title: Identification of MYCN gene amplification in neuroblastoma using chromogenic in situ hybridization (CISH): an alternative and practical method.
abstract: Chromogenic in situ hybridization (CISH) is a recently developed technique, which utilizes the general principles of in situ hybridization and a detection system similar to immunohistochemistry. To assess the utility of CISH for analysis of MYCN gene amplification, we compared this assay with established diagnostic assays such as Southern blot analysis (SB) and fluorescent in situ hybridization (FISH). CISH was performed on 67 cases of neuroblastoma using tissue microarray (65 cases) and whole tissue sections (2 cases). Unequivocal, high-level amplification (> or =10 gene copies per tumor nucleus) was identified in 19 of 67 (28.4%) tumors. Two (3%) tumors showed low-level amplification (6-9 gene copies per tumor nucleus). No amplification was seen in 46 of 67 (68.6%) tumors. SB data were available in 44 tumors. Forty-one of the 44 tumors (93%) showed concordant results between CISH and SB. Three tumors showed MYCN amplification by CISH but no amplification by SB, most likely due to dilution effect of nonneoplastic tissue in the test samples. Two of these three tumors also showed MYCN amplification by FISH, and the third tumor was not analyzed by FISH. FISH data were available in total of 30 tumors. All 30 tumors showed concordant results between CISH and FISH for classifying a tumor as MYCN amplified or not amplified. We conclude that CISH is an accurate method for determining MYCN gene amplification, with added advantages that make it a more practically useful method.
authors.affiliation: Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA.
authors.forename: Rohit
authors.initials: R
authors.lastname: Bhargava
authors.forename: Orit
authors.initials: O
authors.lastname: Oppenheimer
authors.forename: William
authors.initials: W
authors.lastname: Gerald
authors.forename: Suresh C
authors.initials: SC
authors.lastname: Jhanwar
authors.forename: Beiyun
authors.initials: B
authors.lastname: Chen
mesh_terms: D002675:Child, Preschool; D002863:Chromogenic Compounds; D005784:Gene Amplification; D018628:Gene Dosage; D006801:Humans; D017403:In Situ Hybridization / Q000379:methods*; D007223:Infant; D007231:Infant, Newborn; D000071447:N-Myc Proto-Oncogene Protein; D009447:Neuroblastoma / Q000175:diagnosis* / Q000235:genetics; D009687:Nuclear Proteins / Q000235:genetics*; D015513:Oncogene Proteins / Q000235:genetics*; D010524:Peripheral Nervous System Neoplasms / Q000175:diagnosis* / Q000235:genetics; D046888:Tissue Array Analysis
chemical_list: D002863:Chromogenic Compounds; C459801:MYCN protein, human; D000071447:N-Myc Proto-Oncogene Protein; D009687:Nuclear Proteins; D015513:Oncogene Proteins