Liquiritigenin Enhances the Radiosensitivity of Nasopharyngeal Carcinoma Cell by Affecting Its Autophagy

Abstract

Objective: To investigate the effect of licorice on radiosensitization of nasopharyngeal carcinoma cells and its mechanism. Methods: MTT assay was used to detect the effect of different concentrations of glycyrrhizin on the activity of nasopharyngeal carcinoma cells. The changes of autophagy were observed by transmission electron microscopy (TEM) in the treatment of nasopharyngeal carcinoma cells. Western blotting was used to detect the effect of glycyrrhizin on the level of autophagy protein in nasopharyngeal carcinoma. Flow cytometry was used to detect the changes of apoptosis rate of nasopharyngeal carcinoma cell line after radiotherapy. Results: After successfully constructing CNE-2-RR radiation resistant cell line, MTT assay was used to detect the best inhibition rate of 20 mmol/L glycyrrhizin on nasopharyngeal carcinoma (58.86 ± 5.02)%. Transmission electron microscopy showed that the number of autophagosomes increased and the mitochondria and nuclei were abnormal in the treatment of nasopharyngeal carcinoma cells. Western Blotting was used to detect the increase of LC3-II level and the decrease of LC3-I level in nasopharyngeal carcinoma cells of 20 mmol/L concentration group. Conclusion: Glycyrrhizin enhances its sensitivity to radiotherapy by influencing autophagy and DNA repair ability of nasopharyngeal carcinoma cells.