Radioiodinated Peptidic Imaging Probes for in Vivo Detection of Membrane Type-1 Matrix Metalloproteinase in Cancers.

摘要: Membrane type-1 matrix metalloproteinase (MT1-MMP) plays pivotal roles in tumor progression and metastasis, holds great promise as an early biomarker for malignant tumors. Therefore, the ability to evaluate MT1-MMP expression could be valuable molecular biological clinical studies. For this purpose, we aimed develop short peptide-based nuclear probes because of their facile radiosynthesis, chemically uniform structures, high specific activity, compared antibody-based probes, which allow them more effective vivo imaging. To best our knowledge, there have been no reports radiolabeled peptide detection cancer tissues. In study, designed prepared four consist a MT1-MMP-specific binding sequence (consisting L or D amino acid isomers) additional cysteine (at N C-terminus) conjugation with N-(m-[(123/125)I]iodophenyl) maleimide. We investigated probe affinity, stability mice plasma, biodistribution tumor-bearing mice. Finally, micro single photon emission computed tomography (SPECT) imaging ex autoradiography were performed. Consequently, [(123)I]I-DC, D-form radioiodinated at C-terminus, demonstrated greater than 1000-fold higher activity previously reported antibody revealed comparably moderate affinity. [(125)I]I-DC showed expected, [(123)I]I-DC successfully identified expressing tissue by SPECT Furthermore, autoradiographic analysis that radioactivity distribution profiles corresponded MT1-MMP-positive areas. These findings suggest is promising cancers.