中文摘要：

miRNAs是一类非编码的小单链RNA，可以调控转录后基因表达。最近的研究发现，miRNAs与多种人类肿瘤相关，并且在人类肿瘤的发生、发展中起重要作用，miRNAs可以调节肿瘤细胞增殖、细胞凋亡、血管生成、免疫反应以及侵袭和转移，并且miRNAs对于肿瘤的诊断和治疗也有一定意义。因此，miRNAs的研究对于揭示基因表达的调控机理以及人类肿瘤的防治具有重要的意义。

英文摘要：

MicroRNAs （miRNAs） are small non-coding RNAs that function as post-transcriptionally regulators. Recent studies have found that miRNAs correlate with various human cancers and play an important role in the oc- currence and development of human cancers. MicroRNAs can regulate tumor cell proliferation, apoptosis, angiogene- sis, immune response, as well as invasion and metastasis. And the identification of miRNAs may contribute to cancer diagnosis and treatment. Therefore, miRNAs study reveals the mechanism of regulation of gene expression and great significance of the prevention and treatment of human cancers.