7301
In T lymphocytes , the hematopoietic cytokine interleukin-2 ( IL-2 ) uses phosphatidylinositol 3-kinase ( PI 3-kinase )-induced signaling pathways to regulate E2F transcriptional activity , a critical cell cycle checkpoint .
 interleukin-2, hematopoietic cytokine, PI 3-kinase, phosphatidylinositol 3-kinase, E2F, IL-2, T lymphocytes
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:
 interleukin-2, hematopoietic cytokine, PI 3-kinase, phosphatidylinositol 3-kinase, E2F, IL-2, T lymphocytes