Adeno-associated virus-mediated expression of kallistatin suppresses local and remote hepatocellular carcinomas.
BACKGROUND
The current treatments for hepatocellular carcinoma (HCC) are poor, particularly for metastatic HCC. Intraportal transfusion of adeno-associated virus (AAV) leads to long-term and persistent transgenic expression in livers. Kallistatin, a novel angiogenesis inhibitor, exhibits anti-tumor activity. The aim of the study was to investigate whether intraportal injection of AAV-kallistatin could suppress local and metastatic HCC in mice.


METHODS
An AAV vector encoding kallistatin was constructed, and its transduction efficiency by intraportal transfusion in livers was examined by RT-PCR, immunohistochemical and Western blotting analysis. The anti-tumor activity was tested in three HCC models including hepatic and subcutaneous human Hep3B HCC tumors in BALB/c athymic (nu/nu) mice, and subcutaneous mouse BNL HCC tumors in BALB/c mice. Tumor cell proliferation in situ was examined by anti-Ki-67 staining, and apoptosis by TUNEL.


RESULTS
Gene transfection by rAAV-kallistatin inhibited proliferation of human umbilical vein endothelial cells and HCC cells in vitro. Intraportal injection of rAAV-kallistatin resulted in persistent and specific expression of kallistatin in livers detected by RT-PCR and immunohistochemical analysis, and kallistatin protein in circulation detected by Western blotting analysis. Intraportal injection of rAAV-kallistatin significantly suppressed angiogenesis and growth of hepatic Hep3B tumors. The kallistatin released by hepatocytes into the circulation suppressed remote Hep3B and BNL tumors established subcutaneously. The rAAV-kallistatin gene therapy significantly inhibited tumor cell proliferation and induced apoptosis.


CONCLUSIONS
Intraportal injection of rAAV-kallistatin suppressed hepatic and subcutaneous HCC tumors, relying on its anti-angiogenic and anti-proliferative activities.
Tse
Lai Yin
LY
Institute of Molecular Medicine, Huaqiao University and Gene Therapy Laboratory, GRC, Hong Kong University, China.
Sun
Xueying
X
Jiang
Hongchi
H
Dong
Xuesong
X
Fung
Peter W C
PW
Farzaneh
Farzin
F
Xu
Ruian
R
D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D006528:Carcinoma, Hepatocellular / Q000628:therapy*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D000229:Dependovirus / Q000235:genetics; D015316:Genetic Therapy / Q000379:methods; D006801:Humans; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D015843:Serpins / Q000008:administration & dosage* / Q000627:therapeutic use; D014161:Transduction, Genetic
D015843:Serpins; C051324:kallistatin