Application of CARD-ISH for assessment of numerical chromosome aberrationsin interphase nuclei of human tumor cells

In this study based on the study of a centromeric DNA probe specific for ch romosome 8 the authors standardized a method for the enzymatic detection of specific chromosome copy numbers on interphase nuclei from tumor tissue sa mples. Since the in situ hybridization (ISH) of chromosome 8 specific probe was revealed with a catalyzed reporter deposition (CARD),which allows a hi gh amplification of the hybridization signal, the method was designated as CARD-ISH. This method has been standardized on interphase nuclei isolated f rom clinical samples of pituitary adenomas, as well as on human normal lymp hocytes. On the same samples, they also evaluated chromosome 8 copy number distribution by FISH. Comparison between CARD-ISH and FISH results showed n o significant differences between the two methods, proposing CARD-ISH as a reliable alternative to FISH far chromosome numerical aberration assessment in laboratories that do not have specific facilities for epifluorescence m icroscopy or cytogenetics and that need a long-term storage of slides that had been used for diagnostic purposes.