Measurement of Drug-Stabilized Topoisomerase II Cleavage Complexes by Flow Cytometry

Curr Protoc Cytom. 2017 Jul 5:81:7.48.1-7.48.8. doi: 10.1002/cpcy.21.

Abstract

The poisoning of Topoisomerase II (Top2) has been found to be useful as a therapeutic strategy for the treatment of several tumors. The mechanism of Top2 poisons involves a drug-mediated stabilization of a Top2-DNA complex, termed Top2 cleavage complex (Top2cc), which maintains a 5' end of DNA covalently bound to a tyrosine from Top2 through a phosphodiester group. Drug-stabilized Top2cc leads to Top2-linked-DNA breaks, which are believed to mediate their cytotoxicity. Several time-consuming or cell type-limiting assays have been used in the past to study drug-stabilized Top2cc. Here, we describe a flow cytometry-based method that allows a rapid assessment of drug-induced Top2cc, which is suitable for high throughput analysis in almost any kind of human cell. The analyses of the drug-induced Top2cc in the cell cycle context and the possibility to track its removal are additional benefits from this methodology. © 2017 by John Wiley & Sons, Inc.

Keywords: high-throughput analysis; human cells; topoisomerase II cleavage complexes.

MeSH terms

  • Animals
  • DNA / analysis*
  • DNA / chemistry
  • DNA / metabolism
  • DNA Topoisomerases, Type II / analysis*
  • DNA Topoisomerases, Type II / chemistry
  • DNA Topoisomerases, Type II / metabolism
  • Etoposide / chemistry*
  • Etoposide / pharmacology
  • Flow Cytometry / methods*
  • HL-60 Cells
  • Humans

Substances

  • Etoposide
  • DNA
  • DNA Topoisomerases, Type II