14358
Numerous studies have shown that, upon HIV1 infection , human promonocytic U937 cells were induced to differentiate, as indicated, for example, by increased expression of adhesion molecules .
 ( cell line: U937 cells, None) , ( protein: adhesion molecules, None) , ( cell line: human promonocytic U937 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:
 ( cell line: U937 cells, None) , ( protein: adhesion molecules, None) , ( cell line: human promonocytic U937 cells, None) 