Figure 4
Expression patterns of type I and type IV collagen and their effect on cell growth. A. Double staining of type I (in green) and type IV collagen (in red) in a pancreatic adenocarcinoma. Cell nuclei are stained by DAPI (in blue). Type I collagen is predominantly found in the desmoplastic reaction (D) that surrounds and partly infiltrates clusters of tumor cells (T). Type IV collagen is highly expressed in close proximity to the tumor cells with lower expression in the desmoplastic area. Magnification x40. B. Growth of pancreatic cancer cells on different matrices after 2 days of incubation. Both type I and type IV collagens promote growth when compared to BSA (used as control protein) in all different coating concentrations (p < 0.05). C. Apoptosis measured with the M30-Apoptosense® ELISA after 48 h incubation in serum free conditions with cells grown on different matrices. Type IV collagen inhibits induction of apoptosis compared to a control BSA matrix (* indicates p < 0.05 compared to BSA). D. Time for wound-healing closure for cells grown on different matrices (coated with 0.5 μg/cm2). * indicates p < 0.05 compared to BSA. Picture-inserts represent the size of the wound at 445 minutes, when the wound on the type I collagen matrix was closed (dotted line indicates cell front). Figures B, C, and D are all based on data from HPAC, but similar results were observed for CFPAC-1.