Title:Antibody-directed Double Suicide Gene Therapy Targeting of MUC1- Positive Leukemia Cells In Vitro and In Vivo
Volume: 13
Issue: 5
Author(s): Xiao-Ya Dong, Wen-Qian Wang, Yu Zhao, Xu-Dong Li, Zhi-Gang Fang, Dong-Jun Lin, Ruo-Zhi Xiao, Ren-Wei Huang, Guang-Jin Pan and Jia-Jun Liu
Affiliation:
Keywords:
Leukemia, dual suicide gene therapy, lentiviral vector, cytosine deaminase, thymidine kinase.
Abstract: Our aim was to specifically transfer the cytosine deaminase (CD) and thymidine kinase (TK) genes into mucin
1 (MUC1)-positive leukemia cells by anti-MUC1 antibody directed infection of replication-defective lentivirus and to
evaluate the targeted cytotoxicity of double suicide genes to leukemia. The target gene vector (containing CD and TK)
and envelope (containing GFP and anti-MUC1) and packaging plasmids were cotransfected into 293T cells to produce the
recombinant lentivirus. Suicide genes in virus-infected leukemia cells (U937, Jurkat, and K562) were detected by western
blot. The cytotoxicity and bystander effect in vitro and the therapeutic effect in vivo were detected after treatment with the
prodrugs. The results revealed that combined treatment with prodrug 5-fluorocytosine (5-FC) and ganciclovir (GCV) inhibited
leukemia cell growth and caused significant bystander effect than treatment with either prodrug alone. TK/GCV
treatment alone induced degeneration and cell death while the effect of CD/5-FC alone mainly caused vacuolar degeneration
and necrosis. The addictive effects of combinatorial use of GCV and 5-FC mainly induced swelling of the mitochondria
followed by necrosis of the leukemia cells. In vivo experiments revealed that both single and combinatorial prodrug
treatments could prolong the survival time of leukemic mice. In summary, anti-MUC1 antibody directed lentiviral vector
successfully transduced dual suicide genes and exerted targeted cytotoxicity against MUC1 positive leukemia cells. This
targeted lentiviral dual suicide gene delivering system provides a promising approach for clinical treatment of leukemia in
future.
