12068
To analyze the effects of ectopic expression of spi-1 on the proliferation/differentiation of human myeloid leukemia cells , K562 cells were stably transfected with a spi-1 expression vector .
 ( protein: spi-1, None) , ( cell type: human myeloid leukemia cells, None) , ( cell line: K562 cells, None) , ( DNA: spi-1 expression vector, None) , ( protein: spi-1, 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: spi-1, None) , ( cell type: human myeloid leukemia cells, None) , ( cell line: K562 cells, None) , ( DNA: spi-1 expression vector, None) , ( protein: spi-1, None) 