[Anti-tumor effects of recombinant adenovirus encoding survivin encapsulated in cationic liposome].
OBJECTIVE
To explore the anti-tumor effects and mechanisms of recombinant adenovirus encoding survivin encapsulated in cationic liposome.


METHODS
CT26 tumor model was established in BALB/c mice. Fifty mice were randomly divided into five groups, including the group treated with recombinant adenovirus encoding survivin encapsulated in cationic liposome (Lip+ Ad-sur), the group of recombinant adenovirus encoding survivin (Ad-sur), the group of recombinant adenovirus encoding null encapsulated in cationic liposome (Lip+Ad-null), the group of liposome (Lip), and the group of PBS alone (PBS). Survival rate of mice, tumor volume, and side effects of treatments were observed. Lymphocytes were activated by adenovirus vaccine to kill tumor cells in vitro and in vivo. CTL assay and histological examination were carried out.


RESULTS
Immunotherapy with recombinant adenovirus encoding survivin encapsulated in cationic liposome was effective for inducing protective and therapeutic anti-tumor immunity in CT26 tumor model. In the combination therapy group, the tumor growth was inhibited and the tumor volume was significantly smaller when compared with the controls. The survival rate of mice in the combination therapy group at 7 weeks after inoculation of tumor cells was significantly higher than that of the control group. Histologically, the tumor tissue was markedly necrotic and was infiltrated by lymphocytes. 51Cr assay in vitro indicated that the combination therapy group showed higher specific killing activity against CT26 tumor cells than did the control groups, and the T cells were independent of NK cells.


CONCLUSIONS
Immunotherapy with recombinant adenovirus encoding survivin encapsulated in cationic liposome was noted to have a significant anti-tumor effect on CT26 tumor model.
Yang
Ya-li
YL
State Key Laboratory of Biotherapy of Cancer, West China Hospital, Sichuan University, Chengdu 610041, China.
Ding
Zhen-yu
ZY
Li
Qiu
Q
Zhou
Hang
H
Deng
Hong-xin
HX
Tian
Ling
L
Wei
Yu-quan
YQ
D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D002412:Cations; D003110:Colonic Neoplasms / Q000628:therapy*; D005260:Female; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors / Q000008:administration & dosage; D051034:Inhibitor of Apoptosis Proteins; D008081:Liposomes; D051379:Mice; D008807:Mice, Inbred BALB C; D008869:Microtubule-Associated Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000627:therapeutic use*; D009368:Neoplasm Transplantation; D050130:Oncolytic Virotherapy / Q000379:methods*; D011995:Recombination, Genetic; D012097:Repressor Proteins; D000077022:Survivin
C117749:Birc5 protein, mouse; D002412:Cations; D051034:Inhibitor of Apoptosis Proteins; D008081:Liposomes; D008869:Microtubule-Associated Proteins; D012097:Repressor Proteins; D000077022:Survivin