IGFBP7 and glioblastoma: Systemic injection of anti-IGFBP7 nanobody conjugated to Fe3O4 PEGylated Cy5.5-labeled nanoparticles led to higher rates of average fluorescence concentration in the orthotopic implanted GBM region in vivo, in comparison with Cy5.5-labeled anti-IGFBP7 nanobody [66].