1730
To elucidate the biological role of the endogenous angiogenesis inhibitor thrombospondin - 2 ( TSP - 2 ) during multistep carcinogenesis , we subjected TSP - 2 - deficient and wild - type mice to a chemical skin carcinogenesis regimen .
 skin
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Anatomy 
Text: {0} 
Answer:
 skin