11397
We have compared the action on U-937 human promonocytic leukemia cells of two DNA topoisomerase II inhibitors , namely the epipodophyllotoxin etoposide and the bisdioxopiperazine ICRF-193 .
 ( cell line: U-937 human promonocytic leukemia cells, None) , ( protein: DNA topoisomerase II, None) 
Locate the role in the text that participated in the event based on the event type and return it in the event list. 
 Option: Event type: RNA,cell type,protein,cell line,DNA, Arguments type: . 
Text: {0} 
Answer:
 ( cell line: U-937 human promonocytic leukemia cells, None) , ( protein: DNA topoisomerase II, None) 