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These results suggest that cdc2 mRNA expression is related to the cell cycling of normal human hematopoietic cells and that E2F plays some roles in the regulation of its expression.
 hematopoietic cells, cdc2 mRNA, E2F, normal human hematopoietic cells
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:
 hematopoietic cells, cdc2 mRNA, E2F, normal human hematopoietic cells