TY - JOUR
T1 - Therapeutic efficacy of replication-competent retrovirus vector-mediated suicide gene therapy in a multifocal colorectal cancer metastasis model
AU - Hiraoka, Kei
AU - Kimura, Takahiro
AU - Logg, Christopher R.
AU - Tai, Chien Kuo
AU - Haga, Kazunori
AU - Lawson, Gregory W.
AU - Kasahara, Noriyuki
N1 - Copyright:
Copyright 2009 Elsevier B.V., All rights reserved.
PY - 2007/6/1
Y1 - 2007/6/1
N2 - Replication-competent retrovirus (RCR) vectors are intrinsically incapable of infecting quiescent cells and have been shown to achieve highly efficient and tumor-restricted replicative spread and gene transfer in vivo after direct intratumoral injection in a variety of primary cancer models. However, i.v. delivery of RCR vectors expressing therapeutic genes has never previously been tested, particularly in an immunocompetent tumor model. Therefore, in the present study, we sought to test the therapeutic effect of an RCR vector (ACE-CD) carrying the yeast cytosine deaminase (CD) gene, which converts the nontoxic prodrug 5-fluorocytosine (5FC) into the chemotoxin 5-fluorouracil, after delivery by infusion into the locoregional circulation in a multifocal hepatic metastasis model of colon cancer. After confirmation of suicide gene cytotoxicity in vitro, multifocal hepatic tumors were established in syngeneic mice with murine CT26 colorectal cancer cells expressing firefly luciferase (CT26.FLuc), and the ACE-CD vector was infused via intrasplenic injection into the portal circulation. Fourteen days after locoregional infusion, systemic administration of 5FC resulted in significant inhibition of bioluminescent signals in mice whose tumors had been infected with RCR but not in control mice. Notably, there was no detectable RCR vector spread to normal liver or bone marrow by quantitative PCR analysis. Our results thus show that locoregional delivery of a suicide gene by RCR vectors infused into the portal circulation results in progressive transduction of multiple tumor foci in the liver, without evidence of spread to adjacent normal parenchyma or extrahepatic tissues, and can achieve significant tumor growth inhibition.
AB - Replication-competent retrovirus (RCR) vectors are intrinsically incapable of infecting quiescent cells and have been shown to achieve highly efficient and tumor-restricted replicative spread and gene transfer in vivo after direct intratumoral injection in a variety of primary cancer models. However, i.v. delivery of RCR vectors expressing therapeutic genes has never previously been tested, particularly in an immunocompetent tumor model. Therefore, in the present study, we sought to test the therapeutic effect of an RCR vector (ACE-CD) carrying the yeast cytosine deaminase (CD) gene, which converts the nontoxic prodrug 5-fluorocytosine (5FC) into the chemotoxin 5-fluorouracil, after delivery by infusion into the locoregional circulation in a multifocal hepatic metastasis model of colon cancer. After confirmation of suicide gene cytotoxicity in vitro, multifocal hepatic tumors were established in syngeneic mice with murine CT26 colorectal cancer cells expressing firefly luciferase (CT26.FLuc), and the ACE-CD vector was infused via intrasplenic injection into the portal circulation. Fourteen days after locoregional infusion, systemic administration of 5FC resulted in significant inhibition of bioluminescent signals in mice whose tumors had been infected with RCR but not in control mice. Notably, there was no detectable RCR vector spread to normal liver or bone marrow by quantitative PCR analysis. Our results thus show that locoregional delivery of a suicide gene by RCR vectors infused into the portal circulation results in progressive transduction of multiple tumor foci in the liver, without evidence of spread to adjacent normal parenchyma or extrahepatic tissues, and can achieve significant tumor growth inhibition.
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U2 - 10.1158/0008-5472.CAN-06-4673
DO - 10.1158/0008-5472.CAN-06-4673
M3 - Article
C2 - 17545615
AN - SCOPUS:34347225590
VL - 67
SP - 5345
EP - 5353
JO - Cancer Research
JF - Cancer Research
SN - 0008-5472
IS - 11
ER -