Suicide gene therapy of sarcoma cell lines using recombinant adeno-associated virus 2 vectors

Abstract

Soft-tissue sarcomas are mesenchymal tumors that respond poorly to systemic chemotherapy. Suicide gene therapy may be an alternative treatment strategy. Here we show a high susceptibility of human sarcoma cell lines for recombinant adeno-associated virus 2 (rAAV-2) suicide vectors: connective tissue sarcoma (HS-1), fibrosarcoma (HT-1080), Ewing sarcoma (RD-ES), Askin tumor (SK-N-MC), rhabdomyosarcoma (A-204) and soft-tissue sarcoma (WSKL-1). Several vectors containing the thymidine kinase (TK) gene under the control of either the cytomegalovirus promoter or the elongation-factor 1 alpha (EF1a) promoter were cloned and tested. Higher expression levels of the transgene were observed in the sarcoma lines when using the EF1a-suicide gene-containing vectors. A complete eradication of rAAV-2-EF1a-TK/eGFP (TK/enhanced green fluorescent protein fusion gene)-transduced tumor cells was shown following exposure to ganciclovir (2.5 mg/ml) in vitro, while at this dose level 490% of mock-transduced tumor cells survived. Xenotransplantation tumor models (intraperitoneal, subcutaneous) for the human sarcoma cell line HS-1 were established in nonobese diabetic/severe-combined immunodeficient mice. Mice transplanted with rAAV-2-EF1a-TK/eGFPtransduced and ganciclovir-exposed tumor cells survived 45 months while in the nontransduced group all mice had died approximately 1 month after inoculation. These data hold promise for further development of rAAV-2-based suicide gene therapy of sarcomas.

Susceptibility of mesothelioma cell lines to adeno-associated virus 2 vector-based suicide gene therapy

“…This might be the cause for the observed toxicity of the vector even without ganciclovir. Interestingly, using the same vector production system and virus stocks (partially), this toxicity was not observed in one of our previous studies [36], supporting the hypothesis, that this might be a virus-induced effect.…”

Generation of Rejuvenated Antigen-Specific T Cells by Reprogramming to Pluripotency and Redifferentiation

“…Therefore, the redifferentiation method will need to be further optimized and confirmed for clinical safety before application in practical treatments. This may be achieved by the use of an inducible suicide-gene system for eliminating unwanted tumors after injections (Hara et al, 2008;Veldwijk et al, 2004).…”

Treatment of human disease by adeno-associated viral gene transfer

“…Utilizing the well-characterized delivery of herpes simplex thymidine kinase gene (HSV-tk) followed by treatment with gancyclovir, AAV2-HSVtk gene delivery has proven effective in treating a variety of human tumor xenograft models including hepatoma, glioma, oral squamous carcinoma, and sarcoma (Berlinghoff et al 2004;Fukui et al 2001;Mizuno et al 1998;Okada et al 1996;Su et al 2000;Veldwijk et al 2004). These studies involved constitutive HSV-tk expression with ex vivo or intratumoral AAV-2 delivery to achieve selective transduction of tumor cells.…”