5016
Unexpectedly, expression of the same EBNA2 -oestrogen receptor fusion protein in established human B cell lymphoma lines resulted in growth retardation or growth arrest upon the addition of oestrogen .
 ( cell line: established human B cell lymphoma lines, None) , ( protein: EBNA2, 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: established human B cell lymphoma lines, None) , ( protein: EBNA2, None) 