A Flexible Synthesis of 68Ga-Labeled Carbonic Anhydrase IX (CAIX)-Targeted Molecules via CBT/1,2-Aminothiol Click Reaction

We herein describe a flexible synthesis of a small library of 68Ga-labeled CAIX-targeted molecules via an orthogonal 2-cyanobenzothiazole (CBT)/1,2-aminothiol click reaction. Three novel CBT-functionalized chelators (1–3) were successfully synthesized and labeled with the positron emitter gallium-68. Cross-ligation between the pre-labeled bifunctional chelators (BFCs) and the 1,2-aminothiol-acetazolamide derivatives (8 and 9) yielded six new 68Ga-labeled CAIX ligands with high radiochemical yields. The click reaction conditions were optimized to improve the reaction rate for applications with short half-life radionuclides. Overall, our methodology allows for a simple and efficient radiosynthetic route to produce a variety of 68Ga-labeled imaging agents for tumor hypoxia.

[1]  G. Liang,et al.  Applications of CBT-Cys click reaction: past, present, and future , 2018, Science China Chemistry.

[2]  Allen F. Brooks,et al.  Gallium-68: methodology and novel radiotracers for positron emission tomography (2012-2017). , 2018, Pharmaceutical patent analyst.

[3]  Y. Seimbille,et al.  Two bifunctional desferrioxamine chelators for bioorthogonal labeling of biovectors with zirconium-89. , 2018, Organic & biomolecular chemistry.

[4]  Y. Seimbille,et al.  Early‐Stage Incorporation Strategy for Regioselective Labeling of Peptides using the 2‐Cyanobenzothiazole/1,2‐Aminothiol Bioorthogonal Click Reaction , 2018, ChemistryOpen.

[5]  M. Bartholomä,et al.  Gallium Complexation, Stability, and Bioconjugation of 1,4,7-Triazacyclononane Derived Chelators with Azaheterocyclic Arms. , 2017, Inorganic chemistry.

[6]  F. Bénard,et al.  Design, synthesis and evaluation of 18F-labeled cationic carbonic anhydrase IX inhibitors for PET imaging , 2017, Journal of enzyme inhibition and medicinal chemistry.

[7]  P. Lambin,et al.  Synthesis and in Vivo Biological Evaluation of (68)Ga-Labeled Carbonic Anhydrase IX Targeting Small Molecules for Positron Emission Tomography. , 2016, Journal of medicinal chemistry.

[8]  D. Neri,et al.  A 99mTc-Labeled Ligand of Carbonic Anhydrase IX Selectively Targets Renal Cell Carcinoma In Vivo , 2016, The Journal of Nuclear Medicine.

[9]  W. Breeman,et al.  Radiolabeling of DOTA-like conjugated peptides with generator-produced 68Ga and using NaCl-based cationic elution method , 2016, Nature Protocols.

[10]  F. Bénard,et al.  PET Imaging of Carbonic Anhydrase IX Expression of HT-29 Tumor Xenograft Mice with (68)Ga-Labeled Benzenesulfonamides. , 2016, Molecular pharmaceutics.

[11]  L. Carroll,et al.  Bioorthogonal chemistry for (68) Ga radiolabelling of DOTA-containing compounds. , 2014, Journal of labelled compounds & radiopharmaceuticals.

[12]  F. Bénard,et al.  Synthesis and evaluation of 18F-labeled carbonic anhydrase IX inhibitors for imaging with positron emission tomography , 2014, Journal of enzyme inhibition and medicinal chemistry.

[13]  I. Velikyan Prospective of 68Ga-Radiopharmaceutical Development , 2013, Theranostics.

[14]  J. Pastorek,et al.  Carbonic anhydrase IX, a hypoxia-induced catalytic component of the pH regulating machinery in tumors , 2013, Front. Physiol..

[15]  S. Yao,et al.  Site-specific immobilization of biomolecules by a biocompatible reaction between terminal cysteine and 2-cyanobenzothiazole. , 2013, Chemical communications.

[16]  J. Rao,et al.  Efficient method for site-specific 18F-labeling of biomolecules using the rapid condensation reaction between 2-cyanobenzothiazole and cysteine. , 2012, Bioconjugate chemistry.

[17]  Claudiu T. Supuran,et al.  Recent Developments in Targeting Carbonic Anhydrase IX for Cancer Therapeutics , 2012, Oncotarget.

[18]  J. Šimeček,et al.  TRAP, a powerful and versatile framework for gallium-68 radiopharmaceuticals. , 2011, Chemistry.

[19]  H. Moch,et al.  Overexpression of carbonic anhydrase IX (CAIX) is an independent unfavorable prognostic marker in endometrioid ovarian cancer , 2011, Virchows Archiv.

[20]  W. Wilson,et al.  Targeting hypoxia in cancer therapy , 2011, Nature Reviews Cancer.

[21]  S. Leung,et al.  Targeting tumor hypoxia: suppression of breast tumor growth and metastasis by novel carbonic anhydrase IX inhibitors. , 2011, Cancer research.

[22]  A. Harris,et al.  New insights into the physiological role of carbonic anhydrase IX in tumour pH regulation , 2010, Oncogene.

[23]  É. Tóth,et al.  Gallium(III) complexes of DOTA and DOTA-monoamide: kinetic and thermodynamic studies. , 2010, Inorganic chemistry.

[24]  Xiaoyuan Chen,et al.  Design and development of molecular imaging probes. , 2010, Current topics in medicinal chemistry.

[25]  J. Pouysségur,et al.  High levels of carbonic anhydrase IX in tumour tissue and plasma are biomarkers of poor prognostic in patients with non-small cell lung cancer , 2010, British Journal of Cancer.

[26]  A. Belldegrun,et al.  Carbonic anhydrase IX in bladder cancer , 2009, Cancer.

[27]  J. Leppert,et al.  236: Carbonic Anhydrase IX (CAIX) in Bladder Cancer: A Diagnostic, Prognostic and Therapeutic Molecular Marker , 2007 .

[28]  E. Stanbridge,et al.  Identification of the MN/CA9 protein as a reliable diagnostic biomarker of clear cell carcinoma of the kidney. , 1997, Cancer research.

[29]  A. Martell,et al.  STABILITIES OF THE FE(III), GA(III) AND IN(III) CHELATES OF N,N',N''-TRIAZACYCLONONANETRIACETIC ACID , 1991 .

[30]  J. Erler,et al.  Hypoxia-mediated metastasis. , 2014, Advances in experimental medicine and biology.

[31]  I. Velikyan Prospective of 68 Ga-Radiopharmaceutical Development , 2014 .

[32]  J. Rao,et al.  A biocompatible condensation reaction for the labeling of terminal cysteine residues on proteins. , 2009, Angewandte Chemie.