Department of Pathology and Key Laboratories for Xinjiang Endemic and Ethnic Diseases, Shihezi University School of Medicine, Shihezi, Xinjiang, China.
Department of Biomedical Sciences and Cornell Stem Cell Program, Cornell University, Ithaca, NY, USA.
J Exp Clin Cancer Res. 2017 Dec 13;36(1):182. doi: 10.1186/s13046-017-0658-2.
Novel therapies tailored to the molecular composition of esophageal squamous cell carcinoma (ESCC) are needed to improve patient survival. We investigated the regulatory network of long intergenic non-protein coding RNA, regulator of reprogramming (linc-ROR) and sex-determining region Y-box 9 (SOX9), and their therapeutic relevance in ESCC.
Linc-ROR and SOX9 expression were examined in ESCC specimens, cell lines, and cultured tumorspheres. We investigated the effects of linc-ROR on SOX9 expression and malignant phenotypes by CCK8, colony formation, Transwell, and sphere-forming assay. The linc-ROR/SOX9 interaction mediated by multiple microRNAs (miRNAs) was confirmed by bioinformatic analysis, luciferase assay, and RNA-binding protein immunoprecipitation, transient overexpression or antagonizing endogenous candidate miRNAs. The effect of linc-ROR depletion on tumor growth was assessed by xenograft assay.
A positive correlation between linc-ROR and SOX9 expression was found in clinical ESCC specimens (r = 0.562, P = 0.036), cell lines, and tumorspheres. Silencing of linc-ROR significantly inhibited cell proliferation, motility, chemoresistance, and self-renewal capacity. Mechanistically, linc-ROR modulating the derepression of SOX9 by directly sponging multiple miRNAs including miR-15b, miR-33a, miR-129, miR-145, and miR-206. Antagonizing these miRNAs counteracted with linc-ROR silencing, whereas the repression of SOX9 abrogated malignant phenotypes induced by the cocktail of miRNA inhibitors. Moreover, linc-ROR disruption was sufficient to attenuate tumor growth and cancer stem cell marker expression in vivo.
Our results demonstrate that the linc-ROR-miRNA-SOX9 regulatory network may represent a novel therapeutic target for ESCC.
需要针对食管鳞状细胞癌（ESCC）的分子组成量身定制新型疗法，以提高患者生存率。我们研究了长链非编码 RNA、调节重编程的 regulator（linc-ROR）和性别决定区 Y 盒 9（SOX9）的调控网络及其在 ESCC 中的治疗相关性。
在 ESCC 标本、细胞系和培养的肿瘤球中检测 linc-ROR 和 SOX9 的表达。我们通过 CCK8、集落形成、Transwell 和球体形成测定法研究了 linc-ROR 对 SOX9 表达和恶性表型的影响。通过生物信息学分析、荧光素酶测定和 RNA 结合蛋白免疫沉淀、瞬时过表达或拮抗内源性候选 miRNA 证实了 linc-ROR/SOX9 相互作用。通过异种移植测定评估 linc-ROR 耗竭对肿瘤生长的影响。
在临床 ESCC 标本（r=0.562，P=0.036）、细胞系和肿瘤球中发现 linc-ROR 和 SOX9 表达呈正相关。沉默 linc-ROR 显著抑制细胞增殖、迁移、化学抗性和自我更新能力。在机制上，linc-ROR 通过直接海绵吸附多种 miRNA（包括 miR-15b、miR-33a、miR-129、miR-145 和 miR-206）来调节 SOX9 的去抑制。拮抗这些 miRNA 可以抵消 linc-ROR 沉默的作用，而 SOX9 的抑制则消除了 miRNA 抑制剂混合物诱导的恶性表型。此外，linc-ROR 破坏足以在体内减弱肿瘤生长和癌症干细胞标志物表达。
我们的结果表明，linc-ROR-miRNA-SOX9 调控网络可能代表 ESCC 的一种新的治疗靶点。
