Theranostic techniques based on PSMA in prostate cancer

Background: Many efforts have been done in order to discovery new manners of radiopharmaceuticals, for diagnostic and therapeutic purposes in prostate cancer (PCa). In pursuit of such a goal widespread categories of monoclonal antibodies (mAb) used since at least 20 years ago. Pros and cons of these radiolabeled tracers investigated in clinical trials. Recent trends towards the prostate specific membrane antigen (PSMA) based radiopharmaceuticals known as low molecular weight (LMW) inhibitors, opened new horizon in clinical trials. The aim of this study is to compare pharmacological and chemical structural modification effects on PCa specific radiotracers during the development period.Results: 111In-Capromab (prostascint®) the first FDA approved mAb used as a radiotracer of PCa with clinical application of presurgical staging and PSA relapse. Even though the mAb was efficient, clinical trials didn’t approve this agent as a continuous method of imaging. Generally, it refers to the internalization mechanism of Capromab, that because of internal interaction between mAb and PSMA, just dead and lysed cells are recognized. So many trials have been done to extend mAbs with external internalization mechanism, include 3/F11, 7/E11, 3/E7, 3/A12, 3C6, J415, J533 and J591. Among these series J591 put forward as an appropriate mAb for radiolabeling. Clinical trials indicated different results with various radionuclides in radiolabeling. Eventually, LMW inhibitors with improved pharmacokinetic specifications were raised. Urea based PSMA ligands, MIP-1072/-1095, MIP-1404/-1405, HBED-PSMA, PSMA-1007, PSMA-I&T, DCFBC and DCFPyl were the most important inhibitors in PCa. Among the extensive radionuclides used as imaging and therapy with α-, β- and γ emotions, 68Ga-PSMA-11 and 177Lu-PSMA-617 for the aim if diagnostic and therapy are authorized with significant optimistic results.Conclusion: Researches demonstrates high detection and therapy results by 68Ga-PSMA-11 and 177Lu-PSMA-617. Significant chemical stability, improved pharmacokinetic, increased accumulation of tracer in tumor to non-target tissues resulted from faster blood clearance compared with other tracers were all worthy points of these two radio-tracers.

کلیدواژه ها:

Theranostic ، radionuclide therapy ، PSMA ، mCRPC