title: Differential KIT expression in histological subtypes of adenoid cystic carcinoma (ACC) of the salivary gland.
abstract: Adenoid cystic carcinoma (ACC) of the salivary gland is characterized by a prolonged but inevitably unfavorable clinical course. Recent studies suggested the transmembrane tyrosine kinase KIT to be involved in ACC pathogenesis. To investigate KIT expression in histologically defined subgroups of ACC and to clarify whether KIT gene copy number gain contributes to KIT overexpression, tumor tissue microarray sections including 55 ACC tumors were analyzed by fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC). The prevalence of positive KIT immunostaining was 89% (49/55). Strong immunostaining of KIT was only found in cribriform and tubular but never in solid subtypes (p=0.02). Average KIT staining intensity was higher in cribriform and tubular (n=37) compared to solid (n=18) ACC subtypes (p=0.005). FISH analysis revealed copy number gains of the KIT gene in 6.1% (3/49) of tumors analyzed. Our results implicate that specific KIT tyrosine kinase inhibitors such as imatinib, might be used in future therapeutic approaches against subgroups of ACC.
authors.affiliation: Abteilung Molekulare Genetik (B060), Deutsches Krebsforschungszentrum, 69120 Heidelberg, Germany.
authors.forename: Kolja
authors.initials: K
authors.lastname: Freier
authors.forename: Christa
authors.initials: C
authors.lastname: Flechtenmacher
authors.forename: Axel
authors.initials: A
authors.lastname: Walch
authors.forename: Frauke
authors.initials: F
authors.lastname: Devens
authors.forename: Joachim
authors.initials: J
authors.lastname: Mühling
authors.forename: Peter
authors.initials: P
authors.lastname: Lichter
authors.forename: Stefan
authors.initials: S
authors.lastname: Joos
authors.forename: Christof
authors.initials: C
authors.lastname: Hofele
mesh_terms: D003528:Carcinoma, Adenoid Cystic / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D046228:Microarray Analysis / Q000379:methods; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism*; D012468:Salivary Gland Neoplasms / Q000235:genetics / Q000378:metabolism*
chemical_list: D019009:Proto-Oncogene Proteins c-kit