Restoration of mutant K-Ras repressed miR-199b inhibits K-Ras mutant non-small cell lung cancer progression
Restoration of mutant K-Ras repressed miR-199b inhibits K-Ras mutant non-small cell lung cancer progression
复制标题
恢复突变型 K-Ras 抑制的 miR-199b 可抑制 K-Ras 突变型非小细胞肺癌进展
DOI：
10.1186/s13046-019-1170-7
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发表时间：
2019-04-15
影响因子：
11.3
通讯作者：
Xu, Cheng-Xiong
中科院分区：
文献类型：
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作者：
Jin, Hua;Jang, Yoonjeong;Xu, Cheng-Xiong
研究背景miRNAs在K-Ras突变的非小细胞肺癌（NSCLC）的发生发展中起重要作用。然而，大多数研究都集中在靶向K-Ras的miRNA上。本研究以突变型K-Ras调控的miRNAs及其功能为研究对象。方法利用miRNAs芯片技术筛选突变型K-Ras调控的miRNAs。通过qRT-PCR测量miR-199 b表达水平。采用Western blot和免疫组化方法检测蛋白表达水平。通过过表达或抑制miR-199 b，在体外和体内检测miR-199 b对NSCLC的影响。DNA甲基化测定亚硫酸氢盐sequencing.ResultsAn呈负相关性K-Ras突变状态和miR-199 b水平在NSCLC标本和细胞系。抑制miR-199 b刺激NSCLC生长和转移，而恢复miR-199 b抑制K-Ras突变驱动的肺肿瘤发生以及K-Ras突变的NSCLC生长和转移。miR-199 b通过靶向K-Ras、KSR 2、PIK 3R 1、Akt 1和Rheb 1来灭活ERK和Akt通路。此外，我们确定，突变K-Ras抑制miR-199 b的表达，通过增加miR-199 b启动子methylation.ConclusionOur的研究结果表明，突变K-Ras发挥致癌作用，通过下调miR-199 b在NSCLC和miR-199 b的过表达是一种新的策略，用于治疗K-Ras突变的NSCLC。
BackgroundmiRNAs play crucial role in the progression of K-Ras-mutated nonsmall cell lung cancer (NSCLC). However, most studies have focused on miRNAs that target K-Ras. Here, we investigated miRNAs regulated by mutant K-Ras and their functions.MethodsmiRNAs regulated by mutant K-Ras were screened using miRNA arrays. miR-199b expression levels were measured by qRT-PCR. The protein expression levels were measured using Western blot and immunohistochemistry. The effects of miR-199b on NSCLC were examined both in vitro and in vivo by overexpressing or inhibiting miR-199b. DNA methylation was measured by bisulfite sequencing.ResultsAn inverse correlation was observed between K-Ras mutation status and miR-199b levels in NSCLC specimens and cell lines. The inhibition of miR-199b stimulated NSCLC growth and metastasis, while restoration of miR-199b suppressed K-Ras mutation-driven lung tumorigenesis as well as K-Ras-mutated NSCLC growth and metastasis. miR-199b inactivated ERK and Akt pathways by targeting K-Ras, KSR2, PIK3R1, Akt1, and Rheb1. Furthermore, we determined that mutant K-Ras inhibits miR-199b expression by increasing miR-199b promoter methylation.ConclusionOur findings suggest that mutant K-Ras plays an oncogenic role through downregulating miR-199b in NSCLC and that overexpression of miR-199b is a novel strategy for the treatment of K-Ras-mutated NSCLC.