Abstract: Objective:To discuss the biological significance of ITSN1-S in regulating proliferation and apoptosis of glio -blastoma cells and to further explore the possible molecular mechanisms. Methods:Small interfering RNA (siRNA) technol -ogy was applied to inhibit the expression of ITSN 1-S in the glioma cell line LN- 229 . MTT assay, flow cytometry and TUNEL assay were performed to determine cell proliferation and apoptosis. Western blotting was used to detect the expression of apoptosis-related proteins, Bad and Bcl-2. Results: Compared with the control group, there was apparent inhibition of cell proliferation in the transfected group, with an increase of apoptosis. The expression of anti-apoptotic protein Bcl-2 was down-regulated while the expression of apoptosis-promoter protein Bad was up-regulated. Conclusion:ITSN1-S is involved in regulating the proliferation and apoptosis of glioma cells by regulating the expression of the apoptosis-related proteins.