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Alqahtani T, Kumarasamy V, Alghamdi SS, Suliman RS, Bin Saleh K, Alrashed MA, Aldhaeefi M, Sun D. Adefovir Dipivoxil as a Therapeutic Candidate for Medullary Thyroid Carcinoma: Targeting RET and STAT3 Proto-Oncogenes. Cancers (Basel) 2023; 15:cancers15072163. [PMID: 37046823 PMCID: PMC10093259 DOI: 10.3390/cancers15072163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 04/02/2023] [Accepted: 04/03/2023] [Indexed: 04/08/2023] Open
Abstract
Aberrant gene expression is often linked to the progression of various cancers, making the targeting of oncogene transcriptional activation a potential strategy to control tumor growth and development. The RET proto-oncogene’s gain-of-function mutation is a major cause of medullary thyroid carcinoma (MTC), which is part of multiple endocrine neoplasia type 2 (MEN2) syndrome. In this study, we used a cell-based bioluminescence reporter system driven by the RET promoter to screen for small molecules that potentially suppress the RET gene transcription. We identified adefovir dipivoxil as a transcriptional inhibitor of the RET gene, which suppressed endogenous RET protein expression in MTC TT cells. Adefovir dipivoxil also interfered with STAT3 phosphorylation and showed high affinity to bind to STAT3. Additionally, it inhibited RET-dependent TT cell proliferation and increased apoptosis. These results demonstrate the potential of cell-based screening assays in identifying transcriptional inhibitors for other oncogenes.
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Affiliation(s)
- Tariq Alqahtani
- Department of Pharmaceutical Sciences, College of Pharmacy, Ministry of National Guard Health Affairs, King Saud bin Abdulaziz University for Health Sciences, Riyadh 11481, Saudi Arabia
- Medical Research Core Facility and Platforms, King Abdullah International Medical Research Center (KAIMRC), Ministry of National Guard Health Affairs, Riyadh 11426, Saudi Arabia
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, AZ 85721, USA
| | - Vishnu Kumarasamy
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, AZ 85721, USA
- Department of Molecular and Cellular Biology, Roswell Park Cancer Center, Buffalo, NY 14203, USA
- Department of Cancer Genetics and Genomics, Roswell Park Cancer Center, Buffalo, NY 14203, USA
| | - Sahar Saleh Alghamdi
- Department of Pharmaceutical Sciences, College of Pharmacy, Ministry of National Guard Health Affairs, King Saud bin Abdulaziz University for Health Sciences, Riyadh 11481, Saudi Arabia
- Medical Research Core Facility and Platforms, King Abdullah International Medical Research Center (KAIMRC), Ministry of National Guard Health Affairs, Riyadh 11426, Saudi Arabia
| | - Rasha Saad Suliman
- Department of Pharmaceutical Sciences, College of Pharmacy, Ministry of National Guard Health Affairs, King Saud bin Abdulaziz University for Health Sciences, Riyadh 11481, Saudi Arabia
- Medical Research Core Facility and Platforms, King Abdullah International Medical Research Center (KAIMRC), Ministry of National Guard Health Affairs, Riyadh 11426, Saudi Arabia
- Pharmacy Department, Fatima College of Health Sciences, Almafrag, Abu Dhabi P.O. Box 3798, United Arab Emirates
| | - Khalid Bin Saleh
- Medical Research Core Facility and Platforms, King Abdullah International Medical Research Center (KAIMRC), Ministry of National Guard Health Affairs, Riyadh 11426, Saudi Arabia
- Department of pharmacy practice, College of Pharmacy, King Saud bin Abdulaziz University for Health Sciences, Riyadh 11481, Saudi Arabia
| | - Mohammed A. Alrashed
- Medical Research Core Facility and Platforms, King Abdullah International Medical Research Center (KAIMRC), Ministry of National Guard Health Affairs, Riyadh 11426, Saudi Arabia
- Department of pharmacy practice, College of Pharmacy, King Saud bin Abdulaziz University for Health Sciences, Riyadh 11481, Saudi Arabia
| | - Mohammed Aldhaeefi
- Department of Pharmaceutical Sciences, College of Pharmacy, Ministry of National Guard Health Affairs, King Saud bin Abdulaziz University for Health Sciences, Riyadh 11481, Saudi Arabia
- Medical Research Core Facility and Platforms, King Abdullah International Medical Research Center (KAIMRC), Ministry of National Guard Health Affairs, Riyadh 11426, Saudi Arabia
- Department of pharmacy practice, College of Pharmacy, King Saud bin Abdulaziz University for Health Sciences, Riyadh 11481, Saudi Arabia
| | - Daekyu Sun
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, Tucson, AZ 85721, USA
- Pharmacy Department, Fatima College of Health Sciences, Almafrag, Abu Dhabi P.O. Box 3798, United Arab Emirates
- Department of Clinical and Administrative Pharmacy Sciences, College of Pharmacy, Howard University, Washington, DC 20059, USA
- The BIO5 Institute, University of Arizona, Tucson, AZ 85721, USA
- Department of Cancer Biology, University of Arizona, Tucson, AZ 85724, USA
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2
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A Series of RET Fusion Spitz Neoplasms With Plaque-Like Silhouette and Dyscohesive Nesting of Epithelioid Melanocytes. Am J Dermatopathol 2020; 43:243-251. [PMID: 33742998 DOI: 10.1097/dad.0000000000001780] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
ABSTRACT Two distinct studies have shown that RET fusions are found in 3%-4% of Spitz neoplasms. RET fusions have been well described in papillary thyroid cancer, non-small-cell lung cancer, breast cancer, and soft-tissue mesenchymal tumors as well as some other neoplasms. However, there are no comprehensive descriptions to date of the characteristic morphologic, clinical, or genomic findings in RET fusion Spitz neoplasms. In this study, we identified 5 cases of RET fusion Spitz neoplasms. These tumors showed characteristic morphologic features which included plaque-like silhouette and monotonous epithelioid cytology with expansile and dyscohesive nesting. Four of 5 patients including 1 diagnosed as Spitz melanoma had clinical follow-up all of which was uneventful. Furthermore, we describe the genomic sequences in 4 of these cases, 2 of which have previously described KIF5B-RET fusion and 2 of which had a novel LMNA-RET fusion. We believe this report significantly contributes to our current knowledge regarding Spitz neoplasms and describes characteristics features which can help with recognition of the RET subgroup of Spitz.
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Al-Jundi M, Thakur S, Gubbi S, Klubo-Gwiezdzinska J. Novel Targeted Therapies for Metastatic Thyroid Cancer-A Comprehensive Review. Cancers (Basel) 2020; 12:E2104. [PMID: 32751138 PMCID: PMC7463725 DOI: 10.3390/cancers12082104] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 07/22/2020] [Accepted: 07/25/2020] [Indexed: 12/18/2022] Open
Abstract
The knowledge on thyroid cancer biology has grown over the past decade. Thus, diagnostic and therapeutic strategies to manage thyroid cancer are rapidly evolving. With new insights into tumor biology and cancer genetics, several novel therapies have been approved for the treatment of thyroid cancer. Tyrosine kinase inhibitors (TKIs), such as lenvatinib and sorafenib, have been successfully utilized for the treatment of radioactive iodine (RAI)-refractory metastatic differentiated thyroid cancer (DTC). In addition, pretreatment with mitogen-activated protein kinase (MAPK) inhibitors (trametinib and selumetinib) has been shown to restore RAI avidity in previously RAI-refractory DTCs. Local therapies, such as external beam radiation and radiofrequency/ethanol ablation, have also been employed for treatment of DTC. Vandetanib and cabozantinib are the two TKIs currently approved by the Food and Drug Administration (FDA) for the treatment of medullary thyroid cancer (MTC). Other novel therapies, such as peptide receptor radionuclide therapy and carcinoembryonic antigen (CEA) vaccine, have also been utilized in treating MTC. Ongoing trials on selective rearranged-during-transfection (RET) protooncogene inhibitors, such as LOXO-292 and BLU-667, have demonstrated promising results in the treatment of metastatic MTC resistant to non-selective TKIs. The FDA-approved BRAF/MEK inhibitor combination of dabrafenib and trametinib has revolutionized treatment of BRAFV600E mutation positive anaplastic thyroid cancer. Several other emerging classes of medications, such as gene fusion inhibitors and immune checkpoint inhibitors, are being actively investigated in several clinical trials. In this review, we describe the molecular landscape of thyroid cancer and novel targeted therapies and treatment combinations available for the treatment of metastatic thyroid cancer.
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Affiliation(s)
| | | | | | - Joanna Klubo-Gwiezdzinska
- Thyroid Tumors and Functional Thyroid Disorders Section, Metabolic Disease Branch, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20814, USA; (M.A.-J.); (S.T.); (S.G.)
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Joo LJS, Weiss J, Gill AJ, Clifton-Bligh R, Brahmbhatt H, MacDiarmid JA, Gild ML, Robinson BG, Zhao JT, Sidhu SB. RET Kinase-Regulated MicroRNA-153-3p Improves Therapeutic Efficacy in Medullary Thyroid Carcinoma. Thyroid 2019; 29:830-844. [PMID: 30929576 DOI: 10.1089/thy.2018.0525] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Background: Medullary thyroid carcinoma (MTC) presents a disproportionate number of thyroid cancer deaths due to limited treatment options beyond surgery. Gain-of-function mutations of the human REarranged during Transfection (RET) proto-oncogene have been well-established as the key driver of MTC tumorigenesis. RET has been targeted by tyrosine kinase inhibitors (TKIs), such as cabozantinib and vandetanib. However, clinical results have been disappointing, with regular dose reductions and inevitable progression. This study aimed to identify RET-regulated microRNAs (miRNAs) and explore their potential as novel therapeutic targets. Methods: Small RNA sequencing was performed in MTC TT cells before and after RET inhibition to identify RET-regulated miRNAs of significance. In vitro gain-of-function studies were performed to investigate cellular and molecular effects of potential miRNAs on cell phenotypes. Systemic delivery of miRNA in MTC xenografts using EDV™ nanocells, targeted to epidermal growth factor receptor on tumor cells, was employed to assess the therapeutic potential and possible modulation of TKI responses. Results: The study demonstrates the tumor suppressive role of a specific RET-regulated miRNA, microRNA-153-3p (miR-153-3p), in MTC. Targeted intravenous delivery of miR-153-3p impeded the tumor growth in MTC xenografts. Furthermore, combined treatment with miR-153-3p plus cabozantinib caused greater growth inhibition and appeared to reverse cabozantinib resistance. Mechanistically, miR-153-3p targets ribosomal protein S6 kinase B1 (RPS6KB1) of mTOR signaling and reduced downstream phosphorylation of Bcl-2 associated death promoter. Conclusion: This study provides evidence to establish systemic miRNA replacement plus TKIs as a novel therapeutic for patients with metastatic, progressive MTC.
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Affiliation(s)
- Lauren Jin Suk Joo
- 1 Cancer Genetics Laboratory, Kolling Institute, Northern Sydney Local Health District, Sydney, Australia
- 2 Faculty of Medicine and Health; University of Sydney, Sydney, Australia
| | | | - Anthony J Gill
- 2 Faculty of Medicine and Health; University of Sydney, Sydney, Australia
- 4 NSW Health Pathology, Department of Anatomical Pathology, Royal North Shore Hospital and Cancer Diagnosis and Pathology Group, Kolling Institute of Medical Research, Royal North Shore Hospital, Sydney, Australia
| | - Roderick Clifton-Bligh
- 1 Cancer Genetics Laboratory, Kolling Institute, Northern Sydney Local Health District, Sydney, Australia
- 2 Faculty of Medicine and Health; University of Sydney, Sydney, Australia
- 5 Department of Endocrinology; University of Sydney, Sydney, Australia
| | | | | | - Matti L Gild
- 1 Cancer Genetics Laboratory, Kolling Institute, Northern Sydney Local Health District, Sydney, Australia
- 5 Department of Endocrinology; University of Sydney, Sydney, Australia
| | - Bruce G Robinson
- 1 Cancer Genetics Laboratory, Kolling Institute, Northern Sydney Local Health District, Sydney, Australia
- 2 Faculty of Medicine and Health; University of Sydney, Sydney, Australia
- 5 Department of Endocrinology; University of Sydney, Sydney, Australia
| | - Jing Ting Zhao
- 1 Cancer Genetics Laboratory, Kolling Institute, Northern Sydney Local Health District, Sydney, Australia
- 2 Faculty of Medicine and Health; University of Sydney, Sydney, Australia
| | - Stan B Sidhu
- 1 Cancer Genetics Laboratory, Kolling Institute, Northern Sydney Local Health District, Sydney, Australia
- 2 Faculty of Medicine and Health; University of Sydney, Sydney, Australia
- 6 University of Sydney Endocrine Surgery Unit; Royal North Shore Hospital, University of Sydney, Sydney, Australia
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Joo LJS, Zhao JT, Gild ML, Glover AR, Sidhu SB. Epigenetic regulation of RET receptor tyrosine kinase and non-coding RNAs in MTC. Mol Cell Endocrinol 2018; 469:48-53. [PMID: 28315378 DOI: 10.1016/j.mce.2017.03.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 03/13/2017] [Accepted: 03/13/2017] [Indexed: 12/21/2022]
Abstract
Medullary thyroid carcinoma (MTC) is an aggressive and rare cancer with limited treatment options for metastatic disease. Due to this, there is a need for a better understanding of MTC biology in the hope of improved treatments. One area of improved understanding of cancer biology is epigenetics. Epigenetics is defined as cellular processes which alter gene expression independent of changes in the primary DNA sequence. These processes include modifications such as DNA methylation, microRNA deregulation and post-translational histone modifications, all of which have been implicated in tumorigenesis of MTC. Transcription of the main driver of MTC - the REarranged during Transfection (RET) proto-oncogene can also be modulated by epigenetic alterations. This review will present a review of MTC and its epigenetic links with a particular focus on targeting epigenetic mechanisms as novel therapeutic strategies.
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Affiliation(s)
- Lauren Jin Suk Joo
- Cancer Genetics Laboratory, Kolling Institute of Medical Research, Royal North Shore Hospital, The University of Sydney, St Leonards, NSW, Australia; Sydney Medical School Northern, Royal North Shore Hospital, The University of Sydney, St Leonards, Sydney, NSW, Australia
| | - Jing Ting Zhao
- Cancer Genetics Laboratory, Kolling Institute of Medical Research, Royal North Shore Hospital, The University of Sydney, St Leonards, NSW, Australia; Sydney Medical School Northern, Royal North Shore Hospital, The University of Sydney, St Leonards, Sydney, NSW, Australia
| | - Matti L Gild
- Sydney Medical School Northern, Royal North Shore Hospital, The University of Sydney, St Leonards, Sydney, NSW, Australia
| | - Anthony R Glover
- Sydney Medical School Northern, Royal North Shore Hospital, The University of Sydney, St Leonards, Sydney, NSW, Australia
| | - Stan B Sidhu
- Cancer Genetics Laboratory, Kolling Institute of Medical Research, Royal North Shore Hospital, The University of Sydney, St Leonards, NSW, Australia; Sydney Medical School Northern, Royal North Shore Hospital, The University of Sydney, St Leonards, Sydney, NSW, Australia; University of Sydney Endocrine Surgery Unit, Royal North Shore Hospital, St Leonards, NSW, Australia.
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Wang D, Liu J, Huo T, Tian Y, Zhao L. The role of microRNAs in colorectal liver metastasis: Important participants and potential clinical significances. Tumour Biol 2017. [PMID: 28651498 DOI: 10.1177/1010428317709640] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Colorectal cancer is one of the most common cancers in the world, and liver metastasis is the leading direct cause of cancer-related deaths in colorectal cancer. MicroRNA is involved in tumor metastasis in many aspects; mounting studies have shown that microRNAs play important roles in colorectal liver metastasis. Although lots of reviews about the association between microRNAs and colorectal cancer metastasis have been published, the reviews specifically focusing on microRNAs and colorectal liver metastasis are still lacking in the literature. To address this issue, here, we summarize the underlying mechanisms of microRNAs in colorectal liver metastasis and explore their potential clinical applications in this aspect.
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Affiliation(s)
- Dongxu Wang
- 1 School of Medicine and Life Sciences, University of Jinan-Shandong Academy of Medical Sciences, Jinan, China.,2 Shandong Academy of Medical Sciences, Jinan, China.,3 Shandong Cancer Hospital Affiliated to Shandong University, Jinan, China
| | - Jie Liu
- 1 School of Medicine and Life Sciences, University of Jinan-Shandong Academy of Medical Sciences, Jinan, China.,2 Shandong Academy of Medical Sciences, Jinan, China.,3 Shandong Cancer Hospital Affiliated to Shandong University, Jinan, China
| | - Tingting Huo
- 3 Shandong Cancer Hospital Affiliated to Shandong University, Jinan, China.,4 The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Yaowen Tian
- 1 School of Medicine and Life Sciences, University of Jinan-Shandong Academy of Medical Sciences, Jinan, China.,2 Shandong Academy of Medical Sciences, Jinan, China.,3 Shandong Cancer Hospital Affiliated to Shandong University, Jinan, China
| | - Lei Zhao
- 1 School of Medicine and Life Sciences, University of Jinan-Shandong Academy of Medical Sciences, Jinan, China.,2 Shandong Academy of Medical Sciences, Jinan, China.,3 Shandong Cancer Hospital Affiliated to Shandong University, Jinan, China.,4 The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
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Lin C, Wang S, Xie W, Zheng R, Gan Y, Chang J. Apatinib inhibits cellular invasion and migration by fusion kinase KIF5B-RET via suppressing RET/Src signaling pathway. Oncotarget 2016; 7:59236-59244. [PMID: 27494860 PMCID: PMC5312308 DOI: 10.18632/oncotarget.10985] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Accepted: 07/10/2016] [Indexed: 12/14/2022] Open
Abstract
The Rearranged during transfection (RET) fusion gene is a newly identified oncogenic mutation in non-small cell lung cancer (NSCLC). The aim of this study is to explore the biological functions of the gene in tumorigenesis and metastasis in RET gene fusion-driven preclinical models. We also investigate the anti-tumor activity of Apatinib, a potent inhibitor of VEGFR-2, PDGFR-β, c-Src and RET, in RET-rearranged lung adenocarcinoma, together with the mechanisms underlying. Our results suggested that KIF5B-RET fusion gene promoted cell invasion and migration, which were probably mediated through Src signaling pathway. Apatinib exerted its anti-cancer effect not only via cytotoxicity, but also via inhibition of migration and invasion by suppressing RET/Src signaling pathway, supporting a potential role for Apatinib in the treatment of KIF5B-RET driven tumors.
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Affiliation(s)
- Chen Lin
- Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai, 200032, P.R. China
| | - Shanshan Wang
- Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai, 200032, P.R. China
| | - Weiwei Xie
- Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai, 200032, P.R. China
| | - Rongliang Zheng
- Department of Nuclear Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, 510000, P.R. China
| | - Yu Gan
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200032, P.R. China
| | - Jianhua Chang
- Department of Medical Oncology, Fudan University Shanghai Cancer Center, Shanghai, 200032, P.R. China
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Lin C, Wang S, Xie W, Chang J, Gan Y. The RET fusion gene and its correlation with demographic and clinicopathological features of non-small cell lung cancer: a meta-analysis. Cancer Biol Ther 2015; 16:1019-28. [PMID: 25975578 DOI: 10.1080/15384047.2015.1046649] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
PURPOSE The RET fusion gene is a novel oncogene observed in a subset of NSCLC in recent years. Nevertheless, the results of epidemiological studies concerning the gene remain unclear. Thus, a meta-analysis was conducted to evaluate the correlation of RET fusion gene with demographic and clinicopathological features of NSCLC. METHODS PubMed, Embase, and Web of Science databases were searched to identify eligible studies. The association of RET fusion gene occurrence with gender, age, smoking status, histology type and tumor stage were analyzed in meta-analysis. Subgroup analysis according to patients' location (Asian and non-Asian) was also conducted. Odds ratio (OR) and 95% confidence interval (95% CI) were calculated to assess the correlation. RESULTS Nine studies with a total of 6,899 NSCLC patients met the inclusion criteria. A total of 84 patients with RET fusion gene were detected. The RET fusion gene was identified at significantly higher frequencies in female (OR = 0.55, 95%CI = 0.35-0.85) than male patients and in young (<60) patients (OR = 0.43, 95%CI = 0.19-0.99) than old patients (≤60), particularly in patients from Asian. A significant higher frequency was also identified in non-smokers (OR = 0.28, 95% CI = 0.16-0.49), and in patients with lung adenocarcinomas (OR = 3.59, 95%CI = 1.50-8.56). Additionally, no association between RET fusion gene and the TNM stage of tumor was observed. CONCLUSION RET fusion gene occurred predominantly in Asian females with younger age, in non-smokers, and in lung adenocarcinomas patients. This subset of NSCLC patients might be good candidates for personalized diagnostic and therapeutic approaches.
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Key Words
- ADC, Adenocarcinoma
- ARTN, Artemin
- CIs, Confidence Intervals
- EGFR, Epidermal Growth Factor Receptor
- GDNF, Glial cell line-derived Neurotrophic Factor
- NADC, Non-adenocarcinoma
- NRTN, Neurturin
- NSCLC, Non-Small Cell Lung Cancer
- OR, Odd Ratio
- PI3K, Phosphatidylinositol 3-kinase
- PSPN, Persephin
- RET
- RT-PCR, Real-Time Polymerase Chain Reaction
- SCLC, Small-cell lung cancer
- TKIs, Tyrosine Kinase Inhibitors
- clinicopathological features
- demographic features
- fusion
- meta-analysis
- non-small cell lung cancer
- targeted therapy
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Affiliation(s)
- Chen Lin
- a Department of Medical Oncology; Fudan University Shanghai Cancer Center ; Shanghai , China
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Mazumdar M, Adhikary A, Chakraborty S, Mukherjee S, Manna A, Saha S, Mohanty S, Dutta A, Bhattacharjee P, Ray P, Chattopadhyay S, Banerjee S, Chakraborty J, Ray AK, Sa G, Das T. Targeting RET to induce medullary thyroid cancer cell apoptosis: an antagonistic interplay between PI3K/Akt and p38MAPK/caspase-8 pathways. Apoptosis 2013; 18:589-604. [PMID: 23329180 DOI: 10.1007/s10495-013-0803-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Mutations in REarranged during Transfection (RET) receptor tyrosine, followed by the oncogenic activation of RET kinase is responsible for the development of medullary thyroid carcinoma (MTC) that responds poorly to conventional chemotherapy. Targeting RET, therefore, might be useful in tailoring surveillance of MTC patients. Here we showed that theaflavins, the bioactive components of black tea, successfully induced apoptosis in human MTC cell line, TT, by inversely modulating two molecular pathways: (i) stalling PI3K/Akt/Bad pathway that resulted in mitochondrial transmembrane potential (MTP) loss, cytochrome-c release and activation of the executioner caspases-9 and -3, and (ii) upholding p38MAPK/caspase-8/caspase-3 pathway via inhibition of Ras/Raf/ERK. Over-expression of either constitutively active myristoylated-Akt-cDNA (Myr-Akt-cDNA) or dominant-negative-caspase-8-cDNA (Dn-caspase-8-cDNA) partially blocked theaflavin-induced apoptosis, while co-transfection of Myr-Akt-cDNA and Dn-caspase-8-cDNA completely eradicated the effect of theaflavins thereby negating the possibility of existence of other pathways. A search for the upstream signaling revealed that theaflavin-induced disruption of lipid raft caused interference in anchorage of RET in lipid raft that in turn stalled phosphorylation of Ras and PI3Kinase. In such anti-survival cellular micro-environment, pro-apoptotic signals were triggered to culminate into programmed death of MTC cell. These findings not only unveil a hitherto unexplained mechanism underlying theaflavin-induced MTC death, but also validate RET as a promising and potential target for MTC therapy.
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Affiliation(s)
- Minakshi Mazumdar
- Division of Molecular Medicine, Bose Institute, P-1/12, Calcutta Improvement Trust Road, Scheme VII M, Kolkata, West Bengal, 700 054, India
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Mologni L, Redaelli S, Morandi A, Plaza-Menacho I, Gambacorti-Passerini C. Ponatinib is a potent inhibitor of wild-type and drug-resistant gatekeeper mutant RET kinase. Mol Cell Endocrinol 2013; 377:1-6. [PMID: 23811235 DOI: 10.1016/j.mce.2013.06.025] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 06/11/2013] [Accepted: 06/17/2013] [Indexed: 01/03/2023]
Abstract
RET kinase is aberrantly activated in thyroid cancers and in rare cases of lung and colon cancer, and has been validated as a molecular target in these tumors. Vandetanib was recently approved for the treatment of medullary thyroid cancer. However, vandetanib is ineffective in vitro against RET mutants carrying bulky aminoacids at position 804, the gatekeeper residue, similarly to drug-resistant BCR-ABL mutants in chronic myeloid leukemia. Ponatinib is a multi-target kinase inhibitor that was recently approved for treatment-refractory Philadelphia-positive leukemia. We show here potent inhibition of oncogenic RET by ponatinib, including the drug-insensitive V804M/L mutants. Ponatinib inhibited the growth of RET+ and BCR-ABL+ cells with similar potency, while not affecting RET-negative cells. Both in biochemical and in cellular assays ponatinib compared favorably with known RET inhibitors, such as vandetanib, cabozantinib, sorafenib, sunitinib and motesanib, used as reference compounds. We suggest that ponatinib should be considered for the treatment of RET+ tumors, in particular those expressing vandetanib-resistant V804M/L mutations.
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Affiliation(s)
- Luca Mologni
- Dept. of Health Sciences, University of Milano-Bicocca, via Cadore 48, 20900 Monza, Italy.
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Qi Q, Ye K. The roles of PIKE in tumorigenesis. Acta Pharmacol Sin 2013; 34:991-7. [PMID: 23770988 PMCID: PMC3733165 DOI: 10.1038/aps.2013.71] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2013] [Accepted: 04/28/2013] [Indexed: 01/22/2023] Open
Abstract
Tumorigenesis is the process by which normal cells evolve the capacity to evade and overcome the constraints usually placed upon their growth and survival. To ensure the integrity of organs and tissues, the balance of cell proliferation and cell death is tightly maintained. The proteins controlling this balance are either considered oncogenes, which promote tumorigenesis, or tumor suppressors, which prevent tumorigenesis. Phosphoinositide 3-kinase enhancer (PIKE) is a family of GTP-binding proteins that possess anti-apoptotic functions and play an important role in the central nervous system. Notably, accumulating evidence suggests that PIKE is a proto-oncogene involved in tumor progression. The PIKE gene (CENTG1) is amplified in a variety of human cancers, leading to the resistance against apoptosis and the enhancement of invasion. In this review, we will summarize the functions of PIKE proteins in tumorigenesis and discuss their potential implications in cancer therapy.
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Erovic BM, Kim D, Cassol C, Goldstein DP, Irish JC, Asa SL, Mete O. Prognostic and predictive markers in medullary thyroid carcinoma. Endocr Pathol 2012; 23:232-42. [PMID: 23150029 DOI: 10.1007/s12022-012-9225-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Unlike papillary thyroid carcinoma, medullary thyroid carcinoma is insensitive to adjuvant treatment with radioactive iodine. The clinical management of patients with advanced or metastatic disease remains challenging since no effective systemic adjuvant therapy is available. We aimed to identify markers of aggressive disease and novel drugable protein targets that would provide systemic adjuvant treatment for patients with advanced medullary thyroid carcinoma. We therefore examined morphologic features of aggressive behavior and the expression of 41 proteins involved in apoptosis, cell cycle, angiogenesis, inflammation, cell adhesion, tumor-specific markers, and WNT, SHH, and AKT pathways using tissue microarray from 23 patients with medullary thyroid carcinoma. Protein expression was determined using computerized image analysis software. Statistical analysis was carried out to correlate clinical data with the average score for each marker. Angioinvasion proved to be the most reliable predictor of disease recurrence and death. The rate of angioinvasion was 43 %. All angioinvasive medullary thyroid carcinomas had locoregional and/or distant metastasis; 60 % of angioinvasive medullary thyroid carcinomas developed distant metastasis. We identified expression of several potentially important protein targets such as COX-1/2, Bcl-2a, Gst-π, Gli-1, Gli-2, Gli-3, and Bmi-1 that may be therapeutically targeted in medullary thyroid carcinoma. More importantly, the immunohistochemical profile of SSTRs in medullary thyroid carcinoma may also have clinical relevance for the administration of peptide receptor radionuclide treatment. Successful outcome of clinical trials directed against these novel targets would provide much needed systemic adjuvant treatment for patients with advanced medullary thyroid carcinoma, and our data suggest the possibility of stratifying patients who are likely to require adjuvant therapy before their burden of disease precludes successful therapeutic effect.
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Affiliation(s)
- Boban M Erovic
- Department of Otolaryngology-Head and Neck Surgery/Surgical Oncology, University Health Network, Toronto, ON, Canada
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Tong X, Lan W, Zhang X, Wu H, Liu M, Cao C. Solution structure of all parallel G-quadruplex formed by the oncogene RET promoter sequence. Nucleic Acids Res 2011; 39:6753-63. [PMID: 21540209 PMCID: PMC3159441 DOI: 10.1093/nar/gkr233] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2011] [Revised: 04/03/2011] [Accepted: 04/04/2011] [Indexed: 11/12/2022] Open
Abstract
RET protein functions as a receptor-type tyrosine kinase and has been found to be aberrantly expressed in a wide range of human diseases. A highly GC-rich region upstream of the promoter plays an important role in the transcriptional regulation of RET. Here, we report the NMR solution structure of the major intramolecular G-quadruplex formed on the G-rich strand of this region in K(+) solution. The overall G-quadruplex is composed of three stacked G-tetrad and four syn guanines, which shows distinct features for all parallel-stranded folding topology. The core structure contains one G-tetrad with all syn guanines and two other with all anti-guanines. There are three double-chain reversal loops: the first and the third loops are made of 3 nt G-C-G segments, while the second one contains only 1 nt C10. These loops interact with the core G-tetrads in a specific way that defines and stabilizes the overall G-quadruplex structure and their conformations are in accord with the experimental mutations. The distinct RET promoter G-quadruplex structure suggests that it can be specifically involved in gene regulation and can be an attractive target for pathway-specific drug design.
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Affiliation(s)
- Xiaotian Tong
- State Key Laboratory of Bio-organic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032 and State Kay Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - Wenxian Lan
- State Key Laboratory of Bio-organic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032 and State Kay Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - Xu Zhang
- State Key Laboratory of Bio-organic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032 and State Kay Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - Houming Wu
- State Key Laboratory of Bio-organic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032 and State Kay Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - Maili Liu
- State Key Laboratory of Bio-organic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032 and State Kay Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - Chunyang Cao
- State Key Laboratory of Bio-organic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032 and State Kay Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
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Abstract
Uterine leiomyomas (fibroids, myomas) are benign tumors that develop from smooth muscle cells. Although the most common gynecologic tumor in premenopausal women, there is still little known of the etiology, the genetics and basic/molecular biology, or the influence of the environment on the development and growth of these tumors. The fact that fibroids occur during the reproductive years and regress after menopause indicates a growth dependent on ovarian hormones. Studies have supported a role of estrogen and progesterone in leiomyoma growth possibly through regulating growth factors and their signaling pathways. Activation of steroid hormone receptors can have a myriad of effects and include upregulation of growth factors and receptor tyrosine kinases (RTKs), which through downstream effector proteins such as mitogen-activated protein kinase p44/42, can mediate transcription, translation, and cell proliferation. Due to their hormonal dependency, fibroids may also be targeted by environmental chemicals whose biological effects are mediated through the estrogen and/or progesterone receptors. This review focuses on the role of growth factors and their receptors (RTKs) in uterine leiomyoma growth and their regulation by ovarian hormones. It also presents data on specific signaling pathways activated in uterine leiomyomas and the "cross talk" between the estrogen receptor alpha and RTK signaling pathways.
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Affiliation(s)
- Linda Yu
- Cellular and Molecular Pathology Branch (CMPB), National Toxicology Program, National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Research Triangle Park, North Carolina
| | - Alicia B. Moore
- Cellular and Molecular Pathology Branch (CMPB), National Toxicology Program, National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Research Triangle Park, North Carolina
| | - Darlene Dixon
- Cellular and Molecular Pathology Branch (CMPB), National Toxicology Program, National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Research Triangle Park, North Carolina
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PET imaging of medullary thyroid carcinoma in MEN2A transgenic mice using 6-[(18)F]F-L-DOPA. Eur J Nucl Med Mol Imaging 2010; 37:58-66. [PMID: 19655139 DOI: 10.1007/s00259-009-1208-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2009] [Accepted: 06/07/2009] [Indexed: 10/20/2022]
Abstract
PURPOSE 6-[(18)F]Fluoro-3,4-dihydroxy-L-phenylalanine (6-[(18)F]F-L-DOPA) is increasingly used for PET imaging of neuroendocrine tumours. In this study, we investigated the use of 6-[(18)F]F-L-DOPA to detect and to monitor the progression of medullary thyroid carcinoma (MTC) in a genetically engineered mouse model of multiple endocrine neoplasia type 2A (MEN2A). METHODS Dynamic [(18)F]FDG and 6-[(18)F]F-L-DOPA small animal PET scans were acquired during 60 or 90 min in 8- to 20-month-old MEN2A transgenic mice. The kinetics of 6-[(18)F]F-L-DOPA, standardized uptake values (SUV) at 60 min and tumour volumes were recorded. The detection of MTCs using PET was confirmed by autopsy and histological analysis. RESULTS 6-[(18)F]F-L-DOPA performs better than [(18)F]FDG for MTC detection in this transgenic mouse model. Uptake kinetics of 6-[(18)F]F-L-DOPA in MTCs are very different between mice but, in all cases, high contrast could be observed. Furthermore, 6-[(18)F]F-L-DOPA can detect tumours with sizes (1.8 mm(3)) that are near the resolution limit of PET, whereas they were undetectable by autopsy at the macroscopic level. CONCLUSION 6-[(18)F]F-L-DOPA PET imaging can monitor the progression of MTCs in a genetically engineered mouse model.
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van Veelen W, de Groot JWB, Acton DS, Hofstra RMW, Höppener JWM, Links TP, Lips CJM. Medullary thyroid carcinoma and biomarkers: past, present and future. J Intern Med 2009; 266:126-40. [PMID: 19522831 DOI: 10.1111/j.1365-2796.2009.02106.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The clinical management of patients with persistent or recurrent medullary thyroid carcinoma (MTC) is still under debate, because these patients either have a long-term survival, due to an indolent course of the disease, or develop rapidly progressing disease leading to death from distant metastases. At this moment, it cannot be predicted what will happen within most individual cases. Biomarkers, indicators which can be measured objectively, can be helpful in MTC diagnosis, molecular imaging and treatment, and/or identification of MTC progression. Several MTC biomarkers are already implemented in the daily management of MTC patients. More research is being aimed at the improvement of molecular imaging techniques and the development of molecular systemic therapies. Recent discoveries, like the prognostic value of plasma calcitonin and carcino-embryonic antigen doubling-time and the presence of somatic RET mutations in MTC tissue, may be useful tools in clinical decision making in the future. In this review, we provide an overview of different MTC biomarkers and their applications in the clinical management of MTC patients.
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Affiliation(s)
- W van Veelen
- The Division of Biomedical Genetics, Department of Metabolic and Endocrine Diseases, University Medical Centre Utrecht, Utrecht.
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17
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Uetani N, Bertozzi K, Chagnon MJ, Hendriks W, Tremblay ML, Bouchard M. Maturation of ureter-bladder connection in mice is controlled by LAR family receptor protein tyrosine phosphatases. J Clin Invest 2009; 119:924-35. [PMID: 19273906 DOI: 10.1172/jci37196] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2008] [Accepted: 01/21/2009] [Indexed: 01/13/2023] Open
Abstract
Congenital anomalies affecting the ureter-bladder junction are frequent in newborns and are often associated with other developmental defects. However, the molecular and morphological processes underlying these malformations are still poorly defined. In this study, we identified the leukocyte antigen-related (LAR) family protein tyrosine phosphatase, receptor type, S and F (Ptprs and Ptprf [also known as Lar], respectively), as crucially important for distal ureter maturation and craniofacial morphogenesis in the mouse. Embryos lacking both Ptprs and Ptprf displayed severe urogenital malformations, characterized by hydroureter and ureterocele, and craniofacial defects such as cleft palate, micrognathia, and exencephaly. The detailed analysis of distal ureter maturation, the process by which the ureter is displaced toward its final position in the bladder wall, leads us to propose a revised model of ureter maturation in normal embryos. This process was deficient in embryos lacking Ptprs and Ptprf as a result of a marked reduction in intrinsic programmed cell death, thereby causing urogenital system malformations. In cell culture, Ptprs bound and negatively regulated the phosphorylation and signaling of the Ret receptor tyrosine kinase, whereas Ptprs-induced apoptosis was inhibited by Ret expression. Together, these results suggest that ureter positioning is controlled by the opposing actions of Ret and LAR family phosphatases regulating apoptosis-mediated tissue morphogenesis.
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Affiliation(s)
- Noriko Uetani
- Goodman Cancer Centre, Department of Biochemistry, McGill University, Montreal, Quebec, Canada
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Cerchia L, Giangrande PH, McNamara JO, de Franciscis V. Cell-specific aptamers for targeted therapies. Methods Mol Biol 2009; 535:59-78. [PMID: 19377980 DOI: 10.1007/978-1-59745-557-2_5] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Many signalling proteins involved in diverse functions such as cell growth and differentiation can act as oncogenes and cause cellular transformation. These molecules represent attractive targets for cancer diagnosis or therapy and therefore are subject to intensive investigation. Aptamers are small, highly structured nucleic acid molecules, isolated from combinatorial libraries by a procedure termed SELEX. Aptamers bind to a target molecule by providing a limited number of specific contact points imbedded in a larger, defined three-dimensional structure. Recently, aptamers have been selected against whole living cells, opening a new path which presents three major advantages: (1) direct selection without prior purification of membrane-bound targets, (2) access to membrane proteins in their native conformation similar to the in vivo conditions and (3) identification of (new) targets related to a specific phenotype. The ability to raise aptamers against living cells opens some attractive possibilities for new therapeutic and delivery approaches. In this chapter, the most recent advances in the field will be reviewed together with detailed descriptions of the relevant experimental approaches.
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Affiliation(s)
- Laura Cerchia
- Istituto per l'Endocrinologia e Oncologia Sperimentale G. Salvatore, Naples, Italy
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Fazioli F, Piccinini G, Appolloni G, Bacchiocchi R, Palmonella G, Recchioni R, Pierpaoli E, Silvetti F, Scarpelli M, Bruglia M, Melillo RM, Santoro M, Boscaro M, Taccaliti A. A new germline point mutation in Ret exon 8 (cys515ser) in a family with medullary thyroid carcinoma. Thyroid 2008; 18:775-82. [PMID: 18631007 DOI: 10.1089/thy.2007.0365] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND A novel Cys-Ser Ret germline point mutation in a 58-year-old woman with bilateral medullary thyroid carcinoma (MTC) prompted us to perform genetic analysis of the family and evaluate the biological consequences of such a mutation. METHODS Ret analysis by direct sequencing was performed in five family members. The biological activity and biochemical properties of the Ret- Cys515Ser mutant were analyzed in NIH-3T3 cells. RESULTS The proband's son, age 35, had the Ret- Cys515Ser mutation and the L769 CTT/CTG exon 13 polymorphic variant, which was also found in his father. Clinical evaluation of the son also revealed bilateral multifocal microscopic MTC and papillary thyroid carcinoma (PTC). In vitro and in vivo analysis indicated ligand-independent activation of the Ret-Cys515Ser mutant due to aberrant disulfide homodimerization, increased mitogenic activity, and ability to induce anchorage-independent growth in NIH-3T3 cells in comparison to wild-type Ret, suggesting a possible role of Cys515Ser in tumor development. CONCLUSIONS The Cys515Ser mutation adds to cysteine substitution groups that have been described in association with MTC. Our data also highlight the importance of performing a complete genetic analysis in patients who present with MTC.
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Affiliation(s)
- Francesca Fazioli
- Laboratory of Cellular and Molecular Biology, Department of Molecular Pathology and Innovative Therapies, Polytechnic University of the Marche Region, Ancona, Italy.
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20
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Guo K, Pourpak A, Beetz-Rogers K, Gokhale V, Sun D, Hurley LH. Formation of pseudosymmetrical G-quadruplex and i-motif structures in the proximal promoter region of the RET oncogene. J Am Chem Soc 2007; 129:10220-8. [PMID: 17672459 PMCID: PMC2566970 DOI: 10.1021/ja072185g] [Citation(s) in RCA: 214] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A polypurine (guanine)/polypyrimidine (cytosine)-rich sequence within the proximal promoter region of the human RET oncogene has been shown to be essential for RET basal transcription. Specifically, the G-rich strand within this region consists of five consecutive runs of guanines, which is consistent with the general motif capable of forming intramolecular G-quadruplexes. Here we demonstrate that, in the presence of 100 mM K+, this G-rich strand has the ability to adopt two intramolecular G-quadruplex structures in vitro. Moreover, comparative circular dichroism (CD) and DMS footprinting studies have revealed that the 3'-G-quadruplex structure is a parallel-type intramolecular structure containing three G-tetrads. The G-quadruplex-interactive agents TMPyP4 and telomestatin further stabilize this G-quadruplex structure. In addition, we demonstrate that the complementary C-rich strand forms an i-motif structure in vitro, as shown by CD spectroscopy and chemical footprinting. This 19-mer duplex sequence is predicted to form stable intramolecular G-quadruplex and i-motif species having minimum symmetrical loop sizes of 1:3:1 and 2:3:2, respectively. Together, our results indicate that stable G-quadruplex and i-motif structures can form within the proximal promoter region of the human RET oncogene, suggesting that these secondary structures play an important role in transcriptional regulation of this gene.
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Affiliation(s)
- Kexiao Guo
- Department of Biochemistry and Molecular Biophysics, University of Arizona, Tucson, Arizona 85721
| | - Alan Pourpak
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, Arizona 85724
| | - Kara Beetz-Rogers
- Department of Pharmacology, College of Medicine, University of Arizona, Tucson, Arizona 85724
| | - Vijay Gokhale
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona 85721
| | - Daekyu Sun
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona 85721
- Address correspondence to either author, Telephone: (520) 626-5622, FAX: (520) 626-5623, ,
| | - Laurence H. Hurley
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona 85721
- Arizona Cancer Center, 1515 N. Campbell Ave., Tucson, Arizona 85724
- BIO5 Collaborative Research Institute, 1657 E. Helen Street, Tucson, Arizona 85719
- Address correspondence to either author, Telephone: (520) 626-5622, FAX: (520) 626-5623, ,
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Messina M, Robinson BG. Technology insight: gene therapy and its potential role in the treatment of medullary thyroid carcinoma. ACTA ACUST UNITED AC 2007; 3:290-301. [PMID: 17315037 DOI: 10.1038/ncpendmet0420] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2006] [Accepted: 11/01/2006] [Indexed: 12/25/2022]
Abstract
Metastatic medullary thyroid cancer (MTC) responds poorly to conventional treatments with chemotherapy and radiotherapy. Gene therapy--the transfer of genetic material for therapeutic purposes--might have therapeutic potential for patients with progressive metastatic MTC that is incurable by conventional treatments. To date, a number of gene-therapy strategies have been explored, primarily those that use replication-deficient adenovirus vectors to transfer therapeutic genes to tumor cells. Tissue-specific expression of the promoter for calcitonin and calcitonin-related polypeptide alpha has allowed therapeutic genes to be specifically expressed in calcitonin-secreting cells and in the MTC tumors derived from them; such tissue-specific expression contributes to improved safety of gene therapies and has the potential to increase their therapeutic index. In addition, the identification of an MTC-specific peptide ligand raises the possibility of developing an MTC-selective vector. In this article, we have described the exciting area of gene therapy in the management of MTC with a focus on preclinical in vitro and in vivo MTC models.
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Affiliation(s)
- Marinella Messina
- Cancer Genetics Unit of Kolling Institute of Medical Research, Royal North Shore Hospital, St Leonards, New South Wales, Australia.
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Drosten M, Pützer BM. Mechanisms of Disease: cancer targeting and the impact of oncogenic RET for medullary thyroid carcinoma therapy. ACTA ACUST UNITED AC 2006; 3:564-74. [PMID: 17019434 DOI: 10.1038/ncponc0610] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2006] [Accepted: 05/22/2006] [Indexed: 12/11/2022]
Abstract
Growing evidence supports the concept of oncogene dependence for cancer development; inhibition of the initiating oncogene can result in revertion of the neoplastic phenotype. The outstanding role of the RET proto-oncogene in the development of medullary thyroid carcinoma (MTC) is well established. With the emerging knowledge concerning the signal transduction pathways leading to subsequent neoplastic transformation, oncogenic activated RET becomes a highly attractive target for selective cancer therapy. A variety of novel approaches that target RET directly or indirectly have recently emerged and an increasing number are currently being assessed in clinical trials. In view of these findings, it becomes strikingly obvious that inhibition of RET oncogene function can be a viable option for the treatment of MTC. We summarize the current evidence for RET involvement in the etiology of MTC, and the therapeutic targeting of this process in preclinical and clinical studies.
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Affiliation(s)
- Matthias Drosten
- Department of Vectorology and Experimental Gene Therapy, Biomedical Research Centre, University of Rostock, Schillingallee 70, 18057 Rostock, Germany
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de Groot JWB, Links TP, Plukker JTM, Lips CJM, Hofstra RMW. RET as a diagnostic and therapeutic target in sporadic and hereditary endocrine tumors. Endocr Rev 2006; 27:535-60. [PMID: 16849421 DOI: 10.1210/er.2006-0017] [Citation(s) in RCA: 228] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The RET gene encodes a receptor tyrosine kinase that is expressed in neural crest-derived cell lineages. The RET receptor plays a crucial role in regulating cell proliferation, migration, differentiation, and survival through embryogenesis. Activating mutations in RET lead to the development of several inherited and noninherited diseases. Germline point mutations are found in the cancer syndromes multiple endocrine neoplasia (MEN) type 2, including MEN 2A and 2B, and familial medullary thyroid carcinoma. These syndromes are autosomal dominantly inherited. The identification of mutations associated with these syndromes has led to genetic testing to identify patients at risk for MEN 2 and familial medullary thyroid carcinoma and subsequent implementation of prophylactic thyroidectomy in mutation carriers. In addition, more than 10 somatic rearrangements of RET have been identified from papillary thyroid carcinomas. These mutations, as those found in MEN 2, induce oncogenic activation of the RET tyrosine kinase domain via different mechanisms, making RET an excellent candidate for the design of molecular targeted therapy. Recently, various kinds of therapeutic approaches, such as tyrosine kinase inhibition, gene therapy with dominant negative RET mutants, monoclonal antibodies against oncogene products, and nuclease-resistant aptamers that recognize and inhibit RET have been developed. The use of these strategies in preclinical models has provided evidence that RET is indeed a potential target for selective cancer therapy. However, a clinically useful therapeutic option for treating patients with RET-associated cancer is still not available.
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Affiliation(s)
- Jan Willem B de Groot
- Department of Endocrinology, University Medical Center Groningen, University of Groningen, The Netherlands
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Petrangolini G, Cuccuru G, Lanzi C, Tortoreto M, Belluco S, Pratesi G, Cassinelli G, Zunino F. Apoptotic cell death induction and angiogenesis inhibition in large established medullary thyroid carcinoma xenografts by Ret inhibitor RPI-1. Biochem Pharmacol 2006; 72:405-14. [PMID: 16756963 DOI: 10.1016/j.bcp.2006.05.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2006] [Revised: 04/28/2006] [Accepted: 05/01/2006] [Indexed: 11/15/2022]
Abstract
Recent evidence indicates that the success of molecular targeted therapies may depend on the identification of drug targets which are essential for the survival of subsets of tumors. RET oncogenes that have been implicated in the development of thyroid carcinomas are emerging as potential therapeutic targets. In the present study, we investigated the efficacy and the cellular bases of antitumor activity of the indolinone Ret tyrosine kinase inhibitor RPI-1 against large established s.c. TT tumor xenograft, a human medullary thyroid carcinoma (MTC) harboring oncogenic MEN-2A-type RET mutation. Oral treatment with RPI-1 caused growth arrest or regression in 81% treated tumors. Following treatment suspension, tumor inhibition was maintained (51%, P<0.05, 100 days) and cures were achieved in 2/11 mice. In treated tumors, Ret was tyrosine dephosphorylated. Moreover, compared to control tumors, a significant increase in apoptotic cells (210%, P<0.0001), loss of cellularity (47%, P<0.0001) and reduction of microvessel density (36%, P<0.0005) were detected. In vivo effects of RPI-1 were reflected in activation of BAD, cleavage of caspases, apoptotic DNA fragmentation and inhibition of VEGF production observed in in vitro RPI-1-treated TT cells. These findings thus indicate that RPI-1 antitumor effect on the MTC was characterized by apoptosis induction and angiogenesis inhibition. The results, consistent with a dependence on RET oncogene activation for maintenance and survival of MEN2A-type MTC, provide further preclinical rationale for a pharmacological RET-targeted intervention in thyroid cancer.
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Affiliation(s)
- Giovanna Petrangolini
- Department of Experimental Oncology and Laboratories, Istituto Nazionale Tumori, Via Venezian 1, 20133 Milan, Italy
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Lachinski AJ, Stefaniak T, Kobiela J, Connor S, Gruca Z, Sledzinski Z. New prognostic scales LAST-1 and LAST-2: supporting prediction and staging of thyroid cancer. World J Surg 2006; 30:309-20. [PMID: 16479347 DOI: 10.1007/s00268-005-0277-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
INTRODUCTION Epidemiologically, thyroid gland tumors are lesions of the highest importance among endocrine tumors in humans. Although the results of surgical treatment of the highly differentiated (follicular and papillary) tumors seem to be satisfactory, treatment of the poorly differentiated (medullary and anaplastic) tumor still demands clinical and basic investigations. In this study the authors sought to evaluate clinical and molecular factors that could contribute to preoperative detection of more advanced thyroid cancers (i.e., those that exhibit extrathyroid spread and lymph node invasion). METHODS A total of 27 patients operated on for thyroid cancer were evaluated according to age, sex, time from the onset of the disease, cytogenetic changes, and loss of heterozygosity (LOH) in 14 microsatellite markers. The output variables were defined according to postoperative findings and the TNM 2002 score. The T1-2 N0 M0 cases were defined as local malignancy (LM); and T3-4 any N any M, any T N1 any M, or any T any N M1 were considered advanced malignancy (AM). The control groups consisted of 25 patients with multinodular goiter (MNG) and 32 patients with follicular adenoma (FA). In all cases, clinical and molecular data similar to those listed above were collected, excluding staging and follow-up information. RESULTS There was no predominant specific type of chromosomal aberration observed and no marker lost in more than five patients (18%). The logistic regression identified three input variables as contributing significantly to the dichotomized outcome measure (LM vs. AM): LOH in any of the examined loci, age of the patient at the presentation, and the sex of the patient. Furthermore, discriminant analysis revealed four input variables differentiating among TC, FA, and MNG patients. Based on the multivariate analysis results, two numeric prognostic scales were fashioned: LAST-1, a scale applicable to differentiation of thyroid cancers at different degrees of clinical advancement; and LAST-2, a scale applicable to differentiation of any thyroid lumps. CONCLUSIONS It was concluded that LOH and the age and sex of the patients can provide sufficient data to predict thyroid cancer with a high degree of clinical advancement. LAST-1 scale is a reliable tool for identifying these patients. The LAST-2 scale gives supportive information about the character of thyroid lumps, distinguishing TC from MNG and FA.
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Affiliation(s)
- Andrzej J Lachinski
- Department of General, Endocrine and Transplant Surgery, Medical University of Gdansk, 1 Debinki Street, Gdansk, PL, 80-211, Poland.
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Blagosklonny MV. Overcoming limitations of natural anticancer drugs by combining with artificial agents. Trends Pharmacol Sci 2005; 26:77-81. [PMID: 15681024 DOI: 10.1016/j.tips.2004.12.002] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
During a billion years of evolution, living creatures have perfected cytotoxic agents to kill other organisms without killing themselves, thus providing us with antibiotics to kill bacteria without killing eukaryotic (e.g. human) cells. Some natural agents inhibit specifically most vital cellular structures and functions in cancer cells. However, nature was not creating antibiotics for cancer, and natural agents kill cancer cells precisely because they share targets with normal cells. To discriminate between particular cancer cells and normal cells, we can design or select artificial agents that are not necessarily lethal but are aimed either at cancer-specific targets or at dispensable and even unavailable (in cancer cells) targets. Using rational drug combinations, such selective agents can assist natural agents to eradicate cancer cells selectively.
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Affiliation(s)
- Mikhail V Blagosklonny
- Brander Cancer Research Institute, New York Medical College, 19 Bradhurst Avenue, Hawthorne, NY 10532, USA.
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Böckmann M, Hilken G, Schmidt A, Cranston AN, Tannapfel A, Drosten M, Frilling A, Ponder BAJ, Pützer BM. Novel SRESPHP Peptide Mediates Specific Binding to Primary Medullary Thyroid Carcinoma After Systemic Injection. Hum Gene Ther 2005; 16:1267-75. [PMID: 16259560 DOI: 10.1089/hum.2005.16.1267] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The efficient and specific introduction of genes into cancer cells in vivo remains a major challenge for current gene therapy modalities. Peptides possess appropriate properties to serve as tumor-targeting agents. Thus, finding new cancer-selective peptides directing gene transfer to neoplastic cells by reducing transduction of normal cells is a central goal for molecular targeting. We have previously reported identification of a peptide (HTFEPGV) that selectively binds to human medullary thyroid carcinoma (MTC)-derived TT cells in vitro and transplanted tumor xenografts in vivo, using phage display. In the present study, we have performed this approach in primary orthotopically growing murine MTCs of RET-C634R transgenic mice as a clinically relevant model for thyroid cancer by intravenous injection of a complex peptide library. Two rounds of screening on primary tumors yielded multiple copies of a phage that displays a cyclic 7-amino acid peptide, SRESPHP, with a 3000-fold increase in titer between rounds 1 and 2. The selected phage showed highly specific binding to the tumor after systemic administration, whereas binding to other organs such as lung, liver, kidney, and heart was reduced up to 90%. After tail vein injection, homing to the tumor was substantially reduced in the presence of synthetic SRESPHP peptide, indicating that tumor phage interaction strictly depends on the displayed peptide. Immunohistochemical analysis of paraffin sections from mouse tissues revealed direct binding of the SRESPHP peptide to MTC tissue. Moreover, this peptide also mediates binding to human MTC cells in vitro and in vivo, suggesting abundant expression of its cognate receptor in murine and human medullary thyroid carcinoma. Because the SRESPHP peptide is also efficiently internalized into MTC cells, it likely provides the basis for a new selective therapy of medullary thyroid carcinoma.
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Affiliation(s)
- Miriam Böckmann
- Department of Vectorology and Experimental Gene Therapy, University of Rostock Medical School, 18055 Rostock, Germany
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Bockmann M, Hilken G, Schmidt A, Cranston AN, Tannapfel A, Drosten M, Frilling A, Ponder BA, Putzer BM. Novel SRESPHP Peptide Mediates Specific Binding to Primary Medullary Thyroid Carcinoma After Systemic Injection. Hum Gene Ther 2005. [DOI: 10.1089/hum.2005.16.ft-135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Musholt TJ, Hanack J, Brehm C, von Wasielewski R, Musholt PB. Searching for non-RET molecular alterations in medullary thyroid carcinoma: expression analysis by mRNA differential display. World J Surg 2005; 29:472-82. [PMID: 15776290 DOI: 10.1007/s00268-004-7748-y] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Some 25%-70% of sporadic medullary thyroid carcinomas (MTCs) are associated with somatic mutations within the RET proto-oncogene. In a significant number of MTCs, however, no such genetic variations can be detected, which implies alternative pathogenic molecular alterations. To assess altered RET mutation-specific gene expression, and to identify yet unknown gene transcripts involved in the tumorigenesis of MTC, we performed an expression analysis by mRNA differential display (RT-DD). Snap-frozen tumor tissues and corresponding normal thyroid tissues of 8 patients suffering from MTC (6 sporadic, 2 hereditary tumors) were included in the study; 5/8 MTCs harbored RET point mutations (codons 618, 634, 918). The RT-DD method was refined by use of fluorescence-labeled arbitrary oligonucleotides, electrophoresis on an automated sequencer, and a novel fragment-recovery technique utilizing a high-performance fluorescence scanner. More than 400 differentially expressed mRNA transcripts--representing upregulated or downregulated genes in the compared tissues--were detected. In all, 28 selected fragments were recovered, cloned, sequenced, and identified. Differential expression of gene transcripts with known association to cell proliferation or tumor progression--such as annexin A2, Rab11a, trefoil proteins, superoxide dismutase (SOD1), mitochondrial displacement loop (D-loop), and G protein subunit gamma11--as well as of the neuroendocrine marker chromogranin was observed. Furthermore, several mRNA transcripts of yet unknown genes displayed mutation-specific upregulation or downregulation in MTC. Illumination of the molecular basis especially of C-cell carcinomas without detectable alterations of the RET receptor tyrosine kinase will be required for the development of therapeutic strategies for advanced tumors that cannot be bridled or cured by surgical interventions alone.
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Affiliation(s)
- Thomas J Musholt
- Department of General and Abdominal Surgery, Johannes Gutenberg University, Langenbeckstr.1, 55101 Mainz, Germany.
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Cerchia L, Ducongé F, Pestourie C, Boulay J, Aissouni Y, Gombert K, Tavitian B, de Franciscis V, Libri D. Neutralizing aptamers from whole-cell SELEX inhibit the RET receptor tyrosine kinase. PLoS Biol 2005; 3:e123. [PMID: 15769183 PMCID: PMC1065267 DOI: 10.1371/journal.pbio.0030123] [Citation(s) in RCA: 200] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2004] [Accepted: 02/02/2005] [Indexed: 11/19/2022] Open
Abstract
Targeting large transmembrane molecules, including receptor tyrosine kinases, is a major pharmacological challenge. Specific oligonucleotide ligands (aptamers) can be generated for a variety of targets through the iterative evolution of a random pool of sequences (SELEX). Nuclease-resistant aptamers that recognize the human receptor tyrosine kinase RET were obtained using RET-expressing cells as targets in a modified SELEX procedure. Remarkably, one of these aptamers blocked RET-dependent intracellular signaling pathways by interfering with receptor dimerization when the latter was induced by the physiological ligand or by an activating mutation. This strategy is generally applicable to transmembrane receptors and opens the way to targeting other members of this class of proteins that are of major biomedical importance. The strategy used to select aptamers that bind a tyrosine kinase mutated in certain cancers holds promise for targeting other members of this biomedically important class of proteins.
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Affiliation(s)
- Laura Cerchia
- Istituto per I'Endocrinologia e Oncologia Molecolare “G. Salvatore”, CNR, Naples, Italy
| | - Frédéric Ducongé
- CEA/DSV/DRM Service Hospitalier Frédéric Joliot, INSERM E-103, Orsay, France
| | - Carine Pestourie
- CEA/DSV/DRM Service Hospitalier Frédéric Joliot, INSERM E-103, Orsay, France
| | - Jocelyne Boulay
- Centre de Génétique Moléculaire, Centre National de la Recherche Scientifique (CNRS), Gif sur Yvette, France
| | - Youssef Aissouni
- Centre de Génétique Moléculaire, Centre National de la Recherche Scientifique (CNRS), Gif sur Yvette, France
| | - Karine Gombert
- CEA/DSV/DRM Service Hospitalier Frédéric Joliot, INSERM E-103, Orsay, France
| | - Bertrand Tavitian
- CEA/DSV/DRM Service Hospitalier Frédéric Joliot, INSERM E-103, Orsay, France
- * To whom correspondence should be addressed. E-mail: (BT), (VD)
| | - Vittorio de Franciscis
- Istituto per I'Endocrinologia e Oncologia Molecolare “G. Salvatore”, CNR, Naples, Italy
- * To whom correspondence should be addressed. E-mail: (BT), (VD)
| | - Domenico Libri
- Centre de Génétique Moléculaire, Centre National de la Recherche Scientifique (CNRS), Gif sur Yvette, France
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Kodama Y, Asai N, Kawai K, Jijiwa M, Murakumo Y, Ichihara M, Takahashi M. The RET proto-oncogene: a molecular therapeutic target in thyroid cancer. Cancer Sci 2005; 96:143-8. [PMID: 15771616 PMCID: PMC11159891 DOI: 10.1111/j.1349-7006.2005.00023.x] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The RET proto-oncogene is responsible for the development of several human inherited and non-inherited diseases. Germline point mutations were identified in multiple endocrine neoplasia types 2A and 2B, and familial medullary thyroid carcinoma. More than 10 rearranged forms of RET, referred to as RET/PTC 1-9, ELKS/RET and RFP/RET, have been cloned from sporadic and radiation-associated papillary thyroid carcinomas. These mutations induced oncogenic activation of RET tyrosine kinase by different mechanisms. To date, various kinds of therapeutic approaches have been developed for the treatment of RET-associated cancers, including tyrosine kinase inhibitors, gene therapy with dominant negative RET mutants, and RNA interference to abrogate oncogenic mutant RET expression. RET and some signaling molecules that function downstream of RET could be potential targets for the development of selective cancer therapeutics.
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Affiliation(s)
- Yoshinori Kodama
- Department of Pathology, Center for Neurological Disease and Cancer, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho Showa-ku Nagoya, 466-8550, Japan
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