Sonodynamic therapy for treatment of C6 glioma in a rat model step 1: feasibility of tumor model

Gliomas represent the most common and devastating primary CNS tumor. While surgical resection is the mainstay of treatment, treating physicians are seeking a safer and more effective treatment modality that is non-invasive, deep-penetrating, and less prone to infection and damage to surrounding tissues. Photodynamic therapy, utilizing a photosensitizing agent with laser light, while effective in a variety of solid tissue tumors, has not proven to be especially advantageous in the treatment of gliomas, due to the poor penetration of the light. Sonodynamic therapy has been explored as an alternative to PDT. Sensitizers such as 5-aminolevulinic acid (5-ALA) and indocyanine green (IcG) have been shown to be preferentially taken up by glioma cells. Low-intensity ultrasound waves can provide enough energy to activate sensitizing agents and induce apoptosis, without the collateral damage to surrounding tissues seen with laser light in PDT. The aim of this initial study is to determine whether the sonosensitizers 5-ALA and IcG can be effectively delivered to, and detected in, the subcutaneous C6 glioma rat model.