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Lins J, Miloslavina YA, Carrara SC, Rösler L, Hofmann S, Herr K, Theiß F, Wienands L, Avrutina O, Kolmar H, Buntkowsky G. Parahydrogen-induced polarization allows 2000-fold signal enhancement in biologically active derivatives of the peptide-based drug octreotide. Sci Rep 2023; 13:6388. [PMID: 37076553 PMCID: PMC10115808 DOI: 10.1038/s41598-023-33577-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 04/14/2023] [Indexed: 04/21/2023] Open
Abstract
Octreotide, a somatostatin analogue, has shown its efficacy for the diagnostics and treatment of various types of cancer, i.e., in octreotide scan, as radio-marker after labelling with a radiopharmaceutical. To avoid toxicity of radio-labeling, octreotide-based assays can be implemented into magnetic resonance techniques, such as MRI and NMR. Here we used a Parahydrogen-Induced Polarization (PHIP) approach as a cheap, fast and straightforward method. Introduction of L-propargyl tyrosine as a PHIP marker at different positions of octreotide by manual Solid-Phase Peptide Synthesis (SPPS) led to up to 2000-fold proton signal enhancement (SE). Cell binding studies confirmed that all octreotide variants retained strong binding affinity to the surface of human-derived cancer cells expressing somatostatin receptor 2. The hydrogenation reactions were successfully performed in methanol and under physiologically compatible mixtures of water with methanol or ethanol. The presented results open up new application areas of biochemical and pharmacological studies with octreotide.
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Affiliation(s)
- Jonas Lins
- Eduard-Zintl-Institute for Inorganic and Physical Chemistry, Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287, Darmstadt, Germany
| | - Yuliya A Miloslavina
- Eduard-Zintl-Institute for Inorganic and Physical Chemistry, Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287, Darmstadt, Germany
| | - Stefania C Carrara
- Clemens-Schöpf-Institute for Organic Chemistry and Biochemistry, Technische Universität Darmstadt, Alarich-Weiss-Straße 4, 64287, Darmstadt, Germany
| | - Lorenz Rösler
- Eduard-Zintl-Institute for Inorganic and Physical Chemistry, Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287, Darmstadt, Germany
| | - Sarah Hofmann
- Clemens-Schöpf-Institute for Organic Chemistry and Biochemistry, Technische Universität Darmstadt, Alarich-Weiss-Straße 4, 64287, Darmstadt, Germany
| | - Kevin Herr
- Eduard-Zintl-Institute for Inorganic and Physical Chemistry, Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287, Darmstadt, Germany
| | - Franziska Theiß
- Eduard-Zintl-Institute for Inorganic and Physical Chemistry, Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287, Darmstadt, Germany
| | - Laura Wienands
- Eduard-Zintl-Institute for Inorganic and Physical Chemistry, Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287, Darmstadt, Germany
| | - Olga Avrutina
- Clemens-Schöpf-Institute for Organic Chemistry and Biochemistry, Technische Universität Darmstadt, Alarich-Weiss-Straße 4, 64287, Darmstadt, Germany
| | - Harald Kolmar
- Clemens-Schöpf-Institute for Organic Chemistry and Biochemistry, Technische Universität Darmstadt, Alarich-Weiss-Straße 4, 64287, Darmstadt, Germany.
| | - Gerd Buntkowsky
- Eduard-Zintl-Institute for Inorganic and Physical Chemistry, Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287, Darmstadt, Germany.
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Panait ME, Chilug L, Negoita V, Busca A, Manda G, Niculae D, Dumitru M, Gruia MI. Biological Effects Induced by 68Ga-Conjugated Peptides in Human and Rodent Tumor Cell Lines. Int J Pept Res Ther 2019. [DOI: 10.1007/s10989-018-9745-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Hernandez Vargas S, Kossatz S, Voss J, Ghosh SC, Tran Cao HS, Simien J, Reiner T, Dhingra S, Fisher WE, Azhdarinia A. Specific Targeting of Somatostatin Receptor Subtype-2 for Fluorescence-Guided Surgery. Clin Cancer Res 2019; 25:4332-4342. [PMID: 31015345 DOI: 10.1158/1078-0432.ccr-18-3312] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 03/11/2019] [Accepted: 04/18/2019] [Indexed: 12/24/2022]
Abstract
PURPOSE Clinically available intraoperative imaging tools to assist surgeons in identifying occult lesions are limited and partially responsible for the high rate of disease recurrence in patients with neuroendocrine tumors (NET). Using the established clinical efficacy of radiolabeled somatostatin analogs as a model, we demonstrate the ability of a fluorescent somatostatin analog to selectively target tumors that overexpress somatostatin receptor subtype-2 (SSTR2) and demonstrate utility for fluorescence-guided surgery (FGS). EXPERIMENTAL DESIGN A multimodality chelator (MMC) was used as a "radioactive linker" to synthesize the fluorescently labeled somatostatin analog, 67/68Ga-MMC(IR800)-TOC. In vivo studies were performed to determine the pharmacokinetic profile, optimal imaging time point, and specificity for SSTR2-expressing tissues. Meso- and microscopic imaging of resected tissues and frozen sections were also performed to further assess specific binding, and binding to human NETs was examined using surgical biospecimens from patients with pancreatic NETs. RESULTS Direct labeling with 67Ga/68Ga provided quantitative biodistribution analysis that was in agreement with fluorescence data. Receptor-mediated uptake was observed in vivo and ex vivo at the macro-, meso-, and microscopic scales. Surgical biospecimens from patients with pancreatic NETs also displayed receptor-specific agent binding, allowing clear delineation of tumor boundaries that matched pathology findings. CONCLUSIONS The radioactive utility of the MMC allowed us to validate the binding properties of a novel FGS agent that could have a broad impact on cancer outcomes by equipping surgeons with real-time intraoperative imaging capabilities.
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Affiliation(s)
- Servando Hernandez Vargas
- The Brown Foundation Institute of Molecular Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, Texas
| | - Susanne Kossatz
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Julie Voss
- The Brown Foundation Institute of Molecular Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, Texas
| | - Sukhen C Ghosh
- The Brown Foundation Institute of Molecular Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, Texas
| | - Hop S Tran Cao
- Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas
| | - Jo Simien
- The Brown Foundation Institute of Molecular Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, Texas
| | - Thomas Reiner
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York.,Department of Radiology, Weill Cornell Medical College, New York, New York
| | - Sadhna Dhingra
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, Texas
| | - William E Fisher
- Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas
| | - Ali Azhdarinia
- The Brown Foundation Institute of Molecular Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, Texas.
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Lindner S, Fiedler L, Wängler B, Bartenstein P, Schirrmacher R, Wängler C. Design, synthesis and in vitro evaluation of heterobivalent peptidic radioligands targeting both GRP- and VPAC1-Receptors concomitantly overexpressed on various malignancies – Is the concept feasible? Eur J Med Chem 2018; 155:84-95. [DOI: 10.1016/j.ejmech.2018.05.047] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 05/23/2018] [Accepted: 05/28/2018] [Indexed: 02/06/2023]
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Purohit NK, Shah RG, Adant S, Hoepfner M, Shah GM, Beauregard JM. Potentiation of 177Lu-octreotate peptide receptor radionuclide therapy of human neuroendocrine tumor cells by PARP inhibitor. Oncotarget 2018; 9:24693-24706. [PMID: 29872498 PMCID: PMC5973847 DOI: 10.18632/oncotarget.25266] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 04/06/2018] [Indexed: 01/02/2023] Open
Abstract
For patients with inoperable neuroendocrine tumors (NETs) expressing somatostatin receptors, peptide receptor radionuclide therapy (PRRT) with 177Lu-[DOTA0-Tyr3]-octreotate (177Lu-octreotate) is one of the most promising targeted therapeutic options but it rarely achieves cure. Therefore, different approaches are being tested to increase the efficacy of 177Lu-octreotate PRRT in NET patients. Using the gastroenteropancreatic BON-1 and the bronchopulmonary NCI-H727 as NET cell models, here we report that pharmacological inhibitors of DNA repair-associated enzyme poly(ADP-ribose) polymerase-1 (PARPi) potentiate the cytotoxic effect of 177Lu-octreotate on 2D monolayer and 3D spheroid models of these two types of NET cells. PARPi mediates this effect by enhancing 177Lu-octreotate-induced cell cycle arrest and cell death. Thus, the use of PARPi may offer a novel option for improving the therapeutic efficacy of 177Lu-octreotate PRRT of NETs.
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Affiliation(s)
- Nupur K. Purohit
- Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Quebec City, Canada
- Cancer Research Center, Université Laval, Quebec City, Canada
- Neurosciences and Oncology Branches of CHU de Québec, Université Laval Research Center, Quebec City, Canada
| | - Rashmi G. Shah
- Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Quebec City, Canada
- Cancer Research Center, Université Laval, Quebec City, Canada
- Neurosciences and Oncology Branches of CHU de Québec, Université Laval Research Center, Quebec City, Canada
| | - Samuel Adant
- Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Quebec City, Canada
- Cancer Research Center, Université Laval, Quebec City, Canada
- Neurosciences and Oncology Branches of CHU de Québec, Université Laval Research Center, Quebec City, Canada
- Department of Radiology and Nuclear Medicine, Université Laval, Quebec City, Canada
- Oncology Branch of CHU de Québec, Université Laval Research Center, Quebec City, Canada
| | - Michael Hoepfner
- Institute of Physiology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Girish M. Shah
- Department of Molecular Biology, Medical Biochemistry and Pathology, Université Laval, Quebec City, Canada
- Cancer Research Center, Université Laval, Quebec City, Canada
- Neurosciences and Oncology Branches of CHU de Québec, Université Laval Research Center, Quebec City, Canada
| | - Jean-Mathieu Beauregard
- Cancer Research Center, Université Laval, Quebec City, Canada
- Department of Radiology and Nuclear Medicine, Université Laval, Quebec City, Canada
- Oncology Branch of CHU de Québec, Université Laval Research Center, Quebec City, Canada
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Moreno P, Mantey SA, Lee SH, Ramos-Álvarez I, Moody TW, Jensen RT. A possible new target in lung-cancer cells: The orphan receptor, bombesin receptor subtype-3. Peptides 2018; 101:213-226. [PMID: 29410320 PMCID: PMC6159918 DOI: 10.1016/j.peptides.2018.01.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 01/27/2018] [Accepted: 01/31/2018] [Indexed: 12/11/2022]
Abstract
Human bombesin receptors, GRPR and NMBR, are two of the most frequently overexpressed G-protein-coupled-receptors by lung-cancers. Recently, GRPR/NMBR are receiving considerable attention because they act as growth factor receptors often in an autocrine manner in different lung-cancers, affect tumor angiogenesis, their inhibition increases the cytotoxic potency of tyrosine-kinase inhibitors reducing lung-cancer cellular resistance/survival and their overexpression can be used for sensitive tumor localization as well as to target cytotoxic agents to the cancer. The orphan BRS-3-receptor, because of homology is classified as a bombesin receptor but has received little attention, despite the fact that it is also reported in a number of studies in lung-cancer cells and has growth effects in these cells. To address its potential importance, in this study, we examined the frequency/relative quantitative expression of human BRS-3 compared to GRPR/NMBR and the effects of its activation on cell-signaling/growth in 13 different human lung-cancer cell-lines. Our results showed that BRS-3 receptor is expressed in 92% of the cell-lines and that it is functional in these cells, because its activation stimulates phospholipase-C with breakdown of phosphoinositides and changes in cytosolic calcium, stimulates ERK/MAPK and stimulates cell growth by EGFR transactivation in some, but not all, the lung-cancer cell-lines. These results suggest that human BRS-3, similar to GRPR/NMBR, is frequently ectopically-expressed by lung-cancer cells in which, it is functional, affecting cell signaling/growth. These results suggest that similar to GRPR/NMBR, BRS-3 should receive increased attention as possible approach for the development of novel treatments and/or diagnosis in lung-cancer.
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Affiliation(s)
- Paola Moreno
- Department of Health and Human Services, Digestive Diseases Branch, NIDDK, United States
| | - Samuel A Mantey
- Department of Health and Human Services, Digestive Diseases Branch, NIDDK, United States
| | - Suk H Lee
- Department of Health and Human Services, Digestive Diseases Branch, NIDDK, United States
| | - Irene Ramos-Álvarez
- Department of Health and Human Services, Digestive Diseases Branch, NIDDK, United States
| | - Terry W Moody
- Center for Cancer Research, Office of the Director, NCI, National Institutes of Health, Bethesda, MD 20892-1804, United States
| | - Robert T Jensen
- Department of Health and Human Services, Digestive Diseases Branch, NIDDK, United States.
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Khan M, Huang T, Lin CY, Wu J, Fan BM, Bian ZX. Exploiting cancer's phenotypic guise against itself: targeting ectopically expressed peptide G-protein coupled receptors for lung cancer therapy. Oncotarget 2017; 8:104615-104637. [PMID: 29262666 PMCID: PMC5732832 DOI: 10.18632/oncotarget.18403] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 05/23/2017] [Indexed: 02/07/2023] Open
Abstract
Lung cancer, claiming millions of lives annually, has the highest mortality rate worldwide. This advocates the development of novel cancer therapies that are highly toxic for cancer cells but negligibly toxic for healthy cells. One of the effective treatments is targeting overexpressed surface receptors of cancer cells with receptor-specific drugs. The receptors-in-focus in the current review are the G-protein coupled receptors (GPCRs), which are often overexpressed in various types of tumors. The peptide subfamily of GPCRs is the pivot of the current article owing to the high affinity and specificity to and of their cognate peptide ligands, and the proven efficacy of peptide-based therapeutics. The article summarizes various ectopically expressed peptide GPCRs in lung cancer, namely, Cholecystokinin-B/Gastrin receptor, the Bombesin receptor family, Bradykinin B1 and B2 receptors, Arginine vasopressin receptors 1a, 1b and 2, and the Somatostatin receptor type 2. The autocrine growth and pro-proliferative pathways they mediate, and the distinct tumor-inhibitory effects of somatostatin receptors are then discussed. The next section covers how these pathways may be influenced or 'corrected' through therapeutics (involving agonists and antagonists) targeting the overexpressed peptide GPCRs. The review proceeds on to Nano-scaled delivery platforms, which enclose chemotherapeutic agents and are decorated with peptide ligands on their external surface, as an effective means of targeting cancer cells. We conclude that targeting these overexpressed peptide GPCRs is potentially evolving as a highly promising form of lung cancer therapy.
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Affiliation(s)
- Mahjabin Khan
- Laboratory of Brain-Gut Research, School of Chinese Medicine, Hong Kong Baptist University, HKSAR, Kowloon Tong, P.R. China
| | - Tao Huang
- Laboratory of Brain-Gut Research, School of Chinese Medicine, Hong Kong Baptist University, HKSAR, Kowloon Tong, P.R. China
| | - Cheng-Yuan Lin
- Laboratory of Brain-Gut Research, School of Chinese Medicine, Hong Kong Baptist University, HKSAR, Kowloon Tong, P.R. China
- YMU-HKBU Joint Laboratory of Traditional Natural Medicine, Yunnan Minzu University, Kunming, P.R. China
| | - Jiang Wu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, P. R. China
| | - Bao-Min Fan
- YMU-HKBU Joint Laboratory of Traditional Natural Medicine, Yunnan Minzu University, Kunming, P.R. China
| | - Zhao-Xiang Bian
- Laboratory of Brain-Gut Research, School of Chinese Medicine, Hong Kong Baptist University, HKSAR, Kowloon Tong, P.R. China
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Sun L, Qian Q, Sun G, Mackey LV, Fuselier JA, Coy DH, Yu CY. Valproic acid induces NET cell growth arrest and enhances tumor suppression of the receptor-targeted peptide-drug conjugate via activating somatostatin receptor type II. J Drug Target 2015. [PMID: 26211366 DOI: 10.3109/1061186x.2015.1066794] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND Human pancreatic carcinoids, a type of neuroendocrine tumors, are asymptomatic and difficult to diagnose, with the effects of traditional anti-cancer therapies being limited. The histone deacetylase (HDAC) inhibitor valproic acid (VPA) was evaluated for its effects alone and in combination with receptor-targeting peptide-drug conjugate via increasing drug internalization. MATERIALS AND METHODS The in vitro and in vivo assays were used to evaluate the effects of VPA and somatostatin receptor-targeting camptothecin-somatostatin conjugate (CPT-SST). RESULTS VPA induced proliferation suppression, cell apoptosis and cell cycle arrest. VPA acts as a HDAC inhibitor to induce a decrease of HDAC4 and an increase of acetylated histone 4 (AcH4). Meanwhile, most importantly, besides activating Notch signaling, VPA was observed to stimulate the expression of somatostatin receptor type 2 (SSTR2) that has been applied for receptor-targeting therapies. This characteristic was used for a combination therapy of VPA and CPT-SST. The combination displayed much more potent anti-tumor effects on carcinoid tumor growth by increasing SSTR2 density and drug internalization in target tumor cells. CONCLUSION The combination of VPA and a SSTR2-targeting agent provides us a promising approach in treatment of carcinoid tumors.
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Affiliation(s)
- Lichun Sun
- a Department of Pharmacy , The Fifth People's Hospital of Shanghai, Fudan University , Shanghai , China .,b Department of Medicine , Peptide Research Laboratories, Tulane Health Sciences Center , New Orleans , LA , USA , and
| | - Qingqing Qian
- a Department of Pharmacy , The Fifth People's Hospital of Shanghai, Fudan University , Shanghai , China
| | - Guangchun Sun
- a Department of Pharmacy , The Fifth People's Hospital of Shanghai, Fudan University , Shanghai , China
| | - L Vienna Mackey
- b Department of Medicine , Peptide Research Laboratories, Tulane Health Sciences Center , New Orleans , LA , USA , and
| | - Joseph A Fuselier
- b Department of Medicine , Peptide Research Laboratories, Tulane Health Sciences Center , New Orleans , LA , USA , and
| | - David H Coy
- b Department of Medicine , Peptide Research Laboratories, Tulane Health Sciences Center , New Orleans , LA , USA , and
| | - Cui-Yun Yu
- b Department of Medicine , Peptide Research Laboratories, Tulane Health Sciences Center , New Orleans , LA , USA , and.,c Department of Pharmacy , Institute of Pharmacy & Pharmacology, University of South China , Hengyang , China
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9
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Bonasoni P, Reyes J, Keating S, Cutz E, Taylor G. The distribution and frequency of pulmonary neuroendocrine cells in Down syndrome fetal lungs. Fetal Pediatr Pathol 2014; 33:157-65. [PMID: 24798587 DOI: 10.3109/15513815.2014.886001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The pulmonary neuroendocrine cells (PNEC) are located in the epithelial lining of the airways and consist of solitary neuroendocrine cells (NEC) and NEC clusters, the neuroepithelial bodies (NEB). During fetal life, PNEC are the first to differentiate within the primitive airway epithelium, and bombesin expression favors branching of the respiratory tree. We investigated PNEC in Down syndrome (DS), where the lungs often show enlarged and reduced number of alveoli. Immunohistochemistry for bombesin and synaptophysin, PNEC markers, was evaluated in fetal lungs from 15 cases of DS and 11 age-matched controls from the 17th to 23rd week of gestation. Morphometric analysis assessed PNEC in the mucosal lining of each lung, expressed as number/mm. Nonparametric Mann-Whitney U test showed no statistical difference in frequency of PNEC in DS and controls. Our findings suggest that, at least in late second trimester, the distribution and frequency of PNEC in DS fetuses is not altered.
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Di Florio A, Sancho V, Moreno P, Fave GD, Jensen RT. Gastrointestinal hormones stimulate growth of Foregut Neuroendocrine Tumors by transactivating the EGF receptor. BIOCHIMICA ET BIOPHYSICA ACTA 2013; 1833:573-82. [PMID: 23220008 PMCID: PMC3556220 DOI: 10.1016/j.bbamcr.2012.11.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2012] [Revised: 11/22/2012] [Accepted: 11/24/2012] [Indexed: 02/07/2023]
Abstract
Foregut neuroendocrine tumors [NETs] usually pursuit a benign course, but some show aggressive behavior. The treatment of patients with advanced NETs is marginally effective and new approaches are needed. In other tumors, transactivation of the EGF receptor (EGFR) by growth factors, gastrointestinal (GI) hormones and lipids can stimulate growth, which has led to new treatments. Recent studies show a direct correlation between NET malignancy and EGFR expression, EGFR inhibition decreases basal NET growth and an autocrine growth effect exerted by GI hormones, for some NETs. To determine if GI hormones can stimulate NET growth by inducing transactivation of EGFR, we examined the ability of EGF, TGFα and various GI hormones to stimulate growth of the human foregut carcinoid,BON, the somatostatinoma QGP-1 and the rat islet tumor,Rin-14B-cell lines. The EGFR tyrosine-kinase inhibitor, AG1478 strongly inhibited EGF and the GI hormones stimulated cell growth, both in BON and QGP-1 cells. In all the three neuroendocrine cell lines studied, we found EGF, TGFα and the other growth-stimulating GI hormones increased Tyr(1068) EGFR phosphorylation. In BON cells, both the GI hormones neurotensin and a bombesin analogue caused a time- and dose-dependent increase in EGFR phosphorylation, which was strongly inhibited by AG1478. Moreover, we found this stimulated phosphorylation was dependent on Src kinases, PKCs, matrix metalloproteinase activation and the generation of reactive oxygen species. These results raise the possibility that disruption of this signaling cascade by either EGFR inhibition alone or combined with receptor antagonists may be a novel therapeutic approach for treatment of foregut NETs/PETs.
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Affiliation(s)
- Alessia Di Florio
- Digestive Diseases Branch, NIDDK, National Institutes of Health, Bethesda, MD 20892-1804, USA
| | - Veronica Sancho
- Digestive Diseases Branch, NIDDK, National Institutes of Health, Bethesda, MD 20892-1804, USA
| | - Paola Moreno
- Digestive Diseases Branch, NIDDK, National Institutes of Health, Bethesda, MD 20892-1804, USA
| | - Gianfranco Delle Fave
- Digestive and Liver Disease Unit, II Medical School, University La Sapienza, S. Andrea Hospital, Via Di Grottarossa 00189, Rome, Italy
| | - Robert T. Jensen
- Digestive Diseases Branch, NIDDK, National Institutes of Health, Bethesda, MD 20892-1804, USA
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11
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Hafiz S, Dennis JC, Schwartz D, Judd R, Tao YX, Khazal K, Akingbemi B, Mo XL, Abdel-Mageed AB, Morrison E, Mansour M. Expression of melanocortin receptors in human prostate cancer cell lines: MC2R activation by ACTH increases prostate cancer cell proliferation. Int J Oncol 2012; 41:1373-80. [PMID: 22842514 DOI: 10.3892/ijo.2012.1574] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Accepted: 05/08/2012] [Indexed: 11/05/2022] Open
Abstract
The melanocortin receptors (MCRs 1-5) are G protein coupled-receptors (GPCRs) that regulate food intake, inflammation, skin pigmentation, sexual function and steroidogenesis. Their peptide ligands, the melanocortins, are α-, β- and γ-melanocyte-stimulating hormone and adrenocorticotropic hormone (ACTH) all of which are secreted from the anterior pituitary gland under hypothalamic control. MC2R binds ACTH but has no affinity for the other melanocortins and is, thereby, pharmacologically different from MCRs that bind those ligands. Evidence suggests that elevated GPCRs transactivate the androgen receptor (AR), the critical mediator of prostate cell growth, and consequently promote prostate cancer cell proliferation. It may be that reduced central melanocortin signaling is coincidental with reversal of prostate cancer cachexia, but no data are available on the expression of, or the role for, MCRs in prostate cancer. Here, we show that MCR (1-5) mRNAs are expressed in androgen-dependent LNCaP and androgen-independent PC3 and DU-145 human prostate cancer cell lines. Further, MC2R, the specific target of ACTH, is expressed in LNCaP, PC3 and DU-145 cells. Among the several synthetic MCR peptide ligands that we used, only ACTH promoted concentration-dependent cell proliferation in the three cell lines as shown by MTT cell proliferation assay. In LNCaP cells, the effect was additive with testosterone stimulation and was partially blunted with SHU9119, a non-selective MCR antagonist. In the same cells, ACTH induced cAMP production and increased AR nuclear labeling in immunocytochemical assays. Our observations suggest that MC2R is involved in prostate carcinogenesis and that targeting MC2R signaling may provide a novel avenue in prostate carcinoma treatment.
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Affiliation(s)
- Saly Hafiz
- Department of Anatomy, Physiology, and Pharmacology, College of Veterinary Medicine, Auburn University, Auburn, AL, USA
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12
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Franko-Tobin LG, Mackey LV, Huang W, Song X, Jin B, Luo J, Morris LM, Liu M, Fuselier JA, Coy DH, Wu L, Sun L. Notch1-mediated tumor suppression in cervical cancer with the involvement of SST signaling and its application in enhanced SSTR-targeted therapeutics. Oncologist 2012; 17:220-32. [PMID: 22291092 DOI: 10.1634/theoncologist.2011-0269] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The role of Notch signaling in cervical cancer is seemingly controversial. To confirm the function of Notch signaling in this type of cancer, we established a stable Notch1-activated cervical cancer HeLa cell line. We found that Notch1 activation resulted in apoptosis, cell cycle arrest, and tumor suppression. At the molecular level, we found that a variety of genes associated with cyclic AMP, G protein-coupled receptor, and cancer signaling pathways contributed to Notch1-mediated tumor suppression. We observed that the expression of somatostatin (SST) was dramatically induced by Notch1 signaling activation, which was accompanied by enhanced expression of the cognate SST receptor subtype 1 (SSTR1) and SSTR2. Certain genes, such as tumor protein 63 (TP63, p63), were upregulated, whereas others, such as B-cell lymphoma 2 (BCL-2), Myc, Akt, and STAT3, were downregulated. Subsequently, knockdown of Notch1-induced SST reversed Notch1-induced decrease of BCL-2 and increase of p63, indicating that Notch1-induced tumor suppression may be partly through upregulating SST signaling. Our findings support a possible crosstalk between Notch signaling and SST signaling. Moreover, Notch-induced SSTR activation could enhance SSTR-targeted cancer chemotherapy. Valproic acid (VPA), a histone deacetylase inhibitor, suppressed cell growth and upregulated the expression of Notch1 and SSTR2. A combination therapy with VPA and the SSTR2-targeting cytotoxic conjugate CPT-SST strongly led to greater suppression, as compared to each alone. Our findings thus provide us with a promising clinical opportunity for enhanced cancer therapy using combinations of Notch1-activating agents and SSTR2-targeting agents.
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Affiliation(s)
- Laura G Franko-Tobin
- Department of Medicine, Peptide Research Laboratories, Tulane Health Sciences Center, New Orleans, Louisiana 70112, USA
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