1427
The reaction is enhanced by incubation of the tumor cells for 30 min at 37 degrees C prior to fixation.
 cell type: tumor cells
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
Answer:
 cell type: tumor cells