Development of Bispecific NT-PSMA Heterodimer for Prostate Cancer Imaging: A Potential Approach to Address Tumor...

Area of Science:

• Oncology
• Radiochemistry
• Molecular Imaging

Background:

• Prostate cancer is a heterogeneous disease with limited late-stage survival rates.
• Tumor heterogeneity poses challenges for effective diagnosis and treatment.
• Prostate-specific membrane antigen (PSMA) and neurotensin receptor 1 (NTR1) are key targets in prostate cancer management.

Purpose of the Study:

• To develop a dual-targeting positron emission tomography (PET) agent to address prostate cancer heterogeneity.
• To create a heterodimer agent, F-BCN-PSMA-NT, targeting both PSMA and NTR1.
• To evaluate the diagnostic and potential therapeutic applications of this novel agent.

Main Methods:

• Synthesis of the heterodimer F-BCN-PSMA-NT by conjugating PSMA and NTR1 targeting motifs to a trifunctional linker.
• Radio-labeling using strain-promoted azide-alkyne click chemistry.
• In vitro cell-based assays to assess binding affinity.
• Small animal PET imaging to evaluate in vivo tumor uptake and targeting efficacy.

Main Results:

• The heterodimer F-BCN-PSMA-NT demonstrated comparable or slightly reduced binding affinity to monomers.
• PET imaging showed significant uptake in both NTR1-positive/PSMA-negative (PC-3) and PSMA-positive/NTR1-negative (LnCap) tumors.
• The dual-targeting tracer achieved tumor-to-background ratios similar to individual targeting agents.

Conclusions:

• The PSMA-NT heterodimer represents a new class of molecules for targeting distinct prostate cancer antigens.
• This dual-targeting agent effectively images heterogeneous prostate cancer, addressing limitations of single-target agents.
• The F-BCN-PSMA-NT agent holds significant potential for both advanced imaging and treatment of heterogeneous prostate cancer.