title: Actin isoform pattern expression: a tool for the diagnosis and biological characterization of human rhabdomyosarcoma.
abstract: The diagnosis and characterization of rhabdomyosarcoma requires the use of combined histological and immunohistochemical criteria due to the variety of its histological patterns. The identification of actin isoform expression is accepted as a useful adjunct to the diagnosis and classification of soft tissue tumors. Using a new antibody specific for alpha-cardiac actin, obtained according to a recently described strategy for the production of polyclonal antibodies against actin isoforms [9], we have analyzed a series of 17 rhabdomyosarcomas, including all histological subtypes. In addition, we have evaluated the presence in these tumors of alpha-skeletal and alpha-smooth muscle actins. All specimens examined revealed a positive immunostaining for alpha-cardiac actin. Tumoral cells of eight cases also expressed alpha-smooth muscle actin and only three cases (all embryonal subtypes) were positive for alpha-skeletal actin. Our results indicate that immunohistochemical screening for alpha-cardiac actin expression is a useful tool for the diagnosis of rhabdomyosarcoma. They also suggest that the expression of alpha-skeletal actin is valuable in determining the subtype and possibly the state of differentiation of these tumors.
authors.affiliation: Department of Pathology, University of Geneva, 1 rue Michel-Servet, 1211 Geneva 4, Switzerland.
authors.forename: Sophie
authors.initials: S
authors.lastname: Clément
authors.forename: Augusto
authors.initials: A
authors.lastname: Orlandi
authors.forename: Leonardo
authors.initials: L
authors.lastname: Bocchi
authors.forename: Gianpaolo
authors.initials: G
authors.lastname: Pizzolato
authors.forename: Maria Pia
authors.initials: MP
authors.lastname: Foschini
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Eusebi
authors.forename: Giulio
authors.initials: G
authors.lastname: Gabbiani
mesh_terms: D000199:Actins / Q000276:immunology / Q000378:metabolism*; D000293:Adolescent; D000328:Adult; D014408:Biomarkers, Tumor; D002648:Child; D002675:Child, Preschool; D003893:Desmin / Q000378:metabolism; D018572:Disease-Free Survival; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D006801:Humans; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged; D020033:Protein Isoforms; D018232:Rhabdomyosarcoma, Alveolar / Q000145:classification / Q000378:metabolism* / Q000473:pathology; D018233:Rhabdomyosarcoma, Embryonal / Q000145:classification / Q000378:metabolism* / Q000473:pathology; D012983:Soft Tissue Neoplasms / Q000378:metabolism* / Q000473:pathology
chemical_list: D000199:Actins; D014408:Biomarkers, Tumor; D003893:Desmin; D020033:Protein Isoforms