A synthetic peptide corresponding to human Topoisomerase II alpha protein (within amino acids 1431-1531) was used as the immunogen for the Topo IIa antibody.
The topoisomerase II-Alpha isoform is a 170kDa nuclear protein and plays an important role in DNA synthesis and RNA transcription, as well as chromosomal segregation during mitosis. Topoisomerase II-Alpha is reported to be a sensitive and specific marker of late S-, G2- & M-phases in transformed and developmentally regulated normal cells, and has been shown to be over-expressed in many human cancers. Decreased expression of Topoisomerase II-Alpha is the predominant mechanism of resistance to several chemotherapeutic agents.