The statistically significant decrease in the Ktrans of the BBTB of both anterior and posterior gliomas with labradimil infusion that we observed would be attributable to the combination of: (1) the greater metabolic stability than Met-Lys-BK that resulted in a more significant fall in MABP as compared to that caused by Met-Lys-BK infusion, and (2) a lower affinity than Met-Lys-BK for the bradykinin B2 receptors over-expressed on tumor microvasculature. This evidence concerns the gene KNG1 and central nervous system cancer.