Neuropilin-2-mediated tumor growth and angiogenesis in pancreatic adenocarcinoma.
OBJECTIVE
Neuropilin-2 (NRP-2) is a coreceptor for vascular endothelial growth factor (VEGF) on endothelial cells. NRP-2 is overexpressed in pancreatic ductal adenocarcinoma (PDAC) cells relative to nonmalignant ductal epithelium. This study determined the role of NRP-2 in PDAC cells.


METHODS
NRP-2 expression was reduced in PDAC cells with stable short-hairpin RNA (shRNA) transfection. Western blotting was done to evaluate signaling intermediates. Migration and invasion studies were carried out in Boyden chambers. Anchorage-independent growth was assessed by soft-agar colony formation. In vivo growth was evaluated using murine subcutaneous and orthotopic xenograft models. Immunohistochemical analysis evaluated in vivo proliferation and angiogenesis.


RESULTS
shRNA-NRP-2 decreased NRP-2 levels without affecting neuropilin-1 levels. Akt activation was decreased in clones with reduced NRP-2 (shRNA-NRP-2). shRNA-NRP-2 cells showed decreased migration, invasion, and anchorage-independent growth compared with control cells. In vitro proliferation rates were similar in control- and shRNA-transfected cells. Subcutaneous and orthotopic xenografts from shRNA-transfected cells were significantly smaller than those resulting from control-transfected cells (P < 0.05). Furthermore, shRNA-NRP-2 tumors exhibited less cellular proliferation and decreased microvascular area relative to control tumors (P < 0.05). Constitutive expression of the angiogenic mediator Jagged-1 was reduced in shRNA-NRP-2 cells, whereas vascular endothelial growth factor levels were unchanged.


CONCLUSIONS
Reduction of NRP-2 expression in PDAC cells decreased survival signaling, migration, invasion, and ability to grow under anchorage-independent conditions. In vivo, reduction of NRP-2 led to decreased growth of xenograft tumors and decreased vascular area, which was associated with decreased Jagged-1 levels. NRP-2 is a potential therapeutic target on PDAC cells.
Dallas
Nikolaos A
NA
Department of Surgical Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77230-1402, USA.
Gray
Michael J
MJ
Xia
Ling
L
Fan
Fan
F
van Buren
George
G
Gaur
Puja
P
Samuel
Shaija
S
Lim
Sherry J
SJ
Arumugam
Thiruvengadam
T
Ramachandran
Vijaya
V
Wang
Huamin
H
Ellis
Lee M
LM
D000230:Adenocarcinoma / Q000098:blood supply / Q000473:pathology*; D002135:Calcium-Binding Proteins / Q000032:analysis; D021441:Carcinoma, Pancreatic Ductal / Q000098:blood supply / Q000473:pathology*; D045744:Cell Line, Tumor; D002465:Cell Movement; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000032:analysis; D000072100:Jagged-1 Protein; D008565:Membrane Proteins / Q000032:analysis; D009361:Neoplasm Invasiveness; D009389:Neovascularization, Pathologic / Q000209:etiology*; D039943:Neuropilin-2 / Q000032:analysis / Q000502:physiology*; D010190:Pancreatic Neoplasms / Q000098:blood supply / Q000473:pathology*; D000072099:Serrate-Jagged Proteins
D002135:Calcium-Binding Proteins; D036341:Intercellular Signaling Peptides and Proteins; C000606273:JAG1 protein, human; D000072100:Jagged-1 Protein; D008565:Membrane Proteins; D039943:Neuropilin-2; D000072099:Serrate-Jagged Proteins