1
|
Lawal IO, Abubakar SO, Ndlovu H, Mokoala KMG, More SS, Sathekge MM. Advances in Radioligand Theranostics in Oncology. Mol Diagn Ther 2024; 28:265-289. [PMID: 38555542 DOI: 10.1007/s40291-024-00702-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/06/2024] [Indexed: 04/02/2024]
Abstract
Theranostics with radioligands (radiotheranostics) has played a pivotal role in oncology. Radiotheranostics explores the molecular targets expressed on tumor cells to target them for imaging and therapy. In this way, radiotheranostics entails non-invasive demonstration of the in vivo expression of a molecular target of interest through imaging followed by the administration of therapeutic radioligand targeting the tumor-expressed molecular target. Therefore, radiotheranostics ensures that only patients with a high likelihood of response are treated with a particular radiotheranostic agent, ensuring the delivery of personalized care to cancer patients. Within the last decades, a couple of radiotheranostics agents, including Lutetium-177 DOTATATE (177Lu-DOTATATE) and Lutetium-177 prostate-specific membrane antigen (177Lu-PSMA), were shown to prolong the survival of cancer patients compared to the current standard of care leading to the regulatory approval of these agents for routine use in oncology care. This recent string of successful approvals has broadened the interest in the development of different radiotheranostic agents and their investigation for clinical translation. In this work, we present an updated appraisal of the literature, reviewing the recent advances in the use of established radiotheranostic agents such as radioiodine for differentiated thyroid carcinoma and Iodine-131-labeled meta-iodobenzylguanidine therapy of tumors of the sympathoadrenal axis as well as the recently approved 177Lu-DOTATATE and 177Lu-PSMA for differentiated neuroendocrine tumors and advanced prostate cancer, respectively. We also discuss the radiotheranostic agents that have been comprehensively characterized in preclinical studies and have shown some clinical evidence supporting their safety and efficacy, especially those targeting fibroblast activation protein (FAP) and chemokine receptor 4 (CXCR4) and those still being investigated in preclinical studies such as those targeting poly (ADP-ribose) polymerase (PARP) and epidermal growth factor receptor 2.
Collapse
Affiliation(s)
- Ismaheel O Lawal
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology and Imaging Sciences, Emory University, 1364 Clifton Road, NE, Atlanta, GA, 30322, USA.
- Department of Nuclear Medicine, University of Pretoria, Pretoria, 0001, South Africa.
| | - Sofiullah O Abubakar
- Department of Radiology and Nuclear Medicine, Sultan Qaboos Comprehensive Cancer Care and Research Center, Muscat, Oman
| | - Honest Ndlovu
- Department of Nuclear Medicine, University of Pretoria, Pretoria, 0001, South Africa
- Nuclear Medicine Research Infrastructure (NuMeRI), Steve Biko Academic Hospital, Pretoria, 0001, South Africa
| | - Kgomotso M G Mokoala
- Department of Nuclear Medicine, University of Pretoria, Pretoria, 0001, South Africa
- Nuclear Medicine Research Infrastructure (NuMeRI), Steve Biko Academic Hospital, Pretoria, 0001, South Africa
| | - Stuart S More
- Department of Nuclear Medicine, University of Pretoria, Pretoria, 0001, South Africa
- Division of Nuclear Medicine, Department of Radiation Medicine, University of Cape Town, Cape Town, 7700, South Africa
| | - Mike M Sathekge
- Department of Nuclear Medicine, University of Pretoria, Pretoria, 0001, South Africa
- Nuclear Medicine Research Infrastructure (NuMeRI), Steve Biko Academic Hospital, Pretoria, 0001, South Africa
| |
Collapse
|
2
|
Obeid K, Kanellopoulos P, Abouzayed A, Mattsson A, Tolmachev V, Nock BA, Maina T, Orlova A. GRPR-Antagonists Carrying DOTAGA-Chelator via Positively Charged Linkers: Perspectives for Prostate Cancer Theranostics. Pharmaceutics 2024; 16:513. [PMID: 38675174 PMCID: PMC11054746 DOI: 10.3390/pharmaceutics16040513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2024] [Revised: 04/01/2024] [Accepted: 04/04/2024] [Indexed: 04/28/2024] Open
Abstract
Gastrin-releasing peptide receptor (GRPR)-antagonists have served as motifs in the development of theranostic radioligands for prostate cancer. Our efforts have been focused on the development of radiolabeled RM26 (H-DPhe6-Gln7-Trp8-Ala9-Val10-Gly11-His12-Sta13-Leu14-NH2) analogs, such as [111In]In-DOTAGA-PEG2-RM26. We recently showed that its Gly11/Sar11-substituted version, [111In]In-AU-RM26-M1, resisted degradation by neprilysin (NEP) while in circulation and achieved higher tumor uptake in mice. We herein introduce the following three new AU-RM26-M1 mimics labeled with In-111, with basic residues in the linker: (i) AU-RM26-M2 (PEG2-Pip), (ii) AU-RM26-M3 (PEG2-Arg), and (iii) AU-RM26-M4 (Arg-Arg-Pip). These analogs were compared in PC-3 cells and animal models vs. AU-RM26-M1 (reference). The new analogs showed high affinity and specificity for the GRPR, exhibiting an uptake and distribution pattern in PC-3 cells typical for a radiolabeled GRPR-antagonist. They showed high stability in peripheral mice blood, except for [111In]In-AU-RM26-M3. AU-RM26-M4 achieved the highest tumor uptake and promising background clearance, followed by [111In]In-RM26-M2, showing lower background levels. These findings were confirmed for [111In]In-AU-RM26-M2 and [111In]In-AU-RM26-M4 by micro-SPECT/CT at 4 and 24 h post-injection. Hence, the type of positively charged residues in the linker of AU-RM26-M1 mimics strongly influenced biological behavior. The analogs with Pip next to DPhe6 demonstrated the best overall characteristics and warrant further investigation.
Collapse
Affiliation(s)
- Karim Obeid
- Department of Medicinal Chemistry, Uppsala University, 751 83 Uppsala, Sweden; (K.O.); (P.K.); (A.A.); (A.M.)
| | - Panagiotis Kanellopoulos
- Department of Medicinal Chemistry, Uppsala University, 751 83 Uppsala, Sweden; (K.O.); (P.K.); (A.A.); (A.M.)
- Molecular Radiopharmacy, INRaSTES, NCSR “Demokritos”, 15341 Athens, Greece; (B.A.N.); (T.M.)
| | - Ayman Abouzayed
- Department of Medicinal Chemistry, Uppsala University, 751 83 Uppsala, Sweden; (K.O.); (P.K.); (A.A.); (A.M.)
| | - Adam Mattsson
- Department of Medicinal Chemistry, Uppsala University, 751 83 Uppsala, Sweden; (K.O.); (P.K.); (A.A.); (A.M.)
| | - Vladimir Tolmachev
- Department of Immunology, Genetics and Pathology, Uppsala University, 751 83 Uppsala, Sweden;
| | - Berthold A. Nock
- Molecular Radiopharmacy, INRaSTES, NCSR “Demokritos”, 15341 Athens, Greece; (B.A.N.); (T.M.)
| | - Theodosia Maina
- Molecular Radiopharmacy, INRaSTES, NCSR “Demokritos”, 15341 Athens, Greece; (B.A.N.); (T.M.)
| | - Anna Orlova
- Department of Medicinal Chemistry, Uppsala University, 751 83 Uppsala, Sweden; (K.O.); (P.K.); (A.A.); (A.M.)
- Science for Life Laboratory, Uppsala University, 752 37 Uppsala, Sweden
| |
Collapse
|
3
|
Baun C, Naghavi-Behzad M, Hildebrandt MG, Gerke O, Thisgaard H. Gastrin-releasing peptide receptor as a theranostic target in breast cancer: a systematic scoping review. Semin Nucl Med 2024; 54:256-269. [PMID: 38342656 DOI: 10.1053/j.semnuclmed.2024.01.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 01/18/2024] [Accepted: 01/19/2024] [Indexed: 02/13/2024]
Abstract
The gastrin-releasing peptide receptor (GRPR) is known to be overexpressed in breast cancer, making it a promising target for both imaging and therapy within a theranostic framework. Various radioligands targeting GRPR have undergone investigation in preclinical and clinical studies related to breast cancer. This systematic scoping review aimed to assess the current evidence on GRPR-targeted radioligands for diagnostic and therapeutic applications in breast cancer. The methodology followed the PRISMA-ScR protocol. The literature search was conducted in September 2023 and encompassed MEDLINE, Embase, Cochrane, and Scopus databases. We included original peer-reviewed studies focused on breast cancer patients or in vivo breast cancer models. Two reviewers performed the study selection process independently. Data were extracted, synthesized, and categorized into preclinical and clinical studies, further subdivided based on radioligand properties. A total of 35 original studies were included in the review, with three of them evaluating therapeutic outcomes. The results indicated that GRPR-radioantagonists are superior to GRPR-agonists, exhibiting preferable in vivo stability, rapid, specific tumor targeting, and enhanced retention. Both preclinical and clinical evaluations demonstrated renal excretion and high uptake in normal GRPR-expressing tissue, primarily the pancreas. A significant positive correlation was observed between GRPR and estrogen-receptor expression. In the clinical setting, GRPR-radioligands effectively detected primary tumors and, to a lesser extent, lymph node metastases. Moreover, GRPR-targeted radioantagonists successfully identified distant metastases originating from various sites in advanced metastatic disease, strongly correlated with positive estrogen receptor expression. Preclinical therapeutic evaluation of GRPR-radioligands labeled with lutetium-177 showed promising tumor responses, and none of the studies reported any observed or measured side effects, indicating a safe profile. In conclusion, the evidence presented in this review indicates a preference for GRPR-targeted antagonists over agonists, owing to their superior kinetics and promising diagnostic potential. Clinical assessments suggested diagnostic value for GRPR-targeted theranostics in breast cancer patients, particularly those with high estrogen receptor expression. Nevertheless, in the therapeutic clinical context, paying attention to the radiation dose administered to the pancreas and kidneys is crucial.
Collapse
Affiliation(s)
- Christina Baun
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark; Department of Clinical Research, University of Southern Denmark, Odense, Denmark.
| | - Mohammad Naghavi-Behzad
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark; Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Malene Grubbe Hildebrandt
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark; Department of Clinical Research, University of Southern Denmark, Odense, Denmark; Center for Personalized Response Monitoring in Oncology (PREMIO), Odense University Hospital, Odense, Denmark; Centre for Innovative Medical Technology, Odense University Hospital, Odense, Denmark
| | - Oke Gerke
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark; Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Helge Thisgaard
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark; Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| |
Collapse
|
4
|
Kanellopoulos P, Mattsson A, Abouzayed A, Obeid K, Nock BA, Tolmachev V, Maina T, Orlova A. Preclinical evaluation of new GRPR-antagonists with improved metabolic stability for radiotheranostic use in oncology. EJNMMI Radiopharm Chem 2024; 9:13. [PMID: 38366299 PMCID: PMC10873254 DOI: 10.1186/s41181-024-00242-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 02/05/2024] [Indexed: 02/18/2024] Open
Abstract
BACKGROUND The gastrin-releasing peptide receptor (GRPR) has been extensively studied as a biomolecular target for peptide-based radiotheranostics. However, the lack of metabolic stability and the rapid clearance of peptide radioligands, including radiolabeled GRPR-antagonists, often impede clinical application. Aiming at circumventing these drawbacks, we have designed three new GRPR-antagonist radioligands using [99mTc]Tc-DB15 ([99mTc]Tc-N4-AMA-DIG-DPhe-Gln-Trp-Ala-Val-Sar-His-Leu-NHEt; AMA: p-aminomethylaniline; DIG: diglycolate) as a motif, due to its high GRPR-affinity and stability to neprilysin (NEP). The new analogues carry the DOTAGA-chelator (1,4,7,10-tetraazacyclododecane-1-glutaric acid-4,7,10-triacetic acid) through different linkers at the N-terminus to allow for labeling with the theranostic radionuclide pair In-111/Lu-177. After labeling with In-111 the following radioligands were evaluated: (i) [111In]In-AU-SAR-M1 ([111In]In-DOTAGA-AMA-DIG-DPhe-Gln-Trp-Ala-Val-Sar-His-Leu-NHEt), (ii) [111In]In-AU-SAR-M2 ([111In]In-[DOTAGA-Arg]AU-SAR-M1) and (iii) [111In]In-AU-SAR-M3 ([111In]In-[DOTAGA-DArg]AU-SAR-M1). RESULTS These radioligands were compared in a series of in vitro assays using prostate adenocarcinoma PC-3 cells and in murine models. They all displayed high and GRPR-specific uptake in PC-3 cells. Analysis of mice blood collected 5 min post-injection (pi) revealed similar or even higher metabolic stability of the new radioligands compared with [99mTc]Tc-DB15. The stability could be further increased when the mice were treated with Entresto® to in situ induce NEP-inhibition. In PC-3 xenograft-bearing mice, [111In]In-AU-SAR-M1 displayed the most favourable biodistribution profile, combining a good tumor retention with the highest tumor-to-organ ratios, with the kidneys as the dose-limiting organ. CONCLUSIONS These findings strongly point at AU-SAR-M1 as a promising radiotherapeutic candidate when labeled with Lu-177, or other medically appealing therapeutic radiometals, especially when combined with in situ NEP-inhibition. To this goal further investigations are currently pursued.
Collapse
Affiliation(s)
- Panagiotis Kanellopoulos
- Department of Medicinal Chemistry, Uppsala University, 75183, Uppsala, Sweden
- Molecular Radiopharmacy, INRaSTES, NCSR "Demokritos", 15341, Athens, Greece
| | - Adam Mattsson
- Department of Medicinal Chemistry, Uppsala University, 75183, Uppsala, Sweden
| | - Ayman Abouzayed
- Department of Medicinal Chemistry, Uppsala University, 75183, Uppsala, Sweden
| | - Karim Obeid
- Department of Medicinal Chemistry, Uppsala University, 75183, Uppsala, Sweden
| | - Berthold A Nock
- Molecular Radiopharmacy, INRaSTES, NCSR "Demokritos", 15341, Athens, Greece
| | - Vladimir Tolmachev
- Department of Immunology, Genetics and Pathology, Uppsala University, 75183, Uppsala, Sweden
| | - Theodosia Maina
- Molecular Radiopharmacy, INRaSTES, NCSR "Demokritos", 15341, Athens, Greece
| | - Anna Orlova
- Department of Medicinal Chemistry, Uppsala University, 75183, Uppsala, Sweden.
- Science for Life Laboratory, Uppsala University, 75237, Uppsala, Sweden.
| |
Collapse
|
5
|
Hoberück S, Zöphel K, Pomper MG, Rowe SP, Gafita A. One Hundred Years of the Tracer Principle. J Nucl Med 2023; 64:1998-2000. [PMID: 37884328 DOI: 10.2967/jnumed.123.266458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 09/27/2023] [Indexed: 10/28/2023] Open
Affiliation(s)
- Sebastian Hoberück
- Department of Nuclear Medicine, Faculty of Medicine, University Hospital Carl Gustav Carus, TU Dresden, Dresden, Germany
- Department of Nuclear Medicine, Helios Klinikum Erfurt, Erfurt, Germany
| | - Klaus Zöphel
- Department of Nuclear Medicine, Faculty of Medicine, University Hospital Carl Gustav Carus, TU Dresden, Dresden, Germany
- Department of Nuclear Medicine, Klinikum Chemnitz GmbH, Chemnitz, Germany; and
| | - Martin G Pomper
- Division of Nuclear Medicine and Molecular Imaging, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Steven P Rowe
- Division of Nuclear Medicine and Molecular Imaging, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Andrei Gafita
- Division of Nuclear Medicine and Molecular Imaging, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland
| |
Collapse
|
6
|
Damiana TST, Paraïso P, de Ridder C, Stuurman D, Seimbille Y, Dalm SU. Side-by-side comparison of the two widely studied GRPR radiotracers, radiolabeled NeoB and RM2, in a preclinical setting. Eur J Nucl Med Mol Imaging 2023; 50:3851-3861. [PMID: 37584725 PMCID: PMC10611828 DOI: 10.1007/s00259-023-06364-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 07/24/2023] [Indexed: 08/17/2023]
Abstract
INTRODUCTION NeoB and RM2 are the most investigated gastrin-releasing peptide receptor (GRPR)-targeting radiotracers in preclinical and clinical studies. Therefore, an extensive side-by-side comparison of the two radiotracers is valuable to demonstrate whether one has advantages over the other. Accordingly, this study aims to compare the in vitro and in vivo characteristics of radiolabeled NeoB and RM2 to guide future clinical studies. METHOD The stability of the radiolabeled GRPR analogs was determined in phosphate buffered saline (PBS), and commercially available mouse and human serum. Target affinity was determined by incubating human prostate cancer PC-3 cells with [177Lu]Lu-NeoB or [177Lu]Lu-RM2, + / - increasing concentrations of unlabeled NeoB, RM2, or Tyr4-bombesin (BBN). To determine uptake and specificity cells were incubated with [177Lu]Lu-NeoB or [177Lu]Lu-RM2 + / - Tyr4-BBN. Moreover, in vivo studies were performed to determine biodistribution and pharmacokinetics. Finally, radiotracer binding to various GRPR-expressing human cancer tissues was investigated. RESULTS Both radiotracers demonstrated high stability in PBS and human serum, but stability in mouse serum decreased substantially over time. Moreover, both radiotracers demonstrated high GRPR affinity and specificity, but a higher uptake of [177Lu]Lu-NeoB was observed in in vitro studies. In vivo, no difference in tumor uptake was seen. The most prominent difference in uptake in physiological organs was observed in the GRPR-expressing pancreas; [177Lu]Lu-RM2 had less pancreatic uptake and a shorter pancreatic half-life than [177Lu]Lu-NeoB. Furthermore, [177Lu]Lu-RM2 presented with a lower tumor-to-kidney ratio, while the tumor-to-blood ratio was lower for [177Lu]Lu-NeoB. The autoradiography studies revealed higher binding of radiolabeled NeoB to all human tumor tissues. CONCLUSION Based on these findings, we conclude that the in vivo tumor-targeting capability of radiolabeled NeoB and RM2 is similar. Additional studies are needed to determine whether the differences observed in physiological organ uptakes, i.e., the pancreas, kidneys, and blood, result in relevant differences in organ absorbed doses when the radiotracers are applied for therapeutic purposes.
Collapse
Affiliation(s)
- T S T Damiana
- Department of Radiology & Nuclear Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
| | - P Paraïso
- Department of Radiology & Nuclear Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
| | - C de Ridder
- Department of Experimental Urology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - D Stuurman
- Department of Radiology & Nuclear Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Y Seimbille
- Department of Radiology & Nuclear Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
| | - S U Dalm
- Department of Radiology & Nuclear Medicine, Erasmus Medical Center, Rotterdam, The Netherlands.
| |
Collapse
|
7
|
Yang YQ, Sun RF, Ge P, Li WX, Zhang X, Zhang J, Ye L, Zhang N, Wang SY, Lv MQ, Zhou DX. GRPR down-regulation inhibits spermatogenesis through Ca 2+ mediated by PLCβ/IP3R signaling pathway in long-term formaldehyde-exposed rats. Food Chem Toxicol 2023; 179:113998. [PMID: 37604300 DOI: 10.1016/j.fct.2023.113998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 08/02/2023] [Accepted: 08/17/2023] [Indexed: 08/23/2023]
Abstract
Formaldehyde (FA), which is known as an air pollutant, has been proven to induce male infertility. However, the underlying mechanism of FA-induced male infertility remains elusive. In this study, 24 male SD rats were exposed to different levels of FA (0, 0.5, 2.46, and 5 mg/m3) for eight consecutive weeks. Through HE staining and sperm smear, we observed that FA exposure resulted in spermatogenic injury and the sperm quality decreased in rats. The qRT-PCR and Western blot analysis further revealed that GRPR was down-regulated in testicular tissues of FA-exposed rats as well as primary spermatogenic cells. Meanwhile, ZDOCK uncovered an interaction between GRPR and PLCβ. In addition, the CCK8, Fluo 3-AM and Flow cytometry results showed that FA exposure suppressed the expression of GRPR, PLCβ and IP3R, consequently reducing the Ca2+ concentration in spermatogenic cells, inducing apoptosis and inhibiting proliferation of spermatogenic cells. Moreover, rescue experiments confirmed that promoting GRPR could improve intracellular Ca2+ concentration by upregulating PLCβ and IP3R, partially reducing the apoptosis and promoting the proliferation of FA-treated spermatogenic cells. These findings revealed that GRPR participates in spermatogenesis through Ca2+ mediated by the PLCβ/IP3R signaling pathway in FA-exposed rats.
Collapse
Affiliation(s)
- Yan-Qi Yang
- Department of Pathology, School of Basic Medical Sciences, Health Science Center, Xi'an Jiaotong University, Shaanxi, 710061, China; Institute of Genetics and Developmental Biology, Xi'an Jiaotong University, Shaanxi, 710061, China
| | - Rui-Fang Sun
- Department of Pathology, School of Basic Medical Sciences, Health Science Center, Xi'an Jiaotong University, Shaanxi, 710061, China; Institute of Genetics and Developmental Biology, Xi'an Jiaotong University, Shaanxi, 710061, China
| | - Pan Ge
- Department of Pathology, School of Basic Medical Sciences, Health Science Center, Xi'an Jiaotong University, Shaanxi, 710061, China; Institute of Genetics and Developmental Biology, Xi'an Jiaotong University, Shaanxi, 710061, China
| | - Wen-Xing Li
- Department of SURGICAL Oncology, Xi'an Jiaotong University Medical College First Affiliated Hospital, 277 West Yanta Road, Shaanxi, 710061, China
| | - Xiang Zhang
- Department of Electrocardiographic Diagnosis, Xi'an Children's Hospital, Xi'an, 710003, China
| | - Jian Zhang
- Department of Pathology, School of Basic Medical Sciences, Health Science Center, Xi'an Jiaotong University, Shaanxi, 710061, China; Institute of Genetics and Developmental Biology, Xi'an Jiaotong University, Shaanxi, 710061, China
| | - Lu Ye
- Medical School, Xi'an Jiaotong University, Shaanxi, 710061, China; Xi'an Fourth Hospital, Shaanxi, 710061, China
| | - Nan Zhang
- Department of Pathology, School of Basic Medical Sciences, Health Science Center, Xi'an Jiaotong University, Shaanxi, 710061, China; Institute of Genetics and Developmental Biology, Xi'an Jiaotong University, Shaanxi, 710061, China
| | - Si-Yu Wang
- Department of Pathology, School of Basic Medical Sciences, Health Science Center, Xi'an Jiaotong University, Shaanxi, 710061, China; Institute of Genetics and Developmental Biology, Xi'an Jiaotong University, Shaanxi, 710061, China
| | - Mo-Qi Lv
- Department of Pathology, School of Basic Medical Sciences, Health Science Center, Xi'an Jiaotong University, Shaanxi, 710061, China; Institute of Genetics and Developmental Biology, Xi'an Jiaotong University, Shaanxi, 710061, China.
| | - Dang-Xia Zhou
- Department of Pathology, School of Basic Medical Sciences, Health Science Center, Xi'an Jiaotong University, Shaanxi, 710061, China; Institute of Genetics and Developmental Biology, Xi'an Jiaotong University, Shaanxi, 710061, China.
| |
Collapse
|
8
|
Lepareur N, Ramée B, Mougin-Degraef M, Bourgeois M. Clinical Advances and Perspectives in Targeted Radionuclide Therapy. Pharmaceutics 2023; 15:1733. [PMID: 37376181 DOI: 10.3390/pharmaceutics15061733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 06/09/2023] [Accepted: 06/13/2023] [Indexed: 06/29/2023] Open
Abstract
Targeted radionuclide therapy has become increasingly prominent as a nuclear medicine subspecialty. For many decades, treatment with radionuclides has been mainly restricted to the use of iodine-131 in thyroid disorders. Currently, radiopharmaceuticals, consisting of a radionuclide coupled to a vector that binds to a desired biological target with high specificity, are being developed. The objective is to be as selective as possible at the tumor level, while limiting the dose received at the healthy tissue level. In recent years, a better understanding of molecular mechanisms of cancer, as well as the appearance of innovative targeting agents (antibodies, peptides, and small molecules) and the availability of new radioisotopes, have enabled considerable advances in the field of vectorized internal radiotherapy with a better therapeutic efficacy, radiation safety and personalized treatments. For instance, targeting the tumor microenvironment, instead of the cancer cells, now appears particularly attractive. Several radiopharmaceuticals for therapeutic targeting have shown clinical value in several types of tumors and have been or will soon be approved and authorized for clinical use. Following their clinical and commercial success, research in that domain is particularly growing, with the clinical pipeline appearing as a promising target. This review aims to provide an overview of current research on targeting radionuclide therapy.
Collapse
Affiliation(s)
- Nicolas Lepareur
- Comprehensive Cancer Center Eugène Marquis, 35000 Rennes, France
- Inserm, INRAE, Institut NUMECAN (Nutrition, Métabolismes et Cancer)-UMR 1317, Univ Rennes, 35000 Rennes, France
| | - Barthélémy Ramée
- Nuclear Medicine Department, Nantes University Hospital, 44000 Nantes, France
| | - Marie Mougin-Degraef
- Nuclear Medicine Department, Nantes University Hospital, 44000 Nantes, France
- Inserm, CNRS, CRCI2NA (Centre de Recherche en Cancérologie et Immunologie Intégrée Nantes-Angers)-UMR 1307, Université de Nantes, ERL 6001, 44000 Nantes, France
| | - Mickaël Bourgeois
- Nuclear Medicine Department, Nantes University Hospital, 44000 Nantes, France
- Inserm, CNRS, CRCI2NA (Centre de Recherche en Cancérologie et Immunologie Intégrée Nantes-Angers)-UMR 1307, Université de Nantes, ERL 6001, 44000 Nantes, France
- Groupement d'Intérêt Public ARRONAX, 1 Rue Aronnax, 44817 Saint Herblain, France
| |
Collapse
|
9
|
Gilardi L, Airò Farulla LS, Curigliano G, Corso G, Leonardi MC, Ceci F. FDG and Non-FDG Radiopharmaceuticals for PET Imaging in Invasive Lobular Breast Carcinoma. Biomedicines 2023; 11:biomedicines11051350. [PMID: 37239021 DOI: 10.3390/biomedicines11051350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 04/19/2023] [Accepted: 04/27/2023] [Indexed: 05/28/2023] Open
Abstract
Invasive lobular cancer (ILC) is the second most frequent histological type of breast cancer (BC) and includes a heterogeneous spectrum of diseases with unique characteristics, especially the infiltrative growth pattern and metastatic spread. [18F]fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (FDG-PET/CT) is extensively used in oncology and BC patient evaluation. Its role in ILCs is considered suboptimal due to its low FDG avidity. Therefore, ILCs could benefit from molecular imaging with non-FDG tracers that target other specific pathways, contributing to precision medicine. This narrative review aims to summarize the current literature on the use of FDG-PET/CT in ILC and to discuss future opportunities given by the development of innovative non-FDG radiotracers.
Collapse
Affiliation(s)
- Laura Gilardi
- Division of Nuclear Medicine, IEO European Institute of Oncology IRCCS, 20141 Milan, Italy
| | - Lighea Simona Airò Farulla
- Division of Nuclear Medicine, IEO European Institute of Oncology IRCCS, 20141 Milan, Italy
- Department of Oncology and Hemato-Oncology, University of Milan, 20122 Milan, Italy
| | - Giuseppe Curigliano
- Department of Oncology and Hemato-Oncology, University of Milan, 20122 Milan, Italy
- Division of New Drugs and Early Drug Development, IEO European Institute of Oncology IRCCS, 20141 Milan, Italy
| | - Giovanni Corso
- Department of Oncology and Hemato-Oncology, University of Milan, 20122 Milan, Italy
- Division of Breast Surgery, IEO European Institute of Oncology, IRCCS, 20141 Milan, Italy
- European Cancer Prevention Organization (ECP), 20122 Milan, Italy
| | | | - Francesco Ceci
- Division of Nuclear Medicine, IEO European Institute of Oncology IRCCS, 20141 Milan, Italy
- Department of Oncology and Hemato-Oncology, University of Milan, 20122 Milan, Italy
| |
Collapse
|
10
|
Nock BA, Kanellopoulos P, Joosten L, Mansi R, Maina T. Peptide Radioligands in Cancer Theranostics: Agonists and Antagonists. Pharmaceuticals (Basel) 2023; 16:ph16050674. [PMID: 37242457 DOI: 10.3390/ph16050674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 04/25/2023] [Accepted: 04/27/2023] [Indexed: 05/28/2023] Open
Abstract
The clinical success of radiolabeled somatostatin analogs in the diagnosis and therapy-"theranostics"-of tumors expressing the somatostatin subtype 2 receptor (SST2R) has paved the way for the development of a broader panel of peptide radioligands targeting different human tumors. This approach relies on the overexpression of other receptor-targets in different cancer types. In recent years, a shift in paradigm from internalizing agonists to antagonists has occurred. Thus, SST2R-antagonist radioligands were first shown to accumulate more efficiently in tumor lesions and clear faster from the background in animal models and patients. The switch to receptor antagonists was soon adopted in the field of radiolabeled bombesin (BBN). Unlike the stable cyclic octapeptides used in the case of somatostatin, BBN-like peptides are linear, fast to biodegradable and elicit adverse effects in the body. Thus, the advent of BBN-like antagonists provided an elegant way to obtain effective and safe radiotheranostics. Likewise, the pursuit of gastrin and exendin antagonist-based radioligands is advancing with exciting new outcomes on the horizon. In the present review, we discuss these developments with a focus on clinical results, commenting on challenges and opportunities for personalized treatment of cancer patients by means of state-of-the-art antagonist-based radiopharmaceuticals.
Collapse
Affiliation(s)
- Berthold A Nock
- Molecular Radiopharmacy, INRaSTES, NCSR "Demokritos", 15310 Athens, Greece
| | | | - Lieke Joosten
- Department of Medical Imaging, Nuclear Medicine, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Rosalba Mansi
- Division of Radiopharmaceutical Chemistry, Clinic of Radiology and Nuclear Medicine, University Hospital Basel, 4031 Basel, Switzerland
| | - Theodosia Maina
- Molecular Radiopharmacy, INRaSTES, NCSR "Demokritos", 15310 Athens, Greece
| |
Collapse
|
11
|
Verhoeven M, Handula M, van den Brink L, de Ridder CMA, Stuurman DC, Seimbille Y, Dalm SU. Pre- and Intraoperative Visualization of GRPR-Expressing Solid Tumors: Preclinical Profiling of Novel Dual-Modality Probes for Nuclear and Fluorescence Imaging. Cancers (Basel) 2023; 15:cancers15072161. [PMID: 37046825 PMCID: PMC10093582 DOI: 10.3390/cancers15072161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 02/21/2023] [Accepted: 04/04/2023] [Indexed: 04/08/2023] Open
Abstract
Image-guided surgery using a gastrin-releasing peptide receptor (GRPR)-targeting dual-modality probe could improve the accuracy of the resection of various solid tumors. The aim of this study was to further characterize our four previously developed GRPR-targeting dual-modality probes that vary in linker structures and were labeled with indium-111 and sulfo-cyanine 5. Cell uptake studies with GRPR-positive PC-3 cells and GRPR-negative NCI-H69 cells confirmed receptor specificity. Imaging and biodistribution studies at 4 and 24 h with 20 MBq/1 nmol [111In]In-12-15 were performed in nude mice bearing a PC-3 and NCI-H69 xenograft, and showed that the probe with only a pADA linker in the backbone had the highest tumor-to-organ ratios (T/O) at 24 h after injection (T/O > 5 for, e.g., prostate, muscle and blood). For this probe, a dose optimization study with three doses (0.75, 1.25 and 1.75 nmol; 20 MBq) revealed that the maximum image contrast was achieved with the lowest dose. Subsequently, the probe was successfully used for tumor excision in a simulated image-guided surgery setting. Moreover, it demonstrated binding to tissue sections of human prostate, breast and gastro-intestinal stromal tumors. In summary, our findings demonstrate that the developed dual-modality probe has the potential to aid in the complete surgical removal of GRPR-positive tumors.
Collapse
Affiliation(s)
- Marjolein Verhoeven
- Department of Radiology and Nuclear Medicine, Erasmus Medical Center, University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
| | - Maryana Handula
- Department of Radiology and Nuclear Medicine, Erasmus Medical Center, University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
| | - Lilian van den Brink
- Department of Radiology and Nuclear Medicine, Erasmus Medical Center, University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
| | - Corrina M. A. de Ridder
- Department of Experimental Urology, Erasmus Medical Center, University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
| | - Debra C. Stuurman
- Department of Radiology and Nuclear Medicine, Erasmus Medical Center, University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
| | - Yann Seimbille
- Department of Radiology and Nuclear Medicine, Erasmus Medical Center, University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
- Life Sciences Division, TRIUMF, Vancouver, BC V6T 2A3, Canada
| | - Simone U. Dalm
- Department of Radiology and Nuclear Medicine, Erasmus Medical Center, University Medical Center Rotterdam, 3015 GD Rotterdam, The Netherlands
| |
Collapse
|
12
|
Holik HA, Ibrahim FM, Elaine AA, Putra BD, Achmad A, Kartamihardja AHS. The Chemical Scaffold of Theranostic Radiopharmaceuticals: Radionuclide, Bifunctional Chelator, and Pharmacokinetics Modifying Linker. Molecules 2022; 27:molecules27103062. [PMID: 35630536 PMCID: PMC9143622 DOI: 10.3390/molecules27103062] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 04/27/2022] [Accepted: 05/05/2022] [Indexed: 11/16/2022] Open
Abstract
Therapeutic radiopharmaceuticals have been researched extensively in the last decade as a result of the growing research interest in personalized medicine to improve diagnostic accuracy and intensify intensive therapy while limiting side effects. Radiometal-based drugs are of substantial interest because of their greater versatility for clinical translation compared to non-metal radionuclides. This paper comprehensively discusses various components commonly used as chemical scaffolds to build radiopharmaceutical agents, i.e., radionuclides, pharmacokinetic-modifying linkers, and chelators, whose characteristics are explained and can be used as a guide for the researcher.
Collapse
Affiliation(s)
- Holis Abdul Holik
- Department of Pharmaceutical Analysis and Medicinal Chemistry, Faculty of Pharmacy, Universitas Padjadjaran, Sumedang 45363, Indonesia; (F.M.I.); (A.A.E.); (B.D.P.)
- Correspondence:
| | - Faisal Maulana Ibrahim
- Department of Pharmaceutical Analysis and Medicinal Chemistry, Faculty of Pharmacy, Universitas Padjadjaran, Sumedang 45363, Indonesia; (F.M.I.); (A.A.E.); (B.D.P.)
| | - Angela Alysia Elaine
- Department of Pharmaceutical Analysis and Medicinal Chemistry, Faculty of Pharmacy, Universitas Padjadjaran, Sumedang 45363, Indonesia; (F.M.I.); (A.A.E.); (B.D.P.)
| | - Bernap Dwi Putra
- Department of Pharmaceutical Analysis and Medicinal Chemistry, Faculty of Pharmacy, Universitas Padjadjaran, Sumedang 45363, Indonesia; (F.M.I.); (A.A.E.); (B.D.P.)
| | - Arifudin Achmad
- Department of Nuclear Medicine and Molecular Theranostics, Faculty of Medicine, Universitas Padjadjaran/Hasan Sadikin General Hospital, Bandung 40161, Indonesia; (A.A.); (A.H.S.K.)
- Oncology and Stem Cell Working Group, Faculty of Medicine, Universitas Padjadjaran, Bandung 40161, Indonesia
| | - Achmad Hussein Sundawa Kartamihardja
- Department of Nuclear Medicine and Molecular Theranostics, Faculty of Medicine, Universitas Padjadjaran/Hasan Sadikin General Hospital, Bandung 40161, Indonesia; (A.A.); (A.H.S.K.)
| |
Collapse
|
13
|
Nock BA, Kanellopoulos P, Chepurny OG, Rouchota M, Loudos G, Holz GG, Krenning EP, Maina T. Nonpeptidic Z360-Analogs Tagged with Trivalent Radiometals as Anti-CCK2R Cancer Theranostic Agents: A Preclinical Study. Pharmaceutics 2022; 14:pharmaceutics14030666. [PMID: 35336041 PMCID: PMC8954547 DOI: 10.3390/pharmaceutics14030666] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 03/11/2022] [Accepted: 03/15/2022] [Indexed: 02/05/2023] Open
Abstract
(1) Background: Theranostic approaches in the management of cholecystokinin subtype 2 receptor (CCK2R)-positive tumors include radiolabeled gastrin and CCK motifs. Moving toward antagonist-based CCK2R-radioligands instead, we herein present three analogs of the nonpeptidic CCK2R-antagonist Z360, GAS1/2/3. Each was conjugated to a different chelator (DOTA, NODAGA or DOTAGA) for labeling with medically relevant trivalent radiometals (e.g., Ga-68, In-111, Lu-177) for potential use as anti-CCK2R cancer agents; (2) Methods: The in vitro properties of the thee analogs were compared in stably transfected HEK293-CCK2R cells. Biodistribution profiles were compared in SCID mice bearing twin HEK293-CCK2R and wtHEK293 tumors; (3) Results: The GAS1/2/3 analogs displayed high CCK2R-affinity (lower nM-range). The radioligands were fairly stable in vivo and selectively targeted the HEK293-CCK2R, but not the CCK2R-negative wtHEK293 tumors in mice. Their overall pharmacokinetic profile was found strongly dependent on the radiometal-chelate. Results could be visualized by SPECT/CT for the [111In]In-analogs; (4) Conclusions: The present study highlighted the high impact of the radiometal-chelate on the end-pharmacokinetics of a new series of Z360-based radioligands, revealing candidates with promising properties for clinical translation. It also provided the impetus for the development of a new class of nonpeptidic radioligands for CCK2R-targeted theranostics of human cancer.
Collapse
Affiliation(s)
- Berthold A. Nock
- Molecular Radiopharmacy, INRASTES, NCSR “Demokritos”, 15341 Athens, Greece; (B.A.N.); (P.K.)
| | | | - Oleg G. Chepurny
- Departments of Medicine and Pharmacology, State University of New York (SUNY), Upstate Medical University, Syracuse, NY 13210, USA and Department of Chemistry, Syracuse University, Syracuse, NY 13244, USA; (O.G.C.); (G.G.H.)
| | - Maritina Rouchota
- BIOEMTECH, Lefkippos Attica Technology Park NCSR “Demokritos”, 15310 Athens, Greece; (M.R.); (G.L.)
| | - George Loudos
- BIOEMTECH, Lefkippos Attica Technology Park NCSR “Demokritos”, 15310 Athens, Greece; (M.R.); (G.L.)
| | - George G. Holz
- Departments of Medicine and Pharmacology, State University of New York (SUNY), Upstate Medical University, Syracuse, NY 13210, USA and Department of Chemistry, Syracuse University, Syracuse, NY 13244, USA; (O.G.C.); (G.G.H.)
| | - Eric P. Krenning
- Cyclotron Rotterdam BV, Erasmus MC, 3015 CE Rotterdam, The Netherlands;
| | - Theodosia Maina
- Molecular Radiopharmacy, INRASTES, NCSR “Demokritos”, 15341 Athens, Greece; (B.A.N.); (P.K.)
- Correspondence: ; Tel.: +30-210-650-3908 or +30-210-650-3891
| |
Collapse
|
14
|
Kankanamalage PH, Hoerres R, Ho KV, Anderson CJ, Gallazzi F, Hennkens HM. p-NCS-Bn-NODAGA as a bifunctional chelator for radiolabeling with the 186Re/99mTc-tricarbonyl core: Radiochemistry with model complexes and a GRPR-targeting peptide. Nucl Med Biol 2022; 108-109:1-9. [DOI: 10.1016/j.nucmedbio.2022.01.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 01/19/2022] [Accepted: 01/27/2022] [Indexed: 12/30/2022]
|
15
|
Maina T, Nock BA. Peptide radiopharmaceuticals for targeted diagnosis & therapy of human tumors. Nucl Med Mol Imaging 2022. [DOI: 10.1016/b978-0-12-822960-6.00078-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
|
16
|
Mansi R, Nock BA, Dalm SU, Busstra MB, van Weerden WM, Maina T. Radiolabeled Bombesin Analogs. Cancers (Basel) 2021; 13:cancers13225766. [PMID: 34830920 PMCID: PMC8616220 DOI: 10.3390/cancers13225766] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 11/13/2021] [Accepted: 11/15/2021] [Indexed: 12/16/2022] Open
Abstract
Simple Summary Recent medical advancements have strived for a personalized medicine approach to patients, aimed at optimizing therapy outcomes with minimum toxicity. In this respect, nuclear medicine methodologies have been playing increasingly important roles. For example, the overexpression of peptide receptors, such as the gastrin-releasing peptide receptor (GRPR), on tumor cells as opposed to their lack of expression in healthy surrounding tissues can be elegantly exploited with the aid of “smart” peptide carriers, such as the analogs of the amphibian 14-peptide bombesin (BBN). These molecules can bring clinically attractive radionuclides to malignant lesions in prostate, breast, and other human cancers, sparing healthy tissues. Depending upon the radionuclide in question, diagnostic imaging with single-photon emission computed tomography (SPECT) or positron emission tomography (PET) has been pursued, identifying patients who are eligible for peptide radionuclide receptor therapy (PRRT) in an integrated “theranostic” approach. In the present review, we (i) discuss the major steps taken in the development of anti-GRPR theranostic radioligands, with a focus on those selected for clinical testing; (ii) comment on the present status in this field of research; and (iii) reflect on the current limitations as well as on new opportunities for their broader and more successful clinical applications. Abstract The gastrin-releasing peptide receptor (GRPR) is expressed in high numbers in a variety of human tumors, including the frequently occurring prostate and breast cancers, and therefore provides the rationale for directing diagnostic or therapeutic radionuclides on cancer lesions after administration of anti-GRPR peptide analogs. This concept has been initially explored with analogs of the frog 14-peptide bombesin, suitably modified at the N-terminus with a number of radiometal chelates. Radiotracers that were selected for clinical testing revealed inherent problems associated with these GRPR agonists, related to low metabolic stability, unfavorable abdominal accumulation, and adverse effects. A shift toward GRPR antagonists soon followed, with safer analogs becoming available, whereby, metabolic stability and background clearance issues were gradually improved. Clinical testing of three main major antagonist types led to promising outcomes, but at the same time brought to light several limitations of this concept, partly related to the variation of GRPR expression levels across cancer types, stages, previous treatments, and other factors. Currently, these parameters are being rigorously addressed by cell biologists, chemists, nuclear medicine physicians, and other discipline practitioners in a common effort to make available more effective and safe state-of-the-art molecular tools to combat GRPR-positive tumors. In the present review, we present the background, current status, and future perspectives of this endeavor.
Collapse
Affiliation(s)
- Rosalba Mansi
- Division of Radiopharmaceutical Chemistry, Clinic of Radiology and Nuclear Medicine University Hospital Basel, 4031 Basel, Switzerland;
| | - Berthold A. Nock
- Molecular Radiopharmacy, INRaSTES, NCSR “Demokritos”, 15310 Athens, Greece;
| | - Simone U. Dalm
- Erasmus Medical Center Rotterdam, 3000 CA Rotterdam, The Netherlands; (S.U.D.); (M.B.B.); (W.M.v.W.)
| | - Martijn B. Busstra
- Erasmus Medical Center Rotterdam, 3000 CA Rotterdam, The Netherlands; (S.U.D.); (M.B.B.); (W.M.v.W.)
| | - Wytske M. van Weerden
- Erasmus Medical Center Rotterdam, 3000 CA Rotterdam, The Netherlands; (S.U.D.); (M.B.B.); (W.M.v.W.)
| | - Theodosia Maina
- Molecular Radiopharmacy, INRaSTES, NCSR “Demokritos”, 15310 Athens, Greece;
- Correspondence: ; Tel.: +30-650-3908/3891
| |
Collapse
|
17
|
[ 99mTc]Tc-DB15 in GRPR-Targeted Tumor Imaging with SPECT: From Preclinical Evaluation to the First Clinical Outcomes. Cancers (Basel) 2021; 13:cancers13205093. [PMID: 34680243 PMCID: PMC8533986 DOI: 10.3390/cancers13205093] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/07/2021] [Accepted: 10/08/2021] [Indexed: 12/15/2022] Open
Abstract
Diagnostic imaging and radionuclide therapy of prostate (PC) and breast cancer (BC) using radiolabeled gastrin-releasing peptide receptor (GRPR)-antagonists represents a promising approach. We herein propose the GRPR-antagonist based radiotracer [99mTc]Tc-DB15 ([99mTc]Tc-N4-AMA-DGA-DPhe6,Sar11,LeuNHEt13]BBN(6-13); N4: 6-carboxy-1,4,8,11-tetraazaundecane, AMA: aminomethyl-aniline, DGA: diglycolic acid) as a new diagnostic tool for GRPR-positive tumors applying SPECT/CT. The uptake of [99mTc]Tc-DB15 was tested in vitro in mammary (T-47D) and prostate cancer (PC-3) cells and in vivo in T-47D or PC-3 xenograft-bearing mice as well as in BC patients. DB15 showed high GRPR-affinity (IC50 = 0.37 ± 0.03 nM) and [99mTc]Tc-DB15 strongly bound to the cell-membrane of T-47D and PC-3 cells, according to a radiolabeled antagonist profile. In mice, the radiotracer showed high and prolonged GRPR-specific uptake in PC-3 (e.g., 25.56 ± 2.78 %IA/g vs. 0.72 ± 0.12 %IA/g in block; 4 h pi) and T-47D (e.g., 15.82 ± 3.20 %IA/g vs. 3.82 ± 0.30 %IA/g in block; 4 h pi) tumors, while rapidly clearing from background. In patients with advanced BC, the tracer could reveal several bone and soft tissue metastases on SPECT/CT. The attractive pharmacokinetic profile of [99mTc]DB15 in mice and its capability to target GRPR-positive BC lesions in patients highlight its prospects for a broader clinical use, an option currently being explored by ongoing clinical studies.
Collapse
|
18
|
Benard F, Bratanovic IJ. A Novel Radiotracer for Molecular Imaging and Therapy of Gastrin-Releasing Peptide Receptor Positive Prostate Cancer. J Nucl Med 2021; 63:424-430. [PMID: 34301778 DOI: 10.2967/jnumed.120.257758] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 06/06/2021] [Indexed: 11/16/2022] Open
Abstract
The gastrin-releasing peptide receptor (GRPR) is overexpressed in many solid malignancies, particularly in prostate and breast cancers, among others. We synthesized ProBOMB2, a novel bombesin derivative radiolabeled with 68Ga and 177Lu, and evaluated its ability to target GRPR in a preclinical model of human prostate cancer. Methods: ProBOMB2 was synthesized on solid phase using Fmoc chemistry. The chelator 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid was coupled to the N-terminus and separated from the GRPR-targeting sequence by a cationic 4-amino-(1-carboxymethyl)-piperidine spacer. Binding affinity for both human and murine GRPR was determined using a cell-based competition assay, while a calcium efflux assay was used to measure the agonist/antagonist properties of the derivatives. ProBOMB2 was radiolabeled with 177Lu and 68Ga. SPECT and PET imaging, and biodistribution studies were conducted using a preclinical prostate cancer model of male immunocompromised mice bearing GRPR-positive PC-3 human prostate cancer xenografts. Results: Ga-ProBOMB2 and Lu-ProBOMB2 bound to PC-3 cells with a Ki of 4.58±0.67 and 7.29±1.73 nM, respectively. 68Ga-ProBOMB2 and 177Lu-ProBOMB2 were radiolabeled with a radiochemical purity greater than 95%. Both radiotracers were primarily excreted via the renal pathway. PET images of PC-3 tumor xenografts were visualized with excellent contrast at 1 h and 2 h post-injection (p.i.) with 68Ga-ProBOMB2, and very low off-target organ accumulation. 177Lu-ProBOMB2 enabled clear visualization of PC-3 tumor xenografts by SPECT imaging at 1 h, 4 h, and 24 h p.i. 177Lu-ProBOMB2 displayed higher tumor uptake than 68Ga-ProBOMB2 at 1 h p.i. 177Lu-ProBOMB2 tumor uptake at 1 h, 4 h, and 24 h p.i. was 14.9±3.1, 4.8±2.1, and 1.7±0.3 %ID/g, respectively. Conclusion: 68Ga-ProBOMB2 and 177Lu-ProBOMB2 are promising radiotracers with limited pancreas uptake, good tumor uptake, and favorable pharmacokinetics for imaging and therapy of GRPR-expressing tumors.
Collapse
|
19
|
Solnes LB, Shokeen M, Pandit-Taskar N. Novel Agents and Future Perspectives on Theranostics. Semin Radiat Oncol 2021; 31:83-92. [PMID: 33246639 DOI: 10.1016/j.semradonc.2020.07.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
In the current era of precision medicine, there is renewed interest in radiopharmaceutical therapy and theranostics. The approval of somatostatin receceptor directed therapy and norepinephrine transporter targeted 131I-MIBG therapies by the FDA and the rapid progress of highly promising beta and alpha emitter tagged PSMA directed therapy of prostate cancer have stimulated clinically impactful changes in practice. Many novel strategies are being explored and novel radiopharmaceutical therapeutic agents including peptide based ligands as well as antibodies or antibody fragments are being developed preclinically or are in early phase clinical trials. While beta particle emitters have most commonly been used for targeted radiotherapy and radioimmunotargeting, there is an emerging interest in alpha emitters that cause greater density of ionization events leading to increased double-strand DNA damage and cluster breaks because of the high-energy particles within a shorter tissue range of penetration and thereby lower toxicity to adjacent normal tissues.
Collapse
Affiliation(s)
- Lilja B Solnes
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Monica Shokeen
- Department of Radiology, St. Louis, MO.; Department of Biomedical Engineering, St. Louis, MO.; Alvin J. Siteman Cancer Center Washington University School of Medicine, St. Louis, MO
| | - Neeta Pandit-Taskar
- Molecular Imaging and Therapy Service, Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, NY.; Department of Radiology, Weill Cornell Medical College, New York, NY..
| |
Collapse
|
20
|
Maina T, Thakur M. SPECT Radiochemistry. Mol Imaging 2021. [DOI: 10.1016/b978-0-12-816386-3.00023-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
|
21
|
Li X, Cai H, Wu X, Li L, Wu H, Tian R. New Frontiers in Molecular Imaging Using Peptide-Based Radiopharmaceuticals for Prostate Cancer. Front Chem 2020; 8:583309. [PMID: 33335885 PMCID: PMC7736158 DOI: 10.3389/fchem.2020.583309] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 10/27/2020] [Indexed: 02/05/2023] Open
Abstract
The high incidence of prostate cancer (PCa) increases the need for progress in its diagnosis, staging, and precise treatment. The overexpression of tumor-specific receptors for peptides in human cancer cells, such as gastrin-releasing peptide receptor, natriuretic peptide receptor, and somatostatin receptor, has indicated the ideal molecular basis for targeted imaging and therapy. Targeting these receptors using radiolabeled peptides and analogs have been an essential topic on the current forefront of PCa studies. Radiolabeled peptides have been used to target receptors for molecular imaging in human PCa with high affinity and specificity. The radiolabeled peptides enable optimal quick elimination from blood and normal tissues, producing high contrast for positron emission computed tomography and single-photon emission computed tomography imaging with high tumor-to-normal tissue uptake ratios. Owing to their successful application in visualization, peptide derivatives with therapeutic radionuclides for peptide receptor radionuclide therapy in PCa have been explored in recent years. These developments offer the promise of personalized, molecular medicine for individual patients. Hence, we review the preclinical and clinical literature in the past 20 years and focus on the newer developments of peptide-based radiopharmaceuticals for the imaging and therapy of PCa.
Collapse
Affiliation(s)
- Xin Li
- Department of Nuclear Medicine, West China Hospital, Sichuan University, Chengdu, China
| | - Huawei Cai
- Department of Nuclear Medicine, West China Hospital, Sichuan University, Chengdu, China
| | - Xiaoai Wu
- Department of Nuclear Medicine, West China Hospital, Sichuan University, Chengdu, China
| | - Li Li
- Department of Nuclear Medicine, West China Hospital, Sichuan University, Chengdu, China
| | - Haoxing Wu
- Department of Nuclear Medicine, Frontiers Science Center for Disease-Related Molecular Network, National Clinical Research Center for Geriatrics, West China Hospital and West China School of Medicine, Sichuan University, Chengdu, China
| | - Rong Tian
- Department of Nuclear Medicine, West China Hospital, Sichuan University, Chengdu, China
| |
Collapse
|
22
|
Barrabés S, Ng-Choi I, Martínez MÁ, Manzano BR, Jalón FA, Espino G, Feliu L, Planas M, de Llorens R, Massaguer A. A nucleus-directed bombesin derivative for targeted delivery of metallodrugs to cancer cells. J Inorg Biochem 2020; 212:111214. [PMID: 32919249 DOI: 10.1016/j.jinorgbio.2020.111214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 07/30/2020] [Accepted: 07/31/2020] [Indexed: 11/19/2022]
Abstract
We have synthesized a set of bombesin derivatives with the aim of exploring their tumor targeting properties to deliver metal-based chemotherapeutics into cancer cells. Peptide QRLGNQWAVGHLL-NH2 (BN3) was selected based on its high internalization in gastrin-releasing peptide receptor (GRPR)-overexpressing PC-3 cells. Three metallopeptides were prepared by incorporating the terpyridine Pt(II) complex [PtCl(cptpy)]Cl (1) (cptpy = 4'-(4-carboxyphenyl)-2,2':6,2″-terpyridine) at the N-terminus of BN3 or at the NƐ- or Nα-amino group of an additional Lys residue (1-BN3, Lys-1-BN3 and 1-Lys-BN3, respectively). 1-Lys-BN3 displayed the best cytotoxic activity (IC50: 19.2 ± 1.7 μM) and similar ability to intercalate into DNA than complex 1. Moreover, the polypyridine Ru(II) complex [Ru(bpy)2)(cmbpy)](PF6)2 (2) (bpy = 2,2'-bipyridine; cmbpy = 4-methyl-2,2'-bipyridine-4'-carboxylic acid), with proven activity as photosensitizer, was coupled to BN3 leading to metallopeptide 2-Lys-BN3. Upon photoactivation, 2-Lys-BN3 displayed 2.5-fold higher cytotoxicity against PC-3 cells (IC50: 7.6 ± 1.0 μM) than complex 2. To enhance the accumulation of the drugs into the cell nucleus, the nuclear localization signal (NLS) PKKKRKV was incorporated at the N-terminus of BN3. NLS-BN3 displayed higher cellular internalization along with nuclear biodistribution. Accordingly, metallopeptides 1-NLS-BN3 and 2-NLS-BN3 showed increased cytotoxicity (IC50: 12.0 ± 1.1 μM and 2.3 ± 1.1 μM). Interestingly, the phototoxic index of 2-NLS-BN3 was 8-fold higher than that of complex 2. Next, the selectivity towards cancer cells was explored using 1BR3.G fibroblasts. Higher selectivity indexes were obtained for 1-NLS-BN3 and 2-NLS-BN3 than for the unconjugated complexes. These results prove NLS-BN3 effective for targeted delivery of metallodrugs to GRPR-overexpressing cells and for enhancing the cytotoxic efficacy of metal-based photosensitizers.
Collapse
Affiliation(s)
- Sílvia Barrabés
- Departament de Biologia, Universitat de Girona, Maria Aurèlia Capmany 40, 17003 Girona, Spain
| | - Iteng Ng-Choi
- Departament de Química, Universitat de Girona, Maria Aurèlia Capmany 69, 17003 Girona, Spain
| | - María Ángeles Martínez
- Departament de Química, Universitat de Girona, Maria Aurèlia Capmany 69, 17003 Girona, Spain.
| | - Blanca R Manzano
- Universidad de Castilla-La Mancha, Facultad de Ciencias y Tecnologías Químicas-IRICA, Avda. Camilo J. Cela 10, 13071 Ciudad Real, Spain
| | - Félix A Jalón
- Universidad de Castilla-La Mancha, Facultad de Ciencias y Tecnologías Químicas-IRICA, Avda. Camilo J. Cela 10, 13071 Ciudad Real, Spain
| | - Gustavo Espino
- Departamento de Química, Universidad de Burgos, Pza. Misael Bañuelos s/n, 09001 Burgos, Spain
| | - Lidia Feliu
- Departament de Química, Universitat de Girona, Maria Aurèlia Capmany 69, 17003 Girona, Spain.
| | - Marta Planas
- Departament de Química, Universitat de Girona, Maria Aurèlia Capmany 69, 17003 Girona, Spain.
| | - Rafael de Llorens
- Departament de Biologia, Universitat de Girona, Maria Aurèlia Capmany 40, 17003 Girona, Spain
| | - Anna Massaguer
- Departament de Biologia, Universitat de Girona, Maria Aurèlia Capmany 40, 17003 Girona, Spain.
| |
Collapse
|
23
|
[ 99mTc]Tc-DB1 Mimics with Different-Length PEG Spacers: Preclinical Comparison in GRPR-Positive Models. Molecules 2020; 25:molecules25153418. [PMID: 32731473 PMCID: PMC7435657 DOI: 10.3390/molecules25153418] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Revised: 07/24/2020] [Accepted: 07/25/2020] [Indexed: 02/07/2023] Open
Abstract
Background: The frequent overexpression of gastrin-releasing peptide receptors (GRPRs) in human cancers provides the rationale for delivering clinically useful radionuclides to tumor sites using peptide carriers. Radiolabeled GRPR antagonists, besides being safer for human use, have often shown higher tumor uptake and faster background clearance than agonists. We herein compared the biological profiles of the GRPR-antagonist-based radiotracers [99mTc]Tc-[N4-PEGx-DPhe6,Leu-NHEt13]BBN(6-13) (N4: 6-(carboxy)-1,4,8,11-tetraazaundecane; PEG: polyethyleneglycol): (i) [99mTc]Tc-DB7 (x = 2), (ii) [99mTc]Tc-DB13 (x = 3), and (iii) [99mTc]Tc-DB14 (x = 4), in GRPR-positive cells and animal models. The impact of in situ neprilysin (NEP)-inhibition on in vivo stability and tumor uptake was also assessed by treatment of mice with phosphoramidon (PA). Methods: The GRPR affinity of DB7/DB13/DB14 was determined in PC-3 cell membranes, and cell binding of the respective [99mTc]Tc-radioligands was assessed in PC-3 cells. Each of [99mTc]Tc-DB7, [99mTc]Tc-DB13, and [99mTc]Tc-DB14 was injected into mice without or with PA coinjection and 5 min blood samples were analyzed by HPLC. Biodistribution was conducted at 4 h postinjection (pi) in severe combined immunodeficiency disease (SCID) mice bearing PC-3 xenografts without or with PA coinjection. Results: DB7, -13, and -14 displayed single-digit nanomolar affinities for GRPR. The uptake rates of [99mTc]Tc-DB7, [99mTc]Tc-DB13, and [99mTc]Tc-DB14 in PC-3 cells was comparable and consistent with a radioantagonist profile. The radiotracers were found to be ≈70% intact in mouse blood and >94% intact after coinjection of PA. Treatment of mice with PA enhanced tumor uptake. Conclusions: The present study showed that increase of PEG-spacer length in the [99mTc]Tc-DB7-[99mTc]Tc-DB13-[99mTc]Tc-DB14 series had little effect on GRPR affinity, specific uptake in PC-3 cells, in vivo stability, or tumor uptake. A significant change in in vivo stability and tumor uptake was observed only after treatment of mice with PA, without compromising the favorably low background radioactivity levels.
Collapse
|
24
|
Li R, Gao R, Wang Y, Liu Z, Xu H, Duan A, Zhang F, Ma L. Gastrin releasing peptide receptor targeted nano-graphene oxide for near-infrared fluorescence imaging of oral squamous cell carcinoma. Sci Rep 2020; 10:11434. [PMID: 32651409 PMCID: PMC7351765 DOI: 10.1038/s41598-020-68203-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 05/18/2020] [Indexed: 12/12/2022] Open
Abstract
Oral squamous cell carcinoma (OSCC) is the most common malignant tumor that occurs in the oral mucosa. Pathological biopsy is still the current gold standard for OSCC diagnosis; however, some drawbacks need to be overcome. Therefore, it is urgently needed to find a non-invasive targeted technology for OSCC early diagnosis. Fluorescent optical imaging using near infrared (NIR) dyes tagged to tumor specific target will benefit such developments. Gastrin releasing peptide receptor (GRPR) is an attractive target for OSCC imaging and therapy. In this study, we synthesized nano-graphene oxide (NGO) nanoparticles with GRPR-specific peptides AF750-6Ahx-Sta-BBN via hydrogen bond and π–π bonds (NGO-BBN-AF750), and investigated their receptor binding, cell uptake and internalization in HSC-3 cells. NGO-BBN-AF750 and AF750-6Ahx-Sta-BBN showed a similar binding affinity to GRPR on HSC-3 cells. In contrast to AF750-6Ahx-Sta-BBN antagonist peptide, NGO-BBN-AF750 showed cellular internalization property. Overall, this study proposes a NGO nanoclusters-based nanoprobe for GRPR targeted near-infrared fluorescence imaging for OSCC. Nanoparticle-based delivery systems have shown highly significant potential in the delivery of a wide range of therapeutic agents.
Collapse
Affiliation(s)
- Ran Li
- Shanxi Medical University School and Hospital of Stomatology, Taiyuan, 030001, China
| | - Ruifang Gao
- Shanxi Medical University School and Hospital of Stomatology, Taiyuan, 030001, China
| | - Yimei Wang
- Shanxi Medical University School and Hospital of Stomatology, Taiyuan, 030001, China
| | - Zhuanzhuan Liu
- Shanxi Medical University School and Hospital of Stomatology, Taiyuan, 030001, China
| | - Hang Xu
- Research Division/Biomolecular Imaging Center, Harry S. Truman Memorial Veterans' Hospital, Columbia, MO, 65201, USA.,Department of Radiology, University of Missouri, Columbia, MO, 65212, USA.,School of Pharmacy, Nanjing Medical University, Nanjing, 211100, Jiangsu, China
| | - Ailin Duan
- Shanxi Medical University School and Hospital of Stomatology, Taiyuan, 030001, China
| | - Fang Zhang
- Shanxi Medical University School and Hospital of Stomatology, Taiyuan, 030001, China.
| | - Lixin Ma
- Research Division/Biomolecular Imaging Center, Harry S. Truman Memorial Veterans' Hospital, Columbia, MO, 65201, USA. .,Department of Radiology, University of Missouri, Columbia, MO, 65212, USA.
| |
Collapse
|
25
|
Kaloudi A, Kanellopoulos P, Radolf T, Chepurny OG, Rouchota M, Loudos G, Andreae F, Holz GG, Nock BA, Maina T. [ 99mTc]Tc-DGA1, a Promising CCK 2R-Antagonist-Based Tracer for Tumor Diagnosis with Single-Photon Emission Computed Tomography. Mol Pharm 2020; 17:3116-3128. [PMID: 32568549 DOI: 10.1021/acs.molpharmaceut.0c00605] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Radiolabeled gastrin analogues have been proposed for theranostics of cholecystokinin subtype 2 receptor (CCK2R)-positive cancer. Peptide radioligands based on other receptor antagonists have displayed superior pharmacokinetics and higher biosafety than agonists. Here, we present DGA1, a derivative of the nonpeptidic CCK2R antagonist Z-360 carrying an acyclic tetraamine, for [99mTc]Tc labeling. Preclinical comparison of [99mTc]Tc-DGA1 with [99mTc]Tc-DG2 (CCK2R-agonist reference) was conducted in HEK293-CCK2R/CCK2i4svR cells and mice models, qualifying [99mTc]Tc-DGA1 for further study in patients with CCK2R-positive tumors and single-photon emission computed tomography/CT.
Collapse
Affiliation(s)
- Aikaterini Kaloudi
- Molecular Radiopharmacy, INRASTES, NCSR "Demokritos", 15310 Athens, Greece
| | | | - Thorsten Radolf
- piCHEM Forschungs-und Entwicklungs GmbH, Parkring 3, 8074 Grambach, Austria
| | - Oleg G Chepurny
- SUNY Upstate Medical University, IHP 4310 at 505 Irving Avenue, Syracuse, New York 13210, United States
| | - Maritina Rouchota
- BIOEMTECH, Lefkippos Attica Technology Park NCSR "Demokritos", 15310 Athens, Greece
| | - George Loudos
- BIOEMTECH, Lefkippos Attica Technology Park NCSR "Demokritos", 15310 Athens, Greece
| | - Fritz Andreae
- piCHEM Forschungs-und Entwicklungs GmbH, Parkring 3, 8074 Grambach, Austria
| | - George G Holz
- SUNY Upstate Medical University, IHP 4310 at 505 Irving Avenue, Syracuse, New York 13210, United States
| | | | - Theodosia Maina
- Molecular Radiopharmacy, INRASTES, NCSR "Demokritos", 15310 Athens, Greece
| |
Collapse
|
26
|
Cimini A, Ricci M, Chiaravalloti A, Filippi L, Schillaci O. Theragnostic Aspects and Radioimmunotherapy in Pediatric Tumors. Int J Mol Sci 2020; 21:ijms21113849. [PMID: 32481723 PMCID: PMC7312954 DOI: 10.3390/ijms21113849] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 05/22/2020] [Accepted: 05/27/2020] [Indexed: 12/19/2022] Open
Abstract
The use of theragnostic radiopharmaceuticals in nuclear medicine has grown rapidly over the years to combine the diagnosis and therapy of tumors. In this review, we performed web-based and desktop literature research to investigate and explain the potential role of theragnostic imaging in pediatric oncology. We focused primarily on patients with aggressive malignancies such as neuroblastoma and brain tumors, to select patients with the highest chance of benefit from personalized therapy. Moreover, the most critical and groundbreaking applications of radioimmunotherapy in children’s oncology were examined in this peculiar context. Preliminary results showed the potential feasibility of theragnostic imaging and radioimmunotherapy in pediatric oncology. They revealed advantages in the management of the disease, thereby allowing an intra-personal approach and adding new weapons to conventional therapies.
Collapse
Affiliation(s)
- Andrea Cimini
- Department of Biomedicine and Prevention, University Tor Vergata, 00133 Rome, Italy; (M.R.); (A.C.); (O.S.)
- Correspondence: ; Tel.: +39-062-090-2467
| | - Maria Ricci
- Department of Biomedicine and Prevention, University Tor Vergata, 00133 Rome, Italy; (M.R.); (A.C.); (O.S.)
| | - Agostino Chiaravalloti
- Department of Biomedicine and Prevention, University Tor Vergata, 00133 Rome, Italy; (M.R.); (A.C.); (O.S.)
- Nuclear Medicine Section, IRCCS Neuromed, 86077 Pozzilli, Italy
| | - Luca Filippi
- Nuclear Medicine Section, “Santa Maria Goretti” Hospital, 04100 Latina, Italy;
| | - Orazio Schillaci
- Department of Biomedicine and Prevention, University Tor Vergata, 00133 Rome, Italy; (M.R.); (A.C.); (O.S.)
- Nuclear Medicine Section, IRCCS Neuromed, 86077 Pozzilli, Italy
| |
Collapse
|
27
|
Lo WL, Liang CH, Chen LC, Lee SY, Lo SN, Chen MW, Lu RM, Liu IJ, Wu HC, Chang CH. Imaging and biodistribution of radiolabeled SP90 peptide in BT-483 tumor bearing mice. Appl Radiat Isot 2020; 161:109162. [PMID: 32561130 DOI: 10.1016/j.apradiso.2020.109162] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 03/22/2020] [Accepted: 03/27/2020] [Indexed: 01/01/2023]
Abstract
The objective of this study was to evaluate radiolabeled DOTA-SP90 as a radiotracer for breast cancer. The in vitro competition assay showed that radiolabeled DOTA-SP90 had significant binding affinity to BT-483 cancer cells. Biodistribution, nanoSPECT/CT and nanoPET/CT imaging results indicated that radiolabeled DOTA-SP90 can accumulate in tumors. In addition, radiolabeled DOTA-SP90 peptides can also detect metastatic tumors. Therefore, radiolabeled SP90 peptide may provide the potential capability as diagnostic agent for breast cancer patients.
Collapse
Affiliation(s)
- Wei-Lin Lo
- Isotope Application Division, Institute of Nuclear Energy Research, Taoyuan, Taiwan
| | - Chen-Hsien Liang
- Isotope Application Division, Institute of Nuclear Energy Research, Taoyuan, Taiwan
| | - Liang-Cheng Chen
- Isotope Application Division, Institute of Nuclear Energy Research, Taoyuan, Taiwan
| | - Shih-Ying Lee
- Isotope Application Division, Institute of Nuclear Energy Research, Taoyuan, Taiwan
| | - Sheng-Nan Lo
- Isotope Application Division, Institute of Nuclear Energy Research, Taoyuan, Taiwan
| | - Ming-Wei Chen
- Isotope Application Division, Institute of Nuclear Energy Research, Taoyuan, Taiwan
| | - Ruei-Min Lu
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - I-Ju Liu
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Han-Chung Wu
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan
| | - Chih-Hsien Chang
- Isotope Application Division, Institute of Nuclear Energy Research, Taoyuan, Taiwan.
| |
Collapse
|
28
|
Baranyai Z, Tircsó G, Rösch F. The Use of the Macrocyclic Chelator DOTA in Radiochemical Separations. Eur J Inorg Chem 2019. [DOI: 10.1002/ejic.201900706] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Zsolt Baranyai
- Bracco Research Centre Bracco Imaging spa Via Ribes 5 10010 Colleretto Giacosa (TO) Italy
| | - Gyula Tircsó
- Department of Physical Chemistry Faculty of Science and Technology University of Debrecen Egyetem tér 1 Debrecen 4032 Hungary
| | - Frank Rösch
- Institute of Nuclear Chemistry Johannes Gutenberg‐University of Mainz Fritz‐Strassmann‐Weg 2 55128 Mainz Germany
| |
Collapse
|
29
|
Gibbens-Bandala B, Morales-Avila E, Ferro-Flores G, Santos-Cuevas C, Meléndez-Alafort L, Trujillo-Nolasco M, Ocampo-García B. 177Lu-Bombesin-PLGA (paclitaxel): A targeted controlled-release nanomedicine for bimodal therapy of breast cancer. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2019; 105:110043. [PMID: 31546458 DOI: 10.1016/j.msec.2019.110043] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 06/26/2019] [Accepted: 07/31/2019] [Indexed: 12/28/2022]
Abstract
The gastrin-releasing peptide receptor (GRPr) is overexpressed in >75% of breast cancers. 177Lu-Bombesin (177Lu-BN) has demonstrated the ability to target GRPr and facilitate efficient delivery of therapeutic radiation doses to malignant cells. Poly(d,l‑lactide‑co‑glycolide) acid (PLGA) nanoparticles can work as smart drug controlled-release systems activated through pH changes. Considering that paclitaxel (PTX) is a first-line drug for cancer treatment, this work aimed to synthesize and chemically characterize a novel polymeric PTX-loaded nanosystem with grafted 177Lu-BN and to evaluate its performance as a targeted controlled-release nanomedicine for concomitant radiotherapy and chemotherapy of breast cancer. PLGA(PTX) nanoparticles were synthesized using the single emulsification-solvent evaporation method with PVA as a stabilizer in the presence of PTX. Thereafter, the activation of PLGA carboxylic groups for BN attachment through the Lys1-amine group was performed. Results of the chemical characterization by FT-IR, DLS, HPLC and SEM/TEM demonstrated the successful synthesis of BN-PLGA(PTX) with a hydrodynamic diameter of 163.54 ± 33.25 nm. The entrapment efficiency of paclitaxel was 92.8 ± 3.6%. The nanosystem showed an adequate controlled release of the anticancer drug, which increased significantly due to the pH change from neutral (pH = 7.4) to acidic conditions (pH = 5.3). After labeling with 177Lu and purification by ultrafiltration, 177Lu-BN-PLGA(PTX) was obtained with a radiochemical purity of 99 ± 1%. In vitro and in vivo studies using MDA-MB-231 breast cancer cells (GRPr-positive) demonstrated a 177Lu-BN-PLGA(PTX) specific uptake and a significantly higher cytotoxic effect for the radiolabeled nanosystem than the unlabeled BN-PLGA(PTX) nanoparticles. Using a pulmonary micrometastasis MDA-MB-231 model, the added value of 177Lu-BN-PLGA(PTX) for tumor imaging was confirmed. The 177Lu-BN-PLGA(PTX) nanomedicine is suitable as a targeted paclitaxel delivery system with concomitant radiotherapeutic effect for the treatment of GRPr-positive breast cancer.
Collapse
Affiliation(s)
- Brenda Gibbens-Bandala
- Departamento de Materiales Radiactivos, Instituto Nacional de Investigaciones Nucleares, Carretera México-Toluca S/N, Ocoyoacac, Estado de México 52750, Mexico; Facultad de Química, Universidad Autónoma del Estado de México, Paseo Tollocan S/N, Toluca, Estado de México 50180, Mexico
| | - Enrique Morales-Avila
- Facultad de Química, Universidad Autónoma del Estado de México, Paseo Tollocan S/N, Toluca, Estado de México 50180, Mexico
| | - Guillermina Ferro-Flores
- Departamento de Materiales Radiactivos, Instituto Nacional de Investigaciones Nucleares, Carretera México-Toluca S/N, Ocoyoacac, Estado de México 52750, Mexico
| | - Clara Santos-Cuevas
- Departamento de Materiales Radiactivos, Instituto Nacional de Investigaciones Nucleares, Carretera México-Toluca S/N, Ocoyoacac, Estado de México 52750, Mexico
| | | | - Maydelid Trujillo-Nolasco
- Departamento de Materiales Radiactivos, Instituto Nacional de Investigaciones Nucleares, Carretera México-Toluca S/N, Ocoyoacac, Estado de México 52750, Mexico; Facultad de Química, Universidad Autónoma del Estado de México, Paseo Tollocan S/N, Toluca, Estado de México 50180, Mexico
| | - Blanca Ocampo-García
- Departamento de Materiales Radiactivos, Instituto Nacional de Investigaciones Nucleares, Carretera México-Toluca S/N, Ocoyoacac, Estado de México 52750, Mexico.
| |
Collapse
|
30
|
Lymperis E, Kaloudi A, Kanellopoulos P, Krenning EP, de Jong M, Maina T, Nock BA. Comparative evaluation of the new GRPR-antagonist 111 In-SB9 and 111 In-AMBA in prostate cancer models: Implications of in vivo stability. J Labelled Comp Radiopharm 2019; 62:646-655. [PMID: 30963606 DOI: 10.1002/jlcr.3733] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Revised: 03/04/2019] [Accepted: 04/01/2019] [Indexed: 12/19/2022]
Abstract
Gastrin-releasing peptide receptors (GRPRs) are overexpressed in prostate cancer, representing attractive targets for diagnosis and therapy with bombesin (BBN)-like radioligands. GRPR-antagonists have lately attracted much attention owing to inherent biosafety and favorable pharmacokinetics. We herein present the GRPR-antagonist SB9 structurally resembling the known BBN-based agonist AMBA (SB9 = [Leu13 NHEt-desMet14 ]AMBA). The profiles of 111 In-SB9 and 111 In-AMBA were directly compared in PC-3 cells and tumor-bearing mice. SB9 and AMBA displayed high GRPR affinities. 111 In-AMBA strongly internalized in PC-3 cells, while 111 In-SB9 remained bound on the cell surface showing a typical GRPR-radioantagonist profile. 111 In-SB9 was more stable than 111 In-AMBA, but coinjection of the neprilysin (NEP) inhibitor phosphoramidon (PA) stabilized both in vivo. The radioligands displayed high tumor uptake (20.23 ± 3.41 %ID/g and 18.53 ± 1.54 %ID/g, respectively, at 4 hours pi), but 111 In-SB9 washed faster from background. PA coinjection led to significant increase of tumor uptake, combined with better clearance for 111 In-SB9. In short, this study has revealed superior pharmacokinetics and higher stability for the GRPR-antagonist 111 In-SB9 vs the corresponding agonist 111 In-AMBA consolidating previous evidence that GRPR antagonists are preferable to agonists for tumor imaging and therapy. It has also demonstrated that further pharmacokinetic improvements were feasible by in situ metabolic radioligand stabilization using PA.
Collapse
Affiliation(s)
| | | | | | - Eric P Krenning
- Cytrotron Rotterdam BV, Erasmus MC, Rotterdam, The Netherlands
| | - Marion de Jong
- Department of Radiology and Nuclear Medicine, Erasmus MC, Rotterdam, The Netherlands
| | - Theodosia Maina
- Molecular Radiopharmacy, INRASTES, NCSR "Demokritos", Athens, Greece
| | - Berthold A Nock
- Molecular Radiopharmacy, INRASTES, NCSR "Demokritos", Athens, Greece
| |
Collapse
|
31
|
Ramos-Alvarez I, Lee L, Mantey SA, Jensen RT. Development and Characterization of a Novel, High-Affinity, Specific, Radiolabeled Ligand for BRS-3 Receptors. J Pharmacol Exp Ther 2019; 369:454-465. [PMID: 30971479 DOI: 10.1124/jpet.118.255141] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 04/05/2019] [Indexed: 02/06/2023] Open
Abstract
Bombesin (Bn) receptor subtype 3(BRS-3) is an orphan G-protein-coupled receptor of the Bn family, which does not bind any natural Bn peptide with high affinity. Receptor knockout studies show that the animals develop diabetes, obesity, altered temperature control, and other central nervous system (CNS)/endocrine/gastrointestinal changes. It is present in CNS, peripheral tissues, and tumors; however, its role in normal physiology/pathophysiology, as well as its receptor localization/pharmacology is largely unknown, in part due to the lack of a convenient, specific, direct radiolabeled ligand. This study was designed to address this problem and to develop and characterize a specific radiolabeled ligand for BRS-3. The peptide antagonist Bantag-1 had >10,000-fold selectivity for human BRS-3 (hBRS-3) over other mammalian Bn receptors (BnRs) [i.e., gastrin-releasing peptide receptor (GRPR) and neuromedin B receptor (NMBR)]. Using iodogen and basic conditions, it was radiolabeled to high specific activity (2200 Ci/mmol) and found to bind with high affinity/specificity to hBRS-3. Binding was saturable, rapid, and reversible. The ligand only interacted with known BRS-3 ligands, and not with other specific GRPR/NMBR ligands or ligands for unrelated receptors. The magnitude of 125I-Bantag-1 binding correlated with BRS-3 mRNA expression and the magnitude of activation of phospholipase C in lung cancer cells, as well as readily identifying BRS-3 in lung cancer cells and normal tissues, allowing the direct assessment of BRS-3 receptor pharmacology/numbers on cells containing BRS-3 with other BnRs, which is usually the case. This circumvents the need for subtraction assays, which are now frequently used to assess BRS-3 indirectly using radiolabeled pan-ligands, which interact with all BnRs.
Collapse
Affiliation(s)
- Irene Ramos-Alvarez
- Digestive Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - Lingaku Lee
- Digestive Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - Samuel A Mantey
- Digestive Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - Robert T Jensen
- Digestive Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| |
Collapse
|
32
|
Kaloudi A, Lymperis E, Kanellopoulos P, Waser B, de Jong M, Krenning EP, Reubi JC, Nock BA, Maina T. Localization of 99mTc-GRP Analogs in GRPR-Expressing Tumors: Effects of Peptide Length and Neprilysin Inhibition on Biological Responses. Pharmaceuticals (Basel) 2019; 12:ph12010042. [PMID: 30897789 PMCID: PMC6469168 DOI: 10.3390/ph12010042] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 03/16/2019] [Accepted: 03/18/2019] [Indexed: 02/06/2023] Open
Abstract
The overexpression of gastrin-releasing peptide receptors (GRPRs) in frequently occurring human tumors has provided the opportunity to use bombesin (BBN) analogs as radionuclide carriers to cancer sites for diagnostic and therapeutic purposes. We have been alternatively exploring human GRP motifs of higher GRPR selectivity compared to frog BBN sequences aiming to improve pharmacokinetic profiles. In the present study, we compared two differently truncated human endogenous GRP motifs: GRP(14–27) and GRP(18–27). An acyclic tetraamine was coupled at the N-terminus to allow for stable binding of the SPECT radionuclide 99mTc. Their biological profiles were compared in PC-3 cells and in mice without or with coinjection of phosphoramidon (PA) to induce transient neprilysin (NEP) inhibition in vivo. The two 99mTc-N4-GRP(14/18–27) radioligands displayed similar biological behavior in mice. Coinjection of PA exerted a profound effect on in vivo stability and translated into notably improved radiolabel localization in PC-3 experimental tumors. Hence, this study has shown that promising 99mTc-radiotracers for SPECT imaging may indeed derive from human GRP sequences. Radiotracer bioavailability was found to be of major significance. It could be improved during in situ NEP inhibition resulting in drastically enhanced uptake in GRPR-expressing lesions.
Collapse
Affiliation(s)
- Aikaterini Kaloudi
- Molecular Radiopharmacy, INRASTES, NCSR "Demokritos", 15310 Athens, Greece.
| | - Emmanouil Lymperis
- Molecular Radiopharmacy, INRASTES, NCSR "Demokritos", 15310 Athens, Greece.
| | | | - Beatrice Waser
- Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, CH-3010 Berne, Switzerland.
| | - Marion de Jong
- Department of Radiology & Nuclear Medicine Erasmus MC, 3015 CN Rotterdam, The Netherlands.
| | - Eric P Krenning
- Cytrotron Rotterdam BV, Erasmus MC, 3015 CN Rotterdam, The Netherlands.
| | - Jean Claude Reubi
- Cell Biology and Experimental Cancer Research, Institute of Pathology, University of Berne, CH-3010 Berne, Switzerland.
| | - Berthold A Nock
- Molecular Radiopharmacy, INRASTES, NCSR "Demokritos", 15310 Athens, Greece.
| | - Theodosia Maina
- Molecular Radiopharmacy, INRASTES, NCSR "Demokritos", 15310 Athens, Greece.
| |
Collapse
|
33
|
Lymperis E, Kaloudi A, Kanellopoulos P, de Jong M, Krenning EP, Nock BA, Maina T. Comparing Gly 11/dAla 11-Replacement vs. the in-Situ Neprilysin-Inhibition Approach on the Tumor-targeting Efficacy of the 111In-SB3/ 111In-SB4 Radiotracer Pair. Molecules 2019; 24:molecules24061015. [PMID: 30871262 PMCID: PMC6471467 DOI: 10.3390/molecules24061015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 03/09/2019] [Accepted: 03/11/2019] [Indexed: 02/08/2023] Open
Abstract
Background: The GRPR-antagonist 68Ga-SB3 visualized prostate cancer lesions in animal models and in patients. Switching radiometal from 68Ga to 111In impaired tumor targeting in mice, but coinjection of the neprilysin (NEP)-inhibitor phosphoramidon (PA) stabilized 111In-SB3 in circulation and remarkably increased tumor uptake. We herein report on the biological profile of 111In-SB4: 111In-[dAla11]SB3. Methods: The biological responses of 111In-SB3/SB4 were compared in PC-3 cells and animal models. Results: Gly11/dAla11-replacement deteriorated GRPR-affinity (SB4 IC50: 10.7 ± 0.9 nM vs. SB3 IC50: 4.6 ± 0.3 nM) and uptake in PC-3 cells (111In-SB4: 1.3 ± 0.4% vs. 111In-SB3 16.2 ± 0.8% at 1 h). 111In-SB4 was more stable than 111In-SB3, but PA-coinjection stabilized both radiotracers in peripheral mice blood. Unmodified 111In-SB3 showed higher uptake in PC-3 xenografts (8.8 ± 3.0%ID/g) vs. 111In-SB4 (3.1 ± 1.1%ID/g) at 4 h pi. PA-coinjection improved tumor uptake, with 111In-SB3 still showing superior tumor targeting (38.3 ± 7.9%ID/g vs. 7.4 ± 0.3%ID/g for 111In-SB4). Conclusions: Replacement of Gly11 by dAla11 improved in vivo stability, however, at the cost of GRPR-affinity and cell uptake, eventually translating into inferior tumor uptake of 111In-SB4 vs. unmodified 111In-SB3. On the other hand, in-situ NEP-inhibition turned out to be a more efficient and direct strategy to optimize the in vivo profile of 111In-SB3, and potentially other peptide radiotracers.
Collapse
Affiliation(s)
- Emmanouil Lymperis
- Molecular Radiopharmacy, INRASTES, NCSR "Demokritos", 15310 Athens, Greece.
| | - Aikaterini Kaloudi
- Molecular Radiopharmacy, INRASTES, NCSR "Demokritos", 15310 Athens, Greece.
| | | | - Marion de Jong
- Department of Radiology, Erasmus MC, 3015 GD Rotterdam, The Netherlands.
| | - Eric P Krenning
- Cytrotron Rotterdam BV, Erasmus MC, 3015 GD Rotterdam, The Netherlands.
| | - Berthold A Nock
- Molecular Radiopharmacy, INRASTES, NCSR "Demokritos", 15310 Athens, Greece.
| | - Theodosia Maina
- Molecular Radiopharmacy, INRASTES, NCSR "Demokritos", 15310 Athens, Greece.
| |
Collapse
|
34
|
Zhuo L, Yang X, Liao W, Wang J, Wang H, Lv M, Wang G, Song H, Feng Y, Chen Y, Wei H, Yang Y, Zhao P. Comparative cell uptake study of FITC-/177Lu-labeled RM26 monomer, dimer and trimer on PC-3: improving binding affinity of gastrin releasing peptide receptor (GRPR) antagonist via bivalency/trivalency. J Radioanal Nucl Chem 2019. [DOI: 10.1007/s10967-018-6396-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
35
|
Baratto L, Jadvar H, Iagaru A. Prostate Cancer Theranostics Targeting Gastrin-Releasing Peptide Receptors. Mol Imaging Biol 2019; 20:501-509. [PMID: 29256046 DOI: 10.1007/s11307-017-1151-1] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Gastrin-releasing peptide receptors (GRPRs), part of the bombesin (BBN) family, are aberrantly overexpressed in many cancers, including those of the breast, prostate, pancreas, and lung, and therefore present an attractive target for cancer diagnosis and therapy. Different bombesin analogs have been radiolabeled and used for imaging diagnosis, staging, evaluation of biochemical recurrence, and assessment of metastatic disease in patients with prostate cancer. Recently, interest has shifted from BBN-like receptor agonists to antagonists, because the latter does not induce adverse effects and demonstrate superior in vivo pharmacokinetics. We review the preclinical and clinical literatures on the use of GRPRs as targets for imaging and therapy of prostate cancer, with a focus on the newer developments and theranostic potential of GRPR peptides.
Collapse
Affiliation(s)
- Lucia Baratto
- Department of Radiology, Stanford University, Stanford, CA, USA
| | - Hossein Jadvar
- Department of Radiology, University of Southern California, 2250 Alcazar Street, CSC 102, Los Angeles, CA, 90033, USA.
| | - Andrei Iagaru
- Department of Radiology, Stanford University, Stanford, CA, USA
| |
Collapse
|
36
|
Lau J, Rousseau E, Zhang Z, Uribe CF, Kuo HT, Zeisler J, Zhang C, Kwon D, Lin KS, Bénard F. Positron Emission Tomography Imaging of the Gastrin-Releasing Peptide Receptor with a Novel Bombesin Analogue. ACS OMEGA 2019; 4:1470-1478. [PMID: 30775647 PMCID: PMC6372246 DOI: 10.1021/acsomega.8b03293] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 01/03/2019] [Indexed: 06/09/2023]
Abstract
The gastrin-releasing peptide receptor (GRPR), a G protein-coupled receptor, is overexpressed in solid malignancies and particularly in prostate cancer. We synthesized a novel bombesin derivative, [68Ga]Ga-ProBOMB1, evaluated its pharmacokinetics and potential to image GRPR expression with positron emission tomography (PET), and compared it with [68Ga]Ga-NeoBOMB1. ProBOMB1 (DOTA-pABzA-DIG-d-Phe-Gln-Trp-Ala-Val-Gly-His-Leu-ψ(CH2N)-Pro-NH2) was synthesized by solid-phase peptide synthesis. The polyaminocarboxylate chelator 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) was coupled to the N-terminal and separated from the GRPR-targeting sequence by a p-aminomethylaniline-diglycolic acid (pABzA-DIG) linker. The binding affinity to GRPR was determined using a cell-based competition assay, whereas the agonist/antagonist property was determined with a calcium efflux assay. ProBOMB1 was radiolabeled with 68GaCl3. PET imaging and biodistribution studies were performed in male immunocompromised mice bearing PC-3 prostate cancer xenografts. Blocking experiments were performed with coinjection of [d-Phe6,Leu-NHEt13,des-Met14]bombesin(6-14). Dosimetry calculations were performed with OLINDA software. ProBOMB1 and the nonradioactive Ga-ProBOMB were obtained in 1.1 and 67% yield, respectively. The K i value of Ga-ProBOMB1 for GRPR was 3.97 ± 0.76 nM. Ga-ProBOMB1 behaved as an antagonist for GRPR. [68Ga]Ga-ProBOMB1 was obtained in 48.2 ± 10.9% decay-corrected radiochemical yield with 121 ± 46.9 GBq/μmol molar activity and >95% radiochemical purity. Imaging/biodistribution studies showed that the excretion of [68Ga]Ga-ProBOMB1 was primarily through the renal pathway. At 1 h postinjection (p.i.), PC-3 tumor xenografts were clearly delineated in PET images with excellent contrast. The tumor uptake for [68Ga]Ga-ProBOMB1 was 8.17 ± 2.57 percent injected dose per gram (% ID/g) and 9.83 ± 1.48% ID/g for [68Ga]Ga-NeoBOMB1, based on biodistribution studies at 1 h p.i. This corresponded to tumor-to-blood and tumor-to-muscle uptake ratios of 20.6 ± 6.79 and 106 ± 57.7 for [68Ga]Ga-ProBOMB1 and 8.38 ± 0.78 and 39.0 ± 12.6 for [68Ga]Ga-NeoBOMB1, respectively. Blockade with [d-Phe6,Leu-NHEt13,des-Met14]bombesin(6-14) significantly reduced the average uptake of [68Ga]Ga-ProBOMB1 in tumors by 62%. The total absorbed dose was lower for [68Ga]Ga-ProBOMB1 in all organs except for bladder compared with [68Ga]Ga-NeoBOMB1. Our data suggest that [68Ga]Ga-ProBOMB1 is an excellent radiotracer for imaging GRPR expression with PET. [68Ga]Ga-ProBOMB1 achieved a similar uptake as [68Ga]Ga-NeoBOMB1 in tumors, with enhanced contrast and lower whole-body absorbed dose.
Collapse
Affiliation(s)
- Joseph Lau
- Department
of Molecular Oncology, BC Cancer Research
Centre, 675 West 10th
Avenue, V5Z 1L3 Vancouver, British Columbia, Canada
| | - Etienne Rousseau
- Department
of Molecular Oncology, BC Cancer Research
Centre, 675 West 10th
Avenue, V5Z 1L3 Vancouver, British Columbia, Canada
- Département
de Médecine Nucléaire et Radiobiologie, Université de Sherbrooke, 3001 12e Avenue Nord, J1H 5N4 Sherbrooke, Quebec, Canada
| | - Zhengxing Zhang
- Department
of Molecular Oncology, BC Cancer Research
Centre, 675 West 10th
Avenue, V5Z 1L3 Vancouver, British Columbia, Canada
| | - Carlos F. Uribe
- Department
of Molecular Oncology, BC Cancer Research
Centre, 675 West 10th
Avenue, V5Z 1L3 Vancouver, British Columbia, Canada
| | - Hsiou-Ting Kuo
- Department
of Molecular Oncology, BC Cancer Research
Centre, 675 West 10th
Avenue, V5Z 1L3 Vancouver, British Columbia, Canada
| | - Jutta Zeisler
- Department
of Molecular Oncology, BC Cancer Research
Centre, 675 West 10th
Avenue, V5Z 1L3 Vancouver, British Columbia, Canada
| | - Chengcheng Zhang
- Department
of Molecular Oncology, BC Cancer Research
Centre, 675 West 10th
Avenue, V5Z 1L3 Vancouver, British Columbia, Canada
| | - Daniel Kwon
- Department
of Molecular Oncology, BC Cancer Research
Centre, 675 West 10th
Avenue, V5Z 1L3 Vancouver, British Columbia, Canada
| | - Kuo-Shyan Lin
- Department
of Molecular Oncology, BC Cancer Research
Centre, 675 West 10th
Avenue, V5Z 1L3 Vancouver, British Columbia, Canada
- Department
of Radiology, University of British Columbia, 2211 Wesbrook Mall, V6T 1Z7 Vancouver, British Columbia, Canada
| | - François Bénard
- Department
of Molecular Oncology, BC Cancer Research
Centre, 675 West 10th
Avenue, V5Z 1L3 Vancouver, British Columbia, Canada
- Department
of Radiology, University of British Columbia, 2211 Wesbrook Mall, V6T 1Z7 Vancouver, British Columbia, Canada
| |
Collapse
|
37
|
Lv M, Zhao P, Zhuo L, Liao W, Wang H, Yang X, Wang J, Wang G, Song H, Feng Y, Chen Y, Yang Y, Wei H. Binding and cytotoxicity of 131I-labeled gastrin-releasing peptide receptor antagonists modified by cell penetrating peptides. J Radioanal Nucl Chem 2019. [DOI: 10.1007/s10967-018-6307-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
38
|
Franco Machado J, Silva RD, Melo R, G Correia JD. Less Exploited GPCRs in Precision Medicine: Targets for Molecular Imaging and Theranostics. Molecules 2018; 24:E49. [PMID: 30583594 PMCID: PMC6337414 DOI: 10.3390/molecules24010049] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Revised: 12/07/2018] [Accepted: 12/09/2018] [Indexed: 12/18/2022] Open
Abstract
Precision medicine relies on individually tailored therapeutic intervention taking into account individual variability. It is strongly dependent on the availability of target-specific drugs and/or imaging agents that recognize molecular targets and patient-specific disease mechanisms. The most sensitive molecular imaging modalities, Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET), rely on the interaction between an imaging radioprobe and a target. Moreover, the use of target-specific molecular tools for both diagnostics and therapy, theranostic agents, represent an established methodology in nuclear medicine that is assuming an increasingly important role in precision medicine. The design of innovative imaging and/or theranostic agents is key for further accomplishments in the field. G-protein-coupled receptors (GPCRs), apart from being highly relevant drug targets, have also been largely exploited as molecular targets for non-invasive imaging and/or systemic radiotherapy of various diseases. Herein, we will discuss recent efforts towards the development of innovative imaging and/or theranostic agents targeting selected emergent GPCRs, namely the Frizzled receptor (FZD), Ghrelin receptor (GHSR-1a), G protein-coupled estrogen receptor (GPER), and Sphingosine-1-phosphate receptor (S1PR). The pharmacological and clinical relevance will be highlighted, giving particular attention to the studies on the synthesis and characterization of targeted molecular imaging agents, biological evaluation, and potential clinical applications in oncology and non-oncology diseases. Whenever relevant, supporting computational studies will be also discussed.
Collapse
Affiliation(s)
- João Franco Machado
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, CTN, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal.
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal.
| | - Rúben D Silva
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, CTN, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal.
| | - Rita Melo
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, CTN, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal.
- Center for Neuroscience and Cell Biology; Rua Larga, Faculdade de Medicina, Polo I, 1ºandar, Universidade de Coimbra, 3004-504 Coimbra, Portugal.
| | - João D G Correia
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, CTN, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal.
| |
Collapse
|
39
|
Gallium-68: methodology and novel radiotracers for positron emission tomography (2012–2017). Pharm Pat Anal 2018; 7:193-227. [DOI: 10.4155/ppa-2018-0016] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Commercial 68Ge/68Ga generators provide a means to produce positron emission tomography agents on site without use of a cyclotron. This development has led to a rapid growth of academic literature and patents ongallium-68 (68Ga). As 68Ga positron emission tomography agents usually involve a targeting moiety attached to a metal chelator, the development lends itself to the investigation of theragnostic applications; the 68Ga-based diagnostic is utilized to determine if the biological target is present and, if so, a therapeutic isotope (e.g., 177Lu, 225Ac) can be complexed with the same scaffold to generate a corresponding radiotherapeutic. This review considers patents issued between 2012 and 2017 that contain a 68Ga-labeled molecule indexed by Chemical Abstract Services (a division of the American Chemical Society).
Collapse
|
40
|
Renard-Penna R, Gauthé M, Talbot JN. Editorial Comment: Advances in MRI and PET of the prostate: concurrence or complementarity? Eur Radiol 2018; 28:3138-3140. [PMID: 29858639 DOI: 10.1007/s00330-018-5459-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 04/03/2018] [Indexed: 11/28/2022]
Abstract
This Editorial Comment refers to the articles "Diagnostic evaluation of magnetization transfer and diffusion kurtosis imaging for prostate cancer detection in a re-biopsy population" by Barrett T et al., Eur Radiol. 2017 Dec 8 and "18F-Fluciclovine PET/MRI for preoperative lymph node staging in high-risk prostate cancer patients" by Selnæs KM et al., Eur Radiol. 2018 Jan 2.
Collapse
Affiliation(s)
- Raphaële Renard-Penna
- Academic Departments of Radiology, Tenon and Pitié-Salpétrière Hospitals, AP-HP, Sorbonne Université, Paris, France. .,GRC5, ONCOTYPE-Uro, Institut Universitaire de Cancérologie, F-75020, Paris, France.
| | - Mathieu Gauthé
- Médecine Nucléaire, Hôpital Tenon AP-HP, Institut Universitaire de Cancérologie, Sorbonne Université, Paris, France
| | - Jean-Noël Talbot
- Médecine Nucléaire, Hôpital Tenon AP-HP, Institut Universitaire de Cancérologie, Sorbonne Université, Paris, France
| |
Collapse
|
41
|
Lymperis E, Kaloudi A, Sallegger W, Bakker IL, Krenning EP, de Jong M, Maina T, Nock BA. Radiometal-Dependent Biological Profile of the Radiolabeled Gastrin-Releasing Peptide Receptor Antagonist SB3 in Cancer Theranostics: Metabolic and Biodistribution Patterns Defined by Neprilysin. Bioconjug Chem 2018; 29:1774-1784. [PMID: 29664606 DOI: 10.1021/acs.bioconjchem.8b00225] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Recent advances in oncology involve the use of diagnostic/therapeutic radionuclide-carrier pairs that target cancer cells, offering exciting opportunities for personalized patient treatment. Theranostic gastrin-releasing peptide receptor (GRPR)-directed radiopeptides have been proposed for the management of GRPR-expressing prostate and breast cancers. We have recently introduced the PET tracer 68Ga-SB3 (SB3, DOTA- p-aminomethylaniline-diglycolic acid-DPhe-Gln-Trp-Ala-Val-Gly-His-Leu-NHEt), a receptor-radioantagonist that enables the visualization of GRPR-positive lesions in humans. Aiming to fully assess the theranostic potential of SB3, we herein report on the impact of switching 68Ga to 111In/177Lu-label on the biological properties of resulting radiopeptides. Notably, the bioavailability of 111In/177Lu-SB3 in mice drastically deteriorated compared with metabolically robust 68Ga-SB3, and as a result led to poorer 111In/177Lu-SB3 uptake in GRPR-positive PC-3 xenografts. The peptide cleavage sites were identified by chromatographic comparison of blood samples from mice intravenously receiving 111In/177Lu-SB3 with each of newly synthesized 111In/177Lu-SB3-fragments. Coinjection of the radioconjugates with the neprilysin (NEP)-inhibitor phosphoramidon led to full stabilization of 111In/177Lu-SB3 in peripheral mouse blood and resulted in markedly enhanced radiolabel uptake in the PC-3 tumors. In conclusion, in situ NEP-inhibition led to indistinguishable 68Ga/111In/177Lu-SB3 profiles in mice emphasizing the theranostic prospects of SB3 for clinical use.
Collapse
Affiliation(s)
- Emmanouil Lymperis
- Molecular Radiopharmacy, INRASTES , National Center for Scientific Research "Demokritos" , GR-15310 Athens , Greece
| | - Aikaterini Kaloudi
- Molecular Radiopharmacy, INRASTES , National Center for Scientific Research "Demokritos" , GR-15310 Athens , Greece
| | | | - Ingrid L Bakker
- Department of Radiology & Nuclear Medicine , Erasmus MC , 3015 CN Rotterdam , The Netherlands
| | - Eric P Krenning
- Cyclotron Rotterdam BV , Erasmus MC , 3015 CE Rotterdam , The Netherlands
| | - Marion de Jong
- Department of Radiology & Nuclear Medicine , Erasmus MC , 3015 CN Rotterdam , The Netherlands
| | - Theodosia Maina
- Molecular Radiopharmacy, INRASTES , National Center for Scientific Research "Demokritos" , GR-15310 Athens , Greece
| | - Berthold A Nock
- Molecular Radiopharmacy, INRASTES , National Center for Scientific Research "Demokritos" , GR-15310 Athens , Greece
| |
Collapse
|
42
|
Kurth J, Krause BJ, Schwarzenböck SM, Stegger L, Schäfers M, Rahbar K. External radiation exposure, excretion, and effective half-life in 177Lu-PSMA-targeted therapies. EJNMMI Res 2018; 8:32. [PMID: 29651569 PMCID: PMC5897276 DOI: 10.1186/s13550-018-0386-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 04/02/2018] [Indexed: 12/26/2022] Open
Abstract
Background Prostate-specific membrane antigen (PSMA)-targeted therapy with 177Lu-PSMA-617 is a therapeutic option for patients with metastatic castration-resistant prostate cancer (mCRPC). To optimize the therapy procedure, it is necessary to determine relevant parameters to define radiation protection and safety necessities. Therefore, this study aimed at estimating the ambient radiation exposure received by the patient. Moreover, the excreted activity was quantified. Results In total, 50 patients with mCRPC and treated with 177Lu-PSMA-617 (mean administered activity 6.3 ± 0.5 GBq) were retrospectively included in a bi-centric study. Whole-body dose rates were measured at a distance of 2 m at various time points after application of 177Lu-PSMA-617, and effective half-lives for different time points were calculated and compared. Radiation exposure to the public was approximated using the dose integral. For the estimation of the excreted activity, whole body measurements of 25 patients were performed at 7 time points. Unbound 177Lu-PSMA-617 was rapidly cleared from the body. After 4 h, approximately 50% and, after 12 h, approximately 70% of the administered activity were excreted, primarily via urine. The mean dose rates were the following: 3.6 ± 0.7 μSv/h at 2 h p. i., 1.6 ± 0.6 μSv/h at 24 h, 1.1 ± 0.5 μSv/h at 48 h, and 0.7 ± 0.4 μSv/h at 72 h. The mean effective half-life of the cohort was 40.5 ± 9.6 h (min 21.7 h; max 85.7 h). The maximum dose to individual members of the public per treatment cycle was ~ 250 ± 55 μSv when the patient was discharged from the clinic after 48 h and ~ 190 ± 36 μSv when the patient was discharged after 72 h. Conclusions In terms of the radiation exposure to the public, 177Lu-PSMA is a safe option of radionuclide therapy. As usually four (sometimes more) cycles of the therapy are performed, it must be conducted in a way that ensures that applicable legal requirements can be followed. In other words, the radiation exposure to the public and the concentration of activity in wastewater must be sub-marginal. Therefore, in certain countries, hospitalization of these patients is mandatory.
Collapse
Affiliation(s)
- J Kurth
- Department of Nuclear Medicine, Rostock University Medical Center, Gertrudenplatz 1, 18057, Rostock, Germany.
| | - B J Krause
- Department of Nuclear Medicine, Rostock University Medical Center, Gertrudenplatz 1, 18057, Rostock, Germany
| | - S M Schwarzenböck
- Department of Nuclear Medicine, Rostock University Medical Center, Gertrudenplatz 1, 18057, Rostock, Germany
| | - L Stegger
- Department of Nuclear Medicine, University Hospital Muenster, Muenster, Germany
| | - M Schäfers
- Department of Nuclear Medicine, University Hospital Muenster, Muenster, Germany
| | - K Rahbar
- Department of Nuclear Medicine, University Hospital Muenster, Muenster, Germany
| |
Collapse
|
43
|
Moreno P, Mantey SA, Lee SH, Ramos-Álvarez I, Moody TW, Jensen RT. A possible new target in lung-cancer cells: The orphan receptor, bombesin receptor subtype-3. Peptides 2018; 101:213-226. [PMID: 29410320 PMCID: PMC6159918 DOI: 10.1016/j.peptides.2018.01.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 01/27/2018] [Accepted: 01/31/2018] [Indexed: 12/11/2022]
Abstract
Human bombesin receptors, GRPR and NMBR, are two of the most frequently overexpressed G-protein-coupled-receptors by lung-cancers. Recently, GRPR/NMBR are receiving considerable attention because they act as growth factor receptors often in an autocrine manner in different lung-cancers, affect tumor angiogenesis, their inhibition increases the cytotoxic potency of tyrosine-kinase inhibitors reducing lung-cancer cellular resistance/survival and their overexpression can be used for sensitive tumor localization as well as to target cytotoxic agents to the cancer. The orphan BRS-3-receptor, because of homology is classified as a bombesin receptor but has received little attention, despite the fact that it is also reported in a number of studies in lung-cancer cells and has growth effects in these cells. To address its potential importance, in this study, we examined the frequency/relative quantitative expression of human BRS-3 compared to GRPR/NMBR and the effects of its activation on cell-signaling/growth in 13 different human lung-cancer cell-lines. Our results showed that BRS-3 receptor is expressed in 92% of the cell-lines and that it is functional in these cells, because its activation stimulates phospholipase-C with breakdown of phosphoinositides and changes in cytosolic calcium, stimulates ERK/MAPK and stimulates cell growth by EGFR transactivation in some, but not all, the lung-cancer cell-lines. These results suggest that human BRS-3, similar to GRPR/NMBR, is frequently ectopically-expressed by lung-cancer cells in which, it is functional, affecting cell signaling/growth. These results suggest that similar to GRPR/NMBR, BRS-3 should receive increased attention as possible approach for the development of novel treatments and/or diagnosis in lung-cancer.
Collapse
Affiliation(s)
- Paola Moreno
- Department of Health and Human Services, Digestive Diseases Branch, NIDDK, United States
| | - Samuel A Mantey
- Department of Health and Human Services, Digestive Diseases Branch, NIDDK, United States
| | - Suk H Lee
- Department of Health and Human Services, Digestive Diseases Branch, NIDDK, United States
| | - Irene Ramos-Álvarez
- Department of Health and Human Services, Digestive Diseases Branch, NIDDK, United States
| | - Terry W Moody
- Center for Cancer Research, Office of the Director, NCI, National Institutes of Health, Bethesda, MD 20892-1804, United States
| | - Robert T Jensen
- Department of Health and Human Services, Digestive Diseases Branch, NIDDK, United States.
| |
Collapse
|
44
|
NeoBOMB1, a GRPR-Antagonist for Breast Cancer Theragnostics: First Results of a Preclinical Study with [ 67Ga]NeoBOMB1 in T-47D Cells and Tumor-Bearing Mice. Molecules 2017; 22:molecules22111950. [PMID: 29137110 PMCID: PMC6150197 DOI: 10.3390/molecules22111950] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 11/06/2017] [Accepted: 11/08/2017] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND The GRPR-antagonist-based radioligands [67/68Ga/111In/177Lu]NeoBOMB1 have shown excellent theragnostic profiles in preclinical prostate cancer models, while [68Ga]NeoBOMB1 effectively visualized prostate cancer lesions in patients. We were further interested to explore the theragnostic potential of NeoBOMB1 in GRPR-positive mammary carcinoma, by first studying [67Ga]NeoBOMB1 in breast cancer models; Methods: We investigated the profile of [67Ga]NeoBOMB1, a [68Ga]NeoBOMB1 surrogate, in GRPR-expressing T-47D cells and animal models; Results: NeoBOMB1 (IC50s of 2.2 ± 0.2 nM) and [natGa]NeoBOMB1 (IC50s of 2.5 ± 0.2 nM) exhibited high affinity for the GRPR. At 37 °C [67Ga]NeoBOMB1 strongly bound to the T-47D cell-membrane (45.8 ± 0.4% at 2 h), internalizing poorly, as was expected for a radioantagonist. [67Ga]NeoBOMB1 was detected >90% intact in peripheral mouse blood at 30 min pi. In mice bearing T-47D xenografts, [67Ga]NeoBOMB1 specifically localized in the tumor (8.68 ± 2.9% ID/g vs. 0.6 ± 0.1% ID/g during GRPR-blockade at 4 h pi). The unfavorably high pancreatic uptake could be considerably reduced (206.29 ± 17.35% ID/g to 42.46 ± 1.31% ID/g at 4 h pi) by increasing the NeoBOMB1 dose from 10 pmol to 200 pmol, whereas tumor uptake remained unaffected. Notably, tumor values did not decline from 1 to 24 h pi; Conclusions: [67Ga]NeoBOMB1 can successfully target GRPR-positive breast cancer in animals with excellent prospects for clinical translation.
Collapse
|