant biomarkers in adult and pediatric gliomas through review of a College of American Pathologists proficiency testing survey prior to the release of the 2021 World Health Organization Classification of Central Nervous System Tumors.

DESIGN.—: College of American Pathologists proficiency testing 2020 survey results from 96 laboratories performing molecular testing for diffuse gliomas were used to determine the use of testing for molecular biomarkers …

Dach1 Mutation Frequency In Endometrial Cancer Is Associated With High Tumor Mutation Burden, Mckayla J. Riggs, Nan Lin, Chi Wang, Dava W. Piecoro, Rachel W. Miller, Oliver A. Hampton, Mahadev Rao, Frederick R. Ueland, Jill M. Kolesar

Obstetrics and Gynecology Faculty Publications

OBJECTIVE: DACH1 is a transcriptional repressor and tumor suppressor gene frequently mutated in melanoma, bladder, and prostate cancer. Loss of DACH1 expression is associated with poor prognostic features and reduced overall survival in uterine cancer. In this study, we utilized the Oncology Research Information Exchange Network (ORIEN) Avatar database to determine the frequency of DACH1 mutations in patients with endometrial cancer in our Kentucky population.

METHODS: We obtained clinical and genomic data for 65 patients with endometrial cancer from the Markey Cancer Center (MCC). We examined the clinical attributes of the cancers by DACH1 status by comparing whole-exome sequencing (WES), …

Genomic Characterization Of Malignant Progression In Neoplastic Pancreatic Cysts, Michaël Noë, Noushin Niknafs, Catherine G Fischer, Wenzel M Hackeng, Violeta Beleva Guthrie, Waki Hosoda, Marija Debeljak, Eniko Papp, Vilmos Adleff, James R White, Claudio Luchini, Antonio Pea, Aldo Scarpa, Giovanni Butturini, Giuseppe Zamboni, Paola Castelli, Seung-Mo Hong, Shinichi Yachida, Nobuyoshi Hiraoka, Anthony J Gill, Jaswinder S Samra, G Johan A Offerhaus, Anne Hoorens, Joanne Verheij, Casper Jansen, N Volkan Adsay, Wei Jiang, Jordan Winter, Jorge Albores-Saavedra, Benoit Terris, Elizabeth D Thompson, Nicholas J Roberts, Ralph H Hruban, Rachel Karchin, Robert B Scharpf, Lodewijk A A Brosens, Victor E Velculescu, Laura D Wood

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Intraductal papillary mucinous neoplasms (IPMNs) and mucinous cystic neoplasms (MCNs) are non-invasive neoplasms that are often observed in association with invasive pancreatic cancers, but their origins and evolutionary relationships are poorly understood. In this study, we analyze 148 samples from IPMNs, MCNs, and small associated invasive carcinomas from 18 patients using whole exome or targeted sequencing. Using evolutionary analyses, we establish that both IPMNs and MCNs are direct precursors to pancreatic cancer. Mutations in SMAD4 and TGFBR2 are frequently restricted to invasive carcinoma, while RNF43 alterations are largely in non-invasive lesions. Genomic analyses suggest an average window of over three …

Tumor Heterogeneity As A Predictor Of Response To Neoadjuvant Chemotherapy In Locally Advanced Rectal Cancer, Alissa Greenbaum, David R. Martin, Therese J. Bocklage, Ji-Hyun Lee, Scott A. Ness, Ashwani Rajput

Pathology and Laboratory Medicine Faculty Publications

BACKGROUND: Neoadjuvant chemoradiotherapy (nCRT) is the standard of care for locally advanced adenocarcinoma of the rectum, but it is currently unknown which patients have disease that will respond. This study tested the correlation between response to nCRT and intratumoral heterogeneity using next-generation sequencing assays.

PATIENTS AND METHODS: DNA was extracted from formalin-fixed, paraffin-embedded biopsy samples from a cohort of patients with locally advanced rectal adenocarcinoma (T3/4 or N1/2 disease) who received nCRT. High read-depth sequencing of > 400 cancer-relevant genes was performed. Tumor mutations and variant allele frequencies were used to calculate mutant-allele tumor heterogeneity (MATH) scores as measures of intratumoral …

Mutational Landscape Of Head And Neck Squamous Cell Carcinomas In A South Asian Population, Kulsoom Ghias, Sadiq S. Rehmani, Safina Abdul Razzak, Sarosh Madani, M Kamran Azim, Rashida Ahmed, Mumtaz J Khan

Department of Biological & Biomedical Sciences

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer type globally and contributes significantly to burden of disease in South Asia. In Pakistan, HNSCC is anmong the most commonly diagnosed cancer in males and females. The increasing regional burden of HNSCC along with a unique set of risk factors merited a deeper investigation of the disease at the genomic level. Whole exome sequencing of HNSCC samples and matched normal genomic DNA (n=7) was performed. Significant somatic single nucleotide variants (SNVs) were identified and pathway analysis performed to determine frequently affected signaling pathways. We identified significant, novel …

Intracellular Ca 2+ Sensing: Role In Calcium Homeostasis And Signaling, Rafaela Bagur, György Hajnóczky

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Ca²⁺ is a ubiquitous intracellular messenger that controls diverse cellular functions but can become toxic and cause cell death. Selective control of specific targets depends on spatiotemporal patterning of the calcium signal and decoding it by multiple, tunable, and often strategically positioned Ca²⁺-sensing elements. Ca²⁺ is detected by specialized motifs on proteins that have been biochemically characterized decades ago. However, the field of Ca²⁺ sensing has been reenergized by recent progress in fluorescent technology, genetics, and cryo-EM. These approaches exposed local Ca²⁺-sensing mechanisms inside organelles and at the organellar interfaces, revealed how Ca …

Zinc Transporters Ybtx And Znuabc Are Required For The Virulence Of Yersinia Pestis In Bubonic And Pneumonic Plague In Mice, Alexander G. Bobrov, Olga Kirillina, Marina Y. Fosso, Jacqueline D. Fetherston, M. Clarke Miller, Tiva T. Vancleave, Joseph A. Burlison, William K. Arnold, Matthew B. Lawrenz, Sylvie Garneau-Tsodikova, Robert D. Perry

Microbiology, Immunology, and Molecular Genetics Faculty Publications

A number of bacterial pathogens require the ZnuABC Zinc (Zn²⁺) transporter and/or a second Zn²⁺ transport system to overcome Zn²⁺ sequestration by mammalian hosts. Previously we have shown that in addition to ZnuABC, Yersinia pestis possesses a second Zn²⁺ transporter that involves components of the yersiniabactin (Ybt), siderophore-dependent iron transport system. Synthesis of the Ybt siderophore and YbtX, a member of the major facilitator superfamily, are both critical components of the second Zn²⁺ transport system. Here we demonstrate that a ybtX znu double mutant is essentially avirulent in mouse models of bubonic and pneumonic …

Neuropathological And Genetic Correlates Of Survival And Dementia Onset In Synucleinopathies: A Retrospective Analysis, David J. Irwin, Murray Grossman, Daniel Weintraub, Howard I. Hurtig, John E. Duda, Sharon X. Xie, Edward B. Lee, Vivianna M. Van Deerlin, Oscar L. Lopez, Julia K. Kofler, Peter T. Nelson, Gregory A. Jicha, Randy Woltjer, Joseph F. Quinn, Jeffery Kaye, James B. Leverenz, Debby Tsuang, Katelan Longfellow, Dora Yearout, Walter Kukull, C. Dirk Keene, Thomas J. Montine, Cyrus P. Zabetian, John Q. Trojanowski

Sanders-Brown Center on Aging Faculty Publications

Background

Great heterogeneity exists in survival and the interval between onset of motor symptoms and dementia symptoms across synucleinopathies. We aimed to identify genetic and pathological markers that have the strongest association with these features of clinical heterogeneity in synucleinopathies.

Methods

In this retrospective study, we examined symptom onset, and genetic and neuropathological data from a cohort of patients with Lewy body disorders with autopsy-confirmed α synucleinopathy (as of Oct 1, 2015) who were previously included in other studies from five academic institutions in five cities in the USA. We used histopathology techniques and markers to assess the burden of …

Biallelic Mutations In Tbcd, Encoding The Tubulin Folding Cofactor D, Perturb Microtubule Dynamics And Cause Early-Onset Encephalopathy., Elisabetta Flex, Marcello Niceta, Serena Cecchetti, Isabelle Thiffault, Margaret G. Au, Alessandro Capuano, Emanuela Piermarini, Anna A. Ivanova, Joshua W. Francis, Giovanni Chillemi, Balasubramanian Chandramouli, Giovanna Carpentieri, Charlotte A. Haaxma, Andrea Ciolfi, Simone Pizzi, Ganka V. Douglas, Kara Levine, Antonella Sferra, Maria Lisa Dentici, Rolph R. Pfundt, Jean-Baptist Lepichon, Emily G. Farrow, Frank Baas, Fiorella Piemonte, Bruno Dallapiccola, John M. Graham, Carol J. Saunders, Enrico Bertini, Richard A. Kahn, David A. Koolen, Marco Tartaglia

Manuscripts, Articles, Book Chapters and Other Papers

Microtubules are dynamic cytoskeletal elements coordinating and supporting a variety of neuronal processes, including cell division, migration, polarity, intracellular trafficking, and signal transduction. Mutations in genes encoding tubulins and microtubule-associated proteins are known to cause neurodevelopmental and neurodegenerative disorders. Growing evidence suggests that altered microtubule dynamics may also underlie or contribute to neurodevelopmental disorders and neurodegeneration. We report that biallelic mutations in TBCD, encoding one of the five co-chaperones required for assembly and disassembly of the αβ-tubulin heterodimer, the structural unit of microtubules, cause a disease with neurodevelopmental and neurodegenerative features characterized by early-onset cortical atrophy, secondary hypomyelination, microcephaly, thin …

Staphylococcus Aureus Biofilms Induce Macrophage Dysfunction Through Leukocidin Ab And Alpha-Toxin., Tyler D. Scherr, Mark L. Hanke, Ouwen Huang, David B.A. James, Alexander R. Horswill, Kenneth W. Bayles, Paul D. Fey, Victor J. Torres, Tammy Kielian

Journal Articles: Pathology and Microbiology

UNLABELLED: The macrophage response to planktonic Staphylococcus aureus involves the induction of proinflammatory microbicidal activity. However, S. aureus biofilms can interfere with these responses in part by polarizing macrophages toward an anti-inflammatory profibrotic phenotype. Here we demonstrate that conditioned medium from mature S. aureus biofilms inhibited macrophage phagocytosis and induced cytotoxicity, suggesting the involvement of a secreted factor(s). Iterative testing found the active factor(s) to be proteinaceous and partially agr-dependent. Quantitative mass spectrometry identified alpha-toxin (Hla) and leukocidin AB (LukAB) as critical molecules secreted by S. aureus biofilms that inhibit murine macrophage phagocytosis and promote cytotoxicity. A role for Hla …

Evidence For Aberrant Astrocyte Hemichannel Activity In Juvenile Neuronal Ceroid Lipofuscinosis (Jncl)., Maria Burkovetskaya, Nikolay Karpuk, Juan Xiong, Megan Bosch, Michael D. Boska, Hideyuki Takeuchi, Akio Suzumura, Tammy Kielian

Journal Articles: Pathology and Microbiology

Juvenile Neuronal Ceroid Lipofuscinosis (JNCL) is a lysosomal storage disease caused by an autosomal recessive mutation in CLN3 that leads to vision loss, progressive cognitive and motor decline, and premature death. Morphological evidence of astrocyte activation occurs early in the disease process and coincides with regions where neuronal loss eventually ensues. However, the consequences of CLN3 mutation on astrocyte function remain relatively ill-defined. Astrocytes play a critical role in CNS homeostasis, in part, by their ability to regulate the extracellular milieu via the formation of extensive syncytial networks coupled by gap junction (GJ) channels. In contrast, unopposed hemichannels (HCs) have …

Ccpa Regulates Arginine Biosynthesis In Staphylococcus Aureus Through Repression Of Proline Catabolism., Austin S. Nuxoll, Steven M. Halouska, Marat Sadykov, Mark L. Hanke, Kenneth W. Bayles, Tammy Kielian, Robert Powers, Paul D. Fey

Journal Articles: Pathology and Microbiology

Staphylococcus aureus is a leading cause of community-associated and nosocomial infections. Imperative to the success of S. aureus is the ability to adapt and utilize nutrients that are readily available. Genomic sequencing suggests that S. aureus has the genes required for synthesis of all twenty amino acids. However, in vitro experimentation demonstrates that staphylococci have multiple amino acid auxotrophies, including arginine. Although S. aureus possesses the highly conserved anabolic pathway that synthesizes arginine via glutamate, we demonstrate here that inactivation of ccpA facilitates the synthesis of arginine via the urea cycle utilizing proline as a substrate. Mutations within putA, rocD, …

Contribution Of The Staphylococcus Aureus Atl Am And Gl Murein Hydrolase Activities In Cell Division, Autolysis, And Biofilm Formation., Jeffrey L. Bose, Mckenzie K. Lehman, Paul D. Fey, Kenneth W. Bayles

Journal Articles: Pathology and Microbiology

The most prominent murein hydrolase of Staphylococcus aureus, AtlA, is a bifunctional enzyme that undergoes proteolytic cleavage to yield two catalytically active proteins, an amidase (AM) and a glucosaminidase (GL). Although the bifunctional nature of AtlA has long been recognized, most studies have focused on the combined functions of this protein in cell wall metabolism and biofilm development. In this study, we generated mutant derivatives of the clinical S. aureus isolate, UAMS-1, in which one or both of the AM and GL domains of AtlA have been deleted. Examination of these strains revealed that each mutant exhibited growth rates comparable …

Nuclease Modulates Biofilm Formation In Community-Associated Methicillin-Resistant Staphylococcus Aureus., Megan R. Kiedrowski, Jeffrey S. Kavanaugh, Cheryl L. Malone, Joe M. Mootz, Jovanka M. Voyich, Mark S. Smeltzer, Kenneth W. Bayles, Alexander R. Horswill

Journal Articles: Pathology and Microbiology

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is an emerging contributor to biofilm-related infections. We recently reported that strains lacking sigma factor B (sigB) in the USA300 lineage of CA-MRSA are unable to develop a biofilm. Interestingly, when spent media from a USA300 sigB mutant was incubated with other S. aureus strains, biofilm formation was inhibited. Following fractionation and mass spectrometry analysis, the major anti-biofilm factor identified in the spent media was secreted thermonuclease (Nuc). Considering reports that extracellular DNA (eDNA) is an important component of the biofilm matrix, we investigated the regulation and role of Nuc in USA300. The expression of …

Brca1 Status In Pakistani Breast Cancer Patients With Moderate Family History, Tariq Moatter, Muniba Aban, Shaista Khan, Iqbal Azam, Shahid Pervez

Department of Pathology and Laboratory Medicine

OBJECTIVE: To determine BRCA1 status in breast carcinoma patients of Pakistani origin.

STUDY DESIGN: Observational study.

PLACE AND DURATION OF STUDY: The Oncology Clinics of the Aga Khan University Hospital, Karachi, between May 2005 and December 2009.

METHODOLOGY: Fifty three breast cancer patients based on clinical and laboratory diagnosis were recruited for this study. Moderate family history was defined as having a close relative (mother, daughter, sister) diagnosed with breast cancer under 45 years. Peripheral blood samples were collected from each patient in a 5 ml tube containing EDTA as anticoagulant. Subsequent to DNA extraction, mutational analysis of BRCA1 exons …

Tlr4 Mutation Reduces Microglial Activation, Increases Aβ Deposits And Exacerbates Cognitive Deficits In A Mouse Model Of Alzheimer's Disease, Min Song, Jingji Jin, Jinghong Kou, Abhinandan Pattanayak, Jamaal Rehman, Hong-Duck Kim, Ken-Ichiro Fukuchi

NYMC Faculty Publications

BACKGROUND: Amyloid plaques, a pathological hallmark of Alzheimer's disease (AD), are accompanied by activated microglia. The role of activated microglia in the pathogenesis of AD remains controversial: either clearing Aβ deposits by phagocytosis or releasing proinflammatory cytokines and cytotoxic substances. Microglia can be activated via toll-like receptors (TLRs), a class of pattern-recognition receptors in the innate immune system. We previously demonstrated that an AD mouse model homozygous for a loss-of-function mutation of TLR4 had increases in Aβ deposits and buffer-soluble Aβ in the brain as compared with a TLR4 wild-type AD mouse model at 14-16 months of age. However, it …

Epistatic Relationships Between Sara And Agr In Staphylococcus Aureus Biofilm Formation., Karen E. Beenken, Lara N. Mrak, Linda M. Griffin, Agnieszka K. Zielinska, Lindsey N. Shaw, Kelly C. Rice, Alexander R. Horswill, Kenneth W. Bayles, Mark S. Smeltzer

Journal Articles: Pathology and Microbiology

BACKGROUND: The accessory gene regulator (agr) and staphylococcal accessory regulator (sarA) play opposing roles in Staphylococcus aureus biofilm formation. There is mounting evidence to suggest that these opposing roles are therapeutically relevant in that mutation of agr results in increased biofilm formation and decreased antibiotic susceptibility while mutation of sarA has the opposite effect. To the extent that induction of agr or inhibition of sarA could potentially be used to limit biofilm formation, this makes it important to understand the epistatic relationships between these two loci.

METHODOLOGY/PRINCIPAL FINDINGS: We generated isogenic sarA and agr mutants in clinical isolates of S. …

Modulation Of Edna Release And Degradation Affects Staphylococcus Aureus Biofilm Maturation., Ethan E. Mann, Kelly C. Rice, Blaise R. Boles, Jennifer L. Endres, Dev Ranjit, Lakshmi Chandramohan, Laura H. Tsang, Mark S. Smeltzer, Alexander R. Horswill, Kenneth W. Bayles

Journal Articles: Pathology and Microbiology

Recent studies have demonstrated a role for Staphylococcus aureus cidA-mediated cell lysis and genomic DNA release in biofilm adherence. The current study extends these findings by examining both temporal and additional genetic factors involved in the control of genomic DNA release and degradation during biofilm maturation. Cell lysis and DNA release were found to be critical for biofilm attachment during the initial stages of development and the released DNA (eDNA) remained an important matrix component during biofilm maturation. This study also revealed that an lrgAB mutant exhibits increased biofilm adherence and matrix-associated eDNA consistent with its proposed role as an …