2.7. MTT Assay

Logarithmically growing glioma cells (U87 and U251) with different treatments were plated into 96-well culture clusters (Costar, Cambridge, MA, USA), at a density of 2000 cells/well and cultured for different time points (0, 24, 48, 72 hr). Cell viability was assessed by adding 10 μl MTT (0.5 mg/ml) to each well and incubated for 4 hr. After removing the cell medium, 100 μl DMSO was added, and cell proliferation was measured at 490 nm wavelength. Measurements of cell viability for each treatment were done in triplicates from three independent experiments. Treatments included (1) anti-miR-21, (2) sh-CXCR4, (3) anti-miR-21 + sh-CXCR4, and (4) Lv-NC.