MicroRNA profiling of human glioblastoma cell lines and tissue samples identifies microRNAs whose expression is altered in glioblastoma multiforme

MicroRNAs are short non-coding RNA molecules playing regulatory roles in animals and plants by repressing translation or cleaving RNA transcripts. The specific modulation of several microRNAs has been recently associated to some forms of human cancer, suggesting that these short molecules can represent a new class of genes involved in oncogenesis. In our study, we examined by microarray the global expression levels of 245 microRNAs in glioblastoma multiforme (GBM), the most frequent and malignant of primary brain tumors. The analysis of both glioblastoma tissues and glioblastoma cell lines allowed us to identify a group of microRNAs whose expression is significantly altered in this tumor. The most interesting results came from miR-221, strongly upregulated in glioblastoma and a set of brain-enriched miRNAs, miR-128, miR-181a, miR-181b, miR-181c, which are down-regulated in glioblastoma.