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Venu A, Zhang Y, Seong J, Hong Y, Lee WS, Min JJ. Engineering of an EPHA2-Targeted Monobody for the Detection of Colorectal Cancer. Cancer Genomics Proteomics 2024; 21:285-294. [PMID: 38670584 PMCID: PMC11059598 DOI: 10.21873/cgp.20447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 01/26/2024] [Accepted: 02/20/2024] [Indexed: 04/28/2024] Open
Abstract
BACKGROUND/AIM Colorectal cancer (CRC) is the third most common cancer worldwide, and is second only to lung cancer with respect to cancer-related deaths. Noninvasive molecular imaging using established markers is a new emerging method to diagnose CRC. The human ephrin receptor family type-A 2 (hEPHA2) oncoprotein is overexpressed at the early, but not late, stages of CRC. Previously, we reported development of an E1 monobody that is specific for hEPHA2-expressing cancer cells both in vitro and in vivo. Herein, we investigated the ability of the E1 monobody to detect hEPHA2 expressing colorectal tumors in a mouse model, as well as in CRC tissue. MATERIALS AND METHODS The expression of hEPHA2 on the surface of CRC cells was analyzed by western blotting and flow cytometry. The targeting efficacy of the E1 monobody for CRC cells was examined by flow cytometry, and immunofluorescence staining. E1 conjugated to the Renilla luciferase variant 8 (Rluc8) reporter protein was used for in vivo imaging in mice. Additionally, an enhanced green fluorescence protein (EGFP) conjugated E1 monobody was used to check the ability of the E1 monobody to target CRC tissue. RESULTS The E1 monobody bound efficiently to hEPHA2-expressing CRC cell lines, and E1 conjugated to the Rluc8 reporter protein targeted tumor tissues in mice transplanted with HCT116 CRC tumor cells. Finally, E1-EGFP stained tumor tissues from human CRC patients, showing a pattern similar to that of an anti-hEPHA2 antibody. CONCLUSION The E1 monobody has utility as an EPHA2 targeting agent for the detection of CRC.
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Affiliation(s)
- Akhil Venu
- Department of Nuclear Medicine, Institute for Molecular Imaging and Theranostics, Hwasun Hospital, Chonnam National University Medical School, Hwasun, Republic of Korea
- Department of Biomedical Sciences, Chonnam National University Medical School, Jeonnam, Republic of Korea
| | - Ying Zhang
- Department of Nuclear Medicine, Institute for Molecular Imaging and Theranostics, Hwasun Hospital, Chonnam National University Medical School, Hwasun, Republic of Korea
| | - Jihyoun Seong
- Division of Gastroenterology, Department of Internal Medicine, Chonnam National University Medical School and Hospital, Gwangju, Republic of Korea
| | - Yeongjin Hong
- Department of Microbiology, Chonnam National University Medical School, Hwasun, Republic of Korea
| | - Wan-Sik Lee
- Division of Gastroenterology, Department of Internal Medicine, Chonnam National University Medical School and Hospital, Gwangju, Republic of Korea;
| | - Jung-Joon Min
- Department of Nuclear Medicine, Institute for Molecular Imaging and Theranostics, Hwasun Hospital, Chonnam National University Medical School, Hwasun, Republic of Korea;
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Goncalves BG, Banerjee IA. A computational and laboratory approach for the investigation of interactions of peptide conjugated natural terpenes with EpHA2 receptor. J Mol Model 2023; 29:204. [PMID: 37291458 DOI: 10.1007/s00894-023-05596-3] [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: 07/06/2022] [Accepted: 05/17/2023] [Indexed: 06/10/2023]
Abstract
CONTEXT Ephrin type A receptor 2 (EphA2) is a well-known drug target for cancer treatment due to its overexpression in numerous types of cancers. Thus, it is crucial to determine the binding interactions of this receptor with both the ligand-binding domain (LBD) and the kinase-binding domain (KBD) through a targeted approach in order to modulate its activity. In this work, natural terpenes with inherent anticancer properties were conjugated with short peptides YSAYP and SWLAY that are known to bind to the LBD of EphA2 receptor. We examined the binding interactions of six terpenes (maslinic acid, levopimaric acid, quinopimaric acid, oleanolic, polyalthic, and hydroxybetulinic acid) conjugated to the above peptides with the ligand-binding domain (LBD) of EphA2 receptor computationally. Additionally, following the "target-hopping approach," we also examined the interactions of the conjugates with the KBD. Our results indicated that most of the conjugates showed higher binding interactions with the EphA2 kinase domain compared to LBD. Furthermore, the binding affinities of the terpenes increased upon conjugating the peptides with the terpenes. In order to further investigate the specificity toward EphA2 kinase domain, we also examined the binding interactions of the terpenes conjugated to VPWXE (x = norleucine), as VPWXE has been shown to bind to other RTKs. Our results indicated that the terpenes conjugated to SWLAY in particular showed high efficacy toward binding to the KBD. We also designed conjugates where in the peptide portion and the terpenes were separated by a butyl (C4) group linker to examine if the binding interactions could be enhanced. Docking studies showed that the conjugates with linkers had enhanced binding with the LBD compared to those without linkers, though binding remained slightly higher without linkers toward the KBD. As a proof of concept, maslinate and oleanolate conjugates of each of the peptides were then tested with F98 tumor cells which are known to overexpress EphA2 receptor. Results indicated that the oleanolate-amido-SWLAY conjugates were efficacious in reducing the cell proliferation of the tumor cells and may be potentially developed and further studied for targeting tumor cells overexpressing the EphA2 receptor. To test if these conjugates could bind to the receptor and potentially function as kinase inhibitors, we conducted SPR analysis and ADP-Glo assay. Our results indicated that OA conjugate with SWLAY showed the highest inhibition. METHODS Docking studies were carried out using AutoDock Vina, v.1.2.0; Molecular Dynamics and MMGBSA calculations were carried out through Schrodinger Software DESMOND.
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Affiliation(s)
- Beatriz G Goncalves
- Department of Chemistry, Fordham University, 441 East Fordham Road, Bronx, NY, 10458, USA
| | - Ipsita A Banerjee
- Department of Chemistry, Fordham University, 441 East Fordham Road, Bronx, NY, 10458, USA.
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Baggio C, Udompholkul P, Gambini L, Pellecchia M. Targefrin: A Potent Agent Targeting the Ligand Binding Domain of EphA2. J Med Chem 2022; 65:15443-15456. [PMID: 36331527 PMCID: PMC9706575 DOI: 10.1021/acs.jmedchem.2c01391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Indexed: 11/06/2022]
Abstract
Overexpression of the receptor tyrosine kinase EphA2 is invariably associated with poor prognosis and development of aggressive metastatic cancers. Guided by our recently solved X-ray structure of the complex between an agonistic peptide and EphA2-LBD, we report on a novel agent, targefrin, that binds to EphA2-LBD with a 21 nM dissociation constant by isothermal titration calorimetry and presents an IC50 value of 10.8 nM in a biochemical assay. In cell-based assays, a dimeric version of the agent is as effective as the natural dimeric ligands (ephrinA1-Fc) in inducing cellular receptor internalization and degradation in several pancreatic cancer cell lines. When conjugated with chemotherapy, the agents can effectively deliver paclitaxel to pancreatic cancers in a mouse xenograft study. Given the pivotal role of EphA2 in tumor progression, we are confident that the agents reported could be further developed into innovative EphA2-targeting therapeutics.
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Affiliation(s)
| | | | - Luca Gambini
- Division of Biomedical Sciences,
School of Medicine, University of California
Riverside, 900 University
Avenue, Riverside, California 92521, United States
| | - Maurizio Pellecchia
- Division of Biomedical Sciences,
School of Medicine, University of California
Riverside, 900 University
Avenue, Riverside, California 92521, United States
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4
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Hunting for Novel Routes in Anticancer Drug Discovery: Peptides against Sam-Sam Interactions. Int J Mol Sci 2022; 23:ijms231810397. [PMID: 36142306 PMCID: PMC9499636 DOI: 10.3390/ijms231810397] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 09/02/2022] [Accepted: 09/02/2022] [Indexed: 01/10/2023] Open
Abstract
Among the diverse protein binding modules, Sam (Sterile alpha motif) domains attract attention due to their versatility. They are present in different organisms and play many functions in physiological and pathological processes by binding multiple partners. The EphA2 receptor contains a Sam domain at the C-terminus (EphA2-Sam) that is able to engage protein regulators of receptor stability (including the lipid phosphatase Ship2 and the adaptor Odin). Ship2 and Odin are recruited by EphA2-Sam through heterotypic Sam-Sam interactions. Ship2 decreases EphA2 endocytosis and consequent degradation, producing chiefly pro-oncogenic outcomes in a cellular milieu. Odin, through its Sam domains, contributes to receptor stability by possibly interfering with ubiquitination. As EphA2 is upregulated in many types of tumors, peptide inhibitors of Sam-Sam interactions by hindering receptor stability could function as anticancer therapeutics. This review describes EphA2-Sam and its interactome from a structural and functional perspective. The diverse design strategies that have thus far been employed to obtain peptides targeting EphA2-mediated Sam-Sam interactions are summarized as well. The generated peptides represent good initial lead compounds, but surely many efforts need to be devoted in the close future to improve interaction affinities towards Sam domains and consequently validate their anticancer properties.
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Wu T, Jiang J, Wang H, He Y, Zhao X, Xue Y, Xu H. Design, synthesis, and in vivo evaluation of GO-SWL-Ahx-K-SWL. Bioorg Med Chem Lett 2022; 70:128802. [PMID: 35598792 DOI: 10.1016/j.bmcl.2022.128802] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 05/12/2022] [Accepted: 05/16/2022] [Indexed: 12/24/2022]
Abstract
In order to acquire both expanded binding ability with the EphA2 receptor and superior drug delivery capacity, we designed and synthesized the modified GO-SWL-Ahx-K-SWL conjugate as a potential targeted therapeutic drug for non-small cell lung cancer (NSCLC). Various characterization methods have confirmed that the conjugate is consistent with the theoretical peptide. The cytotoxicity test results showed that the conjugate was slightly more toxic to A549 cells than in 3 T3 cells, and the toxicity increased in a concentration-dependent manner. Single photon emission computed tomography/computed tomography (SPECT/CT) fusion imaging was performed to evaluate the conjugate binding to EphA2 receptor in vivo. The images showed obvious radioactive concentration in tumor tissues and significantly higher ratios of the tumor and muscle in the 125I-GO-SWL-Ahx-K-SWL group (10.78) than in the 125I-SWL-Ahx-K-SWL group (5.21) at all three time points (P < 0.01).
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Affiliation(s)
- Tao Wu
- Department of Nuclear Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, China
| | - Jinhui Jiang
- Department of Nuclear Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, China
| | - Hui Wang
- Department of Nuclear Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, China
| | - Yanhui He
- Department of Nuclear Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, China
| | - Xuefeng Zhao
- Department of Nuclear Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, China
| | - Yangyang Xue
- Department of Nuclear Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, China
| | - Huiqin Xu
- Department of Nuclear Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei 230022, China.
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Qu B, Han Y, Liang T, Zhang C, Hou G, Gao F. Evaluation of a novel EphA2 targeting peptide for triple negative breast cancer based on radionuclide molecular imaging. ARAB J CHEM 2022. [DOI: 10.1016/j.arabjc.2022.104211] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
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Udompholkul P, Baggio C, Gambini L, Sun Y, Zhao M, Hoffman RM, Pellecchia M. Effective Tumor Targeting by EphA2-Agonist-Biotin-Streptavidin Conjugates. Molecules 2021; 26:3687. [PMID: 34204178 PMCID: PMC8235110 DOI: 10.3390/molecules26123687] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2021] [Revised: 06/04/2021] [Accepted: 06/07/2021] [Indexed: 11/22/2022] Open
Abstract
We recently reported on a potent synthetic agent, 135H11, that selectively targets the receptor tyrosine kinase, EphA2. While 135H11 possesses a relatively high binding affinity for the ligand-binding domain of EphA2 (Kd~130 nM), receptor activation in the cell required the synthesis of dimeric versions of such agent (namely 135H12). This was expected given that the natural ephrin ligands also need to be dimerized or clustered to elicit agonistic activity in cell. In the present report we investigated whether the agonistic activity of 135H11 could be enhanced by biotin conjugation followed by complex formation with streptavidin. Therefore, we measured the agonistic EphA2 activity of 135H11-biotin (147B5) at various agent/streptavidin ratios, side by side with 135H12, and a scrambled version of 147B5 in pancreatic- and breast-cancer cell lines. The (147B5)n-streptavidin complexes (when n = 2, 3, 4, but not when n = 1) induced a strong receptor degradation effect in both cell lines compared to 135H12 or the (scrambled-147B5)4-streptavidin complex as a control, indicating that multimerization of the targeting agent resulted in an increased ability to cause receptor clustering and internalization. Subsequently, we prepared an Alexa-Fluor-streptavidin conjugate to demonstrate that (147B5)4-AF-streptavidin, but not the scrambled equivalent complex, concentrates in pancreatic and breast cancers in orthotopic nude-mouse models. Hence, we conclude that these novel targeting agents, with proper derivatization with imaging reagents or chemotherapy, can be used as diagnostics, and/or to deliver chemotherapy selectively to EphA2-expressing tumors.
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Affiliation(s)
- Parima Udompholkul
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, 900 University Avenue, Riverside, CA 92521, USA; (P.U.); (C.B.); (L.G.)
| | - Carlo Baggio
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, 900 University Avenue, Riverside, CA 92521, USA; (P.U.); (C.B.); (L.G.)
| | - Luca Gambini
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, 900 University Avenue, Riverside, CA 92521, USA; (P.U.); (C.B.); (L.G.)
| | - Yu Sun
- AntiCancer Inc., 7917 Ostrow St., San Diego, CA 92111, USA; (Y.S.); (M.Z.); (R.M.H.)
- Department of Surgery, University of California, 9300 Campus Point Dr #7220, La Jolla, San Diego, CA 92037, USA
| | - Ming Zhao
- AntiCancer Inc., 7917 Ostrow St., San Diego, CA 92111, USA; (Y.S.); (M.Z.); (R.M.H.)
| | - Robert M. Hoffman
- AntiCancer Inc., 7917 Ostrow St., San Diego, CA 92111, USA; (Y.S.); (M.Z.); (R.M.H.)
- Department of Surgery, University of California, 9300 Campus Point Dr #7220, La Jolla, San Diego, CA 92037, USA
| | - Maurizio Pellecchia
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, 900 University Avenue, Riverside, CA 92521, USA; (P.U.); (C.B.); (L.G.)
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Salem AF, Gambini L, Billet S, Sun Y, Oshiro H, Zhao M, Hoffman RM, Bhowmick NA, Pellecchia M. Prostate Cancer Metastases Are Strongly Inhibited by Agonistic Epha2 Ligands in an Orthotopic Mouse Model. Cancers (Basel) 2020; 12:cancers12102854. [PMID: 33023262 PMCID: PMC7600344 DOI: 10.3390/cancers12102854] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 09/27/2020] [Accepted: 09/28/2020] [Indexed: 11/29/2022] Open
Abstract
Simple Summary We demonstrate that pro-oncogenic EphA2 (ephrin type-A receptor 2) expression is activated in aggressive prostate cancers, and in mouse models of prostate cancers that are treated with enzalutamide. We also demonstrate in mouse models, that agonistic EphA2 targeting agents are very effective in suppressing cell migration and tumor metastases, hence anticipating the possible use of such agents in innovative anti-metastatic therapeutic modalities. Abstract The EphA2 tyrosine kinase receptor is highly expressed in several types of solid tumors. In our recent studies, we targeted EphA2 in pancreatic cancer with agonistic agents and demonstrated that suppression of EphA2 significantly reduced cancer-cell migration in cell-based assays. In the present study, we focused on targeting EphA2 in prostate cancer. While not all prostate cancers express EphA2, we showed that enzalutamide induced EphA2 expression in prostate cancer cells and in a patient-derived xenograft (PDX) animal model, which provides further impetus to target EphA2 in prostate cancer. Western blot studies showed that agonistic dimeric synthetic (135H12) and natural (ephrinA1-Fc) ligands effectively degraded EphA2 receptor in the prostate cancer cell line PC-3. The agents also delayed cell migration of prostate cancer (PC-3) cells, while an in vivo PC-3 orthotopic metastatic nude-mouse model also revealed that administration of ephrinA1-Fc or 135H12 strongly reduced metastases. The present study further validates EphA2 as an important target in metastatic prostate cancer treatment. Our results should incentivize further efforts aimed at developing potent and effective EphA2 synthetic agonistic agents for the treatment of EphA2-driven aggressive metastatic tumors including prostate, pancreatic, and breast cancer.
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Affiliation(s)
- Ahmed F. Salem
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, 900 University Avenue, Riverside, CA 92521, USA; (A.F.S.); (L.G.)
| | - Luca Gambini
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, 900 University Avenue, Riverside, CA 92521, USA; (A.F.S.); (L.G.)
| | - Sandrine Billet
- Department of Medicine, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA; (S.B.); (N.A.B.)
| | - Yu Sun
- AntiCancer Inc., 7917 Ostrow St., San Diego, CA 92111, USA; (Y.S.); (H.O.); (M.Z.); (R.M.H.)
- Department of Surgery, University of California, San Diego, CA 92037, USA
| | - Hiromichi Oshiro
- AntiCancer Inc., 7917 Ostrow St., San Diego, CA 92111, USA; (Y.S.); (H.O.); (M.Z.); (R.M.H.)
| | - Ming Zhao
- AntiCancer Inc., 7917 Ostrow St., San Diego, CA 92111, USA; (Y.S.); (H.O.); (M.Z.); (R.M.H.)
| | - Robert M. Hoffman
- AntiCancer Inc., 7917 Ostrow St., San Diego, CA 92111, USA; (Y.S.); (H.O.); (M.Z.); (R.M.H.)
- Department of Surgery, University of California, San Diego, CA 92037, USA
| | - Neil A. Bhowmick
- Department of Medicine, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA; (S.B.); (N.A.B.)
| | - Maurizio Pellecchia
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, 900 University Avenue, Riverside, CA 92521, USA; (A.F.S.); (L.G.)
- Correspondence: ; Tel.: +1-951-8277829
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London M, Gallo E. The EphA2 and cancer connection: potential for immune-based interventions. Mol Biol Rep 2020; 47:8037-8048. [PMID: 32990903 DOI: 10.1007/s11033-020-05767-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 08/28/2020] [Indexed: 12/18/2022]
Abstract
The Eph (erythropoietin-producing human hepatocellular) receptors form the largest known subfamily of receptor tyrosine kinases. These receptors interact with membrane-bound ephrin ligands via direct cell-cell interactions resulting in bi-directional activation of signal pathways. Importantly, the Eph receptors play critical roles in embryonic tissue organization and homeostasis, and in the maintenance of adult processes such as long-term potentiation, angiogenesis, and stem cell differentiation. The Eph receptors also display properties of both tumor promoters and suppressors depending on the cellular context. Characterization of EphA2 receptor in regard to EphA2 dysregulation has revealed associations with various pathological processes, especially cancer. The analysis of various tumor types generally identify EphA2 receptor as overexpressed and/or mutated, and for certain types of cancers EphA2 is linked with poor prognosis and decreased patient survival. Thus, here we highlight the role of EphA2 in malignant tissues that are specific to cancer; these include glioblastoma multiforme, prostate cancer, ovarian and uterine cancers, gastric carcinoma, melanoma, and breast cancer. Due to its large extracellular domain, therapeutic targeting of EphA2 with monoclonal antibodies (mAbs), which may function as inhibitors of ligand activation or as molecular agonists, has been an oft-attempted strategy. Therefore, we review the most current mAb-based therapies against EphA2 expressing cancers currently in pre-clinical and/or clinical stages. Finally, we discuss the latest peptides and cyclical-peptides that function as selective agonists for EphA2 receptor.
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Affiliation(s)
- Max London
- Department of Molecular Genetics, University of Toronto, Donnelly Centre, 160 College Street, Toronto, ON, M5S 3E1, Canada
| | - Eugenio Gallo
- Department of Molecular Genetics, University of Toronto, Donnelly Centre, 160 College Street, Toronto, ON, M5S 3E1, Canada.
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Salem AF, Gambini L, Udompholkul P, Baggio C, Pellecchia M. Therapeutic Targeting of Pancreatic Cancer via EphA2 Dimeric Agonistic Agents. Pharmaceuticals (Basel) 2020; 13:ph13050090. [PMID: 32397624 PMCID: PMC7281375 DOI: 10.3390/ph13050090] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 04/30/2020] [Accepted: 05/05/2020] [Indexed: 01/05/2023] Open
Abstract
Recently, we reported on potent EphA2 targeting compounds and demonstrated that dimeric versions of such agents can exhibit remarkably increased agonistic activity in cellular assays compared to the monomers. Here we further characterize the activity of dimeric compounds at the structural, biochemical, and cellular level. In particular, we propose a structural model for the mechanism of receptor activation by dimeric agents and characterize the effect of most potent compounds in inducing EphA2 activation and degradation in a pancreatic cancer cell line. These cellular studies indicate that the pro-migratory effects induced by the receptor can be reversed in EphA2 knockout cells, by treatment with either a dimeric natural ligand (ephrinA1-Fc), or by our synthetic agonistic dimers. Based on these data we conclude that the proposed agents hold great potential as possible therapeutics in combination with standard of care, where these could help suppressing a major driver for cell migration and tumor metastases. Finally, we also found that, similar to ephrinA1-Fc, dimeric agents cause a sustained internalization of the EphA2 receptor, hence, with proper derivatizations, these could also be used to deliver chemotherapy selectively to pancreatic tumors.
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11
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Giorgio C, Zanotti I, Lodola A, Tognolini M. Ephrin or not? Six tough questions on Eph targeting. Expert Opin Ther Targets 2020; 24:403-415. [PMID: 32197575 DOI: 10.1080/14728222.2020.1745187] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Introduction: The Eph-ephrin is a cell-cell communication system generating a forward signal in cell expressing Eph receptors and a reverse signal in ephrin-ligand expressing cells. While clearly involved in the insurgence and progression of cancer, the understanding of the molecular mechanisms regulated by this system needs development; this is a hurdle to the development of therapeutic strategies that can target the Eph receptors and/or their ephrin ligands.Areas covered: We have taken the opportunity to share some key questions on the most effective strategies to target the Eph-ephrin system. This article is based on our experience of the field and therefore is a Perspective and not comprehensive examination of the literature.Expert opinion: Targeting of the Eph-ephrin system has emerged as a potentially valuable approach for cancer therapy. Pharmacological tools have been reported in the last 15 years and these include forward signaling blockers such as kinases inhibitors and antagonists of forward and reverse signaling. Also, biologics including antibodies and recombinant proteins have been developed and some have reached early clinical stages. Data deem the Eph-ephrin system as a signaling axis that is an elusive target. A better understanding of the basic pharmacology behind the activity of available agents and a comprehensive knowledge of the ephrin biology are necessary. We are looking forward to knowing the opinion of the readers.
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Affiliation(s)
- Carmine Giorgio
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università di Parma, Parma, Italy
| | - Ilaria Zanotti
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università di Parma, Parma, Italy
| | - Alessio Lodola
- Dipartimento di Scienze degli Alimenti e del Farmaco, Università di Parma, Parma, Italy
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Incerti M, Russo S, Corrado M, Giorgio C, Ballabeni V, Chiodelli P, Rusnati M, Scalvini L, Callegari D, Castelli R, Vacondio F, Ferlenghi F, Tognolini M, Lodola A. Optimization of EphA2 antagonists based on a lithocholic acid core led to the identification of UniPR505, a new 3α-carbamoyloxy derivative with antiangiogenetic properties. Eur J Med Chem 2020; 189:112083. [PMID: 32000051 DOI: 10.1016/j.ejmech.2020.112083] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 01/16/2020] [Accepted: 01/19/2020] [Indexed: 11/24/2022]
Abstract
The EphA2 receptor has been validated in animal models as new target for treating tumors depending on angiogenesis and vasculogenic mimicry. In the present work, we extended our current knowledge on structure-activity relationship (SAR) data of two related classes of antagonists of the EphA2 receptor, namely 5β-cholan-24-oic acids and 5β-cholan-24-oyl l-β-homotryptophan conjugates, with the aim to develop new antiangiogenic compounds able to efficiently prevent the formation of blood vessels. As a result of our exploration, we identified UniPR505, N-[3α-(Ethylcarbamoyl)oxy-5β-cholan-24-oyl]-l-β-homo-tryptophan (compound 14), as a submicromolar antagonist of the EphA2 receptor capable to block EphA2 phosphorylation and to inhibit neovascularization in a chorioallantoic membrane (CAM) assay.
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Affiliation(s)
- Matteo Incerti
- Department of Food and Drug, University of Parma, 43124, Parma, Italy
| | - Simonetta Russo
- Department of Food and Drug, University of Parma, 43124, Parma, Italy
| | - Miriam Corrado
- Department of Food and Drug, University of Parma, 43124, Parma, Italy
| | - Carmine Giorgio
- Department of Food and Drug, University of Parma, 43124, Parma, Italy
| | - Vigilio Ballabeni
- Department of Food and Drug, University of Parma, 43124, Parma, Italy
| | - Paola Chiodelli
- Department of Molecular and Translational Medicine, University of Brescia, 25123, Brescia, Italy
| | - Marco Rusnati
- Department of Molecular and Translational Medicine, University of Brescia, 25123, Brescia, Italy
| | - Laura Scalvini
- Department of Food and Drug, University of Parma, 43124, Parma, Italy
| | | | - Riccardo Castelli
- Department of Food and Drug, University of Parma, 43124, Parma, Italy
| | - Federica Vacondio
- Department of Food and Drug, University of Parma, 43124, Parma, Italy
| | | | | | - Alessio Lodola
- Department of Food and Drug, University of Parma, 43124, Parma, Italy.
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13
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Lingasamy P, Tobi A, Haugas M, Hunt H, Paiste P, Asser T, Rätsep T, Kotamraju VR, Bjerkvig R, Teesalu T. Bi-specific tenascin-C and fibronectin targeted peptide for solid tumor delivery. Biomaterials 2019; 219:119373. [PMID: 31374479 DOI: 10.1016/j.biomaterials.2019.119373] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 07/08/2019] [Accepted: 07/18/2019] [Indexed: 01/15/2023]
Abstract
Oncofetal fibronectin (FN-EDB) and tenascin-C C domain (TNC-C) are nearly absent in extracellular matrix of normal adult tissues but upregulated in malignant tissues. Both FN-EDB and TNC-C are developed as targets of antibody-based therapies. Here we used peptide phage biopanning to identify a novel targeting peptide (PL1, sequence: PPRRGLIKLKTS) that interacts with both FN-EDB and TNC-C. Systemic PL1-functionalized model nanoscale payloads [iron oxide nanoworms (NWs) and metallic silver nanoparticles] homed to glioblastoma (GBM) and prostate carcinoma xenografts, and to non-malignant angiogenic neovessels induced by VEGF-overexpression. Antibody blockage experiments demonstrated that PL1 tumor homing involved interactions with both receptor proteins. Treatment of GBM mice with PL1-targeted model therapeutic nanocarrier (NWs loaded with a proapoptotic peptide) resulted in reduced tumor growth and increased survival, whereas treatment with untargeted particles had no effect. PL1 peptide may have applications as an affinity ligand for delivery of diagnostic and therapeutic compounds to microenvironment of solid tumors.
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Affiliation(s)
- Prakash Lingasamy
- Laboratory of Cancer Biology, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, 50411, Tartu, Estonia
| | - Allan Tobi
- Laboratory of Cancer Biology, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, 50411, Tartu, Estonia
| | - Maarja Haugas
- Laboratory of Cancer Biology, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, 50411, Tartu, Estonia
| | - Hedi Hunt
- Laboratory of Cancer Biology, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, 50411, Tartu, Estonia
| | - Päärn Paiste
- Department of Geology, University of Tartu, 50411, Tartu, Estonia
| | - Toomas Asser
- Department of Neurosurgery, Tartu University Hospital, 50406, Tartu, Estonia
| | - Tõnu Rätsep
- Department of Neurosurgery, Tartu University Hospital, 50406, Tartu, Estonia
| | - Venkata Ramana Kotamraju
- Cancer Research Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, 92037, CA, USA; Center for Nanomedicine and Department of Cell, Molecular and Developmental Biology, University of California, Santa Barbara, Santa Barbara, 93106, CA, USA
| | - Rolf Bjerkvig
- Department of Biomedicine Translational Cancer Research, University of Bergen, 5020, Bergen, Norway
| | - Tambet Teesalu
- Laboratory of Cancer Biology, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, 50411, Tartu, Estonia; Cancer Research Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, 92037, CA, USA; Center for Nanomedicine and Department of Cell, Molecular and Developmental Biology, University of California, Santa Barbara, Santa Barbara, 93106, CA, USA.
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14
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Gomez-Soler M, Petersen Gehring M, Lechtenberg BC, Zapata-Mercado E, Hristova K, Pasquale EB. Engineering nanomolar peptide ligands that differentially modulate EphA2 receptor signaling. J Biol Chem 2019; 294:8791-8805. [PMID: 31015204 DOI: 10.1074/jbc.ra119.008213] [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: 02/26/2019] [Revised: 04/18/2019] [Indexed: 11/06/2022] Open
Abstract
The EPH receptor A2 (EphA2) tyrosine kinase plays an important role in a plethora of biological and disease processes, ranging from angiogenesis and cancer to inflammation and parasitic infections. EphA2 is therefore considered an important drug target. Two short peptides previously identified by phage display, named YSA and SWL, are widely used as EphA2-targeting agents owing to their high specificity for this receptor. However, these peptides have only modest (micromolar) potency. Lack of structural information on the binding interactions of YSA and SWL with the extracellular EphA2 ligand-binding domain (LBD) has for many years precluded structure-guided improvements. We now report the high-resolution (1.53-2.20 Å) crystal structures of the YSA peptide and several of its improved derivatives in complex with the EphA2 LBD, disclosing that YSA targets the ephrin-binding pocket of EphA2 and mimics binding features of the ephrin-A ligands. The structural information obtained enabled iterative peptide modifications conferring low nanomolar potency. Furthermore, contacts observed in the crystal structures shed light on how C-terminal features can convert YSA derivatives from antagonists to agonists that likely bivalently interact with two EphA2 molecules to promote receptor oligomerization, autophosphorylation, and downstream signaling. Consistent with this model, quantitative FRET measurements in live cells revealed that the peptide agonists promote the formation of EphA2 oligomeric assemblies. Our findings now enable rational strategies to differentially modify EphA2 signaling toward desired outcomes by using appropriately engineered peptides. Such peptides could be used as research tools to interrogate EphA2 function and to develop pharmacological leads.
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Affiliation(s)
- Maricel Gomez-Soler
- From the Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California 92037 and
| | - Marina Petersen Gehring
- From the Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California 92037 and
| | - Bernhard C Lechtenberg
- From the Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California 92037 and
| | - Elmer Zapata-Mercado
- the Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, Maryland 21218
| | - Kalina Hristova
- the Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, Maryland 21218
| | - Elena B Pasquale
- From the Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California 92037 and
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15
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Patil MA, Upadhyay AK, Hernandez-Lagunas L, Good R, Carpenter TC, Sucharov CC, Nozik-Grayck E, Kompella UB. Targeted delivery of YSA-functionalized and non-functionalized polymeric nanoparticles to injured pulmonary vasculature. ARTIFICIAL CELLS NANOMEDICINE AND BIOTECHNOLOGY 2018; 46:S1059-S1066. [PMID: 30450979 DOI: 10.1080/21691401.2018.1528984] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Ephrin type-A receptor 2 (EphA2) is a transmembrane receptor which is upregulated in injured lungs, including those treated with bleomycin. YSA peptide (YSAYPDSVPMMS), a mimic of ephrin ligands, binds to EphA2 receptors on cell surface with high affinity. In this study, we assessed the ability of YSA-functionalized and non-functionalized poly (dl-lactide-co-glycolide) (PLGA) nanoparticles to enhance delivery to bleomycin treated cultured vascular endothelial cells and, in a bleomycin induced lung injury mouse model. Nanoparticles were loaded with a lipophilic fluorescent dye. Human umbilical vein endothelial cells (HUVEC) with or without 2-day bleomycin pretreatment (25 µg/ml) and adult mice with or without intratracheal instillation of bleomycin (0.1 U) were dosed with nanoparticles. Mice received nanoparticles via tail vein injection 4 days after bleomycin treatment. Three days after nanoparticle injection, tissues (lung, heart, kidney, spleen, liver, brain, eyes and whole blood) were harvested and quantified for fluorescence using IVIS imaging. Mean particle uptake increased with time and concentration for both types of particles in HUVEC, with the uptake being higher for YSA-functionalized nanoparticles. Bleomycin treatment increased the 3-h uptake of both types of nanoparticles in HUVEC by about two-fold, with the YSA-functionalized nanoparticle uptake being 1.66-fold compared to non-functionalized nanoparticles (p < .05). In mice, bleomycin injury resulted in 2.3- and 4.7-fold increase in the lung levels of non-functionalized and YSA-functionalized nanoparticles (p < .05), respectively, although the differences between the two particle types were not significant. In conclusion, PLGA nanoparticle delivery to cultured vascular endothelial cells and mouse lungs in vivo is higher following bleomycin treatment, with the delivery tending to be higher for YSA functionalized nanoparticles.
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Affiliation(s)
- Madhoosudan A Patil
- a Department of Pharmaceutical Sciences , University of Colorado Anschutz Medical Campus , Aurora , CO , USA
| | - Arun K Upadhyay
- a Department of Pharmaceutical Sciences , University of Colorado Anschutz Medical Campus , Aurora , CO , USA
| | - Laura Hernandez-Lagunas
- b Cardiovascular Pulmonary Research Laboratories, Department of Pediatrics and Medicine , University of Colorado Denver , Denver , CO , USA
| | - Ryan Good
- b Cardiovascular Pulmonary Research Laboratories, Department of Pediatrics and Medicine , University of Colorado Denver , Denver , CO , USA
| | - Todd C Carpenter
- c Division of Pediatric Critical Care Medicine, Department of Pediatrics , University of Colorado School of Medicine , Aurora , CO , USA
| | - Carmen C Sucharov
- d Division of Cardiology, Department of Medicine , University of Colorado Anschutz Medical Campus , Aurora , CO , USA
| | - Eva Nozik-Grayck
- b Cardiovascular Pulmonary Research Laboratories, Department of Pediatrics and Medicine , University of Colorado Denver , Denver , CO , USA.,c Division of Pediatric Critical Care Medicine, Department of Pediatrics , University of Colorado School of Medicine , Aurora , CO , USA
| | - Uday B Kompella
- a Department of Pharmaceutical Sciences , University of Colorado Anschutz Medical Campus , Aurora , CO , USA.,e Department of Ophthalmology , University of Colorado Anschutz Medical Campus , Aurora , Colorado.,f Department of Bioengineering , University of Colorado Anschutz Medical Campus , Aurora , CO , USA.,g Colorado Center for Nanomedicine and Nanosafety, University of Colorado Anschutz Medical Campus , Aurora , CO , USA
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16
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Möser C, Lorenz JS, Sajfutdinow M, Smith DM. Pinpointed Stimulation of EphA2 Receptors via DNA-Templated Oligovalence. Int J Mol Sci 2018; 19:ijms19113482. [PMID: 30404153 PMCID: PMC6274923 DOI: 10.3390/ijms19113482] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 11/02/2018] [Indexed: 11/20/2022] Open
Abstract
DNA nanostructures enable the attachment of functional molecules to nearly any unique location on their underlying structure. Due to their single-base-pair structural resolution, several ligands can be spatially arranged and closely controlled according to the geometry of their desired target, resulting in optimized binding and/or signaling interactions. Here, the efficacy of SWL, an ephrin-mimicking peptide that binds specifically to EphrinA2 (EphA2) receptors, increased by presenting up to three of these peptides on small DNA nanostructures in an oligovalent manner. Ephrin signaling pathways play crucial roles in tumor development and progression. Moreover, Eph receptors are potential targets in cancer diagnosis and treatment. Here, the quantitative impact of SWL valency on binding, phosphorylation (key player for activation) and phenotype regulation in EphA2-expressing prostate cancer cells was demonstrated. EphA2 phosphorylation was significantly increased by DNA trimers carrying three SWL peptides compared to monovalent SWL. In comparison to one of EphA2’s natural ligands ephrin-A1, which is known to bind promiscuously to multiple receptors, pinpointed targeting of EphA2 by oligovalent DNA-SWL constructs showed enhanced cell retraction. Overall, we show that DNA scaffolds can increase the potency of weak signaling peptides through oligovalent presentation and serve as potential tools for examination of complex signaling pathways.
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Affiliation(s)
- Christin Möser
- DNA Nanodevices Unit, Department Diagnostics, Fraunhofer Institute for Cell Therapy and Immunology IZI, 04103 Leipzig, Germany.
- Institute of Biochemistry and Biology, Faculty of Science, University of Potsdam, 14476 Potsdam, Germany.
| | - Jessica S Lorenz
- DNA Nanodevices Unit, Department Diagnostics, Fraunhofer Institute for Cell Therapy and Immunology IZI, 04103 Leipzig, Germany.
- Peter Debye Institute for Soft Matter Physics, Faculty of Physics and Earth Sciences, University of Leipzig, 04103 Leipzig, Germany.
| | - Martin Sajfutdinow
- DNA Nanodevices Unit, Department Diagnostics, Fraunhofer Institute for Cell Therapy and Immunology IZI, 04103 Leipzig, Germany.
- Fraunhofer Project Center "Microelectronic and Optical Systems for Biomedicine" (MEOS), 99099 Erfurt, Germany.
| | - David M Smith
- DNA Nanodevices Unit, Department Diagnostics, Fraunhofer Institute for Cell Therapy and Immunology IZI, 04103 Leipzig, Germany.
- Peter Debye Institute for Soft Matter Physics, Faculty of Physics and Earth Sciences, University of Leipzig, 04103 Leipzig, Germany.
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17
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Gambini L, Salem AF, Udompholkul P, Tan XF, Baggio C, Shah N, Aronson A, Song J, Pellecchia M. Structure-Based Design of Novel EphA2 Agonistic Agents with Nanomolar Affinity in Vitro and in Cell. ACS Chem Biol 2018; 13:2633-2644. [PMID: 30110533 DOI: 10.1021/acschembio.8b00556] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
EphA2 overexpression is invariably associated with poor prognosis and development of aggressive metastatic cancers in pancreatic, prostate, lung, ovarian, and breast cancers and melanoma. Recent efforts from our laboratories identified a number of agonistic peptides targeting the ligand-binding domain of the EphA2 receptor. The individual agents, however, were still relatively weak in affinities (micromolar range) that precluded detailed structural studies on the mode of action. Using a systematic optimization of the 12-mer peptide mimetic 123B9, we were able to first derive an agent that displayed a submicromolar affinity for the receptor. This agent enabled cocrystallization with the EphA2 ligand-binding domain providing for the first time the structural basis for their agonistic mechanism of action. In addition, the atomic coordinates of the complex enabled rapid iterations of structure-based optimizations that resulted in a novel agonistic agent, named 135H11, with a nanomolar affinity for the receptor, as demonstrated by in vitro binding assays (isothermal titration calorimetry measurements), and a biochemical displacement assay. As we have recently demonstrated, the cellular activity of these agents is further increased by synthesizing dimeric versions of the compounds. Hence, we report that a dimeric version of 135H11 is extremely effective at low nanomolar concentrations to induce cellular receptor activation, internalization, and inhibition of cell migration in a pancreatic cancer cell line. Given the pivotal role of EphA2 in tumor growth, angiogenesis, drug resistance, and metastasis, these agents, and the associated structural studies, provide significant advancements in the field for the development of novel EphA2-targeting therapeutics or diagnostics.
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Affiliation(s)
- Luca Gambini
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, 900 University Avenue, Riverside, California 92521, United States
| | - Ahmed F. Salem
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, 900 University Avenue, Riverside, California 92521, United States
| | - Parima Udompholkul
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, 900 University Avenue, Riverside, California 92521, United States
| | - Xiao-Feng Tan
- Department of Biochemistry, College of Natural and Agricultural Sciences, University of California Riverside, 900 University Avenue, Riverside, California 92521, United States
| | - Carlo Baggio
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, 900 University Avenue, Riverside, California 92521, United States
| | - Neh Shah
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, 900 University Avenue, Riverside, California 92521, United States
| | - Alexander Aronson
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, 900 University Avenue, Riverside, California 92521, United States
| | - Jikui Song
- Department of Biochemistry, College of Natural and Agricultural Sciences, University of California Riverside, 900 University Avenue, Riverside, California 92521, United States
| | - Maurizio Pellecchia
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, 900 University Avenue, Riverside, California 92521, United States
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18
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Mercurio FA, Pirone L, Di Natale C, Marasco D, Pedone EM, Leone M. Sam domain-based stapled peptides: Structural analysis and interaction studies with the Sam domains from the EphA2 receptor and the lipid phosphatase Ship2. Bioorg Chem 2018; 80:602-610. [PMID: 30036816 DOI: 10.1016/j.bioorg.2018.07.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 07/06/2018] [Accepted: 07/12/2018] [Indexed: 12/27/2022]
Abstract
Sam (Sterile alpha motif) domains represent small helical protein-protein interaction modules which play versatile functions in different cellular processes. The Sam domain from the EphA2 receptor binds the Sam domain of the lipid phosphatase Ship2 and this interaction modulates receptor endocytosis and degradation primarily generating pro-oncogenic effects in cell. To identify molecule antagonists of the EphA2-Sam/Ship2-Sam complex with anti-cancer activity, we focused on hydrocarbon helical stapled peptides. EphA2-Sam and one of its interactors (i.e., the first Sam domain of the adaptor protein Odin) were used as model systems for peptide design. Increase in helicity in the stapled peptides, with respect to the corresponding linear/native-like regions, was proved by structural studies conducted through CD (Circular Dichroism) and NMR (Nuclear Magnetic Resonance). Interestingly, interaction assays by means of NMR, SPR (Surface Plasmon Resonance) and MST (MicroScale Thermophoresis) techniques led to the discovery of a novel ligand of Ship2-Sam.
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Affiliation(s)
- Flavia Anna Mercurio
- Institute of Biostructures and Bioimaging (CNR), Naples, Italy; InterUniversity Research Centre on Bioactive Peptides (CIRPEB), University of Naples Federico II, Naples, Italy
| | - Luciano Pirone
- Institute of Biostructures and Bioimaging (CNR), Naples, Italy; InterUniversity Research Centre on Bioactive Peptides (CIRPEB), University of Naples Federico II, Naples, Italy
| | | | - Daniela Marasco
- Institute of Biostructures and Bioimaging (CNR), Naples, Italy; InterUniversity Research Centre on Bioactive Peptides (CIRPEB), University of Naples Federico II, Naples, Italy; University of Naples Federico II, Department of Pharmacy, Naples, Italy
| | - Emilia Maria Pedone
- Institute of Biostructures and Bioimaging (CNR), Naples, Italy; InterUniversity Research Centre on Bioactive Peptides (CIRPEB), University of Naples Federico II, Naples, Italy
| | - Marilisa Leone
- Institute of Biostructures and Bioimaging (CNR), Naples, Italy; InterUniversity Research Centre on Bioactive Peptides (CIRPEB), University of Naples Federico II, Naples, Italy.
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19
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Salem AF, Wang S, Billet S, Chen JF, Udompholkul P, Gambini L, Baggio C, Tseng HR, Posadas EM, Bhowmick NA, Pellecchia M. Reduction of Circulating Cancer Cells and Metastases in Breast-Cancer Models by a Potent EphA2-Agonistic Peptide-Drug Conjugate. J Med Chem 2018; 61:2052-2061. [PMID: 29470068 PMCID: PMC5907794 DOI: 10.1021/acs.jmedchem.7b01837] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
![]()
EphA2
overexpression has been associated with metastasis in multiple
cancer types, including melanomas and ovarian, prostate, lung, and
breast cancers. We have recently proposed the development of peptide–drug
conjugates (PDCs) using agonistic EphA2-targeting agents, such as
the YSA peptide or its optimized version, 123B9. Although our studies
indicated that YSA– and 123B9–drug conjugates can selectively
deliver cytotoxic drugs to cancer cells in vivo, the relatively low
cellular agonistic activities (i.e., the high micromolar concentrations
required) of the agents toward the EphA2 receptor remained a limiting
factor to the further development of these PDCs in the clinic. Here,
we report that a dimeric version of 123B9 can induce receptor activation
at nanomolar concentrations. Furthermore, we demonstrated that the
conjugation of dimeric 123B9 with paclitaxel is very effective at
targeting circulating tumor cells and inhibiting lung metastasis in
breast-cancer models. These studies represent an important step toward
the development of effective EphA2-targeting PDCs.
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Affiliation(s)
- Ahmed F Salem
- Division of Biomedical Sciences, School of Medicine , University of California, Riverside , 900 University Avenue , Riverside , California 92521 , United States
| | - Si Wang
- Sanford-Burnham-Prebys Medical Discovery Institute , 10901 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Sandrine Billet
- Department of Medicine , Cedars-Sinai Medical Center , 8700 Beverly Boulevard , Los Angeles , California 90048 , United States
| | - Jie-Fu Chen
- Department of Medicine , Cedars-Sinai Medical Center , 8700 Beverly Boulevard , Los Angeles , California 90048 , United States
| | - Parima Udompholkul
- Division of Biomedical Sciences, School of Medicine , University of California, Riverside , 900 University Avenue , Riverside , California 92521 , United States
| | - Luca Gambini
- Division of Biomedical Sciences, School of Medicine , University of California, Riverside , 900 University Avenue , Riverside , California 92521 , United States
| | - Carlo Baggio
- Division of Biomedical Sciences, School of Medicine , University of California, Riverside , 900 University Avenue , Riverside , California 92521 , United States
| | - Hsian-Rong Tseng
- Department of Molecular & Medical Pharmacology , University of California, Los Angeles , 570 Westwood Plaza , Los Angeles , California 90095 , United States
| | - Edwin M Posadas
- Department of Medicine , Cedars-Sinai Medical Center , 8700 Beverly Boulevard , Los Angeles , California 90048 , United States
| | - Neil A Bhowmick
- Department of Medicine , Cedars-Sinai Medical Center , 8700 Beverly Boulevard , Los Angeles , California 90048 , United States.,Department of Research , Greater Los Angeles Veterans Administration , Los Angeles , California 90073 , United States
| | - Maurizio Pellecchia
- Division of Biomedical Sciences, School of Medicine , University of California, Riverside , 900 University Avenue , Riverside , California 92521 , United States
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20
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The EphA2 receptor is activated through induction of distinct, ligand-dependent oligomeric structures. Commun Biol 2018; 1:15. [PMID: 30271902 PMCID: PMC6123813 DOI: 10.1038/s42003-018-0017-7] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 01/28/2018] [Indexed: 01/19/2023] Open
Abstract
The EphA2 receptor tyrosine kinase is capable of activating multiple diverse signaling pathways with roles in processes such as tissue homeostasis and cancer. EphA2 is known to form activated oligomers in the presence of ephrin-A ligands. Here, we characterize the lateral interactions between full-length EphA2 molecules in the plasma membrane in the presence of three types of ligands (dimeric ephrinA1-Fc, monomeric ephrinA1, and an engineered peptide ligand) as well as in the absence of ligand, using a quantitative FRET technique. The data show that EphA2 forms higher-order oligomers and two different types of dimers that all lead to increased EphA2 tyrosine phosphorylation, which is indicative of increased kinase-dependent signaling. We find that different ligands stabilize conformationally distinct oligomers that are assembled through two different interfaces. Our results suggest that these different oligomeric assemblies could have distinct signaling properties, contributing to the diverse activities of the EphA2 receptor. Deo Singh et al. use Fully Quantified Spectral Imaging-FRET to show that the EphA2 receptor forms dimers or higher order oligomers depending on the type of ligand, and that different ligands stabilize EphA2 dimers through distinct interfaces. These findings may explain how EphA2 activates diverse signaling pathways.
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21
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Zhao J, Zhao F, Wang X, Fan X, Wu G. Secondary nuclear targeting of mesoporous silica nano-particles for cancer-specific drug delivery based on charge inversion. Oncotarget 2018; 7:70100-70112. [PMID: 27661121 PMCID: PMC5342538 DOI: 10.18632/oncotarget.12149] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 09/14/2016] [Indexed: 11/25/2022] Open
Abstract
A novel multifunctional nano-drug delivery system based on reversal of peptide charge was successfully developed for anticancer drug delivery and imaging. Mesoporous silica nano-particles (MSN) ~50 nm in diameter were chosen as the drug reservoirs, and their surfaces were modified with HIV-1 transactivator peptide-fluorescein isothiocyanate (TAT-FITC) and YSA-BHQ1. The short TAT peptide labeled with FITC was used to facilitate intranuclear delivery, while the YSA peptide tagged with the BHQ1 quencher group was used to specifically bind to the tumor EphA2 membrane receptor. Citraconic anhydride (Cit) was used to invert the charge of the TAT peptide in neutral or weak alkaline conditions so that the positively charged YSA peptide could combine with the TAT peptide through electrostatic attraction. The FITC fluorescence was quenched by the spatial approach of BHQ1 after the two peptides bound to each other. However, the Cit-amino bond was unstable in the acidic atmosphere, so the positive charge of the TAT peptide was restored and the positively charged YSA moiety was repelled. The FITC fluorescence was recovered after the YSA-BHQ1 moiety was removed, and the TAT peptide led the nano-particles into the nucleolus. This nano-drug delivery system was stable at physiological pH, rapidly released the drug in acidic buffer, and was easily taken up by MCF-7 cells. Compared with free doxorubicin hydrochloride at an equal concentration, this modified MSN loaded with doxorubicin molecules had an equivalent inhibitory effect on MCF-7 cells. This nano-drug delivery system is thus a promising method for simultaneous cancer diagnosis and therapy.
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Affiliation(s)
- Jianwen Zhao
- Center of Clinical Laboratory Medicine of Zhongda Hospital, Southeast University, Nanjing, 210009, China.,Medical School, Southeast University, Nanjing, 210009, China
| | - Fengfeng Zhao
- Medical School, Southeast University, Nanjing, 210009, China
| | - Xiyong Wang
- Medical School, Southeast University, Nanjing, 210009, China
| | - Xiaobo Fan
- Medical School, Southeast University, Nanjing, 210009, China
| | - Guoqiu Wu
- Center of Clinical Laboratory Medicine of Zhongda Hospital, Southeast University, Nanjing, 210009, China.,Medical School, Southeast University, Nanjing, 210009, China
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22
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Kim MA, Yoon HS, Park SH, Kim DY, Pyo A, Kim HS, Min JJ, Hong Y. Engineering of monobody conjugates for human EphA2-specific optical imaging. PLoS One 2017; 12:e0180786. [PMID: 28686661 PMCID: PMC5501600 DOI: 10.1371/journal.pone.0180786] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2017] [Accepted: 06/21/2017] [Indexed: 02/06/2023] Open
Abstract
In a previous study, we developed an E1 monobody specific for the tumor biomarker hEphA2 [PLoS ONE (2015) 10(7): e0132976]. E1 showed potential as a molecular probe for in vitro and in vivo targeting of cancers overexpressing hEphA2. In the present study, we constructed expression vectors for E1 conjugated to optical reporters such as Renilla luciferase variant 8 (Rluc8) or enhanced green fluorescent protein (EGFP) and purified such recombinant proteins by affinity chromatography in E. coli. E1-Rluc8 and E1-EGFP specifically bound to hEphA2 in human prostate cancer PC3 cells but not in human cervical cancer HeLa cells, which express hEphA2 at high and low levels, respectively. These recombinant proteins maintained >40% activity in mouse serum at 24 h. In vivo optical imaging for 24 h did not detect E1-EGFP signals, whereas E1-Rluc8 showed tumor-specific luminescence signals in PC3 but not in HeLa xenograft mice. E1-Rluc8 signals were detected at 4 h, peaked at 12 h, and were undetectable at 24 h. These results suggest the potential of E1-Rluc8 as an EphA2-specific optical imaging agent.
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MESH Headings
- Animals
- Antibodies, Neoplasm/biosynthesis
- Antibodies, Neoplasm/chemistry
- Biomarkers, Tumor/analysis
- Biomarkers, Tumor/genetics
- Biomarkers, Tumor/metabolism
- Cell Line, Tumor
- Escherichia coli/genetics
- Escherichia coli/metabolism
- Female
- Genes, Reporter
- Genetic Vectors/chemistry
- Genetic Vectors/metabolism
- Green Fluorescent Proteins/genetics
- Green Fluorescent Proteins/metabolism
- HeLa Cells
- Heterografts
- Humans
- Immunoconjugates/chemistry
- Immunoconjugates/metabolism
- Luciferases/genetics
- Luciferases/metabolism
- Male
- Mice, Inbred BALB C
- Mice, Nude
- Optical Imaging
- Organ Specificity
- Protein Engineering
- Receptor, EphA2/analysis
- Receptor, EphA2/genetics
- Receptor, EphA2/metabolism
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/metabolism
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Affiliation(s)
- Min-A Kim
- Department of Microbiology, Chonnam National University Medical School, Gwangju, Republic of Korea
- Department of Molecular Medicine (BK21Plus), Chonnam National University Medical School, Gwangju, Republic of Korea
| | - Hee Seung Yoon
- Department of Molecular Medicine (BK21Plus), Chonnam National University Medical School, Gwangju, Republic of Korea
- Department of Nuclear Medicine, Chonnam National University Medical School, Gwangju, Republic of Korea
| | - Seung-Hwan Park
- Biological Resource Center, Korea Research Institute of Bioscience & Biotechnology (KRIBB), Jeongeup, Republic of Korea
| | - Dong-Yeon Kim
- Department of Nuclear Medicine, Chonnam National University Medical School, Gwangju, Republic of Korea
| | - Ayoung Pyo
- Department of Nuclear Medicine, Chonnam National University Medical School, Gwangju, Republic of Korea
| | - Hyeon Sik Kim
- Department of Nuclear Medicine, Chonnam National University Medical School, Gwangju, Republic of Korea
| | - Jung-Joon Min
- Department of Nuclear Medicine, Chonnam National University Medical School, Gwangju, Republic of Korea
| | - Yeongjin Hong
- Department of Microbiology, Chonnam National University Medical School, Gwangju, Republic of Korea
- * E-mail:
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23
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Barquilla A, Lamberto I, Noberini R, Heynen-Genel S, Brill LM, Pasquale EB. Protein kinase A can block EphA2 receptor-mediated cell repulsion by increasing EphA2 S897 phosphorylation. Mol Biol Cell 2016; 27:2757-70. [PMID: 27385333 PMCID: PMC5007095 DOI: 10.1091/mbc.e16-01-0048] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 06/24/2016] [Indexed: 12/18/2022] Open
Abstract
The EphA2 receptor plays multiple roles in cancer through two distinct signaling mechanisms. In a novel cross-talk, the β2-adrenoceptor/cAMP/PKA axis can promote EphA2 pro-oncogenic, ligand-independent signaling, blocking cell repulsion induced by ligand-dependent signaling. PKA emerges as a third kinase, besides AKT and RSK, that can regulate EphA2. The EphA2 receptor tyrosine kinase plays key roles in tissue homeostasis and disease processes such as cancer, pathological angiogenesis, and inflammation through two distinct signaling mechanisms. EphA2 “canonical” signaling involves ephrin-A ligand binding, tyrosine autophosphorylation, and kinase activity; EphA2 “noncanonical” signaling involves phosphorylation of serine 897 (S897) by AKT and RSK kinases. To identify small molecules counteracting EphA2 canonical signaling, we developed a high-content screening platform measuring inhibition of ephrin-A1–induced PC3 prostate cancer cell retraction. Surprisingly, most hits from a screened collection of pharmacologically active compounds are agents that elevate intracellular cAMP by activating G protein–coupled receptors such as the β2-adrenoceptor. We found that cAMP promotes phosphorylation of S897 by protein kinase A (PKA) as well as increases the phosphorylation of several nearby serine/threonine residues, which constitute a phosphorylation hotspot. Whereas EphA2 canonical and noncanonical signaling have been viewed as mutually exclusive, we show that S897 phosphorylation by PKA can coexist with EphA2 tyrosine phosphorylation and block cell retraction induced by EphA2 kinase activity. Our findings reveal a novel paradigm in EphA2 function involving the interplay of canonical and noncanonical signaling and highlight the ability of the β2-adrenoceptor/cAMP/PKA axis to rewire EphA2 signaling in a subset of cancer cells.
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Affiliation(s)
- Antonio Barquilla
- Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037
| | - Ilaria Lamberto
- Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037
| | - Roberta Noberini
- Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037
| | - Susanne Heynen-Genel
- Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037
| | - Laurence M Brill
- Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037
| | - Elena B Pasquale
- Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037 Pathology Department, University of California, San Diego, La Jolla, CA 92093
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24
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Singh DR, Pasquale EB, Hristova K. A small peptide promotes EphA2 kinase-dependent signaling by stabilizing EphA2 dimers. Biochim Biophys Acta Gen Subj 2016; 1860:1922-8. [PMID: 27281300 DOI: 10.1016/j.bbagen.2016.06.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 05/31/2016] [Accepted: 06/03/2016] [Indexed: 12/01/2022]
Abstract
BACKGROUND The EphA2 receptor tyrosine kinase is known to promote cancer cell malignancy in the absence of activation by ephrin ligands. This behavior depends on high EphA2 phosphorylation on Ser897 and low tyrosine phosphorylation, resulting in increased cell migration and invasiveness. We have previously shown that EphA2 forms dimers in the absence of ephrin ligand binding, and that dimerization of unliganded EphA2 can decrease EphA2 Ser897 phosphorylation. We have also identified a small peptide called YSA, which binds EphA2 and competes with the naturally occurring ephrin ligands. METHODS Here, we investigate the effect of YSA on EphA2 dimer stability and EphA2 function using quantitative FRET techniques, Western blotting, and cell motility assays. RESULTS We find that the YSA peptide stabilizes the EphA2 dimer, increases EphA2 Tyr phosphorylation, and decreases both Ser897 phosphorylation and cell migration. CONCLUSIONS The experiments demonstrate that the small peptide ligand YSA reduces EphA2 Ser897 pro-tumorigenic signaling by stabilizing the EphA2 dimer. GENERAL SIGNIFICANCE This work is a proof-of-principle demonstration that EphA2 homointeractions in the plasma membrane can be pharmacologically modulated to decrease the pro-tumorigenic signaling of the receptor.
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Affiliation(s)
- Deo R Singh
- Department of Materials Science and Engineering, Johns Hopkins University, 3400 Charles Street, Baltimore, MD 21218, United States
| | - Elena B Pasquale
- Sanford Burnham Prebys Medical Discovery Institute, 10901 North Torrey Road, La Jolla, San Diego, CA 92037, United States
| | - Kalina Hristova
- Department of Materials Science and Engineering, Johns Hopkins University, 3400 Charles Street, Baltimore, MD 21218, United States.
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25
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Bhunia D, Saha A, Adak A, Das G, Ghosh S. A dual functional liposome specifically targets melanoma cells through integrin and ephrin receptors. RSC Adv 2016. [DOI: 10.1039/c6ra23864e] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
A novel bi-functional liposome delivers docetaxel specifically to melanoma cancer cells targeting integrin (α4β1) and ephrin (EphA2) receptors and enhances the efficacy of docetaxel.
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Affiliation(s)
- Debmalya Bhunia
- Organic & Medicinal Chemistry Division
- CSIR-Indian Institute of Chemical Biology
- Kolkata-700032
- India
| | - Abhijit Saha
- Organic & Medicinal Chemistry Division
- CSIR-Indian Institute of Chemical Biology
- Kolkata-700032
- India
| | - Anindyasundar Adak
- Organic & Medicinal Chemistry Division
- CSIR-Indian Institute of Chemical Biology
- Kolkata-700032
- India
| | - Gaurav Das
- Academy of Scientific and Innovative Research (AcSIR)
- Kolkata 700 032
- India
| | - Surajit Ghosh
- Organic & Medicinal Chemistry Division
- CSIR-Indian Institute of Chemical Biology
- Kolkata-700032
- India
- Academy of Scientific and Innovative Research (AcSIR)
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26
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Echalier C, Kalistratova A, Ciccione J, Lebrun A, Legrand B, Naydenova E, Gagne D, Fehrentz JA, Marie J, Amblard M, Mehdi A, Martinez J, Subra G. Selective homodimerization of unprotected peptides using hybrid hydroxydimethylsilane derivatives. RSC Adv 2016. [DOI: 10.1039/c6ra06075g] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A straightforward way to dimerize unprotected peptide sequences is presented; it relies on a chemoselective condensation of hybrid peptides bearing a hydroxydimethylsilyl group at a chosen position to generate siloxane bonds upon freeze-drying.
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27
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Giorgio C, Russo S, Incerti M, Bugatti A, Vacondio F, Barocelli E, Mor M, Pala D, Hassan-Mohamed I, Gioiello A, Rusnati M, Lodola A, Tognolini M. Biochemical characterization of EphA2 antagonists with improved physico-chemical properties by cell-based assays and surface plasmon resonance analysis. Biochem Pharmacol 2015; 99:18-30. [PMID: 26462575 DOI: 10.1016/j.bcp.2015.10.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 10/06/2015] [Indexed: 12/28/2022]
Abstract
Amino acid conjugates of lithocholic acid (LCA) have been recently described as effective disruptors of the EphA2-ephrin-A1 interaction able to inhibit EphA2 phosphorylation in intact cells and thus able to block prometastatic responses such as cellular retraction and angiogenesis. However, these LCA-based compounds were significantly more potent at disrupting the EphA2-ephrin-A1 interaction than at blocking phenotype responses in cells, which might reflect an unclear mechanism of action or a metabolic issue responsible for a reduction of the compound concentration at the cell's surface. Through the synthesis of new compounds and their examination by a combination of cell-based assays and real-time interaction analysis by surface plasmon resonance, we showed at molecular level that l-tryptophan conjugates of lithocholic acid disrupt EphA2-ephrin-A1 interaction by targeting the EphA 2 receptor and that the presence of a polar group in position 3 of steroid scaffold is a key factor to increase the effective concentration of the compounds in cancer cell lines.
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Affiliation(s)
- Carmine Giorgio
- Dipartimento di Farmacia, Università degli Studi di Parma, Parma, Italy
| | - Simonetta Russo
- Dipartimento di Farmacia, Università degli Studi di Parma, Parma, Italy
| | - Matteo Incerti
- Dipartimento di Farmacia, Università degli Studi di Parma, Parma, Italy
| | - Antonella Bugatti
- Dipartimento di Medicina Molecolare Traslazionale, Università degli Studi di Brescia, Brescia, Italy
| | - Federica Vacondio
- Dipartimento di Farmacia, Università degli Studi di Parma, Parma, Italy
| | | | - Marco Mor
- Dipartimento di Farmacia, Università degli Studi di Parma, Parma, Italy
| | - Daniele Pala
- Dipartimento di Farmacia, Università degli Studi di Parma, Parma, Italy
| | | | - Antimo Gioiello
- Dipartimento di Scienze Farmaceutiche, Università degli Studi di Perugia, Perugia, Italy
| | - Marco Rusnati
- Dipartimento di Medicina Molecolare Traslazionale, Università degli Studi di Brescia, Brescia, Italy
| | - Alessio Lodola
- Dipartimento di Farmacia, Università degli Studi di Parma, Parma, Italy; Department of Applied Sciences, Faculty of Health and Life Sciences, Northumbria University, UK.
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28
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Callegari D, Pala D, Scalvini L, Tognolini M, Incerti M, Rivara S, Mor M, Lodola A. Comparative Analysis of Virtual Screening Approaches in the Search for Novel EphA2 Receptor Antagonists. Molecules 2015; 20:17132-51. [PMID: 26393553 PMCID: PMC6331951 DOI: 10.3390/molecules200917132] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 09/08/2015] [Accepted: 09/11/2015] [Indexed: 11/29/2022] Open
Abstract
The EphA2 receptor and its ephrin-A1 ligand form a key cell communication system, which has been found overexpressed in many cancer types and involved in tumor growth. Recent medicinal chemistry efforts have identified bile acid derivatives as low micromolar binders of the EphA2 receptor. However, these compounds suffer from poor physicochemical properties, hampering their use in vivo. The identification of compounds able to disrupt the EphA2-ephrin-A1 complex lacking the bile acid scaffold may lead to new pharmacological tools suitable for in vivo studies. To identify the most promising virtual screening (VS) protocol aimed at finding novel EphA2 antagonists, we investigated the ability of both ligand-based and structure-based approaches to retrieve known EphA2 antagonists from libraries of decoys with similar molecular properties. While ligand-based VSs were conducted using UniPR129 and ephrin-A1 ligand as reference structures, structure-based VSs were performed with Glide, using the X-ray structure of the EphA2 receptor/ephrin-A1 complex. A comparison of enrichment factors showed that ligand-based approaches outperformed the structure-based ones, suggesting ligand-based methods using the G-H loop of ephrin-A1 ligand as template as the most promising protocols to search for novel EphA2 antagonists.
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Affiliation(s)
- Donatella Callegari
- Dipartimento di Farmacia, Università degli Studi di Parma, Parma 43124, Italy.
| | - Daniele Pala
- Dipartimento di Farmacia, Università degli Studi di Parma, Parma 43124, Italy.
| | - Laura Scalvini
- Dipartimento di Farmacia, Università degli Studi di Parma, Parma 43124, Italy.
| | | | - Matteo Incerti
- Dipartimento di Farmacia, Università degli Studi di Parma, Parma 43124, Italy.
| | - Silvia Rivara
- Dipartimento di Farmacia, Università degli Studi di Parma, Parma 43124, Italy.
| | - Marco Mor
- Dipartimento di Farmacia, Università degli Studi di Parma, Parma 43124, Italy.
| | - Alessio Lodola
- Dipartimento di Farmacia, Università degli Studi di Parma, Parma 43124, Italy.
- Department of Applied Sciences, Northumbria University at Newcastle, Newcastle-Upon-Tyne, NE1 8ST, UK.
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29
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Park SH, Park S, Kim DY, Pyo A, Kimura RH, Sathirachinda A, Choy HE, Min JJ, Gambhir SS, Hong Y. Isolation and Characterization of a Monobody with a Fibronectin Domain III Scaffold That Specifically Binds EphA2. PLoS One 2015; 10:e0132976. [PMID: 26177208 PMCID: PMC4503726 DOI: 10.1371/journal.pone.0132976] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Accepted: 06/19/2015] [Indexed: 01/21/2023] Open
Abstract
Monobodies are binding scaffold proteins originating from a human fibronectin domain III (Fn3) scaffold that can be easily engineered with specificity and affinity. Human EphA2 (hEphA2) is an early detection marker protein for various tumors including lung, breast, and colon cancer. In this study, we isolated two hEphA2-specific monobodies (E1 and E10) by screening a yeast surface display library. They showed the same amino acid sequence except in the DE loop and had high affinity (~2 nM Kd) against hEphA2. E1 bound only hEphA2 and mEphA2, although it bound hEphA2 with an affinity 2-fold higher than that of mEphA2. However, E10 also bound the mEphA6 and mEphA8 homologs as well as hEphA2 and mEphA2. Thus, E1 but not E10 was highly specific for hEphA2. E1 specifically bound human cells and xenograft tumor tissues expressing hEphA on the cell surface. In vivo optical imaging showed strong targeting of Cy5.5-labeled E1 to mouse tumor tissue induced by PC3 cells, a human prostate cancer cell line that expresses a high level of hEphA2. In conclusion, the highly specific monobody E1 is useful as a hEphA2 probe candidate for in vivo diagnosis and therapy.
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Affiliation(s)
- Seung-Hwan Park
- Department of Nuclear Medicine, Chonnam National University Medical School, Gwangju, Republic of Korea
| | - Sukho Park
- Department of Microbiology, Chonnam National University Medical School, Gwangju, Republic of Korea
| | - Dong-Yeon Kim
- Department of Nuclear Medicine, Chonnam National University Medical School, Gwangju, Republic of Korea
| | - Ayoung Pyo
- Department of Nuclear Medicine, Chonnam National University Medical School, Gwangju, Republic of Korea
| | - Richard H. Kimura
- Molecular Imaging Program at Stanford, Department of Radiology, Bio-X Program, Stanford University, Palo Alto, CA, United States of America
| | - Ataya Sathirachinda
- Molecular Imaging Program at Stanford, Department of Radiology, Bio-X Program, Stanford University, Palo Alto, CA, United States of America
| | - Hyon E. Choy
- Department of Microbiology, Chonnam National University Medical School, Gwangju, Republic of Korea
| | - Jung-Joon Min
- Department of Nuclear Medicine, Chonnam National University Medical School, Gwangju, Republic of Korea
| | - Sanjiv Sam Gambhir
- Molecular Imaging Program at Stanford, Department of Radiology, Bio-X Program, Stanford University, Palo Alto, CA, United States of America
| | - Yeongjin Hong
- Department of Microbiology, Chonnam National University Medical School, Gwangju, Republic of Korea
- * E-mail:
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30
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Wu B, Wang S, De SK, Barile E, Quinn BA, Zharkikh I, Purves A, Stebbins JL, Oshima RG, Fisher PB, Pellecchia M. Design and Characterization of Novel EphA2 Agonists for Targeted Delivery of Chemotherapy to Cancer Cells. ACTA ACUST UNITED AC 2015; 22:876-887. [PMID: 26165155 DOI: 10.1016/j.chembiol.2015.06.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Revised: 05/22/2015] [Accepted: 06/10/2015] [Indexed: 10/23/2022]
Abstract
The development of novel, targeted delivery agents for anti-cancer therapies requires the design and optimization of potent and selective tumor-targeting agents that are stable and amenable to conjugation with chemotherapeutic drugs. While short peptides represent potentially an excellent platform for these purposes, they often get degraded and are eliminated too rapidly in vivo. In this study, we used a combination of nuclear magnetic resonance-guided structure-activity relationships along with biochemical and cellular studies to derive a novel tumor-homing agent, named 123B9, targeting the EphA2 tyrosine kinase receptor ligand-binding domain. Conjugating 123B9 to the chemotherapeutic drug paclitaxel (PTX) via a stable linker results in an agent that is significantly more effective than the unconjugated drug in both a pancreatic cancer xenograft model and a melanoma lung colonization and metastases model. Hence, 123B9 could represent a promising strategy for the development of novel targeted therapies for cancer.
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Affiliation(s)
- Bainan Wu
- Sanford-Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Si Wang
- Sanford-Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Surya K De
- Sanford-Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Elisa Barile
- Sanford-Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Bridget A Quinn
- Department of Human and Molecular Genetics, VCU Institute of Molecular Medicine and VCU Massey Cancer Center, Virginia Commonwealth University, School of Medicine, Richmond, VA 23298-0033, USA
| | - Irina Zharkikh
- Sanford-Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Angela Purves
- Sanford-Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - John L Stebbins
- Sanford-Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Robert G Oshima
- Sanford-Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Paul B Fisher
- Department of Human and Molecular Genetics, VCU Institute of Molecular Medicine and VCU Massey Cancer Center, Virginia Commonwealth University, School of Medicine, Richmond, VA 23298-0033, USA
| | - Maurizio Pellecchia
- Sanford-Burnham Medical Research Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA
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31
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Riedl SJ, Pasquale EB. Targeting the Eph System with Peptides and Peptide Conjugates. Curr Drug Targets 2015; 16:1031-47. [PMID: 26212263 PMCID: PMC4861043 DOI: 10.2174/1389450116666150727115934] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 02/02/2015] [Accepted: 07/20/2015] [Indexed: 01/06/2023]
Abstract
Eph receptor tyrosine kinases and ephrin ligands constitute an important cell communication system that controls development, tissue homeostasis and many pathological processes. Various Eph receptors/ephrins are present in essentially all cell types and their expression is often dysregulated by injury and disease. Thus, the 14 Eph receptors are attracting increasing attention as a major class of potential drug targets. In particular, agents that bind to the extracellular ephrin-binding pocket of these receptors show promise for medical applications. This pocket comprises a broad and shallow groove surrounded by several flexible loops, which makes peptides particularly suitable to target it with high affinity and selectivity. Accordingly, a number of peptides that bind to Eph receptors with micromolar affinity have been identified using phage display and other approaches. These peptides are generally antagonists that inhibit ephrin binding and Eph receptor/ ephrin signaling, but some are agonists mimicking ephrin-induced Eph receptor activation. Importantly, some of the peptides are exquisitely selective for single Eph receptors. Most identified peptides are linear, but recently the considerable advantages of cyclic scaffolds have been recognized, particularly in light of potential optimization towards drug leads. To date, peptide improvements have yielded derivatives with low nanomolar Eph receptor binding affinity, high resistance to plasma proteases and/or long in vivo half-life, exemplifying the merits of peptides for Eph receptor targeting. Besides their modulation of Eph receptor/ephrin function, peptides can also serve to deliver conjugated imaging and therapeutic agents or various types of nanoparticles to tumors and other diseased tissues presenting target Eph receptors.
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Affiliation(s)
| | - Elena B Pasquale
- Sanford Burnham Prebys Medical Discovery Institute, 10901 N. Torrey Pines Rd., La Jolla, CA 92037, USA.
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32
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Herington AC, Mertens-Walker I, Lisle JE, Maharaj M, Stephenson SA. Inhibiting Eph kinase activity may not be "Eph"ective for cancer treatment. Growth Factors 2014; 32:207-13. [PMID: 25413947 DOI: 10.3109/08977194.2014.985293] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Several Eph receptor tyrosine kinases (RTKs) are commonly over-expressed in epithelial and mesenchymal cancers and are recognized as promising therapeutic targets. Although normal interaction between Eph receptors and their ephrin ligands stimulates kinase activity and is generally tumor suppressive, significant Eph over-expression allows activation of ligand- and/or kinase-independent signaling pathways that promote oncogenesis. Single-agent kinase inhibitors are widely used to target RTK-driven tumors but acquired and de novo resistance to such agents is a major limitation to effective clinical use. Accumulating evidence suggests that Ephs can be inhibited by "leaky" or low-specificity kinase inhibitors targeted at other RTKs. Such off-target effects may therefore inadvertently promote ligand- and/or kinase-independent oncogenic Eph signaling, thereby providing a new mechanism by which resistance to the RTK inhibitors can emerge. We propose that combining specific, non-leaky kinase inhibitors with tumor-suppressive stimulators of Eph signaling may provide more effective treatment options for overcoming treatment-induced resistance and clinical failure.
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Affiliation(s)
- A C Herington
- Institute of Health and Biomedical Innovation, Queensland University of Technology , Queensland , Australia and
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33
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Abstract
The erythropoietin-producing hepatocellular carcinoma (Eph) receptor tyrosine kinase family plays important roles in developmental processes, adult tissue homeostasis, and various diseases. Interaction with Eph receptor-interacting protein (ephrin) ligands on the surface of neighboring cells triggers Eph receptor kinase-dependent signaling. The ephrins can also transmit signals, leading to bidirectional cell contact-dependent communication. Moreover, Eph receptors and ephrins can function independently of each other through interplay with other signaling systems. Given their involvement in many pathological conditions ranging from neurological disorders to cancer and viral infections, Eph receptors and ephrins are increasingly recognized as attractive therapeutic targets, and various strategies are being explored to modulate their expression and function. Eph receptor/ephrin upregulation in cancer cells, the angiogenic vasculature, and injured or diseased tissues also offer opportunities for Eph/ephrin-based targeted drug delivery and imaging. Thus, despite the challenges presented by the complex biology of the Eph receptor/ephrin system, exciting possibilities exist for therapies exploiting these molecules.
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Affiliation(s)
- Antonio Barquilla
- Cancer Center, Sanford-Burnham Medical Research Institute, La Jolla, California 92037; ,
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34
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Barile E, Wang S, Das SK, Noberini R, Dahl R, Stebbins JL, Pasquale EB, Fisher PB, Pellecchia M. Design, synthesis and bioevaluation of an EphA2 receptor-based targeted delivery system. ChemMedChem 2014; 9:1403-12. [PMID: 24677792 PMCID: PMC4082471 DOI: 10.1002/cmdc.201400067] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Indexed: 01/15/2023]
Abstract
Because of its overexpression in a range of solid tumors, the EphA2 receptor is a validated target for cancer therapeutics. We recently described a new targeted delivery system based on specific EphA2-targeting peptides conjugated with the chemotherapeutic agent paclitaxel. Here, we investigate the chemical determinants responsible for the stability and degradation of these agents in plasma. Introducing modifications in both the peptide and the linker between the peptide and paclitaxel resulted in drug conjugates that are both long-lived in rat plasma and that markedly decrease tumor size in a prostate cancer xenograft model compared with paclitaxel alone treatment. These studies identify critical rate-limiting degradation sites on the peptide-drug conjugates, enabling the design of agents with increased stability and efficacy. These results provide support for our central hypothesis that peptide-drug conjugates targeting EphA2 represent an innovative and potentially effective strategy to selectively deliver cytotoxic drugs to cancer cells.
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Affiliation(s)
- Elisa Barile
- Cancer Research Center, Sanford-Burnham Medical Research Institute, 10901 N. Torrey Pines Rd., La Jolla, CA 92037, USA
| | - Si Wang
- Cancer Research Center, Sanford-Burnham Medical Research Institute, 10901 N. Torrey Pines Rd., La Jolla, CA 92037, USA
| | - Swadesh K. Das
- Department of Human and Molecular Genetics, VCU Institute of Molecular Medicine, VCU Massey Cancer Center, Virginia Commonwealth University, School of Medicine, 1101 East Marshall Street, Sanger Hall Building, Room 11-015, Richmond, VA 23298-0033, USA
| | - Roberta Noberini
- Cancer Research Center, Sanford-Burnham Medical Research Institute, 10901 N. Torrey Pines Rd., La Jolla, CA 92037, USA
| | - Russell Dahl
- Rosalind Franklin University of Medicine and Science, College of Pharmacy, Chicago Medical School, Building: IPEC, Room: 2.80, 3333 Green Bay Road, North Chicago, Il 60064-3095
| | - John L. Stebbins
- Cancer Research Center, Sanford-Burnham Medical Research Institute, 10901 N. Torrey Pines Rd., La Jolla, CA 92037, USA
| | - Elena B. Pasquale
- Cancer Research Center, Sanford-Burnham Medical Research Institute, 10901 N. Torrey Pines Rd., La Jolla, CA 92037, USA
| | - Paul B. Fisher
- Department of Human and Molecular Genetics, VCU Institute of Molecular Medicine, VCU Massey Cancer Center, Virginia Commonwealth University, School of Medicine, 1101 East Marshall Street, Sanger Hall Building, Room 11-015, Richmond, VA 23298-0033, USA
| | - Maurizio Pellecchia
- Cancer Research Center, Sanford-Burnham Medical Research Institute, 10901 N. Torrey Pines Rd., La Jolla, CA 92037, USA
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35
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99mTc-labeled SWL specific peptide for targeting EphA2 receptor. Nucl Med Biol 2014; 41:450-6. [DOI: 10.1016/j.nucmedbio.2014.03.020] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Revised: 03/10/2014] [Accepted: 03/17/2014] [Indexed: 12/24/2022]
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Barton WA, Dalton AC, Seegar TCM, Himanen JP, Nikolov DB. Tie2 and Eph receptor tyrosine kinase activation and signaling. Cold Spring Harb Perspect Biol 2014; 6:cshperspect.a009142. [PMID: 24478383 DOI: 10.1101/cshperspect.a009142] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The Eph and Tie cell surface receptors mediate a variety of signaling events during development and in the adult organism. As other receptor tyrosine kinases, they are activated on binding of extracellular ligands and their catalytic activity is tightly regulated on multiple levels. The Eph and Tie receptors display some unique characteristics, including the requirement of ligand-induced receptor clustering for efficient signaling. Interestingly, both Ephs and Ties can mediate different, even opposite, biological effects depending on the specific ligand eliciting the response and on the cellular context. Here we discuss the structural features of these receptors, their interactions with various ligands, as well as functional implications for downstream signaling initiation. The Eph/ephrin structures are already well reviewed and we only provide a brief overview on the initial binding events. We go into more detail discussing the Tie-angiopoietin structures and recognition.
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Affiliation(s)
- William A Barton
- Department of Biochemistry and Molecular Biology, School of Medicine, Virginia Commonwealth University, Richmond, Virginia 23298
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Ma B, Nussinov R. Druggable orthosteric and allosteric hot spots to target protein-protein interactions. Curr Pharm Des 2014; 20:1293-301. [PMID: 23713780 PMCID: PMC6361532 DOI: 10.2174/13816128113199990073] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 05/21/2013] [Indexed: 11/22/2022]
Abstract
Drug designing targeting protein-protein interactions is challenging. Because structural elucidation and computational analysis have revealed the importance of hot spot residues in stabilizing these interactions, there have been on-going efforts to develop drugs which bind the hot spots and out-compete the native protein partners. The question arises as to what are the key 'druggable' properties of hot spots in protein-protein interactions and whether these mimic the general hot spot definition. Identification of orthosteric (at the protein- protein interaction site) and allosteric (elsewhere) druggable hot spots is expected to help in discovering compounds that can more effectively modulate protein-protein interactions. For example, are there any other significant features beyond their location in pockets in the interface? The interactions of protein-protein hot spots are coupled with conformational dynamics of protein complexes. Currently increasing efforts focus on the allosteric drug discovery. Allosteric drugs bind away from the native binding site and can modulate the native interactions. We propose that identification of allosteric hot spots could similarly help in more effective allosteric drug discovery. While detection of allosteric hot spots is challenging, targeting drugs to these residues has the potential of greatly increasing the hot spot and protein druggability.
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Affiliation(s)
| | - Ruth Nussinov
- Basic Science Program, Leidos Biomedical Research, Inc. Cancer and Inflammation Program, NCIFrederick, Frederick, MD 21702.
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Posthumadeboer J, Piersma SR, Pham TV, van Egmond PW, Knol JC, Cleton-Jansen AM, van Geer MA, van Beusechem VW, Kaspers GJL, van Royen BJ, Jiménez CR, Helder MN. Surface proteomic analysis of osteosarcoma identifies EPHA2 as receptor for targeted drug delivery. Br J Cancer 2013; 109:2142-54. [PMID: 24064975 PMCID: PMC3798973 DOI: 10.1038/bjc.2013.578] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 08/23/2013] [Accepted: 08/28/2013] [Indexed: 02/01/2023] Open
Abstract
BACKGROUND Osteosarcoma (OS) is the most common bone tumour in children and adolescents. Despite aggressive therapy regimens, treatment outcomes are unsatisfactory. Targeted delivery of drugs can provide higher effective doses at the site of the tumour, ultimately improving the efficacy of existing therapy. Identification of suitable receptors for drug targeting is an essential step in the design of targeted therapy for OS. METHODS We conducted a comparative analysis of the surface proteome of human OS cells and osteoblasts using cell surface biotinylation combined with nano-liquid chromatography - tandem mass spectrometry-based proteomics to identify surface proteins specifically upregulated on OS cells. This approach generated an extensive data set from which we selected a candidate to study for its suitability as receptor for targeted treatment delivery to OS. First, surface expression of the ephrin type-A receptor 2 (EPHA2) receptor was confirmed using FACS analysis. Ephrin type-A receptor 2 expression in human tumour tissue was tested using immunohistochemistry. Receptor targeting and internalisation studies were conducted to assess intracellular uptake of targeted modalities via EPHA2. Finally, tissue micro arrays containing cores of human OS tissue were stained using immunohistochemistry and EPHA2 staining was correlated to clinical outcome measures. RESULTS Using mass spectrometry, a total of 2841 proteins were identified of which 156 were surface proteins significantly upregulated on OS cells compared with human primary osteoblasts. Ephrin type-A receptor 2 was highly upregulated and the most abundant surface protein on OS cells. In addition, EPHA2 was expressed in a vast majority of human OS samples. Ephrin type-A receptor 2 effectively mediates internalisation of targeted adenoviral vectors into OS cells. Patients with EPHA2-positive tumours showed a trend toward inferior overall survival. CONCLUSION The results presented here suggest that the EPHA2 receptor can be considered an attractive candidate receptor for targeted delivery of therapeutics to OS.
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Affiliation(s)
- J Posthumadeboer
- Department of Orthopaedic Surgery, VU University Medical Center, PO Box 7057, 1007 MB Amsterdam, The Netherlands
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Duggineni S, Mitra S, Lamberto I, Han X, Xu Y, An J, Pasquale EB, Huang Z. Design and Synthesis of Potent Bivalent Peptide Agonists Targeting the EphA2 Receptor. ACS Med Chem Lett 2013; 4. [PMID: 24167659 DOI: 10.1021/ml3004523] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Designing potent and selective peptides and small molecules that target Eph receptor tyrosine kinases remains a challenge and new strategies are needed for developing novel and potent ligands for these receptors. In this study, we performed a structure-activity relationship study of a previously identified 12 amino acid-long peptide, SWL, by alanine scanning to identify residues important for receptor binding. To further enhance and optimize the receptor binding affinity of the SWL peptide, we applied the concept of bivalent ligand design to synthesize several SWL-derived dimeric peptides as novel ligands capable of binding simultaneously to two EphA2 receptor molecules. The dimeric peptides possess higher receptor binding affinity than the original monomeric SWL peptide, consistent with bivalent binding. The most potent dimeric peptide, a SWL dimer with a 6 carbon linker, has about 13 fold increased potency compared to SWL. Furthermore, similar to SWL, the dimeric peptide is an agonist and can promote EphA2 tyrosine phosphorylation (activation) in cultured cells.
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Affiliation(s)
- Srinivas Duggineni
- SUNY Upstate Cancer Research Institute,
Department of Pharmacology, State University of New York, Syracuse,
New York 13210, United States
| | - Sayantan Mitra
- Sanford-Burnham Medical Research Institute,
La Jolla, California 92037, United States
| | - Ilaria Lamberto
- Sanford-Burnham Medical Research Institute,
La Jolla, California 92037, United States
| | - Xiaofeng Han
- SUNY Upstate Cancer Research Institute,
Department of Pharmacology, State University of New York, Syracuse,
New York 13210, United States
| | - Yan Xu
- SUNY Upstate Cancer Research Institute,
Department of Pharmacology, State University of New York, Syracuse,
New York 13210, United States
| | - Jing An
- SUNY Upstate Cancer Research Institute,
Department of Pharmacology, State University of New York, Syracuse,
New York 13210, United States
| | - Elena B. Pasquale
- Sanford-Burnham Medical Research Institute,
La Jolla, California 92037, United States
- Department of Pathology, University
of California, San Diego, California 92093, United States
| | - Ziwei Huang
- SUNY Upstate Cancer Research Institute,
Department of Pharmacology, State University of New York, Syracuse,
New York 13210, United States
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40
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Funk SD, Orr AW. Ephs and ephrins resurface in inflammation, immunity, and atherosclerosis. Pharmacol Res 2013; 67:42-52. [DOI: 10.1016/j.phrs.2012.10.008] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Revised: 10/04/2012] [Accepted: 10/10/2012] [Indexed: 01/13/2023]
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41
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Wang S, Noberini R, Stebbins JL, Das S, Zhang Z, Wu B, Mitra S, Billet S, Fernandez A, Bhowmick NA, Kitada S, Pasquale EB, Fisher PB, Pellecchia M. Targeted delivery of paclitaxel to EphA2-expressing cancer cells. Clin Cancer Res 2012; 19:128-37. [PMID: 23155185 DOI: 10.1158/1078-0432.ccr-12-2654] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
PURPOSE YSA is an EphA2-targeting peptide that effectively delivers anticancer agents to prostate cancer tumors. Here, we report on how we increased the drug-like properties of this delivery system. EXPERIMENTAL DESIGN By introducing non-natural amino acids, we have designed two new EphA2 targeting peptides: YNH, where norleucine and homoserine replace the two methionine residues of YSA, and dYNH, where a D-tyrosine replaces the L-tyrosine at the first position of the YNH peptide. We describe the details of the synthesis of YNH and dYNH paclitaxel conjugates (YNH-PTX and dYNH-PTX) and their characterization in cells and in vivo. RESULTS dYNH-PTX showed improved stability in mouse serum and significantly reduced tumor size in a prostate cancer xenograft model and also reduced tumor vasculature in a syngeneic orthotopic allograft mouse model of renal cancer compared with vehicle or paclitaxel treatments. CONCLUSION This study reveals that targeting EphA2 with dYNH drug conjugates could represent an effective way to deliver anticancer agents to a variety of tumor types.
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Affiliation(s)
- Si Wang
- Cancer Research Center, Sanford-Burnham Medical Research Institute, La Jolla, CA 90237, USA
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42
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Zozulya SA, Udovichenko IP. [Eph family receptors as therapeutic targets]. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2012; 38:267-79. [PMID: 22997698 DOI: 10.1134/s106816201203017x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Anti-angiogenic therapy is currently a commonly accepted and rapidly developing approach in oncology and other pathologies linked to aberrant neovascularization. Discovery and validation of additional molecular targets in angiogenesis is needed due to the limitations of the existing clinical therapeutics inhibiting activity of vascular endothelial growth factor (VEGF) and its receptors. A brief review of normal and pathological biological functions of the Eph family of receptor tyrosine kinases and their ephrin ligands is presented, and the approaches to developing therapeutics with anti- and pro-angiogenic and anti-tumor activity based on selective molecular modulation of Eph-ephrin signaling pairs are discussed. Functional roles of Eph-kinases and ephrins in such mechanisms of cancerogenesis as cell proliferation and invasion are also addressed.
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43
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Rodger J, Salvatore L, Migani P. Should I stay or should I go? Ephs and ephrins in neuronal migration. Neurosignals 2012; 20:190-201. [PMID: 22456188 DOI: 10.1159/000333784] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
In neuroscience, Ephs and ephrins are perhaps best known for their role in axon guidance. It was first shown in the visual system that graded expression of these proteins is instrumental in providing molecular coordinates that define topographic maps, particularly in the visual system, but also in the auditory, vomeronasal and somatosensory systems as well as in the hippocampus, cerebellum and other structures. Perhaps unsurprisingly, the role of these proteins in regulating cell-cell interactions also has an impact on cell mobility, with evidence that Eph-ephrin interactions segregate cell populations based on contact-mediated attraction or repulsion. Consistent with these studies, evidence has accumulated that Ephs and ephrins play important roles in the migration of specific cell populations in the developing and adult brain. This review focusses on two examples of neuronal migration that require Eph/ephrin signalling - radial and tangential migration of neurons in cortical development and the migration of newly generated neurons along the rostral migratory stream to the olfactory bulb in the adult brain. We discuss the challenge involved in understanding how cells determine whether they respond to signals by migration or axon guidance.
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Affiliation(s)
- Jennifer Rodger
- Experimental and Regenerative Neurosciences, School of Animal Biology M317, University of Western Australia, Crawley, WA, Australia
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44
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Wang S, Placzek WJ, Stebbins JL, Mitra S, Noberini R, Koolpe M, Zhang Z, Dahl R, Pasquale EB, Pellecchia M. Novel targeted system to deliver chemotherapeutic drugs to EphA2-expressing cancer cells. J Med Chem 2012; 55:2427-36. [PMID: 22329578 DOI: 10.1021/jm201743s] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The efficacy of anticancer drugs is often limited by their systemic toxicities and adverse side effects. We report that the EphA2 receptor is overexpressed preferentially in several human cancer cell lines compared to normal tissues and that an EphA2 targeting peptide (YSAYPDSVPMMS) can be effective in delivering anticancer agents to such tumors. Hence, we report on the synthesis and characterizations of a novel EphA2-targeting agent conjugated with the chemotherapeutic drug paclitaxel. We found that the peptide-drug conjugate is dramatically more effective than paclitaxel alone at inhibiting tumor growth in a prostate cancer xenograft model, delivering significantly higher levels of drug to the tumor site. We believe these studies open the way to the development of a new class of therapeutic compounds that exploit the EphA2 receptor for drug delivery to cancer cells.
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Affiliation(s)
- Si Wang
- Cancer Research Center, Sanford-Burnham Medical Research Institute, 10901 N. Torrey Pines Road, La Jolla, California 92037, USA
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45
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Noberini R, Mitra S, Salvucci O, Valencia F, Duggineni S, Prigozhina N, Wei K, Tosato G, Huang Z, Pasquale EB. PEGylation potentiates the effectiveness of an antagonistic peptide that targets the EphB4 receptor with nanomolar affinity. PLoS One 2011; 6:e28611. [PMID: 22194865 PMCID: PMC3237458 DOI: 10.1371/journal.pone.0028611] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Accepted: 11/11/2011] [Indexed: 01/12/2023] Open
Abstract
The EphB4 receptor tyrosine kinase together with its preferred ligand, ephrin-B2, regulates a variety of physiological and pathological processes, including tumor progression, pathological forms of angiogenesis, cardiomyocyte differentiation and bone remodeling. We previously reported the identification of TNYL-RAW, a 15 amino acid-long peptide that binds to the ephrin-binding pocked of EphB4 with low nanomolar affinity and inhibits ephrin-B2 binding. Although ephrin-B2 interacts promiscuously with all the EphB receptors, the TNYL-RAW peptide is remarkably selective and only binds to EphB4. Therefore, this peptide is a useful tool for studying the biological functions of EphB4 and for imaging EphB4-expressing tumors. Furthermore, TNYL-RAW could be useful for treating pathologies involving EphB4-ephrin-B2 interaction. However, the peptide has a very short half-life in cell culture and in the mouse blood circulation due to proteolytic degradation and clearance by the kidneys and reticuloendothelial system. To overcome these limitations, we have modified TNYL-RAW by fusion with the Fc portion of human IgG1, complexation with streptavidin or covalent coupling to a 40 KDa branched polyethylene glycol (PEG) polymer. These modified forms of TNYL-RAW all have greatly increased stability in cell culture, while retaining high binding affinity for EphB4. Furthermore, PEGylation most effectively increases peptide half-life in vivo. Consistent with increased stability, submicromolar concentrations of PEGylated TNYL-RAW effectively impair EphB4 activation by ephrin-B2 in cultured B16 melanoma cells as well as capillary-like tube formation and capillary sprouting in co-cultures of endothelial and epicardial mesothelial cells. Therefore, PEGylated TNYL-RAW may be useful for inhibiting pathological forms of angiogenesis through a novel mechanism involving disruption of EphB4-ephrin-B2 interactions between endothelial cells and supporting perivascular mesenchymal cells. Furthermore, the PEGylated peptide is suitable for other cell culture and in vivo applications requiring prolonged EphB4 receptor targeting.
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Affiliation(s)
- Roberta Noberini
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Sayantan Mitra
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Ombretta Salvucci
- Laboratory of Cellular Oncology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Fatima Valencia
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Srinivas Duggineni
- Department of Pharmacology, State University of New York Upstate Cancer Research Institute, State University of New York, Syracuse, New York, United States of America
| | - Natalie Prigozhina
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
- Biology Department, University of San Diego, San Diego, California, United States of America
| | - Ke Wei
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Giovanna Tosato
- Laboratory of Cellular Oncology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Ziwei Huang
- Department of Pharmacology, State University of New York Upstate Cancer Research Institute, State University of New York, Syracuse, New York, United States of America
| | - Elena B. Pasquale
- Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
- Department of Pathology, University of California San Diego, San Diego, California, United States of America
- * E-mail:
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46
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Tian W, Xu Y, Han X, Duggineni S, Han X, Huang Z, An J. Development of a Novel Fluorescence Polarization–Based Assay for Studying the β-Catenin/Tcf4 Interaction. ACTA ACUST UNITED AC 2011; 17:530-4. [DOI: 10.1177/1087057111429745] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Aberrant activation of the Wnt/β-catenin signaling pathway is associated with a wide range of human cancers. The interaction of β-catenin with T cell factor (Tcf) is a key step in activation of proliferative genes in this pathway. Interruption of this interaction would be a valuable strategy as a tumor therapy. In this study, we developed a novel fluorescein isothiocyanate (FITC)–labeled Tcf4-derived probe for identification of inhibitors of the β-catenin/Tcf4 interaction using a fluorescence polarization assay. This assay shows high potential for use in high-throughput screening for the discovery of inhibitors of the β-catenin/Tcf4 interaction.
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Affiliation(s)
- Wang Tian
- Department of Pharmacology, State University of New York, Upstate Medical University, Syracuse, NY, USA
- Upstate Cancer Research Institute, State University of New York, Upstate Medical University, Syracuse, NY, USA
| | - Yan Xu
- Department of Pharmacology, State University of New York, Upstate Medical University, Syracuse, NY, USA
- Upstate Cancer Research Institute, State University of New York, Upstate Medical University, Syracuse, NY, USA
| | - Xiaofeng Han
- Department of Pharmacology, State University of New York, Upstate Medical University, Syracuse, NY, USA
- Upstate Cancer Research Institute, State University of New York, Upstate Medical University, Syracuse, NY, USA
| | - Srinivas Duggineni
- Department of Pharmacology, State University of New York, Upstate Medical University, Syracuse, NY, USA
- Upstate Cancer Research Institute, State University of New York, Upstate Medical University, Syracuse, NY, USA
| | - Xiaobing Han
- Department of Pharmacology, State University of New York, Upstate Medical University, Syracuse, NY, USA
- Upstate Cancer Research Institute, State University of New York, Upstate Medical University, Syracuse, NY, USA
| | - Ziwei Huang
- Department of Pharmacology, State University of New York, Upstate Medical University, Syracuse, NY, USA
- Upstate Cancer Research Institute, State University of New York, Upstate Medical University, Syracuse, NY, USA
| | - Jing An
- Department of Pharmacology, State University of New York, Upstate Medical University, Syracuse, NY, USA
- Upstate Cancer Research Institute, State University of New York, Upstate Medical University, Syracuse, NY, USA
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Noberini R, Lamberto I, Pasquale EB. Targeting Eph receptors with peptides and small molecules: progress and challenges. Semin Cell Dev Biol 2011; 23:51-7. [PMID: 22044885 DOI: 10.1016/j.semcdb.2011.10.023] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Accepted: 10/17/2011] [Indexed: 11/18/2022]
Abstract
The Eph receptors are a large family of receptor tyrosine kinases. Their kinase activity and downstream signaling ability are stimulated by the binding of cell surface-associated ligands, the ephrins. The ensuing signals are bidirectional because the ephrins can also transduce signals (known as reverse signals) following their interaction with Eph receptors. The ephrin-binding pocket in the extracellular N-terminal domain of the Eph receptors and the ATP-binding pocket in the intracellular kinase domain represent potential binding sites for peptides and small molecules. Indeed, a number of peptides and chemical compounds that target Eph receptors and inhibit ephrin binding or kinase activity have been identified. These molecules show promise as probes to study Eph receptor/ephrin biology, as lead compounds for drug development, and as targeting agents to deliver drugs or imaging agents to tumors. Current challenges are to find (1) small molecules that inhibit Eph receptor-ephrin interactions with high binding affinity and good lead-like properties and (2) selective kinase inhibitors that preferentially target the Eph receptor family or subsets of Eph receptors. Strategies that could also be explored include targeting additional Eph receptor interfaces and the ephrin ligands.
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Affiliation(s)
- Roberta Noberini
- Sanford-Burnham Medical Research Institute, 10901 N. Torrey Pines Rd., La Jolla, CA 92037, USA
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48
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Himanen JP. Ectodomain structures of Eph receptors. Semin Cell Dev Biol 2011; 23:35-42. [PMID: 22044883 DOI: 10.1016/j.semcdb.2011.10.025] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Accepted: 10/17/2011] [Indexed: 11/25/2022]
Abstract
Eph receptors, the largest subfamily of receptor tyrosine kinases (RTKs), and their ephrin ligands are important mediators of cell-cell communication that regulate axon guidance, long-term potentiation, and stem cell development, among others. By now, many Eph receptors and ephrins have also been found to play important roles in the progression of cancer. Since both the receptor and the ligand are membrane-bound, their interaction leads to the multimerization of both molecules to distinct clusters within their respective plasma membranes, resulting in the formation of discrete signaling centers. In addition, and unique to Eph receptors and ephrins, their interaction initiates bi-directional signaling cascades where information is transduced in the direction of both the receptor- and the ligand-bearing cells. The Ephs and the ephrins are divided into two subclasses, A and B, based on their affinities for each other and on sequence conservation. Crystal structures and other biophysical studies have indicated that isolated extracellular Eph and ephrin domains initially form high-affinity heterodimers around a hydrophobic loop of the ligand that is buried in a hydrophobic pocket on the surface of the receptor. The dimers can then further arrange by weaker interactions into higher-order Eph/ephrin clusters observed in vivo at the sites of cell-cell contact. Although the hetero-dimerization is a universal way to initiate signaling, other extracellular domains of Ephs are involved in the formation of higher-order clusters. The structures also show important differences defining the unique partner preferences of the two ligand and receptor subclasses, namely, how subclass specificity is determined both by individual interacting residues and by the precise architectural arrangement of ligands and receptors within the complexes.
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Affiliation(s)
- Juha P Himanen
- Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA.
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Noberini R, De SK, Zhang Z, Wu B, Raveendra-Panickar D, Chen V, Vazquez J, Qin H, Song J, Cosford NDP, Pellecchia M, Pasquale EB. A disalicylic acid-furanyl derivative inhibits ephrin binding to a subset of Eph receptors. Chem Biol Drug Des 2011; 78:667-78. [PMID: 21791013 DOI: 10.1111/j.1747-0285.2011.01199.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Eph receptor tyrosine kinases and ephrin ligands control many physiological and pathological processes, and molecules interfering with their interaction are useful probes to elucidate their complex biological functions. Moreover, targeting Eph receptors might enable new strategies to inhibit cancer progression and pathological angiogenesis as well as promote nerve regeneration. Because our previous work suggested the importance of the salicylic acid group in antagonistic small molecules targeting Eph receptors, we screened a series of salicylic acid derivatives to identify novel Eph receptor antagonists. This identified a disalicylic acid-furanyl derivative that inhibits ephrin-A5 binding to EphA4 with an IC(50) of 3 μm in ELISAs. This compound, which appears to bind to the ephrin-binding pocket of EphA4, also targets several other Eph receptors. Furthermore, it inhibits EphA2 and EphA4 tyrosine phosphorylation in cells stimulated with ephrin while not affecting phosphorylation of EphB2, which is not a target receptor. In endothelial cells, the disalicylic acid-furanyl derivative inhibits EphA2 phosphorylation in response to TNFα and capillary-like tube formation on Matrigel, two effects that depend on EphA2 interaction with endogenous ephrin-A1. These findings suggest that salicylic acid derivatives could be used as starting points to design new small molecule antagonists of Eph receptors.
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Affiliation(s)
- Roberta Noberini
- Sanford-Burnham Medical Research Institute, La Jolla, CA 92037, USA.
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Wang P, Wang L, Ding ZL, Zeng KF, Jin HL, Zhu H, Shi RH. Expression of EphA2 under hypoxia promotes vasculogenic mimicry in esophageal squamous cell carcinoma cells. Shijie Huaren Xiaohua Zazhi 2011; 19:996-1000. [DOI: 10.11569/wcjd.v19.i10.996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the effect of expression of Eph receptor tyrosine kinase A2 (EphA2) under normoxia and hypoxia on vasculogenic mimicry in esophageal squamous cell carcinoma cells.
METHODS: The expression of EphA2 mRNA and protein was measured by RT-PCR and Western blot in two esophageal cancer cell lines Eca109 and TE13 incubated under normoxia and hypoxia. Eca109 and TE13 cells were then transfected with a plasmid harboring small interfering RNA (siRNA) targeting EphA2. Tubular network formation in Eca109 and TE13 cells before and after siRNA transfection was analyzed using the three-dimensional Matrigel culture system under normoxia and hypoxia.
RESULTS: The expression of EphA2 in Eca109 and TE13 cells was obviously enhanced under hypoxia (P < 0.05). The numbers of tubular networks remarkably increased in both Eca109 and TE13 cells under hypoxia (P < 0.05). Although the numbers of tubules obviously increased under both hypoxia and normoxia, the increase was more significant under hypoxia (P < 0.01). Tubule-forming ability of cells transfected with a plasmid harboring small interfering RNA targeting EphA2 was significantly reduced.
CONCLUSION: Enhanced expression of EphA2 under hypoxia can increase the numbers of tubular networks in esophageal squamous cell carcinoma cells. Tubule-forming ability of cells transfected with a plasmid harboring siRNA targeting EphA2 was significantly inhibited. EphA2 may play an essential role in the formation of vasculogenic mimicry under hypoxia.
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