Department of Radiological Sciences, Oncology and Anatomo-Pathology, Sapienza, University of Rome, Rome, Italy.
Department of Nuclear Medicine, Santa Maria Goretti Hospital, Latina, Italy.
Expert Rev Mol Diagn. 2022 Nov;22(11):991-996. doi: 10.1080/14737159.2022.2145187. Epub 2022 Nov 11.
Prostate and breast cancer represent a leading cause of cancer-related death worldwide with a dramatic social and demographic impact. Gastrin-releasing peptide receptors (GRPRs), part of the bombesin (BBN) family, have been found overexpressed in both the aforementioned malignancies, and have emerged as a potentially useful target to combine imaging and therapy in a unique, synergistic approach, namely 'theranostics.'
The biological characteristics of GRPRs, as well as their aberrant expression in breast and prostate cancer, are covered. Furthermore, the role of the different available GRPR agonists and antagonists, labeled with radionuclides suitable for molecular imaging through single photon computed tomography (SPECT) or positron emission computed (PET/CT), is reviewed, with a particular focus on the potential theranostic implications.
GRPR-targeted molecular imaging of breast and prostate cancer gave promising results in pre-clinical studies. Notably, GRPRs' expression was found to be inversely correlated with disease progression in both prostate and breast cancer. Among the different GRPR agonists and antagonists applied as imaging probes, RM26 presented particularly interesting applications, with meaningful theranostic potential, but its diagnostic performance resulted highly influenced by the choice of the chelator-radionuclide complex, being long-life radionuclides more suitable for obtaining high-contrast imaging.
前列腺癌和乳腺癌是全球癌症相关死亡的主要原因，对社会和人口结构具有重大影响。胃泌素释放肽受体（GRPR）是蛙皮素（BBN）家族的一部分，在上述两种恶性肿瘤中均过度表达，并已成为一种潜在有用的靶点，可以通过独特的协同方法将成像和治疗结合起来，即“治疗诊断学”。
介绍了 GRPR 的生物学特性，以及它们在乳腺癌和前列腺癌中的异常表达。此外，还回顾了不同可用的 GRPR 激动剂和拮抗剂的作用，这些激动剂和拮抗剂与适合通过单光子发射计算机断层扫描（SPECT）或正电子发射计算机断层扫描（PET/CT）进行分子成像的放射性核素标记，特别关注潜在的治疗诊断意义。
GRPR 靶向的乳腺癌和前列腺癌分子成像在临床前研究中取得了有希望的结果。值得注意的是，在前列腺癌和乳腺癌中，GRPR 的表达与疾病进展呈负相关。在用作成像探针的不同 GRPR 激动剂和拮抗剂中，RM26 具有特别有趣的应用，具有有意义的治疗诊断潜力，但它的诊断性能受到螯合剂-放射性核素复合物选择的极大影响，长寿命放射性核素更适合获得高对比度成像。
