6188
In this study, we investigate the role of TNFalpha -inducible reactive oxygen species (ROS) in IL-8 expression by "monocyte-like" U937 histiocytic lymphoma cells .
 ( protein: IL-8, None) , ( protein: TNFalpha, None) , ( cell line: U937 histiocytic lymphoma cells, 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:
 ( protein: IL-8, None) , ( protein: TNFalpha, None) , ( cell line: U937 histiocytic lymphoma cells, None) 