MicroRNA-296-5p Promotes Invasiveness through Downregulation of Nerve Growth Factor Receptor and Caspase-8.
MicroRNA-296-5p Promotes Invasiveness through Downregulation of Nerve Growth Factor Receptor and Caspase-8.
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DOI：
10.14348/molcells.2017.2270
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发表时间：
2017-04
影响因子：
3.8
通讯作者：
Kim HH
中科院分区：
文献类型：
--
作者：
Lee H;Shin CH;Kim HR;Choi KH;Kim HH
胶质母细胞瘤(GBM)是一种难治性肿瘤，其侵袭性是其复发的主要原因之一。MicroRNAs通过种子序列与靶mRNAs的3‘端非编码区相互作用，对靶基因进行转录后调控。我们先前报道miR-296-3p受神经纤维瘤病2(NF2)调控，并通过SOCS2/STAT3增强GBM细胞的侵袭力。在本研究中，我们研究了与miR-296-3p起源于相同前体miRNA的miR-296-5p是否可以增加GBM细胞的侵袭力。观察到miR-296-5p可增强LN229、T98G、U87 MG等多种GBM细胞的侵袭能力。通过生物信息学方法，确定了两个基因为miR-296-5p靶点：caspase-8(CASP8)和神经生长因子受体(NGFR)。从Ago2免疫沉淀和荧光素酶检测的结果中，我们发现miR-296-5p通过miRNA的种子序列与靶mRNA的3‘UTR区直接相互作用而下调CASP8和NGFR。下调CASP8或NGFR也可增强GBM细胞的侵袭能力，提示CASP8和NGFR参与了miR-296-5p对GBM细胞侵袭能力的增强。与我们的发现一致，脑转移肺癌细胞中CASP8的表达下调，与亲本细胞相比，miR-296-5p的水平较高，这表明miR-296-5p可能普遍与侵袭性的获得有关。总而言之，我们的结果表明miR-296-5p是癌症侵袭性的潜在原因，并建议它作为GBM的一个有前途的治疗靶点。
Glioblastomas (GBM) are very difficult to treat and their aggressiveness is one of the main reasons for this as well as for the frequent recurrences. MicroRNAs post-transcriptionally regulate their target genes through interaction between their seed sequence and 3′UTR of the target mRNAs. We previously reported that miR-296-3p is regulated by neurofibromatosis 2 (NF2) and enhances the invasiveness of GBM cells via SOCS2/STAT3. In this study, we investigated whether miR-296-5p, which originates from the same precursor miRNA as miR-296-3p, can increase the invasiveness of GBM cells. It was observed that miR-296-5p potentiated the invasion of various GBM cells including LN229, T98G, and U87MG. Through bioinformatics approaches, two genes were identified as miR-296-5p targets: caspase-8 (CASP8) and nerve growth factor receptor (NGFR). From results obtained from Ago2 immunoprecipitation and luciferase assays, we found that miR-296-5p downregulates CASP8 and NGFR through direct interaction between seed sequence of the miRNA and 3′UTR of the target mRNA. Knockdown of CASP8 or NGFR also increased the invasive ability of GBM cells, indicating that CASP8 and NGFR are involved in potentiation of invasiveness by miR-296-5p. Consistent with our findings, CASP8 was downregulated in brain metastatic lung cancer cells, which have a high level of miR-296-5p, compared to parental cells, suggesting that miR-296-5p may be generally associated with the acquisition of invasiveness. Collectively, our results implicate miR-296-5p as a potential cause of invasiveness in cancer and suggest it as a promising therapeutic target for GBM.