Synthesis and Evaluation of Technetium-99m- and Rhenium-Labeled Inhibitors of the Prostate-Specific Membrane Antigen (PSMA)
摘要:
The prostate- specific membrane antigen (PSMA) is increasingly recognized as a viable target for imaging and therapy of cancer. We prepared seven 99'Tc/Re-labeled compounds by attaching known Tc/Re chelating agents to an amino-functionalized PSMA inhibitor (lys-NHCONH-glu) with or without a variable length linker moiety. Ki values ranged from 0.17 to 199 nM. Ex vivo biodistribution and in vivo imaging demonstrated the degree of specific binding to engineered PSMA+ PC3 PIP tumors. PC3-PIP cells are derived from PO that have been transduced with the gene for PSMA. Despite demonstrating nearly the lowest PSMA inhibitory potency of this series, [99`Tc(COXLI)]+ (LI = (2-pyridylmethVI)2N(CH,,)4CH(COH)NHCO-(CH2)6CO-NH-lys-NHCONH-glu) showed the highest, most selective PIP tumor uptake, at 7.9 4.0% injected dose per gram of tissue at 30 min postinjection. Radioactivity cleared from nontarget tissues to produce a PIP to flu (PSMA-PC3) ratio of 44:1 at 120 min postinjection. PSMA can accommodate the steric requirements of 99"Tc/Re complexes within PSMA inhibitors, the best results achieved with a linker moiety between the e amine of the urea lysine and the chelator.
Synthesis and Evaluation of Technetium-99m- and Rhenium-Labeled Inhibitors of the Prostate-Specific Membrane Antigen (PSMA)
摘要:
The prostate- specific membrane antigen (PSMA) is increasingly recognized as a viable target for imaging and therapy of cancer. We prepared seven 99'Tc/Re-labeled compounds by attaching known Tc/Re chelating agents to an amino-functionalized PSMA inhibitor (lys-NHCONH-glu) with or without a variable length linker moiety. Ki values ranged from 0.17 to 199 nM. Ex vivo biodistribution and in vivo imaging demonstrated the degree of specific binding to engineered PSMA+ PC3 PIP tumors. PC3-PIP cells are derived from PO that have been transduced with the gene for PSMA. Despite demonstrating nearly the lowest PSMA inhibitory potency of this series, [99`Tc(COXLI)]+ (LI = (2-pyridylmethVI)2N(CH,,)4CH(COH)NHCO-(CH2)6CO-NH-lys-NHCONH-glu) showed the highest, most selective PIP tumor uptake, at 7.9 4.0% injected dose per gram of tissue at 30 min postinjection. Radioactivity cleared from nontarget tissues to produce a PIP to flu (PSMA-PC3) ratio of 44:1 at 120 min postinjection. PSMA can accommodate the steric requirements of 99"Tc/Re complexes within PSMA inhibitors, the best results achieved with a linker moiety between the e amine of the urea lysine and the chelator.
Prostate-specific membrane antigen (PSMA) targeting compounds are described. Uses of the compounds for imaging, therapy, cell sorting, and tumor mapping are also described.
[EN] PSMA-TARGETING COMPOUNDS AND USES THEREOF<br/>[FR] COMPOSÉS CIBLANT PSMA ET LEURS UTILISATIONS
申请人:UNIV JOHNS HOPKINS
公开号:WO2010108125A3
公开(公告)日:2011-03-24
<sup>68</sup>Ga-Labeled Inhibitors of Prostate-Specific Membrane Antigen (PSMA) for Imaging Prostate Cancer
作者:Sangeeta Ray Banerjee、Mrudula Pullambhatla、Youngjoo Byun、Sridhar Nimmagadda、Gilbert Green、James J. Fox、Andrew Horti、Ronnie C. Mease、Martin G. Pomper
DOI:10.1021/jm100623e
日期:2010.7.22
Gallium-68 is a generator-produced radionuclide for positron emission tomography (PET) that is being increasingly used for radiolabeling of tumor-targeting peptides. Compounds [Ga-68]3 and [Ga-68]6 are high-affinity urea-based inhibitors of the prostate-specific membrane antigen (PSMA) that were synthesized in decay-uncorrected yields ranging from 60% to 70% and radiochemical purities of more than 99%. Compound [Ga-68]3 demonstrated 3.78 +/- 0.90% injected dose per gram of tissue (%ID/g) within PSMA + PIP tumor at 30 min postinjection, while [Ga-68]6 showed a 2 h PSMA + PIP tumor uptake value of 3.29 +/- 0.77 %ID/g. Target (PSMA + PIP) to nontarget (PSMA - flu) ratios were 4.6 and 18.3, respectively, at those time points. Both compounds delineated tumor clearly by small animal PET. The urea series of imaging agents for PSMA can be radiolabeled with Ga-68, a cyclotron-free isotope useful for clinical PET studies, with maintenance of target specificity.
Urea-based peptide compounds useful for detecting inter alia prostate cancer