4552
The ability to positively and negatively regulate many of these pathways , combined with feedback signalling from these pathways to p53 , demonstrates the reciprocal and flexible nature of the regulation , facilitating a diverse range of responses to metabolic stress .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Anatomy 
Text: {0} 
Answer:
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