20540
A key to harnessing the enormous therapeutic potential of estrogens is understanding the diversity of estrogen receptors and their signaling mechanisms .
 Chemical: estrogens; Chemical: estrogen
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: estrogens, estrogen 
Answer:
 Chemical: estrogens; Chemical: estrogen