FIGURE 1.

miR-542-3p is down-regulated in astrocytoma and inhibits invasion of glioblastoma cells. A, relative expression of miR-542-3p in a panel of human astrocytoma cell lines, including U87MG, T98G, U118MG, A172, U251MG, and LN464, and normal human astrocytes (NHA) were quantified by real time RT-PCR. B, relative expression of miR-542-3p in five pairs of astrocytoma tissues (Tumor) and matched adjacent non-cancerous brain tissues (ANT). The average miR-542-3p expression was normalized by U6 expression. C, Kaplan-Meier analysis of overall survival of astrocytoma patients divided into the low miR-542-3p expression group (less than the median; n = 30) and the high miR-542-3p expression group (greater than the median; n = 29). D, three-dimensional invasion assays revealed that miR-542-3p-overexpressing cells form space frame structure with fewer and shorter projections than those formed by control cells grown in Matrigel for 5 days. E, representative micrographs show the effect of miR-542-3p on glioblastoma cell invasion as evaluated by Matrigel invasion assay. F, the relative percentages of the indicated infiltrated cells comparing miR-542-3p-overexpression with control transfection. G, Western blotting analysis of protein expression of MMP-2 in the indicated miR-542-3p-overexpressing cells and control cells. H, gelatin zymography assay and quantitative data of the proteolytic bands show differential MMP-2 activity in supernatants derived from the indicated cells. Error bars represent mean ± S.D. derived from three independent experiments. *, p < 0.05.