Brightfield in situ hybridization and dual color fluorescence in situ hybridization (FISH) for HER2 and CEN 17. HER2 and CEN 17 detection with formalin-fixed, paraffin-embedded xenograft tumors, MCF7 (non-amplified HER2 gene and chromosome 17 polysomy) (A, C, E, G) and BT-474 (amplified HER2 gene and chromosome 17 polysomy) (B, D, F, H). Normal HER2 gene signal is seen as black dots in the nuclei of MCF7 xenograft tumor (A) while amplified HER2 gene signal is seen as clusters of black dots in the nuclei of BT-474 tumor (B). CEN 17 signal is detected as red dots that are slightly larger than silver black dots (C, D). Double staining of HER2 gene and CEN 17 is obtained with silver grains and red dots (E, F). Individual HER2 gene and CEN 17 signals can be still recognized when both targets are co-localized (arrow heads, E). HER2 FISH signal is red-orange and CEN 17 FISH signal is green in the blue nuclei counterstained with DAPI (G, H). 100×.
Nitta et al. Diagnostic Pathology 2008 3:41 doi:10.1186/1746-1596-3-41