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Pontifex CS, Zaman M, Fanganiello RD, Shutt TE, Pfeffer G. Valosin-Containing Protein (VCP): A Review of Its Diverse Molecular Functions and Clinical Phenotypes. Int J Mol Sci 2024; 25:5633. [PMID: 38891822 PMCID: PMC11172259 DOI: 10.3390/ijms25115633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 05/20/2024] [Accepted: 05/20/2024] [Indexed: 06/21/2024] Open
Abstract
In this review we examine the functionally diverse ATPase associated with various cellular activities (AAA-ATPase), valosin-containing protein (VCP/p97), its molecular functions, the mutational landscape of VCP and the phenotypic manifestation of VCP disease. VCP is crucial to a multitude of cellular functions including protein quality control, endoplasmic reticulum-associated degradation (ERAD), autophagy, mitophagy, lysophagy, stress granule formation and clearance, DNA replication and mitosis, DNA damage response including nucleotide excision repair, ATM- and ATR-mediated damage response, homologous repair and non-homologous end joining. VCP variants cause multisystem proteinopathy, and pathology can arise in several tissue types such as skeletal muscle, bone, brain, motor neurons, sensory neurons and possibly cardiac muscle, with the disease course being challenging to predict.
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Affiliation(s)
- Carly S. Pontifex
- Hotchkiss Brain Institute, Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada; (C.S.P.); (M.Z.); (T.E.S.)
| | - Mashiat Zaman
- Hotchkiss Brain Institute, Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada; (C.S.P.); (M.Z.); (T.E.S.)
- Alberta Child Health Research Institute, Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB T2N 1N4, Canada
| | | | - Timothy E. Shutt
- Hotchkiss Brain Institute, Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada; (C.S.P.); (M.Z.); (T.E.S.)
- Alberta Child Health Research Institute, Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Gerald Pfeffer
- Hotchkiss Brain Institute, Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada; (C.S.P.); (M.Z.); (T.E.S.)
- Alberta Child Health Research Institute, Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada
- Heritage Medical Research Building 155, 3330 Hospital Dr NW, Calgary, AB T2N 4N1, Canada
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He J, Zhou Y, Sun L. Emerging mechanisms of the unfolded protein response in therapeutic resistance: from chemotherapy to Immunotherapy. Cell Commun Signal 2024; 22:89. [PMID: 38297380 PMCID: PMC10832166 DOI: 10.1186/s12964-023-01438-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Accepted: 12/12/2023] [Indexed: 02/02/2024] Open
Abstract
The accumulation of unfolded or misfolded proteins in the endoplasmic reticulum (ER) causes ER stress and activates the unfolded protein response (UPR). As an adaptive cellular response to hostile microenvironments, such as hypoxia, nutrient deprivation, oxidative stress, and chemotherapeutic drugs, the UPR is activated in diverse cancer types and functions as a dynamic tumour promoter in cancer development; this role of the UPR indicates that regulation of the UPR can be utilized as a target for tumour treatment. T-cell exhaustion mainly refers to effector T cells losing their effector functions and expressing inhibitory receptors, leading to tumour immune evasion and the loss of tumour control. Emerging evidence suggests that the UPR plays a crucial role in T-cell exhaustion, immune evasion, and resistance to immunotherapy. In this review, we summarize the molecular basis of UPR activation, the effect of the UPR on immune evasion, the emerging mechanisms of the UPR in chemotherapy and immunotherapy resistance, and agents that target the UPR for tumour therapeutics. An understanding of the role of the UPR in immune evasion and therapeutic resistance will be helpful to identify new therapeutic modalities for cancer treatment. Video Abstract.
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Affiliation(s)
- Jiang He
- Xiangya Cancer Center, Xiangya Hospital, Central South University, Changsha, 410008, China.
- Key Laboratory of Molecular Radiation Oncology Hunan Province, Changsha, 410008, China.
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Changsha, 410008, Huan, China.
- Hunan International Science and Technology Collaboration Base of Precision Medicine for Cancer, Changsha, 410008, China.
- Center for Molecular Imaging of Central, South University, Xiangya Hospital, Changsha, 410008, China.
| | - You Zhou
- Department of Pathology, Tongji Medical College Union Hospital, Huazhong University of Science and Technology, Wuhan, 430022, China
| | - Lunquan Sun
- Xiangya Cancer Center, Xiangya Hospital, Central South University, Changsha, 410008, China.
- Key Laboratory of Molecular Radiation Oncology Hunan Province, Changsha, 410008, China.
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Changsha, 410008, Huan, China.
- Hunan International Science and Technology Collaboration Base of Precision Medicine for Cancer, Changsha, 410008, China.
- Center for Molecular Imaging of Central, South University, Xiangya Hospital, Changsha, 410008, China.
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Hernández-Suárez B, Gillespie DA, Obmińska-Mrukowicz B, Pawlak A. An initial characterisation of the Unfolded Protein Response pathway in haematopoietic canine cancer cell lines - a necessary step for the future development of new therapies in dogs with neoplasia. J Vet Res 2023; 67:447-458. [PMID: 37818142 PMCID: PMC10561074 DOI: 10.2478/jvetres-2023-0042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 08/02/2023] [Indexed: 10/12/2023] Open
Abstract
Introduction New and more effective therapies for canine cancer patients are urgently required and this necessitates advanced experimental research. Dogs are good models for studies in comparative oncology; however, canine cancer cell biology research is currently limited by low availability of validated antibody reagents and techniques. This study characterises the expression of key components of the unfolded protein response (UPR) in a panel of haematopoietic canine cancer cell lines using commercially available antibodies, and validates the methods used to study this pathway. Material and Methods The CLBL-1 canine lymphoma cell line and the GL-1 canine leukaemia cell line sourced externally and two counterparts established in house (CNK-89 and CLB70) were used as models of different lymphoma and leukaemia canine cell lines for the study. The human U2OS cell line served as the control. Antibodies were selected for identifying UPR proteins according to known canine cell reactivity and canine-murine and canine-human homology. Endoplasmic reticulum stress was induced with thapsigargin and MG132 in the cell lines. Etoposide was used to induce DNA damage in the cells. The techniques used for this validation analysis were RNA sequencing to observe the expression of UPR components in canine cell lines, Western blot to observe changes of protein expression levels after inducing ER stress in the cells, and flow cytometry in order to study cell death. Results Substantial variations in both the basic expression and agonist-induced activation of the UPR pathway were observed in canine cancer cell lines, although the biological significance of these differences requires further investigation. Conclusion These findings will be a starting point for future studies on cancer biology in dogs. They will also contribute to developing novel anticancer therapies for canine patients and may provide new insights into human oncology.
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Affiliation(s)
- Beatriz Hernández-Suárez
- Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences, 50-375Wrocław, Poland
| | - David A. Gillespie
- Instituto de Tecnologías Biomédicas, Facultad de Medicina, Campus Ciencias de la Salud, Universidad de La Laguna, La Laguna38071, Tenerife, Spain
| | - Bożena Obmińska-Mrukowicz
- Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences, 50-375Wrocław, Poland
| | - Aleksandra Pawlak
- Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, Wrocław University of Environmental and Life Sciences, 50-375Wrocław, Poland
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Hernández-Suárez B, Gillespie DA, Dejnaka E, Kupczyk P, Obmińska-Mrukowicz B, Pawlak A. Studying the DNA damage response pathway in hematopoietic canine cancer cell lines, a necessary step for finding targets to generate new therapies to treat cancer in dogs. Front Vet Sci 2023; 10:1227683. [PMID: 37655260 PMCID: PMC10467447 DOI: 10.3389/fvets.2023.1227683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 07/31/2023] [Indexed: 09/02/2023] Open
Abstract
Background Dogs present a significant opportunity for studies in comparative oncology. However, the study of cancer biology phenomena in canine cells is currently limited by restricted availability of validated antibody reagents and techniques. Here, we provide an initial characterization of the expression and activity of key components of the DNA Damage Response (DDR) in a panel of hematopoietic canine cancer cell lines, with the use of commercially available antibody reagents. Materials and methods The techniques used for this validation analysis were western blot, qPCR, and DNA combing assay. Results Substantial variations in both the basal expression (ATR, Claspin, Chk1, and Rad51) and agonist-induced activation (p-Chk1) of DDR components were observed in canine cancer cell lines. The expression was stronger in the CLBL-1 (B-cell lymphoma) and CLB70 (B-cell chronic lymphocytic leukemia) cell lines than in the GL-1 (B-cell leukemia) cell line, but the biological significance of these differences requires further investigation. We also validated methodologies for quantifying DNA replication dynamics in hematopoietic canine cancer cell lines, and found that the GL-1 cell line presented a higher replication fork speed than the CLBL-1 cell line, but that both showed a tendency to replication fork asymmetry. Conclusion These findings will inform future studies on cancer biology, which will facilitate progress in developing novel anticancer therapies for canine patients. They can also provide new knowledge in human oncology.
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Affiliation(s)
- Beatriz Hernández-Suárez
- Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, Wrocław, Poland
| | - David A. Gillespie
- Facultad de Medicina, Instituto de Tecnologías Biomédicas, Universidad de La Laguna, Tenerife, Spain
| | - Ewa Dejnaka
- Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, Wrocław, Poland
| | - Piotr Kupczyk
- Division of General and Experimental Pathology, Department of Clinical and Experimental Pathology, Faculty of Medicine, Wroclaw Medical University, Wroclaw, Poland
| | - Bożena Obmińska-Mrukowicz
- Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, Wrocław, Poland
| | - Aleksandra Pawlak
- Department of Pharmacology and Toxicology, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, Wrocław, Poland
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Huang S, Lu Y, Li S, Zhou T, Wang J, Xia J, Zhang X, Zhou Z. Key proteins of proteome underlying sperm malformation of rats exposed to low fenvalerate doses are highly related to P53. ENVIRONMENTAL TOXICOLOGY 2021; 36:1181-1194. [PMID: 33656234 DOI: 10.1002/tox.23117] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 02/19/2021] [Indexed: 06/12/2023]
Abstract
Fenvalerate (Fen) is an endocrine disruptor, capable of interfering with the activity of estrogen and androgen. Our objective was to explore the molecular mechanisms of Fen on sperm in vivo. Adult male Sprague-Dawley rats were orally exposed to 0, 0.00625, 0.125, 2.5, 30 mg/kg/day Fen for 8 weeks. Sperm morphology, differential proteomics of sperm and testes, bioinformatic analysis, western blotting (WB), and RT-PCR were used to explore the mechanism of Fen on sperm. Data showed that low Fen doses significantly induced sperm malformations. In sperm proteomics, 47 differentially expressed (DE) proteins were enriched in biological processes (BPs) related to energy metabolism, response to estrogen, spermatogenesis; and enriched in cellular components (CCs) relating to energy-metabolism, sperm fibrous sheath and their outer dense fibers. In testicular proteomics, 56 DE proteins were highly associated with mRNA splicing, energy metabolism; and enriched in CCs relating to vesicles, myelin sheath, microtubules, mitochondria. WB showed that the expression of selected proteins was identical to their tendency in 2D gels. Literature indicates that key DE proteins in proteomic profiles (such as Trap1, Hnrnpa2b1, Hnrnpk, Hspa8, and Gapdh) are involved in P53-related processes or morphogenesis or spermatogenesis. Also, P53 mRNA and protein levels were significantly increased by Fen; bioinformatic re-analysis showed that 88.5% DE proteins and P53 formed a complex interacting network, and the key DE proteins were coenriched with P53-related BPs. Results indicate that key DE proteins of proteome underlying sperm malformations of rats exposed to low Fen doses are highly related to P53.
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Affiliation(s)
- Shaoping Huang
- Department of Histology and Embryology, Medical School, Southeast University, Nanjing, China
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China
| | - Ying Lu
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China
- Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| | - Suying Li
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China
- Reproductive Center of Second Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Tao Zhou
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China
- Central Laboratory, Wuxi Maternity and Child Health Care Hospital Affiliated to Nanjing Medical University, Wuxi, China
| | - Jing Wang
- Zhong Da Hospital, Southeast University, Nanjing, China
| | - Jiangyan Xia
- Zhong Da Hospital, Southeast University, Nanjing, China
| | - Xinxin Zhang
- Department of Histology and Embryology, Medical School, Southeast University, Nanjing, China
| | - Zuomin Zhou
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China
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Wang X, Bai E, Zhou H, Sha S, Miao H, Qin Y, Liu Z, Wang J, Zhang H, Lei M, Liu J, Hai O, Zhu Y. Discovery of a new class of valosine containing protein (VCP/P97) inhibitors for the treatment of non-small cell lung cancer. Bioorg Med Chem 2018; 27:533-544. [PMID: 30606672 DOI: 10.1016/j.bmc.2018.12.036] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 12/19/2018] [Accepted: 12/27/2018] [Indexed: 10/27/2022]
Abstract
Valosine containing protein (VCP/p97) is a member of the AAA ATPase family involved in several essential cellular functions and plays an important role in the ubiquitin-mediated degradation of misfolded proteins. P97 has a significant role in maintaining the cellular protein homeostasis for tumor cell growth and survival and has been found overexpressed in many tumor types. No new molecule entities based on p97 target were approved in clinic. Herein, a series of novel pyrimidine structures as p97 inhibitors were designed and synthesized. After enzymatic evaluations, structure-activity relationships (SAR) were discussed in detailed. Among the screened compounds, derivative 35 showed excellent enzymatic inhibitory activity (IC50, 36 nM). The cellular inhibition results showed that compound 35 had good antiproliferative activity against the non-small cell lung cancer A549 cells (IC50, 1.61 μM). Liver microsome stability showed that the half-life of compound 35 in human liver microsome was 42.3 min, which was more stable than the control CB-5083 (25.8 min). The in vivo pharmacokinetic results showed that the elimination phase half-lives of compound 35 were 4.57 h for ig and 3.64 h for iv, respectively and the oral bioavailability was only 4.5%. These results indicated that compound 35 could be effective for intravenous treatment of non-small cell lung cancer.
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Affiliation(s)
- Xueyuan Wang
- College of Life Science, Nanjing Normal University, No. 1 Wenyuan Road, Nanjing 210037, PR China
| | - Enhe Bai
- College of Life Science, Nanjing Normal University, No. 1 Wenyuan Road, Nanjing 210037, PR China
| | - Hui Zhou
- College of Life Science, Nanjing Normal University, No. 1 Wenyuan Road, Nanjing 210037, PR China
| | - Sijia Sha
- College of Science, Nanjing Forestry University, No. 159 Longpan Road, Nanjing 210037, PR China
| | - Hang Miao
- College of Science, Nanjing Forestry University, No. 159 Longpan Road, Nanjing 210037, PR China
| | - Yanru Qin
- School of Bio-engineering, Qilu University of Technology (Shandong Academy of Sciences), No. 3501 Daxue Rd. Changqing District, Jinan 250353, PR China
| | - Zhaogang Liu
- Jiangsu Chia Tai Fenghai Pharmaceutical Co. Ltd., No. 9 Weidi Road, Nanjing 210046, PR China
| | - Jia Wang
- Jiangsu Chia Tai Fenghai Pharmaceutical Co. Ltd., No. 9 Weidi Road, Nanjing 210046, PR China
| | - Haoyang Zhang
- College of Life Science, Nanjing Normal University, No. 1 Wenyuan Road, Nanjing 210037, PR China
| | - Meng Lei
- College of Science, Nanjing Forestry University, No. 159 Longpan Road, Nanjing 210037, PR China.
| | - Jia Liu
- Jiangsu Chia Tai Fenghai Pharmaceutical Co. Ltd., No. 9 Weidi Road, Nanjing 210046, PR China
| | - Ou Hai
- Jiangsu Chia Tai Fenghai Pharmaceutical Co. Ltd., No. 9 Weidi Road, Nanjing 210046, PR China
| | - Yongqiang Zhu
- College of Life Science, Nanjing Normal University, No. 1 Wenyuan Road, Nanjing 210037, PR China.
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Salimi L, Rahbarghazi R, Jafarian V, Biray Avci Ç, Goker Bagca B, Pinar Ozates N, Khaksar M, Nourazarian A. Heat shock protein 70 modulates neural progenitor cells dynamics in human neuroblastoma SH-SY5Y cells exposed to high glucose content. J Cell Biochem 2018; 119:6482-6491. [PMID: 29345335 DOI: 10.1002/jcb.26679] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 01/17/2018] [Indexed: 01/21/2023]
Abstract
In the current experiment, detrimental effects of high glucose condition were investigated on human neuroblastoma cells. Human neuroblastoma cell line SH-SY5Y were exposed to 5, 40, and 70 mM glucose over a period of 72 h. Survival rate and the proliferation of cells were analyzed by MTT and BrdU incorporation assays. Apoptosis was studied by the assays of flow cytometry and PCR array. In order to investigate the trans-differentiation capacity of the cell into mature neurons, we used immunofluorescence imaging to follow NeuN protein level. The transcription level of HSP70 was shown by real-time PCR analysis. MMP-2 and -9 activities were shown by gelatin Zymography. According to data from MTT and BrdU incorporation assay, 70 mM glucose reduced cell viability and proliferation rate as compared to control (5 mM glucose) and cells treated with 40 mM glucose (P < 0.05). Cell exposure to 70 mM glucose had potential to induced apoptosis after 72 h (P < 0.05). Our results also demonstrated the sensitivity of SH-SY5Y cells to detrimental effects of high glucose condition during trans-differentiation into mature neuron-like cells. Real-time PCR analysis confirmed the expression of HSP70 in cells under high content glucose levels, demonstrating the possible cell compensatory response to an insulting condition (pcontrol vs 70 mM group <0.05). Both MMP-2 and -9 activities were reduced in cells being exposed to 70 mM glucose. High glucose condition could abrogate the dynamics of neural progenitor cells. The intracellular level of HSP70 was proportional to cell damage in high glucose condition.
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Affiliation(s)
- Leila Salimi
- Department of Biology, Faculty of Sciences, University of Zanjan, Zanjan, Iran.,Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Reza Rahbarghazi
- Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Applied Cell Sciences, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Vahab Jafarian
- Department of Biology, Faculty of Sciences, University of Zanjan, Zanjan, Iran
| | - Çıgır Biray Avci
- Department of Medical Biology, Faculty of Medicine, Ege University, Izmir, Turkey
| | - Bakiye Goker Bagca
- Department of Medical Biology, Faculty of Medicine, Ege University, Izmir, Turkey
| | | | - Majid Khaksar
- Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Alireza Nourazarian
- Stem Cell Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Biochemistry and Clinical Laboratories, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
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Interplay between P-Glycoprotein Expression and Resistance to Endoplasmic Reticulum Stressors. Molecules 2018; 23:molecules23020337. [PMID: 29415493 PMCID: PMC6017601 DOI: 10.3390/molecules23020337] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Revised: 01/30/2018] [Accepted: 02/01/2018] [Indexed: 12/13/2022] Open
Abstract
Multidrug resistance (MDR) is a phenotype of cancer cells with reduced sensitivity to a wide range of unrelated drugs. P-glycoprotein (P-gp)—a drug efflux pump (ABCB1 member of the ABC transporter gene family)—is frequently observed to be a molecular cause of MDR. The drug-efflux activity of P-gp is considered as the underlying mechanism of drug resistance against P-gp substrates and results in failure of cancer chemotherapy. Several pathological impulses such as shortages of oxygen and glucose supply, alterations of calcium storage mechanisms and/or processes of protein N-glycosylation in the endoplasmic reticulum (ER) leads to ER stress (ERS), characterized by elevation of unfolded protein cell content and activation of the unfolded protein response (UPR). UPR is responsible for modification of protein folding pathways, removal of misfolded proteins by ER associated protein degradation (ERAD) and inhibition of proteosynthesis. However, sustained ERS may result in UPR-mediated cell death. Neoplastic cells could escape from the death pathway induced by ERS by switching UPR into pro survival mechanisms instead of apoptosis. Here, we aimed to present state of the art information about consequences of P-gp expression on mechanisms associated with ERS development and regulation of the ERAD system, particularly focused on advances in ERS-associated therapy of drug resistant malignancies.
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Gareau A, Rico C, Boerboom D, Nadeau ME. In vitro efficacy of a first-generation valosin-containing protein inhibitor (CB-5083) against canine lymphoma. Vet Comp Oncol 2018; 16:311-317. [PMID: 29314493 DOI: 10.1111/vco.12380] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Revised: 11/27/2017] [Accepted: 11/28/2017] [Indexed: 11/26/2022]
Abstract
Valosin-containing protein (VCP), through its critical role in the maintenance of protein homeostasis, is a promising target for the treatment of several malignancies, including canine lymphoma. CB-5083, a first-in-class VCP inhibitor, exerts cytotoxicity through the induction of irreversible proteotoxic stress and possesses a broad spectrum of anticancer activity. Here, we determined the cytotoxicity CB-5083 in canine lymphoma cells and its mechanism of action in vitro. Canine lymphoma cell lines were treated with varying concentrations of CB-5083 and assessed for viability by trypan blue exclusion and apoptosis by caspase activity assays. The mechanism of CB-5083 action was determined by immunoblotting and RT-qPCR analyses of Lys48 ubiquitination and markers of ER stress (DDIT3), autophagy (SQSTM1, MAP1LC3A) and DNA damage (γH2AX). Unfolded protein response markers were also evaluated by immunoblotting (eIF2α, P-eIF2α) and RT-qPCR (ATF4). CB-5083 treatment resulted in preferential cytotoxicity in canine lymphoma cell lines over control peripheral blood mononuclear cells. CB-5083 rapidly disrupted the ubiquitin-dependent protein degradation system, inducing sustained ER stress as indicated by a dramatic increase in DDIT3. Activation of the unfolded protein response occurred through the increase eIF2α phosphorylation and increased transcription of ATF4, but did not re-establish protein homeostasis. Cells rapidly underwent apoptosis through activation of the caspase cascade. These results further validate VCP as an attractive target for the treatment of canine lymphoma and identify CB-5083 as a novel therapy with clinical potential for this malignancy.
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Affiliation(s)
- A Gareau
- Faculté de Médecine vétérinaire, Université de Montreal, St-Hyacinthe, Québec, Canada J2C 7C6
| | - C Rico
- Faculté de Médecine vétérinaire, Université de Montreal, St-Hyacinthe, Québec, Canada J2C 7C6
| | - D Boerboom
- Faculté de Médecine vétérinaire, Université de Montreal, St-Hyacinthe, Québec, Canada J2C 7C6
| | - M-E Nadeau
- Faculté de Médecine vétérinaire, Université de Montreal, St-Hyacinthe, Québec, Canada J2C 7C6
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