Department of Gynecology.
Disinfection Supply Center, Qinghai Red Cross Hospital, Xining, Qinghai, China.
Anticancer Drugs. 2021 Jun 1;32(5):496-507. doi: 10.1097/CAD.0000000000001058.
Circular RNAs (circRNAs) have emerged as vital regulators in the chemoresistance of diverse human tumors, including ovarian cancer. In the present study, we attempted to explore the function of circ_CELSR1 in paclitaxel resistance of ovarian cancer. Quantitative real-time PCR (qRT-PCR) was conducted for the expression of circ_CELSR1, miR-149-5p and salt inducible kinase 2 (SIK2). Cell Counting Kit-8 (CCK-8) assay was performed to evaluate the half-maximal inhibitory concentration (IC50) of paclitaxel and cell viability. Colony formation assay was adopted for cell colony formation. Flow cytometry analysis was conducted to analyze cell cycle process and apoptosis. Western blot assay was utilized to determine the protein levels. RNA immunoprecipitation (RIP) and dual-luciferase reporter assays were conducted to verify the association between miR-149-5p and circ_CELSR1 or SIK2. Murine xenograft model assay was carried out to determine the effect of circ_CELSR1 in paclitaxel resistance in vivo. Circ_CELSR1 was upregulated in paclitaxel-resistant ovarian cancer tissues and cells. Circ_CELSR1 knockdown enhanced paclitaxel sensitivity and cell apoptosis and repressed cell viability, colony formation and cell cycle process in paclitaxel-resistant ovarian cancer cells. For mechanism analysis, circ_CELSR1 could positively modulate SIK2 expression via sponging miR-149-5p. MiR-149-5p inhibition effectively restored the impacts of circ_CELSR1 knockdown on paclitaxel resistance and cell progression in paclitaxel-resistant ovarian cancer cells. MiR-149-5p overexpression suppressed paclitaxel resistance and cell progression in paclitaxel-resistant ovarian cancer cells by interacting with SIK2. In addition, circ_CELSR1 silencing impeded paclitaxel resistance of ovarian cancer in vivo. Circ_CELSR1 improved the resistance of ovarian cancer to paclitaxel by regulating miR-149-5p/SIK2 axis.
环状 RNA（circRNAs）已成为多种人类肿瘤包括卵巢癌化疗耐药性的重要调节因子。在本研究中，我们试图探讨 circ_CELSR1 在卵巢癌紫杉醇耐药中的作用。采用定量实时 PCR（qRT-PCR）检测 circ_CELSR1、miR-149-5p 和盐诱导激酶 2（SIK2）的表达。采用细胞计数试剂盒-8（CCK-8）法检测紫杉醇的半数最大抑制浓度（IC50）和细胞活力。采用集落形成实验检测细胞集落形成。采用流式细胞术分析细胞周期进程和细胞凋亡。采用 Western blot 法检测蛋白水平。采用 RNA 免疫沉淀（RIP）和双荧光素酶报告基因实验验证 miR-149-5p 与 circ_CELSR1 或 SIK2 的关系。采用小鼠异种移植模型实验检测 circ_CELSR1 在体内对紫杉醇耐药的影响。紫杉醇耐药的卵巢癌组织和细胞中 circ_CELSR1 上调。circ_CELSR1 敲低增强了紫杉醇的敏感性和细胞凋亡，抑制了紫杉醇耐药卵巢癌细胞的活力、集落形成和细胞周期进程。机制分析表明，circ_CELSR1 通过海绵吸附 miR-149-5p 正向调节 SIK2 的表达。miR-149-5p 抑制有效恢复了 circ_CELSR1 敲低对紫杉醇耐药和紫杉醇耐药卵巢癌细胞进展的影响。miR-149-5p 过表达通过与 SIK2 相互作用抑制紫杉醇耐药卵巢癌细胞的耐药性和进展。此外，circ_CELSR1 沉默抑制了卵巢癌在体内的耐药性。circ_CELSR1 通过调节 miR-149-5p/SIK2 轴提高了卵巢癌对紫杉醇的耐药性。
