Using quantitative RT-PCR, it was demonstrated that rLAS-uPA was able to persistently colonize a subset of uPAR-expressing canine intracranial tumors following intravenous administration, including meningiomas, oligodendrogliomas, and choroid plexus tumors, which represent the most common primary brain tumors in dogs [1,5]. This evidence concerns the gene PLAU and brain neoplasm.