Immunotherapy of hepatoma with a monoclonal antibody against murine endoglin.
OBJECTIVE
To explore the capability of a monoclonal antibody (mAb) against murine endoglin to inhibit tumor angiogenesis and suppression of hepatoma growth in murine models.


METHODS
A monoclonal antibody against murine endoglin was purified by affinity chromatography and passively transfused through tail veins in two murine hepatoma models. Tumor volume and survival time were observed at three-day intervals for 48 d. Microvessels in tumor tissues were detected by immunohistochemistry against CD31, and angiogenesis in vivo was determined by alginate encapsulated assay. In addition, tumor cell apoptosis was detected by TUNEL assay.


RESULTS
Passive immunotherapy with anti-endoglin mAb could effectively suppress tumor growth, and prolonged the survival time of hepatoma-bearing mice. Angiogenesis was apparently inhibited within the tumor tissues, and the vascularization of alginate beads was also reduced in the mice passively transfused with anti-endoglin mAb. In addition, increased apoptotic cells were observed within the tumor tissues from the mice passively transfused with anti-endoglin mAb.


CONCLUSIONS
Passive immunotherapy with anti-endoglin mAb effectively inhibits tumor growth via inhibiting tumor angiogenesis and increasing tumor cell apoptosis, which may be highly correlated with the blockage of endoglin-related signal pathway induced by anti-endoglin mAb.
Tan
Guang-Hong
GH
Hainan Provincial Key Laboratory of Tropical Medicine, Hainan Medical College, Haikou 571101, Hainan Province, China. tanhoho@163.com
Huang
Feng-Ying
FY
Wang
Hua
H
Huang
Yong-Hao
YH
Lin
Ying-Ying
YY
Li
Yue-Nan
YN
D000464:Alginates; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000627:therapeutic use*; D017209:Apoptosis / Q000187:drug effects; D045744:Cell Line, Tumor; D004195:Disease Models, Animal; D000071063:Endoglin; D020723:Glucuronic Acid; D006603:Hexuronic Acids; D007116:Immunization, Passive / Q000379:methods*; D047908:Intracellular Signaling Peptides and Proteins / Q000276:immunology*; D008114:Liver Neoplasms, Experimental / Q000098:blood supply / Q000188:drug therapy* / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008819:Mice, Nude; D008863:Microspheres; D009389:Neovascularization, Pathologic / Q000188:drug therapy; D011897:Random Allocation; D015398:Signal Transduction / Q000187:drug effects; D015996:Survival Rate
D000464:Alginates; D000911:Antibodies, Monoclonal; D000071063:Endoglin; C502004:Eng protein, mouse; D006603:Hexuronic Acids; D047908:Intracellular Signaling Peptides and Proteins; D020723:Glucuronic Acid