Abstract: RNA interference(RNAi) is a newly developed method to negatively regulate gene expression by introduction of homologous double stranded RNA(dsRNA) to specifically act on a gene's product,resulting in the formation of null or hypomorphic phenotypes.Discovered only recently,it has been utilized very successfully to inhibit many tumor cells growth by knocking down some oncogenes expression,suggesting an enthusiastic potential for therapeutic applications.In this review,it summarizes recent views about the mechanism of small interference RNA(siRNA) and microRNA production and process,and the current and future potential in cancer diagnosis and prevention.

Key words: RNA interference, small interfering RNA, gene silencing, tumor