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Li Y, Qin G, Du J, Yue P, Zhang Y, Hou N. circRNA LDLRAD3 Enhances the Malignant Behaviors of NSCLC Cells via the miR-20a-5p-SLC7A5 Axis Activating the mTORC1 Signaling Pathway. JOURNAL OF HEALTHCARE ENGINEERING 2022; 2022:2373580. [PMID: 35035814 PMCID: PMC8758255 DOI: 10.1155/2022/2373580] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 12/02/2021] [Accepted: 12/03/2021] [Indexed: 12/12/2022]
Abstract
Circular RNA LDLRAD3 behaved as an oncogene in several malignancies, but its effects in NSCLC and the involvement of downstream molecules and activation of signaling pathways had not been fully reported. We planned to explore how LDLRAD3 facilitated the malignancy of NSCLC. QRT-PCR was performed to evaluate the expression levels of LDLRAD3, miR-20a-5p, and SLC7A5 in NSCLC tissues and cells. si-LDLRAD3 was transfected to A549 and H1299 cells to knock down intrinsic LDLRAD3 to determine its oncogenic roles. CCK-8 assay and transwell assay were executed to assess cell proliferative, migrative, and invasive abilities. Dual-luciferase reporter (DLR) assay was manipulated to verify the ENCORI-predicted relationships between LDLRAD3 and miR-20a-5p and between miR-20a-5p and SLC7A5. Western blot, immunofluorescent assay, and immunohistochemistry were applied to explore the expression levels of SLC7A5, and the levels of mTORC1 pathway-related proteins were evaluated using western blot. Rescue experiments were conducted by transfecting si-LDLRAD3, miR-20a-5p inhibitor, and si-SLC7A5 to explore the influence of the LDLRAD3-miR-20a-5p-SLC7A5 axis on the malignant behaviors of NSCLC cells. The expression levels of LDLRAD3 and SLC7A5 were boosted, whereas miR-20a-5p was impeded in NSCLC tissues and cell lines. Knockdown of LDLRAD3 weakened the proliferation, migration, and invasion of A549 and H1299 cells. LDLRAD3 was verified to sponge miR-20a-5p and miR-20a-5p targeted SLC7A5. LDLRAD3 activated the mTORC1 singling pathway via the miR-20a-5p-SLC7A5 axis to strengthen the malignant properties of A549 and H1299 cells. We concluded that LDLRAD3 exerted oncogenic effects via the miR-20a-5p-SLC7A5 axis to activate the mTORC1 signaling pathway in NSCLC. Our findings enlightened that LDLRAD3 could become a potential therapeutic target in the treatment and management of NSCLC.
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Affiliation(s)
- Yu Li
- Department of ICU Medicine, Shandong Province Zibo No. 1 Hospital, Zibo 255200, Shandong, China
| | - Guangle Qin
- Emergency Department, Shandong Province Zibo No. 1 Hospital, Zibo 255200, Shandong, China
| | - Jinyun Du
- Department of ICU Medicine, Shandong Province Zibo No. 1 Hospital, Zibo 255200, Shandong, China
| | - Peng Yue
- Emergency Department, Shandong Province Zibo No. 1 Hospital, Zibo 255200, Shandong, China
| | - Yanling Zhang
- Department of Intensive Care, Boxing County Hospital of Traditional Chinese Medicine, Binzhou 256500, Shandong, China
| | - Na Hou
- Oncology Dept. II, Shandong Province Zibo No. 1 Hospital, Zibo 255200, Shandong, China
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2
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Shaikh S, Yadav DK, Rawal R. Saliva based non invasive screening of Oral Submucous Fibrosis using ATR-FTIR spectroscopy. J Pharm Biomed Anal 2021; 203:114202. [PMID: 34130007 DOI: 10.1016/j.jpba.2021.114202] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 05/24/2021] [Accepted: 06/07/2021] [Indexed: 11/19/2022]
Abstract
Oral Submucous Fibrosis (OSMF) is a type of precancerous condition of Oral cancer and considered to have the greatest malignant potential. Biopsy is an ultimate option for the conformation of the malignancy. But the invasiveness of the procedure makes it interdict. Therefore, there is an urgent need to identify effective screening and diagnostic methods which would be less invasive, rapid, more accurate and cost effective. Here, we used Attenuated Total Reflection- Fourier transform infrared spectroscopy (ATR-FTIR) with Chemometric analysis coupled with estimation of total salivary protein to discriminate OSMF and Healthy Control (HC). The present study showed the specific Infrared spectrum for OSMF patients, which was specifically differentiated from HC based on the spectral shift of proteins/amide II, carbohydrate and nucleic acid using Principal Component Analysis (PCA) and Hierarchical Clustering Analysis (HCA) with small data sets. ATR-FTIR spectroscopy of saliva coupled with total protein estimation can be used to discriminate between OSMF and HC. However, large sample size should be needed to evaluate the ATR-FTIR for consideration as a screening tool for an early diagnosis OSMF.
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Affiliation(s)
- Shayma Shaikh
- Department of Life Science, School of Sciences, Gujarat University, India
| | - Deep Kumari Yadav
- Department of Life Science, School of Sciences, Gujarat University, India
| | - Rakesh Rawal
- Department of Life Science, School of Sciences, Gujarat University, India.
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3
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El Ansari R, Alfarsi L, Craze ML, Masisi BK, Ellis IO, Rakha EA, Green AR. The solute carrier SLC7A8 is a marker of favourable prognosis in ER-positive low proliferative invasive breast cancer. Breast Cancer Res Treat 2020; 181:1-12. [PMID: 32200487 PMCID: PMC7182634 DOI: 10.1007/s10549-020-05586-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 02/29/2020] [Indexed: 12/26/2022]
Abstract
PURPOSE Breast cancer (BC) is a heterogeneous disease consisting of various subtypes, with different prognostic and therapeutic outcomes. The amino acid transporter, SLC7A8, is overexpressed in oestrogen receptor-positive BC. However, the consequence of this overexpression, in terms of disease prognosis, is still obscure. This study aimed to evaluate the biological and prognostic value of SLC7A8 in BC with emphasis on the intrinsic molecular subtypes. METHODS SLC7A8 was assessed at the genomic, using METABRIC data (n = 1980), and proteomic, using immunohistochemistry and TMA (n = 1562), levels in well-characterised primary BC cohorts. SLC7A8 expression was examined with clinicopathological parameters, molecular subtypes, and patient outcome. RESULTS SLC7A8 mRNA and SLC7A8 protein expression were strongly associated with good prognostic features, including small tumour size, low tumour grade, and good Nottingham Prognostic Index (NPI) (all P < 0.05). Expression of SLC7A8 mRNA was higher in luminal tumours compared to other subtypes (P < 0.001). High expression of SLC7A8 mRNA and SLC7A8 protein was associated with good patient outcome (P ≤ 0.001) but only in the low proliferative ER+/luminal A tumours (P = 0.01). In multivariate analysis, SLC7A8 mRNA and SLC7A8 protein were independent factors for longer breast cancer specific survival (P = 0.01 and P = 0.03), respectively. CONCLUSION SLC7A8 appears to play a role in BC and is a marker for favourable prognosis in the most predominant, ER+ low proliferative/luminal A, BC subtype. Functional assessment is necessary to reveal the specific role played by SLC7A8 in ER+ BC.
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Affiliation(s)
- Rokaya El Ansari
- Nottingham Breast Cancer Research Centre, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham Biodiscovery Institute, University Park, Nottingham, NG7 2RD, UK.,Department of Pathology, Faculty of Medicine, University of Tripoli, Tripoli, Libya
| | - Lutfi Alfarsi
- Nottingham Breast Cancer Research Centre, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham Biodiscovery Institute, University Park, Nottingham, NG7 2RD, UK
| | - Madeleine L Craze
- Nottingham Breast Cancer Research Centre, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham Biodiscovery Institute, University Park, Nottingham, NG7 2RD, UK
| | - Brendah K Masisi
- Nottingham Breast Cancer Research Centre, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham Biodiscovery Institute, University Park, Nottingham, NG7 2RD, UK
| | - Ian O Ellis
- Nottingham Breast Cancer Research Centre, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham Biodiscovery Institute, University Park, Nottingham, NG7 2RD, UK.,Histopathology, Nottingham University Hospitals NHS Trust, Hucknall Road, Nottingham, NG5 1PB, UK
| | - Emad A Rakha
- Nottingham Breast Cancer Research Centre, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham Biodiscovery Institute, University Park, Nottingham, NG7 2RD, UK.,Histopathology, Nottingham University Hospitals NHS Trust, Hucknall Road, Nottingham, NG5 1PB, UK
| | - Andrew R Green
- Nottingham Breast Cancer Research Centre, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham Biodiscovery Institute, University Park, Nottingham, NG7 2RD, UK.
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4
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Scalise M, Pochini L, Galluccio M, Console L, Indiveri C. Glutamine transporters as pharmacological targets: From function to drug design. Asian J Pharm Sci 2020; 15:207-219. [PMID: 32373200 PMCID: PMC7193454 DOI: 10.1016/j.ajps.2020.02.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 02/18/2020] [Accepted: 02/29/2020] [Indexed: 12/17/2022] Open
Abstract
Among the different targets of administered drugs, there are membrane transporters that play also a role in drug delivery and disposition. Moreover, drug-transporter interactions are responsible for off-target effects of drugs underlying their toxicity. The improvement of the drug design process is subjected to the identification of those membrane transporters mostly relevant for drug absorption, delivery and side effect production. A peculiar group of proteins with great relevance to pharmacology is constituted by the membrane transporters responsible for managing glutamine traffic in different body districts. The interest around glutamine metabolism lies in its physio-pathological role; glutamine is considered a conditionally essential amino acid because highly proliferative cells have an increased request of glutamine that cannot be satisfied only by endogenous synthesis. Then, glutamine transporters provide cells with this special nutrient. Among the glutamine transporters, SLC1A5, SLC6A14, SLC6A19, SLC7A5, SLC7A8 and some members of SLC38 family are the best characterized, so far, in both physiological and pathological conditions. Few 3D structures have been solved by CryoEM; other structural data on these transporters have been obtained by computational analysis. Interactions with drugs have been described for several transporters of this group. For some of them, the studies are at an advanced stage, for others, the studies are still in nuce and novel biochemical findings open intriguing perspectives.
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Affiliation(s)
- Mariafrancesca Scalise
- Department of DiBEST (Biologia, Ecologia e Scienze della Terra), University of Calabria, Arcavacata di Rende (CS) 87036, Italy
| | - Lorena Pochini
- Department of DiBEST (Biologia, Ecologia e Scienze della Terra), University of Calabria, Arcavacata di Rende (CS) 87036, Italy
| | - Michele Galluccio
- Department of DiBEST (Biologia, Ecologia e Scienze della Terra), University of Calabria, Arcavacata di Rende (CS) 87036, Italy
| | - Lara Console
- Department of DiBEST (Biologia, Ecologia e Scienze della Terra), University of Calabria, Arcavacata di Rende (CS) 87036, Italy
| | - Cesare Indiveri
- Department of DiBEST (Biologia, Ecologia e Scienze della Terra), University of Calabria, Arcavacata di Rende (CS) 87036, Italy
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5
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El Ansari R, Craze ML, Miligy I, Diez-Rodriguez M, Nolan CC, Ellis IO, Rakha EA, Green AR. The amino acid transporter SLC7A5 confers a poor prognosis in the highly proliferative breast cancer subtypes and is a key therapeutic target in luminal B tumours. Breast Cancer Res 2018; 20:21. [PMID: 29566741 PMCID: PMC5863851 DOI: 10.1186/s13058-018-0946-6] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Accepted: 02/26/2018] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Breast cancer (BC) is a heterogeneous disease characterised by variant biology and patient outcome. The amino acid transporter, SLC7A5, plays a role in BC although its impact on patient outcome in different BC subtypes remains to be validated. This study aimed to determine whether the clinicopathological and prognostic value of SLC7A5 is different within the molecular classes of BC. METHODS SLC7A5 was assessed at the genomic level, using Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) data (n = 1980), and proteomic level, using immunohistochemical analysis and tissue microarray (TMA) (n = 2664; 1110 training and 1554 validation sets) in well-characterised primary BC cohorts. SLC7A5 expression correlated with clinicopathological and biological parameters, molecular subtypes and patient outcome. RESULTS SLC7A5 mRNA and protein expression were strongly correlated with larger tumour size and higher grade. High expression was observed in triple negative (TN), human epidermal growth factor receptor 2 (HER2)+, and luminal B subtypes. SLC7A5 mRNA and protein expression was significantly associated with the expression of the key regulator of tumour cell metabolism, c-MYC, specifically in luminal B tumours only (p = 0.001). High expression of SLC7A5 mRNA and protein was associated with poor patient outcome (p < 0.001) but only in the highly proliferative oestrogen receptor (ER)+/ luminal B (p = 0.007) and HER2+ classes of BC (p = 0.03). In multivariate analysis, SLC7A5 protein was an independent risk factor for shorter breast-cancer-specific survival only in ER+ high-proliferation tumours (p = 0.02). CONCLUSIONS SLC7A5 appears to play a role in the aggressive highly proliferative ER+ subtype driven by MYC and could act as a potential therapeutic target. Functional assessment is necessary to reveal the specific role played by this transporter in the ER+ highly proliferative subclass and HER2+ subclass of BC.
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Affiliation(s)
- Rokaya El Ansari
- Academic Pathology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham City Hospital, Hucknall Road, Nottingham, NG5 1PB UK
| | - Madeleine L. Craze
- Academic Pathology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham City Hospital, Hucknall Road, Nottingham, NG5 1PB UK
| | - Islam Miligy
- Academic Pathology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham City Hospital, Hucknall Road, Nottingham, NG5 1PB UK
| | - Maria Diez-Rodriguez
- Academic Pathology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham City Hospital, Hucknall Road, Nottingham, NG5 1PB UK
| | - Christopher C. Nolan
- Academic Pathology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham City Hospital, Hucknall Road, Nottingham, NG5 1PB UK
| | - Ian O. Ellis
- Academic Pathology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham City Hospital, Hucknall Road, Nottingham, NG5 1PB UK
- Breast Institute, Nottingham University Hospitals NHS Trust, Hucknall Road, Nottingham, NG5 1PB UK
| | - Emad A. Rakha
- Academic Pathology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham City Hospital, Hucknall Road, Nottingham, NG5 1PB UK
- Breast Institute, Nottingham University Hospitals NHS Trust, Hucknall Road, Nottingham, NG5 1PB UK
| | - Andrew R. Green
- Academic Pathology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham City Hospital, Hucknall Road, Nottingham, NG5 1PB UK
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6
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Rai V, Mukherjee R, Routray A, Ghosh AK, Roy S, Ghosh BP, Mandal PB, Bose S, Chakraborty C. Serum-based diagnostic prediction of oral submucous fibrosis using FTIR spectrometry. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2018; 189:322-329. [PMID: 28826108 DOI: 10.1016/j.saa.2017.08.018] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 08/04/2017] [Accepted: 08/07/2017] [Indexed: 06/07/2023]
Abstract
Oral submucous fibrosis (OSF) is found to have the highest malignant potentiality among all other pre-cancerous lesions. However, its detection prior to tissue biopsy can be challenging in clinics. Moreover, biopsy examination is invasive and painful. Hence, there is an urgent need of new technology that facilitates accurate diagnostic prediction of OSF prior to biopsy. Here, we used FTIR spectroscopy coupled with chemometric techniques to distinguish the serum metabolic signatures of OSF patients (n=30) and healthy controls (n=30). Serum biochemical analyses have been performed to further support the FTIR findings. Absorbance intensities of 45 infrared wavenumbers differed significantly between OSF and normal serum FTIR spectra representing alterations in carbohydrates, proteins, lipids and nucleic acids. Nineteen prominent significant wavenumbers (P≤0.001) at 1020, 1025, 1035, 1039, 1045, 1078, 1055, 1100, 1117, 1122, 1151, 1169, 1243, 1313, 1398, 1453, 1544, 1650 and 1725cm-1 provided excellent segregation of OSF spectra from normal using multivariate statistical techniques. These findings provided essential information on the metabolic features of blood serum of OSF patients and established that FTIR spectroscopy coupled with chemometric analysis can be potentially useful in the rapid and accurate preoperative screening/diagnosis of OSF.
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Affiliation(s)
- Vertika Rai
- School of Medical Science & Technology, Indian Institute of Technology, Kharagpur, India
| | - Rashmi Mukherjee
- Advanced Technology Development Centre, Indian Institute of Technology, Kharagpur, India
| | - Aurobinda Routray
- Dept. of Electrical Engineering, Indian Institute of Technology, Kharagpur, India
| | - Ananta Kumar Ghosh
- Dept. of Biotechnology, Indian Institute of Technology, Kharagpur, India
| | - Seema Roy
- B C Roy Technology Hospital, Indian Institute of Technology, Kharagpur, India
| | - Barnali Paul Ghosh
- B C Roy Technology Hospital, Indian Institute of Technology, Kharagpur, India
| | | | - Surajit Bose
- Awadh Dental College and Hospital, Tata Jamshedpur, India
| | - Chandan Chakraborty
- School of Medical Science & Technology, Indian Institute of Technology, Kharagpur, India.
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7
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Khosravian P, Shafiee Ardestani M, Khoobi M, Ostad SN, Dorkoosh FA, Akbari Javar H, Amanlou M. Mesoporous silica nanoparticles functionalized with folic acid/methionine for active targeted delivery of docetaxel. Onco Targets Ther 2016; 9:7315-7330. [PMID: 27980423 PMCID: PMC5144897 DOI: 10.2147/ott.s113815] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Mesoporous silica nanoparticles (MSNs) are known as carriers with high loading capacity and large functionalizable surface area for target-directed delivery. In this study, a series of docetaxel-loaded folic acid- or methionine-functionalized mesoporous silica nanoparticles (DTX/MSN-FA or DTX/MSN-Met) with large pores and amine groups at inner pore surface properties were prepared. The results showed that the MSNs were successfully synthesized, having good pay load and pH-sensitive drug release kinetics. The cellular investigation on MCF-7 cells showed better performance of cytotoxicity and cell apoptosis and an increase in cellular uptake of targeted nanoparticles. In vivo fluorescent imaging on healthy BALB/c mice proved that bare MSN-NH2 are mostly accumulated in the liver but MSN-FA or MSN-Met are more concentrated in the kidney. Importantly, ex vivo fluorescent images of tumor-induced BALB/c mice organs revealed the ability of MSN-FA to reach the tumor tissues. In conclusion, DTX/MSNs exhibited a good anticancer activity and enhanced the possibility of targeted drug delivery for breast cancer.
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Affiliation(s)
| | | | | | | | | | | | - Massoud Amanlou
- Department of Medicinal Chemistry, Faculty of Pharmacy and Pharmaceutical Sciences Research Center
- Drug Design and Development Research Center, Tehran University of Medical Sciences, Tehran, Iran
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8
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Weber J, Haberkorn U, Mier W. Cancer stratification by molecular imaging. Int J Mol Sci 2015; 16:4918-46. [PMID: 25749472 PMCID: PMC4394457 DOI: 10.3390/ijms16034918] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Revised: 02/13/2015] [Accepted: 02/17/2015] [Indexed: 12/29/2022] Open
Abstract
The lack of specificity of traditional cytotoxic drugs has triggered the development of anticancer agents that selectively address specific molecular targets. An intrinsic property of these specialized drugs is their limited applicability for specific patient subgroups. Consequently, the generation of information about tumor characteristics is the key to exploit the potential of these drugs. Currently, cancer stratification relies on three approaches: Gene expression analysis and cancer proteomics, immunohistochemistry and molecular imaging. In order to enable the precise localization of functionally expressed targets, molecular imaging combines highly selective biomarkers and intense signal sources. Thus, cancer stratification and localization are performed simultaneously. Many cancer types are characterized by altered receptor expression, such as somatostatin receptors, folate receptors or Her2 (human epidermal growth factor receptor 2). Similar correlations are also known for a multitude of transporters, such as glucose transporters, amino acid transporters or hNIS (human sodium iodide symporter), as well as cell specific proteins, such as the prostate specific membrane antigen, integrins, and CD20. This review provides a comprehensive description of the methods, targets and agents used in molecular imaging, to outline their application for cancer stratification. Emphasis is placed on radiotracers which are used to identify altered expression patterns of cancer associated markers.
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Affiliation(s)
- Justus Weber
- Heidelberg University Hospital, Department of Nuclear Medicine, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany.
| | - Uwe Haberkorn
- Heidelberg University Hospital, Department of Nuclear Medicine, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany.
| | - Walter Mier
- Heidelberg University Hospital, Department of Nuclear Medicine, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany.
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Kadiyala KG, Datta A, Tanwar J, Adhikari A, Kumar BSH, Chuttani K, Thirumal M, Mishra AK. Metal Based Imaging Probes of DO3A-Act-Met for LAT1 Mediated Methionine Specific Tumors : Synthesis and Preclinical Evaluation. Pharm Res 2014; 32:955-67. [DOI: 10.1007/s11095-014-1509-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Accepted: 08/29/2014] [Indexed: 11/30/2022]
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10
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Pochini L, Scalise M, Galluccio M, Indiveri C. Membrane transporters for the special amino acid glutamine: structure/function relationships and relevance to human health. Front Chem 2014; 2:61. [PMID: 25157349 PMCID: PMC4127817 DOI: 10.3389/fchem.2014.00061] [Citation(s) in RCA: 172] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 07/16/2014] [Indexed: 12/26/2022] Open
Abstract
Glutamine together with glucose is essential for body's homeostasis. It is the most abundant amino acid and is involved in many biosynthetic, regulatory and energy production processes. Several membrane transporters which differ in transport modes, ensure glutamine homeostasis by coordinating its absorption, reabsorption and delivery to tissues. These transporters belong to different protein families, are redundant and ubiquitous. Their classification, originally based on functional properties, has recently been associated with the SLC nomenclature. Function of glutamine transporters is studied in cells over-expressing the transporters or, more recently in proteoliposomes harboring the proteins extracted from animal tissues or over-expressed in microorganisms. The role of the glutamine transporters is linked to their transport modes and coupling with Na+ and H+. Most transporters share specificity for other neutral or cationic amino acids. Na+-dependent co-transporters efficiently accumulate glutamine while antiporters regulate the pools of glutamine and other amino acids. The most acknowledged glutamine transporters belong to the SLC1, 6, 7, and 38 families. The members involved in the homeostasis are the co-transporters B0AT1 and the SNAT members 1, 2, 3, 5, and 7; the antiporters ASCT2, LAT1 and 2. The last two are associated to the ancillary CD98 protein. Some information on regulation of the glutamine transporters exist, which, however, need to be deepened. No information at all is available on structures, besides some homology models obtained using similar bacterial transporters as templates. Some models of rat and human glutamine transporters highlight very similar structures between the orthologs. Moreover the presence of glycosylation and/or phosphorylation sites located at the extracellular or intracellular faces has been predicted. ASCT2 and LAT1 are over-expressed in several cancers, thus representing potential targets for pharmacological intervention.
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Affiliation(s)
- Lorena Pochini
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria Arcavacata di Rende, Italy
| | - Mariafrancesca Scalise
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria Arcavacata di Rende, Italy
| | - Michele Galluccio
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria Arcavacata di Rende, Italy
| | - Cesare Indiveri
- Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria Arcavacata di Rende, Italy
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Yun DW, Lee SA, Park MG, Kim JS, Yu SK, Park MR, Kim SG, Oh JS, Kim CS, Kim HJ, Kim JS, Chun HS, Kanai Y, Endou H, Wempe MF, Kim DK. JPH203, an L-type amino acid transporter 1-selective compound, induces apoptosis of YD-38 human oral cancer cells. J Pharmacol Sci 2014; 124:208-17. [PMID: 24492461 DOI: 10.1254/jphs.13154fp] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Compared to most normal cells that express L-type amino acid transporter 2, L-type amino acid transporter 1 is highly expressed in cancer cells and presumed to support their elevated growth and proliferation. This study examined JPH203, a potent and selective L-type amino acid transporter 1 inhibitor, and its ability to suppress YD-38 human oral cancer cell growth. The YD-38 cells express L-type amino acid transporter 1 with its associating protein 4F2 heavy chain, but not L-type amino acid transporter 2. JPH203 and BCH, a non-selective L-type amino acid transporter inhibitor, completely inhibited l-leucine uptake in YD-38 cells. As expected, the intrinsic affinity of JPH203 to inhibit l-leucine uptake was far more efficient than BCH. Likewise, JPH203 and BCH inhibited YD-38 cell growth, with JPH203 being superior to BCH. JPH203 up-regulated the population of apoptotic YD-38 cells through the activation of apoptotic factors, including caspases and PARP. These results suggest that the inhibition of L-type amino acid transporter 1 activity via JPH203, which may act as a potential novel anti-oral-cancer agent, leads to apoptosis by inducing the intracellular depletion of the neutral amino acids essential for cancer cell growth in YD-38 human oral cancer cells.
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Affiliation(s)
- Dae-Woong Yun
- Oral Biology Research Institute, Chosun University School of Dentistry, Korea
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12
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The SLC3 and SLC7 families of amino acid transporters. Mol Aspects Med 2013; 34:139-58. [PMID: 23506863 DOI: 10.1016/j.mam.2012.10.007] [Citation(s) in RCA: 454] [Impact Index Per Article: 41.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Accepted: 08/15/2012] [Indexed: 01/18/2023]
Abstract
Amino acids are necessary for all living cells and organisms. Specialized transporters mediate the transfer of amino acids across plasma membranes. Malfunction of these proteins can affect whole-body homoeostasis giving raise to diverse human diseases. Here, we review the main features of the SLC3 and SLC7 families of amino acid transporters. The SLC7 family is divided into two subfamilies, the cationic amino acid transporters (CATs), and the L-type amino acid transporters (LATs). The latter are the light or catalytic subunits of the heteromeric amino acid transporters (HATs), which are associated by a disulfide bridge with the heavy subunits 4F2hc or rBAT. These two subunits are glycoproteins and form the SLC3 family. Most CAT subfamily members were functionally characterized and shown to function as facilitated diffusers mediating the entry and efflux of cationic amino acids. In certain cells, CATs play an important role in the delivery of L-arginine for the synthesis of nitric oxide. HATs are mostly exchangers with a broad spectrum of substrates and are crucial in renal and intestinal re-absorption and cell redox balance. Furthermore, the role of the HAT 4F2hc/LAT1 in tumor growth and the application of LAT1 inhibitors and PET tracers for reduction of tumor progression and imaging of tumors are discussed. Finally, we describe the link between specific mutations in HATs and the primary inherited aminoacidurias, cystinuria and lysinuric protein intolerance.
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Haining Z, Kawai N, Miyake K, Okada M, Okubo S, Zhang X, Fei Z, Tamiya T. Relation of LAT1/4F2hc expression with pathological grade, proliferation and angiogenesis in human gliomas. BMC Clin Pathol 2012; 12:4. [PMID: 22373026 PMCID: PMC3305678 DOI: 10.1186/1472-6890-12-4] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2011] [Accepted: 02/28/2012] [Indexed: 11/26/2022] Open
Abstract
Background LAT1/4F2hc heterodimeric complex is a major route for the transport of large neutral essential amino acids through the plasma membrane. Although it has been shown that LAT1/4F2hc is highly expressed in a variety of human tumors including gliomas, and LAT1 over-expression is associated with glioma grade and poor prognosis of glioma patients, the precise tissue location of LAT1/4F2hc in gliomas and the precise role of LAT1/4F2hc in glioma biological features remain unclear. Methods In the current study, the expressions of LAT1, 4F2hc, CD34 and Ki-67 were investigated by immunohistochemistry in 62 cases of human brain glioma; LAT1/4F2hc expression level, Ki-67 labeling index (Ki-67 LI) and microvessel density (MVD) were measured semi-quantitatively; and the correlation of LAT1/4F2hc expression with histopathological features, Ki-67 LI and MVD in gliomas was further analyzed. Results The results showed that both LAT1 and 4F2hc were expressed in all examined specimens. LAT1 but 4F2hc expression levels significantly correlated with the pathological grade and both expression levels significantly correlated with Ki-67 LI of gliomas. We also demonstrated that both LAT1 and 4F2hc immunoreactivity were observed in tumor cells as well as vascular endothelia; furthermore, the LAT1 expression level was markedly associated with glioma MVD as well. Conclusion LAT1/4F2hc over-expression is closely correlates with the malignant phenotype and proliferation of gliomas, and LAT1 was associates with glioma angiogenesis. LAT1/4F2hc, especially LAT1, may become a novel potential molecular target for glioma biological therapy.
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Affiliation(s)
- Zhen Haining
- Department of Neurological Surgery, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa, 761-0793, Japan.
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Preclinical characterization of 18F-D-FPHCys, a new amino acid-based PET tracer. Eur J Nucl Med Mol Imaging 2011; 39:703-12. [DOI: 10.1007/s00259-011-2017-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2011] [Accepted: 11/22/2011] [Indexed: 12/13/2022]
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Uno K, Kuwabara H, Terado Y, Kojima K, Kawakami T, Kamma H, Sakurai H, Sakamoto A, Kurata A. Divergent expression of L-type amino acid transporter 1 during uterine cervical carcinogenesis. Hum Pathol 2011; 42:1660-6. [DOI: 10.1016/j.humpath.2011.01.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2010] [Revised: 12/27/2010] [Accepted: 01/04/2011] [Indexed: 10/18/2022]
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Tumor suppressor gene adenomatous polyposis coli downregulates intestinal transport. Pflugers Arch 2011; 461:527-36. [DOI: 10.1007/s00424-011-0945-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Revised: 02/15/2011] [Accepted: 02/16/2011] [Indexed: 12/21/2022]
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Liang Z, Cho HT, Williams L, Zhu A, Liang K, Huang K, Wu H, Jiang C, Hong S, Crowe R, Goodman MM, Shim H. Potential Biomarker of L-type Amino Acid Transporter 1 in Breast Cancer Progression. Nucl Med Mol Imaging 2010; 45:93-102. [PMID: 24899987 DOI: 10.1007/s13139-010-0068-2] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Accepted: 11/04/2010] [Indexed: 12/16/2022] Open
Abstract
PURPOSE L-type amino acid transporter 1 (LAT1) is essential for the transport of large neutral amino acids. However, its role in breast cancer growth remains largely unknown. The purpose of the study is to investigate whether LAT1 is a potential biomarker for the diagnosis and treatment of breast cancer. METHODS LAT1 mRNA and protein levels in breast cancer cell lines and tissues were analyzed. In addition, the effects of targeting LAT1 for the inhibition of breast cancer cell tumorigenesis were assessed with soft agar assay. The imaging of xenograft with anti-1-amino-3-[(18)F]fluorocyclobutane-1-carboxylic acid (anti-[(18)F]FACBC) PET was assessed for its diagnostic biomarker potential. RESULTS Normal breast tissue or low malignant cell lines expressed low levels of LAT1 mRNA and protein, while highly malignant cancer cell lines and high-grade breast cancer tissue expressed high levels of LAT1. In addition, higher expression levels of LAT1 in breast cancer tissues were consistent with advanced-stage breast cancer. Furthermore, the blockade of LAT1 with its inhibitor, 2-amino-bicyclo[2.2.1]heptane-2-carboxylic acid (BCH), or the knockdown of LAT1 with siRNA, inhibited proliferation and tumorigenesis of breast cancer cells. A leucine analog, anti-[(18)F]FACBC, has been demonstrated to be an excellent PET tracer for the non-invasive imaging of malignant breast cancer using an orthotopic animal model. CONCLUSIONS The overexpression of LAT1 is required for the progression of breast cancer. LAT1 represents a potential biomarker for therapy and diagnosis of breast cancer. Anti-[(18)F]FACBC that correlates with LAT1 function is a potential PET tracer for malignant breast tumor imaging.
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Affiliation(s)
- Zhongxing Liang
- Department of Radiology, Emory University School of Medicine, 1365C Clifton Road NE, Atlanta, GA 30322 USA ; Winship Cancer Institute, Emory University School of Medicine, Atlanta, USA
| | - Heidi T Cho
- Department of Radiology, Emory University School of Medicine, 1365C Clifton Road NE, Atlanta, GA 30322 USA
| | - Larry Williams
- Department of Radiology, Emory University School of Medicine, 1365C Clifton Road NE, Atlanta, GA 30322 USA
| | - Aizhi Zhu
- Department of Radiology, Emory University School of Medicine, 1365C Clifton Road NE, Atlanta, GA 30322 USA
| | - Ke Liang
- Department of Radiology, Emory University School of Medicine, 1365C Clifton Road NE, Atlanta, GA 30322 USA
| | - Ke Huang
- Department of Radiology, Emory University School of Medicine, 1365C Clifton Road NE, Atlanta, GA 30322 USA
| | - Hui Wu
- Department of Radiology, Emory University School of Medicine, 1365C Clifton Road NE, Atlanta, GA 30322 USA
| | - Chunsu Jiang
- Department of Radiology, Emory University School of Medicine, 1365C Clifton Road NE, Atlanta, GA 30322 USA
| | - Samuel Hong
- Department of Radiology, Emory University School of Medicine, 1365C Clifton Road NE, Atlanta, GA 30322 USA
| | - Ronald Crowe
- Department of Radiology, Emory University School of Medicine, 1365C Clifton Road NE, Atlanta, GA 30322 USA
| | - Mark M Goodman
- Department of Radiology, Emory University School of Medicine, 1365C Clifton Road NE, Atlanta, GA 30322 USA ; Winship Cancer Institute, Emory University School of Medicine, Atlanta, USA
| | - Hyunsuk Shim
- Department of Radiology, Emory University School of Medicine, 1365C Clifton Road NE, Atlanta, GA 30322 USA ; Winship Cancer Institute, Emory University School of Medicine, Atlanta, USA
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Xia Luo, Coon JS, Su E, Kerry Pearson E, Ping Yin, Ishikawa H, Bulun SE. LAT1 Regulates Growth of Uterine Leiomyoma Smooth Muscle Cells. Reprod Sci 2010; 17:791-7. [DOI: 10.1177/1933719110372419] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Xia Luo
- Division of Reproductive Biology Research, Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA, Department of Obstetrics and Gynecology, Qilu Hospital, Shandong University, Jinan, Shandong, People's Republic of China
| | - John S. Coon
- Division of Reproductive Biology Research, Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Emily Su
- Division of Reproductive Biology Research, Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Elizabeth Kerry Pearson
- Division of Reproductive Biology Research, Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Ping Yin
- Division of Reproductive Biology Research, Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Hiroshi Ishikawa
- Division of Reproductive Biology Research, Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Serdar E. Bulun
- Division of Reproductive Biology Research, Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA,
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Kim CS, Moon IS, Park JH, Shin WC, Chun HS, Lee SY, Kook JK, Kim HJ, Park JC, Endou H, Kanai Y, Lee BK, Kim DK. Inhibition of L-Type Amino Acid Transporter Modulates the Expression of Cell Cycle Regulatory Factors in KB Oral Cancer Cells. Biol Pharm Bull 2010; 33:1117-21. [DOI: 10.1248/bpb.33.1117] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Chun Sung Kim
- Department of Oralbiochemistry, Chosun University School of Dentistry
| | - In-Sung Moon
- Oral Biology Research Institute, Chosun University School of Dentistry
| | - Ju-Hyun Park
- Oral Biology Research Institute, Chosun University School of Dentistry
| | - Woo-Cheol Shin
- Oral Biology Research Institute, Chosun University School of Dentistry
| | - Hong Sung Chun
- Department of Biotechnology (BK21 Program), Chosun University
| | - Sook-Young Lee
- Research Center for Oral Disease Regulation of the Aged, Chosun University School of Dentistry
| | - Joong-Ki Kook
- Department of Oralbiochemistry, Chosun University School of Dentistry
| | - Heung-Joong Kim
- Oral Biology Research Institute, Chosun University School of Dentistry
| | - Joo-Cheol Park
- Department of Oral Histology and Developmental Biology, Seoul National University School of Dentistry
| | - Hitoshi Endou
- Department of Pharmacology and Toxicology, Kyorin University School of Medicine
| | - Yoshikatsu Kanai
- Department of Pharmacology, Osaka University Graduate School of Medicine
| | | | - Do Kyung Kim
- Oral Biology Research Institute, Chosun University School of Dentistry
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Ohno Y, Suda K, Masuko K, Yagi H, Hashimoto Y, Masuko T. Production and characterization of highly tumor-specific rat monoclonal antibodies recognizing the extracellular domain of human L-type amino-acid transporter 1. Cancer Sci 2008; 99:1000-7. [PMID: 18294274 PMCID: PMC11160021 DOI: 10.1111/j.1349-7006.2008.00770.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2007] [Revised: 01/07/2008] [Accepted: 01/10/2008] [Indexed: 11/30/2022] Open
Abstract
L-type large amino acid transporter (LAT) 1, the first light chain (lc) of cluster of differentiation 98 (CD98) to be identified, is associated with the heavy chain (hc) of CD98 and expressed on the surface of various tumor cells irrespective of their origin. Because LAT1 is a 12-pass membrane protein and its possible immunogenic extracellular region is very small, specific monoclonal antibodies (mAb) had not been developed. We report the successful preparation and characterization of mAb recognizing the extracellular domain of human LAT1 protein. Two mAb were selected from hybridoma clones established by fusing mouse myeloma cells and spleen cells from rats immunized against RH7777 rat hepatoma cells expressing recombinant green fluorescent protein fused to human LAT1 protein. Designated SOL22 and SOL69, these mAb specifically reacted with the extracellular domain of LAT1 on cells transfected with cDNA of LAT1, but not with cells transfected with cDNA of other CD98 lc, namely, LAT2, y(+)LAT1, y(+)LAT2, and xCT amino acid transporters. These mAb immunoprecipitated 35- and 90-kDa proteins under reducing conditions in extracts prepared from human HeLa tumor cells, indicating the existence of intermolecular disulfide bonds between cysteine residues in the 90-kDa hc and 35-kDa lc (LAT1). SOL22 and SOL69 mAb reacted with a wide variety of living unfixed human tumor cell lines, but were only weakly reactive with HEK293F human embryonic kidney cells and human peripheral blood cells. Comparative immunohistochemical analyses of normal human tissues with anti-CD98 hc and anti-LAT1 revealed LAT1 to be an excellent molecular target for antibody therapy, possibly even superior to CD98 hc.
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Affiliation(s)
- Yoshiya Ohno
- Cell Biology Laboratory, Department of Pharmaceutical Sciences, School of Pharmacy, Kinki University, 4-1 Kowakae 3-chome, Higashiosaka-shi, Osaka 577-8502, Japan
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Kaper T, Looger LL, Takanaga H, Platten M, Steinman L, Frommer WB. Nanosensor detection of an immunoregulatory tryptophan influx/kynurenine efflux cycle. PLoS Biol 2007; 5:e257. [PMID: 17896864 PMCID: PMC1988858 DOI: 10.1371/journal.pbio.0050257] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2007] [Accepted: 07/30/2007] [Indexed: 12/20/2022] Open
Abstract
Mammalian cells rely on cellular uptake of the essential amino acid tryptophan. Tryptophan sequestration by up-regulation of the key enzyme for tryptophan degradation, indoleamine 2,3-dioxygenase (IDO), e.g., in cancer and inflammation, is thought to suppress the immune response via T cell starvation. Additionally, the excreted tryptophan catabolites (kynurenines) induce apoptosis of lymphocytes. Whereas tryptophan transport systems have been identified, the molecular nature of kynurenine export remains unknown. To measure cytosolic tryptophan steady-state levels and flux in real time, we developed genetically encoded fluorescence resonance energy transfer nanosensors (FLIPW). The transport properties detected by FLIPW in KB cells, a human oral cancer cell line, and COS-7 cells implicate LAT1, a transporter that is present in proliferative tissues like cancer, in tryptophan uptake. Importantly, we found that this transport system mediates tryptophan/kynurenine exchange. The tryptophan influx/kynurenine efflux cycle couples tryptophan starvation to elevation of kynurenine serum levels, providing a two-pronged induction of apoptosis in neighboring cells. The strict coupling protects cells that overproduce IDO from kynurenine accumulation. Consequently, this mechanism may contribute to immunosuppression involved in autoimmunity and tumor immune escape.
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Affiliation(s)
- Thijs Kaper
- Department of Plant Biology, Carnegie Institution, Stanford, California, United States of America
| | - Loren L Looger
- Department of Plant Biology, Carnegie Institution, Stanford, California, United States of America
| | - Hitomi Takanaga
- Department of Plant Biology, Carnegie Institution, Stanford, California, United States of America
| | - Michael Platten
- Department of Neuro-oncology, University Hospital of Heidelberg, INF 400, Heidelberg, Germany
- German Cancer Research Center, INF 280, Heidelberg, Germany
| | - Lawrence Steinman
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, California, United States of America
| | - Wolf B Frommer
- Department of Plant Biology, Carnegie Institution, Stanford, California, United States of America
- * To whom correspondence should be addressed. E-mail:
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