The Third Department of Surgery, The Fourth Hospital of Hebei Medical University, Shijiazhuang, 050011, China.
Hebei Key Laboratory of Metabolic Disease, Shijiazhuang, 050011, China.
J Nanobiotechnology. 2024 Sep 14;22(1):563. doi: 10.1186/s12951-024-02826-5.
While small extracellular vesicles (sEVs)-derived circular RNAs (circRNAs) have been emerged as significant players in cancer, the function and underlying mechanism of sEVs-derived circRNAs in anti-cancer immunity remain unclear.
Gastric cancer (GC)-derived circRNAs were identified using RNA-seq data from GEO datasets and quantitative reverse transcription polymerase chain reaction (qRT-PCR), RNA immunoprecipitation, dual-luciferase assay, and bioinformatics analysis were performed to investigate the regulatory axis. Transwell assay, wound healing assay, cell counting kit-8 (CCK-8) assay, and xenograft models were used to evaluate its role in GC progression in vivo and in vitro. The delivery of specific circRNAs into sEVs were verified through electron microscopy, nanoparticle tracking analysis (NTA) and fuorescence in situ hybridization (FISH). Flow cytometric analysis and immunohistochemical staining were conducted to find out how specific circRNAs mediated CD8 T cell exhaustion and resistant to anti-programmed cell death 1 (PD-1) therapy.
We identified that circ_0001947, packaged by GC-derived sEVs, was obviously elevated in GC and was associated with poor clinical outcome. High circ0001947 level augmented the proliferation, migration, and invasion of GC cells. Mechanistically, circ0001947 sponged miR-661 and miR-671-5p to promote the expression of CD39, which further facilitated CD8 T cell exhaustion and immune resistance. Conversely, blocking circ_0001947 attenuated CD8 T cell exhaustion and increased the response to anti-PD-1 therapy.
Our study manifested the therapeutic potential of targeting sEVs-transmitted circ_0001947 to prohibit CD8 T cell exhaustion and immune resistance in GC.
虽然小细胞外囊泡 (sEVs)-衍生的环状 RNA (circRNA) 已成为癌症中的重要参与者，但 sEVs 衍生的 circRNA 在抗癌免疫中的功能和潜在机制仍不清楚。
使用 GEO 数据集的 RNA-seq 数据和定量逆转录聚合酶链反应 (qRT-PCR) 鉴定胃癌 (GC) 衍生的 circRNA，进行 RNA 免疫沉淀、双荧光素酶报告基因检测、生物信息学分析等实验来研究调控轴。Transwell 实验、划痕实验、细胞计数试剂盒-8 (CCK-8) 实验和异种移植模型用于评估其在体内和体外 GC 进展中的作用。通过电子显微镜、纳米颗粒跟踪分析 (NTA) 和荧光原位杂交 (FISH) 验证特定 circRNA 在 sEV 中的递呈。流式细胞术分析和免疫组织化学染色用于研究特定 circRNA 如何介导 CD8+T 细胞耗竭和对抗程序性细胞死亡 1 (PD-1) 治疗的耐药性。
我们发现，GC 来源的 sEVs 包裹的 circ_0001947 在 GC 中明显升高，与不良临床结局相关。高水平的 circ0001947 增强了 GC 细胞的增殖、迁移和侵袭。机制上，circ0001947 作为 miR-661 和 miR-671-5p 的海绵体，促进 CD39 的表达，进而促进 CD8+T 细胞耗竭和免疫抵抗。相反，阻断 circ_0001947 可减弱 CD8+T 细胞耗竭并增加对抗 PD-1 治疗的反应。
我们的研究表明，靶向 sEV 传递的 circ_0001947 以阻止 GC 中 CD8+T 细胞耗竭和免疫抵抗具有治疗潜力。
