We have studied the phosphorylation of DNA topoisomerases II in HeLa cells focusing on the β isoform of the enzyme which is very difficult to analyze because of its instability. In proliferating cells, we observed that both the α and β isozymes are labeled after cell incubation with 32P. The phosphorylation of β enzyme occurs to a low extent, thus reflecting the expression of topoisomerases II during cell cycle. In cells treated with etoposide, the activity of topoisomerase II is inhibited and the level of phosphorylation decreases, suggesting a possible cooperation between this modification and drug response.
|Number of pages||6|
|Journal||International Journal of Oncology|
|Publication status||Published - 1995|
- DNA topoisomerase II α and β
ASJC Scopus subject areas
- Cancer Research