3100
Combined mutations of p27 ( - / - ) and Men1 ( + / - ) , in contrast , did not exhibit noticeable synergistic stimulation of Rb kinase activity , cell proliferation , and tumor growth .
 cell, tumor
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Anatomy 
Text: {0} 
Answer:
 cell, tumor