Department of Infection Disease (No.3), Second Affiliated Hospital of Harbin Medical University, China.
Department of Respiratory Oncology, Harbin Medical University Cancer Hospital, China.
Pathol Res Pract. 2023 May;245:154435. doi: 10.1016/j.prp.2023.154435. Epub 2023 Apr 5.
Circular RNA RNA-binding motif protein 23 (circ_RBM23; ID: hsa_circ_0000524) is a novel regulator in hepatocellular carcinoma (HCC). Herein, we planned to investigate its role in sorafenib resistance in HCC.
Levels of circ_RBM23, microRNA (miR)-338-3p, Ras-related GTPase-trafficking protein (RAB1B), Snail and E-cadherin were detected by real-time quantitative PCR and western blotting. Sorafenib resistant (SR) HCC cells (Huh7/SR and SK-HEP-1/SR) were established by acquisition of sorafenib resistance, and cell functions were measured by MTT assay, Edu assay, colony formation assay, apoptosis assay, transwell assay, and in vivo xenograft formation assay. Crosslink between miR-338-3p and circ_RBM23 or RAB1B was confirmed by bioinformatics analysis and dual-luciferase reporter assay.
Circ_RBM23 upregulation was discovered in the tissues of SR patients and SR cells, which was accompanied with miR-338-3p downregulation and RAB1B upregulation. The 50% inhibitory concentration (IC) of sorafenib in SR cells was greatly suppressed by interfering circ_RBM23 or reinforcing miR-338-3p, allied with this was the inhibition of EdU-positive cell rate, colony formation and migration/invasion abilities under sorafenib treatment, as well as the enhancement of apoptotic rate. Moreover, circ_RBM23 inhibition delayed tumor growth of Huh7/SR cells under sorfanib treatment in vivo.
Circ_RBM23 promoted chemoresistance, malignant proliferation, migration and invasion of SR HCC cells by modulating miR-338-3p/RAB1B axis.
环状 RNA RNA 结合基序蛋白 23（circ_RBM23；ID：hsa_circ_0000524）是肝细胞癌（HCC）的一种新型调节因子。在此，我们计划研究其在 HCC 索拉非尼耐药中的作用。
通过实时定量 PCR 和 Western blot 检测 circ_RBM23、微小 RNA（miR）-338-3p、Ras 相关 GTP 结合蛋白（RAB1B）、Snail 和 E-钙黏蛋白的水平。通过获得索拉非尼耐药，建立索拉非尼耐药（SR）HCC 细胞（Huh7/SR 和 SK-HEP-1/SR），并通过 MTT 测定、Edu 测定、集落形成测定、凋亡测定、transwell 测定和体内异种移植形成测定来测量细胞功能。通过生物信息学分析和双荧光素酶报告基因测定证实 miR-338-3p 与 circ_RBM23 或 RAB1B 之间的交联。
在 SR 患者和 SR 细胞的组织中发现 circ_RBM23 上调，同时伴有 miR-338-3p 下调和 RAB1B 上调。干扰 circ_RBM23 或增强 miR-338-3p 可显著抑制 SR 细胞的索拉非尼半数抑制浓度（IC），同时抑制索拉非尼处理下 EdU 阳性细胞率、集落形成和迁移/侵袭能力的增强，以及凋亡率的增强。此外，circ_RBM23 抑制可在体内索拉非尼治疗下延迟 Huh7/SR 细胞的肿瘤生长。
circ_RBM23 通过调节 miR-338-3p/RAB1B 轴促进 SR HCC 细胞的化疗耐药性、恶性增殖、迁移和侵袭。
