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Based on sequence homology we identified two binding motifs for Pit-1 and seven half-sites for glucocorticoid receptor/progesterone receptor ( PR ) binding .
 PR, binding motifs, Pit-1, half-sites, glucocorticoid receptor/progesterone receptor
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:
 PR, binding motifs, Pit-1, half-sites, glucocorticoid receptor/progesterone receptor