A preliminary study of the relationship between autophagy and metastasis of nasopharyngeal carcinoma cells after X?ray irradiation / 中华放射肿瘤学杂志

ABSTRACT

Objective To investigate the relationship between autophagy and metastasis of nasopharyngeal cancer ( NPC) cell lines 5?8F and 6?10B after X?ray irradiation and the related mechanism. Methods Two substrains, 5?8F and 6?10B, of the NPC cell line SUNE1, with high and low metastatic potentials, respectively, were used in our study. After 4 Gy X?ray irradiation, 5?8F cells were treated with rapamycin ( 20 μmol/L) to induce autophagy and 6?10B cells were treated with LY294002( 10μmol/L) to inhibit autophagy. The autophagy and metastatic activity of NPC cells were determined using qRT?PCR, Western blot, Transwell assay, laser confocal microscopy, and transmission electron microscopy. Results 5?8F cells showed a lower level of autophagy than 6?10B cells after X?ray irradiation. Rapamycin increased the autophagy and inhibited the metastasis of 5?8F cells after irradiation, while LY294002 inhibited the autophagy and increased the metastasis of 6?10B cells. Conclusions NPC 5?8F cells, which have a high metastatic potential, have a lower level of autophagy than 6?10B cells, which have a low metastatic potential. Autophagic inhibition could increase the metastatic activity of NPC cells, while autophagic activation could reduce their metastatic activity. Mechanistic analysis indicates that the PI3K/AKT/mTOR pathway is involved in this process.