MicroRNAs, as short endogenous non-coding RNAs, play an important role in post-transcriptional gene silencing. Altered expression of these miRNAs can contribute to the tumourogenesis and tumour development deregulating the expression of key cancer genes. Our study aimed at highlighting specific signatures (i) of the invasive phenotype of meningiomas (ii) of the aggressive phenotype of gliomas studying oligodendrogliomas (low grade) and glioblastomas (high grade). (i) The invasive phenotype of meningiomas, also established in vitro, is supported by deregulation of some miRNAs. (ii) As for gliomas, several miRNAs discriminate gliomas vs control tissues and some can also distinguish oligodendrogliomas and glioblastomas. Genomics and epigenetics studies have been run to analyse the effect of the deregulation of expression of these miRNAs on the tumoural cell physiopathology. Some targets of these miRNAs, MDH1, SIRT1, STAT3 ou PTBP1, which are key cellular proteins, have been highlighted as deregulated. Our work suggests some new interesting pathways implicated in glioma development.
