In this study, the functional role of miR-550a-3 and its direct target nuclear factor IC (NFIC) in esophageal squamous cell cancer (ESCC) cells were explored. Differential expression of miR-550a-3 in ESCC tissues was acquired from TCGA database, and Kaplan–Meier method was used to determine the relationship between miR-550a-3 expression and survival time of ESCC patients. Expression level of miR-550a-3 in several ESCC cell lines was measured by qRT-PCR. Two cell lines including Eca109 and JAR were used to perform proliferation, cloning, invasion and migration experiments. Targeted relationship between miR-550a-3 and NFIC was speculated by predication software and confirmed by dual luciferase assay. Additionally, potential relationship between miR-550a-3 and NFIC was analyzed by Spearman rank correlation analysis and western blot. Rescue assays were performed to explore the function of miR-550a-3/NFIC in ESCC cells biological behaviors. Expression levels of key proteins involved in epithelial-to-mesenchymal transition (EMT) process were determined by western blot. By consulting TCGA database, we found that high expression of miR-550a-3 was positively connected with the poor prognosis of patients with ESCC. In addition, overexpression of miR-550a-3 promoted the proliferation, colony formation and metastasis of ESCC cells. Moreover, rescue assays revealed that overexpression of NFIC attenuated the promoting effects of miR-550a-3 on ESCC cells malignant behaviors. While the promoting effects of miR-550a-3 on EMT process were inhibited by NFIC. Our results illustrate the importance of miR-550a-3/NFIC in regulation of ESCC cells growth and metastasis, which could contribute to developing novel target for early diagnosis or neoteric therapeutic target for ESCC.

在本研究中，探讨了 miR-550a-3 及其直接靶核因子 IC (NFIC) 在食管鳞状细胞癌 (ESCC) 细胞中的功能作用。从TCGA数据库中获取ESCC组织中miR-550a-3的差异表达，并采用Kaplan-Meier法确定miR-550a-3表达与ESCC患者生存时间的关系。通过 qRT-PCR 测量几种 ESCC 细胞系中 miR-550a-3 的表达水平。使用Eca109和JAR两种细胞系进行增殖、克隆、侵袭和迁移实验。通过预测软件推测 miR-550a-3 和 NFIC 之间的靶向关系，并通过双荧光素酶测定证实。此外，通过 Spearman 等级相关分析和蛋白质印迹分析 miR-550a-3 和 NFIC 之间的潜在关系。进行救援实验以探索 miR-550a-3/NFIC 在 ESCC 细胞生物学行为中的功能。通过蛋白质印迹测定参与上皮间质转化（EMT）过程的关键蛋白的表达水平。通过查阅TCGA数据库，我们发现miR-550a-3的高表达与ESCC患者的不良预后呈正相关。此外，miR-550a-3的过表达促进ESCC细胞的增殖、集落形成和转移。此外，救援实验表明，NFIC 的过度表达减弱了 miR-550a-3 对 ESCC 细胞恶性行为的促进作用。而miR-550a-3对EMT过程的促进作用则被NFIC抑制。我们的结果说明了 miR-550a-3/NFIC 在调节食管鳞癌细胞生长和转移中的重要性，这可能有助于开发食管鳞癌早期诊断的新靶点或近代治疗靶点。