Institute of Radiation Medicine, Shanghai Medical College, Fudan University, Shanghai 200032, China.
School of Stomatology, Henan University, Kaifeng 475001, China.
Int J Mol Sci. 2023 Feb 3;24(3):3047. doi: 10.3390/ijms24033047.
Radioresistance remains a serious obstacle encountered in the radiotherapy of nasopharyngeal carcinoma (NPC). Both mRNAs and non-coding RNAs (ncRNAs), including long ncRNA (lncRNA) and microRNA (miRNA), play essential roles in radiosensitivity. However, the comprehensive expression profiles and competing endogenous RNA (ceRNA) regulatory networks among lncRNAs, miRNAs, and mRNAs in NPC radioresistance are still bewildering. In this study, we performed an RNA-sequencing (RNA-seq) assay in the radioresistant NPC cells CNE2R and its parental cells CNE2 to identify the differentially expressed lncRNAs, miRNAs, and mRNAs. The ceRNA networks containing lncRNAs, miRNAs, and mRNAs were predicted on the basis of the Pearson correlation coefficients and authoritative miRanda databases. In accordance with bioinformatic analysis of the data of the tandem mass tag (TMT) assay of CNE2R and CNE2 cells and the gene chip assay of radioresistant NPC samples in pre- and post-radiotherapy, the radioresistance-related signaling network of lncRNA CASC19, miR-340-3p, and FKBP5 was screened and further verified using an RT-qPCR assay. CASC19 was positively associated with FKBP5 expression while negatively correlated with miR-340-3p, and the target binding sites of CASC19/miR-340-3p and miR-340-3p/FKBP5 were confirmed using a dual-luciferase reporter assay. Moreover, using an mRFP-GFP-LC3 maker, it was found that autophagy contributed to the radioresistance of NPC. MiR-340-3p inhibition or FKBP5 overexpression could rescue the suppression of autophagy and radioresistance induced by CASC19 knockdown in CNE2R cells. In conclusion, the CASC19/miR-340-3p/FKBP5 network may be instrumental in regulating NPC radioresistance by enhancing autophagy, which provides potential new therapeutic targets for NPC.
放射抵抗仍然是鼻咽癌（NPC）放射治疗中遇到的严重障碍。mRNA 和非编码 RNA（ncRNA），包括长 ncRNA（lncRNA）和 microRNA（miRNA），在放射敏感性中发挥重要作用。然而，NPC 放射抵抗中 lncRNA、miRNA 和 mRNA 的综合表达谱和竞争内源性 RNA（ceRNA）调控网络仍然令人困惑。在这项研究中，我们对放射抵抗 NPC 细胞 CNE2R 及其亲本细胞 CNE2 进行了 RNA 测序（RNA-seq）分析，以鉴定差异表达的 lncRNA、miRNA 和 mRNA。基于 Pearson 相关系数和权威的 miRanda 数据库，预测了包含 lncRNA、miRNA 和 mRNA 的 ceRNA 网络。根据 CNE2R 和 CNE2 细胞的串联质量标签（TMT）分析数据的生物信息学分析以及放射前后 NPC 耐药样本的基因芯片分析，筛选并进一步验证了 lncRNA CASC19、miR-340-3p 和 FKBP5 的放射抵抗相关信号网络，采用 RT-qPCR 检测。CASC19 与 FKBP5 表达呈正相关，与 miR-340-3p 呈负相关，并且通过双荧光素酶报告基因检测证实了 CASC19/miR-340-3p 和 miR-340-3p/FKBP5 的靶结合位点。此外，使用 mRFP-GFP-LC3 标记物发现自噬有助于 NPC 的放射抵抗。miR-340-3p 抑制或 FKBP5 过表达可以挽救 CASC19 敲低在 CNE2R 细胞中诱导的自噬和放射抵抗的抑制作用。总之，CASC19/miR-340-3p/FKBP5 网络可能通过增强自噬来调节 NPC 放射抵抗，这为 NPC 提供了新的潜在治疗靶点。
