Department of Otorhinolaryngology, Head and Neck Surgery, The Second Affiliated Hospital, Harbin Medical University, No. 148 Baojian Road, Nangang District, Harbin 150086, China.
Department of Otorhinolaryngology, Head and Neck Surgery, The Second Affiliated Hospital, Harbin Medical University, No. 148 Baojian Road, Nangang District, Harbin 150086, China
Clin Sci (Lond). 2019 May 9;133(9):1053-1066. doi: 10.1042/CS20190110. Print 2019 May 15.
Circular RNAs (circRNAs) are a class of non-coding RNAs (ncRNAs) broadly expressed in cells of various species. However, the molecular mechanisms that link circRNAs with laryngeal squamous cell carcinoma (LSCC) are not well understood. In the present study, we attempted to provide novel basis for targeted therapy for LSCC from the aspect of circRNA-microRNA (miRNA)-mRNA interaction. We investigated the expression of circRNAs in three paired LSCC tissues and adjacent non-tumor tissues by microarray analysis. Differentially expressed circRNAs were identified between LSCC tissues and non-cancerous matched tissues, including 527 up-regulated circRNAs and 414 down-regulated circRNAs. We focused on hsa_circ_0059354, which is located on chromosome 20 and derived from RASSF2, and thus we named it circRASSF2. circRASSF2 was found to be significantly up-regulated in LSCC tissues and LSCC cell lines compared with paired adjacent non-tumorous tissues and normal cells. Moreover, knockdown of circRASSF2 significantly inhibited cell proliferation and migration , which was blocked by miR-302b-3p inhibitor. Bioinformatics analysis predicted that there is a circRASSF2/miR-302b-3p/ insulin-like growth factor 1 receptor (IGF-1R) axis in LSCC progression. Dual-luciferase reporter system validated the direct interaction of circRASSF2, miR-302b-3p, and IGF-1R. Western blot verified that inhibition of circRASSF2 decreased IGF-1R expression. Furthermore, silencing circRASSF2 suppressed LSCC growth Importantly, we demonstrated that circRASSF2 was up-regulated in serum exosomes from LSCC patients. Altogether, silencing circRASSF2 suppresses progression of LSCC by interacting with miR-302b-3p and decreasing inhibiting IGF-1R expression. In conclusion, these data suggest that circRASSF2 is a central component linking circRNAs to progression of LSCC via an miR-302b-3p/IGF-1R axis.
环状 RNA（circRNAs）是一类在各种物种的细胞中广泛表达的非编码 RNA（ncRNAs）。然而，circRNAs 与喉鳞状细胞癌（LSCC）之间的分子机制尚不清楚。在本研究中，我们试图从 circRNA-miRNA（miRNA）-mRNA 相互作用的角度为 LSCC 的靶向治疗提供新的依据。我们通过微阵列分析研究了三对 LSCC 组织和相邻非肿瘤组织中 circRNAs 的表达。在 LSCC 组织与非癌匹配组织之间鉴定出差异表达的 circRNAs，包括 527 个上调的 circRNAs 和 414 个下调的 circRNAs。我们关注位于 20 号染色体上并源自 RASSF2 的 hsa_circ_0059354，因此将其命名为 circRASSF2。与配对的相邻非肿瘤组织和正常细胞相比，circRASSF2 在 LSCC 组织和 LSCC 细胞系中显著上调。此外，circRASSF2 的敲低显著抑制了细胞增殖和迁移，这被 miR-302b-3p 抑制剂阻断。生物信息学分析预测，在 LSCC 进展过程中有一个 circRASSF2/miR-302b-3p/胰岛素样生长因子 1 受体（IGF-1R）轴。双荧光素酶报告系统验证了 circRASSF2、miR-302b-3p 和 IGF-1R 之间的直接相互作用。Western blot 验证了抑制 circRASSF2 降低了 IGF-1R 的表达。此外，沉默 circRASSF2 抑制了 LSCC 的生长。重要的是，我们证明了 LSCC 患者血清外泌体中 circRASSF2 的上调。总之，沉默 circRASSF2 通过与 miR-302b-3p 相互作用并降低抑制 IGF-1R 的表达来抑制 LSCC 的进展。综上所述，这些数据表明 circRASSF2 是连接 circRNAs 与 LSCC 进展的核心组成部分，通过 miR-302b-3p/IGF-1R 轴。
