Effect of combination of curcumin and GLUT-1 AS-ODN on radiosensitivity of laryngeal carcinoma through regulating autophagy

Background This study is to explore the role of curcumin and GLUT-1 antisense oligodeoxynucleotides (AS-ODN) on autophagy modulation-initiated radiosensitivity. Methods BALB/c mice were employed to establish xenograft model using Tu212 cell. The expression of autophagy- and apoptosis-related proteins was determined by WB. Autophagosome was observed under transmission electron microscope. Apoptosis of tumor tissue were detected by TUNEL staining. Results Combinations of curcumin and GLUT-1 AS-ODN with 10 Gy inhibited the tumor growth by inducing apoptosis of laryngeal cancer cells followed with the enhancement of autophagy. 3-MA also had a promotion effect on irradiation-mediated growth inhibition possibly by depressing PI3K and on curcumin/GLUT-1 AS-ODN-mediated growth inhibition potentially by regulating autophagic events. Of note, a de-escalation of radiotherapy dose (5 Gy) along with curcumin, GLUT-1 AS-ODN or 3-MA produced a stronger effect than high dosage of radiotherapy (10 Gy) alone. Conclusions Curcumin and GLUT-1 AS-ODN improve the radiosensitivity of laryngeal carcinoma through regulating autophagy and inducing apoptosis.