title: Patterns of spectrin expression in B-cell lymphomas: loss of spectrin isoforms is associated with nodule-forming and germinal center-related lymphomas.
abstract: Spectrins are a family of cytoskeletal proteins that organize and link membranes to subcellular motors and filaments. Although traditionally divided into erythroid and non-erythroid forms, the discovery of new spectrin isoforms in various tissues indicates that their distribution is not yet fully characterized. To our knowledge, there is no comprehensive analysis of spectrins in lymphoid malignancies. Using tumor microarrays of paraffin blocks, we immunohistochemically studied 10 lymph nodes with reactive lymphoid hyperplasia and 94 lymph nodes involved by B-cell malignant lymphoma. Expression of spectrins alphaI, alphaII, betaI, betaII, and betaIII was scored using a 20% cutoff for positive immunoperoxidase staining. All spectrin isoforms, except erythroid-specific alphaI spectrin, were detected in lymph nodes with reactive lymphoid hyperplasia. In contrast, various spectrins were lost in particular B-cell malignant lymphomas. Based on the absence of staining for one or more spectrin isoforms in at least 50% of cases, we identified three patterns: (1) loss of alphaII and betaII in follicular lymphoma, grades 2/3 and 3/3; nodular lymphocyte predominance Hodgkin's lymphoma; nodular sclerosis Hodgkin's lymphoma; (2) loss of betaI only in Burkitt lymphoma; and (3) loss of alphaII and betaI in mixed cellularity Hodgkin's lymphoma. In contrast, follicular lymphoma, grade 1/3 and diffuse large B-cell lymphoma retained spectrin in 67-100% of cases. The other lymphoma subtypes retained spectrin in greater than 50% of cases. We identified the loss of particular spectrin isoforms in B-cell malignant lymphomas that have a nodular growth pattern and/or are believed to arise from germinal center B-cells, that is follicular lymphoma, grades 2/3 and 3/3; Burkitt lymphoma; nodular sclerosis Hodgkin's lymphoma; mixed cellularity Hodgkin's lymphoma; and nodular lymphocyte predominance Hodgkin's lymphoma. The absence of particular spectrin isoforms may correlate with transformation or aggressive biologic behavior for some lymphoma subtypes.
authors: Department of Pathology, Montefiore Medical Center/Albert Einstein College of Medicine, Silver Zone, Bronx, NY, USA.
authors: Eric B
authors: EB
authors: Gorman
authors: Lugen
authors: L
authors: Chen
authors: Joseph
authors: J
authors: Albanese
authors: Howard
authors: H
authors: Ratech
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis; D002471:Cell Transformation, Neoplastic / Q000378:metabolism; D018858:Germinal Center / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D008198:Lymph Nodes / Q000378:metabolism / Q000473:pathology; D016393:Lymphoma, B-Cell / Q000378:metabolism* / Q000473:pathology*; D020033:Protein Isoforms / Q000378:metabolism; D012189:Retrospective Studies; D013049:Spectrin / Q000096:biosynthesis*; D046888:Tissue Array Analysis
chemical_list: D014408:Biomarkers, Tumor; D020033:Protein Isoforms; D013049:Spectrin