15192
INTRODUCTION : One of the hallmarks of cancer cells is the inactivation of the p53 pathway either due to mutations in the p53 gene or over - expression of negative regulators , Mdm2 and / or MdmX .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
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