Donor lymphocytes expressing the herpes simplex virus thymidine kinase suicide gene: detailed immunological function following add-back after haplo-identical transplantation

Lentivirus-mediated CDglyTK gene-modified free flaps by intra-artery perfusion show targeted therapeutic efficacy in rat model of breast cancer

Background

Free flap-mediated gene therapy in the tumor bed following surgical resection is a promising approach in cancer targeted treatment of residual disease. We investigated the selective killing efficacy of a lentivirus-mediated cytosine deaminase-thymidine kinase (CDglyTK) gene in transplanted breast cancer delivered into a free flap by intra-artery perfusion.

Methods

Proliferation, apoptosis, and cell cycle of rat SHZ-88 breast cancer cells transfected with a lentivirus-mediated CD/TK gene were measured following treatment with ganciclovir and 5-flucytosine in vitro. A model of residual disease of breast cancer in a rat superficial inferior epigastric artery (SIEA) flap model was used to study the therapeutic potential of a double suicide CD/TK and prodrug system in vivo.

Results

Killing efficacy of the double suicide CD/TK and prodrug system on SHZ-88 cells was mediated by increased apoptosis and cell cycle arrest at the G1 phase with significant bystander effect. Following recombinant lentivirus transfection of rat SIEA flap by intra-artery perfusion, CD/TK gene expression was limited to the flap, and the volume and weight of transplanted tumors were significantly reduced without observable toxicity.

Conclusions

SIEA flaps transfected with a lentivirus-mediated CDglyTK gene by intra-artery perfusion effectively suppress transplanted breast tumor growth without obvious systemic toxic effects in rats.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-6111-5) contains supplementary material, which is available to authorized users.

Current status of ex vivo gene therapy for hematological disorders: a review of clinical trials in Japan around the world

Gene therapies are classified into two major categories, namely, in vivo and ex vivo. Clinical trials of human gene therapy began with the ex vivo techniques. Based on the initial successes of gene-therapy clinical trials, these approaches have spread worldwide. The number of gene therapy trials approved worldwide increased gradually starting in 1989, reaching 116 protocols per year in 1999, and a total of 2210 protocols had been approved by 2015. Accumulating clinical evidence has demonstrated the safety and benefits of several types of gene therapy, with the exception of serious adverse events in several clinical trials. These painful experiences were translated backward to basic science, resulting in the development of several new technologies that have influenced the recent development of ex vivo gene therapy in this field. To date, six gene therapies have been approved in a limited number of countries worldwide. In Japan, clinical trials of gene therapy have developed under the strong influence of trials in the US and Europe. Since the initial stages, 50 clinical trials have been approved by the Japanese government. In this review, the history and current status of clinical trials of ex vivo gene therapy for hematological disorders are introduced and discussed.