Targeting tissue factor-expressing tumor angiogenesis and tumors with EF24 conjugated to factor VIIa.
Tissue factor (TF) is aberrantly expressed on tumor vascular endothelial cells (VECs) and on cancer cells in many malignant tumors, but not on normal VECs, making it a promising target for cancer therapy. As a transmembrane receptor for coagulation factor VIIa (fVIIa), TF forms a high-affinity complex with its cognate ligand, which is subsequently internalized through receptor-mediated endocytosis. Accordingly, we developed a method for selectively delivering EF24, a potent synthetic curcumin analog, to TF-expressing tumor vasculature and tumors using fVIIa as a drug carrier. EF24 was chemically conjugated to fVIIa through a tripeptide-chloromethyl ketone. After binding to TF-expressing targets by fVIIa, EF24 will be endocytosed along with the drug carrier and will exert its cytotoxicity. Our results showed that the conjugate inhibits vascular endothelial growth factor-induced angiogenesis in a rabbit cornea model and in a Matrigel model in athymic nude mice. The conjugate-induced apoptosis in tumor cells and significantly reduced tumor size in human breast cancer xenografts in athymic nude mice as compared with the unconjugated EF24. By conjugating potent drugs to fVIIa, this targeted drug delivery system has the potential to enhance therapeutic efficacy, while reducing toxic side effects. It may also prove to be useful for treating drug-resistant tumors and micro-metastases in addition to primary tumors.
Shoji
Mamoru
M
Winship Cancer Institute, Emory University, Atlanta, GA 30322, USA. mshoji@emory.edu
Sun
Aiming
A
Kisiel
Walter
W
Lu
Yang J
YJ
Shim
Hyunsuk
H
McCarey
Bernard E
BE
Nichols
Christopher
C
Parker
Ernest T
ET
Pohl
Jan
J
Mosley
Cara A
CA
Alizadeh
Aaron R
AR
Liotta
Dennis C
DC
Snyder
James P
JP
D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage*; D001597:Benzylidene Compounds / Q000008:administration & dosage*; D045744:Cell Line, Tumor; D004705:Endocytosis; D015942:Factor VIIa / Q000008:administration & dosage*; D006801:Humans; D051379:Mice; D009374:Neoplasms, Experimental / Q000098:blood supply / Q000188:drug therapy*; D009389:Neovascularization, Pathologic / Q000188:drug therapy*; D010881:Piperidones / Q000008:administration & dosage*; D011817:Rabbits; D013925:Thromboplastin / Q000032:analysis / Q000037:antagonists & inhibitors* / Q000502:physiology; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors; D023041:Xenograft Model Antitumor Assays
C524042:3,5-bis(2-fluorobenzylidene)piperidin-4-one; D000970:Antineoplastic Agents; D001597:Benzylidene Compounds; D010881:Piperidones; D042461:Vascular Endothelial Growth Factor A; D013925:Thromboplastin; D015942:Factor VIIa