7471
Treatment with E2 or Prog increased survival and prevented apoptosis induced by TNF-alpha in both undifferentiated and macrophage-like PMA-differentiated U937 cells , as assessed by trypan blue exclusion cell counting , thymidine incorporation , AnnexinV labeling , followed by flow cytometry and DNA fragmentation studies .
 ( protein: TNF-alpha, None) , ( cell line: PMA-differentiated 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:
 ( protein: TNF-alpha, None) , ( cell line: PMA-differentiated U937 cells, None) 