APLN and neoplasm: Injection of U87NSC into APLNKO mice (U87NSCAPLNKO) resulted in a VLD of 2601 mm/mm3, whereas combined ablation of APLN expression in U87MG cells and in the host (implantation of U87AKD cells into immune-deficient APLNKO mice; U87AKDAPLNKO) largely blocked tumor angiogenesis and resulted in a VLD of 766 mm/mm3, which is lower than in tumor-free brain-tissue (Figure 2C and Figure 3B).