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Vyas D, Patel M, Wairkar S. Strategies for active tumor targeting-an update. Eur J Pharmacol 2022; 915:174512. [PMID: 34555395 DOI: 10.1016/j.ejphar.2021.174512] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 09/03/2021] [Accepted: 09/17/2021] [Indexed: 01/26/2023]
Abstract
A complete cure for cancer is still the holy grail for scientists. The existing treatment of cancer is primarily focused on surgery, radiation and conventional chemotherapy. However, chemotherapeutic agents also affect healthy tissues or organs due to a lack of specificity. While passive targeting is studied for anticancer drugs focused on the enhanced permeability and retention effect, it failed to achieve drug accumulation at the tumor site and desired therapeutic efficacy. This review presents an outline of the current significant targets for active tumor drug delivery systems and provides insight into the direction of active tumor-targeting strategies. For this purpose, a systematic understanding of the physiological factors, tumor microenvironment and its components, overexpressed receptor and associated proteins are covered here. We focused on angiogenesis mediated targeting, receptor-mediated targeting and peptide targeting. This active targeting along with integration with nano delivery systems helps in achieving specific action, thus reducing the associated adverse effects to healthy tissues. Although the tumor-targeting methods and possibilities explored so far seem revolutionary in cancer treatment, in-depth clinical studies data is required for its commercial translation.
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Affiliation(s)
- Darshan Vyas
- Shobhaben Pratapbhai Patel School of Pharmacy & Technology Management, SVKMs NMIMS, V.L.Mehta Road, Vile Parle (W), Mumbai, Maharashtra, 400056, India
| | - Mital Patel
- Shobhaben Pratapbhai Patel School of Pharmacy & Technology Management, SVKMs NMIMS, V.L.Mehta Road, Vile Parle (W), Mumbai, Maharashtra, 400056, India
| | - Sarika Wairkar
- Shobhaben Pratapbhai Patel School of Pharmacy & Technology Management, SVKMs NMIMS, V.L.Mehta Road, Vile Parle (W), Mumbai, Maharashtra, 400056, India.
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Kang S, Lee S, Park S. iRGD Peptide as a Tumor-Penetrating Enhancer for Tumor-Targeted Drug Delivery. Polymers (Basel) 2020; 12:E1906. [PMID: 32847045 PMCID: PMC7563641 DOI: 10.3390/polym12091906] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 08/20/2020] [Accepted: 08/21/2020] [Indexed: 02/06/2023] Open
Abstract
The unique structure and physiology of a tumor microenvironment impede intra-tumoral penetration of chemotherapeutic agents. A novel iRGD peptide that exploits the tumor microenvironment can activate integrin-dependent binding to tumor vasculatures and neuropilin-1 (NRP-1)-dependent transport to tumor tissues. Recent studies have focused on its dual-targeting ability to achieve enhanced penetration of chemotherapeutics for the efficient eradication of cancer cells. Both the covalent conjugation and the co-administration of iRGD with chemotherapeutic agents and engineered delivery vehicles have been explored. Interestingly, the iRGD-mediated drug delivery also enhances penetration through the blood-brain barrier (BBB). Recent studies have shown its synergistic effect with BBB disruptive techniques. The efficacy of immunotherapy involving immune checkpoint blockades has also been amplified by using iRGD as a targeting moiety. In this review, we presented the recent advances in iRGD technology, focusing on cancer treatment modalities, including the current clinical trials using iRGD. The iRGD-mediated nano-carrier system could serve as a promising strategy in drug delivery to the deeper tumor regions, and be combined with various therapeutic interventions due to its novel targeting ability.
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Affiliation(s)
| | | | - Soyeun Park
- College of Pharmacy, Keimyung University, 1095 Dalgubeoldaero, Dalseo-gu, Daegu 42601, Korea; (S.K.); (S.L.)
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Tee JK, Yip LX, Tan ES, Santitewagun S, Prasath A, Ke PC, Ho HK, Leong DT. Nanoparticles' interactions with vasculature in diseases. Chem Soc Rev 2019; 48:5381-5407. [PMID: 31495856 DOI: 10.1039/c9cs00309f] [Citation(s) in RCA: 187] [Impact Index Per Article: 37.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The ever-growing use of inorganic nanoparticles (NPs) in biomedicine provides an exciting approach to develop novel imaging and drug delivery systems, owing to the ease with which these NPs can be functionalized to cater to various applications. In cancer therapeutics, nanomedicine generally relies on the enhanced permeability and retention (EPR) effect observed in tumour vasculature to deliver anti-cancer drugs across the endothelium. However, such a phenomenon is dependent on the tumour microenvironment and is not consistently observed in all tumour types, thereby limiting drug transport to the tumour site. On the other hand, there is a rise in utilizing inorganic NPs to intentionally induce endothelial leakiness, creating a window of opportunity to control drug delivery across the endothelium. While this active targeting approach creates a similar phenomenon compared to the EPR effect arising from tumour tissues, its drug delivery applications extend beyond cancer therapeutics and into other vascular-related diseases. In this review, we summarize the current findings of the EPR effect and assess its limitations in the context of anti-cancer drug delivery systems. While the EPR effect offers a possible route for drug passage, we further explore alternative uses of NPs to create controllable endothelial leakiness within short exposures, a phenomenon we coined as nanomaterial-induced endothelial leakiness (NanoEL). Furthermore, we discuss the main mechanistic features of the NanoEL effect that make it unique from conventionally established endothelial leakiness in homeostatic and pathologic conditions, as well as examine its potential applicability in vascular-related diseases, particularly cancer. Therefore, this new paradigm changes the way inorganic NPs are currently being used for biomedical applications.
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Affiliation(s)
- Jie Kai Tee
- Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore 117585, Singapore.
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Cui J, Yue JB. Current status and advances in arginine‐glycine‐aspartic acid peptide‐based molecular imaging to evaluate the effects of anti‐angiogenic therapies. PRECISION RADIATION ONCOLOGY 2019. [DOI: 10.1002/pro6.60] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Affiliation(s)
- Jin Cui
- Taishan Medical University Taian Shandong China
| | - Jin Bo Yue
- Shandong Cancer Hospital Jinan Shandong China
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Azcona PL, Montiel Schneider MG, Grünhut M, Lassalle VL. Stimuli-responsive nanotheranostics intended for oncological diseases: in vitro evaluation of their target, diagnostic and drug release capabilities. NEW J CHEM 2019. [DOI: 10.1039/c8nj05289a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This work reports an overview of required in vitro assays to evaluate nanotheranostics applications.
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Affiliation(s)
- Pamela Liliana Azcona
- INQUISUR
- Departamento de Química
- Universidad Nacional del Sur (UNS)-CONICET
- 8000 Bahía Blanca
- Argentina
| | | | - Marcos Grünhut
- INQUISUR
- Departamento de Química
- Universidad Nacional del Sur (UNS)-CONICET
- 8000 Bahía Blanca
- Argentina
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Qiao Y, Wan J, Zhou L, Ma W, Yang Y, Luo W, Yu Z, Wang H. Stimuli‐responsive nanotherapeutics for precision drug delivery and cancer therapy. WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2018; 11:e1527. [DOI: 10.1002/wnan.1527] [Citation(s) in RCA: 170] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 03/16/2018] [Accepted: 03/23/2018] [Indexed: 02/06/2023]
Affiliation(s)
- Yiting Qiao
- The First Affiliated Hospital; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases; Key Laboratory of Combined Multi‐Organ Transplantation, Ministry of Public Health, School of Medicine Zhejiang University Hangzhou P.R. China
| | - Jianqin Wan
- The First Affiliated Hospital; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases; Key Laboratory of Combined Multi‐Organ Transplantation, Ministry of Public Health, School of Medicine Zhejiang University Hangzhou P.R. China
- Department of Chemical Engineering Zhejiang University Hangzhou P.R. China
| | - Liqian Zhou
- The First Affiliated Hospital; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases; Key Laboratory of Combined Multi‐Organ Transplantation, Ministry of Public Health, School of Medicine Zhejiang University Hangzhou P.R. China
| | - Wen Ma
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of New Drug Screening Southern Medical University Guangzhou P.R. China
| | - Yuanyuan Yang
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of New Drug Screening Southern Medical University Guangzhou P.R. China
| | - Weixuan Luo
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of New Drug Screening Southern Medical University Guangzhou P.R. China
| | - Zhiqiang Yu
- School of Pharmaceutical Sciences, Guangdong Provincial Key Laboratory of New Drug Screening Southern Medical University Guangzhou P.R. China
| | - Hangxiang Wang
- The First Affiliated Hospital; Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases; Key Laboratory of Combined Multi‐Organ Transplantation, Ministry of Public Health, School of Medicine Zhejiang University Hangzhou P.R. China
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Kumar K, Ghosh A. 18F-AlF Labeled Peptide and Protein Conjugates as Positron Emission Tomography Imaging Pharmaceuticals. Bioconjug Chem 2018; 29:953-975. [PMID: 29463084 DOI: 10.1021/acs.bioconjchem.7b00817] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The clinical applications of positron emission tomography (PET) imaging pharmaceuticals have increased tremendously over the past several years since the approval of 18fluorine-fluorodeoxyglucose (18F-FDG) by the Food and Drug Administration (FDA). Numerous 18F-labeled target-specific potential imaging pharmaceuticals, based on small and large molecules, have been evaluated in preclinical and clinical settings. 18F-labeling of organic moieties involves the introduction of the radioisotope by C-18F bond formation via a nucleophilic or an electrophilic substitution reaction. However, biomolecules, such as peptides, proteins, and oligonucleotides, cannot be radiolabeled via a C-18F bond formation as these reactions involve harsh conditions, including organic solvents, high temperature, and nonphysiological conditions. Several approaches, including 18F-labeled prosthetic groups, silicon, boron, and aluminum fluoride acceptor chemistry, and click chemistry have been developed, in the past, for 18F labeling of biomolecules. Linear and macrocyclic polyaminocarboxylates and their analogs and derivatives form thermodynamically stable and kinetically inert aluminum chelates. Hence, macrocyclic polyaminocarboxylates have been used for conjugation with biomolecules, such as folate, peptides, affibodies, and protein fragments, followed by 18F-AlF chelation, and evaluation of their targeting abilities in preclinical and clinical environments. The goal of this report is to provide an overview of the 18F radiochemistry and 18F-labeling methodologies for small molecules and target-specific biomolecules, a comprehensive review of coordination chemistry of Al3+, 18F-AlF labeling of peptide and protein conjugates, and evaluation of 18F-labeled biomolecule conjugates as potential imaging pharmaceuticals.
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Affiliation(s)
- Krishan Kumar
- Laboratory for Translational Research in Imaging Pharmaceuticals, The Wright Center of Innovation in Biomedical Imaging, Department of Radiology , The Ohio State University , Columbus , Ohio 43212 , United States
| | - Arijit Ghosh
- Laboratory for Translational Research in Imaging Pharmaceuticals, The Wright Center of Innovation in Biomedical Imaging, Department of Radiology , The Ohio State University , Columbus , Ohio 43212 , United States
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Potential of α7 nicotinic acetylcholine receptor PET imaging in atherosclerosis. Methods 2017; 130:90-104. [PMID: 28602809 DOI: 10.1016/j.ymeth.2017.06.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 06/02/2017] [Accepted: 06/06/2017] [Indexed: 02/07/2023] Open
Abstract
Atherosclerotic events are usually acute and often strike otherwise asymptomatic patients. Although multiple clinical risk factors have been associated with atherosclerosis, as of yet no further individual prediction can be made as to who will suffer from its consequences based on biomarker analysis or traditional imaging methods like CT, MRI or angiography. Previously, non-invasive imaging with 18F-fluorodeoxyglucose (18F-FDG) PET was shown to potentially fill this niche as it offers high sensitive detection of metabolic processes associated with inflammatory changes in atherosclerotic plaques. However, 18F-FDG PET imaging of arterial vessels suffers from non-specificity and has still to be proven to reliably identify vulnerable plaques, carrying a high risk of rupture. Therefore, it may be regarded only as a secondary marker for monitoring treatment effects and it does not offer alternative treatment options or direct insight in treatment mechanisms. In this review, an overview is given of the current status and the potential of PET imaging of inflammation and angiogenesis in atherosclerosis in general and special emphasis is given to imaging of α7 nicotinic acetylcholine receptors (α7 nAChRs). Due to the gaps that still exist in our understanding of atherogenesis and the limitations of the available PET tracers, the search continues for a more specific radioligand, able to differentiate between stable atherosclerosis and plaques prone to rupture. The potential role of the α7 nAChR as imaging marker for plaque vulnerability is explored. Today, strong evidence exists that nAChRs are involved in the atherosclerotic disease process. They are suggested to mediate the deleterious effects of the major tobacco component, nicotine, a nAChR agonist. Mainly based on in vitro data, α7 nAChR stimulation might increase plaque burden via increased neovascularization. However, in animal studies, α7 nAChR manipulation appears to reduce plaque size due to its inhibitory effects on inflammatory cells. Thus, reliable identification of α7 nAChRs by in vivo imaging is crucial to investigate the exact role of α7 nAChR in atherosclerosis before any therapeutic approach in the human setting can be justified. In this review, we discuss the first experience with α7 nAChR PET tracers and developmental considerations regarding the "optimal" PET tracer to image vascular nAChRs.
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Xu D, Zhao ZQ, Chen ST, Yang Y, Fang W, Liu S. Iminodiacetic acid as bifunctional linker for dimerization of cyclic RGD peptides. Nucl Med Biol 2017; 48:1-8. [DOI: 10.1016/j.nucmedbio.2017.01.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 01/03/2017] [Accepted: 01/17/2017] [Indexed: 12/18/2022]
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Shi J, Wang F, Liu S. Radiolabeled cyclic RGD peptides as radiotracers for tumor imaging. BIOPHYSICS REPORTS 2016; 2:1-20. [PMID: 27819026 PMCID: PMC5071373 DOI: 10.1007/s41048-016-0021-8] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 03/01/2016] [Indexed: 12/19/2022] Open
Abstract
The integrin family comprises 24 transmembrane receptors, each a heterodimeric combination of one of 18α and one of 8β subunits. Their main function is to integrate the cell adhesion and interaction with the extracellular microenvironment with the intracellular signaling and cytoskeletal rearrangement through transmitting signals across the cell membrane upon ligand binding. Integrin αvβ3 is a receptor for the extracellular matrix proteins containing arginine–glycine–aspartic (RGD) tripeptide sequence. The αvβ3 is generally expressed in low levels on the epithelial cells and mature endothelial cells, but it is highly expressed in many solid tumors. The αvβ3 levels correlate well with the potential for tumor metastasis and aggressiveness, which make it an important biological target for development of antiangiogenic drugs, and molecular imaging probes for early tumor diagnosis. Over the last decade, many radiolabeled cyclic RGD peptides have been evaluated as radiotracers for imaging tumors by SPECT or PET. Even though they are called “αvβ3-targeted” radiotracers, the radiolabeled cyclic RGD peptides are also able to bind αvβ5, α5β1, α6β4, α4β1, and αvβ6 integrins, which may help enhance their tumor uptake due to the “increased receptor population.” This article will use the multimeric cyclic RGD peptides as examples to illustrate basic principles for development of integrin-targeted radiotracers and focus on different approaches to maximize their tumor uptake and T/B ratios. It will also discuss important assays for pre-clinical evaluations of the integrin-targeted radiotracers, and their potential applications as molecular imaging tools for noninvasive monitoring of tumor metastasis and early detection of the tumor response to antiangiogenic therapy.
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Affiliation(s)
- Jiyun Shi
- Interdisciplinary Laboratory, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101 China ; Medical Isotopes Research Center, Peking University, Beijing, 100191 China
| | - Fan Wang
- Interdisciplinary Laboratory, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101 China ; Medical Isotopes Research Center, Peking University, Beijing, 100191 China
| | - Shuang Liu
- School of Health Sciences, Purdue University, West Lafayette, IN 47907 USA
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Comparison of biological properties of 99mTc-labeled cyclic RGD Peptide trimer and dimer useful as SPECT radiotracers for tumor imaging. Nucl Med Biol 2016; 43:661-669. [PMID: 27556955 DOI: 10.1016/j.nucmedbio.2016.02.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 02/12/2016] [Accepted: 02/22/2016] [Indexed: 11/22/2022]
Abstract
INTRODUCTION This study sought to evaluate a 99mTc-labeled trimeric cyclic RGD peptide (99mTc-4P-RGD3) as the new radiotracer for tumor imaging. The objective was to compare its biological properties with those of 99mTc-3P-RGD2 in the same animal model. METHODS HYNIC-4P-RGD3 was prepared by reacting 4P-RGD3 with excess HYNIC-OSu in the presence of diisopropylethylamine. 99mTc-4P-RGD3 was prepared using a kit formulation, and evaluated for its tumor-targeting capability and biodistribution properties in the BALB/c nude mice with U87MG human glioma xenografts. Planar and SPECT imaging studies were performed in athymic nude mice with U87MG glioma xenografts. For comparison purpose, 99mTc-3P-RGD2 (a αvβ3-targeted radiotracer currently under clinical evaluation for tumor imaging in cancer patients) was also evaluated in the same animal models. Blocking experiments were used to demonstrate the αvβ3 specificity of 99mTc-4P-RGD3. RESULTS 99mTc-4P-RGD3 was prepared with >95% RCP and high specific activity (~200GBq/μmol). 99mTc-4P-RGD3 and 99mTc-3P-RGD2 shared almost identical tumor uptake and similar biodistribution properties. 99mTc-4P-RGD3 had higher uptake than 99mTc-3P-RGD2 in the intestines and kidneys; but it showed better metabolic stability. The U87MG tumors were clearly visualized by SPECT with excellent contrast with 99mTc-4P-RGD3 and 99mTc-3P-RGD2. CONCLUSION Increasing peptide multiplicity from 3P-RGD2 to 4P-RGD3 offers no advantages with respect to the tumor-targeting capability. 99mTc-4P-RGD3 is as good a SPECT radiotracer as 99mTc-3P-RGD2 for imaging αvβ3-positive tumors.
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Liu S. Radiolabeled Cyclic RGD Peptide Bioconjugates as Radiotracers Targeting Multiple Integrins. Bioconjug Chem 2015; 26:1413-38. [PMID: 26193072 DOI: 10.1021/acs.bioconjchem.5b00327] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Angiogenesis is a requirement for tumor growth and metastasis. The angiogenic process depends on vascular endothelial cell migration and invasion, and is regulated by various cell adhesion receptors. Integrins are such a family of receptors that facilitate the cellular adhesion to and migration on extracellular matrix proteins in the intercellular spaces and basement membranes. Among 24 members of the integrin family, αvβ3 is studied most extensively for its role in tumor angiogenesis and metastasis. The αvβ3 is expressed at relatively low levels on epithelial cells and mature endothelial cells, but it is highly expressed on the activated endothelial cells of tumor neovasculature and some tumor cells. This restricted expression makes αvβ3 an excellent target to develop antiangiogenic drugs and diagnostic molecular imaging probes. Since αvβ3 is a receptor for extracellular matrix proteins with one or more RGD tripeptide sequence, many radiolabeled cyclic RGD peptides have been evaluated as "αvβ3-targeted" radiotracers for tumor imaging over the past decade. This article will use the dimeric and tetrameric cyclic RGD peptides developed in our laboratories as examples to illustrate basic principles for development of αvβ3-targeted radiotracers. It will focus on different approaches to maximize the radiotracer tumor uptake and tumor/background ratios. This article will also discuss some important assays for preclinical evaluations of integrin-targeted radiotracers. In general, multimerization of cyclic RGD peptides increases their integrin binding affinity and the tumor uptake and retention times of their radiotracers. Regardless of their multiplicity, the capability of cyclic RGD peptides to bind other integrins (namely, αvβ5, α5β1, α6β4, α4β1, and αvβ6) is expected to enhance the radiotracer tumor uptake due to the increased integrin population. The results from preclinical and clinical studies clearly show that radiolabeled cyclic RGD peptides (such as (99m)Tc-3P-RGD2, (18)F-Alfatide-I, and (18)F-Alfatide-II) are useful as the molecular imaging probes for early cancer detection and noninvasive monitoring of the tumor response to antiangiogenic therapy.
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Affiliation(s)
- Shuang Liu
- School of Health Sciences, Purdue University, 550 Stadium Mall Drive, West Lafayette, Indiana 47907, United States
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Hassan M, Selimovic D, El-Khattouti A, Soell M, Ghozlan H, Haikel Y, Abdelkader O, Megahed M. Hepatitis C virus-mediated angiogenesis: Molecular mechanisms and therapeutic strategies. World J Gastroenterol 2014; 20:15467-15475. [PMID: 25400432 PMCID: PMC4229513 DOI: 10.3748/wjg.v20.i42.15467] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Accepted: 05/19/2014] [Indexed: 02/06/2023] Open
Abstract
Angiogenesis is an essential process for organ growth and repair. Thus, an imbalance in this process can lead to several diseases including malignancy. Angiogenesis is a critical step in vascular remodeling, tissue damage and wound healing besides being required for invasive tumor growth and metastasis. Because angiogenesis sets an important point in the control of tumor progression, its inhibition is considered a valuable therapeutic approach for tumor treatment. Chronic liver disease including hepatitis C virus (HCV) infection is one of the main cause for the development of hepatic angiogenesis and thereby plays a critical role in the modulation of hepatic angiogenesis that finally leads to hepatocellular carcinoma progression and invasion. Thus, understanding of the molecular mechanisms of HCV-mediated hepatic angiogenesis will help design a therapeutic protocol for the intervention of HCV-mediated angiogenesis and subsequently its outcome. In this review, we will focus on the molecular mechanisms of HCV-mediated hepatic angiogenesis and the related signaling pathways that can be target for current and under development therapeutic approaches.
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Biodistribution and imaging of [99mTc]-HYNIC-RGD in MDA-MB-231 and NTERA-2 cancer cell xenografts. Nucl Med Commun 2013; 34:709-17. [DOI: 10.1097/mnm.0b013e328361f552] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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16
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Siraj A, Desestret V, Antoine M, Fromont G, Huerre M, Sanson M, Camparo P, Pichon C, Planeix F, Gonin J, Radu A, Ghinea N. Expression of follicle-stimulating hormone receptor by the vascular endothelium in tumor metastases. BMC Cancer 2013; 13:246. [PMID: 23688201 PMCID: PMC3663659 DOI: 10.1186/1471-2407-13-246] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Accepted: 05/16/2013] [Indexed: 11/26/2022] Open
Abstract
Background The Follicle Stimulating Hormone receptor (FSHR) is expressed by the vascular endothelium in a wide range of human tumors. It was not determined however if FSHR is present in metastases which are responsible for the terminal illness. Methods We used immunohistochemistry based on a highly FSHR-specific monoclonal antibody to detect FSHR in cancer metastases from 6 major tumor types (lung, breast, prostate, colon, kidney, and leiomyosarcoma ) to 6 frequent locations (bone, liver, lymph node, brain, lung, and pleura) of 209 patients. Results In 166 patients examined (79%), FSHR was expressed by blood vessels associated with metastatic tissue. FSHR-positive vessels were present in the interior of the tumors and some few millimeters outside, in the normally appearing tissue. In the interior of the metastases, the density of the FSHR-positive vessels was constant up to 7 mm, the maximum depth available in the analyzed sections. No significant differences were noticed between the density of FSHR-positive vessels inside vs. outside tumors for metastases from lung, breast, colon, and kidney cancers. In contrast, for prostate cancer metastases, the density of FSHR-positive vessels was about 3-fold higher at the exterior of the tumor compared to the interior. Among brain metastases, the density of FSHR-positive vessels was highest in lung and kidney cancer, and lowest in prostate and colon cancer. In metastases of breast cancer to the lung pleura, the percentage of blood vessels expressing FSHR was positively correlated with the progesterone receptor level, but not with either HER-2 or estrogen receptors. In normal tissues corresponding to the host organs for the analyzed metastases, obtained from patients not known to have cancer, FSHR staining was absent, with the exception of approx. 1% of the vessels in non tumoral temporal lobe epilepsy samples. Conclusion FSHR is expressed by the endothelium of blood vessels in the majority of metastatic tumors.
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Affiliation(s)
- Ahsan Siraj
- Inserm Equipe Angiogenèse Tumorale, Institut Curie, Centre de Recherche, Département Recherche Translationnelle, 26 rue d'Ulm, 75005, Paris, France
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Cai H, Conti PS. RGD-based PET tracers for imaging receptor integrin αv β3 expression. J Labelled Comp Radiopharm 2013; 56:264-79. [PMID: 24285371 DOI: 10.1002/jlcr.2999] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Revised: 11/02/2012] [Accepted: 11/06/2012] [Indexed: 12/20/2022]
Abstract
Positron emission tomography (PET) imaging of receptor integrin αv β3 expression may play a key role in the early detection of cancer and cardiovascular diseases, monitoring disease progression, evaluating therapeutic response, and aiding anti-angiogenic drugs discovery and development. The last decade has seen the development of new PET tracers for in vivo imaging of integrin αv β3 expression along with advances in PET chemistry. In this review, we will focus on the radiochemistry development of PET tracers based on arginine-glycine-aspartic acid (RGD) peptide, present an overview of general strategies for preparing RGD-based PET tracers, and review the recent advances in preparations of (18) F-labeled, (64) Cu-labeled, and (68) Ga-labeled RGD tracers, RGD-based PET multivalent probes, and RGD-based PET multimodality probes for imaging receptor integrin αv β3 expression.
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Affiliation(s)
- Hancheng Cai
- PET Center, Children's Hospital of Michigan, Detroit Medical Center, Detroit, MI, 48201, USA; Wayne State University School of Medicine, Detroit, MI, 48201, USA
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Jo JI, Lin X, Nakahara T, Aoki I, Saga T, Tabata Y. Preparation of Polymer-Based Magnetic Resonance Imaging Contrast Agent to Visualize Therapeutic Angiogenesis. Tissue Eng Part A 2013; 19:30-9. [DOI: 10.1089/ten.tea.2012.0131] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Affiliation(s)
- Jun-ichiro Jo
- Department of Biomaterials, Institute for Frontier Medical Sciences, Kyoto University, Kyoto, Japan
- Diagnostic Imaging Program, Molecular Imaging Center, National Institute of Radiological Sciences, Chiba, Japan
| | - Xue Lin
- Department of Biomaterials, Institute for Frontier Medical Sciences, Kyoto University, Kyoto, Japan
| | - Teppei Nakahara
- Diagnostic Imaging Program, Molecular Imaging Center, National Institute of Radiological Sciences, Chiba, Japan
| | - Ichio Aoki
- Diagnostic Imaging Program, Molecular Imaging Center, National Institute of Radiological Sciences, Chiba, Japan
| | - Tsuneo Saga
- Diagnostic Imaging Program, Molecular Imaging Center, National Institute of Radiological Sciences, Chiba, Japan
| | - Yasuhiko Tabata
- Department of Biomaterials, Institute for Frontier Medical Sciences, Kyoto University, Kyoto, Japan
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In search of active RGD peptides: Theoretical study of hydrogen bonding in five-member ring cyclic-RGD isomers. COMPUT THEOR CHEM 2012. [DOI: 10.1016/j.comptc.2012.07.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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20
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Ashrafi SA, Hosseinimehr SJ, Varmira K, Abedi SM. Radioimmunotherapy with ¹³¹I-bevacizumab as a specific molecule for cells with overexpression of the vascular endothelial growth factor. Cancer Biother Radiopharm 2012; 27:420-5. [PMID: 22690909 DOI: 10.1089/cbr.2012.1224] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Bevacizumab is a humanized monoclonal antibody that inhibits vascular endothelial growth factor A and is used for the treatment of several cancers. We labeled this monoclonal antibody with Iodine-131 (¹³¹I) and performed in vitro quality control and tumor cell growth inhibition tests. Bevacizumab was labeled with ¹³¹I using chloramine T. Radiochemical purity and stability in phosphate-buffered saline and human blood serum were determined using thin-layer chromatography and radio-sodium dodecyl sulfate-polyacrylamide gel electrophoresis, respectively, performed at different times. Cell-specific binding, internalization, and toxicity of the radiolabeled antibody were tested using the SKOV-3 ovarian cancer cell line. The biodistribution of ¹³¹I-bevacizumab was investigated using male mice. The radiochemical purity of the complex was 99% ± 0.7%. Its stability in phosphate-buffered saline and human blood serum at 48 hours postpreparation was 78% ± 1.2% and 93% ± 0.6%, respectively. (131)I-bevacizumab was significantly bound to SKOV-3. The internalization of ¹³¹I-bevacizumab was time dependent, and it was cleared from the blood after 24 hours. Significant reductions in SKOV-3 cell viability were achieved with (131)I-bevacizumab at a concentration of 500 nM. A low accumulation of ¹³¹I-bevacizumab was observed in the stomach and salivary glands after 24 hours and 48 hours. These findings indicate that the new radiolabeled antibody should be further evaluated in animals and, possibly, in humans as a new radiopharmaceutical agent for use in radioimmunotherapy for ovarian cancer.
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Affiliation(s)
- Saeb Ahmad Ashrafi
- Department of Radiopharmacy, Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari, Iran
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21
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Taylor RM, Severns V, Brown DC, Bisoffi M, Sillerud LO. Prostate cancer targeting motifs: expression of αν β3, neurotensin receptor 1, prostate specific membrane antigen, and prostate stem cell antigen in human prostate cancer cell lines and xenografts. Prostate 2012; 72:523-32. [PMID: 21748756 PMCID: PMC4366051 DOI: 10.1002/pros.21454] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2011] [Accepted: 06/15/2011] [Indexed: 12/28/2022]
Abstract
BACKGROUND Membrane receptors are frequent targets of cancer therapeutic and imaging agents. However, promising in vitro results often do not translate to in vivo clinical applications. To better understand this obstacle, we measured the expression differences in receptor signatures among several human prostate cancer cell lines and xenografts as a function of tumorigenicity. METHODS Messenger RNA and protein expression levels for integrin α(ν) β(3), neurotensin receptor 1 (NTSR1), prostate specific membrane antigen (PSMA), and prostate stem cell antigen (PSCA) were measured in LNCaP, C4-2, and PC-3 human prostate cancer cell lines and in murine xenografts using quantitative reverse transcriptase polymerase chain reaction, flow cytometry, and immunohistochemistry. RESULTS Stable expression patterns were observed for integrin α(ν) and PSMA in all cells and corresponding xenografts. Integrin β(3) mRNA expression was greatly reduced in C4-2 xenografts and greatly elevated in PC-3 xenografts compared with the corresponding cultured cells. NTSR1 mRNA expression was greatly elevated in LNCaP and PC-3 xenografts. PSCA mRNA expression was elevated in C4-2 xenografts when compared with C4-2 cells cultured in vitro. Furthermore, at the protein level, PSCA was re-expressed in all xenografts compared with cells in culture. CONCLUSIONS The regulation of mRNA and protein expression of the cell-surface target proteins α(ν) β(3), NTSR1, PSMA, and PSCA, in prostate cancer cells with different tumorigenic potential, was influenced by factors of the microenvironment, differing between cell cultures and murine xenotransplants. Integrin α(ν) β(3), NTRS1 and PSCA mRNA expression increased with tumorigenic potential, but mRNA expression levels for these proteins do not translate directly to equivalent expression levels of membrane bound protein.
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Affiliation(s)
- Robert M Taylor
- Department of Biochemistry and Molecular Biology, University of New Mexico School of Medicine, Albuquerque, NM 87131, USA.
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22
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Liu Y, Pressly ED, Abendschein DR, Hawker CJ, Woodard GE, Woodard PK, Welch MJ. Targeting angiogenesis using a C-type atrial natriuretic factor-conjugated nanoprobe and PET. J Nucl Med 2011; 52:1956-63. [PMID: 22049461 PMCID: PMC4255943 DOI: 10.2967/jnumed.111.089581] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED Sensitive, specific, and noninvasive detection of angiogenesis would be helpful in discovering new strategies for the treatment of cardiovascular diseases. Recently, we reported the (64)Cu-labeled C-type atrial natriuretic factor (CANF) fragment for detecting the upregulation of natriuretic peptide clearance receptor (NPR-C) with PET on atherosclerosis-like lesions in an animal model. However, it is unknown whether NPR-C is present and overexpressed during angiogenesis. The goal of this study was to develop a novel CANF-integrated nanoprobe to prove the presence of NPR-C and offer sensitive detection with PET during development of angiogenesis in mouse hind limb. METHODS We prepared a multifunctional, core-shell nanoparticle consisting of DOTA chelators attached to a poly(methyl methacrylate) core and CANF-targeting moieties attached to poly(ethylene glycol) chain ends in the shell of the nanoparticle. Labeling of this nanoparticle with (64)Cu yielded a high-specific-activity nanoprobe for PET imaging NPR-C receptor in a mouse model of hind limb ischemia-induced angiogenesis. Histology and immunohistochemistry were performed to assess angiogenesis development and NPR-C localization. RESULTS (15)O-H(2)O imaging showed blood flow restoration in the previously ischemic hind limb, consistent with the development of angiogenesis. The targeted DOTA-CANF-comb nanoprobe showed optimized pharmacokinetics and biodistribution. PET imaging demonstrated significantly higher tracer accumulation for the targeted DOTA-CANF-comb nanoprobe than for either the CANF peptide tracer or the nontargeted control nanoprobe (P < 0.05, both). Immunohistochemistry confirmed NPR-C upregulation in the angiogenic lesion with colocalization in both endothelial and smooth muscle cells. PET and immunohistochemistry competitive receptor blocking verified the specificity of the targeted nanoprobe to NPR-C receptor. CONCLUSION As evidence of its translational potential, this customized DOTA-CANF-comb nanoprobe demonstrated superiority over the CANF peptide alone for imaging NPR-C receptor in angiogenesis.
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Affiliation(s)
- Yongjian Liu
- Department of Radiology, Washington University, St. Louis, Missouri
| | - Eric D. Pressly
- Department of Materials, Chemistry, and Biochemistry, University of California, Santa Barbara, California
| | | | - Craig J. Hawker
- Department of Materials, Chemistry, and Biochemistry, University of California, Santa Barbara, California
| | - Geoffrey E. Woodard
- Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | | | - Michael J. Welch
- Department of Radiology, Washington University, St. Louis, Missouri
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Belotti D, Foglieni C, Resovi A, Giavazzi R, Taraboletti G. Targeting angiogenesis with compounds from the extracellular matrix. Int J Biochem Cell Biol 2011; 43:1674-85. [DOI: 10.1016/j.biocel.2011.08.012] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Revised: 08/05/2011] [Accepted: 08/10/2011] [Indexed: 02/08/2023]
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Affiliation(s)
- Ruth Duncan
- Polymer Therapeutics Lab., Centro de Investigación Príncipe Felipe, Av. Autopista del Saler 16 E-46012, Valencia, Spain
| | - Rogerio Gaspar
- Nanomedicine & Drug Delivery Systems Group, iMed, Faculty of Pharmacy of the University of Lisbon, Av. Prof Gama Pinto, 1649-003 Lisbon, Portugal
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Wängler C, Maschauer S, Prante O, Schäfer M, Schirrmacher R, Bartenstein P, Eisenhut M, Wängler B. Multimerization of cRGD peptides by click chemistry: synthetic strategies, chemical limitations, and influence on biological properties. Chembiochem 2011; 11:2168-81. [PMID: 20827791 DOI: 10.1002/cbic.201000386] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Integrin α(ν)β(3) is overexpressed on endothelial cells of growing vessels as well as on several tumor types, and so integrin-binding radiolabeled cyclic RGD pentapeptides have attracted increasing interest for in vivo imaging of α(ν)β(3) integrin expression by positron emission tomography (PET). Of the cRGD derivatives available for imaging applications, systems comprising multiple cRGD moieties have recently been shown to exhibit highly favorable properties in relation to monomers. To assess the synthetic limits of the cRGD-multimerization approach and thus the maximum multimer size achievable by using different efficient conjugation reactions, we prepared a variety of multimers that were further investigated in vitro with regard to their avidities to integrin α(ν)β(3.) The synthesized peptide multimers containing increasing numbers of cRGD moieties on PAMAM dendrimer scaffolds were prepared by different click chemistry coupling strategies. A cRGD hexadecimer was the largest construct that could be synthesized under optimized reaction conditions, thus identifying the current synthetic limitations for cRGD multimerization. The obtained multimeric systems were conjugated to a new DOTA-based chelator developed for the derivatization of sterically demanding structures and successfully labeled with (68)Ga for a potential in vivo application. The evaluated multimers showed very high avidities-increasing with the number of cRGD moieties-in in vitro studies on immobilized α(ν)β(3) integrin and U87MG cells, of up to 131- and 124-fold, respectively, relative to the underivatized monomer.
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Affiliation(s)
- Carmen Wängler
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, H3A 2B4 QC, Canada.
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Synthesis and evaluation of new iRGD peptide analogs for tumor optical imaging. Bioorg Med Chem Lett 2010; 21:1146-50. [PMID: 21251820 DOI: 10.1016/j.bmcl.2010.12.112] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2010] [Revised: 12/18/2010] [Accepted: 12/21/2010] [Indexed: 01/02/2023]
Abstract
Recently, a disulfide-based cyclic RGD peptide called iRGD, that is, c(CRGDKGPDC), has been reported to interact with both integrin and neuropilin-1 receptors for cellular and deep tissue penetration to improve the imaging sensitivity and therapeutic efficacy. In this study, two new near-infrared fluorescent iRGD conjugates, that is, Ac-Cys(IRDye®800CW)-iRGD (1), and its dual labeling analog DOTA-Cys(IRDye®800CW)-iRGD (2) were synthesized via the specific mercapto-maleimide reaction for tumor imaging. Both 1 and 2 showed significant tumor localization in optical imaging of MDA-MB-435 tumor-bearing mice. The potential of such iRGD compounds in tumor-targeted imaging and drug delivery deserves further exploration.
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Danhier F, Feron O, Préat V. To exploit the tumor microenvironment: Passive and active tumor targeting of nanocarriers for anti-cancer drug delivery. J Control Release 2010; 148:135-46. [PMID: 20797419 DOI: 10.1016/j.jconrel.2010.08.027] [Citation(s) in RCA: 1723] [Impact Index Per Article: 123.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2010] [Accepted: 08/10/2010] [Indexed: 12/12/2022]
Abstract
Because of the particular characteristics of the tumor microenvironment and tumor angiogenesis, it is possible to design drug delivery systems that specifically target anti-cancer drugs to tumors. Most of the conventional chemotherapeutic agents have poor pharmacokinetics profiles and are distributed non-specifically in the body leading to systemic toxicity associated with serious side effects. Therefore, the development of drug delivery systems able to target the tumor site is becoming a real challenge that is currently addressed. Nanomedicine can reach tumor passively through the leaky vasculature surrounding the tumors by the Enhanced Permeability and Retention effect whereas ligands grafted at the surface of nanocarriers allow active targeting by binding to the receptors overexpressed by cancer cells or angiogenic endothelial cells. This review is divided into two parts: the first one describes the tumor microenvironment and the second one focuses on the exploitation and the understanding of these characteristics to design new drug delivery systems targeting the tumor. Delivery of conventional chemotherapeutic anti-cancer drugs is mainly discussed.
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Affiliation(s)
- Fabienne Danhier
- Université Catholique de Louvain, Louvain Drug Research Institute, Unit of Pharmaceutics, UCL-FARG 7320, Avenue E. Mounier, B-1200, Brussels, Belgium
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Deshpande N, Pysz MA, Willmann JK. Molecular ultrasound assessment of tumor angiogenesis. Angiogenesis 2010; 13:175-88. [PMID: 20549555 DOI: 10.1007/s10456-010-9175-z] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2010] [Accepted: 06/03/2010] [Indexed: 12/11/2022]
Abstract
Angiogenesis, the growth of new blood vessels, plays a critical role in progression of tumor growth and metastasis, making it an attractive target for both cancer imaging and therapy. Several molecular markers, including those that are involved in the angiogenesis signaling pathway and those unique to tumor angiogenic vessels, have been identified and can be used as targets for molecular imaging of cancer. With the introduction of ultrasound contrast agents that can be targeted to those molecular markers, targeted contrast-enhanced ultrasound (molecular ultrasound) imaging has become an attractive imaging modality to non-invasively assess tumor angiogenesis at the molecular level. The advantages of molecular ultrasound imaging such as high temporal and spatial resolution, non-invasiveness, real-time imaging, relatively low cost, lack of ionizing irradiation and wide availability among the imaging community will further expand its roles in cancer imaging and drug development both in preclinical research and future clinical applications.
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Affiliation(s)
- Nirupama Deshpande
- Department of Radiology, Molecular Imaging Program at Stanford, Stanford University School of Medicine, 300 Pasteur Drive, Room H1307, Stanford, CA, USA
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Dickinson RE, Duncan WC. The SLIT-ROBO pathway: a regulator of cell function with implications for the reproductive system. Reproduction 2010; 139:697-704. [PMID: 20100881 PMCID: PMC2971463 DOI: 10.1530/rep-10-0017] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The secreted SLIT glycoproteins and their Roundabout (ROBO) receptors were originally identified as important axon guidance molecules. They function as a repulsive cue with an evolutionarily conserved role in preventing axons from migrating to inappropriate locations during the assembly of the nervous system. In addition the SLIT-ROBO interaction is involved in the regulation of cell migration, cell death and angiogenesis and, as such, has a pivotal role during the development of other tissues such as the lung, kidney, liver and breast. The cellular functions that the SLIT/ROBO pathway controls during tissue morphogenesis are processes that are dysregulated during cancer development. Therefore inactivation of certain SLITs and ROBOs is associated with advanced tumour formation and progression in disparate tissues. Recent research has indicated that the SLIT/ROBO pathway could also have important functions in the reproductive system. The fetal ovary expresses most members of the SLIT and ROBO families. The SLITs and ROBOs also appear to be regulated by steroid hormones and regulate physiological cell functions in adult reproductive tissues such as the ovary and endometrium. Furthermore several SLITs and ROBOs are aberrantly expressed during the development of ovarian, endometrial, cervical and prostate cancer. This review will examine the roles this pathway could have in the development, physiology and pathology of the reproductive system and highlight areas for future research that could further dissect the influence of the SLIT/ROBO pathway in reproduction.
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Affiliation(s)
- Rachel E Dickinson
- MRC Human Reproductive Sciences Unit Division of Reproductive and Developmental Sciences, The Queen's Medical Research Institute, Centre for Reproductive Biology, The University of Edinburgh, Edinburgh EH16 4TJ, Scotland, UK.
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Abstract
The various types of cells that comprise the tumor mass all carry molecular markers that are not expressed or are expressed at much lower levels in normal cells. These differentially expressed molecules can be used as docking sites to concentrate drug conjugates and nanoparticles at tumors. Specific markers in tumor vessels are particularly well suited for targeting because molecules at the surface of blood vessels are readily accessible to circulating compounds. The increased concentration of a drug in the site of disease made possible by targeted delivery can be used to increase efficacy, reduce side effects, or achieve some of both. We review the recent advances in this delivery approach with a focus on the use of molecular markers of tumor vasculature as the primary target and nanoparticles as the delivery vehicle.
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Affiliation(s)
- Erkki Ruoslahti
- Vascular Mapping Center, Sanford-Burnham Medical Research Institute, University of California, Santa Barbara, Santa Barbara, CA 93106, USA.
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Current and future aspects of molecular imaging. Methods 2009; 48:81-2. [DOI: 10.1016/j.ymeth.2009.05.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2009] [Accepted: 05/22/2009] [Indexed: 11/20/2022] Open
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