Up-regulation of micro-RNA-221 (miRNA-221; chr Xp11.3) and caspase-3 accompanies down-regulation of the survivin-1 homolog BIRC1 (NAIP) in glioblastoma multiforme (GBM).

Glioblastoma multiforme (GBM) represents a class of malignant gliomas which rapidly proliferate, invade and destroy surrounding brain tissues. This study examined micro-RNA (miRNA) speciation and miRNA effects on gene expression in six ATCC glioma and GBM cell lines and in 14 glioma and GBM samples obtained from human brain biopsy. We observed selective up-regulation of miRNA-221 and down-regulation of a miRNA-221 messenger RNA target encoding the survivin-1 homolog BIRC1, a neuronal inhibitor of apoptosis protein (NIAP) and marker for neurodegeneration. The expression of BIRC5 (survivin-1) and caspase-3 were found to be significantly up-regulated, particularly in stage IV GBM. These studies suggest that the abundance and speciation of the BIRC family of neural cell fate regulators are differentially regulated in glioma and GBM, and may contribute to progressive changes in apoptotic signaling and altered neural cell cycling functions.