Early response measurements of NGR-TNF efficacy using MR and immunohistochemical methods
Gambarota G, van Laarhoven H, Lok J, Punt C, Corti A, Verhagen I, van der Kogel A, Heerschap A, Stampino C, Toma S
University Medical Centre Nijmegen
Targeted delivery to the tumor of picogram doses of TNF- can be achieved by coupling TNF- with CNGRC (NGR-TNF), a peptide that targets tumor neovasculature. We assessed NGR-TNF efficacy at an early stage in lymphoma bearing mice. MRI measurements with blood pool contrast agent showed an increased leakage of contrast agent from the vasculature in NGR-TNF treated tumors compared with controls, suggesting NGR-TNF-induced vascular permeability. Immunohistochemical analysis showed a decrease in tumor hypoxia and an increase in labeling index of the S-phase marker bromodeoxyuridine, possibly due to an increase in tumor blood flow after NGR-TNF treatment.