MicroRNAs and Apoptosis

摘要

MicroRNAs (miRNAs) are small non-coding RNAs of 19-25 nucleotides that post-transcriptionally regulate the expression of target mRNA transcripts. They have been found involved in different processes commonly altered during tumorigenesis such as proliferation, differentiation and apoptosis. Here we will overview the last insights about microRNAs and apoptosis with the focus on two related miRs, miR-221&222, found involved in the resistance to TRAIL-inducing apoptosis and in the increased tumorigenesis of several types of cancers. Mounting evidence indicates that miRNA plays a fundamental role in tumorigenesis, controlling cell proliferation and apoptosis. Some miRNAs, such as miR-34 family, miR-15-16, have been shown to influence only the apoptotic pathway, whereas others, including miR-221&222, may play roles in both the apoptotic and cell-proliferation pathways (fig. 1). MiR-221&222 are among the most deregulated miRNAs implicated in cancer [8]. Their expression is highly upregulated in a variety of solid tumors, including thyroid cancern, hepatocarcinoma and melanoma cells.