Prediction and preliminary validation of oncogene regulation by miRNAs

Springer Science and Business Media LLC - Tập 8 - Trang 1-14 - 2007
Edyta Koscianska1,2, Vesselin Baev1,3, Konstantinia Skreka1,4, Katerina Oikonomaki1,4, Ventsislav Rusinov1,3, Martin Tabler1, Kriton Kalantidis1
1Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology, Heraklion/Crete, Greece
2Laboratory of Cancer Genetics, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, Poland
3Department of Plant Physiology and Molecular Biology, University of Plovdiv, Plovdiv, Bulgaria
4Department of Biology, University of Crete, Heraklion, Greece

Tóm tắt

MicroRNAs (miRNAs) are one of the most abundant groups of regulatory genes in multicellular organisms, playing important roles in many fundamental cellular processes. More than four hundred miRNAs have been identified in humans and the deregulation of miRNA expression has been also shown in many cancers. Despite the postulated involvement of miRNAs in tumourigenesis, there are only a few examples where an oncogene or a tumour suppressor has been identified as a miRNA target. Here, we present an in silico analysis of potential miRNA- oncogene interactions. Moreover, we have tested the validity of two possible interactions of miRNAs with genes related to cancer. We present evidence for the down-regulation of c-MYC, one of the most potent and frequently deregulated oncogenes, by let-7 miRNA, via the predicted binding site in the 3'UTR, and verify the suppression of BCL-2 by miR16. In this work both bioinformatic and experimental approaches for the prediction and validation of possible targets for miRNAs have been used. A list of putative targets for different oncomirs, validation of which would be of special interest, is proposed and two such interactions have been experimentally validated.

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