5021
We show that the expression of PIM - 1 is induced in response to estradiol in MCF - 7 cells and that the induction is mediated by ER alpha - regulated enhancers located distally upstream from the gene .
 estradiol
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 estradiol