Objective:To evaluate the effects of down regulating hepatoma-derived growth factor (HDGF) of glioma on the proliferation and apoptosis of U373 cells.Methods:siRNA targeting human HDGF gene was designed and transfected transiently into U373 cells by lipofectamine. RT-PCR and Western blot were used to detect the changes in expressions of HDGF gene and protein as well as to evaluate the efficacy of RNA interference. Flow cytometric detection and MTT method were used to detect cell apoptosis and proliferation. Results:RT-PCR and Western blot results showed that the expressions of HDGF gene and protein declined obviously in U373 cells at 48 hours after the transfection. Meanwhile

the MTT results indicated that the proliferation in vitro was remarkably decreased and the apoptosis rate was significantly increased in U373 cells compared with those in blank and negative control group after down regulating HDGF expressions (P<0.01 andP<0.05). Conclusion:HDGF plays a conductive role in the development of glioma

which may become a new molecular marker in tumor diagnosis and treatment.