FIGURE 1

A, high-level amplification of c-MYC identified by fluorescence in situ hybridization by using the Tyramide Signal Amplification system. Hybridization was performed with a c-MYC–specific probe (red signals) and a chromosome 8 centromeric probe (green signals). The picture shows one tumor nucleus with three clusters of c-MYC signals (red) and two green spots representing chromosome 8 (not all signals in focus). Nuclei were counterstained with DAPI. B, low-level gain of c-MYC in another pancreatic carcinoma showing five c-MYC signals (red) in relation to two chromosome 8 signals (green).