Schottelius, M.* ; Wurzer, A.* ; Wissmiller, K.* ; Beck, R.* ; Koch, M. ; Gorpas, D. ; Notni, J.* ; Buckle, T.* ; van Oosterom, M.N.* ; Steiger, K.* ; Ntziachristos, V. ; Schwaiger, M.* ; van Leeuwen, F.W.B.* ; Wester, H.J.*
Synthesis and preclinical characterization of the PSMA-targeted hybrid tracer PSMA-I&F for nuclear and fluorescence imaging of prostate cancer.
J. Nucl. Med. 60, 71-78 (2018)
The prostate-specific membrane antigen (PSMA)-targeted radiotracers Ga-68/Lu-177-PSMA-I&T and Tc-99m-PSMA-I&S (for imaging and surgery) are currently successfully used for clinical PET imaging, radionuclide therapy, and radioguided surgery of metastatic prostate cancer. To additionally exploit the high sensitivity and spatial resolution of fluorescence imaging for improved surgical guidance, a PSMA-I&T-based hybrid tracer, PSMA-I&F (DOTAGA-k(Sulfo-Cy5)-y-nal-k-Sub-KuE), has been developed and evaluated. Methods: The in vitro PSMA-targeting efficiency of PSMA-I&F, the reference PSMA-I&T, and their corresponding Ga-nat-/Ga-68- and Lu-nat/Lu-177 counterparts was determined in LNCaP cells via competitive binding assays (IC50) and dual-tracer radioligand and fluorescence internalization studies. Biodistribution and small-animal PET imaging studies were performed in CB17 SCID and LNCaP xenograft-bearing SHO mice, respectively, and complemented by intraoperative far-red fluorescence imaging using a clinical laparoscope. Additionally, fully automated serial cryosectioning and fluorescence imaging of 1 tumor-bearing animal as well as PSMA immunohistochemistry and fluorescence microscopy of organ cryosections (tumor, kidney, spleen) were also performed. Results: Compared with the parent PSMA-I&T analogs, the PSMA affinities of PSMA-I&F and its Ga-nat-/Lu-nat-complexes remained high and unaffected by dye conjugation (7.9 < IC50 < 10.5 nM for all ligands). The same was observed for the internalization of Ga-68- and Lu-177-PSMA-I&F. In vivo, blood clearance of Ga-68- and Lu-177-PSMA-I&F was only slightly delayed by high plasma protein binding (94%-95%), and very low accumulation in nontarget organs was observed already at 1 h after injection. Dynamic PET imaging confirmed PSMA-specific (as demonstrated by coinjection of 2-PMPA) uptake into the LNCaP xenograft (4.5% +/- 1.8 percentage injected dose per gram) and the kidneys (106% +/- 23 percentage injected dose per gram). Tumor-to-background ratios of 2.1, 5.2, 9.6, and 9.6 for blood, liver, intestines, and muscle, respectively, at 1 h after injection led to excellent imaging contrast in Ga-68-PSMA-I&F PET and in intraoperative fluorescence imaging. Furthermore, fluorescence imaging of tissue cryosections allowed high-resolution visualization of intraorgan PSMA-I&F distribution in vivo and its correlation with PSMA expression as determined by immunohistochemistry. Conclusion: Thus, with its high PSMA-targeting efficiency and favorable pharmacokinetic profile, Ga-68/Lu-177-PSMA-I&F serves as an excellent proof-of-concept compound for the general feasibility of PSMA-I&T-based hybrid imaging. The PSMA-I&T scaffold represents a versatile PSMA-targeted lead structure, allowing relatively straightforward adaptation to the different structural requirements of dedicated nuclear or hybrid imaging agents.
Impact Factor
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Publikationstyp
Artikel: Journalartikel
Dokumenttyp
Wissenschaftlicher Artikel
Typ der Hochschulschrift
Herausgeber
Schlagwörter
Psma ; Prostate Cancer ; Fluorescence ; Hybrid Tracer ; Intraoperative Guidance; Dual-modality; Guided Surgery; Radioguided Surgery; Surgical Guidance; Ligands; Agents; Therapy; Optimization; Radionuclide; Inhibitor
Keywords plus
Sprache
englisch
Veröffentlichungsjahr
2018
Prepublished im Jahr
HGF-Berichtsjahr
2018
ISSN (print) / ISBN
0161-5505
e-ISSN
1535-5667
ISBN
Bandtitel
Konferenztitel
Konferzenzdatum
Konferenzort
Konferenzband
Quellenangaben
Band: 60,
Heft: 1,
Seiten: 71-78
Artikelnummer: ,
Supplement: ,
Reihe
Verlag
Society of Nuclear Medicine and Molecular Imaging
Verlagsort
1850 Samuel Morse Dr, Reston, Va 20190-5316 Usa
Tag d. mündl. Prüfung
0000-00-00
Betreuer
Gutachter
Prüfer
Topic
Hochschule
Hochschulort
Fakultät
Veröffentlichungsdatum
0000-00-00
Anmeldedatum
0000-00-00
Anmelder/Inhaber
weitere Inhaber
Anmeldeland
Priorität
Begutachtungsstatus
Peer reviewed
POF Topic(s)
30205 - Bioengineering and Digital Health
Forschungsfeld(er)
Enabling and Novel Technologies
PSP-Element(e)
G-505500-001
Förderungen
Copyright
Erfassungsdatum
2018-10-29