Quantitative assessment of HER2/neu expression by real-time PCR and fluorescent in situ hybridization analysis in low-grade osteosarcoma.
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.
Lee
Woo-In
WI
Department of Laboratory Medicine, College of Medicine, Kyung Hee University, Seoul, Korea.
Bacchni
Patrizia
P
Bertoni
Franco
F
Maeng
Young Hee
YH
Park
Yong-Koo
YK
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*
D017931:DNA Primers; D018719:Erb-b2 Receptor Tyrosine Kinases