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Abstract
Neuroblastoma (NB) is the most common solid childhood tumor outside the brain and causes 15% of childhood cancer-related mortality. The main drivers of NB formation are neural crest cell-derived sympathoadrenal cells that undergo abnormal genetic arrangements. Moreover, NB is a complex disease that has high heterogeneity and is therefore difficult to target for successful therapy. Thus, a better understanding of NB development helps to improve treatment and increase the survival rate. One of the major causes of sporadic NB is known to be MYCN amplification and mutations in ALK (anaplastic lymphoma kinase) are responsible for familial NB. Many other genetic abnormalities can be found; however, they are not considered as driver mutations, rather they support tumor aggressiveness. Tumor cell elimination via cell death is widely accepted as a successful technique. Therefore, in this review, we provide a thorough overview of how different modes of cell death and treatment strategies, such as immunotherapy or spontaneous regression, are or can be applied for NB elimination. In addition, several currently used and innovative approaches and their suitability for clinical testing and usage will be discussed. Moreover, significant attention will be given to combined therapies that show more effective results with fewer side effects than drugs targeting only one specific protein or pathway.
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52
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Czapiewski P, Kunc M, Haybaeck J. Genetic and molecular alterations in olfactory neuroblastoma: implications for pathogenesis, prognosis and treatment. Oncotarget 2018; 7:52584-52596. [PMID: 27256979 PMCID: PMC5239575 DOI: 10.18632/oncotarget.9683] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Accepted: 05/19/2016] [Indexed: 12/11/2022] Open
Abstract
Olfactory neuroblastoma (ONB, Esthesioneuroblastoma) is an infrequent neoplasm of the head and neck area derived from olfactory neuroepithelium. Despite relatively good prognosis a subset of patients shows recurrence, progression and/or metastatic disease, which requires additional treatment. However, neither prognostic nor predictive factors are well specified. Thus, we performed a literature search for the currently available data on disturbances in molecular pathways, cytogenetic changes and results gained by next generation sequencing (NGS) approaches in ONB in order to gain an overview of genetic alterations which might be useful for treating patients with ONB. We present briefly ONB molecular pathogenesis and propose potential therapeutic targets and prognostic factors. Possible therapeutic targets in ONB include: receptor tyrosine kinases (c-kit, PDGFR-b, TrkB; EGFR); somatostatin receptor; FGF-FGFR1 signaling; Sonic hedgehog pathway; apoptosis-related pathways (Bcl-2, TRAIL) and neoangiogenesis (VEGF; KDR). Furthermore, we compare high- and low-grade ONB, and describe its frequent mimicker: sinonasal neuroendocrine carcinoma. ONB is often a therapeutic challenge, so our goal should be the implementation of acquired knowledge into clinical practice, especially at pretreated, recurrent and metastatic stages. Moreover, the multicenter molecular studies are needed to increase the amount of available data.
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Affiliation(s)
- Piotr Czapiewski
- Department of Pathomorphology, Medical University of Gdańsk, Gdańsk, Poland
| | - Michał Kunc
- Faculty of Medicine, Medical University of Gdańsk, Gdańsk, Poland
| | - Johannes Haybaeck
- Department of Neuropathology, Institute of Pathology, Medical University of Graz, Graz, Austria
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53
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Cook PJ, Thomas R, Kannan R, de Leon ES, Drilon A, Rosenblum MK, Scaltriti M, Benezra R, Ventura A. Somatic chromosomal engineering identifies BCAN-NTRK1 as a potent glioma driver and therapeutic target. Nat Commun 2017; 8:15987. [PMID: 28695888 PMCID: PMC5508201 DOI: 10.1038/ncomms15987] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 05/19/2017] [Indexed: 12/12/2022] Open
Abstract
The widespread application of high-throughput sequencing methods is resulting in the identification of a rapidly growing number of novel gene fusions caused by tumour-specific chromosomal rearrangements, whose oncogenic potential remains unknown. Here we describe a strategy that builds upon recent advances in genome editing and combines ex vivo and in vivo chromosomal engineering to rapidly and effectively interrogate the oncogenic potential of genomic rearrangements identified in human brain cancers. We show that one such rearrangement, an microdeletion resulting in a fusion between Brevican (BCAN) and Neurotrophic Receptor Tyrosine Kinase 1 (NTRK1), is a potent oncogenic driver of high-grade gliomas and confers sensitivity to the experimental TRK inhibitor entrectinib. This work demonstrates that BCAN-NTRK1 is a bona fide human glioma driver and describes a general strategy to define the oncogenic potential of novel glioma-associated genomic rearrangements and to generate accurate preclinical models of this lethal human cancer.
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Affiliation(s)
- Peter J Cook
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Rozario Thomas
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA.,Department of Molecular Biology, Weill Cornell Graduate School of Medical Sciences of Cornell University, New York, New York 10065, USA
| | - Ram Kannan
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Esther Sanchez de Leon
- Department of Molecular Biology, Weill Cornell Graduate School of Medical Sciences of Cornell University, New York, New York 10065, USA
| | - Alexander Drilon
- Thoracic Oncology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Marc K Rosenblum
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Maurizio Scaltriti
- Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA.,Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Robert Benezra
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
| | - Andrea Ventura
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, New York 10065, USA
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54
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Yang M, Pan Z, Huang K, Büsche G, Feuerhake F, Chaturvedi A, Nie D, Heuser M, Thol F, von Neuhoff N, Ganser A, Li Z. Activation of TRKA receptor elicits mastocytosis in mice and is involved in the development of resistance to KIT-targeted therapy. Oncotarget 2017; 8:73871-73883. [PMID: 29088753 PMCID: PMC5650308 DOI: 10.18632/oncotarget.18027] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 05/08/2017] [Indexed: 12/03/2022] Open
Abstract
The neurotrophins (NTs) play a key role in neuronal survival and maintenance. The TRK (tropomyosin-related kinase) tyrosine kinase receptors (TRKA, TRKB, TRKC) are high affinity receptors for NTs. There is increasing data demonstrating an important role of the TRK family in cancer initiation and progression. NTs have been known for many years to promote chemotaxis, maturation, and survival of mast cells. However, the role of NT signaling in the pathogenesis of mastocytosis is not well understood. In this study, we demonstrate that activation of TRKA by its ligand nerve growth factor (NGF) is potent to trigger a disease in mice with striking similarities to human systemic mastocytosis (SM). Moreover, activation of TRKA by NGF strongly rescues KIT inhibition-induced cell death of mast cell lines and primary mast cells from patients with SM, and this rescue effect can be efficiently blocked by entrectinib (a new pan TRK specific inhibitor). HMC-1 mast cell leukemia cells that are resistant to KIT inhibition induced by TRKA activation show reactivation of MAPK/ERK (extracellular signal-regulated kinase) and strong upregulation of early growth response 3 (EGR3), suggesting an important role of MAPK-EGR3 axis in the development of resistance to KIT inhibition. Targeting both TRK and KIT significantly prolongs survival of mice xenotransplanted with HMC-1 cells compared with targeting KIT alone. Thus, these data strongly suggest that TRKA signaling can improve neoplastic mast cell fitness. This might explain at least in part why treatment with KIT inhibitors alone so far has been disappointing in most published clinical trials for mastocytosis. Our data suggest that targeting both KIT and TRKs might improve efficacy of molecular therapy in SM with KIT mutations.
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Affiliation(s)
- Min Yang
- Department of Hematology, Hemostasis, Oncology, and Stem Cell Transplantation, Hannover Medical School, Hannover, Germany
| | - Zengkai Pan
- Department of Hematology, Hemostasis, Oncology, and Stem Cell Transplantation, Hannover Medical School, Hannover, Germany
| | - Kezhi Huang
- Department of Hematology, Hemostasis, Oncology, and Stem Cell Transplantation, Hannover Medical School, Hannover, Germany.,Department of Hematology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Guntram Büsche
- Institute of Pathology, Hannover Medical School, Hannover, Germany
| | | | - Anuhar Chaturvedi
- Department of Hematology, Hemostasis, Oncology, and Stem Cell Transplantation, Hannover Medical School, Hannover, Germany
| | - Danian Nie
- Department of Hematology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China
| | - Michael Heuser
- Department of Hematology, Hemostasis, Oncology, and Stem Cell Transplantation, Hannover Medical School, Hannover, Germany
| | - Felicitas Thol
- Department of Hematology, Hemostasis, Oncology, and Stem Cell Transplantation, Hannover Medical School, Hannover, Germany
| | - Nils von Neuhoff
- Institute of Pathology, Hannover Medical School, Hannover, Germany
| | - Arnold Ganser
- Department of Hematology, Hemostasis, Oncology, and Stem Cell Transplantation, Hannover Medical School, Hannover, Germany
| | - Zhixiong Li
- Department of Hematology, Hemostasis, Oncology, and Stem Cell Transplantation, Hannover Medical School, Hannover, Germany
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55
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Abstract
In the last few years, exciting properties have emerged regarding the activation, signaling, mechanisms of action, and therapeutic targeting of the two types of neurotrophin receptors: the p75NTR with its intracellular and extracellular peptides, the Trks, their precursors and their complexes. This review summarizes these new developments, with particular focus on neurodegenerative diseases. Based on the evolving knowledge, innovative concepts have been formulated regarding the pathogenesis of these diseases, especially the Alzheimer's and two other, the Parkinson's and Huntington's diseases. The medical progresses include original procedures of diagnosis, started from studies in mice and now investigated for human application, based on innovative classes of receptor agonists and blockers. In parallel, comprehensive studies have been and are being carried out for the development of drugs. The relevance of these studies is based on the limitations of the therapies employed until recently, especially for the treatment of Alzheimer's patients. Starting from well known drugs, previously employed for non-neurodegenerative diseases, the ongoing progress has lead to the development of small molecules that cross rapidly the blood-brain barrier. Among these molecules the most promising are specific blockers of the p75NTR receptor. Additional drugs, that activate Trk receptors, were shown effective against synaptic loss and memory deficits. In the near future such approaches, coordinated with treatments with monoclonal antibodies and with developments in the microRNA field, are expected to improve the therapy of neurodegenerative diseases, and may be relevant also for other human disease conditions.
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Affiliation(s)
- Jacopo Meldolesi
- Department of Neuroscience, Vita-Salute San Raffaele University and Scientific Institute San Raffaele, via Olgettina 58, 20132 Milan, Italy.
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56
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De Mariano M, Stigliani S, Moretti S, Parodi F, Croce M, Bernardi C, Pagano A, Tonini GP, Ferrini S, Longo L. A genome-wide microRNA profiling indicates miR-424-5p and miR-503-5p as regulators of ALK expression in neuroblastoma. Oncotarget 2017; 8:56518-56532. [PMID: 28915608 PMCID: PMC5593579 DOI: 10.18632/oncotarget.17033] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 03/29/2017] [Indexed: 12/30/2022] Open
Abstract
The discovery of missense mutations of ALK gene identified this receptor tyrosine kinase as a therapeutic target in neuroblastoma (NB). Moreover, a high level of ALK protein has been associated with metastatic NB cases and with a worse prognosis, suggesting that also ALK overexpression is involved in NB tumorigenesis. Since miRNAs play key roles in the regulation of gene expression we aimed at identifying those miRNAs that can regulate ALK in NB. We therefore analyzed the genome-wide expression profile of miRNAs in two sample sets of 16 NB cell lines and 22 NB samples by using miRNA microarrays. Both sample sets were then divided into two subgroups showing high (ALK+) or low/absent (ALK-) expression of ALK. Results showed a down-regulation of 30 and 23 miRNAs (p-value <0.05) in the ALK+ group in NB cell lines and samples, respectively. Validation analysis indicated that miR-424-5p and miR-503-5p, belonging to the same cluster, were differentially expressed in both NB cell lines and tumor samples. Although only miR-424-5p showed a direct binding to ALK 3′-UTR, both miRNAs led to a remarkable decreasing of ALK protein as well as to the inhibition of cell viability in ALK+ NB cell lines. In conclusion, our data indicate that both miR-424-5p and miR-503-5p are involved in regulating ALK expression in NB, either by directly targeting ALK receptor or indirectly, and may thus serve as potential therapeutic tools in ALK dependent NBs.
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Affiliation(s)
- Marilena De Mariano
- UOC Bioterapie, Dipartimento di Terapie Oncologiche Integrate, IRCCS AOU San Martino-IST, Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy
| | - Sara Stigliani
- UOS Fisiopatologia della Riproduzione Umana, Dipartimento di Chirurgia Generale, Specialistica ed Oncologica, IRCCS AOU San Martino-IST, Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy
| | - Stefano Moretti
- Université Paris-Dauphine, PSL Research University, CNRS, Department UMR [7243], LAMSADE, Paris, France
| | - Federica Parodi
- UOC Bioterapie, Dipartimento di Terapie Oncologiche Integrate, IRCCS AOU San Martino-IST, Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy
| | - Michela Croce
- UOC Bioterapie, Dipartimento di Terapie Oncologiche Integrate, IRCCS AOU San Martino-IST, Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy
| | - Cinzia Bernardi
- Centre of Excellence for Biomedical Research (CEBR), University of Genoa, Genoa, Italy
| | - Aldo Pagano
- Dipartimento di Terapie Oncologiche Integrate, IRCCS AOU San Martino-IST, Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy.,Department of Experimental Medicine (DIMES), University of Genoa, Genoa, Italy
| | - Gian Paolo Tonini
- Neuroblastoma Laboratory, Pediatric Research Institute, Città della Speranza, Padua, Italy
| | - Silvano Ferrini
- UOC Bioterapie, Dipartimento di Terapie Oncologiche Integrate, IRCCS AOU San Martino-IST, Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy
| | - Luca Longo
- UOC Bioterapie, Dipartimento di Terapie Oncologiche Integrate, IRCCS AOU San Martino-IST, Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy
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57
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Applebaum MA, Desai AV, Glade Bender JL, Cohn SL. Emerging and investigational therapies for neuroblastoma. Expert Opin Orphan Drugs 2017; 5:355-368. [PMID: 29062613 PMCID: PMC5649635 DOI: 10.1080/21678707.2017.1304212] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 03/06/2017] [Indexed: 02/06/2023]
Abstract
INTRODUCTION Treatment for children with clinically aggressive, high-risk neuroblastoma remains challenging. Less than 50% of patients with high-risk neuroblastoma will survive long-term with current therapies, and survivors are at risk for serious treatment-related late toxicities. Here, we review new and evolving treatments that may ultimately improve outcome for children with high-risk neuroblastoma with decreased potential for late adverse events. AREAS COVERED New strategies for treating high-risk neuroblastoma are reviewed including: radiotherapy, targeted cytotoxics, biologics, immunotherapy, and molecularly targeted agents. Recently completed and ongoing neuroblastoma clinical trials testing these novel treatments are highlighted. In addition, we discuss ongoing clinical trials designed to evaluate precision medicine approaches that target actionable somatic mutations and oncogenic cellular pathways. EXPERT OPINION Advances in genomic medicine and molecular biology have led to the development of early phase studies testing biologically rational therapies targeting aberrantly activated cellular pathways. Because many of these drugs have a wider therapeutic index than standard chemotherapeutic agents, these treatments may be more effective and less toxic than current strategies. However, to effectively integrate these targeted strategies, robust predictive biomarkers must be developed that will identify patients who will benefit from these approaches and rapidly match treatments to patients at diagnosis.
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Affiliation(s)
- Mark A. Applebaum
- Department of Pediatrics, University of Chicago, Chicago, Illinois, 60637, United States of America
- Committee on Clinical Pharmacology and Pharmacogenomics, University of Chicago, Chicago, Illinois, 60637, United States of America
| | - Ami V. Desai
- Department of Pediatrics, University of Chicago, Chicago, Illinois, 60637, United States of America
| | - Julia L. Glade Bender
- Department of Pediatrics, Columbia University Medical Center, New York, New York, 10032
- Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, New York, 10032
| | - Susan L. Cohn
- Department of Pediatrics, University of Chicago, Chicago, Illinois, 60637, United States of America
- Committee on Clinical Pharmacology and Pharmacogenomics, University of Chicago, Chicago, Illinois, 60637, United States of America
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58
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Bailey JJ, Schirrmacher R, Farrell K, Bernard-Gauthier V. Tropomyosin receptor kinase inhibitors: an updated patent review for 2010-2016 - Part II. Expert Opin Ther Pat 2017; 27:831-849. [PMID: 28270021 DOI: 10.1080/13543776.2017.1297797] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
INTRODUCTION TrkA/B/C receptor activation supports growth, survival, and differentiation of discrete neuronal populations during development, adult life, and ageing but also plays numerous roles in human disease onset and progression. Trk-specific inhibitors have therapeutic applications in cancer and pain and thus constitute a growing area of interest in oncology and neurology. There has been substantial growth in the number of structural classes of Trk inhibitors and the number of industrial entrants to the Trk inhibitor field over the past six years. Areas covered: In Part II of this two-part review, the discussion of recent patent literature covering Trk family inhibitors is continued from Part I and clinical research with Trk inhibitors is considered. Expert opinion: Trk has been molecularly targeted for over a decade resulting in the progressive evolution of structurally diversified Trk inhibitors arising from scaffold hopping and HTS efforts. Correspondingly, there have been a growing number of clinical investigations utilizing Trk inhibitors in recent years, with a particular focus on the treatment of NTRK-fusion positive cancers and chronic pain. The observed potential of Trk inhibitors to cause adverse CNS side effects however suggests the need for a more rigorous consideration of BBB permeation capabilities during drug development.
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Affiliation(s)
- Justin J Bailey
- a Faculty of Medicine & Dentistry, Department of Oncology , University of Alberta , Edmonton , Canada
| | - Ralf Schirrmacher
- a Faculty of Medicine & Dentistry, Department of Oncology , University of Alberta , Edmonton , Canada
| | - Kristen Farrell
- a Faculty of Medicine & Dentistry, Department of Oncology , University of Alberta , Edmonton , Canada
| | - Vadim Bernard-Gauthier
- a Faculty of Medicine & Dentistry, Department of Oncology , University of Alberta , Edmonton , Canada
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59
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Esposito MR, Aveic S, Seydel A, Tonini GP. Neuroblastoma treatment in the post-genomic era. J Biomed Sci 2017; 24:14. [PMID: 28178969 PMCID: PMC5299732 DOI: 10.1186/s12929-017-0319-y] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 01/31/2017] [Indexed: 02/07/2023] Open
Abstract
Neuroblastoma is an embryonic malignancy of early childhood originating from neural crest cells and showing heterogeneous biological, morphological, genetic and clinical characteristics. The correct stratification of neuroblastoma patients within risk groups (low, intermediate, high and ultra-high) is critical for the adequate treatment of the patients. High-throughput technologies in the Omics disciplines are leading to significant insights into the molecular pathogenesis of neuroblastoma. Nonetheless, further study of Omics data is necessary to better characterise neuroblastoma tumour biology. In the present review, we report an update of compounds that are used in preclinical tests and/or in Phase I-II trials for neuroblastoma. Furthermore, we recapitulate a number of compounds targeting proteins associated to neuroblastoma: MYCN (direct and indirect inhibitors) and downstream targets, Trk, ALK and its downstream signalling pathways. In particular, for the latter, given the frequency of ALK gene deregulation in neuroblastoma patients, we discuss on second-generation ALK inhibitors in preclinical or clinical phases developed for the treatment of neuroblastoma patients resistant to crizotinib. We summarise how Omics drive clinical trials for neuroblastoma treatment and how much the research of biological targets is useful for personalised medicine. Finally, we give an overview of the most recent druggable targets selected by Omics investigation and discuss how the Omics results can provide us additional advantages for overcoming tumour drug resistance.
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Affiliation(s)
- Maria Rosaria Esposito
- Paediatric Research Institute, Fondazione Città della Speranza, Neuroblastoma Laboratory, Corso Stati Uniti, 4, Padua, 35127, Italy.
| | - Sanja Aveic
- Paediatric Research Institute, Fondazione Città della Speranza, Neuroblastoma Laboratory, Corso Stati Uniti, 4, Padua, 35127, Italy
| | - Anke Seydel
- Department of Biology, University of Padua, Padua, Italy
| | - Gian Paolo Tonini
- Paediatric Research Institute, Fondazione Città della Speranza, Neuroblastoma Laboratory, Corso Stati Uniti, 4, Padua, 35127, Italy
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60
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Abstract
In the last few years, exciting reports have emerged regarding the role of the two types of neurotrophin receptors, p75NTR and Trks, not only in neurons, where they were discovered, but also in non-neural cells and, especially, in numerous cancers, including breast, lung, colon-rectum, pancreas, prostate, glioblastoma, neuroblastoma, myeloma, and lymphoid tumors. Traditionally, p75NTR, activated by all neurotrophins and their precursors, is an inhibitor. In various cancers, however, activated p75NTR induces variable effects, from inhibition to stimulation of cell proliferation, dependent on their direct or coordinate/indirect mechanism(s) of action. TrkA, TrkB, and TrkC, activated by distinct neurotrophins, are high affinity stimulatory receptors. In cancers, activation of Trks, especially of TrkB, are stimulators of cell proliferation, aggressiveness, and metastases. In rare cancers, these processes are due not to receptor activation but to fusion or mutation of the encoding genes. A considerable panel of anti-Trk drugs, developed recently, has been investigated both in vitro and in living mice for their effects on cancer cells. Many such drugs protect from cancers by preventing cell proliferation and inducing apoptosis. At present, these drugs are under control by trials, to promote introduction in human therapy. Moreover, anti-Trk drugs have been employed also in combination with classical chemotherapeutic drugs. So far, studies in mice have been positive. The chemotherapeutic/anti-receptor combinations exhibited in fact increased potency and down-regulation of resistance, with no increase of side effects.
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