11644
The pro - inflammatory genes , interleukin - 6 ( Il - 6 ) , interleukin - 8 ( Il - 8 ) and tumor necrosis factor ( Tnf ) , and two aromatic hydrocarbon receptor - regulated genes , Cyp1a1 and 1b1 , were significantly up - regulated by oTRP .
 Chemical: aromatic hydrocarbon
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: aromatic hydrocarbon