Figure 7. Investigation of GPC1’s role in adhesion of GBM cells.

Control GBM cells (U-251 MG and C-) and GPC1-silenced GBM cells (C12, C15, and C23) were assessed for their adhesion properties on laminin, collagen IV and vitronectin, using, as experimental controls, the absence of substrates or BSA blocking of the dish. The experiment was conducted for 2 or 4 h before (A) staining with crystal violet and imaging through an optical microscope. The scale bar refers to 1,000 µm. (B) The dye was solubilized with 10% acetic acid, and absorbance was measured. The OD₅₇₀ values were normalized to the condition of the absence of a substrate in the original cell line (U-251 MG) at the time of 2 h. (C) Otherwise, absorbance values were non-linearly fitted to three-parameter sigmoid models to inspect kinetic models for the adhesion profile for each cell line in each studied condition. Data are shown as mean ± SEM and were analyzed with either two- (in B) or one-way (in C) ANOVA with Dunnett’s post hoc test. Statistically significant comparisons are marked as follows: ^* p < 0.05, ^** p < 0.01, ^*** p < 0.001, ^**** p < 0.0001 vs. U-251 MG; and ^# p < 0.05, ^## p < 0.01 vs. C-.