12308
In addition, extracellular factor (s) released by X-ray-treated human colonic carcinoma cell line ( HT29 ) might activate the long terminal repeat ( LTR ) of HIV-1 in non-irradiated HT29 cells .
 ( cell line: X-ray-treated human colonic carcinoma cell line, None) , ( DNA: LTR, None) , ( cell line: HT29, None) , ( cell line: non-irradiated HT29 cells, None) , ( protein: extracellular factor, None) , ( DNA: long terminal repeat, 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: X-ray-treated human colonic carcinoma cell line, None) , ( DNA: LTR, None) , ( cell line: HT29, None) , ( cell line: non-irradiated HT29 cells, None) , ( protein: extracellular factor, None) , ( DNA: long terminal repeat, None) 