Table_1_Exosome-transmitted miR-3124-5p promotes cholangiocarcinoma development via targeting GDF11.docx

ObjectiveCholangiocarcinoma (CHOL) is a deadly cancer worldwide with limited available therapies. The aim of this study was to investigate key exosomal miRNAs and their functions in CHOL development.
MethodsSerum exosomes were isolated from patients with CHOL and healthy controls, followed by miRNA sequencing for identifying differentially expressed miRNAs (DEMs) and their functions. Then, the expression of key DEMs was experimentally validated in exosomes from clinical CHOL patients and CHOL cells. The effects of overexpression of key DEMs on CHOL cell migration and proliferation were investigated. A key exosomal DEM miR-3124-5p was identified. The effects of overexpression or knockdown of exosomal miR-3124-5p on the proliferation, migration, and angiogenesis of human umbilical vein endothelial cells (HUVECs) were investigated. Moreover, the function of exosomal miR-3124-5p on tumor growth in vivo was explored.
ResultsA total of 632 exosomal DEMs were identified between CHOL and control samples. Target genes of DEMs were significantly enriched in pathways, such as the p53 signaling pathway. miR-3124-5p was upregulated in serum exosomes from CHOL patients and exosomes from CHOL cells, and overexpression of miR-3124-5p promoted RBE cell migration and viability. Moreover, overexpression of exosomal miR-3124-5p promoted the proliferation, migration, and angiogenesis of HUVECs, while knockdown of miR-3124-5p had the opposite effect. miR-3124-5p could target growth differentiation factor 11 (GDF11) and downregulate GDF11 expression. Furthermore, exosomal miR-3124-5p promoted tumor growth in vivo.
ConclusionsOur findings revealed that exosome-encapsulated miR-3124-5p promoted the malignant progression of CHOL by targeting GDF11. Exosomal miR-3124-5p and GDF11 could be promising biomarkers or therapeutic targets for CHOL.

### 研究目的
胆管癌（Cholangiocarcinoma, CHOL）是全球范围内致死率极高且可用治疗手段有限的恶性肿瘤。本研究旨在探究胆管癌发生发展过程中的关键外泌体微小RNA（exosomal miRNAs）及其生物学功能。

### 研究方法
本研究从胆管癌患者及健康对照者的血清中分离外泌体，通过微小RNA测序鉴定差异表达微小RNA（differentially expressed miRNAs，DEMs）并预测其功能。随后，在临床胆管癌患者血清外泌体及胆管癌细胞来源外泌体中，对关键DEMs的表达水平进行实验验证。此外，考察了关键DEMs过表达对胆管癌细胞迁移与增殖能力的影响。最终，本研究鉴定出关键外泌体DEM miR-3124-5p，并分别探究了该外泌体miR-3124-5p过表达或敲低对人脐静脉内皮细胞（human umbilical vein endothelial cells，HUVECs）增殖、迁移及血管生成能力的影响；同时探索了外泌体miR-3124-5p在体内对肿瘤生长的调控作用。

### 研究结果
本研究在胆管癌样本与对照样本中共鉴定出632个外泌体DEMs。DEMs的靶基因显著富集于p53信号通路等多条生物学通路中。miR-3124-5p在胆管癌患者血清外泌体及胆管癌细胞来源外泌体中均呈高表达；过表达miR-3124-5p可促进RBE细胞的迁移与存活能力。进一步实验显示，外泌体miR-3124-5p过表达可增强HUVECs的增殖、迁移及血管生成能力，而敲低miR-3124-5p则可产生相反的效应。机制研究表明，miR-3124-5p可靶向结合生长分化因子11（growth differentiation factor 11，GDF11）并下调其表达水平。此外，外泌体miR-3124-5p可在体内促进肿瘤生长。

### 研究结论
本研究结果证实，包裹于外泌体中的miR-3124-5p可通过靶向调控GDF11促进胆管癌的恶性进展。外泌体miR-3124-5p及GDF11有望成为胆管癌潜在的生物标志物或治疗靶点。