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Kaihani S, Sadeghzadeh N, Abediankenari S, Abedi SM. [ 99mTc]-labeling and evaluation of a new linear peptide for imaging of glioblastoma as a α vβ 3-positive tumor. Ann Nucl Med 2022; 36:976-985. [PMID: 36097232 DOI: 10.1007/s12149-022-01786-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 08/23/2022] [Indexed: 01/05/2023]
Abstract
PURPOSE In this study, we designed a new linear 6-Hydrazinonicotinamide (HYNIC)-conjugated peptide (HYNIC-KRWrNM) (M-6) and labeled with technetium-99m for gamma imaging of glioblastoma as a αvβ3-positive tumor. We evaluated tumor targeting ability of this radio-peptide and compared with previous 99mTc-labeled HYNIC-conjugated RGD analogue peptides. PROCEDURES One new linear peptide (HYNIC-KRWrNM) (M-6) was designed and labeled with technetium-99m in the presence of 2-[[1,3-dihydroxy-2-(hydroxymethyl) propan-2-yl] amino] acetic acid (Tricine)/Ethylenediamine-N,N'-diacetic acid (EDDA) as co-ligand system. Then, this 99mTc-labeled peptide ([99mTc]Tc-M-7) was evaluated for in vitro stability in saline and serum, specific binding assay, internalization, and binding affinity (Kd). In addition, we performed biodistribution study and planar imaging on nude mice bearing U87-MG xenograft as a αvβ3-positive tumor. RESULTS The radiochemical yield of [99mTc]Tc-M-7 was obtained ˃95%. This 99mTc-labeled peptide remained stable and intact in saline solution after 24 h incubation. In addition, metabolic stability of this 99mTc-labeled peptide was obtained ˃60% after 4 h incubation in serum. The Kd value for [99mTc]Tc-M-7 was obtained 5.2 ± 1.0 nM. Based on biodistribution results in nude mice bearing U87-MG xenograft, tumor/muscle activity ratio was 6.22 and decreased to 1.89 in blocking group at the same time point (4 h p.i.). The blocking experiment results also indicated that tumor uptake and kidney uptake were αvβ3-mediated. In comparison with previous HYNIC-conjugated RGD analogue peptides, kidneys had the highest uptake of this 99mTc-labeled peptide (52.29 ± 11.48 at 1.5 h p.i. and 27.04 ± 0.66%ID/g at 4 h p.i.). Finally, similar to previous 99mTc-labeled HYNIC-conjugated RGD analogue peptides, [99mTc]Tc-M-7 showed acceptable tumor uptake after 4 h post-injection (based on ROI technique, target-to-background activity ratio = 3.80). CONCLUSIONS This small linear 99mTc-labeled peptide, with high affinity to αvβ3 integrin, desirable water solubility, and cost efficient, demonstrates a potent tumor targeting ability as well as previous HYNIC-conjugated RGD analogue peptides. Hence, [99mTc]Tc-M-7 can be of service to as a new candidate for early detection of αvβ3-positive tumors.
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Affiliation(s)
- Sajad Kaihani
- Department of Radiopharmacy, Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, 48471-93698, Mazandaran, Iran.,Student Research Committee, Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, Iran
| | - Nourollah Sadeghzadeh
- Department of Radiopharmacy, Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, 48471-93698, Mazandaran, Iran.
| | - Saeid Abediankenari
- Immunogenetics Research Centre, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Seyed Mohammad Abedi
- Department of Radiology, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
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Advances in Development of Radiometal Labeled Amino Acid-Based Compounds for Cancer Imaging and Diagnostics. Pharmaceuticals (Basel) 2021; 14:ph14020167. [PMID: 33669938 PMCID: PMC7924883 DOI: 10.3390/ph14020167] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 02/13/2021] [Accepted: 02/18/2021] [Indexed: 02/08/2023] Open
Abstract
Radiolabeled biomolecules targeted at tumor-specific enzymes, receptors, and transporters in cancer cells represent an intensively investigated and promising class of molecular tools for the cancer diagnosis and therapy. High specificity of such biomolecules is a prerequisite for the treatment with a lower burden to normal cells and for the effective and targeted imaging and diagnosis. Undoubtedly, early detection is a key factor in efficient dealing with many severe tumor types. This review provides an overview and critical evaluation of novel approaches in the designing of target-specific probes labeled with metal radionuclides for the diagnosis of most common death-causing cancers, published mainly within the last three years. Advances are discussed such traditional peptide radiolabeling approaches, and click and nanoparticle chemistry. The progress of radiolabeled peptide based ligands as potential radiopharmaceuticals is illustrated via novel structure and application studies, showing how the molecular modifications reflect their binding selectivity to significant onco-receptors, toxicity, and, by that, practical utilization. The most impressive outputs in categories of newly developed structures, as well as imaging and diagnosis approaches, and the most intensively studied oncological diseases in this context, are emphasized in order to show future perspectives of radiometal labeled amino acid-based compounds in nuclear medicine.
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Christou N, Blondy S, David V, Verdier M, Lalloué F, Jauberteau MO, Mathonnet M, Perraud A. Neurotensin pathway in digestive cancers and clinical applications: an overview. Cell Death Dis 2020; 11:1027. [PMID: 33268796 PMCID: PMC7710720 DOI: 10.1038/s41419-020-03245-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 11/01/2020] [Accepted: 11/02/2020] [Indexed: 02/06/2023]
Abstract
Initially, NEUROTENSIN (NTS) has been shown to play physiological and biological functions as a neuro-transmitter/modulator in the central nervous system and as an endocrine factor in the periphery, through its binding to two kinds of receptors: NTSR1 and 2 (G protein-coupled receptors) and NTSR3/sortilin (a vacuolar protein-sorting 10-domain receptor). NTS also plays oncogenic roles in many types of cancer, including digestive cancers. In tumor tissues, NTS and NTSR1 expression is higher than in healthy ones and is associated with poor prognosis. NTS and NTRS1 promote cancer progression and play key functions in metastatic processes; they modulate several signaling pathways and they contribute to changes in the tumor microenvironment. Conversely, NTRS2 involvement in digestive cancers is poorly understood. Discovered for mediating NTS biological effects, sortilin recently emerged as a promising target as its expression was found to be increased in various types of cancers. Because it can be secreted, a soluble form of sortilin (sSortilin) appears as a new serum biomarker which, on the basis of recent studies, promises to be useful in both the diagnosis and tumor progression monitoring. More precisely, it appears that soluble sortilin can be associated with other receptors like TRKB. These associations occur in exosomes and trigger the aggressiveness of cancers like glioblastoma, leading to the concept of a possible composite theranostic biomarker. This review summarizes the oncogenic roles of the NTS signaling pathways in digestive cancers and discusses their emergence as promising early diagnostic and/or prognostic biomarkers and therapeutic targets.
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Affiliation(s)
- Niki Christou
- Laboratoire EA3842 CAPTuR « Contrôle de l'Activation cellulaire, Progression Tumorale et Résistances thérapeutiques », Faculté de médecine, 2 rue du Docteur Marcland, 87025, Limoges, France.
- Service de Chirurgie Digestive, Endocrinienne et Générale, CHU de Limoges, 2 avenue Martin Luther King, 87042, Limoges, France.
| | - Sabrina Blondy
- Laboratoire EA3842 CAPTuR « Contrôle de l'Activation cellulaire, Progression Tumorale et Résistances thérapeutiques », Faculté de médecine, 2 rue du Docteur Marcland, 87025, Limoges, France
| | - Valentin David
- Laboratoire EA3842 CAPTuR « Contrôle de l'Activation cellulaire, Progression Tumorale et Résistances thérapeutiques », Faculté de médecine, 2 rue du Docteur Marcland, 87025, Limoges, France
- Service de Pharmacie, CHU de Limoges, 2 avenue Martin Luther King, 87042, Limoges, France
| | - Mireille Verdier
- Laboratoire EA3842 CAPTuR « Contrôle de l'Activation cellulaire, Progression Tumorale et Résistances thérapeutiques », Faculté de médecine, 2 rue du Docteur Marcland, 87025, Limoges, France
| | - Fabrice Lalloué
- Laboratoire EA3842 CAPTuR « Contrôle de l'Activation cellulaire, Progression Tumorale et Résistances thérapeutiques », Faculté de médecine, 2 rue du Docteur Marcland, 87025, Limoges, France
| | - Marie-Odile Jauberteau
- Laboratoire EA3842 CAPTuR « Contrôle de l'Activation cellulaire, Progression Tumorale et Résistances thérapeutiques », Faculté de médecine, 2 rue du Docteur Marcland, 87025, Limoges, France
- Service d'Immunologie, CHU de Limoges, 2 avenue Martin Luther King, 87042, Limoges, France
| | - Muriel Mathonnet
- Laboratoire EA3842 CAPTuR « Contrôle de l'Activation cellulaire, Progression Tumorale et Résistances thérapeutiques », Faculté de médecine, 2 rue du Docteur Marcland, 87025, Limoges, France
- Service de Chirurgie Digestive, Endocrinienne et Générale, CHU de Limoges, 2 avenue Martin Luther King, 87042, Limoges, France
| | - Aurélie Perraud
- Laboratoire EA3842 CAPTuR « Contrôle de l'Activation cellulaire, Progression Tumorale et Résistances thérapeutiques », Faculté de médecine, 2 rue du Docteur Marcland, 87025, Limoges, France
- Service de Chirurgie Digestive, Endocrinienne et Générale, CHU de Limoges, 2 avenue Martin Luther King, 87042, Limoges, France
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Maleki F, Masteri Farahani A, Sadeghzadeh N, Mardanshahi A, Abediankenari S. Preparation and evaluation of
99m
Tc‐HYNIC‐
D
(TPPE) as a new targeted imaging probe for detection of colon cancer: Preclinical comparison with
99m
Tc‐HYNIC‐EPPT. Chem Biol Drug Des 2020; 96:1223-1231. [DOI: 10.1111/cbdd.13707] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 05/05/2020] [Accepted: 05/10/2020] [Indexed: 12/18/2022]
Affiliation(s)
- Fariba Maleki
- Faculty of Pharmacy Department of Radiopharmacy Mazandaran University of Medical Sciences Sari Iran
- Student Research Committee Mazandaran University of Medical Sciences Sari Iran
| | - Arezou Masteri Farahani
- Faculty of Pharmacy Department of Radiopharmacy Mazandaran University of Medical Sciences Sari Iran
- Student Research Committee Mazandaran University of Medical Sciences Sari Iran
| | - Nourollah Sadeghzadeh
- Faculty of Pharmacy Department of Radiopharmacy Mazandaran University of Medical Sciences Sari Iran
| | - Alireza Mardanshahi
- Department of Radiology Faculty of Medicine Mazandaran University of Medical Sciences Sari Iran
| | - Saeid Abediankenari
- Immunogenetics Research Center Mazandaran University of Medical Sciences Sari Iran
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Farahani AM, Maleki F, Sadeghzadeh N, Abediankenari S, Abedi SM, Erfani M. Evaluation of a New <sup>99m</sup>Tc-labeled GnRH Analogue as a Possible Imaging Agent for Prostate Cancer Detection. Anticancer Agents Med Chem 2020; 20:1695-1703. [PMID: 32560611 DOI: 10.2174/1871520620666200619175352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 03/09/2020] [Accepted: 04/13/2020] [Indexed: 11/22/2022]
Abstract
INTRODUCTION Prostate cancer is a serious threat to men's health so it is necessary to develop technics for early detection of this malignancy. The purpose of this research was the evaluation of a new99mTc-labeled GnRH analogue as an imaging probe for tumor targeting of prostate cancer. METHODS 99mTc-labeled-DLys6-GnRH analogue was prepared based on HYNIC as a chelating agent and tricine/ EDDA as coligands for labeling with 99mTc. HYNIC was coupled to epsilon amino group of DLys6 through aminobutyric acid (GABA) as a linker. Radiochemical purity and stability in normal saline and serum, were determined by TLC and HPLC methods. Furthermore, calculation of protein-binding and partition coefficient constant were carried out for 99mTc labeled peptide. The cellular experiments including receptor binding specificity and affinity were studied using three prostate cancer cell lines LN-CaP, DU-145 and PC-3. Finally, the animal assessment and SPECT imaging of radiolabeled GnRH analogue were evaluated on normal mice and nude mice bearing LN-CaP tumor. RESULTS The GnRH conjugate was labeled with high radiochemical purity (~97%). The radiolabeled peptide showed efficient stability in the presence of normal saline and human serum. The in vitro cellular assays on three prostate cancer cell lines indicated that the radiotracer was bound to LN-CaP cells with higher affinity compared to DU-145 and PC-3 cells. The Kd values of 99mTc- HYNIC (tricine/ EDDA)-Gaba-D-Lys6GnRH were 89.39±26.71, 93.57±30.49 and107.3±18.82 in LN-CaP, PC-3 and DU-145 cells respectively. The biodistribution studies in normal mice and LN-CaP tumor-bearing nude mice showed similar results including rapid blood clearance and low radioactivity accumulation in non-target organs. High kidney uptake proved that the main excretion route of radiopeptide was through the urinary system. The tumor uptake was 1.72±0.45 %ID/g at 1h p.i. decreasing to 0.70±0.06%ID/g at 4h p.i. for 99mTc-HYNIC-Gaba-D-Lys6GnRH. The maximum tumor/ muscle ratio was 2.30 at 1h p.i. Pre-saturation of receptor using an excess of unlabeled peptide revealed that the tumor uptake was receptor mediated. The results of the SPECT image of LN-CaP tumor were in agreement with the biodistribution data. CONCLUSION Based on this study, we suggest LN-CaP as a favorable cell line for in vivo studies on GnRH analogues. Moreover, this report shows that 99mTc-HYNIC (tricine/EDDA)-Gaba-D-Lys6GnRH may be a suitable candidate for further evaluation of prostate cancer.
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Affiliation(s)
- Arezou Masteri Farahani
- Department of Radiopharmacy, Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, Iran,Student Research Committee, Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, Iran
| | - Fariba Maleki
- Department of Radiopharmacy, Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, Iran,Student Research Committee, Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, Iran
| | - Nourollah Sadeghzadeh
- Department of Radiopharmacy, Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, Iran
| | - Saeid Abediankenari
- Immunogenetics Research Centre, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Seyed Mohammad Abedi
- Department of Radiology, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Mostafa Erfani
- Radiation Application Research School, Nuclear Science and Technology Research Institute (NSTRI), Tehran, Iran
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Masteri Farahani A, Maleki F, Sadeghzadeh N, Abediankenari S, Abedi SM, Erfani M. 99m Tc-(EDDA/tricine)-HYNIC-GnRH analogue as a potential imaging probe for diagnosis of prostate cancer. Chem Biol Drug Des 2020; 96:850-860. [PMID: 32279449 DOI: 10.1111/cbdd.13693] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 03/20/2020] [Accepted: 03/26/2020] [Indexed: 12/16/2022]
Abstract
Prostate cancer is a serious threat to men's health, so it is necessary to develop the techniques for early detection of this malignancy. Radiolabeled peptides are the useful tools for diagnosis of prostate cancer. In this research, we designed a new HYNIC-conjugated GnRH analogue and labeled it by 99m Tc with tricine/EDDA as coligands. We used aminohexanoic acid (Ahx) as a hydrocarbon linker to generate 99m Tc-(tricine/EDDA)-HYNIC-Ahx-[DLys6 ]GnRH. The radiopeptide exhibited high radiochemical purity and stability in solution and serum. Two human prostate cancer cell lines LN-CaP and DU-145 were used for cellular experiments. The binding specificity and affinity of radiopeptide for LN-CaP were superior to DU-145 cells. The Kd values for LN-CaP and DU-145 cells were 41.91 ± 7.03 nM and 55.96 ± 10.56 nM, respectively. High kidney uptake proved that the main excretion route of radiopeptide was through the urinary system. The tumor/muscle ratio of 99m Tc-HYNIC-Ahx-[DLys6 ]GnRH was 4.14 at 1 hr p.i. that decreased to 2.41 at 4 hr p.i. in LN-CaP tumor-xenografted nude mice. The blocking experiment revealed that the tumor uptake was receptor-mediated. The lesion was visualized clearly using 99m Tc-[DLys6 ]GnRH at 1 hr p.i. Accordingly, this research highlights the capability of 99m Tc-(tricine/EDDA)-HYNIC-Ahx-[DLys6 ]GnRH peptide as a promising agent for GnRHR-expressing tumor imaging.
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Affiliation(s)
- Arezou Masteri Farahani
- Department of Radiopharmacy, Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, Iran.,Student Research Committee, Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, Iran
| | - Fariba Maleki
- Department of Radiopharmacy, Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, Iran.,Student Research Committee, Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, Iran
| | - Nourollah Sadeghzadeh
- Department of Radiopharmacy, Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, Iran
| | - Saeid Abediankenari
- Immunogenetics Research Centre, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Seyed Mohammad Abedi
- Department of Radiology, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - Mostafa Erfani
- Radiation Application Research School, Nuclear Science and Technology Research Institute (NSTRI), Tehran, Iran
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Franco Machado J, Silva RD, Melo R, G Correia JD. Less Exploited GPCRs in Precision Medicine: Targets for Molecular Imaging and Theranostics. Molecules 2018; 24:E49. [PMID: 30583594 PMCID: PMC6337414 DOI: 10.3390/molecules24010049] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Revised: 12/07/2018] [Accepted: 12/09/2018] [Indexed: 12/18/2022] Open
Abstract
Precision medicine relies on individually tailored therapeutic intervention taking into account individual variability. It is strongly dependent on the availability of target-specific drugs and/or imaging agents that recognize molecular targets and patient-specific disease mechanisms. The most sensitive molecular imaging modalities, Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET), rely on the interaction between an imaging radioprobe and a target. Moreover, the use of target-specific molecular tools for both diagnostics and therapy, theranostic agents, represent an established methodology in nuclear medicine that is assuming an increasingly important role in precision medicine. The design of innovative imaging and/or theranostic agents is key for further accomplishments in the field. G-protein-coupled receptors (GPCRs), apart from being highly relevant drug targets, have also been largely exploited as molecular targets for non-invasive imaging and/or systemic radiotherapy of various diseases. Herein, we will discuss recent efforts towards the development of innovative imaging and/or theranostic agents targeting selected emergent GPCRs, namely the Frizzled receptor (FZD), Ghrelin receptor (GHSR-1a), G protein-coupled estrogen receptor (GPER), and Sphingosine-1-phosphate receptor (S1PR). The pharmacological and clinical relevance will be highlighted, giving particular attention to the studies on the synthesis and characterization of targeted molecular imaging agents, biological evaluation, and potential clinical applications in oncology and non-oncology diseases. Whenever relevant, supporting computational studies will be also discussed.
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Affiliation(s)
- João Franco Machado
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, CTN, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal.
- Centro de Química Estrutural, Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal.
| | - Rúben D Silva
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, CTN, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal.
| | - Rita Melo
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, CTN, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal.
- Center for Neuroscience and Cell Biology; Rua Larga, Faculdade de Medicina, Polo I, 1ºandar, Universidade de Coimbra, 3004-504 Coimbra, Portugal.
| | - João D G Correia
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, CTN, Estrada Nacional 10 (km 139,7), 2695-066 Bobadela LRS, Portugal.
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Rezazadeh F, Sadeghzadeh N, Abedi SM, Abediankenari S. 99mTc labeled D(LPR): A novel retro-inverso peptide for VEGF receptor-1 targeted tumor imaging. Nucl Med Biol 2018; 62-63:54-62. [PMID: 29885559 DOI: 10.1016/j.nucmedbio.2018.05.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Revised: 05/25/2018] [Accepted: 05/25/2018] [Indexed: 12/01/2022]
Abstract
INTRODUCTION The aim of this study was to evaluate the ability of D(LPR), a novel retro-inverso peptidomimetic derivative for imaging colon cancer. METHODS Two different D(LPR) analogs were designed and compared based on conjugation of HYNIC at peptide's C or N terminal and then labeled with technetium-99m using tricine/EDDA as an exchange coligands. The radiolabeled conjugates were assessed for in vitro stability in saline and serum. The VEGFR-1 and NRP-1 receptors affinity, in vitro internalization and also dissociation Constance was evaluated. SPCET imaging and biodistribution studies were performed in nude mice bearing HT-29 xenograft tumors. RESULTS Both peptides labeled with technetium-99m in high radiochemical yield (˃97%). Peptide stability studies indicated a high metabolic stability of the radiopeptides in solution and serum. In vitro blocking studies demonstrated specific binding and internalization of [99mTc]Tc-HYNIC-peptides in cultured HUVEC cells. The Kd value for 99mTc-peptide 1 and 99mTc-peptide 2 were found to be 56.8 ± 12.9 nM and 71.6 ± 17.9 nM respectively. The tumor to muscle ratio was significant at 0.5 and 1 h after injection (4.5 and 4 for 99mTc-peptide 1 and 4.9 and 4.4 for 99mTc-peptide 2 at 0.5 and 1 h p.i. respectively). SPECT imaging studies revealed that both radioconjugates had prominent activity accumulation in VEGFR-1 and NRP-1 expressing HT-29 tumors. CONCLUSION This study is the first instance of using a radiolabeled retro-inverso peptide for tumor imaging which is a promising tool to improve the performance of fragile peptide probes in vivo as imaging agents and warrant further investigations in other peptide-target systems.
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Affiliation(s)
- Farzaneh Rezazadeh
- Faculty of Pharmacy, Department of Radiopharmacy, Mazandaran University of Medical Sciences, Sari, Iran; Student Research Committee, Mazandaran University of Medical Sciences, Sari, Iran
| | - Nourollah Sadeghzadeh
- Faculty of Pharmacy, Department of Radiopharmacy, Mazandaran University of Medical Sciences, Sari, Iran.
| | - Seyed Mohammad Abedi
- Faculty of Medicine, Department of Radiology, Mazandaran University of Medical Sciences, Sari, Iran
| | - Saeid Abediankenari
- Immunogenetics Research Center, Mazandaran University of Medical Sciences, Sari, Iran
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