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Busà R, Bulati M, Badami E, Zito G, Maresca DC, Conaldi PG, Ercolano G, Ianaro A. Tissue-Resident Innate Immune Cell-Based Therapy: A Cornerstone of Immunotherapy Strategies for Cancer Treatment. Front Cell Dev Biol 2022; 10:907572. [PMID: 35757002 PMCID: PMC9221069 DOI: 10.3389/fcell.2022.907572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 05/03/2022] [Indexed: 11/18/2022] Open
Abstract
Cancer immunotherapy has led to impressive advances in cancer treatment. Unfortunately, in a high percentage of patients is difficult to consistently restore immune responses to eradicate established tumors. It is well accepted that adaptive immune cells, such as B lymphocytes, CD4+ helper T lymphocytes, and CD8+ cytotoxic T-lymphocytes (CTLs), are the most effective cells able to eliminate tumors. However, it has been recently reported that innate immune cells, including natural killer cells (NK), dendritic cells (DC), macrophages, myeloid-derived suppressor cells (MDSCs), and innate lymphoid cells (ILCs), represent important contributors to modulating the tumor microenvironment and shaping the adaptive tumor response. In fact, their role as a bridge to adaptive immunity, make them an attractive therapeutic target for cancer treatment. Here, we provide a comprehensive overview of the pleiotropic role of tissue-resident innate immune cells in different tumor contexts. In addition, we discuss how current and future therapeutic approaches targeting innate immune cells sustain the adaptive immune system in order to improve the efficacy of current tumor immunotherapies.
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Affiliation(s)
- Rosalia Busà
- Research Department, Mediterranean Institute for Transplantation and Advanced Specialized Therapies (IRCCS ISMETT), Palermo, Italy
| | - Matteo Bulati
- Research Department, Mediterranean Institute for Transplantation and Advanced Specialized Therapies (IRCCS ISMETT), Palermo, Italy
| | - Ester Badami
- Research Department, Mediterranean Institute for Transplantation and Advanced Specialized Therapies (IRCCS ISMETT), Palermo, Italy
- Ri.MED Foundation, Palermo, Italy
| | - Giovanni Zito
- Research Department, Mediterranean Institute for Transplantation and Advanced Specialized Therapies (IRCCS ISMETT), Palermo, Italy
| | | | - Pier Giulio Conaldi
- Research Department, Mediterranean Institute for Transplantation and Advanced Specialized Therapies (IRCCS ISMETT), Palermo, Italy
| | - Giuseppe Ercolano
- Department of Pharmacy, School of Medicine, University of Naples Federico II, Naples, Italy
- *Correspondence: Giuseppe Ercolano,
| | - Angela Ianaro
- Department of Pharmacy, School of Medicine, University of Naples Federico II, Naples, Italy
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Subtil B, Cambi A, Tauriello DVF, de Vries IJM. The Therapeutic Potential of Tackling Tumor-Induced Dendritic Cell Dysfunction in Colorectal Cancer. Front Immunol 2021; 12:724883. [PMID: 34691029 PMCID: PMC8527179 DOI: 10.3389/fimmu.2021.724883] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 09/14/2021] [Indexed: 12/12/2022] Open
Abstract
Colorectal cancer (CRC) is the third most diagnosed malignancy and the second leading cause of cancer-related deaths worldwide. Locally advanced and metastatic disease exhibit resistance to therapy and are prone to recurrence. Despite significant advances in standard of care and targeted (immuno)therapies, the treatment effects in metastatic CRC patients have been modest. Untreatable cancer metastasis accounts for poor prognosis and most CRC deaths. The generation of a strong immunosuppressive tumor microenvironment (TME) by CRC constitutes a major hurdle for tumor clearance by the immune system. Dendritic cells (DCs), often impaired in the TME, play a critical role in the initiation and amplification of anti-tumor immune responses. Evidence suggests that tumor-mediated DC dysfunction is decisive for tumor growth and metastasis initiation, as well as for the success of immunotherapies. Unravelling and understanding the complex crosstalk between CRC and DCs holds promise for identifying key mechanisms involved in tumor progression and spread that can be exploited for therapy. The main goal of this review is to provide an overview of the current knowledge on the impact of CRC-driven immunosuppression on DCs phenotype and functionality, and its significance for disease progression, patient prognosis, and treatment response. Moreover, present knowledge gaps will be highlighted as promising opportunities to further understand and therapeutically target DC dysfunction in CRC. Given the complexity and heterogeneity of CRC, future research will benefit from the use of patient-derived material and the development of in vitro organoid-based co-culture systems to model and study DCs within the CRC TME.
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Affiliation(s)
- Beatriz Subtil
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands
| | - Alessandra Cambi
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands
| | - Daniele V. F. Tauriello
- Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands
| | - I. Jolanda M. de Vries
- Department of Tumor Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, Netherlands
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Del Prete A, Sozio F, Barbazza I, Salvi V, Tiberio L, Laffranchi M, Gismondi A, Bosisio D, Schioppa T, Sozzani S. Functional Role of Dendritic Cell Subsets in Cancer Progression and Clinical Implications. Int J Mol Sci 2020; 21:ijms21113930. [PMID: 32486257 PMCID: PMC7312661 DOI: 10.3390/ijms21113930] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Revised: 05/28/2020] [Accepted: 05/29/2020] [Indexed: 12/11/2022] Open
Abstract
Dendritic cells (DCs) constitute a complex network of cell subsets with common functions but also with many divergent aspects. All dendritic cell subsets share the ability to prime T cell response and to undergo a complex trafficking program related to their stage of maturation and function. For these reasons, dendritic cells are implicated in a large variety of both protective and detrimental immune responses, including a crucial role in promoting anti-tumor responses. Although cDC1s are the most potent subset in tumor antigen cross-presentation, they are not sufficient to induce full-strength anti-tumor cytotoxic T cell response and need close interaction and cooperativity with the other dendritic cell subsets, namely cDC2s and pDCs. This review will take into consideration different aspects of DC biology, including the functional role of dendritic cell subsets in both fostering and suppressing tumor growth, the mechanisms underlying their recruitment into the tumor microenvironment, as well as the prognostic value and the potentiality of dendritic cell therapeutic targeting. Understanding the specificity of dendritic cell subsets will allow to gain insights on role of these cells in pathological conditions and to design new selective promising therapeutic approaches.
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Affiliation(s)
- Annalisa Del Prete
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy; (A.D.P.); (F.S.); (I.B.); (V.S.); (L.T.); (M.L.); (D.B.); (T.S.)
- Humanitas Clinical and Research Center—IRCCS, Via Manzoni 56, 20089 Rozzano (MI), Italy
| | - Francesca Sozio
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy; (A.D.P.); (F.S.); (I.B.); (V.S.); (L.T.); (M.L.); (D.B.); (T.S.)
- Humanitas Clinical and Research Center—IRCCS, Via Manzoni 56, 20089 Rozzano (MI), Italy
| | - Ilaria Barbazza
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy; (A.D.P.); (F.S.); (I.B.); (V.S.); (L.T.); (M.L.); (D.B.); (T.S.)
| | - Valentina Salvi
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy; (A.D.P.); (F.S.); (I.B.); (V.S.); (L.T.); (M.L.); (D.B.); (T.S.)
| | - Laura Tiberio
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy; (A.D.P.); (F.S.); (I.B.); (V.S.); (L.T.); (M.L.); (D.B.); (T.S.)
| | - Mattia Laffranchi
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy; (A.D.P.); (F.S.); (I.B.); (V.S.); (L.T.); (M.L.); (D.B.); (T.S.)
| | - Angela Gismondi
- Laboratory Affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Department of Molecular Medicine, Sapienza University of Rome, Viale Regina Elena 291, 00161 Rome, Italy;
| | - Daniela Bosisio
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy; (A.D.P.); (F.S.); (I.B.); (V.S.); (L.T.); (M.L.); (D.B.); (T.S.)
| | - Tiziana Schioppa
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy; (A.D.P.); (F.S.); (I.B.); (V.S.); (L.T.); (M.L.); (D.B.); (T.S.)
- Humanitas Clinical and Research Center—IRCCS, Via Manzoni 56, 20089 Rozzano (MI), Italy
| | - Silvano Sozzani
- Laboratory Affiliated to Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Department of Molecular Medicine, Sapienza University of Rome, Viale Regina Elena 291, 00161 Rome, Italy;
- Correspondence: ; Tel.: +39-06-4434-0632
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Patente TA, Pinho MP, Oliveira AA, Evangelista GCM, Bergami-Santos PC, Barbuto JAM. Human Dendritic Cells: Their Heterogeneity and Clinical Application Potential in Cancer Immunotherapy. Front Immunol 2019; 9:3176. [PMID: 30719026 PMCID: PMC6348254 DOI: 10.3389/fimmu.2018.03176] [Citation(s) in RCA: 226] [Impact Index Per Article: 45.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 12/24/2018] [Indexed: 12/13/2022] Open
Abstract
Dendritic cells (DC) are professional antigen presenting cells, uniquely able to induce naïve T cell activation and effector differentiation. They are, likewise, involved in the induction and maintenance of immune tolerance in homeostatic conditions. Their phenotypic and functional heterogeneity points to their great plasticity and ability to modulate, according to their microenvironment, the acquired immune response and, at the same time, makes their precise classification complex and frequently subject to reviews and improvement. This review will present general aspects of the DC physiology and classification and will address their potential and actual uses in the management of human disease, more specifically cancer, as therapeutic and monitoring tools. New combination treatments with the participation of DC will be also discussed.
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Affiliation(s)
- Thiago A Patente
- Laboratory of Tumor Immunology, Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Mariana P Pinho
- Laboratory of Tumor Immunology, Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Aline A Oliveira
- Laboratory of Tumor Immunology, Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Gabriela C M Evangelista
- Laboratory of Tumor Immunology, Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Patrícia C Bergami-Santos
- Laboratory of Tumor Immunology, Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - José A M Barbuto
- Laboratory of Tumor Immunology, Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.,Discipline of Molecular Medicine, Department of Medicine, Faculty of Medicine, University of São Paulo, São Paulo, Brazil
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Zhao YH, Zhang XF, Zhao YQ, Bai F, Qin F, Sun J, Dong Y. Time-series analysis in imatinib-resistant chronic myeloid leukemia K562-cells under different drug treatments. ACTA ACUST UNITED AC 2017; 37:621-627. [PMID: 28786057 PMCID: PMC7088819 DOI: 10.1007/s11596-017-1781-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 05/11/2017] [Indexed: 12/15/2022]
Abstract
Chronic myeloid leukemia (CML) is characterized by the accumulation of active BCR-ABL protein. Imatinib is the first-line treatment of CML; however, many patients are resistant to this drug. In this study, we aimed to compare the differences in expression patterns and functions of time-series genes in imatinib-resistant CML cells under different drug treatments. GSE24946 was downloaded from the GEO database, which included 17 samples of K562-r cells with (n=12) or without drug administration (n=5). Three drug treatment groups were considered for this study: arsenic trioxide (ATO), AMN107, and ATO+AMN107. Each group had one sample at each time point (3, 12, 24, and 48 h). Time-series genes with a ratio of standard deviation/average (coefficient of variation) >0.15 were screened, and their expression patterns were revealed based on Short Time-series Expression Miner (STEM). Then, the functional enrichment analysis of time-series genes in each group was performed using DAVID, and the genes enriched in the top ten functional categories were extracted to detect their expression patterns. Different time-series genes were identified in the three groups, and most of them were enriched in the ribosome and oxidative phosphorylation pathways. Time-series genes in the three treatment groups had different expression patterns and functions. Time-series genes in the ATO group (e.g. CCNA2 and DAB2) were significantly associated with cell adhesion, those in the AMN107 group were related to cellular carbohydrate metabolic process, while those in the ATO+AMN107 group (e.g. AP2M1) were significantly related to cell proliferation and antigen processing. In imatinib-resistant CML cells, ATO could influence genes related to cell adhesion, AMN107 might affect genes involved in cellular carbohydrate metabolism, and the combination therapy might regulate genes involved in cell proliferation.
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Affiliation(s)
- Yan-Hong Zhao
- Department of Hematology, the First Affiliated Hospital, Harbin Medical University, Harbin, 150001, China.
| | - Xue-Fang Zhang
- Department of Hematology, the Second Affiliated Hospital, Qiqihaer Medical College, Qiqihaer, 161006, China
| | - Yan-Qiu Zhao
- Department of Hematology, the First Affiliated Hospital, Harbin Medical University, Harbin, 150001, China
| | - Fan Bai
- Department of Hematology, the First Affiliated Hospital, Harbin Medical University, Harbin, 150001, China
| | - Fan Qin
- Department of Hematology, the First Affiliated Hospital, Harbin Medical University, Harbin, 150001, China
| | - Jing Sun
- Department of Hematology, the First Affiliated Hospital, Harbin Medical University, Harbin, 150001, China
| | - Ying Dong
- Department of Hematology, the First Affiliated Hospital, Harbin Medical University, Harbin, 150001, China
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Kundra A, Wang JC. Interferon induced thrombotic microangiopathy (TMA): Analysis and concise review. Crit Rev Oncol Hematol 2017; 112:103-112. [PMID: 28325251 DOI: 10.1016/j.critrevonc.2017.02.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 12/31/2016] [Accepted: 02/14/2017] [Indexed: 12/17/2022] Open
Abstract
Interferon (IFN) has been associated with development of thrombotic microangiopathy including thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome (HUS). We reviewed literature from the earliest reported association in 1993, to July 2016 and found 68 cases. Analysis of this data shows: (1) Mean age at diagnosis was 47 years (95% CI, 44-50). (2) Majority of cases were seen where IFN was used for the treatment of chronic myelogenous leukemia (CML), multiple sclerosis (MS), chronic hepatitis C virus infection (HCV) and one case each for hairy cell leukemia (HCL) and Sezary syndrome. (3) There were no cases reported for polycythemia vera (PV) or lymphoma. (4) Sex distribution was nearly equivalent with the exception in patients with multiple sclerosis where there was female predominance (12 of 16 with reported data). (5) For pooled analysis, the average duration of treatment with IFN before TMA was diagnosed was 40.4 months. (6) Comparative analysis showed that patients with MS required the highest cumulative dose exposure before developing TMA (MS 68.6 months, CML 35.5 months, HCV 30.4 months). (7) Cases of confirmed TTP (where A disintegrin and Metalloprotease with thrombospondin type 1 motif 13: ADAMTS 13 level was measured) showed presence of an inhibitor. (8) In all cases of confirmed TTP, moderate to severe thrombocytopenia was a striking clinical feature at presentation while this was not a consistent finding in all other cases of TMA. (9) Outcome analysis revealed complete remission in 27 (40%), persistent chronic kidney disease (CKD) in 28 (42%) and fatality in 12 patients (18%). (10) Treatment with corticosteroids, plasma exchange and rituximab resulted in durable responses.
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Affiliation(s)
- Ajay Kundra
- Division of Hematology/Oncology, Brookdale University Hospital Medical Center, Brooklyn, NY, USA
| | - Jen Chin Wang
- Division of Hematology/Oncology, Brookdale University Hospital Medical Center, Brooklyn, NY, USA.
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Short-term culture of monocytes as an in vitro evaluation system for bionanomaterials designated for medical use. Food Chem Toxicol 2016; 96:302-8. [DOI: 10.1016/j.fct.2016.08.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 08/18/2016] [Accepted: 08/19/2016] [Indexed: 02/07/2023]
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Crosbie PAJ, Crosbie EJ, Aspinall-O'Dea M, Walker M, Harrison R, Pernemalm M, Shah R, Joseph L, Booton R, Pierce A, Whetton AD. ERK and AKT phosphorylation status in lung cancer and emphysema using nanocapillary isoelectric focusing. BMJ Open Respir Res 2016; 3:e000114. [PMID: 26918193 PMCID: PMC4762086 DOI: 10.1136/bmjresp-2015-000114] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 01/02/2016] [Accepted: 01/04/2016] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Emphysema is an independent risk factor for the development of lung cancer in smokers. Activation of oncogenic signalling proteins AKT and ERK by phosphorylation has an established role in the development of lung cancer and has also been implicated in the pathogenesis of emphysema. The aim of this study was to compare the protein level and phosphorylation status of AKT and ERK in paired lung cancer and emphysema tissue using a highly sensitive phosphoprotein analysis approach. METHODS An antibody-based, nanocapillary isoelectric focusing (cIEF) assay was used to determine the relative quantities and phosphorylation status of AKT and ERK in tumour and matched lung tissue from patients, with or without evidence of emphysema, undergoing curative resection for non-small cell lung cancer. RESULTS 20 patients with adenocarcinoma (n=9) or squamous cell carcinoma (n=11) of the lung were included (mean age 67.3 years (SD 7.5, range 47-80 years)), 12 were men and all were current (n=10) or former smokers (n=10). Paired macroscopically normal lung tissue was either histologically normal (n=7) or showed emphysema (n=13). Total and phosphorylated AKT levels were fourfold (p=0.0001) and fivefold (p=0.001) higher in tumour compared with matched lung, respectively. There was no correlation with tumour histology, stage or differentiation; however, total AKT signal in tumour was significantly correlated with fluorodeoxyglucose avidity on positron emission tomography-CT scan (r=0.53, p=0.035). Total ERK was not differentially expressed, but doubly phosphorylated (activated) ERK was threefold higher in emphysema (23.5%, SD 9.2) than either matched tumour (8.8%, SD 8.6) or normal lung tissue (8.3%, SD 9.0) and correlated with the histological severity of emphysema (p=0.005). CONCLUSIONS cIEF offers opportunities for quantifying subtle shifts in the phosphorylation status of oncoproteins in nanogram amounts of lung tissue. ERK activation is a feature of emphysema.
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Affiliation(s)
- Philip A J Crosbie
- North West Lung Centre, University Hospital of South Manchester, Manchester, UK; Stem Cell and Leukaemia Proteomics Laboratory, University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Emma J Crosbie
- Institute of Cancer Sciences, University of Manchester, St Mary's Hospital , Manchester , UK
| | - Mark Aspinall-O'Dea
- Stem Cell and Leukaemia Proteomics Laboratory , University of Manchester, Manchester Academic Health Science Centre , Manchester , UK
| | - Michael Walker
- Stem Cell and Leukaemia Proteomics Laboratory , University of Manchester, Manchester Academic Health Science Centre , Manchester , UK
| | - Rebecca Harrison
- Manchester Medical School, University of Manchester , Manchester , UK
| | - Maria Pernemalm
- Department of Oncology and Pathology , Karolinska Institutet, SciLifeLab , Stockholm , Sweden
| | - Rajesh Shah
- Department of Thoracic Surgery , University Hospital of South Manchester , Manchester , UK
| | - Leena Joseph
- Department of Pathology , University Hospital of South Manchester , Manchester , UK
| | - Richard Booton
- North West Lung Centre, University Hospital of South Manchester , Manchester , UK
| | - Andrew Pierce
- Stem Cell and Leukaemia Proteomics Laboratory , University of Manchester, Manchester Academic Health Science Centre , Manchester , UK
| | - Anthony D Whetton
- Stem Cell and Leukaemia Proteomics Laboratory , University of Manchester, Manchester Academic Health Science Centre , Manchester , UK
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Antibody-based detection of protein phosphorylation status to track the efficacy of novel therapies using nanogram protein quantities from stem cells and cell lines. Nat Protoc 2014; 10:149-68. [PMID: 25521791 DOI: 10.1038/nprot.2015.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
This protocol describes a highly reproducible antibody-based method that provides protein level and phosphorylation status information from nanogram quantities of protein cell lysate. Nanocapillary isoelectric focusing (cIEF) combines with UV-activated linking chemistry to detect changes in phosphorylation status. As an example application, we describe how to detect changes in response to tyrosine kinase inhibitors (TKIs) in the phosphorylation status of the adaptor protein CrkL, a major substrate of the oncogenic tyrosine kinase BCR-ABL in chronic myeloid leukemia (CML), using highly enriched CML stem cells and mature cell populations in vitro. This protocol provides a 2.5 pg/nl limit of protein detection (<0.2% of a stem cell sample containing <10(4) cells). Additional assays are described for phosphorylated tyrosine 207 (pTyr207)-CrkL and the protein tyrosine phosphatase PTPRC/CD45; these assays were developed using this protocol and applied to CML patient samples. This method is of high throughput, and it can act as a screen for in vitro cancer stem cell response to drugs and novel agents.
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