24555
In cancers such as basal cell carcinoma ( BCC ) , ligand - independent mechanisms lead to constitutive Hh pathway activation through mutations in components of the pathway , including patched - 1 ( PTCH1 ) or smoothened ( SMO ) .
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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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