189
Here , we show that A549 / GR cells contain a high proportion of CXCR4 + cells that are responsible for having high potential of self - renewal activity in vitro and tumorigenicity in vivo .
 None
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities:  
Answer:
 None