LSI TOP2A (Orange)

« back

Probe location


Probe description

The LSI TOP2A FISH kit is intended for the determination of TOP2A gene status in human tissues using fluorescence in situ hybridization (FISH).
The LSI TOP2A FISH kit contains a directly labeled fluorescent DNA probe in hybridization buffer. The fluorochrome Orange labeled TOP2A probe covers the chromosome 17q21 region.
The TOP2A (DNA topoisomerase 2-alpha) gene encodes DNA topoisomerase II-alpha, which is involved in processes such as replication, transcription, chromosome condensation and chromatids separation. TOP2A amplification is frequent in breast cancers and occurs also with Her-2/neu amplification. TOP2A, Her-2/neu genes co-amplification can be a useful predictive marker of responsiveness to anthracycline based chemotherapy regiments.

FISH results

A normall cell shows 2 copies (orange signals) of TOP2A gene (1a). An abnormal cell shows higher copy number (more than 20 orange signals) of TOP2A gene (1b).

A normal cell hybridized with the LSI TOP2A (Orange) shows 2 orange signals of the TOP2A gene. An abnormal cell hybridized with the LSI TOP2A (Orange) shows more than 20 orange signals which indicate the amplification of TOP2A gene.
1a 1b

Figure1. The assessment of TOP2A gene copy number (breast cancer patient FFPE tissue).
1a. 2 copies of TOP2A gene in normal cell.
1b. Higher copy number of TOP2A gene in an abnormal cell.



Catalogue number

Packing size


Information for use

LSI TOP2A (Orange)



upon request



  • Hurley LH: DNA and its associated processes as targets for cancer therapy. Nat Rev Cancer 2002; 2: 188-200. [fulltext]
  • Keith WN, Douglas F, Wishart GC, McCallum HM, George WD, Kaye SB, Brown R: Co-amplification of erbB2, topoisomerase II a and retinoic acid receptor a genes in breast cancer and allelic loss of topoisomerase I on chromosome 20. Eur J Cancer 1993; 29A(10): 1469-1475. [fulltext]
  • Murphy DS, McHardy P, Coutts J, Mallon EA, George WD, Kaye SB, Brown R, Keith WN: Interphase cytogenetic analysis of erbB2 and topoIIa co-amplification in invasive breast cancer and polysomy of chromosome 17 in ductal carcinoma in situ. Int J Cancer 1995; 64: 18-26. [fulltext]
  • Nitiss JL, Beck WT: Antitopoisomerase drug action and resistance. Europ J Cancer 1996; 32A(6): 958-966. [fulltext]
  • Shimizu T, Pommier Y: DNA fragmentation induced by protease activation in p53-null human leukemia HL60 cells undergoing apoptosis following treatment with the topoisomerase I inhibitor camptothecin: cell-free system studies. Exp Cell Res 1996; 226: 292-301. [fulltext]