In Vivo Quantitative Imaging of Glioma Heterogeneity Employing Positron Emission Tomography

Cranial imaging window implantation technique for longitudinal multimodal imaging of the brain environment in live mice

Intravital two-photon microscopy of the mouse brain requires visual access without affecting normal cognitive functions, which is crucial for longitudinal imaging studies that may last several months. In this protocol, we describe the surgical implantation of a metal-free cranial imaging window, which can be used to perform two-photon microscopy and magnetic resonance imaging in the same animal. This multimodal imaging platform enables the investigation of dynamic processes in the central nervous system at a cellular and macroscopic level. For complete details on the use and execution of this protocol in the context of brain cancer, please refer to Zomer et al.¹.

Multi-Targeted Neutron Capture Therapy Combined with an 18 kDa Translocator Protein-Targeted Boron Compound Is an Effective Strategy in a Rat Brain Tumor Model

BACKGROUND

Boron neutron capture therapy (BNCT) has been adapted to high-grade gliomas (HG); however, some gliomas are refractory to BNCT using boronophenylalanine (BPA). In this study, the feasibility of BNCT targeting the 18 kDa translocator protein (TSPO) expressed in glioblastoma and surrounding environmental cells was investigated.

METHODS

Three rat glioma cell lines, an F98 rat glioma bearing brain tumor model, DPA-BSTPG which is a boron-10 compound targeting TSPO, BPA, and sodium borocaptate (BSH) were used. TSPO expression was evaluated in the F98 rat glioma model. Boron uptake was assessed in three rat glioma cell lines and in the F98 rat glioma model. In vitro and in vivo neutron irradiation experiments were performed.

RESULTS

DPA-BSTPG was efficiently taken up in vitro. The brain tumor has 16-fold higher TSPO expressions than its brain tissue. The compound biological effectiveness value of DPA-BSTPG was 8.43 to F98 rat glioma cells. The boron concentration in the tumor using DPA-BSTPG convection-enhanced delivery (CED) administration was approximately twice as high as using BPA intravenous administration. BNCT using DPA-BSTPG has significant efficacy over the untreated group. BNCT using a combination of BPA and DPA-BSTPG gained significantly longer survival times than using BPA alone.

CONCLUSION

DPA-BSTPG in combination with BPA may provide the multi-targeted neutron capture therapy against HG.