Overexpression of miR-199a-5p decreases esophageal cancer cell proliferation through repression of mitogen-activated protein kinase kinase kinase-11 (MAP3K11).
Overexpression of miR-199a-5p decreases esophageal cancer cell proliferation through repression of mitogen-activated protein kinase kinase kinase-11 (MAP3K11).
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DOI：
10.18632/oncotarget.6752
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发表时间：
2016-02-23
期刊：
影响因子：
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通讯作者：
Donahue JM
中科院分区：
文献类型：
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作者：
Byrnes KA;Phatak P;Mansour D;Xiao L;Zou T;Rao JN;Turner DJ;Wang JY;Donahue JM
研究癌细胞中失调的microRNAs （miRs）的致癌或抑瘤功能也可能发现新的miR靶点，这些靶点本身可以作为治疗靶点。通过阵列分析，我们之前已经确定，与食管上皮细胞相比，miR-199a-5p是两种食管癌细胞系中下调最多的miR。预测MiR-199a-5p以高亲和力结合丝裂原活化蛋白激酶激酶激酶11 (MAP3K11) mRNA。在本研究中，我们观察到MAP3K11在食管癌细胞系中明显过表达。在这些细胞中被迫表达miR-199a-5p导致MAP3K11 mRNA和蛋白水平下降，这是由于MAP3K11 mRNA稳定性下降。miR-199a-5p与MAP3K11 mRNA之间的直接结合相互作用通过生物素下拉试验和异种荧光素酶报告基因构建得到证实，并通过突变分析得到证实。最后，强迫表达miR-199a-5p通过诱导G2/M阻滞来降低食管癌细胞的增殖。这种作用部分是由map3k11介导的c-Jun磷酸化减少导致cyclin D1转录减少介导的。这些发现表明，miR-199a-5p在食管癌细胞中作为肿瘤抑制因子，其下调通过靶向MAP3K11促进细胞增殖。
Studies examining the oncogenic or tumor suppressive functions of dysregulated microRNAs (miRs) in cancer cells may also identify novel miR targets, which can themselves serve as therapeutic targets. Using array analysis, we have previously determined that miR-199a-5p was the most downregulated miR in two esophageal cancer cell lines compared to esophageal epithelial cells. MiR-199a-5p is predicted to bind mitogen-activated protein kinase kinase kinase 11 (MAP3K11) mRNA with high affinity. In this study, we observed that MAP3K11 is markedly overexpressed in esophageal cancer cell lines. Forced expression of miR-199a-5p in these cells leads to a decrease in the mRNA and protein levels of MAP3K11, due to decreased MAP3K11 mRNA stability. A direct binding interaction between miR-199a-5p and MAP3K11 mRNA is demonstrated using biotin pull-down assays and heterologous luciferase reporter constructs and confirmed by mutational analysis. Finally, forced expression of miR-199a-5p decreases proliferation of esophageal cancer cells by inducing G2/M arrest. This effect is mediated, in part, by decreased transcription of cyclin D1, due to reduced MAP3K11-mediated phosphorylation of c-Jun. These findings suggest that miR-199a-5p acts as a tumor suppressor in esophageal cancer cells and that its downregulation contributes to enhanced cellular proliferation by targeting MAP3K11.