Development of Integrin α5β1-targeted PET/NIR imaging probes for glioblastoma intraoperative navigation and intracavity targeted radionuclide therapy

Incomplete extent of tumor resection is the major factor of glioblastoma recurrence, leading to its poor prognosis. Developing therapies that enable the minimal tumor cell remnant during surgical resection is a major challenge to combat this aggressive cancer. This study develops a glioblastoma integrin 5{beta}1-selective peptide binder through series strategy screening and labeling it with 68Ga, indocyanine green (ICG), or 177Lu for efficacious multimodal treatment. This strategy combines positron emission tomography (PET) imaging for preoperative diagnosis, intraoperative NIR-II fluorescence-guided surgery for maximal tumor resection, and followed by intracavity targeted radionuclide therapy for elimination of residual tumor cells. We identified GR, with five arginine mutation, exhibiting superior integrin 5{beta}1 binding affinity and brain penetration. [68Ga]GR demonstrated substantial tumor uptake and prolonged retention time in both mouse models and tissues from glioblastoma patients. The guidance of ICG-GR achieved accurately intraoperative tumor imaging and maximal tumor resection in orthotopic mouse glioblastoma models. Notably, combining intracavity administration of [177Lu]GR following ICG-GR guiding resection markedly inhibited tumor growth and reduced possibility of tumor recurrence compared with surgery alone (unguided or ICG-GR-guided) or unguided surgery followed by [177Lu]GR. Therefore, we have reported the integrin 5{beta}1-targeted radionuclide and optical agents for maximal elimination of tumor cells during surgical resection in glioblastoma patients. HIGHLIGHTSO_LIGR is a glioblastoma-specific peptide with both favorable binding affinity superior brain penetration. C_LIO_LIICG-GR is a glioblastoma-targeted NIR probe enabling maximal surgical resection. C_LIO_LIICG-GR-guided surgery with [177Lu]GR-based adjuvant therapy allows robust elimination of tumor cells. C_LI