FIG. 4.

Migration and invasion capabilities of spheroids in static vs flow conditions. U-87 MG spheroids (2.5 × 10⁴ cells per well) were formed as previously described. Spheroids were then either incubated in a plate in static conditions (static) or incorporated into flow 2 (Flow 2) device and exposed to flow conditions as before. For these experiments, spheroids were incorporated into the wells or devices with varying hydrogels or media alone, as noted below. (a) and (b) U-87 MG spheroids were incorporated into wells (static) or device chamber (flow 2) containing Matrigel. Scatterplot (a) represents the total area of cellular spread from spheroid over the course of 72 h for all samples of three independent experiments. (b) Representative images of U-87 MG spheroids at 5× magnification under brightfield settings. Scale bar represents 200 μm. (c) and (d) U-87 MG spheroids were incorporated into wells (static) or device chamber (flow 2) containing either media only, collagen, or Matrigel. Scatterplots represent show VEGF (c) and IL-6 (d) concentration in media/effluent samples as determined by ELISA and plotted as picograms per spheroid for three independent experiments. (a), (c), and (d) Error bars represent SEM. Two-way ANOVA was performed to test for statistical significance between samples. *p < 0.05; ***p < 0.001.