1900
It seems therefore that PGE2 , by elevating cAMP levels , interferes with the activation pathway for NF-kappa B but not for NF-AT , AP-1 or CLE0 binding protein .
 NF-kappa B, PGE2, AP-1, CLE0 binding protein, NF-AT
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
Answer:
 NF-kappa B, PGE2, AP-1, CLE0 binding protein, NF-AT