Wei Ke, Pan Chunfeng, Yao Guoliang, Liu Bin, Ma Teng, Xia Yang, Jiang Wei, Chen Liang, Chen Yijiang
Department of Thoracic and Cardiovascular Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
Department of Cardiothotacic Surgery, The First People's Hospital of Changzhou, The Third Affiliated Hospital of Soochow University, Changzhou, China.
Cell Physiol Biochem. 2017;44(4):1545-1558. doi: 10.1159/000485650. Epub 2017 Dec 4.
BACKGROUND/AIMS: MicroRNAs have been validated to play a crucial role in tumorigenesis of non-small cell lung cancer (NSCLC). Although miR-106b-5p has been reported to play a vital role in various malignancies the physiological function of miR-106b-5p in NSCLC still remain unknown. In this study, we investigated the role of miR-106b-5p in NSCLC.
Quantitative real-time polymerase chain reaction was conducted to estimate the expression of miR-106b-5p and BTG3 in both NSCLC tissues and cell lines. The effects of miR-106b-5p on proliferation were determined in vitro using CCK-8 proliferation assays, 5-ethynyl-2'-deoxyuridine (EdU) incorporation, colony formation assays and cell-cycle assays and the in vivo effects were evaluated by a mouse tumorigenicity model. Cell apoptosis and cell cycle was investigated by flow cytometric analysis in vitro. The molecular mechanism underlying the relevance between miR-106b-5p and BTG3 was confirmed by luciferase assay and western blot.
In current study, we found a relatively higher miR-106b-5p and lower BTG3 expression in NSCLC specimens and cell lines. BTG3 was verified as a direct target of miR-106b-5p by luciferase assay. In vitro, over-expression of miR-106b-5p promoted proliferation and inhibited apoptosis by down-regulating BTG3 expression. In vivo, miR-106b-5p promoted xenograft tumor formation.
Our findings revealed for the first time that miR-106b-5p plays a tumorigenesis role in NSCLC progression by down-regulating BTG3 expression, which may lead to a novel insight to the potential biomarker and novel therapeutic strategies for NSCLC patients.
背景/目的：微小RNA已被证实非小细胞肺癌（NSCLC）的肿瘤发生中起关键作用。尽管已有报道称miR-106b-5p在多种恶性肿瘤中发挥重要作用，但miR-106b-5p在NSCLC中的生理功能仍不清楚。在本研究中，我们调查了miR-106b-5p在NSCLC中的作用。
采用定量实时聚合酶链反应来评估NSCLC组织和细胞系中miR-106b-5p和BTG3的表达。使用CCK-8增殖试验、5-乙炔基-2'-脱氧尿苷（EdU）掺入、集落形成试验和细胞周期试验在体外确定miR-106b-5p对增殖的影响，并通过小鼠致瘤模型评估体内影响。通过体外流式细胞术分析研究细胞凋亡和细胞周期。通过荧光素酶试验和蛋白质印迹法证实miR-106b-5p与BTG3相关性的分子机制。
在本研究中，我们发现NSCLC标本和细胞系中miR-106b-5p表达相对较高，而BTG3表达较低。荧光素酶试验证实BTG3是miR-106b-5p的直接靶点。在体外，miR-106b-5p的过表达通过下调BTG3表达促进增殖并抑制凋亡。在体内，miR-106b-5p促进异种移植瘤形成。
我们的研究结果首次揭示miR-106b-5p通过下调BTG3表达在NSCLC进展中发挥肿瘤发生作用，这可能为NSCLC患者的潜在生物标志物和新治疗策略提供新的见解。
