Dual-color imaging of nascent blood vessels vascularizing pancreatic cancer in an orthotopic model demonstrates antiangiogenesis efficacy of gemcitabine.
BACKGROUND
The stem cell marker nestin recently has been shown to be expressed in nascent blood vessels in nestin-driven green fluorescent protein (ND-GFP) transgenic nude mice.


METHODS
In the present study, we visualized by dual-color fluorescence imaging tumor angiogenesis in the ND-GFP transgenic nude mice after orthotopic transplantation of the MIA PaCa-2 human pancreatic cancer line expressing red fluorescent protein. Mice were treated with gemcitabine at 150 mg/kg/dose on days 3, 6, 10, and 13 after tumor implantation. At day 14, mice were sacrificed and mean nascent blood vessel density and tumor volume were calculated and compared to control mice.


RESULTS
Nestin was highly expressed in proliferating endothelial cells and nascent blood vessels in the growing tumor. Results of immunohistochemical staining showed that CD31 co-localized in ND-GFP-expressing nascent blood vessels. The density of nascent blood vessels in the tumor was readily quantitated. Gemcitabine significantly decreased the mean nascent blood vessel density in the tumor as well as decreased tumor volume.


CONCLUSIONS
The dual-color model of the ND-GFP nude mouse orthotopically implanted with RFP-expressing pancreatic tumor cells enabled the simultaneous visualization and quantitation of tumor angiogenesis and tumor volume. These results demonstrated for the first time that gemcitabine is an inhibitor of angiogenesis as well as tumor growth in pancreatic cancer. The results have important implications for the clinical application of gemcitabine in this disease.
Amoh
Yasuyuki
Y
Department of Surgery, University of California San Diego, San Diego, California, USA.
Li
Lingna
L
Tsuji
Kazuhiko
K
Moossa
A R
AR
Katsuoka
Kensei
K
Hoffman
Robert M
RM
Bouvet
Michael
M
D020533:Angiogenesis Inhibitors / Q000627:therapeutic use*; D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000627:therapeutic use; D003841:Deoxycytidine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D004730:Endothelium, Vascular / Q000737:chemistry; D049452:Green Fluorescent Proteins / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D007381:Intermediate Filament Proteins / Q000032:analysis / Q000235:genetics; D051379:Mice; D008819:Mice, Nude; D008822:Mice, Transgenic; D008856:Microscopy, Fluorescence; D009368:Neoplasm Transplantation; D009389:Neovascularization, Pathologic / Q000188:drug therapy*; D009419:Nerve Tissue Proteins / Q000032:analysis / Q000235:genetics; D064231:Nestin; D010190:Pancreatic Neoplasms / Q000098:blood supply* / Q000188:drug therapy; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000032:analysis; D014162:Transfection; D014183:Transplantation, Heterologous; D000093542:Gemcitabine
D020533:Angiogenesis Inhibitors; D000964:Antimetabolites, Antineoplastic; D007381:Intermediate Filament Proteins; C577484:NES protein, human; D009419:Nerve Tissue Proteins; C577485:Nes protein, mouse; D064231:Nestin; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D003841:Deoxycytidine; D049452:Green Fluorescent Proteins; D000093542:Gemcitabine