Morphological analysis of 3D cultured Panc-1 cells. [A] Hematoxilin Eosin staining and [B-D] electron microscopy analysis of a central 7 days spheroid section. C and D show details of the same section at EM. In C the arrow indicates the presence of a lumen. In D tight junction structures are indicated by arrows. [E] E-cadherin expression in both 2D and 3D culture assessed by RT-PCR. Data are calculated as expression ratio 3D/2D. [F] Western blotting shows E-cadherin protein expression in 2D and 3D culture on day 4 and 7.