Molecular imaging-guided gene therapy of experimental gliomas

Background: The combination of transgenes encoding prodrug-activating enzymes serves synergistic anti-tumor activity (e.g. E. coli cytosine deaminase (cd) and HSV-1 thymidine kinase (tk)). We used positron emission tomography (PET) and magnetic resonance imaging (MRI) for imaging-guided targeted application of universal HSV-1 amplicon vectors and assessment of therapeutic efficiency. Methods: Human Gli36dEGFR glioma cells were grown as s.c. tumors in 22 nude mice and transduced in vivo with HSV-1 amplicons carrying cd, HSV-1-tk39 and gfp (HSV-cdIREStk39gfp). Non-transduced tumors served as negative controls, sta…