2722
Neutral sphingomyelinase ( SMase ) can be activated by extracellular signals to produce ceramide , which may affect mitogen-activated protein kinase ( MAPK ) activities .
 protein: Neutral sphingomyelinase; protein: SMase; protein: mitogen-activated protein kinase; protein: MAPK
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
 Entities: Neutral sphingomyelinase, SMase, mitogen-activated protein kinase, MAPK 
Answer:
 protein: Neutral sphingomyelinase; protein: SMase; protein: mitogen-activated protein kinase; protein: MAPK