microRNA(miRNA)是一类长度约为21～25个核苷酸RNA,它在转录后水平调节靶基因表达。miRNA在物种进化中相当保守,其表达有组织特异性和时序特异性,其主要功能是负调控基因表达。有研究表明,miRNA在发育、细胞增殖、凋亡、脂类代谢、激素分泌及肿瘤发生等多种生理和病理过程中密切相关。本文着重介绍miRNA的产生,作用机制,与肿瘤的关系,以及在卡波氏肉瘤中的研究进展。 MicroRNAs (miRNAs) are a group of about 21-25 nucleotide RNAs that regulate the expression of a target gene at post-transcriptional levels. MiRNAs are quite conserved in species evolution. Their expression is tissue-specific and time-specific. The main function of miRNAs is to negatively regulate gene expression. Some studies have shown that miRNAs are closely related to various physiological and pathological processes such as development, cell proliferation, apoptosis, lipid metabolism, hormone secretion and tumorigenesis. This article focuses on the generation of miRNAs, the mechanism of action, the relationship with tumors, and the progress in Kaposi’s sarcoma.