9266
ATRA also induced expression of C/EBP epsilon protein in NB4 cells , as shown by Western blotting .
 ( cell line: NB4 cells, None) , ( protein: C/EBP epsilon protein, 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: NB4 cells, None) , ( protein: C/EBP epsilon protein, None) 