2580
A U87 rat xenograft model of GBM was used to investigate the regional distribution of erlotinib to the tumor , and brain regions surrounding the tumor .
 Chemical: erlotinib
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: erlotinib