Peptide nucleic acid-based targeting of microRNAs: possible therapeutic applications for glioblastoma

A large and incremental number of non-coding RNAs, including microRNAs (miRNAs) have been recently demonstrated to play a very important role in human pathologies, including cancer. Therefore, microRNAs have been proposed as therapeutic targets and molecules exhibiting anti-miRNA activity or mimicking functional miRNAs have been developed. Among biomolecules proposed in anti-miRNA therapy, peptide nucleic acids (PNAs) are appealing, in consideration of their stability and efficacy in recognizing RNA targets. PNAs against tumor associated miRNAs have proven to be efficient in inducing anti-tumor effects both in vitro and in vivo. For instance, PNAs targeting miR-155-5p are able to induce apoptosis in glioma cell lines and to enhance the sensitivity to temozolomide (TMZ) in TMZ resistant glioma cells. In vivo, PNAs anti-miR-21 were found to exhibit anti-tumor effects associated with improved survival when administered to animals with intracranial gliomas.