Experimental study of APE1 RNA interference enhancing the sensitivity of neutron radiation in osteosarcoma

Objective: To knock down APE1 gene expression in HOS cells, and explore its antitumor effects in combination with 252Cf neutron radiotherapy. Methods: pSilence APE1 siBNA plasmid was transfected into HOS cells by SuperFect Transfection liposome. The transfected HOS cells were irradiated by 252Cf neutron, then MTY assay, clone formation assay and alkaline comet assay were used to detect the radiobiological reaction, and cell apoptosis was detected with flow cytometry. Results: The D37 value was 3.02 vs. 2.42 in the control and transfected HOS cells respectively after irradiation with 252Cf neutron, the DMF value is 1.43. The tail moments and cell apoptosis rate at 200, 500 and 1000 cGy showed significant difference between the two groups (P<0.05). Conclusions: pSilence APE1 may significantly sensitize the neutron radiotherapy of the HOS cells, and enhance DNA damage and cell apoptosis. Therefore, the gene therapy with pSilence APE1 combined 252Cf neutron radiotherapy may be a promising approach to therapy of human osteosarcoma in the future. (authors)