4744
ML-9 induced nitroblue tetrazolium ( NBT )-reducing activity of U937 cell more rapidly than VD3 : This differentiation marker was induced significantly after incubation with ML-9 and VD3 for 4 hours and 1 day, respectively.
 cell line: U937 cell
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
 Entities: U937 cell 
Answer:
 cell line: U937 cell