miR-21 and 221 upregulation and miR-181b downregulation in human grade II-IV astrocytic tumors
miR-21 and 221 upregulation and miR-181b downregulation in human grade II-IV astrocytic tumors
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DOI：
10.1007/s11060-009-9797-4
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发表时间：
2009-07-01
影响因子：
3.9
通讯作者：
Tomasello, Francesco
中科院分区：
文献类型：
--
作者：
Conti, Alfredo;Aguennouz, M'Hammed;Tomasello, Francesco
microRNA（miRNAs）是一种小的非编码调节RNA，可降低完全或部分序列互补的靶mRNA的稳定性和/或翻译。最近的证据表明，miRNA既可以作为肿瘤抑制因子，也可以作为癌基因。已经证明，在多形性胶质母细胞瘤中，miR-21和221上调，而miR-128和181下调。应用实时定量逆转录聚合酶链反应（RT-PCR）和北方印迹法（Northern blotting）检测不同恶性程度星形细胞肿瘤中miR-21、221、128 a、128 b、128 c、181 a、181 b、181 c的表达。与正常脑组织相比，miR-21和221在胶质瘤样品中过表达，而miRNA 181 b下调。miRNA-21在所有肿瘤样本中均高表达，而在高级别胶质瘤中发现更高水平的miRNA-221。本研究是首次对星形细胞肿瘤不同恶性阶段的miRNAs进行分析。在恶性肿瘤的不同阶段的肿瘤中观察到的不同表达模式可能取决于共享不同分子途径活性的肿瘤靶基因的细胞特异性库，并且表明miRNA在脑肿瘤的诊断和分期中也可能具有一席之地。
MicroRNAs (miRNAs) are small noncoding regulatory RNAs that reduce stability and/or translation of fully or partially sequence-complementary target mRNAs. Recent evidence indicates that miRNAs can function both as tumor suppressors and as oncogenes. It has been demonstrated that in glioblastoma multiforme miR-21 and 221 are upregulated whereas miR-128 and 181 are downregulated. Expression of miR-21, 221, 128a, 128b, 128c, 181a, 181b, 181c was studied using real-time quantitative reverse transcriptase polymerase chain reaction and northern blotting for human astrocytic tumors with different grade of malignancy. miR-21 and 221 were overexpressed in glioma samples, whereas miRNA 181b was downregulated compared with normal brain tissue. miRNA-21 was hyperexpressed in all tumor samples whereas higher levels of miRNA-221 were found in high-grade gliomas. This study is the first analysis of miRNAs in astrocytic tumor at different stages of malignancy. The different expression pattern observed in tumors at different stages of malignancy is probably dependent on the cell-specific repertoire of target genes of tumors sharing different molecular pathways activity and suggests miRNAs may have also a place in diagnosis and staging of brain tumors.