Though the function role of PRAF2 on cell apoptosis was not observed in tumors mentioned above, we found that knockdown of PRAF2 induced apoptosis of ESCC cells, and influenced the expression of apoptotic biomarkers which include BCL-XL, BAX, caspase3 and caspase9. This evidence concerns the gene BCL2L1 and esophageal squamous cell carcinoma.