Circular RNA circRHOBTB3 has been characterized as a tumor suppressor in gastric cancer, while its role in hepatocellular carcinoma (HCC) is unknown. This study was carried out to analyze the role of circRHOBTB3 in HCC. In this study, circRHOBTB3, mature miR-18a, and miR-18a precursor in HCC and paired non-cancer tissues were detected by RT-qPCR. The role of circRHOBTB3 in the production of mature miR-18a was explored by transfecting circRHOBTB3 expression vector into HCC cells, followed by RT-qPCR to determine the expression of mature miR-18a and miR-18a precursor. The role of circRHOBTB3 and miR-18a in HCC cell proliferation was studied using CCK-8 assay. CircRHOBTB3 was under-expressed in HCC compared to normal tissues. In HCC cells, circRHOBTB3 overexpression decreased mature miR-18a level but not miR-18a precursor. Cell proliferation analysis showed that circRHOBTB3 overexpression decreased cell proliferation while miR-18a overexpression increased cell proliferation. Moreover, circRHOBTB3 suppressed the role of miR-18a in cell proliferation. CircRHOBTB3 is downregulated in HCC and may suppress cell proliferation by reducing miR-18a production.

中文翻译：

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环状RNA circRHOBTB3在肝细胞癌中下调并通过抑制miR-18a成熟来抑制细胞增殖

环状 RNA circRHOBTB3 已被表征为胃癌中的肿瘤抑制因子，而其在肝细胞癌 (HCC) 中的作用尚不清楚。本研究旨在分析 circRHOBTB3 在 HCC 中的作用。在本研究中，通过 RT-qPCR 检测了 HCC 和配对非癌组织中的 circRHOBTB3、成熟的 miR-18a 和 miR-18a 前体。通过将circRHOBTB3表达载体转染到HCC细胞中，然后通过RT-qPCR确定成熟miR-18a和miR-18a前体的表达来探索circRHOBTB3在成熟miR-18a产生中的作用。使用CCK-8测定研究circRHOBTB3和miR-18a在HCC细胞增殖中的作用。与正常组织相比，CircRHOBTB3 在 HCC 中表达不足。在 HCC 细胞中，circRHOBTB3 过表达会降低成熟的 miR-18a 水平，但不会降低 miR-18a 前体。细胞增殖分析显示circRHOBTB3过表达降低细胞增殖而miR-18a过表达增加细胞增殖。此外，circRHOBTB3 抑制了 miR-18a 在细胞增殖中的作用。CircRHOBTB3 在 HCC 中下调，可能通过减少 miR-18a 的产生来抑制细胞增殖。