Preliminary Evaluation of Prostate Cancer Molecular Probe ⁶⁸Ga-DOTA-ANCP-PSMA

Prostate cancer is the most common malignant tumor in males with high mortality. The mortality rate is over 11%. Prostate specific membrane antigen(PSMA) is an ideal target for prostate cancer diagnosis. Using positron emitter 68Ga labeled PSMA small molecule inhibitors for prostate cancer diagnosis, staging and efficacy evaluation has become a world-wide focus. In order to develop a new 68Ga labeled PSMA probe with better properties both in vitro and in vivo, a novel PSMA small molecule inhibitor ⁶⁸Ga-DOTA-ANCP-PSMA was designed. The precursor compound was synthesized by peptide solid phase synthesis. ⁶⁸Ga was labeled to the PSMA probe directly. The labeled compound properties both in vitro and in vivo were measured. The purified labeled compound shows good stability in vitro. Radiochemical purity can be stable in PBS and BSA system for 2 hours. The octanol-water partition coefficient is -1.42. Biological distribution studies show fast blood clearance, low liver uptake, and renal metabolism. There are low uptake in non-target organs such as the heart, lung and spleen. Bladder shows a high uptake, because the labeled compound mainly excrets through urine. Tumor shows high uptake. In the PET-CT imaging study, ⁶⁸Ga-DOTA-ANCP-PSMA is clear imaging in tumor, also shows good sensitivity and specificity in PET-CT block study. This compound has good properties in vitro and in vivo. It may have good research and development prospect for prostate cancer diagnosis.