Departments of Neurology (SMM), Neurologic Surgery (TEP, DJD, IFP), Health Sciences Research (JEE, PAD, JEEP), Medical Genome Analysis Core (VS); Immunology (IFP), Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN, 55905, USA.
Department of Pediatrics, Nationwide Children's Hospital, Columbus, OH, USA.
J Neurooncol. 2022 Jan;156(2):269-279. doi: 10.1007/s11060-021-03914-4. Epub 2022 Jan 5.
Medulloblastoma (MB) and diffuse infiltrative pontine glioma (DIPG) are malignant pediatric tumors. Extracellular vesicles (EVs) and their bioactive cargoes have been implicated in tumorigenesis. Most studies have focused on adult tumors, therefore the role of EVs and the noncoding RNA (ncRNA) landscape in pediatric brain tumors is not fully characterized. The overall aim of this pilot study was to isolate EVs from MB and DIPG patient-derived cell lines and to explore the small ncRNA transcriptome.
EVs from 3 DIPG and 4 MB patient-derived cell lines were analyzed. High-throughput next generation sequencing interrogated the short non-coding RNA (ncRNA) transcriptome. Known and novel miRNAs were quantified. Differential expression analysis, in silico target prediction, and functional gene enrichment were performed.
EV secretomes from MB and DIPG patient-derived cell lines demonstrated discrete ncRNA biotypes. Notably, miRNAs were depleted and Y RNAs were enriched in EV samples. Hierarchical cluster analysis revealed high discrimination in miRNA expression between DIPG and MB cell lines and RNA-Seq identified novel miRNAs not previously implicated in MB or DIPG pathogenesis. Known and putative target genes of dysregulated miRNAs were identified. Functional annotation analysis of the target genes for differentially expressed EV-and parental-derived miRNAs revealed significant cancer-related pathway involvement.
This hypothesis-generating study demonstrated that pediatric brain tumor-derived cell lines secrete EVs comprised of various ncRNA cargoes. Validation of these findings in patient samples may provide new insights into the pediatric brain tumor microenvironment and identification of novel therapeutic candidates.
髓母细胞瘤（MB）和弥漫性浸润性脑桥胶质瘤（DIPG）是恶性小儿肿瘤。细胞外囊泡（EV）及其生物活性货物已被牵涉到肿瘤发生中。大多数研究都集中在成人肿瘤上，因此 EV 和非编码 RNA（ncRNA）景观在小儿脑肿瘤中的作用尚未完全阐明。本初步研究的总体目的是从 MB 和 DIPG 患者来源的细胞系中分离 EV，并探索小 ncRNA 转录组。
分析了 3 个 DIPG 和 4 个 MB 患者来源的细胞系的 EV。高通量下一代测序分析了短非编码 RNA（ncRNA）转录组。定量了已知和新的 miRNAs。进行了差异表达分析、计算机预测靶标和功能基因富集。
MB 和 DIPG 患者来源的细胞系 EV 分泌谱显示出离散的 ncRNA 生物型。值得注意的是，miRNAs 被耗尽，而 Y RNAs 在 EV 样本中富集。层次聚类分析显示 DIPG 和 MB 细胞系之间 miRNA 表达存在高度差异，RNA-Seq 鉴定了先前未涉及 MB 或 DIPG 发病机制的新 miRNAs。鉴定了失调 miRNA 的已知和推测靶基因。差异表达的 EV 和亲本衍生 miRNA 的靶基因的功能注释分析显示，它们与癌症相关的途径显著相关。
这项产生假说的研究表明，小儿脑肿瘤来源的细胞系分泌的 EV 包含各种 ncRNA 货物。在患者样本中验证这些发现可能为小儿脑瘤微环境提供新的见解，并鉴定新的治疗候选物。
