中文摘要：

MicroRNA（miRNA）是一类内源性非编码小RNA。MiRNA通过与蛋白编码基因mRNA的3’非编码区互补配对，影响mRNA的稳定和抑制蛋白质的合成，从而发挥转录后调控作用。研究表明miRNA靶位点单核苷酸多态性可能会通过影响miRNA对靶基因的负调控，参与肿瘤的发生、发展及其耐药。

英文摘要：

MicroRNAs （miRNAs） are a family of endogenous, small non-coding RNAs that affect posttranscriptional regulation by pairing to the 3＇untranslated region （UTR） of messenger RNA （mRNA） of protein-coding genes, therefore affect mRNA stability and repress protein synthesis. Studies have shown that single nucleotide polymorphism in miRNA target sites may affect the role of miRNA in regulation of their target genes, which in turn participates in tumorigenesis, development and drug resistance.