Selective delivery of herpes virus vectors to experimental brain tumors using RMP-7

Area of Science:

• Oncology
• Virology
• Pharmacology

Background:

• RMP-7, a bradykinin analog, selectively opens the blood-tumor barrier for chemotherapy delivery.
• RMP-7 is approved for human use and lacks hypotensive effects.
• Virus vectors offer a promising approach for brain tumor gene therapy.

Purpose of the Study:

• To evaluate RMP-7's efficacy in enhancing the delivery of virus vectors to brain tumors.
• To assess the safety and specificity of RMP-7 mediated viral delivery.

Main Methods:

• An experimental rat model with intracranial 9L gliosarcomas was used.
• The herpes virus vector hrR3, encoding thymidine kinase and lacZ, was employed.
• RMP-7 was administered via carotid artery infusion prior to virus vector delivery.

Main Results:

• An optimal RMP-7 dose (1.5-3.0 microg/kg) significantly enhanced viral delivery to brain tumors.
• Maximum lacZ reporter gene expression was observed at 3 days post-infusion.
• Viral delivery was specific to tumor cells with minimal off-target effects in healthy brain tissue or organs.

Conclusions:

• Intracarotid RMP-7 delivery augments selective virus vector targeting to brain tumors in a rat model.
• This strategy holds potential for improving gene therapy delivery to human brain tumors.
• RMP-7 facilitates targeted delivery of therapeutic genes via viral vectors to gliosarcomas.