Gene therapy for colon cancer by adeno-associated viral vector-mediated transfer of survivin Cys84Ala mutant.
OBJECTIVE
Reactivation of survivin expression is involved in carcinogenesis and angiogenesis in colon cancer. Previous in vitro studies showed that mutation of the cysteine residue at position 84 (Cys84Ala) of survivin generates a dominant-negative mutant that triggers mitotic catastrophe and apoptosis. We investigated the therapeutic effect of the adeno-associated virus (AAV)-mediated survivin mutant (Cys84Ala) on colon cancer.


METHODS
Survivin mutant (Cys84Ala) (Sur-Mut(Cys84Ala)) was cloned into the AAV expression vector pAM/CAG-WPRE.poly(A) to generate recombinant AAV-Sur-Mut(Cys84Ala) virus. Cell proliferation, apoptosis, mitotic catastrophe, and tumor growth were measured in vitro and in vivo.


RESULTS
Transduction of colon cancer cells with rAAV-Sur-Mut(Cys84Ala) inhibited cell proliferation and induced apoptosis and mitotic catastrophe in vitro. rAAV-Sur-Mut(Cys84Ala) sensitized colon cancer cells to chemotherapeutic drugs. Furthermore, expression of survivin mutant mediated by AAV inhibited tumorigenesis in colon cancer cells. Intratumoral injection of rAAV-Sur-Mut(Cys84Ala) significantly induced apoptosis and mitotic catastrophe and inhibited angiogenesis and tumor growth in a colon cancer xenograft model in vivo. No obvious cytotoxicity to other tissues was observed. More importantly, rAAV-Sur-Mut(Cys84Ala) expression strongly enhanced the antitumor activity of 5-Fluorouracil (5-FU), resulting in regression of established tumors.


CONCLUSIONS
Our results showed that rAAV-Sur-Mut(Cys84Ala) induced apoptosis and mitotic catastrophe and inhibited tumor angiogenesis and tumor growth. Thus, use of AAV-mediated survivin mutant (Cys84Ala) is a promising strategy in colon cancer gene therapy.
Tu
Shui Ping
SP
Department of Gastroenterology, Rui-jin Hospital, Shanghai, P.R. China.
Cui
Jian Tao
JT
Liston
Peter
P
Huajiang
Xiao
X
Xu
Ruian
R
Lin
Marie C M
MC
Zhu
Yan Bo
YB
Zou
Bing
B
Ng
Samuel S M
SS
Jiang
Shi Hu
SH
Xia
Harry H X
HH
Wong
Wai Man
WM
Chan
Annie O O
AO
Yuen
Man Fung
MF
Lam
Shiu Kum
SK
Kung
Hsiang Fu
HF
Wong
Benjamin C Y
BC
D000409:Alanine; D019943:Amino Acid Substitution; D017209:Apoptosis; D002455:Cell Division; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000235:genetics* / Q000473:pathology / Q000628:therapy*; D003545:Cysteine; D000229:Dependovirus / Q000235:genetics*; D018014:Gene Transfer Techniques; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins / Q000235:genetics*; D008938:Mitosis; D020125:Mutation, Missense; D009363:Neoplasm Proteins; D000077022:Survivin
C107489:BIRC5 protein, human; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D000077022:Survivin; D003545:Cysteine; D000409:Alanine