Li Rong, Deng Yinan, Liang Jinliang, Hu Zhongying, Li Xuejiao, Liu Huanyi, Wang Guoying, Fu Binsheng, Zhang Tong, Zhang Qi, Yang Yang, Chen Guihua, Liu Wei
Guangdong Provincial Key Laboratory of Liver Disease Research, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510630, China.
Organ Transplantation Research Center of Guangdong Province, Guangdong province engineering laboratory for transplantation medicine, Guangzhou, 510630, China.
Cell Oncol (Dordr). 2021 Apr;44(2):279-295. doi: 10.1007/s13402-020-00564-y. Epub 2020 Oct 9.
Multiple circular RNAs (circRNAs) have been reported to be dysregulated in hepatocellular carcinoma (HCC). However, their functions and modes of action are still largely unclear. Identifying key circRNAs and revealing their potential functions and molecular mechanisms is considered important for improving the diagnosis and treatment of HCC.
Dysregulated circRNAs in HCC were identified through integration of three human HCC circRNAs microarray datasets (GSE94508, GSE97332 and GSE 78520), followed by qRT-PCR validation in primary HCC tissues and cell lines. circRNA characteristics were verified through Sanger sequencing, RNase R treatment, northern blotting and intracellular localization analyses. In addition, circRNA functions in HCC development were assessed using CCK8, colony formation, EDU incorporation, flow cytometry, transwell and scratch wound healing assays in vitro and tumor xenograft assays in vivo. Next, underlying molecular mechanisms in HCC were assessed using dual-luciferase reporter, RNA pull-down, RNA immunoprecipitation and western blotting assays.
We found that a novel circular RNA, circ-102,166, was down-regulated in HCC and that its expression level was significantly associated with multiple clinicopathologic characteristics, as well as the clinical prognosis of HCC patients. In vitro and in vivo experiments revealed that circ-102,166 overexpression significantly inhibited the proliferation, invasion, migration and tumorigenicity of HCC cells. Furthermore, we found that circ-102,166 can bind to miR-182 and miR-184 to regulate the expression of several of their downstream targets (FOXO3a, MTSS1, SOX7, p-RB and c-MYC).
Our data revealed a tumor-suppressing role of circ-102,166 in HCC. Down-regulation of circ-102,166 enhanced the proliferation and invasion of HCC cells by releasing the oncomiRs miR-182 and miR-184.
已有报道称多种环状RNA（circRNA）在肝细胞癌（HCC）中表达失调。然而，它们的功能和作用模式仍不清楚。识别关键的circRNA并揭示其潜在功能和分子机制被认为对改善HCC的诊断和治疗具有重要意义。
通过整合三个人类HCC circRNA微阵列数据集（GSE94508、GSE97332和GSE 78520）鉴定HCC中失调的circRNA，随后在原发性HCC组织和细胞系中进行qRT-PCR验证。通过Sanger测序、RNase R处理、Northern印迹和细胞内定位分析验证circRNA特征。此外，使用CCK8、集落形成、EDU掺入、流式细胞术、Transwell和划痕伤口愈合试验在体外评估circRNA在HCC发展中的功能，并在体内进行肿瘤异种移植试验。接下来，使用双荧光素酶报告基因、RNA下拉、RNA免疫沉淀和蛋白质印迹试验评估HCC中的潜在分子机制。
我们发现一种新的环状RNA，circ-102,166，在HCC中下调，其表达水平与多种临床病理特征以及HCC患者的临床预后显著相关。体外和体内实验表明，circ-102,166过表达显著抑制HCC细胞的增殖、侵袭、迁移和致瘤性。此外，我们发现circ-102,166可以与miR-182和miR-184结合，以调节其几个下游靶点（FOXO3a、MTSS1、SOX7、p-RB和c-MYC）的表达。
我们的数据揭示了circ-102,166在HCC中的肿瘤抑制作用。circ-102,166的下调通过释放致癌miR-182和miR-184增强了HCC细胞的增殖和侵袭。
