The microRNA pathway and cancer

MicroRNAs (miRNAs) are similar to 22 nt long, non-coding RNAs that guide post-transcriptional gene silencing of their target genes and regulate diverse biological processes including cancer. miRNAs do not act alone, but require assembly into RNA-induced silencing complex (RISC). In this review, we summarize how miRNAs are produced, assembled into RISC, and regulate target mRNAs, and discuss how the miRNA pathway is involved in cancer. (Cancer Sci 2010; 101: 2309-2315).