Radiation enhance biological activity of recombinant adeno-associated virus against human glioma through down-regulating ATM

Object Whether radiation can improve the biological activity of recombinant adeno-associated virus (rAAV) in U251 cells and the molecule mechanism. Methods ⁶⁰Co as the radiation resource to irradiate tumor cells; Inverted fluorescence microscope was performed to observe expression of EGFP; flow cytometry (FACS) analysis for transduction efficiency and mean fluorescent intensity; RT-PCR analysis for mRNA expression of rAAV binding receptors genes-HSPG, FGFR1 and Integrin, and DNA circularization related gene-ATM. Results Transduction efficiency don´t have a notable change after radiation. But the mean fluorescent intensity was improved with the rise of radiation dose. In mRNA expression level, the binding receptors for rAAV targeting cells, as well as ATM, have down-regulated. Conclusion Radiation can enhance biological activity of rAAV, and the enhance effect is not related to the “rAAV binding receptors” procedure. But down-regulation of ATM might affect this process.