30568
However , this serine / threonine kinase is now known to regulate numerous cellular processes through a number of signaling pathways important for cell proliferation , stem cell renewal , apoptosis and development .
 serine, threonine
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 serine, threonine