This paper explored the application of RNA in cancer gene therapy. Second, the effect of the recombinant plasmid APE1 siRNA on the expression of APE1 protein was observed. In addition, the proliferation of cells in apoptosis and the radiosensitivity of human glioma U251 cells were also discussed. U251 cells were divided into control group, negative group and APE1siRNA group for culturing. There were two holes in each group, and independent experiments were repeated three times. The expression of APE1 protein in U251 cells was detected by Western blot experiments for siRNA transfection. The siRNA cells were transfected, while another group of FAM fluorescent labeled non-sense sequence siRNA was transfected to determine the transfection rate and extract the total protein of the cell. BCA protein assay kit was used for determining the concentration. Meanwhile, 50g sample and SDS-polypropylene diamine gel were prepared. Coomassie blue staining was used to observe the protein electrophoresis, after which the protein on the gel was transferred to the PVDF membrane and then developed in a chemiluminescent detection system with specific antibodies. The beta-action test was used as an internal controller, while the optical density scanner was used to detect the gray value of the target strip. The relative expression of target protein was equal to the target band gray value or the same sample reference value of gray. MTT method was used to detect the cell growth curve experiments, while A0 or EB method was used to detect the apoptosis rate of glioma cells. SPSS17.0 was used for statistical analysis. The results show that the APE1 siRNA expression plasmid was successfully introduced into human glioma cells by RNA interference, which can reduce the expression of APE1 in cells. It was confirmed that the reduction of APE1 protein could inhibit proliferation and promote the apoptosis of glioma cells. Third, APE1 targeting interference may be an effective gene therapy strategy for human glioma, which can provide an experimental basis for the clinical gene therapy of glioma.