11665
The transduction pathway leading to NF-kappaB activation in U937 cells involved the intracellular generation of reactive oxygen species ( ROS) , as demonstrated by the concomitant inhibitory effects of antioxidants on NF-kappaB activation and the emission of a fluorescent probe reacting intracellularly with hydrogen peroxide .
 ( cell line: U937 cells, None) , ( protein: NF-kappaB, None) , ( protein: NF-kappaB, 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: U937 cells, None) , ( protein: NF-kappaB, None) , ( protein: NF-kappaB, None) 