Medicine and Health Sciences Commons^™

Genetic Separation Of Brca1 Functions Reveal Mutation-Dependent Polθ Vulnerabilities, John J. Krais, David J. Glass, Ilse Chudoba, Yifan Wang, Wanjuan Feng, Dennis Simpson, Pooja Patel, Zemin Liu, Ryan Neumann-Domer, Robert G. Betsch, Andrea J. Bernhardy, Alice M. Bradbury, Jason Conger, Wei-Ting Yueh, Joseph Nacson, Richard T. Pomerantz, Gaorav P. Gupta, Joseph R. Testa, Neil Johnson

Department of Biochemistry and Molecular Biology Faculty Papers

Homologous recombination (HR)-deficiency induces a dependency on DNA polymerase theta (Polθ/Polq)-mediated end joining, and Polθ inhibitors (Polθi) are in development for cancer therapy. BRCA1 and BRCA2 deficient cells are thought to be synthetic lethal with Polθ, but whether distinct HR gene mutations give rise to equivalent Polθ-dependence, and the events that drive lethality, are unclear. In this study, we utilized mouse models with separate Brca1 functional defects to mechanistically define Brca1-Polθ synthetic lethality. Surprisingly, homozygous Brca1 mutant, Polq−/− cells were viable, but grew slowly and had chromosomal instability. Brca1 mutant cells proficient in DNA end resection were …

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. …

Phenotype And Genotype Heterogeneity Of Pla2g6-Associated Neurodegeneration In A Cohort Of Pediatric And Adult Patients, Ali Zare Dehnavi, Maryam Bemanalizadeh, Seyyed Mohammad Kahani, Mahmoud Reza Ashrafi, Mohammad Rohani, Mehran Beiraghi Toosi, Morteza Heidari, Sareh Hosseinpour, Behnam Amini, Shaghayegh Zokaei, Zahra Rezaei, Hajar Aryan, Man Amanat, Hassan Vahidnezhad, Pouria Mohammadi, Masoud Garshasbi, Ali Reza Tavasoli

Department of Dermatology and Cutaneous Biology Faculty Papers

BACKGROUND: Phospholipase-associated neurodegeneration (PLAN) caused by mutations in the PLA2G6 gene is a rare neurodegenerative disorder that presents with four sub-groups. Infantile neuroaxonal dystrophy (INAD) and PLA2G6-related dystonia-parkinsonism are the main two subtypes. In this cohort, we reviewed clinical, imaging, and genetic features of 25 adult and pediatric patients harboring variants in the PLA2G6.

METHODS: An extensive review of the patients' data was carried out. Infantile Neuroaxonal Dystrophy Rating Scale (INAD-RS) was used for evaluating the severity and progression of INAD patients. Whole-exome sequencing was used to determine the disease's underlying etiology followed by co-segregation analysis using Sanger sequencing. In …

A Rare Metastatic Mesenteric Malignant Pecoma With Tsc2 Mutation Treated With Palliative Surgical Resection And Nab-Sirolimus: A Case Report, Luke Meredith, Timothy Chao, Avinoam Nevler, Atrayee Basu Mallick, Rajan Singla, Peter Mccue, Wilbur Bowne, Wei Jiang, Md, Phd

Kimmel Cancer Center Faculty Papers

BACKGROUND: Malignant perivascular epithelioid cell tumors (PEComas) are exceedingly rare malignant mesenchymal neoplasms with characteristic morphological and immunohistochemical (IHC) patterns. However, some malignant PEComas are poorly differentiated with atypical histopathological features, making a definitive diagnosis difficult. PEComas are most commonly found in females and often show either TSC1 or TSC2 alterations, which result in the activation of the mTOR pathway, or TFE3 fusions. Given these molecular characteristics, mTOR inhibitors have recently been approved by the FDA in the treatment of malignant PEComas, particularly in those with TSC1/2 alterations. Therefore, molecular analyses may be helpful for both the diagnostic workup of …

Opa1 Disease-Causing Mutants Have Domain-Specific Effects On Mitochondrial Ultrastructure And Fusion, Benjamín Cartes-Saavedra, Daniel Lagos, Josefa Macuada, Duxan Arancibia, Florence Burté, Marcela K. Sjöberg-Herrera, María Estela Andrés, Rita Horvath, Patrick Yu-Wai-Man, György Hajnóczky, Verónica Eisner

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Inner mitochondrial membrane fusion and cristae shape depend on optic atrophy protein 1, OPA1. Mutations in OPA1 lead to autosomal dominant optic atrophy (ADOA), an important cause of inherited blindness. The Guanosin Triphosphatase (GTPase) and GTPase effector domains (GEDs) of OPA1 are essential for mitochondrial fusion; yet, their specific roles remain elusive. Intriguingly, patients carrying OPA1 GTPase mutations have a higher risk of developing more severe multisystemic symptoms in addition to optic atrophy, suggesting pathogenic contributions for the GTPase and GED domains, respectively. We studied OPA1 GTPase and GED mutations to understand their domain-specific contribution to protein function by analyzing …

The Mutational Landscape In Chronic Myelomonocytic Leukemia And Its Impact On Allogeneic Hematopoietic Cell Transplantation Outcomes: A Center For Blood And Marrow Transplantation Research (Cibmtr) Analysis, Matthew Mei, Raju Pillai, Soyoung Kim, Noel Estrada-Merly, Michelle Afkhami, Lixin Yang, Zhuo Meng, Muhammad Bilal Abid, Mahmoud Aljurf, Ulrike Bacher, Amer Beitinjaneh, Christopher Bredeson, Jean-Yves Cahn, Jan Cerny, Edward Copelan, Corey Cutler, Zachariah Defilipp, Miguel Angel Diaz Perez, Nosha Farhadfar, César O Freytes, Shahinaz M Gadalla, Siddhartha Ganguly, Robert Peter Gale, Usama Gergis, Michael R Grunwald, Betty K Hamilton, Shahrukh Hashmi, Gerhard C Hildebrandt, Hillard M Lazarus, Mark Litzow, Reinhold Munker, Hemant S Murthy, Sunita Nathan, Taiga Nishihori, Sagar S Patel, David Rizzieri, Sachiko Seo, Mithun Vinod Shah, Melhem Solh, Leo F Verdonck, Ravi Vij, Ronald M Sobecks, Betul Oran, Bart L Scott, Wael Saber, Ryotaro Nakamura

Department of Medical Oncology Faculty Papers

Somatic mutations are recognized as an important prognostic factor in chronic myelomonocytic leukemia (CMML). However, limited data are available regarding their impact on outcomes after allogeneic hematopoietic cell transplantation (HCT). In this registry analysis conducted in collaboration with the Center for International Blood and Marrow Transplantation Registry database/sample repository, we identified 313 adult patients with CMML (median age: 64 years, range, 28- 77) who underwent allogeneic HCT during 2001-2017 and had an available biospecimen in the form of a peripheral blood sample obtained prior to the start of conditioning. In multivariate analysis, a CMML-specific prognostic scoring system (CPSS) score of …