Long non-coding RNA TTN-AS1/microRNA-199a-3p/runt-related transcription factor 1 gene axis regulates the progression of oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) has a high degree of malignancy, which affects the quality of life and prognosis of patients with OSCC. Our study aimed to reveal the function of long non-coding RNA TTN-AS1/microRNA-199a-3p (miR-199a-3p)/runt-related transcription factor 1 (RUNX1) axis in OSCC progression, thereby providing a novel OSCC effective strategy. Real-time quantitative polymerase chain reaction and western blotting were performed to detect the expression of TTN-AS1, miR-199a-3p, and RUNX1 in OSCC. Several cell functional experiments, including Cell Counting Kit-8, flow cytometry, and cell adhesion assays, were used to assess cell proliferation, apoptosis, adhesion, and migration. A luciferase assay was performed to confirm the interaction between TTN-AS1, miR-199a-3p, and RUNX1. Our results revealed that TTN-AS1 and RUNX1 were upregulated in OSCC tissues and cells, whereas miR-199a-3p expression was downregulated. Knockdown of TTN-AS1 or RUNX1 suppressed cell proliferation, adhesion, and migration but induced apoptosis. Additionally, miR-199a-3p inhibitor partly relieved the effects of silencing TTN-AS1 and RUNX1 in OSCC cells due to their targeting relationship. In conclusion, TTN-AS1 and RUNX1 could promote OSCC progression and miR-199a-3p partly relieved the effects of TTN-AS1 and RUNX1.

口腔鳞状细胞癌（Oral squamous cell carcinoma, OSCC）恶性程度极高，严重影响患者的生存质量与预后。本研究旨在阐明长链非编码RNA（long non-coding RNA）TTN-AS1/微小RNA-199a-3p（microRNA-199a-3p, miR-199a-3p）/runt相关转录因子1（runt-related transcription factor 1, RUNX1）调控轴在口腔鳞状细胞癌进展中的生物学功能，以期为口腔鳞状细胞癌的临床治疗提供全新有效策略。
本研究采用实时定量聚合酶链反应与蛋白质印迹法，检测口腔鳞状细胞癌组织及细胞中TTN-AS1、miR-199a-3p与RUNX1的表达水平；通过细胞计数试剂盒-8（Cell Counting Kit-8, CCK-8）实验、流式细胞术（flow cytometry）、细胞黏附实验等多项细胞功能实验，评估细胞的增殖、凋亡、黏附与迁移能力；借助荧光素酶实验（luciferase assay）验证TTN-AS1、miR-199a-3p与RUNX1之间的相互作用关系。
研究结果显示，TTN-AS1与RUNX1在口腔鳞状细胞癌组织及细胞中均呈高表达状态，而miR-199a-3p的表达水平显著下调。敲低TTN-AS1或RUNX1可抑制口腔鳞状细胞癌细胞的增殖、黏附与迁移能力，并诱导细胞凋亡。此外，miR-199a-3p抑制剂可部分逆转敲低TTN-AS1或RUNX1对口腔鳞状细胞癌细胞产生的上述生物学效应，这与三者之间的靶向调控关系一致。
综上，TTN-AS1与RUNX1可促进口腔鳞状细胞癌的进展，而miR-199a-3p可部分拮抗TTN-AS1与RUNX1的促癌作用。