Liu Jie, Xu Haiyan, Wang Nan, Sun Mingyan
Department of Thoracic Surgery, Shandong Institute of Tumor Control, Shandong Cancer Hospital, Shandong First Medical University, Shandong Academy of Medical Sciences, Jinan, Shandong 250000, P.R. China.
The Second Department of Operating Room, Binzhou People's Hospital, Binzhou, Shandong 256610, P.R. China.
Exp Ther Med. 2020 Dec;20(6):222. doi: 10.3892/etm.2020.9352. Epub 2020 Oct 15.
MicroRNA (miR)-15b is an important regulator in several types of cancer, such as gastric cancer, colorectal cancer and oesophageal squamous cell carcinoma. The PI3K/AKT signalling pathway has been implicated in the growth and metastasis of oesophageal cancer (EC). The aim of the present study was to investigate the biological effects of miR-15b in EC, as well as the underlying mechanism involving the PI3K/AKT signalling pathway. The present study included 74 patients with EC and 74 healthy volunteers. The expression of miR-15b in peripheral blood mononuclear cells (PBMCs) and EC cell lines was evaluated via reverse transcription-quantitative PCR. The receiver operating characteristic curve was plotted to determine the diagnostic significance of miR-15b. EC cell viability, apoptosis, migration and invasion were analysed by conducting MTT, flow cytometry and transwell assays, respectively. Protein expression levels were analysed via western blotting. The results indicated that PBMCs isolated from patients with EC had lower miR-15b expression levels compared with PBMCs isolated from healthy volunteers. In patients with EC, miR-15b expression was strongly associated with tumour size, lymph node metastasis, TNM stage, fibrous membrane invasion and histologic grade. The results of the gain/loss-of-function experiments indicated that miR-15b inhibited EC cell viability, migration and invasion, facilitated EC cell apoptosis and attenuated the PI3K/AKT signalling pathway in EC109 and TE10 cells. Treatment of EC cells with the PI3K/AKT pathway agonist recilisib displayed the opposite effects, blocking the inhibitory function of miR-15b mimic on EC cell viability, migration and invasion. In summary, the results indicated that miR-15b suppressed EC cell viability, migration and invasion, and promoted EC cell apoptosis by inhibiting the PI3K/AKT signalling pathway.
微小RNA（miR）-15b是多种癌症的重要调节因子，如胃癌、结直肠癌和食管鳞状细胞癌。PI3K/AKT信号通路与食管癌（EC）的生长和转移有关。本研究的目的是探讨miR-15b在EC中的生物学作用，以及涉及PI3K/AKT信号通路的潜在机制。本研究纳入了74例EC患者和74名健康志愿者。通过逆转录定量PCR评估外周血单个核细胞（PBMC）和EC细胞系中miR-15b的表达。绘制受试者工作特征曲线以确定miR-15b的诊断意义。分别通过MTT、流式细胞术和Transwell实验分析EC细胞活力、凋亡、迁移和侵袭。通过蛋白质印迹分析蛋白质表达水平。结果表明，与从健康志愿者中分离的PBMC相比，从EC患者中分离的PBMC具有较低的miR-15b表达水平。在EC患者中，miR-15b表达与肿瘤大小、淋巴结转移、TNM分期、纤维膜侵犯和组织学分级密切相关。功能获得/丧失实验结果表明，miR-15b抑制EC109和TE10细胞的活力、迁移和侵袭，促进EC细胞凋亡，并减弱PI3K/AKT信号通路。用PI3K/AKT通路激动剂瑞西利昔治疗EC细胞显示出相反的效果，阻断了miR-15b模拟物对EC细胞活力、迁移和侵袭的抑制作用。总之，结果表明miR-15b通过抑制PI3K/AKT信号通路抑制EC细胞活力、迁移和侵袭，并促进EC细胞凋亡。
