Figure 2

Different patterns of genomic alterations detected by interphase FISH in prostate cancer. (a–c) Representative FISH images are shown for prostate cancer tissue microarray applying the TMPRSS2:ERG (left panel) and PTEN (right panel) probes. The left panel shows a representative pseudo-color image with the inverted-DAPI counterstained nuclei as a gray tone overlay to facilitate interpretation. The right panel shows a representative pseudo-color image with the DAPI counterstained nuclei. The rectangles show a enlarged nucleus FISH image. (a) Representative break-apart tri-color FISH strategy identifies the 5′ ERG BAC (RP11-95I21—green) well separated from the 3′ERG BAC (RP11-476D17—red) (arrow). The fused signal of the 3′ ERG (red) and TMPRSS2 gene locus (blue) that confirms the TMPRSS2:ERG fusion is arrowed used to detect TMPRSS2:ERG fusions (arrows). The BAC probes hybridizing to the unaffected TMPRSS2:ERG locus show the normal red-green (yellow) and blue colocalization pattern. This extreme nuclear separation is indicative of TMPRSS2:ERG rearrangements via genomic translocation mechanisms. Representative PTEN FISH image of homozygous deletion in prostate cancer shows absence of red signal for 10q23/PTEN locus in most of the nuclei and retained green signals for CEP 10. (b) The fused signal of the 3′ ERG (red) and TMPRSS2 gene locus (blue) that confirms the TMPRSS2:ERG fusion is arrowed. In addition, the hemizygous loss of 5′ ERG BAC (green) indicates an intervening genomic microdeletion of chromosome 21. The BAC probes hybridizing to the unaffected TMPRSS:ERG locus show the normal tri-color (red, green and blue) colocalization pattern. Representative PTEN FISH image of two signals of both red signals (10q23/PTEN locus) and green signals (CEP 10) in most of the nuclei indicating no deletion of PTEN in tumor cells. (c) Duplication of the fused signal of the 3′ ERG (red) and TMPRSS2 gene locus (blue) that confirms the TMPRSS2:ERG fusion is arrowed. In addition, the hemizygous loss of 5′ ERG BAC (green) indicates an intervening genomic microdeletion of chromosome 21. The BAC probes hybridizing to the unaffected TMPRSS:ERG locus show the normal tri-color (red, green and blue) colocalization pattern. The PTEN FISH image shows tumor cells with single red signal for 10q23/PTEN locus in most of the nuclei and paired green signals for CEP 10 indicating hemizygous deletion of 10q23/PTEN locus in prostate cancer.