Figure 4. Influence of irradiation on adhesion and migration. Left panel: adhesion assay: untreated or treated cells were seeded with 1 × 105 cells per well in fibronectin-coated 24-well plates and allowed to adhere. Non-adherent cells were washed away and the remaining cells were stained with crystal violet. Cells were lysed and absorbance of cell lysates was measured. Four independent experiments were performed each in quadruplicate. Symbols represent means ± SEM, (p ≤ 0.05, two-tailed), *, vs. 0 Gy; Mann-Whitney U test. Right panel: untreated or treated cells were seeded with 2 × 105 cells in the upper compartment of a Boyden chamber. Cells were allowed to migrate through the 8 µm pores of a membrane toward chemoattractant and stained with calcein. Fluorescence signal of the cells was measured at 485/528 nm and relative migration was calculated as fluorescence units of samples with chemoattractant (10% FCS) vs. control samples (0% FCS). Three independent experiments were performed, each in triplicate. Symbols represent means ± SEM, (p ≤ 0.05), *, vs. 0 Gy; ANOVA, Bonferroni post hoc method.