title: Quantitative assessment of HER2/neu expression by real-time PCR and fluorescent in situ hybridization analysis in low-grade osteosarcoma.
abstract: Low-grade osteosarcoma is a rare variant of osteosarcoma. Although malignant, it must be distinguished from conventional osteosarcomas because of its excellent prognosis. Numerous published papers have described the expression of HER2/neu oncogene in osteosarcoma as a poor prognostic factor; however their results are discordant. To address the expression of HER2/neu and to validate the assessment methods of amplification of the HER2/neu oncogene, the authors have employed quantitative real-time PCR and fluorencent in situ hybridization analysis (FISH) in 21 low-grade osteosarcomas. We calculated the quantification of HER2/neu oncogene amplification as the ratio of measured HER2/neu gene/beta-globin reference gene in real-time PCR. All 21 cases had amplified signals in the quantitative real-time PCR. However, in the FISH analysis, HER2/neu oncogene amplification was only identified in 26% (5/19). The exact reasons for the discordance between these two methods are unknown; however, variable histological features might play a potential role. In conclusion, as our study showed amplification of HER2/neu oncogene in low-grade osteosarcoma, we assume that expression of HER2/neu is not a poor prognostic factor in low-grade osteosarcoma.
authors.affiliation: Department of Laboratory Medicine, College of Medicine, Kyung Hee University, Seoul, Korea.
authors.forename: Woo-In
authors.initials: WI
authors.lastname: Lee
authors.forename: Patrizia
authors.initials: P
authors.lastname: Bacchni
authors.forename: Franco
authors.initials: F
authors.lastname: Bertoni
authors.forename: Young Hee
authors.initials: YH
authors.lastname: Maeng
authors.forename: Yong-Koo
authors.initials: YK
authors.lastname: Park
mesh_terms: D001483:Base Sequence; D001859:Bone Neoplasms / Q000235:genetics* / Q000473:pathology; D002455:Cell Division; D017931:DNA Primers; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007700:Kinetics; D012516:Osteosarcoma / Q000235:genetics* / Q000473:pathology; D016133:Polymerase Chain Reaction / Q000379:methods; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics*
chemical_list: D017931:DNA Primers; D018719:Erb-b2 Receptor Tyrosine Kinases