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Delivery systems exploiting natural cell transport processes of macromolecules for intracellular targeting of Auger electron emitters. Nucl Med Biol 2019; 80-81:45-56. [PMID: 31810828 DOI: 10.1016/j.nucmedbio.2019.11.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 10/24/2019] [Accepted: 11/25/2019] [Indexed: 12/17/2022]
Abstract
The presence of Auger electrons (AE) among the decay products of a number of radionuclides makes these radionuclides an attractive means for treating cancer because these short-range electrons can cause significant damage in the immediate vicinity of the decomposition site. Moreover, the extreme locality of the effect provides a potential for selective eradication of cancer cells with minimal damage to adjacent normal cells provided that the delivery of the AE emitter to the most vulnerable parts of the cell can be achieved. Few cellular compartments have been regarded as the desired target site for AE emitters, with the cell nucleus generally recognized as the preferred site for AE decay due to the extreme sensitivity of nuclear DNA to direct damage by radiation of high linear energy transfer. Thus, the advantages of AE emitters for cancer therapy are most likely to be realized by their selective delivery into the nucleus of the malignant cells. To achieve this goal, delivery systems must combine a challenging complex of properties that not only provide cancer cell preferential recognition but also cell entry followed by transport into the cell nucleus. A promising strategy for achieving this is the recruitment of natural cell transport processes of macromolecules, involved in each of the aforementioned steps. To date, a number of constructs exploiting intracellular transport systems have been proposed for AE emitter delivery to the nucleus of a targeted cell. An example of such a multifunctional vehicle that provides smart step-by-step delivery is the so-called modular nanotransporter, which accomplishes selective recognition, binding, internalization, and endosomal escape followed by nuclear import of the delivered radionuclide. The current review will focus on delivery systems utilizing various intracellular transport pathways and their combinations in order to provide efficient targeting of AE to the cancer cell nucleus.
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Lee H, Riad A, Martorano P, Mansfield A, Samanta M, Batra V, Mach RH, Maris JM, Pryma DA, Makvandi M. PARP-1-Targeted Auger Emitters Display High-LET Cytotoxic Properties In Vitro but Show Limited Therapeutic Utility in Solid Tumor Models of Human Neuroblastoma. J Nucl Med 2019; 61:850-856. [PMID: 31676730 DOI: 10.2967/jnumed.119.233965] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 10/09/2019] [Indexed: 12/15/2022] Open
Abstract
The currently available therapeutic radiopharmaceutical for high-risk neuroblastoma, 131I-metaiodobenzylguanidine, is ineffective at targeting micrometastases because of the low-linear-energy-transfer (LET) properties of high-energy β-particles. In contrast, Auger radiation has high-LET properties with nanometer ranges in tissue, efficiently causing DNA damage when emitted near DNA. The aim of this study was to evaluate the cytotoxicity of targeted Auger therapy in preclinical models of high-risk neuroblastoma. Methods: We used a radiolabled poly(adenosine diphosphate ribose) polymerase (PARP) inhibitor called 125I-KX1 to deliver Auger radiation to PARP-1, a chromatin-binding enzyme overexpressed in neuroblastoma. The in vitro cytotoxicity of 125I-KX1 was assessed in 19 neuroblastoma cell lines, followed by in-depth pharmacologic analysis in a sensitive and resistant pair of cell lines. Immunofluorescence microscopy was used to characterize 125I-KX1-induced DNA damage. Finally, in vitro and in vivo microdosimetry was modeled from experimentally derived pharmacologic variables. Results: 125I-KX1 was highly cytotoxic in vitro across a panel of neuroblastoma cell lines, directly causing double-strand DNA breaks. On the basis of subcellular dosimetry, 125I-KX1 was approximately twice as effective as 131I-KX1, whereas cytoplasmic 125I-metaiodobenzylguanidine demonstrated low biological effectiveness. Despite the ability to deliver a focused radiation dose to the cell nuclei, 125I-KX1 remained less effective than its α-emitting analog 211At-MM4 and required significantly higher activity for equivalent in vivo efficacy based on tumor microdosimetry. Conclusion: Chromatin-targeted Auger therapy is lethal to high-risk neuroblastoma cells and has the potential to be used in micrometastatic disease. This study provides the first evidence for cellular lethality from a PARP-1-targeted Auger emitter, calling for further investigation into targeted Auger therapy.
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Affiliation(s)
- Hwan Lee
- Department of Radiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania; and
| | - Aladdin Riad
- Department of Radiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania; and
| | - Paul Martorano
- Department of Radiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania; and
| | - Adam Mansfield
- Department of Radiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania; and
| | - Minu Samanta
- Division of Oncology and Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Vandana Batra
- Division of Oncology and Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Robert H Mach
- Department of Radiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania; and
| | - John M Maris
- Division of Oncology and Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Daniel A Pryma
- Department of Radiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania; and
| | - Mehran Makvandi
- Department of Radiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania; and
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Ruigrok EAM, van Weerden WM, Nonnekens J, de Jong M. The Future of PSMA-Targeted Radionuclide Therapy: An Overview of Recent Preclinical Research. Pharmaceutics 2019; 11:E560. [PMID: 31671763 PMCID: PMC6921028 DOI: 10.3390/pharmaceutics11110560] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 10/23/2019] [Accepted: 10/24/2019] [Indexed: 12/15/2022] Open
Abstract
Prostate specific membrane antigen (PSMA) has become a major focus point in the research and development of prostate cancer (PCa) imaging and therapeutic strategies using radiolabeled tracers. PSMA has shown to be an excellent target for PCa theranostics because of its high expression on the membrane of PCa cells and the increase in expression during disease progression. Therefore, numerous PSMA-targeting tracers have been developed and (pre)clinically studied with promising results. However, many of these PSMA-targeting tracers show uptake in healthy organs such as the salivary glands, causing radiotoxicity. Furthermore, not all patients respond to PSMA-targeted radionuclide therapy (TRT). This created the necessity of additional preclinical research studies in which existing tracers are reevaluated and new tracers are developed in order to improve PSMA-TRT by protecting the (PSMA-expressing) healthy organs and improving tumor uptake. In this review we will give an overview of the recent preclinical research projects regarding PCa-TRT using PSMA-specific radiotracers, which will give an indication of where the PSMA-TRT research movement is going and what we can expect in future clinical trials.
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Affiliation(s)
- Eline A M Ruigrok
- Dept. of Radiology and Nuclear Medicine, Erasmus MC, 3015 GD Rotterdam, The Netherlands.
- Dept. of Experimental Urology, Erasmus MC, 3015 GD Rotterdam, The Netherlands.
| | | | - Julie Nonnekens
- Dept. of Radiology and Nuclear Medicine, Erasmus MC, 3015 GD Rotterdam, The Netherlands.
- Dept. of Molecular Genetics, Erasmus MC, 3015 GD Rotterdam, The Netherlands.
- Oncode Institute, Erasmus MC, 3015 GD Rotterdam, The Netherlands.
| | - Marion de Jong
- Dept. of Radiology and Nuclear Medicine, Erasmus MC, 3015 GD Rotterdam, The Netherlands.
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Banerjee SR, Kumar V, Lisok A, Chen J, Minn I, Brummet M, Boinapally S, Cole M, Ngen E, Wharram B, Brayton C, Hobbs RF, Pomper MG. 177Lu-labeled low-molecular-weight agents for PSMA-targeted radiopharmaceutical therapy. Eur J Nucl Med Mol Imaging 2019; 46:2545-2557. [PMID: 31399803 DOI: 10.1007/s00259-019-04434-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 07/09/2019] [Indexed: 11/29/2022]
Abstract
PURPOSE To develop a prostate-specific membrane antigen (PSMA)-targeted radiotherapeutic for metastatic castration-resistant prostate cancer (mCRPC) with optimized efficacy and minimized toxicity employing the β-particle radiation of 177Lu. METHODS We synthesized 14 new PSMA-targeted, 177Lu-labeled radioligands (177Lu-L1-177Lu-L14) using different chelating agents and linkers. We evaluated them in vitro using human prostate cancer PSMA(+) PC3 PIP and PSMA(-) PC3 flu cells and in corresponding flank tumor models. Efficacy and toxicity after 8 weeks were evaluated at a single administration of 111 MBq for 177Lu-L1, 177Lu-L3, 177Lu-L5 and 177Lu-PSMA-617. Efficacy of 177Lu-L1 was further investigated using different doses, and long-term toxicity was determined in healthy immunocompetent mice. RESULTS Radioligands were produced in high radiochemical yield and purity. Cell uptake and internalization indicated specific uptake only in PSMA(+) PC3 cells. 177Lu-L1, 177Lu-L3 and 177Lu-L5 demonstrated comparable uptake to 177Lu-PSMA-617 and 177Lu-PSMA-I&T in PSMA-expressing tumors up to 72 h post-injection. 177Lu-L1, 177Lu-L3 and 177Lu-L5 also demonstrated efficient tumor regression at 8 weeks. 177Lu-L1 enabled the highest survival rate. Necropsy studies of the treated group at 8 weeks revealed subacute damage to lacrimal glands and testes. No radiation nephropathy was observed 1 year post-treatment in healthy mice receiving 111 MBq of 177Lu-L1, most likely related to the fast renal clearance of this agent. CONCLUSIONS 177Lu-L1 is a viable clinical candidate for radionuclide therapy of PSMA-expressing malignancies because of its high tumor-targeting ability and low off-target radiotoxic effects.
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Affiliation(s)
- Sangeeta Ray Banerjee
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA. .,Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | - Vivek Kumar
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ala Lisok
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jian Chen
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Il Minn
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Mary Brummet
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Srikanth Boinapally
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Michael Cole
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ethel Ngen
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Bryan Wharram
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Cory Brayton
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Robert F Hobbs
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Martin G Pomper
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, MD, USA. .,Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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Winter G, Vogt A, Jiménez-Franco LD, Rinscheid A, Yousefzadeh-Nowshahr E, Solbach C, Beer AJ, Glatting G, Kletting P. Modelling the internalisation process of prostate cancer cells for PSMA-specific ligands. Nucl Med Biol 2019; 72-73:20-25. [PMID: 31260881 DOI: 10.1016/j.nucmedbio.2019.05.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 05/15/2019] [Accepted: 05/22/2019] [Indexed: 10/26/2022]
Abstract
INTRODUCTION In prostate-specific membrane antigen (PSMA)-targeting radioligand therapy, small molecules are regularly internalised by the tumour cells. To determine the effectiveness of these ligands, the internalised fraction over time is derived from cell studies. Parameters, such as the ligand concentration and the number of cells, are experiment-specific and therefore a comparison between ligands is difficult. A more objective approach that allows better comparison is desirable. Therefore, the aim of this work was to develop a compartmental model that fully describes all relevant pharmacokinetic interactions of PSMA-specific ligands with prostate cancer cells. METHODS Internalisation studies were performed using the lymph node carcinoma of the prostate cell line LNCaP C4-2 and the prostatic carcinoma cell line PC-3. A new protocol was established for the determination of the PSMA-binding specificity by surface plasmon resonance (SPR). The experimental data in combination with parameters from literature were used for the modelling approach. RESULTS A compartmental model which includes the relevant physiological mechanisms was developed. The basic model structure and some parameters originate from the literature. The PSMA-specific association and dissociation rates of Ga-PSMA-11 were measured using surface plasmon resonance technology. The ligand-induced internalisation and PSMA synthesis rates were estimated by fitting the developed model to experimental data obtained using LNCaP C4-2 cells. For all [68Ga]Ga-PSMA-11 concentrations and including four various incubation times, the ligand-induced internalisation was determined to be (3.6 ± 0.1) % min-1. CONCLUSIONS The presented approach is a prerequisite for better estimation and thus comparison of important ligand-cell interaction parameters, by combining SPR measurements, cell experiments and mathematical modelling. ADVANCES IN KNOWLEDGE AND IMPLICATIONS FOR PATIENT A compartmental model was developed for evaluation and comparison of PSMA-binding small molecules. A SPR protocol was established for the determination of PSMA-binding specificity.
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Affiliation(s)
- Gordon Winter
- Department of Nuclear Medicine, Ulm University, Ulm, Germany.
| | - Anja Vogt
- Department of Nuclear Medicine, Ulm University, Ulm, Germany
| | - Luis David Jiménez-Franco
- Department of Radiation Oncology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
| | - Andreas Rinscheid
- Department of Nuclear Medicine, Ulm University, Ulm, Germany; Medical Radiation Physics, Department of Nuclear Medicine, Ulm University, Ulm, Germany.
| | - Elham Yousefzadeh-Nowshahr
- Department of Nuclear Medicine, Ulm University, Ulm, Germany; Medical Radiation Physics, Department of Nuclear Medicine, Ulm University, Ulm, Germany.
| | | | - Ambros J Beer
- Department of Nuclear Medicine, Ulm University, Ulm, Germany.
| | - Gerhard Glatting
- Department of Nuclear Medicine, Ulm University, Ulm, Germany; Medical Radiation Physics, Department of Nuclear Medicine, Ulm University, Ulm, Germany.
| | - Peter Kletting
- Department of Nuclear Medicine, Ulm University, Ulm, Germany; Medical Radiation Physics, Department of Nuclear Medicine, Ulm University, Ulm, Germany.
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Theranostics for Advanced Prostate Cancer: Current Indications and Future Developments. Eur Urol Oncol 2019; 2:152-162. [PMID: 31017091 DOI: 10.1016/j.euo.2019.01.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 12/24/2018] [Accepted: 01/07/2019] [Indexed: 12/13/2022]
Abstract
CONTEXT Advanced prostate cancer (PCa) is a prominent cause of cancer death in men; positron emission tomography (PET) imaging may play a relevant role in detecting metastases and thus allowing a more tailored therapy in these patients. Radioligand therapy (RLT) may also gain relevance as a treatment strategy in advanced disease. OBJECTIVE The aim of this review is to highlight how the recently developed theranostic processes may become a part of both the available diagnostic and the therapy arsenal in advanced PCa patients. EVIDENCE ACQUISITION An expert panel of nuclear medicine physicians and a urologist, highly experienced in the fields of radionuclide imaging and RLT in advanced PCa, performed a nonsystematic review of the current indications, performance, limitations, and potential future developments of the currently available options in PCa theranostics. EVIDENCE SYNTHESIS Among PET radiotracers, prostate-specific membrane antigen (PSMA)-based compounds in advanced PCa are the focus of a continuously growing interest, mostly due to their potential relevance as theranostic agents. The impact of PSMA-based PET/computed tomography imaging on treatment strategies and prognosis is promising, but still not unquestionably clear. Potential applications may include a role as a gatekeeper to PSMA-directed RLT, as well as monitoring the spread of systemic disease. Currently, initial results seem to substantiate the role of PSMA-directed RLT in terms of feasibility and efficacy. CONCLUSIONS PSMA is a promising molecule for both imaging and therapy in advanced PCa patients; nevertheless, further studies are needed to investigate its role and to determine the impact of its side effects and its overall strategy outcome. PATIENT SUMMARY Prostate-specific membrane antigen (PSMA), a protein, is highly expressed on prostate cancer cells. The possibility to perform diagnostic imaging and subsequently administer therapies by the means of the same molecule is called "theranostics". In patients with advanced prostate cancer, PSMA might have a role in detecting disease spread through both positron emission tomography and single-photon emission computed tomography imaging, while treating prostate cancer systemic localizations with radioligand therapy. Further studies are needed to better determine patients' risks and benefits of these therapeutic approaches.
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Harmatys KM, Overchuk M, Chen J, Ding L, Chen Y, Pomper MG, Zheng G. Tuning Pharmacokinetics to Improve Tumor Accumulation of a Prostate-Specific Membrane Antigen-Targeted Phototheranostic Agent. Bioconjug Chem 2018; 29:3746-3756. [PMID: 30350576 DOI: 10.1021/acs.bioconjchem.8b00636] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We describe a simple and effective bioconjugation strategy to extend the plasma circulation of a low molecular weight targeted phototheranostic agent, which achieves high tumor accumulation (9.74 ± 2.26%ID/g) and high tumor-to-background ratio (10:1). Long-circulating pyropheophorbide (LC-Pyro) was synthesized with three functional building blocks: (1) a porphyrin photosensitizer for positron-emission tomography (PET)/fluorescence imaging and photodynamic therapy (PDT), (2) a urea-based prostate-specific membrane antigen (PSMA) targeting ligand, and (3) a peptide linker to prolong the plasma circulation time. With porphyrin's copper-64 chelating and optical properties, LC-Pyro demonstrated its dual-modality (fluorescence/PET) imaging potential for selective and quantitative tumor detection in subcutaneous, orthotopic, and metastatic murine models. The peptide linker in LC-Pyro prolonged its plasma circulation time about 8.5 times compared to its truncated analog. High tumor accumulation of LC-Pyro enabled potent PDT, which resulted in significantly delayed tumor growth in a subcutaneous xenograft model. This approach can be applied to improve the pharmacokinetics of existing and future targeted PDT agents for enhanced tumor accumulation and treatment efficacy.
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Affiliation(s)
- Kara M Harmatys
- Princess Margaret Cancer Centre , University Health Network , 101 College Street , Toronto , Ontario M5G 1L7 , Canada.,Department of Medical Biophysics , University of Toronto , 101 College Street , Toronto , Ontario M5G 1L7 , Canada
| | - Marta Overchuk
- Princess Margaret Cancer Centre , University Health Network , 101 College Street , Toronto , Ontario M5G 1L7 , Canada.,Institute of Biomaterials and Biomedical Engineering , University of Toronto , 164 College Street , Toronto , Ontario M5S 3G9 , Canada
| | - Juan Chen
- Princess Margaret Cancer Centre , University Health Network , 101 College Street , Toronto , Ontario M5G 1L7 , Canada
| | - Lili Ding
- Princess Margaret Cancer Centre , University Health Network , 101 College Street , Toronto , Ontario M5G 1L7 , Canada
| | - Ying Chen
- Johns Hopkins Medical School , 1550 Orleans Street, 492 CRB II , Baltimore , Maryland 21287 , United States
| | - Martin G Pomper
- Johns Hopkins Medical School , 1550 Orleans Street, 492 CRB II , Baltimore , Maryland 21287 , United States
| | - Gang Zheng
- Princess Margaret Cancer Centre , University Health Network , 101 College Street , Toronto , Ontario M5G 1L7 , Canada.,Institute of Biomaterials and Biomedical Engineering , University of Toronto , 164 College Street , Toronto , Ontario M5S 3G9 , Canada.,Department of Medical Biophysics , University of Toronto , 101 College Street , Toronto , Ontario M5G 1L7 , Canada
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Grudzinski J, Marsh I, Titz B, Jeffery J, Longino M, Kozak K, Lange K, Larrabee J, Weichmann A, Moser A, Bednarz B. CLR 125 Auger Electrons for the Targeted Radiotherapy of Triple-Negative Breast Cancer. Cancer Biother Radiopharm 2018; 33:87-95. [PMID: 29641256 DOI: 10.1089/cbr.2017.2376] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
PURPOSE Auger electrons emitted by radioisotopes such as 125I have a high linear energy transfer and short mean-free path in tissue (<10 μm), making them suitable for treating micrometastases while sparing normal tissues. The authors developed and subsequently investigated a cancer cell-selective small molecule phospholipid ether analog to deliver 125I to triple-negative breast cancer (TNBC) cells in vivo. METHODS A Current Good Manufacturing Practice (cGMP) method to radiolabel 125I-CLR1404 (CLR 125) with >95% radiochemical purity was established. To estimate CLR 125 in vivo dosimetry and identify dose-limiting organs, the biodistribution of the analog compound 124I-CLR1404 (CLR 124) was investigated using micro-positron emission tomography (PET)/computed tomography (CT) in conjunction with a Monte Carlo dosimetry platform to estimate CLR 125 dosimetry. In vivo antitumor efficacy was tested by injecting nude mice bearing either MDA-MB-231-luc orthotopic xenografts or lung metastases with 74 MBq (3.7 GBq/kg) of CLR 125 or an equivalent mass amount of nonradiolabeled CLR 125. Longitudinal tumor measurements using calipers and bioluminescence imaging were obtained for the xenografts and lung metastases, respectively. RESULTS Dosimetry analysis estimated that CLR 125 would impart the largest absorbed dose to the tumor per injected activity (0.261 ± 0.023 Gy/MBq) while the bone marrow, which is generally the dose-limiting organ for CLR1404, appears to have the lowest (0.063 ± 0.005 Gy/MBq). At administered activities of up to 74 MBq (3.7 GBq/kg), mice did not experience signs of toxicity. In addition, a single dose of CLR 125 reduced the volume of orthotopic primary TNBC xenografts by ∼60% compared to control vehicle (p < 0.001) and significantly extended survival. In addition, CLR 125 was efficacious against preclinical metastatic TNBC models by inhibiting the progression of micrometastases (p < 0.01). CONCLUSIONS Targeted radionuclide therapy with CLR 125 displayed significant antitumor efficacy in vivo, suggesting promise for treatment of TNBC micrometastases.
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Affiliation(s)
- Joseph Grudzinski
- 1 Department of Medical Physics, University of Wisconsin-Madison , Madison, Wisconsin
| | - Ian Marsh
- 1 Department of Medical Physics, University of Wisconsin-Madison , Madison, Wisconsin
| | | | - Justin Jeffery
- 3 University of Wisconsin Carbone Cancer Center , Madison, Wisconsin
| | - Marc Longino
- 2 Cellectar Biosciences, Inc. , Madison, Wisconsin
| | - Kevin Kozak
- 2 Cellectar Biosciences, Inc. , Madison, Wisconsin
| | | | | | - Ashley Weichmann
- 3 University of Wisconsin Carbone Cancer Center , Madison, Wisconsin
| | - Amy Moser
- 3 University of Wisconsin Carbone Cancer Center , Madison, Wisconsin.,4 Department of Human Oncology, University of Wisconsin-Madison , Madison, Wisconsin
| | - Bryan Bednarz
- 1 Department of Medical Physics, University of Wisconsin-Madison , Madison, Wisconsin.,3 University of Wisconsin Carbone Cancer Center , Madison, Wisconsin.,4 Department of Human Oncology, University of Wisconsin-Madison , Madison, Wisconsin
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Bavelaar BM, Lee BQ, Gill MR, Falzone N, Vallis KA. Subcellular Targeting of Theranostic Radionuclides. Front Pharmacol 2018; 9:996. [PMID: 30233374 PMCID: PMC6131480 DOI: 10.3389/fphar.2018.00996] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 08/13/2018] [Indexed: 12/16/2022] Open
Abstract
The last decade has seen rapid growth in the use of theranostic radionuclides for the treatment and imaging of a wide range of cancers. Radionuclide therapy and imaging rely on a radiolabeled vector to specifically target cancer cells. Radionuclides that emit β particles have thus far dominated the field of targeted radionuclide therapy (TRT), mainly because the longer range (μm-mm track length) of these particles offsets the heterogeneous expression of the molecular target. Shorter range (nm-μm track length) α- and Auger electron (AE)-emitting radionuclides on the other hand provide high ionization densities at the site of decay which could overcome much of the toxicity associated with β-emitters. Given that there is a growing body of evidence that other sensitive sites besides the DNA, such as the cell membrane and mitochondria, could be critical targets in TRT, improved techniques in detecting the subcellular distribution of these radionuclides are necessary, especially since many β-emitting radionuclides also emit AE. The successful development of TRT agents capable of homing to targets with subcellular precision demands the parallel development of quantitative assays for evaluation of spatial distribution of radionuclides in the nm-μm range. In this review, the status of research directed at subcellular targeting of radionuclide theranostics and the methods for imaging and quantification of radionuclide localization at the nanoscale are described.
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Affiliation(s)
| | | | | | | | - Katherine A. Vallis
- CR-UK/MRC Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, United Kingdom
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Wüstemann T, Haberkorn U, Babich J, Mier W. Targeting prostate cancer: Prostate-specific membrane antigen based diagnosis and therapy. Med Res Rev 2018; 39:40-69. [PMID: 29771460 DOI: 10.1002/med.21508] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 04/05/2018] [Accepted: 04/16/2018] [Indexed: 12/12/2022]
Abstract
The high incidence rates of prostate cancer (PCa) raise demand for improved therapeutic strategies. Prostate tumors specifically express the prostate-specific membrane antigen (PSMA), a membrane-bound protease. As PSMA is highly overexpressed on malignant prostate tumor cells and as its expression rate correlates with the aggressiveness of the disease, this tumor-associated biomarker provides the possibility to develop new strategies for diagnostics and therapy of PCa. Major advances have been made in PSMA targeting, ranging from immunotherapeutic approaches to therapeutic small molecules. This review elaborates the diversity of PSMA targeting agents while focusing on the radioactively labeled tracers for diagnosis and endoradiotherapy. A variety of radionuclides have been shown to either enable precise diagnosis or efficiently treat the tumor with minimal effects to nontargeted organs. Most small molecules with affinity for PSMA are based on either a phosphonate or a urea-based binding motif. Based on these pharmacophores, major effort has been made to identify modifications to achieve ideal pharmacokinetics while retaining the specific targeting of the PSMA binding pocket. Several tracers have now shown excellent clinical usability in particular for molecular imaging and therapy as proven by the efficiency of theranostic approaches in current studies. The archetypal expression profile of PSMA may be exploited for the treatment with alpha emitters to break radioresistance and thus to bring the power of systemic therapy to higher levels.
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Affiliation(s)
- Till Wüstemann
- Department for Nuclear Medicine, Heidelberg University Hospital, Heidelberg, Germany
| | - Uwe Haberkorn
- Department for Nuclear Medicine, Heidelberg University Hospital, Heidelberg, Germany.,German Cancer Consortium (DKTK), Heidelberg, Germany
| | - John Babich
- Department for Radiology, Weill Cornell Medicine, New York, NY, USA
| | - Walter Mier
- Department for Nuclear Medicine, Heidelberg University Hospital, Heidelberg, Germany
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Umbricht CA, Benešová M, Schibli R, Müller C. Preclinical Development of Novel PSMA-Targeting Radioligands: Modulation of Albumin-Binding Properties To Improve Prostate Cancer Therapy. Mol Pharm 2018; 15:2297-2306. [PMID: 29684274 DOI: 10.1021/acs.molpharmaceut.8b00152] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The treatment of metastatic castration-resistant prostate cancer (mCRPC) remains challenging with current treatment options. The development of more effective therapies is, therefore, urgently needed. Targeted radionuclide therapy with prostate-specific membrane antigen (PSMA)-targeting ligands has revealed promising clinical results. In an effort to optimize this concept, it was the aim of this study to design and investigate PSMA ligands comprising different types of albumin binders. PSMA-ALB-53 and PSMA-ALB-56 were designed by combining the glutamate-urea-based PSMA-binding entity, a DOTA chelator and an albumin binder based on the 4-( p-iodophenyl)-moiety or p-(tolyl)-moiety. The compounds were labeled with 177Lu (50 MBq/nmol) resulting in radioligands of high radiochemical purity (≥98%). Both radioligands were stable (≥98%) over 24 h in the presence of l-ascorbic acid. The uptake into PSMA-positive PC-3 PIP tumor cells in vitro was in the same range (54-58%) for both radioligands; however, 177Lu-PSMA-ALB-53 showed a 15-fold enhanced binding to human plasma proteins. Biodistribution studies performed in PC-3 PIP/flu tumor-bearing mice revealed high tumor uptake of 177Lu-PSMA-ALB-53 and 177Lu-PSMA-ALB-56, respectively, demonstrated by equal areas under the curves (AUCs) for both radioligands. The increased retention of 177Lu-PSMA-ALB-53 in the blood resulted in almost 5-fold lower tumor-to-blood AUC ratios when compared to 177Lu-PSMA-ALB-56. Kidney clearance of 177Lu-PSMA-ALB-56 was faster, and hence, the tumor-to-kidney AUC ratio was 3-fold higher than in the case of 177Lu-PSMA-ALB-53. Due to the more favorable tissue distribution profile, 177Lu-PSMA-ALB-56 was selected for a preclinical therapy study in PC-3 PIP tumor-bearing mice. The tumor growth delay after application of 177Lu-PSMA-ALB-56 and 177Lu-PSMA-617 applied at the same activities (2 or 5 MBq per mouse) revealed better antitumor effects in the case of 177Lu-PSMA-ALB-56. As a consequence, the survival of mice treated with 177Lu-PSMA-ALB-56 was prolonged when compared to the mice, which received the same activity of 177Lu-PSMA-617. Our results demonstrated the superiority of 177Lu-PSMA-ALB-56 over 177Lu-PSMA-ALB-53 indicating that the p-(tolyl)-moiety was more suited as an albumin binder to optimize the tissue distribution profile. 177Lu-PSMA-ALB-56 was more effective to treat tumors than 177Lu-PSMA-617 resulting in complete tumor remission in four out of six mice. This promising results warrant further investigations to assess the potential for clinical application of 177Lu-PSMA-ALB-56.
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Affiliation(s)
- Christoph A Umbricht
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ , Paul Scherrer Institut , 5232 Villigen-PSI , Switzerland
| | - Martina Benešová
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ , Paul Scherrer Institut , 5232 Villigen-PSI , Switzerland.,Department of Chemistry and Applied Biosciences , ETH Zurich , 8093 Zurich , Switzerland
| | - Roger Schibli
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ , Paul Scherrer Institut , 5232 Villigen-PSI , Switzerland.,Department of Chemistry and Applied Biosciences , ETH Zurich , 8093 Zurich , Switzerland
| | - Cristina Müller
- Center for Radiopharmaceutical Sciences ETH-PSI-USZ , Paul Scherrer Institut , 5232 Villigen-PSI , Switzerland.,Department of Chemistry and Applied Biosciences , ETH Zurich , 8093 Zurich , Switzerland
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Trifunctional PSMA-targeting constructs for prostate cancer with unprecedented localization to LNCaP tumors. Eur J Nucl Med Mol Imaging 2018; 45:1841-1851. [PMID: 29623376 DOI: 10.1007/s00259-018-4004-5] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 03/26/2018] [Indexed: 12/11/2022]
Abstract
PURPOSE Treatment of late-stage prostate cancer by targeted radiotherapeutics such as 131I-MIP-1095 and 177Lu-PSMA-617 has shown encouraging early results. Lu-177 is preferred to I-131 in clinical settings, but targeted radioligand therapy (RLT) with 177Lu-PSMA-617 has not reached its full potential due to insufficient dose delivery to the tumor. We recently developed a dual-targeting radioiodinated ligand, RPS-027, that targets PSMA and uses albumin binding to enable good tumor uptake and significantly reduced kidney uptake in a preclinical model. Further development of this ligand is limited by the inability to independently modify PSMA and albumin binding and the requirement of I-131 for therapeutic application. We therefore sought to devise a new class of trifunctional ligands for RLT with (1) a high-affinity PSMA-binding domain, (2) an albumin-binding group (ABG), and (3) a chelator for radiometals such as 68Ga3+, 177Lu3+ and 225Ac3+. METHODS Ligands incorporating a triazolylphenylurea-containing PSMA-targeting group, an Nε-(2-(4-iodophenyl)acetyl)lysine ABG and the bifunctional chelator p-SCN-Bn-DOTA linked by a PEG-containing polymer containing 0,3,4,6,8 or 12 repeats were prepared. PSMA affinity was determined in LNCaP cells and uptake and tissue distribution was studied in mice bearing LNCaP tumor xenografts and compared to 177Lu-PSMA-617. Imaging studies were performed up to 24 h post-injection (p.i.) using 66Ga3+ and biodistribution studies at 4 h, 24 h and 96 h p.i. with 177Lu3+. RESULTS PSMA affinity was high (IC50 = 1-10 nM) and inversely proportional to the linker length. Tumor uptake correlated with binding affinity and was significantly greater than for 177Lu-PSMA-617 over 96 h. The highest uptake was achieved with 177Lu-RPS-063 (30.0 ± 6.9 %ID/g; 4 h p.i.). Kidney uptake was generally high, with the exception of the lowest affinity ligand 177Lu-RPS-067. Each of the compounds showed slower blood clearance than 177Lu-PSMA-617, with clearance proportional to linker length. CONCLUSIONS The high tumor uptake achieved with these trifunctional ligands predicts larger (up to 4×) doses delivered to the tumor than can be achieved with 177Lu-PSMA-617. Although PSMA-mediated kidney uptake was also observed, the exceptional area under the curve (AUC) in the tumor warrants further investigation of these novel ligands as candidates for RLT.
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Virgolini I, Decristoforo C, Haug A, Fanti S, Uprimny C. Current status of theranostics in prostate cancer. Eur J Nucl Med Mol Imaging 2018; 45:471-495. [PMID: 29282518 PMCID: PMC5787224 DOI: 10.1007/s00259-017-3882-2] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 11/07/2017] [Indexed: 12/25/2022]
Abstract
The aim of this review is to report on the current status of prostate-specific membrane antigen (PSMA)-directed theranostics in prostate cancer (PC) patients. The value of 68Ga-PSMA-directed PET imaging as a diagnostic procedure for primary and recurrent PC as well as the role of evolving PSMA radioligand therapy (PRLT) in castration-resistant (CR)PC is assessed. The most eminent data from mostly retrospective studies currently available on theranostics of prostate cancer are discussed. The current knowledge on 68Ga-PSMA PET/CT implicates that primary staging with PET/CT is meaningful in patients with high-risk PC and that the combination with pelvic multi parametric (mp)MR (or PET/mpMR) reaches the highest impact on patient management. There may be a place for 68Ga-PSMA PET/CT in intermediate-risk PC patients as well, however, only a few data are available at the moment. In secondary staging for local recurrence, 68Ga-PSMA PET/mpMR is superior to PET/CT, whereas for distant recurrence, PET/CT has equivalent results and is faster and cheaper compared to PET/mpMR. 68Ga-PSMA PET/CT is superior to 18F / 11Choline PET/CT in primary staging as well as in secondary staging. In patients with biochemical relapse, PET/CT positivity is directly associated with prostate-specific antigen (PSA) increase and amounts to roughly 50% when PSA is raised to ≤0.5 ng/ml and to ≥90% above 1 ng/ml. Significant clinical results have so far been achieved with the subsequent use of radiolabeled PSMA ligands in the treatment of CRPC. Accumulated activities of 30 to 50 GBq of 177Lu-PSMA ligands seem to be clinically safe with biochemical response and PERCIST/RECIST response in around 75% of patients along with xerostomia in 5-10% of patients as the only notable side effect. On the basis of the current literature, we conclude that PSMA-directed theranostics do have a major clinical impact in diagnosis and therapy of PC patients. We recommend that 68Ga-PSMA PET/CT should be performed in primary staging together with pelvic mpMR in high-risk patients and in all patients for secondary staging, and that PSMA-directed therapy is a potent strategy in CRPC patients when other treatment options have failed. The combination of PSMA-directed therapy with existing therapy modalities (such as 223Ra-chloride or androgen deprivation therapy) has to be explored, and prospective clinical multicenter trials with theranostics are warranted.
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Affiliation(s)
- Irene Virgolini
- Department of Nuclear Medicine, Medical University of Innsbruck, Anichstraße 35, 6020, Innsbruck, Austria.
| | - Clemens Decristoforo
- Department of Nuclear Medicine, Medical University of Innsbruck, Anichstraße 35, 6020, Innsbruck, Austria
| | - Alexander Haug
- Department of Radiology and Nuclear Medicine, Medical University of Vienna, 18-20 Währinger Gürtel, 1090, Vienna, Austria
| | - Stefano Fanti
- Nuclear Medicine Unit, University of Bologna, S. Orsola Hospital Bologna, Massarenti 9, 40138, Bologna, Italy
| | - Christian Uprimny
- Department of Nuclear Medicine, Medical University of Innsbruck, Anichstraße 35, 6020, Innsbruck, Austria
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64
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Fluorescent light-up acridine orange derivatives bind and stabilize KRAS-22RT G-quadruplex. Biochimie 2018; 144:144-152. [DOI: 10.1016/j.biochi.2017.11.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Accepted: 11/06/2017] [Indexed: 01/17/2023]
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65
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Nimmagadda S, Pullambhatla M, Chen Y, Parsana P, Lisok A, Chatterjee S, Mease R, Rowe SP, Lupold S, Pienta KJ, Pomper MG. Low-Level Endogenous PSMA Expression in Nonprostatic Tumor Xenografts Is Sufficient for In Vivo Tumor Targeting and Imaging. J Nucl Med 2017; 59:486-493. [PMID: 29025989 DOI: 10.2967/jnumed.117.191221] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 09/27/2017] [Indexed: 01/25/2023] Open
Abstract
Prostate-specific membrane antigen (PSMA) is highly expressed in prostate cancer and within the neovasculature of other solid tumors. The nonprostatic expression of PSMA has been reported exclusively within the neovasculature endothelial cells of nonprostatic cancers; however, there are few reports on PSMA expression in epithelial cells. Herein, we describe PSMA expression in nonprostatic epithelial cells and characterize the potential of PSMA-binding agents to noninvasively detect that expression. Methods: PSMA expression data were extracted from publicly available genomic databases. Genomic data were experimentally validated for PSMA expression-by quantitative reverse transcription polymerase chain reaction, flow cytometry, and Western blotting-in several nonprostatic cell lines and xenografts of melanoma and small cell lung cancer (SCLC) origin. The feasibility of PSMA detection in those tumor models was further established using PSMA-based nuclear and optical imaging agents and by biodistribution, blocking, and ex vivo molecular characterization studies. Results: We discovered that a small percentage of nonprostatic cancer cell lines and tumors express PSMA. Importantly, PSMA expression was sufficiently high to image established melanoma and SCLC xenografts using PSMA-based nuclear and optical imaging agents. Conclusion: These results indicate that PSMA expression in nonprostatic tumors may not be limited to the endothelium but may also include solid tumor tissue of nonprostatic cancers including melanoma and SCLC. Our observations indicate broader applicability of PSMA-targeted imaging and therapeutics.
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Affiliation(s)
- Sridhar Nimmagadda
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, Maryland .,Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Mrudula Pullambhatla
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Ying Chen
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Princy Parsana
- Department of Computer Science, Johns Hopkins Medical Institutions, Baltimore, Maryland; and
| | - Ala Lisok
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Samit Chatterjee
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Ronnie Mease
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, Maryland.,Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Steven P Rowe
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Shawn Lupold
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins Medical Institutions, Baltimore, Maryland.,James Buchanan Brady Urological Institute and Department of Urology, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Kenneth J Pienta
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins Medical Institutions, Baltimore, Maryland.,James Buchanan Brady Urological Institute and Department of Urology, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Martin G Pomper
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, Maryland.,Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins Medical Institutions, Baltimore, Maryland.,James Buchanan Brady Urological Institute and Department of Urology, Johns Hopkins Medical Institutions, Baltimore, Maryland
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66
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Kelly JM, Amor-Coarasa A, Nikolopoulou A, Kim D, Williams C, Vallabhajosula S, Babich JW. Assessment of PSMA targeting ligands bearing novel chelates with application to theranostics: Stability and complexation kinetics of 68Ga 3+, 111In 3+, 177Lu 3+ and 225Ac 3. Nucl Med Biol 2017; 55:38-46. [PMID: 29055836 DOI: 10.1016/j.nucmedbio.2017.10.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2017] [Revised: 09/21/2017] [Accepted: 10/01/2017] [Indexed: 01/12/2023]
Abstract
INTRODUCTION Recent successes in the treatment of metastatic castration-resistant prostate cancer (mCRPCa) by systemic endoradiotherapy has sparked renewed interest in developing small molecule ligands targeting prostate-specific membrane antigen (PSMA) and chelators capable of stable complexation of metal radionuclides for imaging and therapy. As the size and coordination number of metals for imaging, such as 68Ga3+, and for targeted therapy, such as 177Lu3+ and 225Ac3+, are substantially different, they may show a preference for macrocycles of different denticity. We have prepared three simple conjugates that target PSMA and form radiometal complexes through coordination by either octa-, deca-, or dodecadentate tetraazacyclododecane chelators. The complex formation and metal ion selectivity of these constructs were determined at two relevant temperatures, complex stability was examined in vitro, and tumor targeting was demonstrated in preclinical PCa models with a view towards identifying a candidate with potential value as a theranostic agent for the imaging and therapy of mCRPCa. METHODS Three bifunctional chelates with high denticity, including the octadentate chelate DOTA, the decadentate 3p-C-DEPA and a novel dodecadentate analogue of DEPA, were synthesized and conjugated to a glutamate-urea-lysine (EuK) pharmacophore (EuK-DOTA, EuK-107 and EuK-106, respectively) to enable targeting of PSMA. The metal ion selectivity for each construct was determined by incubation at 25 °C and 95 °C with the trivalent radiometals 68Ga3+, 111In3+, 177Lu3+ and 225Ac3+. PSMA binding affinity was determined by competitive binding using LNCaP cells, while in vivo tumor targeting of the 68Ga-labeled constructs was examined by positron emission tomography (PET) in LNCaP xenograft tumor-bearing mice. RESULTS PMSA affinities (IC50 values) were 13.3 ± 0.9 nM for EuK-DOTA, 18.0 ± 3.7 nM for EuK-107 and 42.6 ± 6.6 nM for EuK-106. EuK-107 and EuK-DOTA proved to rapidly and near quantitatively complex 68Ga3+, 111In3+, 177Lu3+ and 225Ac3+ at 95 °C, with EuK-107 also rapidly complexing 111In3+ and 177Lu3+ at 25 °C. The inability of EuK-106 to chelate 177Lu3+ and 225Ac3+ suggests that size of the cavity of the macrocylic ring may be more critical than the number of donor groups for the chelation of larger radiometals. In vivo, 68Ga-EuK-107 proved to have similar uptake to 68Ga-DKFZ-PSMA-617, a theranostic ligand currently in clinical evaluation, in a PSMA positive xenograft tumor model. CONCLUSIONS The broad metal ion selectivity, good in vitro affinity for PSMA and good in vivo tumor targeting suggest that EuK-107, with the 3p-C-DEPA chelator, merits further evaluation as a theranostics construct in prostate cancer.
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Affiliation(s)
- James M Kelly
- Division of Radiopharmaceutical Sciences and MI(3), Department of Radiology, Weill Cornell Medicine, New York, NY, USA
| | - Alejandro Amor-Coarasa
- Division of Radiopharmaceutical Sciences and MI(3), Department of Radiology, Weill Cornell Medicine, New York, NY, USA
| | - Anastasia Nikolopoulou
- Division of Radiopharmaceutical Sciences and MI(3), Department of Radiology, Weill Cornell Medicine, New York, NY, USA; Citigroup Biomedical Imaging Center, Weill Cornell Medicine, New York, NY, USA
| | - Dohyun Kim
- Citigroup Biomedical Imaging Center, Weill Cornell Medicine, New York, NY, USA
| | - Clarence Williams
- Division of Radiopharmaceutical Sciences and MI(3), Department of Radiology, Weill Cornell Medicine, New York, NY, USA
| | - Shankar Vallabhajosula
- Citigroup Biomedical Imaging Center, Weill Cornell Medicine, New York, NY, USA; Division of Radiochemistry in Radiology, Weill Cornell Medicine, NY, New York, USA
| | - John W Babich
- Division of Radiopharmaceutical Sciences and MI(3), Department of Radiology, Weill Cornell Medicine, New York, NY, USA; Citigroup Biomedical Imaging Center, Weill Cornell Medicine, New York, NY, USA; Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, NY, USA.
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Abstract
OBJECTIVE This article reviews recent developments in targeted radionuclide therapy (TRT) approaches directed to malignant liver lesions, bone metastases, neuroendocrine tumors, and castrate-resistant metastatic prostate cancer and discusses challenges and opportunities in this field. CONCLUSION TRT has been employed since the first radioiodine thyroid treatment almost 75 years ago. Progress in the understanding of the complex underlying biology of cancer and advances in radiochemistry science, multimodal imaging techniques including the concept of "see and treat" within the framework of theranostics, and universal traction with the notion of precision medicine have all contributed to a resurgence of TRT.
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68
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Rowe SP, Drzezga A, Neumaier B, Dietlein M, Gorin MA, Zalutsky MR, Pomper MG. Prostate-Specific Membrane Antigen-Targeted Radiohalogenated PET and Therapeutic Agents for Prostate Cancer. J Nucl Med 2017; 57:90S-96S. [PMID: 27694179 DOI: 10.2967/jnumed.115.170175] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 08/08/2016] [Indexed: 12/16/2022] Open
Abstract
Radiohalogenated agents are often the first line of pursuit in the development of new radiopharmaceuticals-whether antibodies, peptides, or small molecules-because of their ease of synthesis, lack of substantial steric perturbation of the original affinity agent (in some cases, providing enhanced affinity), and capacity to be transformed into therapeutics (in some cases, with a mere switch of an isotope). They often provide proof of a principle before optimization for pharmacokinetics or generation of radiometallated agents, when the latter are necessary. In particular, 18F has been well integrated into normal clinical work flow in the form of 18F-FDG for oncologic imaging, with reliable daily production and distribution to sites for immediate use, without the need for on-site preparation. Here we discuss radiohalogenated versions of imaging and therapeutic agents targeting the prostate-specific membrane antigen (PSMA); these were among the first such agents to be synthesized and used clinically. PSMA is highly expressed on prostate cancer epithelial cells and is currently being extensively investigated around the world as a target for imaging and therapy of prostate cancer. Additionally, the presence of PSMA on nonprostate tumor neovasculature has opened the possibility of PSMA-targeted molecules as generalizable cancer imaging and therapy agents. We focus on 18F-labeled agents for PET, as they begin to redefine-along with the corresponding 68Ga-labeled agents discussed elsewhere in this supplement to The Journal of Nuclear Medicine-the management of prostate cancer across a variety of clinical contexts.
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Affiliation(s)
- Steven P Rowe
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Alexander Drzezga
- Department of Nuclear Medicine, University Hospital of Cologne, Cologne, Germany
| | - Bernd Neumaier
- Institute of Radiochemistry and Experimental Molecular Imaging, University Hospital of Cologne, Cologne, Germany
| | - Markus Dietlein
- Department of Nuclear Medicine, University Hospital of Cologne, Cologne, Germany
| | - Michael A Gorin
- The James Buchanan Brady Urological Institute and Department of Urology, Johns Hopkins University School of Medicine, Baltimore, Maryland; and
| | - Michael R Zalutsky
- Department of Radiology, Duke University Medical Center, Durham, North Carolina
| | - Martin G Pomper
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland
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69
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Nováková Z, Foss CA, Copeland BT, Morath V, Baranová P, Havlínová B, Skerra A, Pomper MG, Barinka C. Novel Monoclonal Antibodies Recognizing Human Prostate-Specific Membrane Antigen (PSMA) as Research and Theranostic Tools. Prostate 2017; 77:749-764. [PMID: 28247415 PMCID: PMC7061361 DOI: 10.1002/pros.23311] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 01/04/2017] [Indexed: 01/09/2023]
Abstract
BACKGROUND Prostate-specific membrane antigen (PSMA) is a validated target for the imaging and therapy of prostate cancer. Here, we report the detailed characterization of four novel murine monoclonal antibodies (mAbs) recognizing human PSMA as well as PSMA orthologs from different species. METHODS Performance of purified mAbs was assayed using a comprehensive panel of in vitro experimental setups including Western blotting, immunofluorescence, immunohistochemistry, ELISA, flow cytometry, and surface-plasmon resonance. Furthermore, a mouse xenograft model of prostate cancer was used to compare the suitability of the mAbs for in vivo applications. RESULTS All mAbs demonstrate high specificity for PSMA as documented by the lack of cross-reactivity to unrelated human proteins. The 3F11 and 1A11 mAbs bind linear epitopes spanning residues 226-243 and 271-288 of human PSMA, respectively. 3F11 is also suitable for the detection of PSMA orthologs from mouse, pig, dog, and rat in experimental setups where the denatured form of PSMA is used. 5D3 and 5B1 mAbs recognize distinct surface-exposed conformational epitopes and are useful for targeting PSMA in its native conformation. Most importantly, using a mouse xenograft model of prostate cancer we show that both the intact 5D3 and its Fab fragment are suitable for in vivo imaging. CONCLUSIONS With apparent affinities of 0.14 and 1.2 nM as determined by ELISA and flow cytometry, respectively, 5D3 has approximately 10-fold higher affinity for PSMA than the clinically validated mAb J591 and, therefore, is a prime candidate for the development of next-generation theranostics to target PSMA. Prostate 77:749-764, 2017. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Zora Nováková
- Laboratory of Structural Biology, Institute of Biotechnology, Czech Academy of Sciences, Vestec, Czech Republic
| | - Catherine A. Foss
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Benjamin T. Copeland
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Volker Morath
- Munich Center for Integrated Protein Science (CIPS-M) and Lehrstuhl für Biologische Chemie, Technische Universität München, Freising-Weihenstephan, Germany
| | - Petra Baranová
- Laboratory of Structural Biology, Institute of Biotechnology, Czech Academy of Sciences, Vestec, Czech Republic
| | - Barbora Havlínová
- Laboratory of Structural Biology, Institute of Biotechnology, Czech Academy of Sciences, Vestec, Czech Republic
| | - Arne Skerra
- Munich Center for Integrated Protein Science (CIPS-M) and Lehrstuhl für Biologische Chemie, Technische Universität München, Freising-Weihenstephan, Germany
| | - Martin G. Pomper
- The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Cyril Barinka
- Laboratory of Structural Biology, Institute of Biotechnology, Czech Academy of Sciences, Vestec, Czech Republic
- Correspondence to: Dr. Cyril Barinka, Institute of Biotechnology CAS, v.v.i., Laboratory of Structural Biology, Prumyslova 595, 25250 Vestec, Czech Republic.
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Lutetium-177-labelled anti-prostate-specific membrane antigen antibody and ligands for the treatment of metastatic castrate-resistant prostate cancer: a systematic review and meta-analysis. Prostate Cancer Prostatic Dis 2017; 20:352-360. [DOI: 10.1038/pcan.2017.23] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 03/04/2017] [Accepted: 03/16/2017] [Indexed: 11/08/2022]
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71
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Kratochwil C, Bruchertseifer F, Rathke H, Bronzel M, Apostolidis C, Weichert W, Haberkorn U, Giesel FL, Morgenstern A. Targeted α-Therapy of Metastatic Castration-Resistant Prostate Cancer with 225Ac-PSMA-617: Dosimetry Estimate and Empiric Dose Finding. J Nucl Med 2017; 58:1624-1631. [PMID: 28408529 DOI: 10.2967/jnumed.117.191395] [Citation(s) in RCA: 322] [Impact Index Per Article: 46.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 04/03/2017] [Indexed: 11/16/2022] Open
Abstract
The aim of this study was to develop a treatment protocol for 225Ac-PSMA-617 α-radiation therapy in advanced-stage, metastatic castration-resistant prostate cancer patients with prostate-specific membrane antigen (PSMA)-positive tumor phenotype. Methods: A dosimetry estimate was calculated on the basis of time-activity curves derived from serially obtained 177Lu-PSMA-617 scans extrapolated to the physical half-life of 225Ac, assuming instant decay of unstable daughter nuclides. Salvage therapies empirically conducted with 50 (n = 4), 100 (n = 4), 150 (n = 2), and 200 kBq/kg (n = 4) of 225Ac-PSMA-617 were evaluated retrospectively regarding toxicity and treatment response. Eight of 14 patients received further cycles in either 2- or 4-mo intervals with identical or deescalated activities. Results: Dosimetry estimates for 1 MBq of 225Ac-PSMA-617 assuming a relative biologic effectiveness of 5 revealed mean doses of 2.3 Sv for salivary glands, 0.7 Sv for kidneys, and 0.05 Sv for red marrow that are composed of 99.4% α, 0.5% β, and 0.1% photon radiation, respectively. In clinical application, severe xerostomia became the dose-limiting toxicity if treatment activity exceeded 100 kBq/kg per cycle. At 100 kBq/kg, the duration of prostate-specific antigen decline was less than 4 mo, but if therapy was repeated every 2 mo patients experienced additive antitumor effects. Treatment activities of 50 kBq/kg were without toxicity but induced insufficient antitumor response in these high-tumor-burden patients. Remarkable antitumor activity by means of objective radiologic response or tumor marker decline was observed in 9 of 11 evaluable patients. Conclusion: For advanced-stage patients, a treatment activity of 100 kBq/kg of 225Ac-PSMA-617 per cycle repeated every 8 wk presents a reasonable trade-off between toxicity and biochemical response.
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Affiliation(s)
- Clemens Kratochwil
- Department of Nuclear Medicine, University Hospital Heidelberg, Heidelberg, Germany
| | - Frank Bruchertseifer
- Directorate for Nuclear Safety and Security, European Commission, Joint Research Centre, Karlsruhe, Germany
| | - Hendrik Rathke
- Department of Nuclear Medicine, University Hospital Heidelberg, Heidelberg, Germany
| | | | - Christos Apostolidis
- Directorate for Nuclear Safety and Security, European Commission, Joint Research Centre, Karlsruhe, Germany
| | - Wilko Weichert
- Institute of Pathology, University Hospital at Technical University Munich, Munich, Germany; and
| | - Uwe Haberkorn
- Department of Nuclear Medicine, University Hospital Heidelberg, Heidelberg, Germany.,Cooperation Unit Nuclear Medicine, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Frederik L Giesel
- Department of Nuclear Medicine, University Hospital Heidelberg, Heidelberg, Germany
| | - Alfred Morgenstern
- Directorate for Nuclear Safety and Security, European Commission, Joint Research Centre, Karlsruhe, Germany
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72
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Gourni E, Henriksen G. Metal-Based PSMA Radioligands. Molecules 2017; 22:molecules22040523. [PMID: 28338640 PMCID: PMC6154343 DOI: 10.3390/molecules22040523] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 03/13/2017] [Accepted: 03/18/2017] [Indexed: 12/20/2022] Open
Abstract
Prostate cancer is one of the most common malignancies for which great progress has been made in identifying appropriate molecular targets that would enable efficient in vivo targeting for imaging and therapy. The type II integral membrane protein, prostate specific membrane antigen (PSMA) is overexpressed on prostate cancer cells in proportion to the stage and grade of the tumor progression, especially in androgen-independent, advanced and metastatic disease, rendering it a promising diagnostic and/or therapeutic target. From the perspective of nuclear medicine, PSMA-based radioligands may significantly impact the management of patients who suffer from prostate cancer. For that purpose, chelating-based PSMA-specific ligands have been labeled with various diagnostic and/or therapeutic radiometals for single-photon-emission tomography (SPECT), positron-emission-tomography (PET), radionuclide targeted therapy as well as intraoperative applications. This review focuses on the development and further applications of metal-based PSMA radioligands.
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Affiliation(s)
- Eleni Gourni
- Institute of Basic Medical Sciences, University of Oslo, Oslo 0372, Norway.
- Norwegian Medical Cyclotron Centre Ltd., P.O. Box 4950 Nydalen, Oslo 0424, Norway.
| | - Gjermund Henriksen
- Institute of Basic Medical Sciences, University of Oslo, Oslo 0372, Norway.
- Norwegian Medical Cyclotron Centre Ltd., P.O. Box 4950 Nydalen, Oslo 0424, Norway.
- Institute of Physics, University of Oslo, Oslo 0317, Norway.
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73
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Pereira E, do Quental L, Palma E, Oliveira MC, Mendes F, Raposinho P, Correia I, Lavrado J, Di Maria S, Belchior A, Vaz P, Santos I, Paulo A. Evaluation of Acridine Orange Derivatives as DNA-Targeted Radiopharmaceuticals for Auger Therapy: Influence of the Radionuclide and Distance to DNA. Sci Rep 2017; 7:42544. [PMID: 28211920 PMCID: PMC5304164 DOI: 10.1038/srep42544] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 01/09/2017] [Indexed: 01/01/2023] Open
Abstract
A new family of 99mTc(I)- tricarbonyl complexes and 125I-heteroaromatic compounds bearing an acridine orange (AO) DNA targeting unit was evaluated for Auger therapy. Characterization of the DNA interaction, performed with the non-radioactive Re and 127I congeners, confirmed that all compounds act as DNA intercalators. Both classes of compounds induce double strand breaks (DSB) in plasmid DNA but the extent of DNA damage is strongly dependent on the linker between the Auger emitter (99mTc or 125I) and the AO moiety. The in vitro evaluation was complemented with molecular docking studies and Monte Carlo simulations of the energy deposited at the nanometric scale, which corroborated the experimental data. Two of the tested compounds, 125I-C5 and 99mTc-C3, place the corresponding radionuclide at similar distances to DNA and produce comparable DSB yields in plasmid and cellular DNA. These results provide the first evidence that 99mTc can induce DNA damage with similar efficiency to that of 125I, when both are positioned at comparable distances to the double helix. Furthermore, the high nuclear retention of 99mTc-C3 in tumoral cells suggests that 99mTc-labelled AO derivatives are more promising for the design of Auger-emitting radiopharmaceuticals than the 125I-labelled congeners.
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Affiliation(s)
- Edgar Pereira
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal
| | - Letícia do Quental
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal
| | - Elisa Palma
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal.,Centro Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1049-001 Lisboa, Portugal
| | - Maria Cristina Oliveira
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal
| | - Filipa Mendes
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal
| | - Paula Raposinho
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal
| | - Isabel Correia
- Centro Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1049-001 Lisboa, Portugal
| | - João Lavrado
- iMed.ULisboa, Faculdade de Farmácia, Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal
| | - Salvatore Di Maria
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal
| | - Ana Belchior
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal
| | - Pedro Vaz
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal
| | - Isabel Santos
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal
| | - António Paulo
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal
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Scarpa L, Buxbaum S, Kendler D, Fink K, Bektic J, Gruber L, Decristoforo C, Uprimny C, Lukas P, Horninger W, Virgolini I. The 68Ga/ 177Lu theragnostic concept in PSMA targeting of castration-resistant prostate cancer: correlation of SUV max values and absorbed dose estimates. Eur J Nucl Med Mol Imaging 2017; 44:788-800. [PMID: 28083690 DOI: 10.1007/s00259-016-3609-9] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 12/23/2016] [Indexed: 12/25/2022]
Abstract
INTRODUCTION A targeted theragnostic approach based on increased expression of prostate-specific membrane antigen (PSMA) on PC cells is an attractive treatment option for patients with metastatic castration-resistant prostate cancer (mCRPC). METHODS Ten consecutive mCRPC patients were selected for 177Lu-PSMA617 therapy on the basis of PSMA-targeted 68Ga-PSMA-HBED-CC PET/CT diagnosis showing extensive and progressive tumour load. Following dosimetry along with the first therapy cycle restaging (68Ga-PSMA-HBED-CC and 18F-NaF PET/CT) was performed after 2 and 3 therapy cycles (each 6.1 ± 0.3 GBq, range 5.4-6.5 GBq) given intravenously over 30 minutes, 9 ± 1 weeks apart. PET/CT scans were compared to 177Lu-PSMA617 24-hour whole-body scans and contrast-enhanced dual-phase CT. Detailed comparison of SUVmax values and absorbed tumour doses was performed. RESULTS 177Lu-PSMA617 dosimetry indicated high tumour doses for skeletal (3.4 ± 1.9 Gy/GBq; range 1.1-7.2 Gy/GBq), lymph node (2.6 ± 0.4 Gy/GBq; range 2.3-2.9 Gy/GBq) as well as liver (2.4 ± 0.8 Gy/GBq; range 1.7-3.3 Gy/GBq) metastases whereas the dose for tissues/organs was acceptable in all patients for an intention-to-treat activity of 18 ± 0.3 GBq. Three patients showed partial remission, three mixed response, one stable and three progressive disease. Decreased 177Lu-PSMA617 and 68Ga-PSMA-HBED-CC uptake (mean SUVmax values 20.2 before and 15.0 after 2 cycles and 11.5 after 3 cycles, p < 0.05) was found in 41/54 skeletal lesions, 12/13 lymph node metastases, 3/5 visceral metastases and 4/4 primary PC lesions. CONCLUSION Due to substantial individual variance, dosimetry is mandatory for a patient-specific approach following 177Lu-PSMA617 therapy. Higher activities and/or shorter treatment intervals should be applied in a larger prospective study.
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Affiliation(s)
- Lorenza Scarpa
- Department of Nuclear Medicine, Medical University Innsbruck, Anichstraße 35, A-6020, Innsbruck, Austria
| | - Sabine Buxbaum
- Department of Nuclear Medicine, Medical University Innsbruck, Anichstraße 35, A-6020, Innsbruck, Austria
| | - Dorota Kendler
- Department of Nuclear Medicine, Medical University Innsbruck, Anichstraße 35, A-6020, Innsbruck, Austria
| | - Katharina Fink
- Department of Nuclear Medicine, Medical University Innsbruck, Anichstraße 35, A-6020, Innsbruck, Austria.,Department of Radiotherapy / Radiation Oncology, Medical University of Innsbruck, Innsbruck, Austria
| | - Jasmin Bektic
- Department of Urology, Medical University of Innsbruck, Innsbruck, Austria
| | - Leonhard Gruber
- Department of Radiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Clemens Decristoforo
- Department of Nuclear Medicine, Medical University Innsbruck, Anichstraße 35, A-6020, Innsbruck, Austria
| | - Christian Uprimny
- Department of Nuclear Medicine, Medical University Innsbruck, Anichstraße 35, A-6020, Innsbruck, Austria
| | - Peter Lukas
- Department of Radiotherapy / Radiation Oncology, Medical University of Innsbruck, Innsbruck, Austria
| | - Wolfgang Horninger
- Department of Urology, Medical University of Innsbruck, Innsbruck, Austria
| | - Irene Virgolini
- Department of Nuclear Medicine, Medical University Innsbruck, Anichstraße 35, A-6020, Innsbruck, Austria.
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75
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Slastnikova TA, Rosenkranz AA, Morozova NB, Vorontsova MS, Petriev VM, Lupanova TN, Ulasov AV, Zalutsky MR, Yakubovskaya RI, Sobolev AS. Preparation, cytotoxicity, and in vivo antitumor efficacy of 111In-labeled modular nanotransporters. Int J Nanomedicine 2017; 12:395-410. [PMID: 28138237 PMCID: PMC5238804 DOI: 10.2147/ijn.s125359] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
PURPOSE Modular nanotransporters (MNTs) are a polyfunctional platform designed to achieve receptor-specific delivery of short-range therapeutics into the cell nucleus by receptor-mediated endocytosis, endosome escape, and targeted nuclear transport. This study evaluated the potential utility of the MNT platform in tandem with Auger electron emitting 111In for cancer therapy. METHODS Three MNTs developed to target either melanocortin receptor-1 (MC1R), folate receptor (FR), or epidermal growth factor receptor (EGFR) that are overexpressed on cancer cells were modified with p-SCN-Bn-NOTA and then labeled with 111In in high specific activity. Cytotoxicity of the 111In-labeled MNTs was evaluated on cancer cell lines bearing the appropriate receptor target (FR: HeLa, SK-OV-3; EGFR: A431, U87MG.wtEGFR; and MC1R: B16-F1). In vivo micro-single-photon emission computed tomography/computed tomography imaging and antitumor efficacy studies were performed with intratumoral injection of MC1R-targeted 111In-labeled MNT in B16-F1 melanoma tumor-bearing mice. RESULTS The three NOTA-MNT conjugates were labeled with a specific activity of 2.7 GBq/mg with nearly 100% yield, allowing use without subsequent purification. The cytotoxicity of 111In delivered by these MNTs was greatly enhanced on receptor-expressing cancer cells compared with 111In nontargeted control. In mice with B16-F1 tumors, prolonged retention of 111In by serial imaging and significant tumor growth delay (82% growth inhibition) were found. CONCLUSION The specific in vitro cytotoxicity, prolonged tumor retention, and therapeutic efficacy of MC1R-targeted 111In-NOTA-MNT suggest that this Auger electron emitting conjugate warrants further evaluation as a locally delivered radiotherapeutic, such as for ocular melanoma brachytherapy. Moreover, the high cytotoxicity observed with FR- and EGFR-targeted 111In-NOTA-MNT suggests further applications of the MNT delivery strategy should be explored.
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Affiliation(s)
- Tatiana A Slastnikova
- Laboratory of Molecular Genetics of Intracellular Transport, Institute of Gene Biology, Russian Academy of Sciences
| | - Andrey A Rosenkranz
- Laboratory of Molecular Genetics of Intracellular Transport, Institute of Gene Biology, Russian Academy of Sciences
- Department of Biophysics, Biological Faculty, Lomonosov Moscow State University
| | - Natalia B Morozova
- Department of Anticancer Therapy Modifiers and Protectors, Moscow Hertsen Research Institute of Oncology, Russian Ministry of Health Care, Moscow
| | - Maria S Vorontsova
- Department of Anticancer Therapy Modifiers and Protectors, Moscow Hertsen Research Institute of Oncology, Russian Ministry of Health Care, Moscow
| | - Vasiliy M Petriev
- National Medical Research Radiological Center, Russian Ministry of Health Care, Obninsk, Moscow Region
- Department of Nuclear Medicine, National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Moscow, Russia
| | - Tatiana N Lupanova
- Laboratory of Molecular Genetics of Intracellular Transport, Institute of Gene Biology, Russian Academy of Sciences
| | - Alexey V Ulasov
- Laboratory of Molecular Genetics of Intracellular Transport, Institute of Gene Biology, Russian Academy of Sciences
| | - Michael R Zalutsky
- Department of Radiology, Duke University Medical Center, Durham, NC, USA
| | - Raisa I Yakubovskaya
- Department of Anticancer Therapy Modifiers and Protectors, Moscow Hertsen Research Institute of Oncology, Russian Ministry of Health Care, Moscow
| | - Alexander S Sobolev
- Laboratory of Molecular Genetics of Intracellular Transport, Institute of Gene Biology, Russian Academy of Sciences
- Department of Biophysics, Biological Faculty, Lomonosov Moscow State University
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76
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Oliveira AA, Franco LL, dos Santos RG, Perdigão GMC, da Silva JG, Souza-Fagundes EM, Beraldo H. Neutron activation of In(iii) complexes with thiosemicarbazones leads to the production of potential radiopharmaceuticals for the treatment of breast cancer. NEW J CHEM 2017. [DOI: 10.1039/c7nj01547j] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
114mIn(iii) complexes with 2-acetylpyridine-derived thiosemicarbazones show potent cytotoxic activity.
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Affiliation(s)
- Alexandre A. Oliveira
- Departamento de Química
- Universidade Federal de Minas Gerais
- 31270-901 Belo Horizonte
- Brazil
| | - Lucas L. Franco
- Departamento de Química
- Universidade Federal de Minas Gerais
- 31270-901 Belo Horizonte
- Brazil
| | - Raquel G. dos Santos
- Centro de Desenvolvimento da Tecnologia Nuclear
- CDTN
- 31270-901 Belo Horizonte
- Brazil
| | - Gabriele M. C. Perdigão
- Departamento de Fisiologia e Biofísica
- Universidade Federal de Minas Gerais
- 31270-901 Belo Horizonte
- Brazil
| | - Jeferson G. da Silva
- Departamento de Farmácia
- Universidade Federal de Juiz de Fora
- Campus Governador Valadares
- 35010-177 Governador Valadares
- Brazil
| | - Elaine M. Souza-Fagundes
- Departamento de Fisiologia e Biofísica
- Universidade Federal de Minas Gerais
- 31270-901 Belo Horizonte
- Brazil
| | - Heloisa Beraldo
- Departamento de Química
- Universidade Federal de Minas Gerais
- 31270-901 Belo Horizonte
- Brazil
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77
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Banerjee SR, Foss CA, Horhota A, Pullambhatla M, McDonnell K, Zale S, Pomper MG. 111In- and IRDye800CW-Labeled PLA-PEG Nanoparticle for Imaging Prostate-Specific Membrane Antigen-Expressing Tissues. Biomacromolecules 2016; 18:201-209. [PMID: 28001364 DOI: 10.1021/acs.biomac.6b01485] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Targeted delivery of drug-encapsulated nanoparticles is a promising new approach to safe and effective therapeutics for cancer. Here we investigate the pharmacokinetics and biodistribution of a prostate-specific membrane antigen (PSMA)-targeted nanoparticle based on a poly(lactic acid)-polyethylene glycol copolymer by utilizing single photon emission computed tomography (SPECT) and fluorescence imaging of a low-molecular-weight, PSMA-targeting moiety attached to the surface and oriented toward the outside environment. Tissue biodistribution of the radioactive, PSMA-targeted nanoparticles in mice containing PSMA(+) PC3 PIP and PSMA(-) PC3 flu (control) tumors demonstrated similar accumulation compared to the untargeted particles within all tissues except for the tumor and liver by 96 h postinjection. For PSMA(+) PC3 PIP tumor, the targeted nanoparticle demonstrated retention of 6.58% injected dose (ID)/g at 48 h and remained nearly at that level out to 96 h, whereas the untargeted nanoparticle showed a 48 h retention of 8.17% ID/g followed by a significant clearance to 2.37% ID/g at 96 h (P < 0.02). On the other hand, for control tumor, both targeted and untargeted particles displayed similar 48 h retentions and rates of clearance over 96 h. Ex vivo microscopic analysis with near-infrared versions of the nanoparticles indicated retention within PSMA(+) tumor epithelial cells as well as tumor-associated macrophages for targeted particles and primarily macrophage-associated uptake for the untargeted particles. Retention in control tumor was primarily associated with tumor vasculature and macrophages. The data demonstrate the utility of radioimaging to assess nanoparticle biodistribution and suggest that active targeting has a modest positive effect on tumor localization of PSMA-targeted PLA-PEG nanoparticles that have been derivatized for imaging.
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Affiliation(s)
- Sangeeta R Banerjee
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions , Baltimore, Maryland 21287, United States
| | - Catherine A Foss
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions , Baltimore, Maryland 21287, United States
| | - Allen Horhota
- BIND Therapeutics, Cambridge, Massachusetts 02139, United States
| | - Mrudula Pullambhatla
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions , Baltimore, Maryland 21287, United States
| | - Kevin McDonnell
- BIND Therapeutics, Cambridge, Massachusetts 02139, United States
| | - Stephen Zale
- BIND Therapeutics, Cambridge, Massachusetts 02139, United States
| | - Martin G Pomper
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins Medical Institutions , Baltimore, Maryland 21287, United States
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Evans JC, Malhotra M, Cryan JF, O'Driscoll CM. The therapeutic and diagnostic potential of the prostate specific membrane antigen/glutamate carboxypeptidase II (PSMA/GCPII) in cancer and neurological disease. Br J Pharmacol 2016; 173:3041-3079. [PMID: 27526115 PMCID: PMC5056232 DOI: 10.1111/bph.13576] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2016] [Revised: 07/08/2016] [Accepted: 07/25/2016] [Indexed: 12/11/2022] Open
Abstract
Prostate specific membrane antigen (PSMA) otherwise known as glutamate carboxypeptidase II (GCPII) is a membrane bound protein that is highly expressed in prostate cancer and in the neovasculature of a wide variety of tumours including glioblastomas, breast and bladder cancers. This protein is also involved in a variety of neurological diseases including schizophrenia and ALS. In recent years, there has been a surge in the development of both diagnostics and therapeutics that take advantage of the expression and activity of PSMA/GCPII. These include gene therapy, immunotherapy, chemotherapy and radiotherapy. In this review, we discuss the biological roles that PSMA/GCPII plays, both in normal and diseased tissues, and the current therapies exploiting its activity that are at the preclinical stage. We conclude by giving an expert opinion on the future direction of PSMA/GCPII based therapies and diagnostics and hurdles that need to be overcome to make them effective and viable.
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Affiliation(s)
- James C Evans
- Pharmacodelivery Group, School of Pharmacy, University College Cork, Cork, Ireland
| | - Meenakshi Malhotra
- Pharmacodelivery Group, School of Pharmacy, University College Cork, Cork, Ireland
| | - John F Cryan
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland
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Li M, Banerjee SR, Zheng C, Pomper MG, Barman I. Ultrahigh affinity Raman probe for targeted live cell imaging of prostate cancer. Chem Sci 2016; 7:6779-6785. [PMID: 28451123 PMCID: PMC5356002 DOI: 10.1039/c6sc01739h] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 07/14/2016] [Indexed: 01/29/2023] Open
Abstract
Precise visualization of tumor margins with characterization of microscopic tumor invasion are unmet needs in prostate oncology that demand approaches with high sensitivity and specificity. To address those needs we report surface-enhanced Raman scattering (SERS) based optical imaging for prostate cancer using a combination of live cell Raman microscopy, optimally engineered SERS tags and a urea-based small-molecule inhibitor of prostate-specific membrane antigen (PSMA) as a targeting moiety. We develop gold nanostar based SERS agents that offer ultrahigh binding affinity to PSMA with nearly four orders of magnitude lower IC50 values in relation to existing clinical imaging agents. This combination enables selective recognition of prostate cancer cells, and facilitates quantitative and photostable Raman measurements. Using Raman microscopy to analyze phenotypically similar prostate cancer cell lines differing only in PSMA expression, we demonstrate facile, site-selective recognition using as low as 20 pM of the SERS agent for imaging, opening the door for spectroscopic detection of prostate and other PSMA-expressing tumors in vivo.
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Affiliation(s)
- Ming Li
- Department of Mechanical Engineering , Johns Hopkins University , Baltimore , Maryland 21218 , USA . ;
| | - Sangeeta Ray Banerjee
- The Sidney Kimmel Comprehensive Cancer Center , Johns Hopkins University School of Medicine , Baltimore , Maryland 21287 , USA .
- The Russell H. Morgan Department of Radiology and Radiological Sciences , Johns Hopkins University School of Medicine , Baltimore , Maryland 21287 , USA
| | - Chao Zheng
- Department of Mechanical Engineering , Johns Hopkins University , Baltimore , Maryland 21218 , USA . ;
- Department of Breast Surgery , The Second Hospital of Shandong University , Jinan , Shandong 25000 , China
| | - Martin G Pomper
- The Sidney Kimmel Comprehensive Cancer Center , Johns Hopkins University School of Medicine , Baltimore , Maryland 21287 , USA .
- The Russell H. Morgan Department of Radiology and Radiological Sciences , Johns Hopkins University School of Medicine , Baltimore , Maryland 21287 , USA
| | - Ishan Barman
- Department of Mechanical Engineering , Johns Hopkins University , Baltimore , Maryland 21218 , USA . ;
- The Sidney Kimmel Comprehensive Cancer Center , Johns Hopkins University School of Medicine , Baltimore , Maryland 21287 , USA .
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80
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Pillai MRA, Nanabala R, Joy A, Sasikumar A, Russ Knapp FF. Radiolabeled enzyme inhibitors and binding agents targeting PSMA: Effective theranostic tools for imaging and therapy of prostate cancer. Nucl Med Biol 2016; 43:692-720. [PMID: 27589333 DOI: 10.1016/j.nucmedbio.2016.08.006] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2016] [Revised: 08/09/2016] [Accepted: 08/09/2016] [Indexed: 12/14/2022]
Abstract
Because of the broad incidence, morbidity and mortality associated with prostate-derived cancer, the development of more effective new technologies continues to be an important goal for the accurate detection and treatment of localized prostate cancer, lymphatic involvement and metastases. Prostate-specific membrane antigen (PSMA; Glycoprotein II) is expressed in high levels on prostate-derived cells and is an important target for visualization and treatment of prostate cancer. Radiolabeled peptide targeting technologies have rapidly evolved over the last decade and have focused on the successful development of radiolabeled small molecules that act as inhibitors to the binding of the N-acetyl-l-aspartyl-l-glutamate (NAAG) substrate to the PSMA molecule. A number of radiolabeled PSMA inhibitors have been described in the literature and labeled with SPECT, PET and therapeutic radionuclides. Clinical studies with these agents have demonstrated the improved potential of PSMA-targeted PET imaging agents to detect metastatic prostate cancer in comparison with conventional imaging technologies. Although many of these agents have been evaluated in humans, by far the most extensive clinical literature has described use of the 68Ga and 177Lu agents. This review describes the design and development of these agents, with a focus on the broad clinical introduction of PSMA targeting motifs labeled with 68Ga for PET-CT imaging and 177Lu for therapy. In particular, because of availability from the long-lived 68Ge (T1/2=270days)/68Ga (T1/2=68min) generator system and increasing availability of PET-CT, the 68Ga-labeled PSMA targeted agent is receiving widespread interest and is one of the fastest growing radiopharmaceuticals for PET-CT imaging.
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Affiliation(s)
| | - Raviteja Nanabala
- KIMS DDNMRC PET Scans, KIMS Hospital, Trivandrum, Kerala, India, 691601
| | - Ajith Joy
- Molecular Group of Companies, Puthuvype, Ernakulam, Kerala, 682508, India
| | - Arun Sasikumar
- KIMS DDNMRC PET Scans, KIMS Hospital, Trivandrum, Kerala, India, 691601
| | - Furn F Russ Knapp
- Emeritus, Medical Radioisotope Program, Oak Ridge National Laboratory, Oak Ridge, TN, USA, 37830
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Kiess AP, Minn I, Vaidyanathan G, Hobbs RF, Josefsson A, Shen C, Brummet M, Chen Y, Choi J, Koumarianou E, Baidoo K, Brechbiel MW, Mease RC, Sgouros G, Zalutsky MR, Pomper MG. (2S)-2-(3-(1-Carboxy-5-(4-211At-Astatobenzamido)Pentyl)Ureido)-Pentanedioic Acid for PSMA-Targeted α-Particle Radiopharmaceutical Therapy. J Nucl Med 2016; 57:1569-1575. [PMID: 27230930 DOI: 10.2967/jnumed.116.174300] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 04/11/2016] [Indexed: 12/22/2022] Open
Abstract
Alpha-particle emitters have a high linear energy transfer and short range, offering the potential for treating micrometastases while sparing normal tissues. We developed a urea-based, 211At-labeled small molecule targeting prostate-specific membrane antigen (PSMA) for the treatment of micrometastases due to prostate cancer (PC). METHODS PSMA-targeted (2S)-2-(3-(1-carboxy-5-(4-211At-astatobenzamido)pentyl)ureido)-pentanedioic acid (211At- 6: ) was synthesized. Cellular uptake and clonogenic survival were tested in PSMA-positive (PSMA+) PC3 PIP and PSMA-negative (PSMA-) PC3 flu human PC cells after 211At- 6: treatment. The antitumor efficacy of 211At- 6: was evaluated in mice bearing PSMA+ PC3 PIP and PSMA- PC3 flu flank xenografts at a 740-kBq dose and in mice bearing PSMA+, luciferase-expressing PC3-ML micrometastases. Biodistribution was determined in mice bearing PSMA+ PC3 PIP and PSMA- PC3 flu flank xenografts. Suborgan distribution was evaluated using α-camera images, and microscale dosimetry was modeled. Long-term toxicity was assessed in mice for 12 mo. RESULTS 211At- 6: treatment resulted in PSMA-specific cellular uptake and decreased clonogenic survival in PSMA+ PC3 PIP cells and caused significant tumor growth delay in PSMA+ PC3 PIP flank tumors. Significantly improved survival was achieved in the newly developed PSMA+ micrometastatic PC model. Biodistribution showed uptake of 211At- 6: in PSMA+ PC3 PIP tumors and in kidneys. Microscale kidney dosimetry based on α-camera images and a nephron model revealed hot spots in the proximal renal tubules. Long-term toxicity studies confirmed that the dose-limiting toxicity was late radiation nephropathy. CONCLUSION PSMA-targeted 211At- 6: α-particle radiotherapy yielded significantly improved survival in mice bearing PC micrometastases after systemic administration. 211At- 6: also showed uptake in renal proximal tubules resulting in late nephrotoxicity, highlighting the importance of long-term toxicity studies and microscale dosimetry.
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Affiliation(s)
- Ana P Kiess
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Il Minn
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Ganesan Vaidyanathan
- Department of Radiology, Duke University Medical Center, Durham, North Carolina; and
| | - Robert F Hobbs
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Anders Josefsson
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Colette Shen
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Mary Brummet
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Ying Chen
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Jaeyeon Choi
- Department of Radiology, Duke University Medical Center, Durham, North Carolina; and
| | - Eftychia Koumarianou
- Department of Radiology, Duke University Medical Center, Durham, North Carolina; and
| | - Kwamena Baidoo
- Center for Cancer Research, National Cancer Institute, Bethesda, Maryland
| | - Martin W Brechbiel
- Center for Cancer Research, National Cancer Institute, Bethesda, Maryland
| | - Ronnie C Mease
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - George Sgouros
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Michael R Zalutsky
- Department of Radiology, Duke University Medical Center, Durham, North Carolina; and
| | - Martin G Pomper
- Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland
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82
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Zukotynski K, Jadvar H, Capala J, Fahey F. Targeted Radionuclide Therapy: Practical Applications and Future Prospects. BIOMARKERS IN CANCER 2016; 8:35-8. [PMID: 27226737 PMCID: PMC4874742 DOI: 10.4137/bic.s31804] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 10/13/2015] [Accepted: 10/17/2015] [Indexed: 12/17/2022]
Abstract
In recent years, there has been a proliferation in the development of targeted radionuclide cancer therapy. It is now possible to use baseline clinical and imaging assessments to determine the most effective therapy and to tailor this therapy during the course of treatment based on radiation dosimetry and tumor response. Although this personalized approach to medicine has the advantage of maximizing therapeutic effect while limiting toxicity, it can be challenging to implement and expensive. Further, in order to use targeted radionuclide therapy effectively, there is a need for multidisciplinary awareness, education, and collaboration across the scientific, industrial, and medical communities. Even more important, there is a growing understanding that combining radiopharmaceuticals with conventional treatment such as chemotherapy and external beam radiotherapy may limit patient morbidity while improving survival. Developments in radiopharmaceuticals as biomarkers capable of predicting therapeutic response and targeting disease are playing a central role in medical research. Adoption of a practical approach to manufacturing and delivering radiopharmaceuticals, assessing patient eligibility, optimizing post-therapy follow-up, and addressing reimbursement issues will be essential for their success.
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Affiliation(s)
- Katherine Zukotynski
- Departments of Radiology and Medicine, McMaster University, Hamilton, ON, Canada
| | - Hossein Jadvar
- Department of Radiology, University of Southern California, Los Angeles, CA, USA
| | - Jacek Capala
- Division of Cancer Treatment and Diagnosis, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Frederic Fahey
- Department of Radiology, Boston Children's Hospital, Boston, MA, USA.; Harvard Medical School, Boston, MA, USA
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83
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Lee BQ, Nikjoo H, Ekman J, Jönsson P, Stuchbery AE, Kibédi T. A stochastic cascade model for Auger-electron emitting radionuclides. Int J Radiat Biol 2016; 92:641-653. [PMID: 27010453 DOI: 10.3109/09553002.2016.1153810] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
To benchmark a Monte Carlo model of the Auger cascade that has been developed at the Australian National University (ANU) against the literature data. The model is applicable to any Auger-electron emitting radionuclide with nuclear structure data in the format of the Evaluated Nuclear Structure Data File (ENSDF). Schönfeld's algorithms and the BrIcc code were incorporated to obtain initial vacancy distributions due to electron capture (EC) and internal conversion (IC), respectively. Atomic transition probabilities were adopted from the Evaluated Atomic Data Library (EADL) for elements with atomic number, Z = 1-100. Atomic transition energies were evaluated using a relativistic Dirac-Fock method. An energy-restriction protocol was implemented to eliminate energetically forbidden transitions from the simulations. Calculated initial vacancy distributions and average energy spectra of 123I, 124I, and 125I were compared with the literature data. In addition, simulated kinetic energy spectra and frequency distributions of the number of emitted electrons and photons of the three iodine radionuclides are presented. Some examples of radiation spectra of individual decays are also given. Good agreement with the published data was achieved except for the outer-shell Auger and Coster-Kronig transitions. Nevertheless, the model needs to be compared with experimental data in a future study.
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Affiliation(s)
- Boon Q Lee
- a Department of Nuclear Physics , Research School of Physics and Engineering, The Australian National University , Canberra , Australia
| | - Hooshang Nikjoo
- b Department of Oncology-Pathology , Karolinska Institutet , Stockholm , Sweden
| | - Jörgen Ekman
- c Materials Science and Applied Mathematics , Malmö University , Malmö , Sweden
| | - Per Jönsson
- c Materials Science and Applied Mathematics , Malmö University , Malmö , Sweden
| | - Andrew E Stuchbery
- a Department of Nuclear Physics , Research School of Physics and Engineering, The Australian National University , Canberra , Australia
| | - Tibor Kibédi
- a Department of Nuclear Physics , Research School of Physics and Engineering, The Australian National University , Canberra , Australia
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84
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Kim JS. Combination Radioimmunotherapy Approaches and Quantification of Immuno-PET. Nucl Med Mol Imaging 2016; 50:104-11. [PMID: 27275358 PMCID: PMC4870465 DOI: 10.1007/s13139-015-0392-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 12/18/2015] [Accepted: 12/23/2015] [Indexed: 11/30/2022] Open
Abstract
Monoclonal antibodies (mAbs), which play a prominent role in cancer therapy, can interact with specific antigens on cancer cells, thereby enhancing the patient's immune response via various mechanisms, or mAbs can act against cell growth factors and, thereby, arrest the proliferation of tumor cells. Radionuclide-labeled mAbs, which are used in radioimmunotherapy (RIT), are effective for cancer treatment because tumor associated-mAbs linked to cytotoxic radionuclides can selectively bind to tumor antigens and release targeted cytotoxic radiation. Immunological positron emission tomography (immuno-PET), which is the combination of PET with mAb, is an attractive option for improving tumor detection and mAb quantification. However, RIT remains a challenge because of the limited delivery of mAb into tumors. The transport and uptake of mAb into tumors is slow and heterogeneous. The tumor microenvironment contributed to the limited delivery of the mAb. During the delivery process of mAb to tumor, mechanical drug resistance such as collagen distribution or physiological drug resistance such as high intestinal pressure or absence of lymphatic vessel would be the limited factor of mAb delivery to the tumor at a potentially lethal mAb concentration. When α-emitter-labeled mAbs were used, deeper penetration of α-emitter-labeled mAb inside tumors was more important because of the short range of the α emitter. Therefore, combination therapy strategies aimed at improving mAb tumor penetration and accumulation would be beneficial for maximizing their therapeutic efficacy against solid tumors.
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Affiliation(s)
- Jin Su Kim
- />Molecular Imaging Research Center, Korea Institute of Radiological and Medical Sciences, 75 Nowon-Gil, Gongneung-Dong, Nowon-Gu, Seoul, 01812 Korea
- />Korea Drug Development Platform using Radio-Isotope(KDePRI), Seoul, Korea
- />Radiologcial and Medico-Oncological Sciences, University of Science and Technology (UST), Seoul, Korea
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85
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Kiess AP, Banerjee SR, Mease RC, Rowe SP, Rao A, Foss CA, Chen Y, Yang X, Cho SY, Nimmagadda S, Pomper MG. Prostate-specific membrane antigen as a target for cancer imaging and therapy. THE QUARTERLY JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING : OFFICIAL PUBLICATION OF THE ITALIAN ASSOCIATION OF NUCLEAR MEDICINE (AIMN) [AND] THE INTERNATIONAL ASSOCIATION OF RADIOPHARMACOLOGY (IAR), [AND] SECTION OF THE SOCIETY OF... 2015; 59:241-68. [PMID: 26213140 PMCID: PMC4859214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 11/12/2023]
Abstract
The prostate-specific membrane antigen (PSMA) is a molecular target whose use has resulted in some of the most productive work toward imaging and treating prostate cancer over the past two decades. A wide variety of imaging agents extending from intact antibodies to low-molecular-weight compounds permeate the literature. In parallel there is a rapidly expanding pool of antibody-drug conjugates, radiopharmaceutical therapeutics, small-molecule drug conjugates, theranostics and nanomedicines targeting PSMA. Such productivity is motivated by the abundant expression of PSMA on the surface of prostate cancer cells and within the neovasculature of other solid tumors, with limited expression in most normal tissues. Animating the field is a variety of small-molecule scaffolds upon which the radionuclides, drugs, MR-detectable species and nanoparticles can be placed with relative ease. Among those, the urea-based agents have been most extensively leveraged, with expanding clinical use for detection and more recently for radiopharmaceutical therapy of prostate cancer, with surprisingly little toxicity. PSMA imaging of other cancers is also appearing in the clinical literature, and may overtake FDG for certain indications. Targeting PSMA may provide a viable alternative or first-line approach to managing prostate and other cancers.
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Affiliation(s)
- A P Kiess
- Department of Radiation Oncology, Johns Hopkins Medical Institutions, Baltimore, MD, USA -
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