Figure 1
From: TGF-β signaling promotes tube-structure-forming growth in pancreatic duct adenocarcinoma
Sphere- and tube-forming clones of YamaPaca and DC cells. (A) Pancreatic cancer cell lines, YamaPaca-6 (a) and YamaPaca-25 (b), and immortalized pancreatic duct epithelial cell lines, DC-11 (c) and DC-19 (d), form spheres and tubes in 3D culture using type I collagen. The isolated sphere-forming cancer or immortalized cell lines are termed YamaPaca-6.12 (e) and YamaPaca-25.12 (f) or DC-11.8 (g) and DC-19.18 (h), respectively. The isolated tube-forming cancer or immortalized cell lines are termed YamaPaca-6.2 (i) and YamaPaca-25.1.1 (j) or DC-11.14 (k) and DC-19.12 (l), respectively. (B) Tube-forming YamaPaca cells express CK19 at a lower level compared with sphere-forming cells. The images show H&E staining and anti-CK19 immunostaining. The arrows and circles indicate the spheres and tubes, respectively, that originated from tube-forming clones. (C) Tube-forming YamaPaca cells express CK19 at a lower level than do sphere-forming cells in the transplanted tumor. The sphere-forming YamaPaca-6.12 clone is transplantable into the abdominal cavity of nude mice, where it develops tumor cells that express CK19. CK19 expression is downregulated in tube-forming cells (circles), which grow invasively and express TAg.
