Tum-1, a tumstatin fragment, gene delivery into hepatocellular carcinoma suppresses tumor growth through inhibiting angiogenesis.
Since hepatocellular carcinoma (HCC) is a hypervascular cancer, anti-angiogenic therapy is a promising approach to treat HCC. In the present study, we investigated the antiangiogenic and antitumor effects of tum-1, a fragment of tumstatin, gene transduction into HCC in vitro and in vivo. Tum-1 gene was cloned into a pSecTag2B mammalian expression vehicle to construct pSecTag2B-tum-1. pSecTag2B-tum-1 or vehicle were transfected into human HCC cells, PLC/PRF/5 cells stably and Huh-7 cells tran-siently. pSecTag2B-tum-1 transfection slightly repressed the proliferation of both PLC/PRF/5 and Huh-7 cells in vitro. Addition of conditioned media (CM) from tum-1 expressing PLC/PRF/5 cells significantly inhibited the spontaneous and vascular endothelial growth factor (VEGF)-induced proliferation and migration of human umbilical vein endothelial cells (HUVEC) in vitro with diminishing the VEGF-induced phosphorylation of both Akt and extracellular signal-regulated kinase (ERK) that are known to mediate VEGF-induced proliferation and migration of endothelial cells. In in vivo experiments, intratumoral injection of pSecTag2B-tum-1 significantly repressed the growth of pre-established Huh-7 tumors in athymic mouse models accompanying the decreased density of CD34 positive vessels in tumors. In conclusion, our results suggest that antiangiogenic gene therapy using tum-1 gene may be an efficient strategy for the treatment of HCC.
First Department of Internal Medicine, Nagasaki University School of Medicine, Nagasaki 852-8501, Japan.
Takashi
T
Goto
Hiroki
H
Ishikawa
Kojiro
K
Matsumoto
Daisuke
D
Nishimura
Mariko
M
Kusaba
Naota
N
Taura
Hidetaka
H
Shibata
Hisamitsu
H
Miyaaki
Tatsuki
T
Ichikawa
Keisuke
K
Hamasaki
Kazuhiko
K
Nakao
Yohei
Y
Maeshima
Katsumi
K
Eguchi
D000818:Animals; D001324:Autoantigens / Q000235:genetics*; D006528:Carcinoma, Hepatocellular / Q000098:blood supply / Q000473:pathology / Q000628:therapy*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D024141:Collagen Type IV / Q000235:genetics*; D042783:Endothelial Cells / Q000502:physiology; D015316:Genetic Therapy; D006801:Humans; D008113:Liver Neoplasms / Q000098:blood supply / Q000473:pathology / Q000628:therapy*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009389:Neovascularization, Pathologic / Q000517:prevention & control*; D010446:Peptide Fragments / Q000235:genetics*; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology; D000081082:Phosphoinositide-3 Kinase Inhibitors; D010766:Phosphorylation; D051057:Proto-Oncogene Proteins c-akt / Q000037:antagonists & inhibitors / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects; D042461:Vascular Endothelial Growth Factor A / Q000494:pharmacology
D001324:Autoantigens; D024141:Collagen Type IV; D010446:Peptide Fragments; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D051057:Proto-Oncogene Proteins c-akt; D042461:Vascular Endothelial Growth Factor A; C057112:type IV collagen alpha3 chain