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This was in sharp contrast to endometrial cells where 3 kb 5'-flanking DNA conferred strong transcriptional activation on the dPRL promoter in decidualized endometrial stromal cells actively secreting PRL , but did not allow transcription in undifferentiated non-PRL-secreting endometrial stromal cells .
 PRL, non-PRL-secreting endometrial stromal cells, endometrial stromal cells, dPRL promoter
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:
 PRL, non-PRL-secreting endometrial stromal cells, endometrial stromal cells, dPRL promoter