1
|
Grimaldi I, Leser FS, Janeiro JM, da Rosa BG, Campanelli AC, Romão L, Lima FRS. The multiple functions of PrP C in physiological, cancer, and neurodegenerative contexts. J Mol Med (Berl) 2022; 100:1405-1425. [PMID: 36056255 DOI: 10.1007/s00109-022-02245-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 08/05/2022] [Accepted: 08/09/2022] [Indexed: 11/29/2022]
Abstract
Cellular prion protein (PrPC) is a highly conserved glycoprotein, present both anchored in the cell membrane and soluble in the extracellular medium. It has a diversity of ligands and is variably expressed in numerous tissues and cell subtypes, most notably in the central nervous system (CNS). Its importance has been brought to light over the years both under physiological conditions, such as embryogenesis and immune system homeostasis, and in pathologies, such as cancer and neurodegenerative diseases. During development, PrPC plays an important role in CNS, participating in axonal growth and guidance and differentiation of glial cells, but also in other organs such as the heart, lung, and digestive system. In diseases, PrPC has been related to several types of tumors, modulating cancer stem cells, enhancing malignant properties, and inducing drug resistance. Also, in non-neoplastic diseases, such as Alzheimer's and Parkinson's diseases, PrPC seems to alter the dynamics of neurotoxic aggregate formation and, consequently, the progression of the disease. In this review, we explore in detail the multiple functions of this protein, which proved to be relevant for understanding the dynamics of organism homeostasis, as well as a promising target in the treatment of both neoplastic and degenerative diseases.
Collapse
Affiliation(s)
- Izabella Grimaldi
- Glial Cell Biology Laboratory, Biomedical Sciences Institute, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Felipe Saceanu Leser
- Glial Cell Biology Laboratory, Biomedical Sciences Institute, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - José Marcos Janeiro
- Glial Cell Biology Laboratory, Biomedical Sciences Institute, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Bárbara Gomes da Rosa
- Glial Cell Biology Laboratory, Biomedical Sciences Institute, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Ana Clara Campanelli
- Glial Cell Biology Laboratory, Biomedical Sciences Institute, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Luciana Romão
- Cell Morphogenesis Laboratory, Biomedical Sciences Institute, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Flavia Regina Souza Lima
- Glial Cell Biology Laboratory, Biomedical Sciences Institute, Federal University of Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
| |
Collapse
|
2
|
Loh D, Reiter RJ. Melatonin: Regulation of Prion Protein Phase Separation in Cancer Multidrug Resistance. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27030705. [PMID: 35163973 PMCID: PMC8839844 DOI: 10.3390/molecules27030705] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/11/2022] [Accepted: 01/17/2022] [Indexed: 12/13/2022]
Abstract
The unique ability to adapt and thrive in inhospitable, stressful tumor microenvironments (TME) also renders cancer cells resistant to traditional chemotherapeutic treatments and/or novel pharmaceuticals. Cancer cells exhibit extensive metabolic alterations involving hypoxia, accelerated glycolysis, oxidative stress, and increased extracellular ATP that may activate ancient, conserved prion adaptive response strategies that exacerbate multidrug resistance (MDR) by exploiting cellular stress to increase cancer metastatic potential and stemness, balance proliferation and differentiation, and amplify resistance to apoptosis. The regulation of prions in MDR is further complicated by important, putative physiological functions of ligand-binding and signal transduction. Melatonin is capable of both enhancing physiological functions and inhibiting oncogenic properties of prion proteins. Through regulation of phase separation of the prion N-terminal domain which targets and interacts with lipid rafts, melatonin may prevent conformational changes that can result in aggregation and/or conversion to pathological, infectious isoforms. As a cancer therapy adjuvant, melatonin could modulate TME oxidative stress levels and hypoxia, reverse pH gradient changes, reduce lipid peroxidation, and protect lipid raft compositions to suppress prion-mediated, non-Mendelian, heritable, but often reversible epigenetic adaptations that facilitate cancer heterogeneity, stemness, metastasis, and drug resistance. This review examines some of the mechanisms that may balance physiological and pathological effects of prions and prion-like proteins achieved through the synergistic use of melatonin to ameliorate MDR, which remains a challenge in cancer treatment.
Collapse
Affiliation(s)
- Doris Loh
- Independent Researcher, Marble Falls, TX 78654, USA
- Correspondence: (D.L.); (R.J.R.)
| | - Russel J. Reiter
- Department of Cellular and Structural Biology, UT Health San Antonio, San Antonio, TX 78229, USA
- Correspondence: (D.L.); (R.J.R.)
| |
Collapse
|
3
|
Mouillet-Richard S, Ghazi A, Laurent-Puig P. The Cellular Prion Protein and the Hallmarks of Cancer. Cancers (Basel) 2021; 13:cancers13195032. [PMID: 34638517 PMCID: PMC8508458 DOI: 10.3390/cancers13195032] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 09/30/2021] [Accepted: 10/05/2021] [Indexed: 01/06/2023] Open
Abstract
Simple Summary The cellular prion protein PrPC is best known for its involvement, under its pathogenic isoform, in a group of neurodegenerative diseases. Notwithstanding, an emerging role for PrPC in various cancer-associated processes has attracted increasing attention over recent years. PrPC is overexpressed in diverse types of solid cancers and has been incriminated in various aspects of cancer biology, most notably proliferation, migration, invasion and metastasis, as well as resistance to cytotoxic agents. This article aims to provide a comprehensive overview of the current knowledge of PrPC with respect to the hallmarks of cancer, a reference framework encompassing the major characteristics of cancer cells. Abstract Beyond its causal involvement in a group of neurodegenerative diseases known as Transmissible Spongiform Encephalopathies, the cellular prion protein PrPC is now taking centre stage as an important contributor to cancer progression in various types of solid tumours. The prion cancer research field has progressively expanded in the last few years and has yielded consistent evidence for an involvement of PrPC in cancer cell proliferation, migration and invasion, therapeutic resistance and cancer stem cell properties. Most recent data have uncovered new facets of the biology of PrPC in cancer, ranging from its control on enzymes involved in immune tolerance to its radio-protective activity, by way of promoting angiogenesis. In the present review, we aim to summarise the body of literature dedicated to the study of PrPC in relation to cancer from the perspective of the hallmarks of cancer, the reference framework defined by Hanahan and Weinberg.
Collapse
Affiliation(s)
- Sophie Mouillet-Richard
- Centre de Recherche des Cordeliers, Université de Paris, INSERM, Sorbonne Université, F-75006 Paris, France; (A.G.); (P.L.-P.)
- Correspondence:
| | - Alexandre Ghazi
- Centre de Recherche des Cordeliers, Université de Paris, INSERM, Sorbonne Université, F-75006 Paris, France; (A.G.); (P.L.-P.)
| | - Pierre Laurent-Puig
- Centre de Recherche des Cordeliers, Université de Paris, INSERM, Sorbonne Université, F-75006 Paris, France; (A.G.); (P.L.-P.)
- Department of Biology, Institut du Cancer Paris CARPEM, APHP, Hôpital Européen Georges Pompidou, F-75015 Paris, France
| |
Collapse
|
4
|
Ding M, Chen Y, Lang Y, Cui L. The Role of Cellular Prion Protein in Cancer Biology: A Potential Therapeutic Target. Front Oncol 2021; 11:742949. [PMID: 34595121 PMCID: PMC8476782 DOI: 10.3389/fonc.2021.742949] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Accepted: 08/24/2021] [Indexed: 12/12/2022] Open
Abstract
Prion protein has two isoforms including cellular prion protein (PrPC) and scrapie prion protein (PrPSc). PrPSc is the pathological aggregated form of prion protein and it plays an important role in neurodegenerative diseases. PrPC is a glycosylphosphatidylinositol (GPI)-anchored protein that can attach to a membrane. Its expression begins at embryogenesis and reaches the highest level in adulthood. PrPC is expressed in the neurons of the nervous system as well as other peripheral organs. Studies in recent years have disclosed the involvement of PrPC in various aspects of cancer biology. In this review, we provide an overview of the current understanding of the roles of PrPC in proliferation, cell survival, invasion/metastasis, and stem cells of cancer cells, as well as its role as a potential therapeutic target.
Collapse
Affiliation(s)
- Manqiu Ding
- Department of Neurology, The First Hospital of Jilin University, Changchun, China
| | - Yongqiang Chen
- CancerCare Manitoba Research Institute, CancerCare Manitoba, University of Manitoba, Winnipeg, MB, Canada
| | - Yue Lang
- Department of Neurology, The First Hospital of Jilin University, Changchun, China
| | - Li Cui
- Department of Neurology, The First Hospital of Jilin University, Changchun, China
| |
Collapse
|
5
|
Jiang L, Ma Z, Ye X, Kang W, Yu J. Clinicopathological factors affecting the effect of neoadjuvant chemotherapy in patients with gastric cancer. World J Surg Oncol 2021; 19:44. [PMID: 33563277 PMCID: PMC7874458 DOI: 10.1186/s12957-021-02157-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 01/31/2021] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Neoadjuvant chemotherapy is an important part of the comprehensive treatment of advanced gastric cancer (GC). The effect of neoadjuvant chemotherapy plays a key role in the prognosis of GC patients. Pathological response can represent the effect of neoadjuvant chemotherapy. However, evidence focused on pathological response and associated clinicopathological factors in GC patients is quite little. In this retrospective study, the clinicopathological factors affecting the effect of neoadjuvant chemotherapy in GC patients were investigated, and suggestions were proposed to improve the effect of neoadjuvant chemotherapy on GC. METHODS Retrospective analysis was performed on GC patients who received radical surgery after neoadjuvant chemotherapy from February 2016 to December 2019 at Peking Union Medical College Hospital. Relevant clinicopathological data was collected to analyze the factors influencing the effect of neoadjuvant chemotherapy. Chi-square test was used for univariate analysis. Logistic regression was used for multivariate analysis. Receiver operating characteristic curve (ROC) was used to determine the cutoff value of variables which significantly influenced the effect of neoadjuvant chemotherapy. RESULTS A total of 203 GC patients were included in the study. Analyses showed that patients < 60 years old (OR = 1.840 [1.016-3.332], P = 0.044), histological type of poor differentiation or signet-ring cell carcinoma (OR = 2.606 [1.321-5.140], P = 0.006), and weight loss during neoadjuvant chemotherapy (OR = 2.110 [1.161-3.834], P = 0.014) were independent risk factors for neoadjuvant chemotherapy effect. In ROC analysis of weight change and neoadjuvant chemotherapy effect, area under the curve (AUC) was 0.593 (P = 0.024) and cutoff value of weight change was - 2.95%. Chi-square test showed that patients without weight loss during neoadjuvant chemotherapy had a higher rate of oral nutritional supplement (ONS) than patients with weight loss (P = 0.039). CONCLUSIONS Patients <60 years old, histological type of poor differentiation or signet-ring cell carcinoma, and weight loss during neoadjuvant chemotherapy were independent risk factors for neoadjuvant chemotherapy effect in GC patients. Patients with weight loss > 2.95% during neoadjuvant may have a worse chemotherapy effect. Timely nutritional support such as ONS to maintain patients' body weight is crucial for improving the effect of neoadjuvant chemotherapy.
Collapse
Affiliation(s)
- Lin Jiang
- Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 1 Shuaifuyuan, Wangfujin, Dongcheng District, Beijing, 100730, China
- Graduate School, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005, China
| | - Zhiqiang Ma
- Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 1 Shuaifuyuan, Wangfujin, Dongcheng District, Beijing, 100730, China
| | - Xin Ye
- Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 1 Shuaifuyuan, Wangfujin, Dongcheng District, Beijing, 100730, China
| | - Weiming Kang
- Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 1 Shuaifuyuan, Wangfujin, Dongcheng District, Beijing, 100730, China
| | - Jianchun Yu
- Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 1 Shuaifuyuan, Wangfujin, Dongcheng District, Beijing, 100730, China.
| |
Collapse
|
6
|
The Role of Cellular Prion Protein in Promoting Stemness and Differentiation in Cancer. Cancers (Basel) 2021; 13:cancers13020170. [PMID: 33418999 PMCID: PMC7825291 DOI: 10.3390/cancers13020170] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 12/31/2020] [Accepted: 01/03/2021] [Indexed: 02/05/2023] Open
Abstract
Simple Summary Aside from its well-established role in prion disorders, in the last decades the significance of cellular prion protein (PrPC) expression in human cancers has attracted great attention. An extensive body of work provided evidence that PrPC contributes to tumorigenesis by regulating tumor growth, differentiation, and resistance to conventional therapies. In particular, PrPC over-expression has been related to the acquisition of a malignant phenotype of cancer stem cells (CSCs) in a variety of solid tumors, encompassing pancreatic ductal adenocarcinoma, osteosarcoma, breast, gastric, and colorectal cancers, and primary brain tumors as well. According to consensus, increased levels of PrPC endow CSCs with self-renewal, proliferative, migratory, and invasive capacities, along with increased resistance to anti-cancer agents. In addition, increasing evidence demonstrates that PrPc also participates in multi-protein complexes to modulate the oncogenic properties of CSCs, thus sustaining tumorigenesis. Therefore, strategies aimed at targeting PrPC and/or PrPC-organized complexes could be a promising approach for anti-cancer therapy. Abstract Cellular prion protein (PrPC) is seminal to modulate a variety of baseline cell functions to grant homeostasis. The classic role of such a protein was defined as a chaperone-like molecule being able to rescue cell survival. Nonetheless, PrPC also represents the precursor of the deleterious misfolded variant known as scrapie prion protein (PrPSc). This variant is detrimental in a variety of prion disorders. This multi-faceted role of PrP is greatly increased by recent findings showing how PrPC in its folded conformation may foster tumor progression by acting at multiple levels. The present review focuses on such a cancer-promoting effect. The manuscript analyzes recent findings on the occurrence of PrPC in various cancers and discusses the multiple effects, which sustain cancer progression. Within this frame, the effects of PrPC on stemness and differentiation are discussed. A special emphasis is provided on the spreading of PrPC and the epigenetic effects, which are induced in neighboring cells to activate cancer-related genes. These detrimental effects are further discussed in relation to the aberrancy of its physiological and beneficial role on cell homeostasis. A specific paragraph is dedicated to the role of PrPC beyond its effects in the biology of cancer to represent a potential biomarker in the follow up of patients following surgical resection.
Collapse
|
7
|
Wiegmans AP, Saunus JM, Ham S, Lobb R, Kutasovic JR, Dalley AJ, Miranda M, Atkinson C, Foliaki ST, Ferguson K, Niland C, Johnstone CN, Lewis V, Collins SJ, Lakhani SR, Al-Ejeh F, Möller A. Secreted cellular prion protein binds doxorubicin and correlates with anthracycline resistance in breast cancer. JCI Insight 2019; 5:124092. [PMID: 30830863 DOI: 10.1172/jci.insight.124092] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Anthracyclines are amongst the most effective chemotherapeutics ever developed, but they produce grueling side-effects, serious adverse events and resistance often develops over time. We found that these compounds can be sequestered by secreted cellular Prion protein (PrPC), blocking their cytotoxic activity. This effect was dose-dependent using either cell line-conditioned medium or human serum as a source of PrPC. Genetic depletion of PrPC or inhibition of binding via chelation of ionic copper prevented the interaction and restored cytotoxic activity. This was more pronounced for doxorubicin than its epimer, epirubicin. Investigating the relevance to breast cancer management, we found that the levels of PRNP transcript in pre-treatment tumor biopsies stratified relapse-free survival after neoadjuvant treatment with anthracyclines, particularly amongst doxorubicin-treated patients with residual disease at surgery (p=2.8E-08). These data suggest that local sequestration could mediate treatment resistance. Consistent with this, tumor cell expression of PrPC protein correlated with poorer response to doxorubicin but not epirubicin in an independent cohort analyzed by immunohistochemistry, particularly soluble isoforms released into the extracellular environment by shedding (p=0.015). These findings have important potential clinical implications for frontline regimen decision-making. We suggest there is warranted utility for prognostic PrPC/PRNP assays to guide chemo-sensitization strategies that exploit an understanding of PrPC-anthracycline-copper ion complexes.
Collapse
Affiliation(s)
- Adrian P Wiegmans
- Tumor Microenvironment Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Jodi M Saunus
- Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Herston, Queensland, Australia
| | - Sunyoung Ham
- Tumor Microenvironment Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Richard Lobb
- Tumor Microenvironment Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Jamie R Kutasovic
- Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Herston, Queensland, Australia
| | - Andrew J Dalley
- Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Herston, Queensland, Australia
| | - Mariska Miranda
- Personalized Medicine Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Caroline Atkinson
- Children's Cancer Institute Australia, Lowy Cancer Research Centre, University of New South Wales, Sydney, New South Wales, Australia
| | - Simote T Foliaki
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Parkville, Victoria, Australia
| | - Kaltin Ferguson
- Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Herston, Queensland, Australia
| | - Colleen Niland
- Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Herston, Queensland, Australia
| | - Cameron N Johnstone
- Cancer and Inflammation Laboratory, Olivia Newton-John Cancer Research Institute, Heidelberg, Victoria, Australia
| | - Victoria Lewis
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Parkville, Victoria, Australia
| | - Steven J Collins
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Parkville, Victoria, Australia
| | - Sunil R Lakhani
- Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Herston, Queensland, Australia.,Pathology Queensland, The Royal Brisbane and Women's Hospital, Herston, Queensland, Australia
| | - Fares Al-Ejeh
- Personalized Medicine Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| | - Andreas Möller
- Tumor Microenvironment Laboratory, QIMR Berghofer Medical Research Institute, Herston, Queensland, Australia
| |
Collapse
|
8
|
Prion Protein Family Contributes to Tumorigenesis via Multiple Pathways. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1018:207-224. [PMID: 29052140 DOI: 10.1007/978-981-10-5765-6_13] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A wealth of evidence suggests that proteins from prion protein (PrP) family contribute to tumorigenesis in many types of cancers, including pancreatic ductal adenocarcinoma (PDAC), breast cancer, glioblastoma, colorectal cancer, gastric cancer, melanoma, etc. It is well documented that PrP is a biomarker for PDAC, breast cancer, and gastric cancer. However, the underlying mechanisms remain unclear. The major reasons for cancer cell-caused patient death are metastasis and multiple drug resistance, both of which connect to physiological functions of PrP expressing in cancer cells. PrP enhances tumorigenesis by multiple pathways. For example, PrP existed as pro-PrP in most of the PDAC cell lines, thus increasing cancer cell motility by binding to cytoskeletal protein filamin A (FLNa). Using PDAC cell lines BxPC-3 and AsPC-1 as model system, we identified that dysfunction of glycosylphosphatidylinositol (GPI) anchor synthesis machinery resulted in the biogenesis of pro-PrP. In addition, in cancer cells without FLNa expression, pro-PrP can modify cytoskeleton structure by affecting cofilin/F-actin axis, thus influencing cancer cell movement. Besides pro-PrP, we showed that GPI-anchored unglycosylated PrP can elevate cell mobility by interacting with VEGFR2, thus stimulating cell migration under serum-free condition. Besides affecting cancer cell motility, overexpressed PrP or doppel (Dpl) in cancer cells has been shown to increase cell proliferation, multiple drug resistance, and angiogenesis, thus, proteins from PrP gene family by affecting important processes via multiple pathways for cancer cell growth exacerbating tumorigenesis.
Collapse
|
9
|
Overexpression of E2F1 in human gastric carcinoma is involved in anti-cancer drug resistance. BMC Cancer 2014; 14:904. [PMID: 25466554 PMCID: PMC4258940 DOI: 10.1186/1471-2407-14-904] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 11/27/2014] [Indexed: 12/13/2022] Open
Abstract
Background Routine chemotherapy often cannot achieve good therapeutic effects because of multidrug resistance (MDR). MDR is frequently caused by the elevated expression of the MDR1 gene encoding P-glycoprotein (P-gp). E2F1 is a frequently overexpressed protein in human tumor cells that increases the activity of the MDR1 promoter, resulting in higher P-gp levels. The upregulation of P-gp might contribute to the survival of tumor cells during chemotherapy. E2F1 confers anticancer drug resistance; however, we speculate whether E2F1 affects MDR through other pathways. This study investigated the possible involvement of E2F1 in anticancer drug resistance of gastric carcinoma in vitro and in vivo. Methods A cisplatin-resistant SGC7901/DDP gastric cancer cell line with stable overexpression of E2F1 was established. Protein expression levels of E2F1, MDR1, MRP, TAp73, GAX, ZEB1, and ZEB2 were detected by western blotting. The influence of overexpression of E2F1 on anticancer drug resistance was assessed by measuring IC50 of SGC7901/DDP cells to cisplatin, doxorubicin, and 5-fluorouracil, as well as the rate of doxorubicin efflux, apoptosis, and cell cycle progression detected by flow cytometry. We determined the in vivo effects of E2F1-overexpression on tumor size in nude mice, and apoptotic cells in tumor tissues were detected by deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling and hematoxylin and eosin staining. Results The SGC7901/DDP gastric cancer cell line stably overexpressing E2F1 exhibited significantly inhibited sensitivity to cisplatin, doxorubicin, and 5-fluorouracil. Flow cytometry confirmed that the percentage of apoptotic cells decreased after E2F1 upregulation, and that upregulation of E2F1 potentiated S phase arrest of the cell cycle. Furthermore, upregulation of E2F1 significantly decreased intracellular accumulation of doxorubicin. Western blot revealed that E2F1 upregulation suppressed expression of GAX, and increased the expression of MDR1, MRP, ZEB1, TAp73, and ZEB2. Conclusions Overexpression of E2F1 promotes the development of MDR in gastric carcinoma, suggesting that E2F1 may represent an efficacious target for gastric cancer therapy.
Collapse
|
10
|
Yan LH, Wang XT, Yang J, Kong FB, Lian C, Wei WY, Luo W, Xie YB, Xiao Q. Reversal of multidrug resistance in gastric cancer cells by E2F-1 downregulation in vitro and in vivo. J Cell Biochem 2014; 115:34-41. [PMID: 24038122 DOI: 10.1002/jcb.24652] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2013] [Accepted: 08/14/2013] [Indexed: 01/06/2023]
Abstract
UNLABELLED Transcription Factor E2F-1 plays a critical role in cell cycle regulation and other biological processes in cells. However whether or not it is involved in the multi-drug resistance (MDR) process of gastric cancer has not been fully elucidated yet. To explore the role of E2F-1 in the MDR process of gastric cancer in vitro and in vivo, a cisplatin-resistant gastric cancer cell line with stable downregulation of E2F-1 was established. E2F-1 shRNA led to downregulation of endogenous E2F-1 mRNA and protein. It significantly promoted the sensitivity of SGC7901/DDP cells to cisplatin, doxorubicin, and fluorouracil. Flow cytometry confirmed that the percentage of apoptotic cells increased after E2F-1 downregulation. This notion was further supported by the observation that downregulation of E2F-1 blocked entry into the S-phase of the cell cycle. Furthermore, downregulation of E2F-1 significantly increased intracellular accumulation of doxorubicin. In addition, we determined the in vivo effects of E2F-1 small interfering RNA (shRNA) on tumor size, and apoptotic cells in tumor tissues were detected by deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling and hematoxylin and eosin staining. In molecular studies, semiquantitative RT-PCR and western blotting revealed that E2F-1 downregulation could inhibit expression of MDR1, MRP, Bcl-2/Bax, c-Myc, Skp2, Survivin, and Cyclin D1. IN CONCLUSION E2F-1 may be involved in regulating multiple signaling pathways in reversing MDR, suggesting that E2F-1 may represent a novel target for gastric cancer therapy.
Collapse
Affiliation(s)
- Lin-Hai Yan
- Department of Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, 530021, Guangxi Zhuang Autonomous Region, China
| | | | | | | | | | | | | | | | | |
Collapse
|