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Moore KM, Cerqueira V, MacLeod KG, Mullen P, Hayward RL, Green S, Harrison DJ, Cameron DA, Langdon SP. Collateral-resistance to estrogen and HER-activated growth is associated with modified AKT, ERα, and cell-cycle signaling in a breast cancer model. EXPLORATION OF TARGETED ANTI-TUMOR THERAPY 2022; 3:97-116. [PMID: 35441158 PMCID: PMC7612628 DOI: 10.37349/etat.2022.00074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Aim: A model of progressively endocrine-resistant breast cancer was investigated to identify changes that can occur in signaling pathways after endocrine manipulation. Methods: The MCF7 breast cancer model is sensitive to estrogens and anti-estrogens while variant lines previously derived from wild-type MCF7 are either relatively 17β-estradiol (E2
)-insensitive (LCC1) or fully resistant to estrogen and anti-estrogens (LCC9). Results: In LCC1 and LCC9 cell lines, loss of estrogen sensitivity was accompanied by loss of growth response to transforming growth factor alpha (TGFα), heregulin-beta and pertuzumab. LCC1 and LCC9 cells had enhanced AKT phosphorylation relative to MCF7 which was reflected in downstream activation of phospho-mechanistic target of rapamycin (mTOR), phospho-S6, and phospho-estrogen receptor alpha Ser167 [ERα(Ser167)]. Both AKT2 and AKT3 were phosphorylated in the resistant cell lines, but small interfering RNA (siRNA) knockdown suggested that all three AKT isoforms contributed to growth response. ERα(Ser118) phosphorylation was increased by E2 and TGFα in MCF7, by E2 only in LCC1, but by neither in LCC9 cells. Multiple alterations in E2-mediated cell cycle control were identified in the endocrine-resistant cell lines including increased expression of MYC, cyclin A1, cyclin D1, cyclin-dependent kinase 1 (CDK1), CDK2, and hyperphosphorylated retinoblastoma protein (ppRb), whereas p21 and p27 were reduced. Estrogen modulated expression of these regulators in MCF7 and LCC1 cells but not in LCC9 cells. Seliciclib inhibited CDK2 activation in MCF7 cells but not in resistant variants; in all lines, it reduced ppRb, increased p53 associated responses including p21, p53 up-regulated modulator of apoptosis (PUMA), and p53 apoptosis-inducing protein 1 (p53AIP1), inhibited growth, and produced G2/M block and apoptosis. Conclusions: Multiple changes occur with progression of endocrine resistance in this model with AKT activation contributing to E2 insensitivity and loss of ERα(Ser118) phosphorylation being associated with full resistance. Cell cycle regulation is modified in endocrine-resistant breast cancer cells, and seliciclib is effective in both endocrine-sensitive and resistant diseases.
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Affiliation(s)
- Kate M. Moore
- 1Cancer Research UK Edinburgh Centre, Institute of Genetics and Cancer, University of Edinburgh, Crewe Road South, EH4 2XR Edinburgh, UK 2Cancer Research UK Barts Centre, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, EC1M 6BQ London, UK
| | - Vera Cerqueira
- 1Cancer Research UK Edinburgh Centre, Institute of Genetics and Cancer, University of Edinburgh, Crewe Road South, EH4 2XR Edinburgh, UK 3West of Scotland Clinical Genetics Service, Queen Elizabeth University Hospital, G51 4TF Glasgow, UK
| | - Kenneth G. MacLeod
- 1Cancer Research UK Edinburgh Centre, Institute of Genetics and Cancer, University of Edinburgh, Crewe Road South, EH4 2XR Edinburgh, UK
| | - Peter Mullen
- 4School of Medicine, University of St Andrews, North Haugh, KY16 9TF St Andrews, UK
| | - Richard L. Hayward
- 1Cancer Research UK Edinburgh Centre, Institute of Genetics and Cancer, University of Edinburgh, Crewe Road South, EH4 2XR Edinburgh, UK
| | - Simon Green
- 5Cyclacel Ltd, James Lindsay Place, Dundee Technopole, DD1 5JJ Dundee, UK
| | - David J. Harrison
- 4School of Medicine, University of St Andrews, North Haugh, KY16 9TF St Andrews, UK
| | - David A. Cameron
- 1Cancer Research UK Edinburgh Centre, Institute of Genetics and Cancer, University of Edinburgh, Crewe Road South, EH4 2XR Edinburgh, UK
| | - Simon P. Langdon
- 1Cancer Research UK Edinburgh Centre, Institute of Genetics and Cancer, University of Edinburgh, Crewe Road South, EH4 2XR Edinburgh, UK
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Liu SS, Li Y, Zhang H, Zhang D, Zhang XB, Wang X, Yu Y. The ERα-miR-575-p27 feedback loop regulates tamoxifen sensitivity in ER-positive Breast Cancer. Theranostics 2020; 10:10729-10742. [PMID: 32929377 PMCID: PMC7482812 DOI: 10.7150/thno.46297] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 08/16/2020] [Indexed: 12/12/2022] Open
Abstract
Background: Breast cancer is the most common malignancy, and approximately 70% of breast cancers are estrogen receptor-α (ERα) positive. The anti-estrogen tamoxifen is a highly effective and commonly used treatment for patients with ER+ breast cancer. However, 30% of breast cancer patients fail adjuvant tamoxifen therapy and most of metastatic breast cancer patients develop tamoxifen resistance. Although increasing evidence suggests that microRNA (miRNA) dysregulation influences tamoxifen sensitivity, the mechanism of the cross-talk between miRNA and ERα signaling remains unclear. miR-575 has been reported to be involved in carcinogenesis and progression, however, the role of miR-575 in breast cancer remains limited. The aim of this study was to understand the mechanism of miR-575 in breast cancer tamoxifen resistance. Method: RT-qPCR was employed to assess miR-575 expression in breast cancer tissues and cell lines. The association of miR-575 expression with overall survival in patients with breast cancer was evaluated with KM plotter. Additionally, the effects of miR-575 on breast cancer proliferation and tamoxifen sensitivity were investigated both in vitro and in vivo. Bioinformatic analyses and luciferase reporter assays were performed to validate CDKN1B and BRCA1 as direct targets of miR-31-5p. The ERα binding sites in the miR-575 promoter region was validated with ChIP and luciferase assays. ERα interactions with CDKN1B, cyclin D1 or BRCA1 were determined by IP analysis, and protein expression levels and localization were analyzed by western blotting and immunofluorescence, respectively. Results: miR-575 levels were higher in ER+ breast cancer than in ER- breast cancer and patients with high miR-575 expression had a significantly poorer outcome than those with low miR-575 expression. ERα bound the miR-575 promoter to activate its transcription, and tamoxifen treatment downregulated miR-575 expression in ER+ breast cancer. Overexpression of miR-575 decreased tamoxifen sensitivity by targeting CDKN1B and BRCA1. CDKN1B and BRCA1 were both able to antagonize ERα activity by inhibiting ERα nuclear translocation and interaction with cyclin D1. Furthermore, miR-575 expression was found to be upregulated in ER+ breast cancer cell with acquired tamoxifen resistance, whereas depletion of miR-575 partially re-sensitized these cells to tamoxifen by regulation of CDKN1B. Conclusions: Our data reveal the ERα-miR-575-CDKN1B feedback loop in ER+ breast cancer, suggesting that miR-575 can be used as a prognostic biomarker in patients with ER+ breast cancer, as well as a predictor or a promising target for tamoxifen sensitivity.
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Yumimoto K, Yamauchi Y, Nakayama KI. F-Box Proteins and Cancer. Cancers (Basel) 2020; 12:cancers12051249. [PMID: 32429232 PMCID: PMC7281081 DOI: 10.3390/cancers12051249] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 05/09/2020] [Accepted: 05/12/2020] [Indexed: 12/20/2022] Open
Abstract
Controlled protein degradation is essential for the operation of a variety of cellular processes including cell division, growth, and differentiation. Identification of the relations between ubiquitin ligases and their substrates is key to understanding the molecular basis of cancer development and to the discovery of novel targets for cancer therapeutics. F-box proteins function as the substrate recognition subunits of S-phase kinase-associated protein 1 (SKP1)−Cullin1 (CUL1)−F-box protein (SCF) ubiquitin ligase complexes. Here, we summarize the roles of specific F-box proteins that have been shown to function as tumor promoters or suppressors. We also highlight proto-oncoproteins that are targeted for ubiquitylation by multiple F-box proteins, and discuss how these F-box proteins are deployed to regulate their cognate substrates in various situations.
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4
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Yamauchi Y, Nita A, Nishiyama M, Muto Y, Shimizu H, Nakatsumi H, Nakayama KI. Skp2 contributes to cell cycle progression in trophoblast stem cells and to placental development. Genes Cells 2020; 25:427-438. [PMID: 32267063 DOI: 10.1111/gtc.12769] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 03/27/2020] [Accepted: 03/27/2020] [Indexed: 12/29/2022]
Abstract
All trophoblast subtypes of the placenta are derived from trophoblast stem cells (TSCs). TSCs have the capacity to self-renew, but how the proliferation of these cells is regulated in the undifferentiated state has been largely unclear. We now show that the F-box protein Skp2 regulates the proliferation of TSCs and thereby plays a pivotal role in placental development in mice on the C57BL/6 background. The placenta of Skp2-/- mouse embryos on the C57BL/6 background was smaller than that of their Skp2+/+ littermates, with the mutant embryos also manifesting intrauterine growth retardation. Although the Skp2-/- mice were born alive, most of them died before postnatal day 21, presumably as a result of placental defects. Depletion of Skp2 in TSCs cultured in the undifferentiated state resulted in a reduced rate of proliferation and arrest of the cell cycle in G1 phase, indicative of a defect in self-renewal capacity. The cell cycle arrest apparent in Skp2-deficient TSCs was reversed by additional ablation of the cyclin-dependent kinase inhibitor (CKI) p57 but not by that of the CKI p27. Our results thus suggest that Skp2-mediated degradation of p57 is an important determinant of the self-renewal capacity of TSCs during placental development, at least in mice of certain genetic backgrounds.
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Affiliation(s)
- Yuhei Yamauchi
- Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Fukuoka, Japan
| | - Akihiro Nita
- Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Fukuoka, Japan
| | - Masaaki Nishiyama
- Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Fukuoka, Japan
| | - Yoshiharu Muto
- Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Fukuoka, Japan
| | - Hideyuki Shimizu
- Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Fukuoka, Japan
| | - Hirokazu Nakatsumi
- Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Fukuoka, Japan
| | - Keiichi I Nakayama
- Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Fukuoka, Japan
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5
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Cell cycle-dependent localization of the proteasome to chromatin. Sci Rep 2020; 10:5801. [PMID: 32242037 PMCID: PMC7118148 DOI: 10.1038/s41598-020-62697-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 03/12/2020] [Indexed: 11/08/2022] Open
Abstract
An integrative understanding of nuclear events including transcription in normal and cancer cells requires comprehensive and quantitative measurement of protein dynamics that underlie such events. However, the low abundance of most nuclear proteins hampers their detailed functional characterization. We have now comprehensively quantified the abundance of nuclear proteins with the use of proteomics approaches in both normal and transformed human diploid fibroblasts. We found that subunits of the 26S proteasome complex were markedly down-regulated in the nuclear fraction of the transformed cells compared with that of the wild-type cells. The intranuclear proteasome abundance appeared to be inversely related to the rate of cell cycle progression, with restraint of the cell cycle being associated with an increase in the amount of proteasome subunits in the nucleus, suggesting that the nuclear proteasome content is dependent on the cell cycle. Furthermore, chromatin enrichment for proteomics (ChEP) analysis revealed enrichment of the proteasome in the chromatin fraction of quiescent cells and its apparent dissociation from chromatin in transformed cells. Our results thus suggest that translocation of the nuclear proteasome to chromatin may play an important role in control of the cell cycle and oncogenesis through regulation of chromatin-associated transcription factors.
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6
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Yan Y, Allweiss L, Yang D, Kang J, Wang J, Qian X, Zhang T, Liu H, Wang L, Liu S, Sui J, Chen X, Dandri M, Zhao J, Lu F. Down-regulation of cell membrane localized NTCP expression in proliferating hepatocytes prevents hepatitis B virus infection. Emerg Microbes Infect 2019; 8:879-894. [PMID: 31179847 PMCID: PMC6567113 DOI: 10.1080/22221751.2019.1625728] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Hepatocyte proliferation could result in the loss of covalently closed circular DNA (cccDNA) and the emergence of cccDNA-cleared nascent hepatocytes, which appear refractory to hepatitis B virus (HBV) reinfection with unknown mechanism(s). Sodium taurocholate cotransporting polypeptide (NTCP) is the functional receptor for HBV entry. In this study, down-regulation of cell membrane localized NTCP expression in proliferating hepatocytes was found to prevent HBV infection in HepG2-NTCP-tet cells and in liver-humanized mice. In patients, lower NTCP protein expression was correlated well with higher levels of hepatocyte proliferation and less HBsAg expression in HBV-related focal nodular hyperplasia (FNH) tissues. Clinically, significantly lower NTCP protein expression was correlated with more active hepatocyte proliferation in CHB patients with severe active necroinflammation and better antiviral treatment outcome. Mechanistically, the activation of cell cycle regulatory genes p53, S-phase kinase-associated protein 2 (SKP2) and cyclin D1 during cell proliferation, as well as proliferative and inflammatory cytokine Interleukin-6 (IL-6) could transcriptionally down-regulate NTCP expression. From these aspects, we conclude that within the milieu of hepatocyte proliferation, down-regulation of cell membrane localized NTCP expression level renders nascent hepatocytes resistant to HBV reinfection. This may accelerate virus clearance during immune-mediated cell death and compensatory proliferation of survival hepatocytes.
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Affiliation(s)
- Ying Yan
- a State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences , Peking University Health Science Center , Beijing , People's Republic of China
| | - Lena Allweiss
- b Department of Medicine, Center for Internal Medicine , University Medical Center Hamburg-Eppendorf , Hamburg , Germany
| | - Danli Yang
- a State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences , Peking University Health Science Center , Beijing , People's Republic of China
| | - Jingting Kang
- c Institute of Basic Medical Sciences Chinese Academy of Medical Sciences , School of Basic Medicine Peking Union Medical College , Beijing , People's Republic of China
| | - Jianwen Wang
- a State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences , Peking University Health Science Center , Beijing , People's Republic of China
| | - Xiangjun Qian
- a State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences , Peking University Health Science Center , Beijing , People's Republic of China
| | - Ting Zhang
- a State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences , Peking University Health Science Center , Beijing , People's Republic of China
| | - Hui Liu
- a State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences , Peking University Health Science Center , Beijing , People's Republic of China
| | - Lu Wang
- a State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences , Peking University Health Science Center , Beijing , People's Republic of China
| | - Shuhong Liu
- d Department of Pathology and Hepatology , The 5th Medical Centre, Chinese PLA General Hospital , Beijing , People's Republic of China
| | - Jianhua Sui
- e Biologics Research Center , National Institute of Biological Sciences , Beijing , People's Republic of China
| | - Xiangmei Chen
- a State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences , Peking University Health Science Center , Beijing , People's Republic of China
| | - Maura Dandri
- b Department of Medicine, Center for Internal Medicine , University Medical Center Hamburg-Eppendorf , Hamburg , Germany.,f German Center for Infection Research (DZIF) , Hamburg-Lübeck-Borstel-Riems Partner Site , Hamburg , Germany
| | - Jingmin Zhao
- d Department of Pathology and Hepatology , The 5th Medical Centre, Chinese PLA General Hospital , Beijing , People's Republic of China
| | - Fengmin Lu
- a State Key Laboratory of Natural and Biomimetic Drugs, Department of Microbiology and Infectious Disease Center, School of Basic Medical Sciences , Peking University Health Science Center , Beijing , People's Republic of China
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7
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Sharma V, Sharma AK, Punj V, Priya P. Recent nanotechnological interventions targeting PI3K/Akt/mTOR pathway: A focus on breast cancer. Semin Cancer Biol 2019; 59:133-146. [PMID: 31408722 DOI: 10.1016/j.semcancer.2019.08.005] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Revised: 07/18/2019] [Accepted: 08/05/2019] [Indexed: 02/06/2023]
Abstract
Breast cancer is the major cause of deaths in women worldwide. Detection and treatment of breast cancer at earlier stages of the disease has shown encouraging results. Modern genomic technologies facilitated several therapeutic options however the diagnosis of the disease at an advanced stage claim more deaths. Therefore more research directed towards genomics and proteomics into this area may lead to novel biomarkers thereby enhancing the survival rates in breast cancer patients. Phosphoinositide-3-kinase/Akt/mammalian target of rapamycin (PI3K/Akt/mTOR) signaling pathway was shown to be hyperactivated in most of the breast carcinomas resulting in excessive growth, proliferation, and tumor development. Development of nanotechnology has provided many interesting avenues to target the PI3K/Akt/mTOR pathway both at the pre-clinical and clinical stages. Therefore, the current review summarizes the underlying mechanism and the importance of targeting PI3K/Akt/mTOR pathway, novel biomarkers and use of nanotechnological interventions in breast cancer.
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Affiliation(s)
- VarRuchi Sharma
- Department of Biotechnology, Maharishi Markandeshwar (Deemed to be University), Mullana-Ambala, 133207, Haryana, India
| | - Anil K Sharma
- Department of Biotechnology, Maharishi Markandeshwar (Deemed to be University), Mullana-Ambala, 133207, Haryana, India.
| | - Vasu Punj
- Department of Medicine, Keck School of Medicine, University of Southern California, LA USA
| | - Panneerselvam Priya
- Department of Electrical and Electronics Engineering, Thiruvalluvar College of Engineering and Technology, Vandavasi, 604505, Tamil Nadu, India
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Muto Y, Moroishi T, Ichihara K, Nishiyama M, Shimizu H, Eguchi H, Moriya K, Koike K, Mimori K, Mori M, Katayama Y, Nakayama KI. Disruption of FBXL5-mediated cellular iron homeostasis promotes liver carcinogenesis. J Exp Med 2019; 216:950-965. [PMID: 30877170 PMCID: PMC6446870 DOI: 10.1084/jem.20180900] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 01/15/2019] [Accepted: 02/25/2019] [Indexed: 12/17/2022] Open
Abstract
Hepatocellular iron overload elicited by ablation of the iron-sensing ubiquitin ligase FBXL5 promotes liver carcinogenesis induced by exposure to a chemical carcinogen or hepatitis virus, suggesting that FBXL5 is a previously unrecognized oncosuppressor in liver carcinogenesis in mice. Hepatic iron overload is a risk factor for progression of hepatocellular carcinoma (HCC), although the molecular mechanisms underlying this association have remained unclear. We now show that the iron-sensing ubiquitin ligase FBXL5 is a previously unrecognized oncosuppressor in liver carcinogenesis in mice. Hepatocellular iron overload elicited by FBXL5 ablation gave rise to oxidative stress, tissue damage, inflammation, and compensatory proliferation of hepatocytes and to consequent promotion of liver carcinogenesis induced by exposure to a chemical carcinogen. The tumor-promoting outcome of FBXL5 deficiency in the liver was also found to be effective in a model of virus-induced HCC. FBXL5-deficient mice thus constitute the first genetically engineered mouse model of liver carcinogenesis promoted by iron overload. In addition, dysregulation of FBXL5-mediated cellular iron homeostasis was found to be associated with poor prognosis in human HCC, suggesting that FBXL5 plays a key role in defense against hepatocarcinogenesis.
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Affiliation(s)
- Yoshiharu Muto
- Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
| | - Toshiro Moroishi
- Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
| | - Kazuya Ichihara
- Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
| | - Masaaki Nishiyama
- Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
| | - Hideyuki Shimizu
- Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
| | - Hidetoshi Eguchi
- Department of Gastroenterological Surgery, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Kyoji Moriya
- Department of Infection Control and Prevention, The University of Tokyo Hospital, Tokyo, Japan
| | - Kazuhiko Koike
- Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Koshi Mimori
- Department of Surgery, Kyushu University, Beppu Hospital, Beppu, Japan
| | - Masaki Mori
- Department of Gastroenterological Surgery, Graduate School of Medicine, Osaka University, Suita, Japan
| | - Yuta Katayama
- Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
| | - Keiichi I Nakayama
- Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
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9
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Kim JE, Kang TC. Nucleocytoplasmic p27 Kip1 Export Is Required for ERK1/2-Mediated Reactive Astroglial Proliferation Following Status Epilepticus. Front Cell Neurosci 2018; 12:152. [PMID: 29930499 PMCID: PMC5999727 DOI: 10.3389/fncel.2018.00152] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 05/16/2018] [Indexed: 01/09/2023] Open
Abstract
Reactive astrogliosis is a prominent and ubiquitous reaction of astrocytes to many types of brain injury. Up-regulation of glial fibrillary acidic protein (GFAP) expression and astroglial proliferation are hallmarks of reactive astrogliosis. However, the mechanisms that regulate reactive astrogliosis remain elusive. In the present study, status epilepticus (SE, a prolonged seizure activity) led to reactive astrogliosis showing the increases in GFAP expression and the number of proliferating astrocytes with prolonged extracellular signal receptor-activated kinases 1/2 (ERK1/2) activation and reduced nuclear p27Kip1 level. U0126, an ERK1/2 inhibitor, showed opposite effects. Leptomycin B (LMB), an inhibitor of chromosomal maintenance 1 (CRM1), attenuated nucleocytoplasmic p27Kip1 export and astroglial proliferation, although it up-regulated ERK1/2 phosphorylation and GFAP expression. Roscovitine ameliorated the reduced nuclear p27Kip1 level and astroglial proliferation without changing GFAP expression and ERK1/2 phosphorylation. U0126 aggravated SE-induced astroglial apoptosis in the molecular layer of the dentate gyrus that was unaffected by LMB and roscovitine. In addition, U0126 exacerbated SE-induced neuronal death, while LMB mitigated it. Roscovitine did not affect SE-induced neuronal death. The present data elucidate for the first time the roles of nucleocytoplasmic p27Kip1 transport in ERK1/2-mediated reactive astrogliosis independent of SE-induced neuronal death and astroglial apoptosis. Therefore, our findings suggest that nucleocytoplasmic p27Kip1 export may be required for ERK1/2-mediated astroglial proliferation during reactive astrogliosis, and that nuclear p27Kip1 entrapment may be a potential therapeutic strategy for anti-proliferation in reactive astrocytes.
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Affiliation(s)
- Ji-Eun Kim
- Department of Anatomy and Neurobiology, Institute of Epilepsy Research, College of Medicine, Hallym University, Chuncheon, South Korea
| | - Tae-Cheon Kang
- Department of Anatomy and Neurobiology, Institute of Epilepsy Research, College of Medicine, Hallym University, Chuncheon, South Korea
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10
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Hashimoto Y, Shirane M, Nakayama KI. TMEM55B contributes to lysosomal homeostasis and amino acid-induced mTORC1 activation. Genes Cells 2018; 23:418-434. [DOI: 10.1111/gtc.12583] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 03/13/2018] [Indexed: 01/28/2023]
Affiliation(s)
- Yutaka Hashimoto
- Department of Molecular and Cellular Biology; Medical Institute of Bioregulation; Kyushu University; Fukuoka Japan
| | - Michiko Shirane
- Department of Molecular and Cellular Biology; Medical Institute of Bioregulation; Kyushu University; Fukuoka Japan
- Department of Molecular Biology; Graduate School of Pharmaceutical Science; Nagoya City University; Nagoya Japan
| | - Keiichi I. Nakayama
- Department of Molecular and Cellular Biology; Medical Institute of Bioregulation; Kyushu University; Fukuoka Japan
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11
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Fujiwara D, Tsubaki M, Takeda T, Tomonari Y, Koumoto YI, Sakaguchi K, Nishida S. Statins induce apoptosis through inhibition of Ras signaling pathways and enhancement of Bim and p27 expression in human hematopoietic tumor cells. Tumour Biol 2017; 39:1010428317734947. [PMID: 28990465 DOI: 10.1177/1010428317734947] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Recently, statins have been demonstrated to improve cancer-related mortality or prognosis in patients of various cancers. However, the details of the apoptosis-inducing mechanisms remain unknown. This study showed that the induction of apoptosis by statins in hematopoietic tumor cells is mediated by mitochondrial apoptotic signaling pathways, which are activated by the suppression of mevalonate or geranylgeranyl pyrophosphate biosynthesis. In addition, statins decreased the levels of phosphorylated extracellular signal-regulated kinase 1/2 and mammalian target of rapamycin through suppressing Ras prenylation. Furthermore, inhibition of extracellular signal-regulated kinase 1/2 and mammalian target of rapamycin by statins induced Bim expression via inhibition of Bim phosphorylation and ubiquitination and cell-cycle arrest at G1 phase via enhancement of p27 expression. Moreover, combined treatment of U0126, a mitogen-activated protein kinase kinase 1/2 inhibitor, and rapamycin, a mammalian target of rapamycin inhibitor, induced Bim and p27 expressions. The present results suggested that statins induce apoptosis by decreasing the mitochondrial transmembrane potential, increasing the activation of caspase-9 and caspase-3, enhancing Bim expression, and inducing cell-cycle arrest at G1 phase through inhibition of Ras/extracellular signal-regulated kinase and Ras/mammalian target of rapamycin pathways. Therefore, our findings support the use of statins as potential anticancer agents or concomitant drugs of adjuvant therapy.
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Affiliation(s)
- Daichiro Fujiwara
- 1 Division of Pharmacotherapy, School of Pharmacy, Kindai University, Higashi-Osaka, Japan.,2 Department of Pharmacy, Japanese Red Cross Society Wakayama Medical Center, Wakayama, Japan
| | - Masanobu Tsubaki
- 1 Division of Pharmacotherapy, School of Pharmacy, Kindai University, Higashi-Osaka, Japan
| | - Tomoya Takeda
- 1 Division of Pharmacotherapy, School of Pharmacy, Kindai University, Higashi-Osaka, Japan
| | - Yoshika Tomonari
- 1 Division of Pharmacotherapy, School of Pharmacy, Kindai University, Higashi-Osaka, Japan
| | - Yu-Ichi Koumoto
- 1 Division of Pharmacotherapy, School of Pharmacy, Kindai University, Higashi-Osaka, Japan
| | - Katsuhiko Sakaguchi
- 2 Department of Pharmacy, Japanese Red Cross Society Wakayama Medical Center, Wakayama, Japan
| | - Shozo Nishida
- 1 Division of Pharmacotherapy, School of Pharmacy, Kindai University, Higashi-Osaka, Japan
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Liu C, Wang S, Zhu S, Wang H, Gu J, Gui Z, Jing J, Hou X, Shao Y. MAP3K1-targeting therapeutic artificial miRNA suppresses the growth and invasion of breast cancer in vivo and in vitro. SPRINGERPLUS 2016; 5:11. [PMID: 26759750 PMCID: PMC4700027 DOI: 10.1186/s40064-015-1597-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 12/07/2015] [Indexed: 01/11/2023]
Abstract
Recent investigations have highlighted that therapeutic artificial microRNAs could be promising candidates for cancer therapy through the modulation of tumor promoter or suppressor. MEK kinase 1 (MEKK1) is expressed by mitogen-activated kinase kinase kinase 1 (MAP3K1), an important kinase that links Ras activation to MAPK signaling. In the present study, we showed that synthetic MAP3K1-targeting artificial miRNA may provide considerable beneficial effects in the prevention of breast cancer growth and metastasis. We showed that MEKK1 was highly expressed in human breast cancer specimens, compared with adjacent normal tissues. Using a miRNA-expressing lentivirus system, we delivered a artificial miRNA (Map3k1 amiRNA) that targets MAP3K1 into 4T1 breast cancer cells and investigated the impact of MAP3K1-targeting miRNA on the growth and invasive behavior of breast cancer in vitro and in vivo. We found that overexpression of Map3k1 amiRNA led to impaired activities of p-ERK and p-p38. In addition, Map3k1 amiRNA induced marked proliferative impairment and invasive attenuation in breast cancer cells. However, Map3k1 amiRNA did not have evident influence on the apoptotic response of 4T1 cells. Moreover, using in vivo nude mice model, we identified that Map3k1 amiRNA attenuated tumor growth and lung metastasis of breast cancer cells. Taken together, our findings explicitly indicated that MEKK1 exerted important oncogenic property in breast cancer development, and MAP3K1-targeting artificial miRNA may provide promising therapeutic effects in the treatment of breast cancer.
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Affiliation(s)
- Chun Liu
- Laboratory animal center of Nantong University, 19 Qixiu Road, Nantong, Jiangsu People's Republic of China
| | - Shengjie Wang
- Kangda College of Nanjing Medical University, 88 Chunhui Road, Lianyungang, Jiangsu People's Republic of China
| | - Shunxing Zhu
- Laboratory animal center of Nantong University, 19 Qixiu Road, Nantong, Jiangsu People's Republic of China
| | - Haifeng Wang
- Kangda College of Nanjing Medical University, 88 Chunhui Road, Lianyungang, Jiangsu People's Republic of China
| | - Jiayi Gu
- Laboratory animal center of Nantong University, 19 Qixiu Road, Nantong, Jiangsu People's Republic of China
| | - Zeping Gui
- Laboratory animal center of Nantong University, 19 Qixiu Road, Nantong, Jiangsu People's Republic of China
| | - Jin Jing
- Laboratory animal center of Nantong University, 19 Qixiu Road, Nantong, Jiangsu People's Republic of China
| | - Xiaofan Hou
- Laboratory animal center of Nantong University, 19 Qixiu Road, Nantong, Jiangsu People's Republic of China
| | - Yixiang Shao
- Laboratory animal center of Nantong University, 19 Qixiu Road, Nantong, Jiangsu People's Republic of China
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13
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Linzen U, Lilischkis R, Pandithage R, Schilling B, Ullius A, Lüscher-Firzlaff J, Kremmer E, Lüscher B, Vervoorts J. ING5 is phosphorylated by CDK2 and controls cell proliferation independently of p53. PLoS One 2015; 10:e0123736. [PMID: 25860957 PMCID: PMC4393124 DOI: 10.1371/journal.pone.0123736] [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: 08/29/2014] [Accepted: 02/27/2015] [Indexed: 11/19/2022] Open
Abstract
Inhibitor of growth (ING) proteins have multiple functions in the control of cell proliferation, mainly by regulating processes associated with chromatin regulation and gene expression. ING5 has been described to regulate aspects of gene transcription and replication. Moreover deregulation of ING5 is observed in different tumors, potentially functioning as a tumor suppressor. Gene transcription in late G1 and in S phase and replication is regulated by cyclin-dependent kinase 2 (CDK2) in complex with cyclin E or cyclin A. CDK2 complexes phosphorylate and regulate several substrate proteins relevant for overcoming the restriction point and promoting S phase. We have identified ING5 as a novel CDK2 substrate. ING5 is phosphorylated at a single site, threonine 152, by cyclin E/CDK2 and cyclin A/CDK2 in vitro. This site is also phosphorylated in cells in a cell cycle dependent manner, consistent with it being a CDK2 substrate. Furthermore overexpression of cyclin E/CDK2 stimulates while the CDK2 inhibitor p27KIP1 represses phosphorylation at threonine 152. This site is located in a bipartite nuclear localization sequence but its phosphorylation was not sufficient to deregulate the subcellular localization of ING5. Although ING5 interacts with the tumor suppressor p53, we could not establish p53-dependent regulation of cell proliferation by ING5 and by phospho-site mutants. Instead we observed that the knockdown of ING5 resulted in a strong reduction of proliferation in different tumor cell lines, irrespective of the p53 status. This inhibition of proliferation was at least in part due to the induction of apoptosis. In summary we identified a phosphorylation site at threonine 152 of ING5 that is cell cycle regulated and we observed that ING5 is necessary for tumor cell proliferation, without any apparent dependency on the tumor suppressor p53.
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Affiliation(s)
- Ulrike Linzen
- Institute of Biochemistry and Molecular Biology, Medical School, RWTH Aachen University, Pauwelsstrasse 30, 52057, Aachen, Germany
| | - Richard Lilischkis
- Institute of Biochemistry and Molecular Biology, Medical School, RWTH Aachen University, Pauwelsstrasse 30, 52057, Aachen, Germany
| | - Ruwin Pandithage
- Institute of Biochemistry and Molecular Biology, Medical School, RWTH Aachen University, Pauwelsstrasse 30, 52057, Aachen, Germany
| | - Britta Schilling
- Institute of Biochemistry and Molecular Biology, Medical School, RWTH Aachen University, Pauwelsstrasse 30, 52057, Aachen, Germany
| | - Andrea Ullius
- Institute of Biochemistry and Molecular Biology, Medical School, RWTH Aachen University, Pauwelsstrasse 30, 52057, Aachen, Germany
| | - Juliane Lüscher-Firzlaff
- Institute of Biochemistry and Molecular Biology, Medical School, RWTH Aachen University, Pauwelsstrasse 30, 52057, Aachen, Germany
| | - Elisabeth Kremmer
- Helmholtz Zentrum München, Institute of Molecular Immunology, Marchioninistrasse 25, 81377, München, Germany
| | - Bernhard Lüscher
- Institute of Biochemistry and Molecular Biology, Medical School, RWTH Aachen University, Pauwelsstrasse 30, 52057, Aachen, Germany
- * E-mail: (BL); (JV)
| | - Jörg Vervoorts
- Institute of Biochemistry and Molecular Biology, Medical School, RWTH Aachen University, Pauwelsstrasse 30, 52057, Aachen, Germany
- * E-mail: (BL); (JV)
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14
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Joshi M, Rice SJ, Liu X, Miller B, Belani CP. Trametinib with or without vemurafenib in BRAF mutated non-small cell lung cancer. PLoS One 2015; 10:e0118210. [PMID: 25706985 PMCID: PMC4338247 DOI: 10.1371/journal.pone.0118210] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 01/09/2015] [Indexed: 11/18/2022] Open
Abstract
V-Raf Murine Sarcoma Viral Oncogene Homolog B (BRAF) mutated lung cancer is relatively aggressive and is resistant to currently available therapies. In a recent phase II study for patients with BRAF-V600E non-small cell lung cancer (NSCLC), BRAF V600E inhibitor demonstrated evidence of activity, but 30% of this selected group progressed while on treatment, suggesting a need for developing alternative strategies. We tested two different options to enhance the efficacy of vemurafenib (BRAF V600E inhibitor) in BRAF mutated NSCLC. The first option was the addition of erlotinib to vemurafenib to see whether the combination provided synergy. The second was to induce MEK inhibition (downstream of RAF) with trametinib (MEK inhibitor). We found that the combination of vemurafenib and erlotinib was not synergistic to the inhibition of p-ERK signaling in BRAF-V600E cells. Vemurafenib caused significant apoptosis, G1 arrest and upregulation of BIM in BRAF-V600 cells. Trametinib was effective as a single agent in BRAF mutated cells, either V600E or non-V600E. Finally, the combination of vemurafenib and trametinib caused a small but significant increase in apoptosis as well as a significant upregulation of BIM when compared to either single agent. Thus, hinting at the possibility of utilizing a combinational approach for the management of this group of patients. Importantly, trametinib alone caused upregulation of p-AKT in BRAF non-V600 mutated cells, while this effect was nullified with the combination. This finding suggests that, the combination of a MEK inhibitor with a BRAF inhibitor will be more efficacious in the clinical setting for patients with BRAF mutated NSCLC.
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Affiliation(s)
- Monika Joshi
- Penn State Hershey Cancer Institute, Hershey, Pennsylvania, United States of America
| | - Shawn J. Rice
- Penn State Hershey Cancer Institute, Hershey, Pennsylvania, United States of America
| | - Xin Liu
- Penn State Hershey Cancer Institute, Hershey, Pennsylvania, United States of America
| | - Bruce Miller
- Penn State Hershey Cancer Institute, Hershey, Pennsylvania, United States of America
| | - Chandra P. Belani
- Penn State Hershey Cancer Institute, Hershey, Pennsylvania, United States of America
- * E-mail:
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15
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Qi M, Liu D, Zhang S, Hu P, Sang T. Inhibition of S-phase kinase-associated protein 2-mediated p27 degradation suppresses tumorigenesis and the progression of hepatocellular carcinoma. Mol Med Rep 2015; 11:3934-40. [PMID: 25572801 DOI: 10.3892/mmr.2015.3156] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Accepted: 10/01/2014] [Indexed: 11/06/2022] Open
Abstract
In order to determine the protein expression of S‑phase kinase‑associated protein 2 (Skp2) and p27kip1, and to evaluate their possible prognostic values in malignant liver cancer, tissue samples from 50 patients and 40 controls were assessed and analyzed by immunohistochemistry and western blot analysis. Positive expression of Skp2 was observed in 35 (70.0%) of the hepatocellular carcinoma samples; however, the positive expression of p27kip1 was observed in 6 (15.0%) of the hepatocellular carcinoma samples. The expression of Skp2 was significantly negatively correlated with the expression of p27 (P<0.01). The results from Annexin V‑propidium iodide staining and MTT assays indicated that interference of Skp2 significantly induced apoptosis and inhibited the proliferation of SSMC‑7721 cells. In addition, the levels of endogenous p27 increased in the HepG2 and SSMC‑7721 cells following transfection with siRNA specific to Skp2, suggesting that the Skp2‑mediated degradation of p27kip1 was important in the proliferation of tumor cells. The present study, therefore, provided a molecular reference for the treatment of liver cancer.
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Affiliation(s)
- Ming Qi
- Department of Digestive System, Jinan Central Hospital Affiliated to Shandong University, Jinan, Shandong 250013, P.R. China
| | - Dongmei Liu
- Department of Transfusion Center, Jinan Central Hospital Affiliated to Shandong University, Jinan, Shandong 250013, P.R. China
| | - Shuhong Zhang
- Department of Digestive System, Jinan Central Hospital Affiliated to Shandong University, Jinan, Shandong 250013, P.R. China
| | - Peixin Hu
- Department of Digestive System, Jinan Central Hospital Affiliated to Shandong University, Jinan, Shandong 250013, P.R. China
| | - Tan Sang
- Department of Hematology, Jinan Central Hospital Affiliated to Shandong University, Jinan, Shandong 250013, P.R. China
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16
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Resveratrol and pterostilbene regulate MED28 (magicin/EG1) expression and cell growth in MCF7 human breast cancer cells. J Funct Foods 2015. [DOI: 10.1016/j.jff.2014.11.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
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17
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Abstract
Around 70% of all breast cancers are estrogen receptor alpha positive and hence their development is highly dependent on estradiol. While the invention of endocrine therapies has revolusioned the treatment of the disease, resistance to therapy eventually occurs in a large number of patients. This paper seeks to illustrate and discuss the complexity and heterogeneity of the mechanisms which underlie resistance and the approaches proposed to combat them. It will also focus on the use and development of methods for predicting which patients are likely to develop resistance.
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18
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Turner JG, Dawson J, Cubitt CL, Baz R, Sullivan DM. Inhibition of CRM1-dependent nuclear export sensitizes malignant cells to cytotoxic and targeted agents. Semin Cancer Biol 2014; 27:62-73. [PMID: 24631834 PMCID: PMC4108511 DOI: 10.1016/j.semcancer.2014.03.001] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Revised: 02/25/2014] [Accepted: 03/01/2014] [Indexed: 10/25/2022]
Abstract
Nuclear-cytoplasmic trafficking of proteins is a significant factor in the development of cancer and drug resistance. Subcellular localization of exported proteins linked to cancer development include those involved in cell growth and proliferation, apoptosis, cell cycle regulation, transformation, angiogenesis, cell adhesion, invasion, and metastasis. Here, we examined the basic mechanisms involved in the export of proteins from the nucleus to the cytoplasm. All proteins over 40kDa use the nuclear pore complex to gain entry or exit from the nucleus, with the primary nuclear export molecule involved in these processes being chromosome region maintenance 1 (CRM1, exportin 1 or XPO1). Proteins exported from the nucleus must possess a hydrophobic nuclear export signal (NES) peptide that binds to a hydrophobic groove containing an active-site Cys528 in the CRM1 protein. CRM1 inhibitors function largely by covalent modification of the active site Cys528 and prevent binding to the cargo protein NES. In the absence of a CRM1 inhibitor, CRM1 binds cooperatively to the NES of the cargo protein and RanGTP, forming a trimer that is actively transported out of the nucleus by facilitated diffusion. Nuclear export can be blocked by CRM1 inhibitors, NES peptide inhibitors or by preventing post-translational modification of cargo proteins. Clinical trials using the classic CRM1 inhibitor leptomycin B proved too toxic for patients; however, a new generation of less toxic small molecule inhibitors is being used in clinical trials in patients with both hematological malignancies and solid tumors. Additional trials are being initiated using small-molecule CRM1 inhibitors in combination with chemotherapeutics such as pegylated liposomal doxorubicin. In this review, we present evidence that combining the new CRM1 inhibitors with other classes of therapeutics may prove effective in the treatment of cancer. Potential combinatorial therapies discussed include the use of CRM1 inhibitors and the addition of alkylating agents (melphalan), anthracyclines (doxorubicin and daunomycin), BRAF inhibitors, platinum drugs (cisplatin and oxaliplatin), proteosome inhibitors (bortezomib and carfilzomib), or tyrosine-kinase inhibitors (imatinib). Also, the sequence of treatment may be important for combination therapy. We found that the most effective treatment regimen involved first priming the cancer cells with the CRM1 inhibitor followed by doxorubicin, bortezomib, carfilzomib, or melphalan. This order sensitized both de novo and acquired drug-resistant cancer cell lines.
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Affiliation(s)
- Joel G Turner
- Department of Blood and Marrow Transplantation and Chemical Biology and Molecular Medicine Program, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612, USA
| | - Jana Dawson
- Department of Blood and Marrow Transplantation and Chemical Biology and Molecular Medicine Program, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612, USA
| | - Christopher L Cubitt
- Translational Research Core Laboratory, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612, USA
| | - Rachid Baz
- Department of Malignant Hematology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612, USA
| | - Daniel M Sullivan
- Department of Blood and Marrow Transplantation and Chemical Biology and Molecular Medicine Program, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL 33612, USA.
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19
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Craig ZR, Singh J, Gupta RK, Flaws JA. Co-treatment of mouse antral follicles with 17β-estradiol interferes with mono-2-ethylhexyl phthalate (MEHP)-induced atresia and altered apoptosis gene expression. Reprod Toxicol 2014; 45:45-51. [PMID: 24412242 PMCID: PMC4028413 DOI: 10.1016/j.reprotox.2014.01.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2013] [Revised: 12/02/2013] [Accepted: 01/01/2014] [Indexed: 11/19/2022]
Abstract
Mono-2-ethyhexyl phthalate (MEHP) is a metabolite of a plasticizer found in many consumer products. MEHP inhibits mouse ovarian follicle growth by reducing 17β-estradiol (E2) production. Yet, whether MEHP causes follicle death (atresia) is unclear. We hypothesized that MEHP causes atresia by altering apoptosis gene expression, and that E2 co-treatment blocks these effects. Follicles were exposed to MEHP (0.36-36μM)±E2 for 48-96h to determine the effect of MEHP±E2 on atresia and gene expression. MEHP increased atresia, but this effect was blocked by co-treatment with E2. MEHP increased the expression of the pro-apoptotic gene Aifm1, but decreased that of the pro-apoptotic gene Bok and the anti-apoptotic gene Bcl2l10. E2 interfered with MEHP-induced changes in Aifm1 and Bcl2l10. Our findings suggest that decreased E2 levels are required for MEHP-induced follicle atresia and that Aifm1, Bok, and Bcl2l10 are involved in this process.
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Affiliation(s)
- Zelieann R Craig
- Department of Comparative Biosciences, University of Illinois, 2001 S. Lincoln Avenue, Urbana, IL 61802, United States.
| | - Jeffrey Singh
- Department of Comparative Biosciences, University of Illinois, 2001 S. Lincoln Avenue, Urbana, IL 61802, United States.
| | - Rupesh K Gupta
- Department of Comparative Biosciences, University of Illinois, 2001 S. Lincoln Avenue, Urbana, IL 61802, United States.
| | - Jodi A Flaws
- Department of Comparative Biosciences, University of Illinois, 2001 S. Lincoln Avenue, Urbana, IL 61802, United States.
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20
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Pramod S, Shivakumar K. Mechanisms in cardiac fibroblast growth: an obligate role for Skp2 and FOXO3a in ERK1/2 MAPK-dependent regulation of p27kip1. Am J Physiol Heart Circ Physiol 2014; 306:H844-55. [DOI: 10.1152/ajpheart.00933.2013] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cardiac fibroblast hyperplasia associated with enhanced matrix deposition is a major determinant of tissue remodeling in several disease states of the heart. However, mechanisms controlling cell cycle progression in cardiac fibroblasts remain unexplored. Identification of cell cycle regulatory elements in these cells is important to develop strategies to check adverse cardiac remodeling under pathological conditions. This study sought to probe the mechanisms underlying ERK1/2-mediated p27Kip1 regulation in mitogenically stimulated cardiac fibroblasts. Addition of 10% fetal calf serum to quiescent cultures of adult rat cardiac fibroblasts promoted ERK1/2 activation, as evidenced by its phosphorylation status. Reduction in [3H]thymidine incorporation into DNA increased population doubling time, flow cytometry, and Western blot analysis showing reduced levels of cyclins D and A, p27Kip1 induction, and retinoblastoma protein (Rb) hypophosphorylation in ERK1/2-inhibited cells indicated ERK1/2 dependence of G1-S transition in cardiac fibroblasts. Lack of p27Kip1 protein in serum-stimulated, ERK1/2-active cells was associated with increased levels of Skp2, an E3 ubiquitin ligase for p27Kip1, whose knockdown by RNA interference induced p27Kip1 expression. Further, forced expression of Skp2 in ERK1/2-inhibited cells downregulated p27Kip1. Transcriptional upregulation of p27Kip1 mRNA in ERK1/2-inhibited cells, demonstrated by real-time PCR, correlated with forkhead box O 3a (FOXO3a) transcription factor activation, shown by gel shift assay. FOXO3a knockdown attenuated p27Kip1 mRNA and protein expression in ERK1/2-inhibited cells. We provide evidence for the first time that, in cardiac fibroblasts, activated ERK1/2 regulates p27Kip1 expression transcriptionally and posttranslationally via FOXO3a- and Skp2-dependent mechanisms. Additionally, this study uncovers interesting interactions between critical cell cycle regulatory elements that are only beginning to be understood.
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Affiliation(s)
- S. Pramod
- Division of Cellular and Molecular Cardiology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, India
| | - K. Shivakumar
- Division of Cellular and Molecular Cardiology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Trivandrum, India
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21
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Kim HJ, Cho YR, Kim SH, Seo DW. TIMP-2-derived 18-mer peptide inhibits endothelial cell proliferation and migration through cAMP/PKA-dependent mechanism. Cancer Lett 2013; 343:210-6. [PMID: 24252252 DOI: 10.1016/j.canlet.2013.10.037] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Revised: 10/07/2013] [Accepted: 10/10/2013] [Indexed: 10/26/2022]
Abstract
In the present study, we report the regulatory effects and molecular mechanisms of integrin α3β1-binding tissue inhibitor of metalloproteinases-2 (TIMP-2) 18-mer peptide (peptide 9) on proliferation, migration and tubular formation in human umbilical vein endothelial cells. Peptide 9 markedly inhibits vascular endothelial growth factor-A-stimulated cell proliferation. This anti-proliferative activity of peptide 9 is mediated by cAMP/protein kinase A (PKA)-dependent induction of p27(Kip1) expression as evidenced by using adenylate cyclase inhibitor SQ22536 or PKA inhibitor H89. Peptide 9-mediated inhibition of endothelial cell migration and tubular formation is also dependent on cAMP/PKA activity. Collectively, our findings clearly show the pharmacological roles and action mechanism of peptide 9 in regulating angiogenic responses through cAMP/PKA activity, and support further development as a potential therapeutics for the treatment of angiogenesis-related disorders including cancer.
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Affiliation(s)
- Hyeon-Ju Kim
- Department of Pharmacy, College of Pharmacy, Dankook University, Cheonan 330-714, Republic of Korea
| | - Young-Rak Cho
- Department of Pharmacy, College of Pharmacy, Dankook University, Cheonan 330-714, Republic of Korea
| | - Soo Hyeon Kim
- Department of Molecular Bioscience, College of Biomedical Science, Kangwon National University, Chuncheon 200-701, Republic of Korea
| | - Dong-Wan Seo
- Department of Pharmacy, College of Pharmacy, Dankook University, Cheonan 330-714, Republic of Korea.
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22
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Li A, Zou F, Fu H, Cui G, Yan Y, Wu Q, Gu X. Upregulation of CRM1 relates to neuronal apoptosis after traumatic brain injury in adult rats. J Mol Neurosci 2013; 51:208-18. [PMID: 23494640 DOI: 10.1007/s12031-013-9994-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Accepted: 03/04/2013] [Indexed: 12/11/2022]
Abstract
Traumatic brain injury (TBI) initiates a complex series of neurochemical and signaling changes that leads to neuronal dysfunction and over-reactive astrocytes. There is increasing evidence that CRM1 mediated P27(Kip1), which is a potent inhibitor of G1 cyclin-dependent kinases complexes, nuclear export-dependent or -independent Jab1/CSN5, and cytoplasmic degradation in cells. Up to now, the function of CRM1 in central nervous system (CNS) is still with limited acquaintance. In our study, to investigate whether CRM1 is involved in CNS lesion, we performed a TBI model in adult rats. Western blot and RT-PCR analysis revealed that the level of protein and mRNA of CRM1 increased in ipsilateral brain cortex in comparison to the contralateral. Immunohistochemistry and immunofluorescence double labeling indicated that CRM1 was shutting into nucleus around the wound, and increased CRM1 co-localized with P27(Kip1). Terminal deoxynucleotidyl transferase deoxy-UTP-nick end labeling (TUNEL) staining suggested that CRM1 was involved in neuronal apoptosis after brain injury. We also investigated co-localization of CRM1 and active-caspase-3 in the ipsilateral brain cortex. In addition, the expression patterns of Bax and active-caspase-3 were parallel with that of CRM1. Based on our data, we suggested that CRM1 might play an important role in neuronal apoptosis following TBI, and might provide a basis for the further study on its role in regulating the expression of P27(Kip1) and cell cycle re-entry in TBI.
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Affiliation(s)
- Aihong Li
- Department of Neurology, Affiliated Hospital of Nantong University, Nantong, Jiangsu, 226001, People's Republic of China
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23
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Zhang W, Tan W, Wu X, Poustovoitov M, Strasner A, Li W, Borcherding N, Ghassemian M, Karin M. A NIK-IKKα module expands ErbB2-induced tumor-initiating cells by stimulating nuclear export of p27/Kip1. Cancer Cell 2013; 23:647-59. [PMID: 23602409 PMCID: PMC3981467 DOI: 10.1016/j.ccr.2013.03.012] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2012] [Revised: 10/30/2012] [Accepted: 03/15/2013] [Indexed: 12/20/2022]
Abstract
IκB kinase α (IKKα) activity is required for ErbB2-induced mammary tumorigenesis. Here, we show that IKKα and its activator, NF-κB-inducing kinase (NIK), support the expansion of tumor-initiating cells (TICs) that copurify with a CD24(med)CD49f(hi) population from premalignant ErbB2-expressing mammary glands. Upon activation, IKKα enters the nucleus, phosphorylates the cyclin-dependent kinase (CDK) inhibitor p27/Kip1, and stimulates its nuclear export or exclusion. Reduced p27 expression rescues mammary tumorigenesis in mice deficient in IKKα kinase activity and restores TIC self-renewal. IKKα is also likely to be involved in human breast cancer, where its expression shows an inverse correlation with metastasis-free survival, and its presence in the nucleus of invasive ductal carcinomas (IDCs) is associated with decreased nuclear p27 abundance.
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Affiliation(s)
- Weizhou Zhang
- Department of Pharmacology, Laboratory of Gene Regulation and Signal Transduction, School of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0723, USA
- Department of Pathology, Laboratory of Gene Regulation and Signal Transduction, School of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0723, USA
- Department of Pathology, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Wei Tan
- Department of Pharmacology, Laboratory of Gene Regulation and Signal Transduction, School of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0723, USA
- Department of Pathology, Laboratory of Gene Regulation and Signal Transduction, School of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0723, USA
| | - Xuefeng Wu
- Department of Pharmacology, Laboratory of Gene Regulation and Signal Transduction, School of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0723, USA
- Department of Pathology, Laboratory of Gene Regulation and Signal Transduction, School of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0723, USA
| | - Maxim Poustovoitov
- Department of Pharmacology, Laboratory of Gene Regulation and Signal Transduction, School of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0723, USA
- Department of Pathology, Laboratory of Gene Regulation and Signal Transduction, School of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0723, USA
| | - Amy Strasner
- Department of Pharmacology, Laboratory of Gene Regulation and Signal Transduction, School of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0723, USA
- Department of Pathology, Laboratory of Gene Regulation and Signal Transduction, School of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0723, USA
| | - Wei Li
- Department of Pharmacology, Laboratory of Gene Regulation and Signal Transduction, School of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0723, USA
- Department of Pathology, Laboratory of Gene Regulation and Signal Transduction, School of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0723, USA
| | - Nicholas Borcherding
- Department of Pathology, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Majid Ghassemian
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0723, USA
| | - Michael Karin
- Department of Pharmacology, Laboratory of Gene Regulation and Signal Transduction, School of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0723, USA
- Department of Pathology, Laboratory of Gene Regulation and Signal Transduction, School of Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0723, USA
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24
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Foster JS, Fish LM, Phipps JE, Bruker CT, Lewis JM, Bell JL, Solomon A, Kestler DP. Odontogenic ameloblast-associated protein (ODAM) inhibits growth and migration of human melanoma cells and elicits PTEN elevation and inactivation of PI3K/AKT signaling. BMC Cancer 2013; 13:227. [PMID: 23648148 PMCID: PMC3651709 DOI: 10.1186/1471-2407-13-227] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Accepted: 04/25/2013] [Indexed: 12/17/2022] Open
Abstract
Background The Odontogenic Ameloblast-associated Protein (ODAM) is expressed in a wide range of normal epithelial, and neoplastic tissues, and we have posited that ODAM serves as a novel prognostic biomarker for breast cancer and melanoma. Transfection of ODAM into breast cancer cells yields suppression of cellular growth, motility, and in vivo tumorigenicity. Herein we have extended these studies to the effects of ODAM on cultured melanoma cell lines. Methods The A375 and C8161 melanoma cell lines were stably transfected with ODAM and assayed for properties associated with tumorigenicity including cell growth, motility, and extracellular matrix adhesion. In addition, ODAM–transfected cells were assayed for signal transduction via AKT which promotes cell proliferation and survival in many neoplasms. Results ODAM expression in A375 and C8161 cells strongly inhibited cell growth and motility in vitro, increased cell adhesion to extracellular matrix, and yielded significant cytoskeletal/morphologic rearrangement. Furthermore, AKT activity was downregulated by ODAM expression while an increase was noted in expression of the PTEN (phosphatase and tensin homolog on chromosome 10) tumor suppressor gene, an antagonist of AKT activation. Increased PTEN in ODAM-expressing cells was associated with increases in PTEN mRNA levels and de novo protein synthesis. Silencing of PTEN expression yielded recovery of AKT activity in ODAM-expressing melanoma cells. Similar PTEN elevation and inhibition of AKT by ODAM was observed in MDA-MB-231 breast cancer cells while ODAM expression had no effect in PTEN-deficient BT-549 breast cancer cells. Conclusions The apparent anti-neoplastic effects of ODAM in cultured melanoma and breast cancer cells are associated with increased PTEN expression, and suppression of AKT activity. This association should serve to clarify the clinical import of ODAM expression and any role it may serve as an indicator of tumor behavior.
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Affiliation(s)
- James S Foster
- Department of Medicine, Human Immunology and Cancer Program, University of Tennessee Health Sciences Center-Knoxville, Knoxville, TN 37920, USA
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25
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Gao X, Yu L, Castro L, Tucker CJ, Moore AB, Xiao H, Dixon D. An essential role of p27 downregulation in fenvalerate-induced cell growth in human uterine leiomyoma and smooth muscle cells. Am J Physiol Endocrinol Metab 2012; 303:E1025-35. [PMID: 22850687 PMCID: PMC3469610 DOI: 10.1152/ajpendo.00107.2012] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Previously, we reported that fenvalerate (Fen) promotes proliferation of human uterine leiomyoma (UtLM) cells by enhancing progression of cells from G(0)-G(1) to S phase through molecular mechanisms independent of estrogen receptor-α and -β. The cyclin-dependent kinase (CDK) inhibitor p27, which blocks G(1) to S phase transitions and is an important regulator of CDK2, is often decreased in hormonally regulated diseases, including uterine leiomyomas. Therefore, we were interested in whether Fen could regulate the expression of p27 and whether p27 might play a role in Fen-induced cell proliferation. Expression of p27 in Fen-treated UtLM and uterine smooth muscle cells (UtSMCs) was examined. We found that p27 mRNA was significantly downregulated and that protein levels were decreased in both cell types treated with 10 μM Fen for 24 h compared with respective controls. Overexpression of p27 in UtLM cells and UtSMCs using an adenovirus doxycycline (Dox)-regulated Tet-off system abrogated the proliferative effects of Fen, as evidenced by decreased total cell numbers and BrdU incorporation. Fen treatment increased CDK2 mRNA expression levels; however, overexpression of p27 also abolished this effect. In contrast, Dox treatment dramatically restored the above muted responses. Finally, we utilized siRNA to knock down p27 expression. After transfection, mRNA levels of p27 were downregulated in UtLM cells and UtSMCs and total cell numbers and BrdU incorporation increased significantly compared with nontransfected cells. Fen treatment in the presence of p27 silencing enhanced the increased cell counts and BrdU labeling in UtLM cells and UtSMCs. Taken together, these results indicate that p27 downregulation is critical for Fen-induced cell proliferation.
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Affiliation(s)
- Xiaohua Gao
- Molecular Pathogenesis Group, National Toxicology Program (NTP) Laboratory Branch, NTP, National Institute ofEnvironmental Health Sciences, National Institutes of Health (NIH), Department of Health and Human Services (DHHS), Research Triangle Park, North Carolina 27709, USA
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26
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Jeon MJ, Yang W, Seo HS, Wang ES, Shin I. Down-regulation of estrogen receptor α (ERα) transcriptional activity by p27 is mediated by inhibition of ERα nuclear localization and modulation of the ERα transcriptional complex. Cell Signal 2012; 24:2249-58. [PMID: 22820506 DOI: 10.1016/j.cellsig.2012.07.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2012] [Revised: 06/25/2012] [Accepted: 07/14/2012] [Indexed: 01/22/2023]
Abstract
To investigate the role of p27 on estrogen receptor (ER)α-mediated transcription, we generated MCF-7 cells with knocked down p27 via retroviral delivery of p27 shRNA. Suppression of p27 expression in MCF-7 cells resulted in up-regulation of ERα-mediated transcription by estradiol compared to the levels in control MCF-7 cells. Accordingly, transient transfection studies in 293T cells revealed that overexpression of p27 reduced ERα-mediated transcription. The effect of p27 on ERα transcriptional activity was independent of cell cycle arrest by p27, as cell cycle arrest induced by serum starvation did not significantly affect ERα-mediated transcription. Further, we observed that p27 inhibited nuclear localization of ERα, and that p27 was associated with ERα in the cytoplasm. We also investigated the role of p27 in the modulation of ERα transcriptional activity in the nucleus. We found that p27 negatively modulated ERα transcriptional activity by inhibiting association of cyclin D1 with ERα and recruiting BRCA1 to ERα transcriptional complex. Taken together, these data suggest that p27 inhibits ERα transcriptional activity by two independent mechanisms, namely, physical nuclear exclusion of ERα, and modulation of the ERα transcriptional complex.
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Affiliation(s)
- Min Jeong Jeon
- Department of Life Science, College of Natural Sciences, Hanyang University, Seoul 133-791, Republic of Korea
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27
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He W, Wang X, Chen L, Guan X. A crosstalk imbalance between p27(Kip1) and its interacting molecules enhances breast carcinogenesis. Cancer Biother Radiopharm 2012; 27:399-402. [PMID: 22690887 DOI: 10.1089/cbr.2010.0802] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
p27(Kip1) (p27) is an inhibitor of cyclin/cyclin-dependent kinase complexes, the nuclear loss of which indicates poor prognoses in various solid tumors. In breast cancer cells, the p27 expression level usually decreases during tumor development and progression. In addition, p27 cytoplasmic mislocalization has been reported, but the exact molecular mechanisms remain unclear. Studies have indicated that its phosphorylation status is the key regulator and that several signal transduction pathways are involved in the regulation of both the expression and distribution of p27. To further understand the signals involved, the differences in the profiles of interacting proteins between tumor and normal cells should be elucidated. It is well known that p27 has various interacting partners, such as cyclin, cyclin-depend kinases, CRM1, Jab1, SKP2, and Spy1. Assays used to profile these proteins show differing intracellular p27 expression and localization depending on the cell-cycle phase. We hypothesize that the imbalance of crosstalk between p27 and the other molecules involved in the same signaling pathways plays an indispensable role in breast cancer carcinogenesis.
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Affiliation(s)
- Weiwei He
- Department of Oncology, Jinling Hospital, School of Medicine, Nanjing University, China
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28
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Jäkel H, Peschel I, Kunze C, Weinl C, Hengst L. Regulation of p27 (Kip1) by mitogen-induced tyrosine phosphorylation. Cell Cycle 2012; 11:1910-7. [PMID: 22580455 DOI: 10.4161/cc.19957] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Extracellular mitogen signal transduction is initiated by ligand binding to specific receptors of target cells. This causes a cellular response that frequently triggers the activation of tyrosine kinases. Non-receptor kinases like Src and Lyn can directly phosphorylate the Cdk inhibitor protein p27 (Kip1) . Tyrosine phosphorylation can cause impaired Cdk-inhibitory activity and decreased stability of p27. In addition to these non-receptor tyrosine kinases, the receptor-associated tyrosine kinase Janus kinase 2 (JAK2) was recently identified to phosphorylate p27. JAK2 becomes activated through binding of various cytokines and growth factors to their corresponding receptors and can directly bind and selectively phosphorylate tyrosine residue 88 (Y88) of the Cdk inhibitor p27. This impairs Cdk inhibition by p27 and promotes its ubiquitin-dependent proteasomal degradation. Via this mechanism, JAK2 can link cytokine and growth factor initiated signal transduction to p27 regulation, whereas oncogenes like JAK2V617F or BCR-Abl can use this mechanism to inactivate the Cdk inhibitor.
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Affiliation(s)
- Heidelinde Jäkel
- Division of Medical Biochemistry; Biocenter; Innsbruck Medical University; Innsbruck, Austria
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29
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Turner JG, Dawson J, Sullivan DM. Nuclear export of proteins and drug resistance in cancer. Biochem Pharmacol 2012; 83:1021-32. [PMID: 22209898 PMCID: PMC4521586 DOI: 10.1016/j.bcp.2011.12.016] [Citation(s) in RCA: 278] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Revised: 12/09/2011] [Accepted: 12/12/2011] [Indexed: 12/14/2022]
Abstract
The intracellular location of a protein is crucial to its normal functioning in a cell. Cancer cells utilize the normal processes of nuclear-cytoplasmic transport through the nuclear pore complex of a cell to effectively evade anti-neoplastic mechanisms. CRM1-mediated export is increased in various cancers. Proteins that are exported in cancer include tumor-suppressive proteins such as retinoblastoma, APC, p53, BRAC1, FOXO proteins, INI1/hSNF5, galectin-3, Bok, nucleophosmin, RASSF2, Merlin, p21(CIP), p27(KIP1), N-WASP/FAK, estradiol receptor and Tob, drug targets topoisomerase I and IIα and BCR-ABL, and the molecular chaperone protein Hsp90. Here, we review in detail the current processes and known structures involved in the export of a protein through the nuclear pore complex. We also discuss the export receptor molecule CRM1 and its binding to the leucine-rich nuclear export signal of the cargo protein and the formation of a nuclear export trimer with RanGTP. The therapeutic potential of various CRM1 inhibitors will be addressed, including leptomycin B, ratjadone, KOS-2464, and specific small molecule inhibitors of CRM1, N-azolylacrylate analogs, FOXO export inhibitors, valtrate, acetoxychavicol acetate, CBS9106, and SINE inhibitors. We will also discuss examples of how drug resistance may be reversed by targeting the exported proteins topoisomerase IIα, BCR-ABL, and galectin-3. As effective and less toxic CRM1 export inhibitors become available, they may be used as both single agents and in combination with current chemotherapeutic drugs. We believe that the future development of low-toxicity, small-molecule CRM1 inhibitors may provide a new approach to treating cancer.
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Affiliation(s)
- Joel G. Turner
- Blood and Marrow Transplant Department and Experimental Therapeutics Program, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL 33612, USA
| | - Jana Dawson
- Blood and Marrow Transplant Department and Experimental Therapeutics Program, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL 33612, USA
| | - Daniel M. Sullivan
- Blood and Marrow Transplant Department and Experimental Therapeutics Program, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL 33612, USA
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30
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Wang Z, Fukushima H, Inuzuka H, Wan L, Liu P, Gao D, Sarkar FH, Wei W. Skp2 is a promising therapeutic target in breast cancer. Front Oncol 2012; 1. [PMID: 22279619 PMCID: PMC3263529 DOI: 10.3389/fonc.2011.00057] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Breast cancer is the most common type of cancer among American women, and remains the second leading cause of cancer-related death for female in the United States. It has been known that several signaling pathways and various factors play critical roles in the development and progression of breast cancer, such as estrogen receptor, Notch, PTEN, human epidermal growth factor receptor 2, PI3K/Akt, BRCA1, and BRCA2. Emerging evidence has shown that the F-box protein S-phase kinase associated protein 2 (Skp2) also plays an important role in the pathogenesis of breast cancer. Therefore, in this brief review, we summarize the novel functions of Skp2 in the pathogenesis of breast cancer. Moreover, we provide further evidence regarding the state of our knowledge toward the development of novel Skp2 inhibitors especially natural "chemopreventive agents" as targeted approach for the prevention and/or treatment of breast cancer.
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Affiliation(s)
- Zhiwei Wang
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
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31
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Tyson JJ, Baumann WT, Chen C, Verdugo A, Tavassoly I, Wang Y, Weiner LM, Clarke R. Dynamic modelling of oestrogen signalling and cell fate in breast cancer cells. Nat Rev Cancer 2011; 11:523-32. [PMID: 21677677 PMCID: PMC3294292 DOI: 10.1038/nrc3081] [Citation(s) in RCA: 135] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cancers of the breast and other tissues arise from aberrant decision-making by cells regarding their survival or death, proliferation or quiescence, damage repair or bypass. These decisions are made by molecular signalling networks that process information from outside and from within the breast cancer cell and initiate responses that determine the cell's survival and reproduction. Because the molecular logic of these circuits is difficult to comprehend by intuitive reasoning alone, we present some preliminary mathematical models of the basic decision circuits in breast cancer cells that may aid our understanding of their susceptibility or resistance to endocrine therapy.
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Affiliation(s)
- John J Tyson
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA.
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32
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Rodriguez BAT, Weng YI, Liu TM, Zuo T, Hsu PY, Lin CH, Cheng AL, Cui H, Yan PS, Huang THM. Estrogen-mediated epigenetic repression of the imprinted gene cyclin-dependent kinase inhibitor 1C in breast cancer cells. Carcinogenesis 2011; 32:812-21. [PMID: 21304052 DOI: 10.1093/carcin/bgr017] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
While tumor suppressor genes frequently undergo epigenetic silencing in cancer, how the instructions directing this transcriptional repression are transmitted in cancer cells remain largely unclear. Expression of cyclin-dependent kinase inhibitor 1C (CDKN1C), an imprinted gene on chromosomal band 11 p15.5, is reduced or lost in the majority of breast cancers. Here, we report that CDKN1C is suppressed by estrogen through epigenetic mechanisms involving the chromatin-interacting noncoding RNA KCNQ1OT1 and CCCTC-binding factor (CTCF). Activation of estrogen signaling reduced CDKN1C expression 3-fold (P < 0.001) and established repressive histone modifications at the 5' regulatory region of the locus. These events were concomitant with induction of KCNQ1OT1 expression as well as increased recruitment of CTCF to both the distal KCNQ1OT1 promoter-associated imprinting control region (ICR) and the CDKN1C locus. Transient depletion of CTCF by small interfering RNA increased CDKN1C expression and significantly reduced the estrogen-mediated repression of CDKN1C. Further studies in breast cancer cell lines indicated that the epigenetic silencing of CDKN1C occurs in part as the result of genetic loss of the inactive methylated 11p15.5 ICR allele (R(2) = 0.612, P < 0.001). We also found a novel cis-encoded antisense transcript, CDKN1C-AS, which is induced by estrogen signaling following pharmacologic inhibition of DNA methyltransferase and histone deacetylase activity. Forced expression of CDKN1C-AS was capable of repressing endogenous CDKN1C in vivo. Our findings suggest that in addition to promoter hypermethylation, epigenetic repression of tumor suppressor genes by CTCF and noncoding RNA transcripts could be more common and important than previously understood.
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Affiliation(s)
- Benjamin A T Rodriguez
- Human Cancer Genetics Program, Department of Molecular Virology, Immunology, and Medical Genetics, The Ohio State University, Columbus, OH 43210, USA
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33
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Zheng H, Li S, Wu Z, Zhang Y, Hu S, Yan Y, Li Y. Differential response of multiple zebrafish hepatic F-box protein genes to 17alpha-ethinylestradiol treatment. J Environ Sci (China) 2011; 23:664-670. [PMID: 21793410 DOI: 10.1016/s1001-0742(10)60578-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Estrogens are accumulating in environment and their effects on a variety of reproductive processes and tumorigenesis were reported by previous study, but the mechanism of estrogen promoting neoplasia was still not clear. F-box protein (FBP) is the component of E3 ubiquitin ligase which takes part in a variety of key biological processes. In this study, using mature male zebrafish, which are more sensitive to estrogen treatment, we examined influence of 17alpha-ethinylestradiol (EE2) exposure on the expression of a series of hepatic FBP genes, which take part in a variety of biological processes, including tumorigenesis. The influence of EE2 on the expression of hepatic mRNA concentrations of FBP genes were quantified based on the expression of the optimal internal control gene in male zebrafish after 7-day exposure to EE2, from a low-dose concentration (1 ng/L) to environmentally relevant concentrations (10, 100 ng/L). Our results showed that EE2 exposure reduced the expression of fbxl14a, fbxl14b, fbxo25 and beta-TRCP2b, but enchanced the expression of skp2. While the alterations in fbxl2, fbxw7, fbxo9, beta-TRCP2a, fbxl18 and fbxo45 mRNA levels were not observed after EE2 exposure. Thus, our results showed that the expression of hepatic FBP genes exhibited differentially in male zebrafish exposed EE2. The changes of the expression level of FBP genes induced by EE2 may be an important clue to elucidate the correlations of estrogen and hepatic tumors.
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Affiliation(s)
- Hongping Zheng
- Shanghai Key Laboratory for MolecularAndrology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
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34
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Hershko DD. Cyclin-dependent kinase inhibitor p27 as a prognostic biomarker and potential cancer therapeutic target. Future Oncol 2010; 6:1837-47. [PMID: 21142858 DOI: 10.2217/fon.10.144] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The prognosis and clinical management of patients with cancer is commonly determined by traditional clinical and pathological factors. Nevertheless, patients may present with significantly different clinical outcomes despite similar clinicopathological features. This has prompted intense research to find biological markers that may closely reflect tumor biology and thereby clinical outcome. This article presents the current knowledge on the prognostic significance of p27 expression in cancer and its potential role as a target for future therapy.
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Affiliation(s)
- Dan D Hershko
- Department of Surgery & Breast Health Institute, Rambam Health Care Campus & the Technion – Israel Institute of Technology, Haifa 31096, Israel
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35
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Cross-talk between PI3K and estrogen in the mouse thyroid predisposes to the development of follicular carcinomas with a higher incidence in females. Oncogene 2010; 29:5678-86. [PMID: 20676139 PMCID: PMC2967724 DOI: 10.1038/onc.2010.308] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
It is well known that thyroid disease is more frequent in women than in men, however the molecular basis for this gender difference is still poorly understood. PI3K activation, through different mechanisms including loss of the PTEN tumor suppressor, is being increasingly recognized as a major player in the development of thyroid neoplastic lesions. Loss of Pten in the mouse thyroid results in a significant increase in the thyrocyte proliferative index, which is more prominent in the female mice. Here we show that 52% of the Pten−/− female mice, but only 12% of the males, develop follicular adenomas by one year of age. In addition, 50% of female mutants, but only 35% of males older than one year of age develop invasive, and often metastatic, follicular carcinomas. Mutant females have a significantly shorter overall survival compared to male mutants. Hormonal manipulation experiments established a direct role of estrogens in controlling the increased thyrocyte proliferation index in mutant females. Furthermore, while genetic ablation of one Cdkn1b allele accelerated the development of neoplastic lesions, it also abolished the gender differences in survival and reduced the difference in neoplastic lesion development rate, underlining a key role of p27 in mediating estrogen action in the thyroid follicular cells. These data, based on a clinically relevant model of thyroid follicular carcinoma, provide for the first time in vivo evidence that circulating estrogens are directly responsible for the increased female susceptibility to thyroid disease, at least upon activation of the PI3K pathway, and provide novel insights into the gender differences characterizing thyroid neoplastic disorders.
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36
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Lu Z, Hunter T. Ubiquitylation and proteasomal degradation of the p21(Cip1), p27(Kip1) and p57(Kip2) CDK inhibitors. Cell Cycle 2010; 9:2342-52. [PMID: 20519948 DOI: 10.4161/cc.9.12.11988] [Citation(s) in RCA: 174] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The expression levels of the p21(Cip1) family CDK inhibitors (CKIs), p21(Cip1), p27(Kip1) and p57(Kip2), play a pivotal role in the precise regulation of cyclin-dependent kinase (CDK) activity, which is instrumental to proper cell cycle progression. The stabilities of p21(Cip1), p27(Kip1) and p57(Kip2) are all tightly and differentially regulated by ubiquitylation and proteasome-mediated degradation during various stages of the cell cycle, either in steady state or in response to extracellular stimuli, which often elicit site-specific phosphorylation of CKIs triggering their degradation.
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Affiliation(s)
- Zhimin Lu
- Brain Tumor Center and Department of Neuro-Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX, USA.
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37
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Abstract
This paper reviews the current understanding of the vitamin D-induced differentiation of neoplastic cells, which results in the generation of cells that acquire near-normal, mature phenotype. Examples of the criteria by which differentiation is recognized in each cell type are provided, and only those effects of 1alpha,25-dihydroxyvitamin D(3) (1,25D) on cell proliferation and survival that are associated with the differentiation process are emphasized. The existing knowledge, often fragmentary, of the signaling pathways that lead to vitamin D-induced differentiation of colon, breast, prostate, squamous cell carcinoma, osteosarcoma, and myeloid leukemia cancer cells is outlined. The important distinctions between the different mechanisms of 1,25D-induced differentiation that are cell-type and cell-context specific are pointed out where known. There is a considerable body of evidence that the principal human cancer cells can be suitable candidates for chemoprevention or differentiation therapy with vitamin D. However, further studies are needed to fully understand the underlying mechanisms in order to improve the therapeutic approaches.
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Affiliation(s)
- Elzbieta Gocek
- Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland
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38
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Glover CE, Gurley KE, Kim KH, Storer B, Fero ML, Kemp CJ. Endocrine dysfunction in p27Kip1 deficient mice and susceptibility to Wnt-1 driven breast cancer. Carcinogenesis 2009; 30:1058-63. [PMID: 19380520 DOI: 10.1093/carcin/bgp089] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The cyclin-dependent kinase (Cdk) inhibitor p27(Kip1) (p27) is a marker of prognosis in many cancers, including breast cancer. Low p27 expression correlates with poor prognosis, especially in hormone receptor positive breast tumors. This association suggests a role for p27 in hormone-dependent cancer. We used the Wnt-1 transgenic mouse model to further explore the role of p27 in hormone-driven breast cancer. We found that p27 deficiency did not alter breast cancer rate in either male or female Wnt-1 mice. However, we did find p27-/- females had reduced levels of serum progesterone (P) and increased variability in estradiol (E), which could have affected their cancer susceptibility. To equalize hormone levels, an additional cohort of Wnt-1 female mice was ovariectomized and implanted with slow release pellets of E and P. Although this treatment did not alter the breast cancer rate, it did accelerate the development of pituitary and gastric tumors in p27-/- mice. This study shows that while not a significant inhibitor of Wnt-1-driven breast cancer, p27 inhibits gastric tumors, whose latency is modulated by sex steroids.
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Karpuzoglu E, Phillips RA, Dai R, Graniello C, Gogal RM, Ahmed SA. Signal transducer and activation of transcription (STAT) 4beta, a shorter isoform of interleukin-12-induced STAT4, is preferentially activated by estrogen. Endocrinology 2009; 150:1310-20. [PMID: 18988675 PMCID: PMC2654738 DOI: 10.1210/en.2008-0832] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Estrogen, a natural immunomodulatory compound, has been shown to promote the induction of a prototype T helper 1 cytokine, interferon (IFN)-gamma, as well as to up-regulate IFNgamma-mediated proinflammatory molecules (nitric oxide, cyclooxygenase 2, monocyte chemoattractant protein 1). Because IL-12 is a major IFNgamma-inducing cytokine, in this study we investigated whether estrogen treatment of wild-type C57BL/6 mice alters IL-12-mediated signaling pathways. A recent study has shown that IL-12 activates two isoforms of signal transducer and activation of transcription (STAT) 4, a normal-sized (full-length STAT4alpha) and a truncated form (STAT4beta). Interestingly, we found that estrogen treatment preferentially up-regulates the phosphorylation of STAT4beta in splenic lymphoid cells. Time kinetic data showed the differential activation of STAT4beta in splenic lymphoid cells from estrogen-treated mice, but not in cells from placebo controls. The activation of STAT4beta was mediated by IL-12 and not IFNgamma because deliberate addition or neutralization of IL-12, but not IFNgamma, affected the activation of STAT4beta. In contrast to IL-12-induced activation of STAT4beta in cells from estrogen-treated mice, STAT4alpha was not increased, rather it tended to be decreased. In this context, STAT4alpha-induced p27(kip1) protein was decreased in concanavalin A + IL-12-activated lymphocytes from estrogen-treated mice only. By using the in vitro DNA binding assay, we confirmed the ability of pSTAT4beta to bind to the IFNgamma-activated sites (IFNgamma activation sequences)/STAT4-binding sites in estrogen-treated mice. Our data are the first to show that estrogen apparently has selective effects on IL-12-mediated signaling by preferentially activating STAT4beta. These novel findings are likely to provide new knowledge with regard to estrogen regulation of inflammation.
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Affiliation(s)
- Ebru Karpuzoglu
- Department of Biomedical Sciences, Center for Molecular Medicine and Infectious Diseases, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Tech, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, USA
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40
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Malone JL, Nelson AC, Lieberman R, Anderson S, Holt JT. Oestrogen-mediated phosphorylation and stabilization of BRCA2 protein in breast. J Pathol 2009; 217:380-8. [PMID: 19016568 DOI: 10.1002/path.2458] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Disease-associated BRCA2 mutations typically result in protein truncations that delete the phosphorylation-regulated S3291 BRCA2 domain that interacts with Rad51. BRCA2 hereditary breast cancers are usually ER(+), differing from BRCA1 hereditary cancers, which are usually ER(-). We studied BRCA2 protein expression and S3291 phosphorylation in normal breast tissues and in sporadic breast cancers and observed that BRCA2 is expressed and phosphorylated in normal breast and 10 ER(+) breast cancers but not in 10 ER(-) breast cancers. In order to study this correlation between ER and BRCA2 expression, we studied ER(+) breast cancer cell lines. We found that a rapid increase in BRCA2 S3291 phosphorylation occurs following 17-beta-oestradiol (E2) treatment. This increase seen in BRCA2 total and phospho-S3291 protein levels was found to be unaffected with cycloheximide pre-treatment, but decreased following tamoxifen, ICI 182,780 or roscovitine treatment. This suggests a requirement for ER and cdk (cyclin-dependent kinase) in mediating the increased protein levels. MCF7 cell cycle distribution analysis following E2, in both the presence and absence of roscovitine (a cdk inhibitor), did not demonstrate any changes during an 8 h period, which further supports our hypothesis that mitogenic effects of E2 are not predominant at early time points. Studies with MG132 proteasome inhibitor and siRNA to skp2 support a model in which skp2-mediated proteasomal degradation of BRCA2 rapidly degrades BRCA2 protein in the absence of hormone treatment, which likely inhibits this pathway. E2 was shown to improve survival of MCF7 cells upon radiation treatment and roscovitine partially reversed this effect. We have demonstrated that BRCA2 protein is specifically expressed in ER(+) breast cancers and are investigating a pathway that may show a link between E2 action and BRCA2 protein function in breast cancer.
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Affiliation(s)
- J L Malone
- Department of Pathology, University of Colorado at Denver (UCDHSC), Aurora, CO 80045, USA
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Wang H, Song X, Logsdon C, Zhou G, Evans DB, Abbruzzese JL, Hamilton SR, Tan TH, Wang H. Proteasome-mediated degradation and functions of hematopoietic progenitor kinase 1 in pancreatic cancer. Cancer Res 2009; 69:1063-70. [PMID: 19141650 DOI: 10.1158/0008-5472.can-08-1751] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Hematopoietic progenitor kinase 1 (HPK1) regulates stress responses, proliferation, and apoptosis in hematopoietic cells. In this study, we examined the expression, regulation, and functions of HPK1 in pancreatic ductal adenocarcinomas (PDA). We found that loss of HPK1 protein expression correlated significantly with the progression of pancreatic intraepithelial neoplasias (P = 0.001) and development of invasive PDA. Similarly, HPK1 protein was not expressed in any of eight PDA cell lines examined but was expressed in immortalized human pancreatic duct epithelial (HPDE) cells. There was no difference in HPK1 mRNA levels in PDA cell lines or primary PDA compared with those in HPDE cells or ductal epithelium in chronic pancreatitis and normal pancreas, respectively. Treatment of Panc-1 cells with a proteasome inhibitor, MG132, increased the HPK1 protein levels in a dose-dependent manner, suggesting that alteration in proteasome activity contributes to the loss of HPK1 protein expression in pancreatic cancer. Like the endogenous HPK1, both wild-type HPK1 and its kinase-dead mutant, HPK1-M46, overexpressed in Panc-1 cells, were also targeted by proteasome-mediated degradation. After MG132 withdrawal, wild-type HPK1 protein expression was markedly decreased within 24 hours, but kinase-dead HPK1 mutant protein expression was sustained for up to 96 hours. Therefore, HPK1 kinase activities were required for the loss of HPK1 protein in PDAs. Furthermore, restoring wild-type HPK1 protein in PDA cells led to the increase in p21 and p27 protein expression and cell cycle arrest. Thus, HPK1 may function as a novel tumor suppressor and its loss plays a critical role in pancreatic cancer.
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Affiliation(s)
- Hua Wang
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer, Baylor College of Medicine, Houston, Texas 77030, USA
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Huang HC, Way TD, Lin CL, Lin JK. EGCG stabilizes p27kip1 in E2-stimulated MCF-7 cells through down-regulation of the Skp2 protein. Endocrinology 2008; 149:5972-83. [PMID: 18719023 DOI: 10.1210/en.2008-0408] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Loss of p27Kip1 is associated with a poor prognosis in breast cancer. According to previous findings, a decrease in p27Kip1 levels is mainly the result of enhanced proteasome-dependent degradation mediated by its specific ubiquitin ligase subunit S-phase kinase protein 2 (Skp2). Epigallocatechin-3-gallate (EGCG), the main constituent of green tea, was found to stabilize p27Kip1 levels in breast cancer, but whether this effect is mediated through changes in Skp2 expression remains unclear. Here we investigated the mechanisms involved in EGCG's growth inhibition of estrogen-responsive human breast cancer MCF-7 cells. In our results, EGCG increased p27Kip1 and decreased Skp2 in a time- and dose-dependent manner, suggesting that p27Kip1 and Skp2 may be involved in the growth inhibition by EGCG in estrogen-stimulated MCF-7 cells. Interestingly, mRNA levels of p27Kip1 and Skp2 did not significantly change in estrogen-stimulated MCF-7 cells after EGCG treatments. Moreover, overexpression of Skp2 in MCF-7 cells prevented accumulation of p27Kip1 and promoted resistance to the antiproliferative effects of EGCG. This suggests that the down-regulation of the F-box protein Skp2 is the mechanism underlying p27Kip1 accumulation. Furthermore, both tamoxifen and paclitaxel significantly and synergistically enhanced the growth inhibition of MCF-7 cells by EGCG through the down-regulation of Skp2 protein. However, the down-regulation of Skp2 was not always correlate with the up-regulation of p27, suggesting that EGCG-dependent Skp2 down-regulation can influence cell growth in several ways. The therapeutic strategies designed to reduce Skp2 may therefore play an important clinical role in treatment of breast cancer cells.
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Affiliation(s)
- Hsiu-Chen Huang
- Institute of Biochemistry and Molecular Biology, National Taiwan University Medicine College, Taipei 100, Taiwan
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Miranda-Carboni GA, Krum SA, Yee K, Nava M, Deng QE, Pervin S, Collado-Hidalgo A, Galić Z, Zack JA, Nakayama K, Nakayama KI, Lane TF. A functional link between Wnt signaling and SKP2-independent p27 turnover in mammary tumors. Genes Dev 2008; 22:3121-34. [PMID: 19056892 PMCID: PMC2593606 DOI: 10.1101/gad.1692808] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2008] [Accepted: 09/12/2008] [Indexed: 11/24/2022]
Abstract
Loss of the CDK inhibitor p27(KIP1) is widely linked with poor prognosis in human cancer. In Wnt10b-expressing mammary tumors, levels of p27(KIP1) were extremely low; conversely, Wnt10b-null mammary cells expressed high levels of this protein, suggesting Wnt-dependent regulation of p27(KIP1). Interestingly we found that Wnt-induced turnover of p27(KIP1) was independent from classical SCF(SKP2)-mediated degradation in both mouse and human cells. Instead, turnover required Cullin 4A and Cullin 4B, components of an alternative E3 ubiquitin ligase induced in response to active Wnt signaling. We found that CUL4A was a novel Wnt target gene in both mouse and human cells and that CUL4A physically interacted with p27(KIP1) in Wnt-responding cells. We further demonstrated that both Cul4A and Cul4B were required for Wnt-induced p27(KIP1) degradation and S-phase progression. CUL4A and CUL4B are therefore components of a conserved Wnt-induced proteasome targeting (WIPT) complex that regulates p27(KIP1) levels and cell cycle progression in mammalian cells.
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Affiliation(s)
- Gustavo A. Miranda-Carboni
- Department of Obstetrics and Gynecology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Susan A. Krum
- Department of Orthopaedic Surgery, University of California at Los Angeles-Orthopaedic Hospital, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Kathleen Yee
- Department of Obstetrics and Gynecology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Miguel Nava
- Department of Obstetrics and Gynecology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Qiming E. Deng
- Department of Obstetrics and Gynecology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Shehla Pervin
- Department of Obstetrics and Gynecology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Alicia Collado-Hidalgo
- Department of Obstetrics and Gynecology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Zoran Galić
- Department of Medicine, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Jerome A. Zack
- Department of Medicine, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California 90095, USA
- Department of Microbiology, Immunology and Molecular Genetics, University of California at Los Angeles, Los Angeles, California 90095, USA
| | - Keiko Nakayama
- Department of Developmental Biology, Center for Translational and Advance Animal Research, Graduate School of Medicine Tohoku University, Aoba-ku Sendai 980-8575, Japan
| | - Keiichi I. Nakayama
- Department of Developmental Biology, Center for Translational and Advance Animal Research, Graduate School of Medicine Tohoku University, Aoba-ku Sendai 980-8575, Japan
- Department of Molecular and Cellular Biology, Medical Institute of Bioregulation, Kyushu University, Higashi-ku, Fukuoka 812-8582, Japan
| | - Timothy F. Lane
- Department of Obstetrics and Gynecology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California 90095, USA
- Department of Orthopaedic Surgery, University of California at Los Angeles-Orthopaedic Hospital, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California 90095, USA
- Department of Biological Chemistry, University of California at Los Angeles, Los Angeles, California 90095, USA
- Jonsson Comprehensive Cancer Center, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California 90095, USA
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Extracellular signal-regulated kinase 2 (ERK2) phosphorylation sites and docking domain on the nuclear pore complex protein Tpr cooperatively regulate ERK2-Tpr interaction. Mol Cell Biol 2008; 28:6954-66. [PMID: 18794356 DOI: 10.1128/mcb.00925-08] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Identifying direct substrates of mitogen-activated protein kinases (MAPKs) and understanding how those substrates are selected is central to understanding how these ubiquitously activated enzymes generate diverse biological responses. In previous work, we identified several new candidate substrates for the MAPK ERK2 (extracellular signal-regulated kinase 2), including the nuclear pore complex protein Tpr (translocated promoter region). In this report, we identify sites on Tpr for ERK2 phosphorylation and binding and demonstrate their functional interaction. ERK2 phosphorylation and dimerization are necessary for ERK2-Tpr binding, and this occurs through a DEF (docking site for ERK2, FXF) domain on Tpr. Surprisingly, the DEF domain and the phosphorylation sites displayed positive cooperativity to promote ERK2 binding to Tpr, in contrast to substrates where phosphorylation reduces binding. Ectopic expression or depletion of Tpr resulted in decreased movement of activated ERK2 from the cytoplasm to the nucleus, implying a role for Tpr in ERK2 translocation. Collectively, the data provide direct evidence that a component of the nuclear pore complex is a bona fide substrate of ERK2 in vivo and that activated ERK2 stably associates with this substrate after phosphorylation, where it could play a continuing role in nuclear pore function. We propose that Tpr is both a substrate and a scaffold for activated ERKs.
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Bouclier C, Moine L, Hillaireau H, Marsaud V, Connault E, Opolon P, Couvreur P, Fattal E, Renoir JM. Physicochemical Characteristics and Preliminary in Vivo Biological Evaluation of Nanocapsules Loaded with siRNA Targeting Estrogen Receptor Alpha. Biomacromolecules 2008; 9:2881-90. [DOI: 10.1021/bm800664c] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Céline Bouclier
- Physico-Chimie, Pharmacotechnie, Biopharmacie, Université Paris-Sud, CNRS UMR 8612 and IFR 141, 5 rue Jean-Baptiste Clément, 92296 Châtenay-Malabry, France, and Institut Gustave Roussy, CNRS UNR 8121, Villejuif, France
| | - Laurence Moine
- Physico-Chimie, Pharmacotechnie, Biopharmacie, Université Paris-Sud, CNRS UMR 8612 and IFR 141, 5 rue Jean-Baptiste Clément, 92296 Châtenay-Malabry, France, and Institut Gustave Roussy, CNRS UNR 8121, Villejuif, France
| | - Hervé Hillaireau
- Physico-Chimie, Pharmacotechnie, Biopharmacie, Université Paris-Sud, CNRS UMR 8612 and IFR 141, 5 rue Jean-Baptiste Clément, 92296 Châtenay-Malabry, France, and Institut Gustave Roussy, CNRS UNR 8121, Villejuif, France
| | - Véronique Marsaud
- Physico-Chimie, Pharmacotechnie, Biopharmacie, Université Paris-Sud, CNRS UMR 8612 and IFR 141, 5 rue Jean-Baptiste Clément, 92296 Châtenay-Malabry, France, and Institut Gustave Roussy, CNRS UNR 8121, Villejuif, France
| | - Elisabeth Connault
- Physico-Chimie, Pharmacotechnie, Biopharmacie, Université Paris-Sud, CNRS UMR 8612 and IFR 141, 5 rue Jean-Baptiste Clément, 92296 Châtenay-Malabry, France, and Institut Gustave Roussy, CNRS UNR 8121, Villejuif, France
| | - Paule Opolon
- Physico-Chimie, Pharmacotechnie, Biopharmacie, Université Paris-Sud, CNRS UMR 8612 and IFR 141, 5 rue Jean-Baptiste Clément, 92296 Châtenay-Malabry, France, and Institut Gustave Roussy, CNRS UNR 8121, Villejuif, France
| | - Patrick Couvreur
- Physico-Chimie, Pharmacotechnie, Biopharmacie, Université Paris-Sud, CNRS UMR 8612 and IFR 141, 5 rue Jean-Baptiste Clément, 92296 Châtenay-Malabry, France, and Institut Gustave Roussy, CNRS UNR 8121, Villejuif, France
| | - Elias Fattal
- Physico-Chimie, Pharmacotechnie, Biopharmacie, Université Paris-Sud, CNRS UMR 8612 and IFR 141, 5 rue Jean-Baptiste Clément, 92296 Châtenay-Malabry, France, and Institut Gustave Roussy, CNRS UNR 8121, Villejuif, France
| | - Jack-Michel Renoir
- Physico-Chimie, Pharmacotechnie, Biopharmacie, Université Paris-Sud, CNRS UMR 8612 and IFR 141, 5 rue Jean-Baptiste Clément, 92296 Châtenay-Malabry, France, and Institut Gustave Roussy, CNRS UNR 8121, Villejuif, France
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Calvisi DF, Pinna F, Meloni F, Ladu S, Pellegrino R, Sini M, Daino L, Simile MM, De Miglio MR, Virdis P, Frau M, Tomasi ML, Seddaiu MA, Muroni MR, Feo F, Pascale RM. Dual-specificity phosphatase 1 ubiquitination in extracellular signal-regulated kinase-mediated control of growth in human hepatocellular carcinoma. Cancer Res 2008; 68:4192-200. [PMID: 18519678 DOI: 10.1158/0008-5472.can-07-6157] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Sustained activation of extracellular signal-regulated kinase (ERK) has been detected previously in numerous tumors in the absence of RAS-activating mutations. However, the molecular mechanisms responsible for ERK-unrestrained activity independent of RAS mutations remain unknown. Here, we evaluated the effects of the functional interactions of ERK proteins with dual-specificity phosphatase 1 (DUSP1), a specific inhibitor of ERK, and S-phase kinase-associated protein 2 (SKP2)/CDC28 protein kinase 1b (CKS1) ubiquitin ligase complex in human hepatocellular carcinoma (HCC). Levels of DUSP1, as assessed by real-time reverse transcription-PCR and Western blot analysis, were significantly higher in tumors with better prognosis (as defined by the length of patients' survival) when compared with both normal and nontumorous surrounding livers, whereas DUSP1 protein expression sharply declined in all HCC with poorer prognosis. In the latter HCC subtype, DUSP1 inactivation was due to either ERK/SKP2/CKS1-dependent ubiquitination or promoter hypermethylation associated with loss of heterozygosity at the DUSP1 locus. Noticeably, expression levels of DUSP1 inversely correlated with those of activated ERK, as well as with proliferation index and microvessel density, and directly with apoptosis and survival rate. Subsequent functional studies revealed that DUSP1 reactivation led to suppression of ERK, CKS1, and SKP2 activity, inhibition of proliferation and induction of apoptosis in human hepatoma cell lines. Taken together, the present data indicate that ERK achieves unrestrained activity during HCC progression by triggering ubiquitin-mediated proteolysis of its specific inhibitor DUSP1. Thus, DUSP1 may represent a valuable prognostic marker and ERK, CKS1, or SKP2 potential therapeutic targets for human HCC.
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Affiliation(s)
- Diego F Calvisi
- Department of Biomedical Sciences, Division of Experimental Pathology and Oncology, University of Sassari, 07100 Sassari, Italy
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Mitogenic Effect of Arginine Vasopressin on Adult Rat Cardiac Fibroblast: Involvement of PKC-erk1/2 Pathway. J Cardiovasc Pharmacol 2008; 52:72-81. [DOI: 10.1097/fjc.0b013e31817f36b8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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48
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Fujita T, Liu W, Doihara H, Date H, Wan Y. Dissection of the APCCdh1-Skp2 cascade in breast cancer. Clin Cancer Res 2008; 14:1966-75. [PMID: 18381934 DOI: 10.1158/1078-0432.ccr-07-1585] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Skp2 is a subunit of the SCF ubiquitin protein ligase, which plays a vital role in the control of tumorigenesis via its regulation of G(1)-S transition. Deregulation of Skp2 in various types of cancers correlates with aggressive clinical behavior and poor prognosis. Recent studies suggest that cell cycle-dependent fluctuation of Skp2 is governed by APC(Cdh1), another important E3 ligase, thereby preventing premature entry into S phase. To assess the potential role of APC(Cdh1) in tumorigenesis through proteolysis of Skp2, we have dissected the APC(Cdh1)-Skp2 cascade. EXPERIMENTAL DESIGN We manipulated the APC(Cdh1)-Skp2 cascade and examined its cellular behavior using both breast cancer and normal breast epithelial cells. Furthermore, applying immunohistochemistry, we analyzed the clinicopathologic significance of these molecules in patients with breast cancer. RESULTS Analysis of tissue arrays indicated that the percentage of samples positive for Cdh1 in breast cancer was significantly lower compared with normal breast tissues (P=0.004). Conversely, the percentage of samples scored as positive for Skp2 in cancer was significantly higher than in normal tissues (P<0.001). Moreover, prognostic studies revealed that relatively high levels of Cdh1 are associated with survivability in patients with breast cancer. In addition, depletion of Cdh1 by small interfering RNA in normal breast cells resulted in increased cellular proliferation, whereas knockdown of Skp2 significantly suppressed growth in breast cancer cells. CONCLUSIONS This study shows a correlation between Skp2 and APC(Cdh1) in breast cancer. Thus, Cdh1 may act as an important component in tumor suppression and could be considered as a novel biomarker in breast cancer.
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Affiliation(s)
- Takeo Fujita
- Department of Cell Biology and Physiology, University of Pittsburgh School of Medicine and University of Pittsburgh Cancer Institute, Pittsburgh, Pennsylvania 15213, USA
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Ravaioli A, Monti F, Regan MM, Maffini F, Mastropasqua MG, Spataro V, Castiglione-Gertsch M, Panzini I, Gianni L, Goldhirsch A, Coates A, Price KN, Gusterson BA, Viale G. p27 and Skp2 immunoreactivity and its clinical significance with endocrine and chemo-endocrine treatments in node-negative early breast cancer. Ann Oncol 2008; 19:660-8. [PMID: 18272916 DOI: 10.1093/annonc/mdm547] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Low p27 and high Skp2 immunoreactivity are associated with a poor prognosis and other poor prognostic features including resistant phenotypes and antiestrogen drug resistance. We investigated these proteins in two International Breast Cancer Study Group trials studying node-negative early breast cancer. PATIENTS AND METHODS Trial VIII compared chemotherapy followed by goserelin with either modality alone in premenopausal patients. Trial IX compared chemotherapy followed by tamoxifen with tamoxifen alone in postmenopausal patients. Central Pathology Office assessed p27 and Skp2 expression in the primary tumor by immunohistochemistry among 1631 (60%) trial patients. RESULTS p27 and Skp2 were inversely related; 13% of tumors expressed low p27 and high Skp2. Low p27 and high Skp2 were associated with unfavorable prognostic factors including larger size and higher grade tumors, absence of estrogen receptor and progesterone receptor, human epidermal growth factor receptor 2 overexpression and high Ki-67 (each P < 0.05). Low p27 and high Skp2 were not associated with disease-free survival (P = 0.42 and P = 0.48, respectively). The relative effects of chemo-endocrine versus endocrine therapy were similar regardless of p27 or Skp2. CONCLUSIONS We confirm the association of low p27 and high Skp2 with other poor prognostic features, but found no predictive or prognostic value, and therefore do not recommend routine determination of p27 and Skp2 for node-negative breast cancer.
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Affiliation(s)
- A Ravaioli
- Department of Oncology, Ospedale Infermi, Rimini and Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori, Meldola (FC) Italy.
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Cell cycle machinery: links with genesis and treatment of breast cancer. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 630:189-205. [PMID: 18637492 DOI: 10.1007/978-0-387-78818-0_12] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Loss of normal growth control is a hallmark of cancer. Thus, understanding the mechanisms of tissue-specific, normal growth regulation and the changes that occur during tumorigenesis may provide insights of both diagnostic and therapeutic importance. Control of cell proliferation in the normal mammary gland is steroid hormone (estrogen and progestin)-dependent, involves complex interactions with other hormones, growth factors and cytokines and ultimately converges on activation of three proto-oncogenes (c-Myc, cyclin D1 and cyclin E1) that are rate limiting for the G1 to S phase transition during normal cell cycle progression. Mammary epithelial cell-specific overexpression of these genes induces mammary carcinoma in mice, while cyclin D1 null mice have arrested mammary gland development and are resistant to carcinoma induced by the neu/erbB2 and ras oncogenes. Furthermore, c-Myc, cyclins D1, E1 and E2 are commonly overexpressed in primary breast cancer where elevated expression is often associated with a more aggressive disease phenotype and an adverse patient outcome. This may be due in part to overexpression of these genes conferring resistance to endocrine therapies since in vitro studies provide compelling evidence that overexpression of c-Myc and to a lesser extent cyclin D1 and cyclin E1, attenuate the growth inhibitory effects of SERMS, antiestrogens and progestins in breast cancer cells. Thus, abnormal regulation of the expression of cell cycle molecules, involved in the steroidal control of cell proliferation in the mammary gland, are likely to be directly involved in the development, progression and therapeutic responsiveness of breast cancer. Furthermore, a more detailed understanding of these pathways may identify new targets for therapeutic intervention particularly in endocrine-unresponsive and endocrine-resistant disease.
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