21240
In addition , transfection of HepG2 cells with siRNA targeting the human HO - 1 gene reversed the MeHg - mediated inhibition of TCDD - induced CYP1A1 .
 Chemical: MeHg; Chemical: TCDD
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: MeHg; Chemical: TCDD