title: Alpha-synuclein expression in central nervous system tumors showing neuronal or mixed neuronal/glial differentiation.
abstract: Alpha-synuclein (alpha-synuclein) is a member of a family of cytoplasmic proteins found predominantly and abundantly in the brain, and concentrated in pre-synaptic nerve terminals, near vesicles. We hypothesized that an antibody to alpha-synuclein could be a useful marker of neuronal differentiation in central nervous system (CNS) tumors. Twenty tumors known to have neuronal or mixed neuronal/glial differentiation ( 11 gangliogliomas, 2 anaplastic gangliogliomas, 5 gangliocytomas, and 2 ganglioneuroblastomas), 5 central neurocytomas, and 1 dysembryoplastic neuroepithelial tumor (DNET) were immunostained with a mouse monoclonal antibody raised against human alpha-synuclein. Intense cytoplasmic staining, in some instances extending into the perikarya, was seen in 6 of 11 gangliogliomas, 2 of 2 anaplastic gangliogliomas, and 2 of 2 ganglioneuroblastomas. Alpha-synuclein-positive cells were usually large in size, resembled dysmorphic neurons, and were variably immunoreactive for anti-neurofilament and/or anti-synaptophysin antibodies. In contrast, central neurocytomas, gangliocytomas, and the DNET were negative for cytoplasmic alpha-synuclein expression. Our findings indicate that alpha-synuclein is expressed within the neuronal component of mixed tumors of the CNS displaying more than 1 histophenotype, and/or showing different degrees of anaplasia. Based on currently available data, we conclude that cytoplasmic alpha-synuclein expression is a marker of maturing neurons in these tumors.
authors.affiliation: Department of Pathology, University of Texas Southwestern Medical Center, Dallas 75235-9073, USA.
authors.forename: R
authors.initials: R
authors.lastname: Raghavan
authors.forename: C L
authors.initials: CL
authors.lastname: White
authors.forename: B
authors.initials: B
authors.lastname: Rogers
authors.forename: C
authors.initials: C
authors.lastname: Coimbra
authors.forename: E J
authors.initials: EJ
authors.lastname: Rushing
mesh_terms: D002454:Cell Differentiation; D016543:Central Nervous System Neoplasms / Q000378:metabolism* / Q000473:pathology*; D018303:Ganglioglioma / Q000378:metabolism / Q000473:pathology; D018305:Ganglioneuroblastoma / Q000378:metabolism / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D018241:Neuroectodermal Tumors, Primitive, Peripheral / Q000378:metabolism / Q000473:pathology; D009457:Neuroglia / Q000473:pathology*; D009474:Neurons / Q000473:pathology*; D051843:Synucleins; D051844:alpha-Synuclein
chemical_list: D009419:Nerve Tissue Proteins; C497604:SNCA protein, human; D051843:Synucleins; D051844:alpha-Synuclein