Ott_a_275956 11627..11635

*These authors contributed equally to this work Purpose: To study the effect of β-elemene on the radiosensitivity of A549 cell xenograft tumor and potential mechanisms by which β-elemene regulates the expression of hypoxiainducible factor-1α (HIF-1α) and glucose transporter protein-1 (GLUT-1). Methods: Using an A549 cell transplantation tumor model with male nude mice, we studied the effect of β-elemene on the radiosensitivity of non-small cell lung cancer (NSCLC). The expression of HIF-1α and GLUT-1 was detected by real-time PCR, Western blotting and immunohistochemistry. The relationship between the radiosensitivity of β-elemene and the expression of HIF-1α and GLUT-1 was analyzed. Results: β-elemene and radiotherapy intervened in the growth of transplanted tumors in varying degrees. The enhancement factor (EF=2.44>1) was calculated; β-elemene at 45 mg/ kg had the most significant enhanced effect on radiosensitivity. When β-elemene was used in combination with radiation, the expression of HIF-1α and GLUT-1 was significantly decreased, and there was a positive correlation between the two genes. Conclusion: β-elemene exhibits a radiosensitizing effect on A549 cell xenograft tumor. The underlying molecular mechanism is probably associated with the down-regulation of HIF-1α and GLUT-1 expression, suggesting that β-elemene may directly or indirectly inhibit the expression of HIF-1α and GLUT-1. There is a positive significant correlation between expression of HIF-1α and GLUT-1. HIF-1α and downstream GLUT-1 could be used as a new target for the radiosensitization of NSCLC.