Activation of fibroblasts under co-culture with 3D tumor spheroids.

<p>(A) Fluorescence images of fibroblasts stained for F-actin and α-SMA showing differential expression levels under mono- and co-culture conditions. (B) Increased migration ability of fibroblasts towards 3D tumor compartment. A picture for a representative regions showing fibroblast migrated out of the designated channel and comparison of migration distance. The migration distance of fibroblasts was measured between the nucleus of fibroblast in medium channel and end of fibroblast culture channel. Cells were grown for 6 days before all measurements. Optical sections were acquired at 3 μm intervals and stacked into a z-projection from which fluorescence intensity was calculated. Student t-test was used to test the statistical significance. Data are expressed as the mean ± SE of 3 replicates. (Scale bars 200 μm, 100 μm). * p<0.05.