The role of circular RNA circSEPT9 in the radioresistance of glioma by targeting miR-432-5p
10.3760/cma.j.cn113030-20230518-00115
- VernacularTitle:环状RNA circSEPT9通过靶向miR-432-5p在胶质瘤放射抵抗中的作用研究
- Author:
Hao GU
1
;
Junqi LIU
;
Xin WANG
;
Ruitai FAN
Author Information
1. 郑州大学第一附属医院放疗科，郑州 450052
- Keywords:
circSEPT9;
Glioma;
miR-432-5p;
Radiation resistance;
Apoptosis
- From:
Chinese Journal of Radiation Oncology
2024;33(3):250-255
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the role of circular RNA (circRNA) circSEPT9 in the radioresistance of glioma and its molecular mechanism.Methods:Pathological samples were collected from 40 glioma patients who underwent surgery and postoperative radiotherapy in the First Affiliated Hospital of Zhengzhou University from January 2019 to January 2022. All patients were divided into the radiation-sensitive and radiation-resistant groups. The expression levels of circSEPT9 were assessed using real-time reverse transcription PCR (RT-qPCR) in two groups. The radiation-resistant glioma cell U251R was constructed based on human glioma cell U251. The U251R cells were divided into the negative control (si-NC), circSEPT9 knockdown (si-circSEPT9), negative control combined with irradiation (si-NC+4 Gy), circSEPT9 knockdown combined with irradiation (si-circSEPT9+4 Gy), circSEPT9 knockdown combined with control inhibitor and irradiation (si-circSEPT9+NC inhibitor+4 Gy), and circSEPT9 knockdown combined with miR-432-5p inhibitor and irradiation (si-circSEPT9+miR-432-5p inhibitor+4 Gy) groups. The targeting relationship between circSEPT9 and miR-432-5p was verified through dual-luciferase reporter assay. Colony formation assay was employed to assess the survival rate of U251R cells. Flow cytometry was adopted to measure the apoptosis rate. The expression level of circSEPT9 in glioma tissues was statistically analyzed using independent sample t-test. The survival and apoptosis rates in each group were evaluated using one-way ANOVA. Results:The expression level of circSEPT9 was up-regulated in the glioma tissues of patients in the radiation-resistant group (1.00±0.18 vs. 3.25±0.13, P<0.05). Compared to the si-NC group, the U251R cells in the si-circSEPT9 group exhibited a significant reduction in survival fraction and a notable increase in apoptosis rate (9.24±0.83 vs. 19.36±2.13, both P<0.05). After radiation exposure at 4, 6 and 8 Gy, si-circSEPT9 treatment significantly decreased the survival fraction in U251R cells (all P<0.05). Compared with the si-NC+4 Gy group, the apoptosis rate was increased in the si-circSEPT9+4 Gy group (18.83±1.94 vs. 35.23±3.56, P<0.05). Dual-luciferase reporter assay showed that circSEPT9 could target and negatively regulate the expression level of miR-432-5p. Compared with the si-circSEPT9+NC inhibitor+4 Gy group, the survival fraction of U251R was significantly increased in the si-circSEPT9+miR-432-5p inhibitor+4 Gy group ( P<0.05). Conclusion:Knockdown of circSEPT9 enhances the radiosensitivity of glioma cells by regulating cell apoptosis through targeting the miR-432-5p.
