The pronounced dependence of the iRGD-induced AFP transport on the basal blood concentration in all tested HCC mouse models suggests that this transport strongly depends on the concentration gradient of the substance to be transported between the tumour and the blood, a trait that also holds for VEGF-A-induced vascular leakage, which is also mediated by NRP-1.45 Here, NRP1 is linked to hepatocellular carcinoma.