Department of Gastroenterology, the Affiliated Changzhou No. 2 People's Hospital of Nanjing Medical University, Changzhou, 213000, China.
Department of Radiotherapy, Changzhou Tumor Hospital, Changzhou, China.
Radiat Res. 2023 Mar 1;199(3):264-272. doi: 10.1667/RADE-22-00126.1.
Recently, long noncoding RNAs (lncRNAs) and the Warburg effect have been reported to play important roles in the radio-sensitivity of tumor cells. Survival correlates with pathologic responses to chemoradiotherapy and improving responses to radiation may translate into improved survival. This study aims to examine the effects and mechanisms of lncRNA DGCR5 and the Warburg effect on ESCC cell radiosensitivity. Levels of DGCR5, miR-195 and hexokinase 2 (HK2) expression in ESCC tissues and cells were determined and their clinical significance was analyzed. TE-1 and KYSE150 cells received a 6 Gy dose of X-ray radiation and their survival, proliferation and apoptosis were evaluated using colony formation assays, CCK-8 assays, and flow cytometry, respectively. Lactic acid production and glucose consumption were also examined in both cell types. Finally, the expression of apoptotic proteins was assessed using Western blotting. Analysis revealed that DGCR5 and HK2 were overexpressed in ESCC, while miR-195 was under expressed. Moreover, it was demonstrated that down-regulation of DGCR5 inhibited cell proliferation and promoted apoptosis, resulting in increased radiosensitivity by inhibition of the Warburg Effect. Conversely, overexpression of DGCR5 exhibited an opposite phenomenon in vitro. When investigating the mechanism, we identified that miR-195 was predicted to be a direct downstream target of DGCR5. Meanwhile, HK2 was predicted to be a direct downstream target of miR-195. Dual-luciferase reporter assays verified the direct interaction between these molecules. Finally, in vivo experiments were utilized to validate that knockdown of DGCR5 suppressed the Warburg effect via targeting of the miR-195/HK2 axis to increase the radiosensitivity of ESCC. Our study reveals that down-regulation of DGCR5 resulted in inhibition of the Warburg effect through interaction with the miR-195/HK2 axis increasing ESCC cell apoptosis after irradiation, thus enhancing cell radiosensitivity.
最近，长链非编码 RNA（lncRNA）和瓦博格效应被报道在肿瘤细胞的放射敏感性中发挥重要作用。生存与放化疗的病理反应相关，提高对辐射的反应可能转化为生存的改善。本研究旨在探讨 lncRNA DGCR5 和瓦博格效应对 ESCC 细胞放射敏感性的影响及其机制。检测 ESCC 组织和细胞中 DGCR5、miR-195 和己糖激酶 2（HK2）的表达水平，并分析其临床意义。TE-1 和 KYSE150 细胞接受 6GyX 射线照射，通过集落形成实验、CCK-8 实验和流式细胞术分别评估细胞存活、增殖和凋亡，同时检测两种细胞类型的乳酸生成和葡萄糖消耗。最后，通过 Western blot 检测凋亡蛋白的表达。结果表明，DGCR5 和 HK2 在 ESCC 中高表达，而 miR-195 低表达。此外，下调 DGCR5 抑制细胞增殖并促进凋亡，通过抑制瓦博格效应增加放射敏感性。相反，体外过表达 DGCR5 则呈现相反的现象。在研究机制时，我们发现 miR-195 是 DGCR5 的直接下游靶标。同时，HK2 是 miR-195 的直接下游靶标。双荧光素酶报告基因实验验证了这些分子之间的直接相互作用。最后，体内实验验证了通过靶向 miR-195/HK2 轴抑制 DGCR5 敲低抑制瓦博格效应以增加 ESCC 放射敏感性。我们的研究表明，下调 DGCR5 通过与 miR-195/HK2 轴相互作用抑制瓦博格效应，增加照射后 ESCC 细胞凋亡，从而提高细胞放射敏感性。
