Jing Liang, Hua Xu, Yuanna Du, Rukun Zang, Junjun Mou
Department of Gynecology, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, People's Republic of China.
Department of Obstetrics, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, Yantai, People's Republic of China.
Cancer Manag Res. 2020 Dec 31;12:13541-13552. doi: 10.2147/CMAR.S283747. eCollection 2020.
BACKGROUND/AIM: The current therapeutic strategies for endometrial cancer are limited and unsatisfactory. Accumulating evidence suggest that microRNAs (miRNAs) participate in tumor growth and metastasis. Mesenchymal stem cells (MSCs) derived exosomes (Exos) are considered as better miRNA delivery vehicles. Here, we investigated the therapeutic effect of exosomal miR-499a-5p (miR-499) in human endometrial cancer metastasis.
Microarray analysis and RT-PCR were performed to detect the relative expression of miR-499 in endometrial cancer tissues and cell lines. MSC-derived Exos were characterized by transmission electron microscope (TEM), Western blot (WB), and nanoparticle tracking analysis (NTA). miR-499 was loading into Exos using electroporation. Cell proliferation and angiogenesis capacity were tested by 5-ethynyl-29-deoxyuridine (EdU) assay and tube formation assay, respectively. Dual-luciferase reporter assay (DLR) was used to confirm the connection of miR-499 and VAV3.
We found that the expression of miR-499 was significantly downregulated in cancer tissues compared with adjacent tissues in endometrial cancer patients. Moreover, exosomal miR-499 not only dramatically suppressed endometrial cancer cells proliferation, endothelial cells tube formation in vitro, but also inhibited tumor growth and angiogenesis in vivo. In addition, we confirmed that miR-499 directly targets the 3'UTR sequence of VAV3.
The novel identified exosomal miR-499 functions as a tumor suppressor in endometrial cancer though regulating VAV3, and these findings could be a valid molecular target for endometrial cancer therapy.
背景/目的：子宫内膜癌目前的治疗策略有限且不尽人意。越来越多的证据表明，微小RNA（miRNA）参与肿瘤生长和转移。间充质干细胞（MSC）衍生的外泌体（Exos）被认为是更好的miRNA递送载体。在此，我们研究了外泌体miR-499a-5p（miR-499）对人子宫内膜癌转移的治疗作用。
进行微阵列分析和逆转录-聚合酶链反应（RT-PCR）以检测miR-499在子宫内膜癌组织和细胞系中的相对表达。通过透射电子显微镜（TEM）、蛋白质免疫印迹（WB）和纳米颗粒跟踪分析（NTA）对MSC衍生的Exos进行表征。使用电穿孔将miR-499加载到Exos中。分别通过5-乙炔基-2'-脱氧尿苷（EdU）测定法和管形成测定法测试细胞增殖和血管生成能力。采用双荧光素酶报告基因测定法（DLR）来确认miR-499与VAV3的关联。
我们发现，与子宫内膜癌患者的癌旁组织相比，miR-499在癌组织中的表达显著下调。此外，外泌体miR-499不仅在体外显著抑制子宫内膜癌细胞增殖、内皮细胞管形成，而且在体内抑制肿瘤生长和血管生成。此外，我们证实miR-499直接靶向VAV3的3'非翻译区（UTR）序列。
新鉴定的外泌体miR-499通过调节VAV3在子宫内膜癌中发挥肿瘤抑制作用，这些发现可能成为子宫内膜癌治疗的有效分子靶点。
