Cancer and Metastasis Reviews

, 28:369

MicroRNA function in cancer: oncogene or a tumor suppressor?

NON-THEMATIC REVIEW

DOI: 10.1007/s10555-009-9188-5

Cite this article as:
Shenouda, S.K. & Alahari, S.K. Cancer Metastasis Rev (2009) 28: 369. doi:10.1007/s10555-009-9188-5

Abstract

MicroRNAs (miRNAs) are small noncoding, double-stranded RNA molecules that can mediate the expression of target genes with complementary sequences. About 5,300 human genes have been implicated as targets for miRNAs, making them one of the most abundant classes of regulatory genes in humans. MiRNAs recognize their target mRNAs based on sequence complementarity and act on them to cause the inhibition of protein translation by degradation of mRNA. Besides contributing to development and normal function, microRNAs have functions in various human diseases. Given the importance of miRNAs in regulating cellular differentiation and proliferation, it is not surprising that their misregulation is linked to cancer. In cancer, miRNAs function as regulatory molecules, acting as oncogenes or tumor suppressors. Amplification or overexpression of miRNAs can down-regulate tumor suppressors or other genes involved in cell differentiation, thereby contributing to tumor formation by stimulating proliferation, angiogenesis, and invasion; i.e., they act as oncogenes. Similarly, miRNAs can down-regulate different proteins with oncogenic activity; i.e., they act as tumor suppressors. This review will highlight the recent discoveries regarding miRNAs and their importance in cancer.

Keywords

MicroRNAsCaenorhabditis elegansPri-microRNAUbiquitin-proteosome pathwayDicerEZH2

Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.Department of Biochemistry and Molecular Biology, Stanley S. Scott Cancer CenterLouisiana State University Health Sciences CenterNew OrleansUSA