The goal of the present study was to determine whether
insulin-like growth factor-1 receptor (IGF-1R)
antibodies, conjugated with bright fluorophores, could enable visualization of
pancreatic cancer in orthotopic nude mouse models. IGF-1R antibody (clone 24-31) was conjugated with 550 nm or 650 nm fluorophores. Western blotting confirmed the expression of IGF-1R in Panc-1, BxPC3, and MIAPaCa-2 human
pancreatic cancer cell lines. Labeling with fluorophore-conjugated IGF-1R antibody demonstrated fluorescent foci on the membrane of the
pancreatic cancer cells. Subcutaneous Panc-1, BxPC-3, and MIA PaCa-2
tumors became fluorescent after
intravenous administration of fluorescent IGF-1R
antibodies. Orthotopically-transplanted BxPC-3
tumors became fluorescent with the conjugated IGF-1R
antibodies, and were easily visible with intravital imaging. Gross and microscopic ex vivo imaging of resected pancreatic
tumor and normal pancreas confirmed that fluorescence indeed came from the membrane of
cancer cells, and it was stronger from the
tumor than the normal tissue. The present study demonstrates that fluorophore-conjugated IGF-1R
antibodies can visualize
pancreatic cancer and it can be used with various imaging devices such as endoscopy and laparoscopy for diagnosis and fluorescence-guided surgery.