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Our results reveal an aspect of the precise molecular mechanisms of some breast cancers , in which full invasiveness is not acquired just by intracellular alterations of cancer cells , but extracellular factors from microenvironments may also be necessary .
 breast cancers, intracellular, cancer cells, extracellular
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Anatomy 
Text: {0} 
Answer:
 breast cancers, intracellular, cancer cells, extracellular