17637
In our previous study , we identified the estrogen receptor alpha ( ER alpha ) as a relevant enhancer of leptin - induced signal transduction leading to transactivation of signal transducer and activator of transcription 3 ( Stat3 ) .
 Chemical: estrogen
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: estrogen