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Ding Z, Hagan M, Yan F, Schroer NW, Polmear J, Good-Jacobson KL, Dvorscek AR, Pitt C, O’Donnell K, Nutt SL, Zotos D, McKenzie C, Hill DL, Robinson MJ, Quast I, Koentgen F, Tarlinton DM. Ki67 deficiency impedes chromatin accessibility and BCR gene rearrangement. J Exp Med 2024; 221:e20232160. [PMID: 38842525 PMCID: PMC11157087 DOI: 10.1084/jem.20232160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 04/10/2024] [Accepted: 05/17/2024] [Indexed: 06/07/2024] Open
Abstract
The proliferation marker Ki67 has been attributed critical functions in maintaining mitotic chromosome morphology and heterochromatin organization during the cell cycle, indicating a potential role in developmental processes requiring rigid cell-cycle control. Here, we discovered that despite normal fecundity and organogenesis, germline deficiency in Ki67 resulted in substantial defects specifically in peripheral B and T lymphocytes. This was not due to impaired cell proliferation but rather to early lymphopoiesis at specific stages where antigen-receptor gene rearrangements occurred. We identified that Ki67 was required for normal global chromatin accessibility involving regulatory regions of genes critical for checkpoint stages in B cell lymphopoiesis. In line with this, mRNA expression of Rag1 was diminished and gene rearrangement was less efficient in the absence of Ki67. Transgenes encoding productively rearranged immunoglobulin heavy and light chains complemented Ki67 deficiency, completely rescuing early B cell development. Collectively, these results identify a unique contribution from Ki67 to somatic antigen-receptor gene rearrangement during lymphopoiesis.
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Affiliation(s)
- Zhoujie Ding
- Department of Immunology, Central Clinical School, Monash University, Melbourne, Australia
| | | | - Feng Yan
- Bioinformatics Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
| | - Nick W.Y. Schroer
- Department of Immunology, Central Clinical School, Monash University, Melbourne, Australia
| | - Jack Polmear
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
- Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Australia
| | - Kim L. Good-Jacobson
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
- Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, Australia
| | - Alexandra R. Dvorscek
- Department of Immunology, Central Clinical School, Monash University, Melbourne, Australia
| | - Catherine Pitt
- Department of Immunology, Central Clinical School, Monash University, Melbourne, Australia
| | - Kristy O’Donnell
- Department of Immunology, Central Clinical School, Monash University, Melbourne, Australia
| | - Stephen L. Nutt
- Immunology Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Australia
- Department of Medical Biology, University of Melbourne, Parkville, Australia
| | - Dimitra Zotos
- Department of Immunology, Central Clinical School, Monash University, Melbourne, Australia
| | - Craig McKenzie
- Department of Immunology, Central Clinical School, Monash University, Melbourne, Australia
| | - Danika L. Hill
- Department of Immunology, Central Clinical School, Monash University, Melbourne, Australia
| | - Marcus J. Robinson
- Department of Immunology, Central Clinical School, Monash University, Melbourne, Australia
| | - Isaak Quast
- Department of Immunology, Central Clinical School, Monash University, Melbourne, Australia
| | | | - David M. Tarlinton
- Department of Immunology, Central Clinical School, Monash University, Melbourne, Australia
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Borisova E, Newman AG, Couce Iglesias M, Dannenberg R, Schaub T, Qin B, Rusanova A, Brockmann M, Koch J, Daniels M, Turko P, Jahn O, Kaplan DR, Rosário M, Iwawaki T, Spahn CMT, Rosenmund C, Meierhofer D, Kraushar ML, Tarabykin V, Ambrozkiewicz MC. Protein translation rate determines neocortical neuron fate. Nat Commun 2024; 15:4879. [PMID: 38849354 PMCID: PMC11161512 DOI: 10.1038/s41467-024-49198-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 05/24/2024] [Indexed: 06/09/2024] Open
Abstract
The mammalian neocortex comprises an enormous diversity regarding cell types, morphology, and connectivity. In this work, we discover a post-transcriptional mechanism of gene expression regulation, protein translation, as a determinant of cortical neuron identity. We find specific upregulation of protein synthesis in the progenitors of later-born neurons and show that translation rates and concomitantly protein half-lives are inherent features of cortical neuron subtypes. In a small molecule screening, we identify Ire1α as a regulator of Satb2 expression and neuronal polarity. In the developing brain, Ire1α regulates global translation rates, coordinates ribosome traffic, and the expression of eIF4A1. Furthermore, we demonstrate that the Satb2 mRNA translation requires eIF4A1 helicase activity towards its 5'-untranslated region. Altogether, we show that cortical neuron diversity is generated by mechanisms operating beyond gene transcription, with Ire1α-safeguarded proteostasis serving as an essential regulator of brain development.
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Affiliation(s)
- Ekaterina Borisova
- Institute of Cell Biology and Neurobiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Andrew G Newman
- Institute of Cell Biology and Neurobiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Marta Couce Iglesias
- Max Planck Institute for Molecular Genetics, Ihnestraße 63-73, 14195, Berlin, Germany
| | - Rike Dannenberg
- Institute of Cell Biology and Neurobiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Theres Schaub
- Institute of Cell Biology and Neurobiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Bo Qin
- Max Planck Institute for Molecular Genetics, Ihnestraße 63-73, 14195, Berlin, Germany
| | - Alexandra Rusanova
- Institute of Cell Biology and Neurobiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
- Tomsk National Research Medical Center of the Russian Academy of Sciences, Research Institute of Medical Genetics, Tomsk, Russia
| | - Marisa Brockmann
- Institute of Neurophysiology, Charité-Universitätsmedizin Berlin, 10117, Berlin, Germany
| | - Janina Koch
- Institute of Cell Biology and Neurobiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Marieatou Daniels
- Institute of Cell Biology and Neurobiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Paul Turko
- Institute of Integrative Neuroanatomy, Charité-Universitätsmedizin Berlin, 10117, Berlin, Germany
| | - Olaf Jahn
- Neuroproteomics Group, Department of Molecular Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Hermann-Rein-Str. 3, 37075, Göttingen, Germany
- Translational Neuroproteomics Group, Department of Psychiatry and Psychotherapy, University Medical Center Göttingen, Georg-August-University, Von-Siebold-Str. 5, 37075, Göttingen, Germany
| | - David R Kaplan
- Program in Neurosciences and Mental Health, Hospital for Sick Children and Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Marta Rosário
- Institute of Cell Biology and Neurobiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Takao Iwawaki
- Medical Research Institute, Kanazawa Medical University, 1-1 Daigaku, Uchinada, Kahoku, Ishikawa, 920-0293, Japan
| | - Christian M T Spahn
- Institute of Medical Physics and Biophysics, Charité-Universitätsmedizin Berlin, 10117, Berlin, Germany
| | - Christian Rosenmund
- Institute of Neurophysiology, Charité-Universitätsmedizin Berlin, 10117, Berlin, Germany
| | - David Meierhofer
- Max Planck Institute for Molecular Genetics, Ihnestraße 63-73, 14195, Berlin, Germany
| | - Matthew L Kraushar
- Max Planck Institute for Molecular Genetics, Ihnestraße 63-73, 14195, Berlin, Germany
| | - Victor Tarabykin
- Institute of Cell Biology and Neurobiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany.
| | - Mateusz C Ambrozkiewicz
- Institute of Cell Biology and Neurobiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany.
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3
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Qiao X, Gu X, Liu Y, Shu X, Ai G, Qian S, Liu L, He X, Zhang J. MRI Radiomics-Based Machine Learning Models for Ki67 Expression and Gleason Grade Group Prediction in Prostate Cancer. Cancers (Basel) 2023; 15:4536. [PMID: 37760505 PMCID: PMC10526397 DOI: 10.3390/cancers15184536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 09/02/2023] [Accepted: 09/11/2023] [Indexed: 09/29/2023] Open
Abstract
PURPOSE The Ki67 index and the Gleason grade group (GGG) are vital prognostic indicators of prostate cancer (PCa). This study investigated the value of biparametric magnetic resonance imaging (bpMRI) radiomics feature-based machine learning (ML) models in predicting the Ki67 index and GGG of PCa. METHODS A total of 122 patients with pathologically proven PCa who had undergone preoperative MRI were retrospectively included. Radiomics features were extracted from T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), and apparent diffusion coefficient (ADC) maps. Then, recursive feature elimination (RFE) was applied to remove redundant features. ML models for predicting Ki67 expression and GGG were constructed based on bpMRI and different algorithms, including logistic regression (LR), support vector machine (SVM), random forest (RF), and K-nearest neighbor (KNN). The performances of different models were evaluated with receiver operating characteristic (ROC) analysis. In addition, a joint analysis of Ki67 expression and GGG was performed by assessing their Spearman correlation and calculating the diagnostic accuracy for both indices. RESULTS The ML model based on LR and ADC + T2 (LR_ADC + T2, AUC = 0.8882) performed best in predicting Ki67 expression, and ADC_wavelet-LHH_firstorder_Maximum had the highest feature weighting. The SVM_DWI + T2 (AUC = 0.9248) performed best in predicting GGG, and DWI_wavelet HLL_glcm_SumAverage had the highest feature weighting. The Ki67 and GGG exhibited a weak positive correlation (r = 0.382, p < 0.001), and LR_ADC + DWI had the highest diagnostic accuracy in predicting both (0.6230). CONCLUSION The proposed ML models are suitable for predicting both Ki67 expression and GGG in PCa. This algorithm could be used to identify indolent or invasive PCa with a noninvasive, repeatable, and accurate diagnostic method.
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Affiliation(s)
- Xiaofeng Qiao
- Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 400010, China; (X.Q.); (X.G.); (Y.L.); (X.S.); (G.A.)
| | - Xiling Gu
- Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 400010, China; (X.Q.); (X.G.); (Y.L.); (X.S.); (G.A.)
| | - Yunfan Liu
- Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 400010, China; (X.Q.); (X.G.); (Y.L.); (X.S.); (G.A.)
| | - Xin Shu
- Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 400010, China; (X.Q.); (X.G.); (Y.L.); (X.S.); (G.A.)
| | - Guangyong Ai
- Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 400010, China; (X.Q.); (X.G.); (Y.L.); (X.S.); (G.A.)
| | - Shuang Qian
- Big Data and Software Engineering College, Chongqing University, Chongqing 400000, China; (S.Q.); (L.L.)
| | - Li Liu
- Big Data and Software Engineering College, Chongqing University, Chongqing 400000, China; (S.Q.); (L.L.)
| | - Xiaojing He
- Department of Radiology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 400010, China; (X.Q.); (X.G.); (Y.L.); (X.S.); (G.A.)
| | - Jingjing Zhang
- Departments of Diagnostic Radiology, National University of Singapore, Singapore 119074, Singapore
- Clinical Imaging Research Centre, Centre for Translational Medicine, National University of Singapore, Singapore 117599, Singapore
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Dupont C, Chahar D, Trullo A, Gostan T, Surcis C, Grimaud C, Fisher D, Feil R, Llères D. Evidence for low nanocompaction of heterochromatin in living embryonic stem cells. EMBO J 2023:e110286. [PMID: 37082862 DOI: 10.15252/embj.2021110286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 03/22/2023] [Accepted: 03/29/2023] [Indexed: 04/22/2023] Open
Abstract
Despite advances in the identification of chromatin regulators and genome interactions, the principles of higher-order chromatin structure have remained elusive. Here, we applied FLIM-FRET microscopy to analyse, in living cells, the spatial organisation of nanometre range proximity between nucleosomes, which we called "nanocompaction." Both in naive embryonic stem cells (ESCs) and in ESC-derived epiblast-like cells (EpiLCs), we find that, contrary to expectations, constitutive heterochromatin is much less compacted than bulk chromatin. The opposite was observed in fixed cells. HP1α knockdown increased nanocompaction in living ESCs, but this was overridden by loss of HP1β, indicating the existence of a dynamic HP1-dependent low compaction state in pluripotent cells. Depletion of H4K20me2/3 abrogated nanocompaction, while increased H4K20me3 levels accompanied the nuclear reorganisation during EpiLCs induction. Finally, the knockout of the nuclear cellular-proliferation marker Ki-67 strongly reduced both interphase and mitotic heterochromatin nanocompaction in ESCs. Our data indicate that, contrary to prevailing models, heterochromatin is not highly compacted at the nanoscale but resides in a dynamic low nanocompaction state that depends on H4K20me2/3, the balance between HP1 isoforms, and Ki-67.
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Affiliation(s)
- Claire Dupont
- Institute of Molecular Genetics of Montpellier (IGMM), CNRS, University of Montpellier, Montpellier, France
| | - Dhanvantri Chahar
- Institute of Molecular Genetics of Montpellier (IGMM), CNRS, University of Montpellier, Montpellier, France
| | - Antonio Trullo
- Institute of Molecular Genetics of Montpellier (IGMM), CNRS, University of Montpellier, Montpellier, France
| | - Thierry Gostan
- Institute of Molecular Genetics of Montpellier (IGMM), CNRS, University of Montpellier, Montpellier, France
| | - Caroline Surcis
- Institute of Molecular Genetics of Montpellier (IGMM), CNRS, University of Montpellier, Montpellier, France
| | - Charlotte Grimaud
- Institute of Human Genetics (IGH), CNRS, University of Montpellier, Montpellier, France
| | - Daniel Fisher
- Institute of Molecular Genetics of Montpellier (IGMM), CNRS, University of Montpellier, Montpellier, France
| | - Robert Feil
- Institute of Molecular Genetics of Montpellier (IGMM), CNRS, University of Montpellier, Montpellier, France
| | - David Llères
- Institute of Molecular Genetics of Montpellier (IGMM), CNRS, University of Montpellier, Montpellier, France
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Andrés-Sánchez N, Fisher D, Krasinska L. Physiological functions and roles in cancer of the proliferation marker Ki-67. J Cell Sci 2022; 135:275629. [PMID: 35674256 DOI: 10.1242/jcs.258932] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
What do we know about Ki-67, apart from its usefulness as a cell proliferation biomarker in histopathology? Discovered in 1983, the protein and its regulation of expression and localisation throughout the cell cycle have been well characterised. However, its function and molecular mechanisms have received little attention and few answers. Although Ki-67 has long been thought to be required for cell proliferation, recent genetic studies have conclusively demonstrated that this is not the case, as loss of Ki-67 has little or no impact on cell proliferation. In contrast, Ki-67 is important for localising nucleolar material to the mitotic chromosome periphery and for structuring perinucleolar heterochromatin, and emerging data indicate that it also has critical roles in cancer development. However, its mechanisms of action have not yet been fully identified. Here, we review recent findings and propose the hypothesis that Ki-67 is involved in structuring cellular sub-compartments that assemble by liquid-liquid phase separation. At the heterochromatin boundary, this may control access of chromatin regulators, with knock-on effects on gene expression programmes. These changes allow adaptation of the cell to its environment, which, for cancer cells, is a hostile one. We discuss unresolved questions and possible avenues for future exploration.
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Affiliation(s)
- Nuria Andrés-Sánchez
- Institute of Molecular Genetics of Montpellier (IGMM), University of Montpellier, CNRS, INSERM, 34293 Montpellier, France.,Equipe Labellisée LIGUE 2018, Ligue Nationale Contre le Cancer, 75013 Paris, France
| | - Daniel Fisher
- Institute of Molecular Genetics of Montpellier (IGMM), University of Montpellier, CNRS, INSERM, 34293 Montpellier, France.,Equipe Labellisée LIGUE 2018, Ligue Nationale Contre le Cancer, 75013 Paris, France
| | - Liliana Krasinska
- Institute of Molecular Genetics of Montpellier (IGMM), University of Montpellier, CNRS, INSERM, 34293 Montpellier, France.,Equipe Labellisée LIGUE 2018, Ligue Nationale Contre le Cancer, 75013 Paris, France
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Jayathilake AG, Kadife E, Kuol N, Luwor RB, Nurgali K, Su XQ. Krill oil supplementation reduces the growth of CT-26 orthotopic tumours in Balb/c mice. BMC Complement Med Ther 2022; 22:34. [PMID: 35120511 PMCID: PMC8817584 DOI: 10.1186/s12906-022-03521-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 01/25/2022] [Indexed: 12/09/2022] Open
Abstract
Background We have previously reported that the free fatty acid extract (FFAE) of krill oil (KO) significantly inhibits the proliferation and migration, and induces apoptosis of colorectal cancer (CRC) cells. This study aimed to investigate the in vivo efficacy of various doses of KO supplementation on the inhibition of CRC tumour growth, molecular markers of proliferation, angiogenesis, apoptosis, the epidermal growth factor receptor (EGFR) and its downstream molecular signalling. Methods Male Balb/c mice were randomly divided into four groups with five in each group. The control (untreated) group received standard chow diet; and other three groups received KO supplementation at 5%, 10%, and 15% of their daily dietary intake respectively for three weeks before and after the orthotopic implantation of CT-26 CRC cells in their caecum. The expression of cell proliferation marker Ki-67 and angiogenesis marker CD-31 were assessed by immunohistochemistry. The expression of EGFR, phosphorylated EGFR (pEGFR), protein kinase B (AKT), pAKT, extracellular signal-regulated kinase (ERK1/2), pERK1/2, cleaved caspase-7, cleaved poly (ADP-ribose) polymerase (PARP), and DNA/RNA damage were determined by western blot. Results KO supplementation reduced the CRC tumour growth in a dose-dependent manner; with 15% of KO being the most effective in reduction of tumour weight and volume (68.5% and 68.3% respectively, P < 0.001), inhibition of cell proliferation by 69.9% (P < 0.001) and microvessel density by 72.7% (P < 0.001). The suppressive effects of KO on EGFR and its downstream signalling, ERK1/2 and AKT, were consistent with our previous in vitro observations. Furthermore, KO exhibited pro-apoptotic effects on tumour cells as indicated by an increase in the expression of cleaved PARP by 3.9-fold and caspase-7 by 8.9-fold. Conclusions This study has demonstrated that KO supplementation reduces CRC tumour growth by inhibiting cancer cell proliferation and blood vessel formation and inducing apoptosis of tumour cells. These anti-cancer effects are associated with the downregulation of the EGFR signalling pathway and activation of caspase-7, PARP cleavage, and DNA/RNA damage. Supplementary Information The online version contains supplementary material available at 10.1186/s12906-022-03521-4.
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Affiliation(s)
| | - Elif Kadife
- Institute for Health and Sport, Victoria University, Melbourne, 8001, Australia
| | - Nyanbol Kuol
- Institute for Health and Sport, Victoria University, Melbourne, 8001, Australia
| | - Rodney Brain Luwor
- Department of Surgery, The Royal Melbourne Hospital, The University of Melbourne, Parkville, Australia
| | - Kulmira Nurgali
- Institute for Health and Sport, Victoria University, Melbourne, 8001, Australia.,Department of Medicine, Western Health, The University of Melbourne, Melbourne, Australia.,Regenerative Medicine and Stem Cells Program, Australian Institute for Musculoskeletal Sciences (AIMSS), Melbourne, Australia
| | - Xiao Qun Su
- Institute for Health and Sport, Victoria University, Melbourne, 8001, Australia.
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Proliferation in pleomorphic adenoma: Lights and shadow on this parameter, in a neoplasm showing unpredictable behavior-An immunohistochemical study and review of the literature. Pathol Res Pract 2021; 232:153748. [PMID: 35094844 DOI: 10.1016/j.prp.2021.153748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 12/18/2021] [Accepted: 12/20/2021] [Indexed: 11/21/2022]
Abstract
BACKGROUND Pleomorphic adenoma accounts for the majority of benign tumors of the salivary gland. It is also called mixed tumor because it is composed by ductal epithelial and myoepithelial cells, variably intermixed within a chondromyxoid stroma. The recurrence rate is around 3.4% and 6.3%, respectively at 5 and 10 years and, to date, there are no valuable predictive factors. Aim of our study was to assess the role of Ki67 proliferative index in our cases and through meta-analysis. METHODS Immunohistochemistry with Ki67 antibody was performed on 28 cases. A manual count of the signal was performed, to establish the proliferative activity. Statistical tests were applied to assess the correlation between the score and clinico-pathologic parameters. Further data were extrapolated from studies published on Pubmed, Cochrane and Web of Science database. RESULTS Higher values of Ki67 were found among cases with larger size (p value = 0.0061) and showing greater cellularity (p value=0.0004). 19 papers were selected from the bibliographic search, concerning a total of 1187 patients affected by pleomorphic adenoma. In most of them, a higher Ki67 was detected among relapsing forms but results were controversial. In each study, several count methods were applied. CONCLUSION The role of Ki67 in pleomorphic adenoma of the salivary glands remains unclear. The lack of homogeneity of the data makes it very difficult to standardize them in order to draw a conclusion. It would therefore be desirable to carry out a comparison study of the various possible methods of Ki67 counting.
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Distribution and Appearance of Ki-67, IL-1α, IL-10, and PGP 9.5 in Reinke's Oedema-Affected Larynx Tissue Compared with Control Tissue. Life (Basel) 2021; 11:life11121379. [PMID: 34947910 PMCID: PMC8706443 DOI: 10.3390/life11121379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 12/05/2021] [Accepted: 12/07/2021] [Indexed: 11/19/2022] Open
Abstract
Smoking, laryngopharyngeal reflux, and vocal fold abuse can promote the development of Reinke’s oedema, leading to vocal fold dysfunction and injury. The aim of the work was to investigate the appearance and distribution of proliferation marker Ki-67 (Ki-67), interleukin 10 (IL-10), interleukin 1 alpha (IL-1α), and protein gene peptide 9.5 (PGP 9.5) in Reinke’s oedema-affected larynx tissue. Methods: A routine histological and immunohistochemical Reinke’s oedema and control group patient analysis was conducted. We used the biotin–streptavidin biochemical method to detect Ki-67, IL-10, IL-1α, and PGP 9.5 The semiquantitative grading method was used to evaluate immunoreactive cells’ appearance and local distribution. A Mann–Whitney U test and Spearman’s rank coefficient were performed. Results: A low positive correlation between IL-1α epithelial and subepithelial immunoreactive cells in the patient group was found. Mann–Whitney U tests revealed significant patient and control group immunoreactive marker differences. All examined markers showed a higher number of immunoreactive structures in the patient group. Conclusions: Intensive proliferation of the surface epithelium was observed in patient tissues. The notable increase in IL-10 positive structures indicates the dominant anti-inflammatory tissue response. An increased number of IL-1α structures in the larynx epithelium and subepithelium in the patient group is linked to inflammation, proliferation, and tissue remodelling. The PGP 9.5 expression increase is involved in the morphopathogenesis of Reinke’s oedema.
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La T, Chen S, Guo T, Zhao XH, Teng L, Li D, Carnell M, Zhang YY, Feng YC, Cole N, Brown AC, Zhang D, Dong Q, Wang JY, Cao H, Liu T, Thorne RF, Shao FM, Zhang XD, Jin L. Visualization of endogenous p27 and Ki67 reveals the importance of a c-Myc-driven metabolic switch in promoting survival of quiescent cancer cells. Am J Cancer Res 2021; 11:9605-9622. [PMID: 34646389 PMCID: PMC8490506 DOI: 10.7150/thno.63763] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 09/07/2021] [Indexed: 12/11/2022] Open
Abstract
Rationale: Recurrent and metastatic cancers often undergo a period of dormancy, which is closely associated with cellular quiescence, a state whereby cells exit the cell cycle and are reversibly arrested in G0 phase. Curative cancer treatment thus requires therapies that either sustain the dormant state of quiescent cancer cells, or preferentially, eliminate them. However, the mechanisms responsible for the survival of quiescent cancer cells remain obscure. Methods: Dual genome-editing was carried out using a CRISPR/Cas9-based system to label endogenous p27 and Ki67 with the green and red fluorescent proteins EGFP and mCherry, respectively, in melanoma cells. Analysis of transcriptomes of isolated EGFP-p27highmCherry-Ki67low quiescent cells was conducted at bulk and single cell levels using RNA-sequencing. The extracellular acidification rate and oxygen consumption rate were measured to define metabolic phenotypes. SiRNA and inducible shRNA knockdown, chromatin immunoprecipitation and luciferase reporter assays were employed to elucidate mechanisms of the metabolic switch in quiescent cells. Results: Dual labelling of endogenous p27 and Ki67 with differentiable fluorescent probes allowed for visualization, isolation, and analysis of viable p27highKi67low quiescent cells. Paradoxically, the proto-oncoprotein c-Myc, which commonly drives malignant cell cycle progression, was expressed at relatively high levels in p27highKi67low quiescent cells and supported their survival through promoting mitochondrial oxidative phosphorylation (OXPHOS). In this context, c-Myc selectively transactivated genes encoding OXPHOS enzymes, including subunits of isocitric dehydrogenase 3 (IDH3), whereas its binding to cell cycle progression gene promoters was decreased in quiescent cells. Silencing of c-Myc or the catalytic subunit of IDH3, IDH3α, preferentially killed quiescent cells, recapitulating the effect of treatment with OXPHOS inhibitors. Conclusion: These results establish a rigorous experimental system for investigating cellular quiescence, uncover the high selectivity of c-Myc in activating OXPHOS genes in quiescent cells, and propose OXPHOS targeting as a potential therapeutic avenue to counter cancer cells in quiescence.
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Yoneda M, Nakagawa T, Hattori N, Ito T. The nucleolus from a liquid droplet perspective. J Biochem 2021; 170:153-162. [PMID: 34358306 DOI: 10.1093/jb/mvab090] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 07/27/2021] [Indexed: 11/14/2022] Open
Abstract
The nucleolus is a membrane-less organelle sequestered from the nucleus by liquid droplet formation through a liquid-liquid phase separation (LLPS). It plays important roles in cell homeostasis through its internal thermodynamic changes. Reversible nucleolar transitions between coalescence and dispersion are dependent on the concentrations, conformations, and interactions of its molecular liquid droplet-forming components, including DNA, RNA, and protein. The liquid droplet-like properties of the nucleolus enable its diverse dynamic roles. The liquid droplet formation mechanism, by which the nucleolus is sequestered from the nucleoplasm despite the absence of a membrane, explains a number of complex nucleolar functions.
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Affiliation(s)
- Mitsuhiro Yoneda
- Department of Biochemistry, Nagasaki University School of Medicine, Nagasaki, 852-8523, JAPAN.,Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, 852-8523, JAPAN
| | - Takeya Nakagawa
- Department of Biochemistry, Nagasaki University School of Medicine, Nagasaki, 852-8523, JAPAN.,Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, 852-8523, JAPAN
| | - Naoko Hattori
- Department of Biochemistry, Nagasaki University School of Medicine, Nagasaki, 852-8523, JAPAN.,Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, 852-8523, JAPAN
| | - Takashi Ito
- Department of Biochemistry, Nagasaki University School of Medicine, Nagasaki, 852-8523, JAPAN.,Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, 852-8523, JAPAN
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11
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Remnant L, Kochanova NY, Reid C, Cisneros-Soberanis F, Earnshaw WC. The intrinsically disorderly story of Ki-67. Open Biol 2021; 11:210120. [PMID: 34375547 PMCID: PMC8354752 DOI: 10.1098/rsob.210120] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 07/13/2021] [Indexed: 01/14/2023] Open
Abstract
Ki-67 is one of the most famous marker proteins used by histologists to identify proliferating cells. Indeed, over 30 000 articles referring to Ki-67 are listed on PubMed. Here, we review some of the current literature regarding the protein. Despite its clinical importance, our knowledge of the molecular biology and biochemistry of Ki-67 is far from complete, and its exact molecular function(s) remain enigmatic. Furthermore, reports describing Ki-67 function are often contradictory, and it has only recently become clear that this proliferation marker is itself dispensable for cell proliferation. We discuss the unusual organization of the protein and its mRNA and how they relate to various models for its function. In particular, we focus on ways in which the intrinsically disordered structure of Ki-67 might aid in the assembly of the still-mysterious mitotic chromosome periphery compartment by controlling liquid-liquid phase separation of nucleolar proteins and RNAs.
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Affiliation(s)
- Lucy Remnant
- Wellcome Centre for Cell Biology, University of Edinburgh, ICB, Michael Swann Building, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Natalia Y. Kochanova
- Wellcome Centre for Cell Biology, University of Edinburgh, ICB, Michael Swann Building, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Caitlin Reid
- Wellcome Centre for Cell Biology, University of Edinburgh, ICB, Michael Swann Building, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Fernanda Cisneros-Soberanis
- Wellcome Centre for Cell Biology, University of Edinburgh, ICB, Michael Swann Building, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - William C. Earnshaw
- Wellcome Centre for Cell Biology, University of Edinburgh, ICB, Michael Swann Building, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
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12
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Guadagno E, D'Avella E, Cappabianca P, Colao A, Del Basso De Caro M. Ki67 in endocrine neoplasms: to count or not to count, this is the question! A systematic review from the English language literature. J Endocrinol Invest 2020; 43:1429-1445. [PMID: 32415572 DOI: 10.1007/s40618-020-01275-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 04/23/2020] [Indexed: 12/11/2022]
Abstract
BACKGROUND Endocrine neoplasms are generally slow-growing tumors that can show hormonal activity and give metastases. In most cases they are benign and clearly malignant forms are easy to diagnose. However, borderline forms may occur and be, for the pathologists, very difficult to classify. In these cases, there is a strong need to identify factors that may aid. Official classification systems for endocrine neoplasms are based on the evaluation of proliferation and, in most cases, they rely on mitotic count. In support, the study of Ki67 is carried out which, however, has not yet been included in any official classification system, except for neuroendocrine neoplasms of the gastro-entero-pancreatic tract. PURPOSE The aim of the present study was to investigate the proven or unproven role of Ki67 in endocrine neoplasms, in different districts, in order to bring to light the substantial differences, in terms of proliferation, existing between neoplasms so similar, but at the same time, so different. METHODS A thorough search of English language literature was performed, looking for articles concerning Ki67 in five endocrine neoplasms (pituitary adenomas, thyroid neoplasms, adrenocortical neoplasms, pheochromocytomas and paragangliomas). RESULTS From 2170, 236 articles were selected and it was seen that the endocrine neoplasm in which Ki67 was most studied was the pituitary, where it still shows a controversial role. In other neoplasms different roles were identified. CONCLUSION The pathologist should be aware of the contribution that this proliferative marker can give to the diagnosis and, sometimes, to the therapy selection, for the clinician.
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Affiliation(s)
- E Guadagno
- Pathology Section, Department of Advanced Biomedical Sciences, "Federico II" University of Naples, Via Pansini 5, 80131, Naples, Italy.
| | - E D'Avella
- Division of Neurosurgery, Department of Neurosciences, Reproductive and Odontostomatological Sciences, "Federico II" University of Naples, Via Pansini 5, 80131, Naples, Italy
| | - P Cappabianca
- Division of Neurosurgery, Department of Neurosciences, Reproductive and Odontostomatological Sciences, "Federico II" University of Naples, Via Pansini 5, 80131, Naples, Italy
| | - A Colao
- Endocrinology Section, Department of Clinic Medicine and Surgery, "Federico II" University of Naples, Via Pansini 5, 80131, Naples, Italy
| | - M Del Basso De Caro
- Pathology Section, Department of Advanced Biomedical Sciences, "Federico II" University of Naples, Via Pansini 5, 80131, Naples, Italy
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13
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Meyer-Nava S, Nieto-Caballero VE, Zurita M, Valadez-Graham V. Insights into HP1a-Chromatin Interactions. Cells 2020; 9:E1866. [PMID: 32784937 PMCID: PMC7465937 DOI: 10.3390/cells9081866] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/18/2020] [Accepted: 07/21/2020] [Indexed: 12/17/2022] Open
Abstract
Understanding the packaging of DNA into chromatin has become a crucial aspect in the study of gene regulatory mechanisms. Heterochromatin establishment and maintenance dynamics have emerged as some of the main features involved in genome stability, cellular development, and diseases. The most extensively studied heterochromatin protein is HP1a. This protein has two main domains, namely the chromoshadow and the chromodomain, separated by a hinge region. Over the years, several works have taken on the task of identifying HP1a partners using different strategies. In this review, we focus on describing these interactions and the possible complexes and subcomplexes associated with this critical protein. Characterization of these complexes will help us to clearly understand the implications of the interactions of HP1a in heterochromatin maintenance, heterochromatin dynamics, and heterochromatin's direct relationship to gene regulation and chromatin organization.
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Affiliation(s)
| | | | | | - Viviana Valadez-Graham
- Instituto de Biotecnología, Departamento de Genética del Desarrollo y Fisiología Molecular, Universidad Nacional Autónoma de México, Cuernavaca Morelos 62210, Mexico; (S.M.-N.); (V.E.N.-C.); (M.Z.)
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14
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Pawelczyk K, Piotrowska A, Ciesielska U, Jablonska K, Gletzel-Plucinska N, Grzegrzolka J, Podhorska-Okolow M, Dziegiel P, Nowinska K. Role of PD-L1 Expression in Non-Small Cell Lung Cancer and Their Prognostic Significance according to Clinicopathological Factors and Diagnostic Markers. Int J Mol Sci 2019; 20:ijms20040824. [PMID: 30769852 PMCID: PMC6413136 DOI: 10.3390/ijms20040824] [Citation(s) in RCA: 110] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 02/10/2019] [Accepted: 02/12/2019] [Indexed: 12/12/2022] Open
Abstract
Background: The latest immunotherapy, used in the treatment of non-small cell lung cancer (NSCLC), uses monoclonal antibodies directed against programmed death ligand 1 (PD-L1) to inhibit its interaction with the PD-1 receptor. Elevated levels of PD-L1 expression were observed on NSCLC cells. The association between PD-L1 expression and clinicopathological features is still unclear. Therefore, we examined this relationship and also compare PD-L1 expression levels with Ki-67, p63 and TTF-1. Methods: 866 samples of NSCLCs were used to prepare tissue microarrays (TMAs) on which immunohistochemical (IHC) reactions were performed. Changes in the level of CD274 (PD-L1) gene expression in 62 NSCLC tumors were tested in relation to 14 normal lung tissues by real-time PCR reactions (RT-PCR). Results: PD-L1 expression was observed in 32.6% of NSCLCs. PD-L1 expression was increased in higher malignancy grades (G) (p < 0.0001) and in higher lymph node status (pN) (p = 0.0428). The patients with low PD-L1 expression had longer overall survival compared to the group with high expression (p = 0.0332) in adenocarcinoma (AC) only. Conclusions: PD-L1 expression seems to be associated with increased tumor proliferation and aggressiveness as well as shorter patient survival in NSCLC, predominantly in the AC group.
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Affiliation(s)
- Konrad Pawelczyk
- Department of Thoracic Surgery, Wroclaw Medical University, Wroclaw 53-439, Poland.
- Department of Thoracic Surgery, Lower Silesian Centre of Lung Diseases, Wroclaw 53-439, Poland.
| | - Aleksandra Piotrowska
- Department of Human Morphology and Embryology, Wroclaw Medical University, Wroclaw 50-368, Poland.
| | - Urszula Ciesielska
- Department of Human Morphology and Embryology, Wroclaw Medical University, Wroclaw 50-368, Poland.
| | - Karolina Jablonska
- Department of Human Morphology and Embryology, Wroclaw Medical University, Wroclaw 50-368, Poland.
| | | | - Jedrzej Grzegrzolka
- Department of Human Morphology and Embryology, Wroclaw Medical University, Wroclaw 50-368, Poland.
| | | | - Piotr Dziegiel
- Department of Human Morphology and Embryology, Wroclaw Medical University, Wroclaw 50-368, Poland.
- Department of Physiotherapy, Wroclaw University School of Physical Education, Wroclaw 51-612, Poland.
| | - Katarzyna Nowinska
- Department of Human Morphology and Embryology, Wroclaw Medical University, Wroclaw 50-368, Poland.
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15
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Menon SS, Guruvayoorappan C, Sakthivel KM, Rasmi RR. Ki-67 protein as a tumour proliferation marker. Clin Chim Acta 2019; 491:39-45. [PMID: 30653951 DOI: 10.1016/j.cca.2019.01.011] [Citation(s) in RCA: 204] [Impact Index Per Article: 40.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Revised: 01/11/2019] [Accepted: 01/11/2019] [Indexed: 12/21/2022]
Abstract
Newer treatment strategy based on proliferative nuclear marker Ki-67 targeted therapy holds promise for prioritized/personalized treatment options with regard to improved survival and outcome in patients with renal cancer. Over the past decade, the importance of Ki-67 in prognosis of breast cancer has been widely studied, however very few studies and literatures are available in the context of renal cancer which has an increasing incidence internationally. The focus of this present review is to fill the gaps pertaining to its prognosis and management with newly understood mechanisms of targeted interventions. Recent breakthrough discoveries have highlighted the correlation of Ki-67 expression to stage and metastatic potential in renal tumours. A better understanding of molecular structure and different protein domains along with its regulation will provide evidence for precise target thereby controlling the proliferation rate correlated with decrease in the Ki-67 protein levels. Therapies targeting Ki-67 is still in the preclinical stage, besides its diagnostic and/or prognostic significance, a better understanding of targeted strategical studies is required for extrapolation to the clinical use. Current understanding of the associated molecular pathways and the precise role of Ki-67 could streamline the basis for predicting renal cancer outcome.
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Affiliation(s)
- Sunil Sankunny Menon
- Department of Pediatric Surgery, SAT, Medical College, Thiruvananthapuram 695 011, Kerala, India
| | - Chandrasekharan Guruvayoorappan
- Laboratory of Immunopharmacology and Experimental Therapeutics, Division of Cancer Research, Regional Cancer Centre, Thiruvananthapuram 695 011, Kerala, India
| | - Kunnathur Murugesan Sakthivel
- Department of Biochemistry, PSG College of Arts and Science, Civil Aerodrome Post, Coimbatore 641 014, Tamil Nadu, India
| | - Rajan Radha Rasmi
- Department of Biotechnology, PSG College of Arts and Science, Civil Aerodrome Post, Coimbatore 641 014, Tamil Nadu, India.
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16
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Scholzen T, Gerlach C, Cattoretti G. An insider's view on how Ki-67, the bright beacon of cell proliferation, became very popular. A tribute to Johannes Gerdes (1950-2016). Histopathology 2018. [DOI: 10.1111/his.13511] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Thomas Scholzen
- Research Center Borstel; Leibniz Lung Center; Borstel Germany
| | | | - Giorgio Cattoretti
- Pathology; Department of Medicine and Surgery; Università di Milano-Bicocca; Monza Italy
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17
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Ki-67: more than a proliferation marker. Chromosoma 2018; 127:175-186. [PMID: 29322240 DOI: 10.1007/s00412-018-0659-8] [Citation(s) in RCA: 455] [Impact Index Per Article: 75.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 01/01/2018] [Accepted: 01/02/2018] [Indexed: 12/17/2022]
Abstract
Ki-67 protein has been widely used as a proliferation marker for human tumor cells for decades. In recent studies, multiple molecular functions of this large protein have become better understood. Ki-67 has roles in both interphase and mitotic cells, and its cellular distribution dramatically changes during cell cycle progression. These localizations correlate with distinct functions. For example, during interphase, Ki-67 is required for normal cellular distribution of heterochromatin antigens and for the nucleolar association of heterochromatin. During mitosis, Ki-67 is essential for formation of the perichromosomal layer (PCL), a ribonucleoprotein sheath coating the condensed chromosomes. In this structure, Ki-67 acts to prevent aggregation of mitotic chromosomes. Here, we present an overview of functional roles of Ki-67 across the cell cycle and also describe recent experiments that clarify its role in regulating cell cycle progression in human cells.
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18
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Evaluation of the proliferation marker Ki-67 in a large prostatectomy cohort. PLoS One 2017; 12:e0186852. [PMID: 29141018 PMCID: PMC5687762 DOI: 10.1371/journal.pone.0186852] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 10/09/2017] [Indexed: 12/01/2022] Open
Abstract
The tumor proliferation index marker Ki-67 is strongly associated with tumor cell proliferation, growth and progression, and is widely used in routine clinicopathological investigation. Prostate cancer is a complex multifaceted and biologically heterogeneous disease, and overtreatment of localized, low volume indolent tumors, is evident. Here, we aimed to assess Ki-67 expression and related outcomes of 535 patients treated with radical prostatectomy. The percentage of tumor epithelial cells expressing Ki-67 was determined by immunohistochemical assay, both digital image analysis and visual scoring by light microscope were used for quantification. The association of Ki-67 and prostate cancer was evaluated, as well as its prognostic value. There was a positive correlation between high expression of Ki-67 and Gleason score > 7 (p < 0.001) as well as tumor size (≥ 20 mm, p = 0.03). In univariate analyses, a high expression of Ki-67 in tumor epithelium was significantly associated with biochemical failure (BF) (digital scoring, p = 0.014) and (visual scoring, p = 0.004). In the multivariate analyses, a high level of Ki-67 was an independent poor prognostic factor for biochemical failure-free survival (BFFS) (Visual scoring, Ki67, p = 0.012, HR:1.50, CI95% 1.10–2.06). In conclusion, high Ki-67 expression is an independent negative prognostic marker for biochemical failure. Our findings support the role of Ki-67 as a significant, poor prognostic factor for in prostate cancer outcome.
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19
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Pavlidou T, Rosina M, Fuoco C, Gerini G, Gargioli C, Castagnoli L, Cesareni G. Regulation of myoblast differentiation by metabolic perturbations induced by metformin. PLoS One 2017; 12:e0182475. [PMID: 28859084 PMCID: PMC5578649 DOI: 10.1371/journal.pone.0182475] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 07/19/2017] [Indexed: 12/11/2022] Open
Abstract
The metabolic perturbation caused by calorie restriction enhances muscle repair by playing a critical role in regulating satellite cell availability and activity in the muscles of young and old mice. To clarify the underlying mechanisms we asked whether myoblast replication and differentiation are affected by metformin, a calorie restriction-mimicking drug. C2C12, a mouse myoblast cell line, readily differentiate in vitro and fuse to form myotubes. However, when incubated with metformin, C2C12 slow their replication and do not differentiate. Interestingly, lower doses of metformin promote myogenic differentiation. We observe that metformin treatment modulates the expression of cyclins and cyclin inhibitors thereby inducing a cell cycle perturbation that causes a delay in the G2/M transition. The effect of metformin treatment is reversible since after drug withdrawal, myoblasts can re-enter the cell cycle and/or differentiate, depending on culture conditions. Myoblasts cultured under metformin treatment fail to up-regulate MyoD and p21cip1, a key step in cell cycle exit and terminal differentiation. Although the details of the molecular mechanisms underlying the effect of the drug on myoblasts still need to be clarified, we propose that metformin negatively affects myogenic differentiation by inhibiting irreversible exit from the cell cycle through reduction of MyoD and p21cip1 levels.
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Affiliation(s)
- Theodora Pavlidou
- Laboratory of Molecular Genetics, Department of Biology, Tor Vergata University, Rome, Italy
| | - Marco Rosina
- Laboratory of Molecular Genetics, Department of Biology, Tor Vergata University, Rome, Italy
| | - Claudia Fuoco
- Laboratory of Molecular Genetics, Department of Biology, Tor Vergata University, Rome, Italy
| | - Giulia Gerini
- Laboratory of Molecular Genetics, Department of Biology, Tor Vergata University, Rome, Italy
| | - Cesare Gargioli
- Laboratory of Molecular Genetics, Department of Biology, Tor Vergata University, Rome, Italy
- * E-mail: (LC); (GC); (CG)
| | - Luisa Castagnoli
- Laboratory of Molecular Genetics, Department of Biology, Tor Vergata University, Rome, Italy
- * E-mail: (LC); (GC); (CG)
| | - Gianni Cesareni
- Laboratory of Molecular Genetics, Department of Biology, Tor Vergata University, Rome, Italy
- IRCCS, Fondazione Santa Lucia, Rome, Italy
- * E-mail: (LC); (GC); (CG)
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20
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Booth DG, Earnshaw WC. Ki-67 and the Chromosome Periphery Compartment in Mitosis. Trends Cell Biol 2017; 27:906-916. [PMID: 28838621 DOI: 10.1016/j.tcb.2017.08.001] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 08/01/2017] [Accepted: 08/02/2017] [Indexed: 12/12/2022]
Abstract
The chromosome periphery is a complex network of proteins and RNA molecules (many derived from nucleoli) that covers the outer surface of chromosomes and whose function remains mysterious. Although it was first described over 130 years ago, technological advances and the recent discovery that Ki-67 acts as an organiser of this region have allowed the chromosome periphery to be dissected in previously unattainable detail, leading to a revival of interest in this obscure chromosomal compartment. Here, we review the most recent advances into the composition, structure and function of the chromosome periphery, discuss possible roles of Ki-67 during mitosis and consider why this structure is likely to remain the focus of ongoing attention in the future.
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Affiliation(s)
- Daniel G Booth
- Centre For Neuroregeneration, Chancellor's Building, University of Edinburgh, Edinburgh, EH16 4SB, UK.
| | - William C Earnshaw
- Wellcome Trust Centre for Cell Biology, King's Buildings, University of Edinburgh, Edinburgh, EH9 3BF, UK.
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21
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Abstract
While chromatin characteristics in interphase are widely studied, characteristics of mitotic chromatin and their inheritance through mitosis are still poorly understood. During mitosis, chromatin undergoes dramatic changes: transcription stalls, chromatin-binding factors leave the chromatin, histone modifications change and chromatin becomes highly condensed. Many key insights into mitotic chromosome state and conformation have come from extensive microscopy studies over the last century. Over the last decade, the development of 3C-based techniques has enabled the study of higher order chromosome organization during mitosis in a genome-wide manner. During mitosis, chromosomes lose their cell type-specific and locus-dependent chromatin organization that characterizes interphase chromatin and fold into randomly positioned loop arrays. Upon exit of mitosis, cells are capable of quickly rearranging the chromosome conformation to form the cell type-specific interphase organization again. The information that enables this rearrangement after mitotic exit is thought to be encoded at least in part in mitotic bookmarks, e.g. histone modifications and variants, histone remodelers, chromatin factors, and non-coding RNA. Here we give an overview of the chromosomal organization and epigenetic characteristics of interphase and mitotic chromatin in vertebrates. Second, we describe different ways in which mitotic bookmarking enables epigenetic memory of the features of interphase chromatin through mitosis. And third, we explore the role of epigenetic modifications and mitotic bookmarking in cell differentiation.
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Affiliation(s)
- Marlies E. Oomen
- Program in Systems Biology, Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA, 01605-0103, USA
| | - Job Dekker
- Howard Hughes Medical Institute, Program in Systems Biology, Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA, 01605-0103, USA
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22
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Cidado J, Wong HY, Rosen DM, Cimino-Mathews A, Garay JP, Fessler AG, Rasheed ZA, Hicks J, Cochran RL, Croessmann S, Zabransky DJ, Mohseni M, Beaver JA, Chu D, Cravero K, Christenson ES, Medford A, Mattox A, De Marzo AM, Argani P, Chawla A, Hurley PJ, Lauring J, Park BH. Ki-67 is required for maintenance of cancer stem cells but not cell proliferation. Oncotarget 2017; 7:6281-93. [PMID: 26823390 PMCID: PMC4868756 DOI: 10.18632/oncotarget.7057] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 01/05/2016] [Indexed: 01/08/2023] Open
Abstract
Ki-67 expression is correlated with cell proliferation and is a prognostic marker for various cancers; however, its function is unknown. Here we demonstrate that genetic disruption of Ki-67 in human epithelial breast and colon cancer cells depletes the cancer stem cell niche. Ki-67 null cells had a proliferative disadvantage compared to wildtype controls in colony formation assays and displayed increased sensitivity to various chemotherapies. Ki-67 null cancer cells showed decreased and delayed tumor formation in xenograft assays, which was associated with a reduction in cancer stem cell markers. Immunohistochemical analyses of human breast cancers revealed that Ki-67 expression is maintained at equivalent or greater levels in metastatic sites of disease compared to matched primary tumors, suggesting that maintenance of Ki-67 expression is associated with metastatic/clonogenic potential. These results elucidate Ki-67's role in maintaining the cancer stem cell niche, which has potential diagnostic and therapeutic implications for human malignancies.
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Affiliation(s)
- Justin Cidado
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Present address: Oncology iMED, AstraZeneca, Waltham, MA, USA
| | - Hong Yuen Wong
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - D Marc Rosen
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ashley Cimino-Mathews
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Joseph P Garay
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Abigail G Fessler
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Zeshaan A Rasheed
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jessica Hicks
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Rory L Cochran
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Sarah Croessmann
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Daniel J Zabransky
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Morassa Mohseni
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Present address: Roche Sequencing, San Jose, CA, USA
| | - Julia A Beaver
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - David Chu
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Karen Cravero
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Eric S Christenson
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Arielle Medford
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Austin Mattox
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Angelo M De Marzo
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Pedram Argani
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ajay Chawla
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA, USA.,Departments of Physiology and Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Paula J Hurley
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Josh Lauring
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ben Ho Park
- The Sidney Kimmel Comprehensive Cancer Center, The Johns Hopkins University School of Medicine, Baltimore, MD, USA.,The Whiting School of Engineering, Department of Chemical and Biomolecular Engineering, The Johns Hopkins University, Baltimore, MD, USA
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23
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Booth DG, Beckett AJ, Molina O, Samejima I, Masumoto H, Kouprina N, Larionov V, Prior IA, Earnshaw WC. 3D-CLEM Reveals that a Major Portion of Mitotic Chromosomes Is Not Chromatin. Mol Cell 2016; 64:790-802. [PMID: 27840028 PMCID: PMC5128728 DOI: 10.1016/j.molcel.2016.10.009] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Revised: 08/24/2016] [Accepted: 10/05/2016] [Indexed: 11/20/2022]
Abstract
Recent studies have revealed the importance of Ki-67 and the chromosome periphery in chromosome structure and segregation, but little is known about this elusive chromosome compartment. Here we used correlative light and serial block-face scanning electron microscopy, which we term 3D-CLEM, to model the entire mitotic chromosome complement at ultra-structural resolution. Prophase chromosomes exhibit a highly irregular surface appearance with a volume smaller than metaphase chromosomes. This may be because of the absence of the periphery, which associates with chromosomes only after nucleolar disassembly later in prophase. Indeed, the nucleolar volume almost entirely accounts for the extra volume found in metaphase chromosomes. Analysis of wild-type and Ki-67-depleted chromosomes reveals that the periphery comprises 30%–47% of the entire chromosome volume and more than 33% of the protein mass of isolated mitotic chromosomes determined by quantitative proteomics. Thus, chromatin makes up a surprisingly small percentage of the total mass of metaphase chromosomes. 3D-CLEM combines light and serial block-face scanning electron microscopy The complete architecture of all 46 human chromosomes has been defined A large portion of mitotic chromosomes is not composed of chromatin Chromosome volumes determined by light and electron microscopy differ dramatically
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Affiliation(s)
- Daniel G Booth
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, EH9 3BF Edinburgh, UK.
| | - Alison J Beckett
- Biomedical Electron Microscopy Unit, Division of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Crown Street, L69 3BX Liverpool, UK
| | - Oscar Molina
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, EH9 3BF Edinburgh, UK
| | - Itaru Samejima
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, EH9 3BF Edinburgh, UK
| | - Hiroshi Masumoto
- Department of Frontier Research, Laboratory of Cell Engineering, Kazusa DNA Research Institute, Kisarazu, 292-0818 Chiba, Japan
| | - Natalay Kouprina
- Developmental Therapeutics Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-4264, USA
| | - Vladimir Larionov
- Developmental Therapeutics Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-4264, USA
| | - Ian A Prior
- Biomedical Electron Microscopy Unit, Division of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Crown Street, L69 3BX Liverpool, UK
| | - William C Earnshaw
- Wellcome Trust Centre for Cell Biology, Institute of Cell Biology, University of Edinburgh, EH9 3BF Edinburgh, UK.
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24
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Takagi M, Natsume T, Kanemaki MT, Imamoto N. Perichromosomal protein Ki67 supports mitotic chromosome architecture. Genes Cells 2016; 21:1113-1124. [DOI: 10.1111/gtc.12420] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 08/12/2016] [Indexed: 01/10/2023]
Affiliation(s)
- Masatoshi Takagi
- Cellular Dynamics Laboratory; RIKEN; 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Toyoaki Natsume
- Division of Molecular Cell Engineering; National Institute of Genetics, ROIS; and Department of Genetics, SOKENDAI; Yata 1111 Mishima Shizuoka 411-8540 Japan
| | - Masato T. Kanemaki
- Division of Molecular Cell Engineering; National Institute of Genetics, ROIS; and Department of Genetics, SOKENDAI; Yata 1111 Mishima Shizuoka 411-8540 Japan
- PRESTO; Japan Science and Technology Agency; 4-1-8 Honcho Kawaguchi Saitama 332-0012 Japan
| | - Naoko Imamoto
- Cellular Dynamics Laboratory; RIKEN; 2-1 Hirosawa Wako Saitama 351-0198 Japan
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25
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Caglayan Sozmen S, Karaman M, Cilaker Micili S, Isik S, Arikan Ayyildiz Z, Bagriyanik A, Uzuner N, Karaman O. Resveratrol ameliorates 2,4-dinitrofluorobenzene-induced atopic dermatitis-like lesions through effects on the epithelium. PeerJ 2016; 4:e1889. [PMID: 27069818 PMCID: PMC4824908 DOI: 10.7717/peerj.1889] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 03/13/2016] [Indexed: 01/03/2023] Open
Abstract
Background. Resveratrol is a natural polyphenol that exhibits anti-inflammatory effects. The aim of this study was to investigate the effects of resveratrol treatment on epithelium-derived cytokines and epithelial apoptosis in a murine model of atopic dermatitis-like lesions. Material and Methods. Atopic dermatitis-like lesions were induced in BALB/c mice by repeated application of 2,4-dinitrofluorobenzene to shaved dorsal skin. Twenty-one BALB/c mice were divided into three groups: group I (control), group II (vehicle control), and group III (resveratrol). Systemic resveratrol (30 mg/kg/day) was administered repeatedly during the 6th week of the experiment. After the mice had been sacrificed, skin tissues were examined histologically for epithelial thickness. Epithelial apoptosis (caspase-3) and epithelium-derived cytokines [interleukin (IL)-25, IL-33, and thymic stromal lymphopoietin (TSLP)] were evaluated immunohistochemically. Results. Epithelial thickness and the numbers of IL-25, IL-33, TSLP and caspase-3-positive cells were significantly higher in group II compared to group I mice. There was significant improvement in epithelial thickness in group III compared with group II mice (p < 0.05). The numbers of IL-25, IL-33, and TSLP-positive cells in the epithelium were lower in group III than in group II mice (p < 0.05). The number of caspase-3-positive cells, as an indicator of apoptosis, in the epithelium was significantly lower in group III than in group II mice (p < 0.05). Conclusion. Treatment with resveratrol was effective at ameliorating histological changes and inflammation by acting on epithelium-derived cytokines and epithelial apoptosis.
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Affiliation(s)
- Sule Caglayan Sozmen
- Faculty of Medicine, Department of Pediatric Allergy and Immunology, Dokuz Eylül University , Izmir , Turkey
| | - Meral Karaman
- Faculty of Medicine, Department of Microbiology, Dokuz Eylül University , Izmir , Turkey
| | - Serap Cilaker Micili
- Faculty of Medicine, Department of Histology and Embryology, Dokuz Eylül University , Izmir , Turkey
| | - Sakine Isik
- Faculty of Medicine, Department of Pediatric Allergy and Immunology, Dokuz Eylül University , Izmir , Turkey
| | - Zeynep Arikan Ayyildiz
- Faculty of Medicine, Department of Pediatric Allergy and Immunology, Dokuz Eylül University , Izmir , Turkey
| | - Alper Bagriyanik
- Faculty of Medicine, Department of Histology and Embryology, Dokuz Eylül University , Izmir , Turkey
| | - Nevin Uzuner
- Faculty of Medicine, Department of Pediatric Allergy and Immunology, Dokuz Eylül University , Izmir , Turkey
| | - Ozkan Karaman
- Faculty of Medicine, Department of Pediatric Allergy and Immunology, Dokuz Eylül University , Izmir , Turkey
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26
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Vuichoud C, Klap J, Loughlin KR. The Emerging Role and Promise of Biomarkers in Penile Cancer. Urol Clin North Am 2016; 43:135-43. [PMID: 26614036 DOI: 10.1016/j.ucl.2015.08.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Penile cancer is a rare malignancy, which can be a source of devastating psychosexual distress because of its implication on sexual function and self-image. Current penile staging relies on invasive techniques and is often inaccurate. The authors review the promising biomarkers currently under investigation and their application to the staging and prognosis of penile cancer. Further development of such biomarkers provides the potential of improved clinical management of this disease.
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Affiliation(s)
- Camille Vuichoud
- Division of Urology, Brigham and Women's Hospital, Harvard Medical School, 45 Francis Street, Boston, MA 02115, USA
| | - Julia Klap
- Division of Urology, Brigham and Women's Hospital, Harvard Medical School, 45 Francis Street, Boston, MA 02115, USA
| | - Kevin R Loughlin
- Division of Urology, Brigham and Women's Hospital, Harvard Medical School, 45 Francis Street, Boston, MA 02115, USA.
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27
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Sobecki M, Mrouj K, Camasses A, Parisis N, Nicolas E, Llères D, Gerbe F, Prieto S, Krasinska L, David A, Eguren M, Birling MC, Urbach S, Hem S, Déjardin J, Malumbres M, Jay P, Dulic V, Lafontaine DL, Feil R, Fisher D. The cell proliferation antigen Ki-67 organises heterochromatin. eLife 2016; 5:e13722. [PMID: 26949251 PMCID: PMC4841783 DOI: 10.7554/elife.13722] [Citation(s) in RCA: 200] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 03/06/2016] [Indexed: 12/29/2022] Open
Abstract
Antigen Ki-67 is a nuclear protein expressed in proliferating mammalian cells. It is widely used in cancer histopathology but its functions remain unclear. Here, we show that Ki-67 controls heterochromatin organisation. Altering Ki-67 expression levels did not significantly affect cell proliferation in vivo. Ki-67 mutant mice developed normally and cells lacking Ki-67 proliferated efficiently. Conversely, upregulation of Ki-67 expression in differentiated tissues did not prevent cell cycle arrest. Ki-67 interactors included proteins involved in nucleolar processes and chromatin regulators. Ki-67 depletion disrupted nucleologenesis but did not inhibit pre-rRNA processing. In contrast, it altered gene expression. Ki-67 silencing also had wide-ranging effects on chromatin organisation, disrupting heterochromatin compaction and long-range genomic interactions. Trimethylation of histone H3K9 and H4K20 was relocalised within the nucleus. Finally, overexpression of human or Xenopus Ki-67 induced ectopic heterochromatin formation. Altogether, our results suggest that Ki-67 expression in proliferating cells spatially organises heterochromatin, thereby controlling gene expression. DOI:http://dx.doi.org/10.7554/eLife.13722.001 Living cells divide in two to produce new cells. In mammals, cell division is strictly controlled so that only certain groups of cells in the body are actively dividing at any time. However, some cells may escape these controls so that they divide rapidly and form tumors. A protein called Ki-67 is only produced in actively dividing cells, where it is located in the nucleus – the structure that contains most of the cell’s DNA. Researchers often use Ki-67 as a marker to identify which cells are actively dividing in tissue samples from cancer patients, and previous studies indicated that Ki-67 is needed for cells to divide. However, the exact role of this protein was not clear. Before cells can divide they need to make large amounts of new proteins using molecular machines called ribosomes and it has been suggested that Ki-67 helps to produce ribosomes. Now, Sobecki et al. used genetic techniques to study the role of Ki-67 in mice. The experiments show that Ki-67 is not required for cells to divide in the laboratory or to make ribosomes. Instead, Ki-67 alters the way that DNA is packaged in the nucleus. Loss of Ki-67 from mice cells resulted in DNA becoming less compact, which in turn altered the activity of genes in those cells. Sobecki et al. also identified many other proteins that interact with Ki-67, so the next step following on from this research is to understand how Ki-67 alters DNA packaging at the molecular level. Another future challenge will be to find out if inhibiting the activity of Ki-67 can hinder the growth of cancer cells. DOI:http://dx.doi.org/10.7554/eLife.13722.002
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Affiliation(s)
- Michal Sobecki
- Montpellier Institute of Molecular Genetics (IGMM) CNRS UMR 5535, Centre National de la Recherche Scientifique (CNRS), Montpellier, France.,Faculty of Sciences, University of Montpellier, Montpellier, France
| | - Karim Mrouj
- Montpellier Institute of Molecular Genetics (IGMM) CNRS UMR 5535, Centre National de la Recherche Scientifique (CNRS), Montpellier, France.,Faculty of Sciences, University of Montpellier, Montpellier, France
| | - Alain Camasses
- Montpellier Institute of Molecular Genetics (IGMM) CNRS UMR 5535, Centre National de la Recherche Scientifique (CNRS), Montpellier, France.,Faculty of Sciences, University of Montpellier, Montpellier, France
| | - Nikolaos Parisis
- Montpellier Institute of Molecular Genetics (IGMM) CNRS UMR 5535, Centre National de la Recherche Scientifique (CNRS), Montpellier, France.,Faculty of Sciences, University of Montpellier, Montpellier, France
| | - Emilien Nicolas
- RNA Molecular Biology, Center for Microscopy and Molecular Imaging, Fonds de la Recherche Nationale, Université Libre de Bruxelles, Charleroi-Gosselies, Belgium
| | - David Llères
- Montpellier Institute of Molecular Genetics (IGMM) CNRS UMR 5535, Centre National de la Recherche Scientifique (CNRS), Montpellier, France.,Faculty of Sciences, University of Montpellier, Montpellier, France
| | - François Gerbe
- Faculty of Sciences, University of Montpellier, Montpellier, France.,Institute of Functional Genomics (IGF), CNRS UMR 5203, Centre National de la Recherche Scientifique (CNRS), Montpellier, France.,U1191, Inserm, Montpellier, France
| | - Susana Prieto
- Montpellier Institute of Molecular Genetics (IGMM) CNRS UMR 5535, Centre National de la Recherche Scientifique (CNRS), Montpellier, France.,Faculty of Sciences, University of Montpellier, Montpellier, France
| | - Liliana Krasinska
- Montpellier Institute of Molecular Genetics (IGMM) CNRS UMR 5535, Centre National de la Recherche Scientifique (CNRS), Montpellier, France.,Faculty of Sciences, University of Montpellier, Montpellier, France
| | - Alexandre David
- Faculty of Sciences, University of Montpellier, Montpellier, France.,Institute of Functional Genomics (IGF), CNRS UMR 5203, Centre National de la Recherche Scientifique (CNRS), Montpellier, France.,U1191, Inserm, Montpellier, France
| | - Manuel Eguren
- Spanish National Cancer Research Centre, Madrid, Spain
| | | | - Serge Urbach
- Faculty of Sciences, University of Montpellier, Montpellier, France.,Institute of Functional Genomics (IGF), CNRS UMR 5203, Centre National de la Recherche Scientifique (CNRS), Montpellier, France.,U1191, Inserm, Montpellier, France.,Functional Proteomics Platform, Institute of Functional Genomics, Montpellier, France
| | - Sonia Hem
- Mass Spectrometry Platform MSPP, SupAgro, Montpellier, France
| | - Jérôme Déjardin
- Faculty of Sciences, University of Montpellier, Montpellier, France.,Institute of Human Genetics (IGH) CNRS UPR 1142, Centre National de la Recherche Scientifique, Montpellier, France
| | | | - Philippe Jay
- Faculty of Sciences, University of Montpellier, Montpellier, France.,Institute of Functional Genomics (IGF), CNRS UMR 5203, Centre National de la Recherche Scientifique (CNRS), Montpellier, France.,U1191, Inserm, Montpellier, France
| | - Vjekoslav Dulic
- Montpellier Institute of Molecular Genetics (IGMM) CNRS UMR 5535, Centre National de la Recherche Scientifique (CNRS), Montpellier, France.,Faculty of Sciences, University of Montpellier, Montpellier, France
| | - Denis Lj Lafontaine
- RNA Molecular Biology, Center for Microscopy and Molecular Imaging, Fonds de la Recherche Nationale, Université Libre de Bruxelles, Charleroi-Gosselies, Belgium
| | - Robert Feil
- Montpellier Institute of Molecular Genetics (IGMM) CNRS UMR 5535, Centre National de la Recherche Scientifique (CNRS), Montpellier, France.,Faculty of Sciences, University of Montpellier, Montpellier, France
| | - Daniel Fisher
- Montpellier Institute of Molecular Genetics (IGMM) CNRS UMR 5535, Centre National de la Recherche Scientifique (CNRS), Montpellier, France.,Faculty of Sciences, University of Montpellier, Montpellier, France
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28
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Lee YH, Liu X, Qiu F, O’Connor TR, Yen Y, Ann DK. HP1β is a biomarker for breast cancer prognosis and PARP inhibitor therapy. PLoS One 2015; 10:e0121207. [PMID: 25769025 PMCID: PMC4358987 DOI: 10.1371/journal.pone.0121207] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 01/28/2015] [Indexed: 11/23/2022] Open
Abstract
Members of the heterochromatin protein 1 family (HP1α, β and γ) are mostly associated with heterochromatin and play important roles in gene regulation and DNA damage response. Altered expression of individual HP1 subtype has profound impacts on cell proliferation and tumorigenesis. We analyzed the expression profile of HP1 family by data mining using a published microarray data set coupled with retrospective immunohistochemistry analyses of archived breast cancer biospecimens. We found that the patient group overexpressing HP1β mRNA is associated with poorly differentiated breast tumors and with a significantly lower survival rate. Immunohistochemical staining against HP1α, HP1β and HP1γ shows that respective HP1 expression level is frequently altered in breast cancers. 57.4 - 60.1% of samples examined showed high HP1β expression and 39.9 - 42.6 % of examined tumors showed no or low expression of each HP1 subtype. Interestingly, comparative analysis on HP1 expression profile and breast cancer markers revealed a positive correlation between the respective expression level of all three HP1 subtypes and Ki-67, a cell proliferation and well-known breast cancer marker. To explore the effect of individual HP1 on PARP inhibitor therapy for breast cancer, MCF7 breast cancer cells and individually HP1-depleted MCF7 cells were treated with PARP inhibitor ABT-888 with or without carboplatin. Notably, HP1β-knockdown cells are hypersensitive to the PARP inhibitor ABT-888 alone and its combination with carboplatin. In summary, while increased HP1β expression is associated with the poor prognosis in breast cancer, compromised HP1β abundance may serve as a useful predictive marker for chemotherapy, including PARP inhibitors against breast cancer.
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Affiliation(s)
- Young-Ho Lee
- Department of Molecular Pharmacology, Beckman Research Institute, City of Hope, Duarte, California, United States of America
- * E-mail: (YL); (DA)
| | - Xiyong Liu
- Department of Molecular Pharmacology, Beckman Research Institute, City of Hope, Duarte, California, United States of America
| | - Fuming Qiu
- Department of Medical Oncology, Second Affiliated Hospital, Zhejiang University, School of Medicine, Hangzhou, China
| | - Timothy R. O’Connor
- Department of Cancer Biology, Beckman Research Institute, City of Hope, Duarte, California, United States of America
| | - Yun Yen
- Department of Molecular Pharmacology, Beckman Research Institute, City of Hope, Duarte, California, United States of America
| | - David K. Ann
- Department of Molecular Pharmacology, Beckman Research Institute, City of Hope, Duarte, California, United States of America
- * E-mail: (YL); (DA)
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29
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Abstract
Classification of lung neuroendocrine (NE) tumors is a step-wise process with four tumor categories being identified by morphology, namely typical carcinoid (TC), atypical carcinoid, large-cell NE carcinoma, and small-cell lung carcinoma (SCLC). Ki-67 antigen or protein (henceforth simply Ki-67) has been largely studied in these tumors, but the clinical implications are so far not clear. A well-defined role has regarded the diagnostic use in the separation of TC and AC from SCLC in nonsurgical specimens, with monoclonal antibody MIB-1 resulting in the most used reagent after antigen retrieval procedures. Uncertainties, however, have arisen in its assessment, usually expressed as Ki-67 labeling index, because of some variability in obtaining either value of the fraction. A diagnostic role is currently lacking, even though there are significant differences in most cases between TC and AC, less so between large-cell NE carcinoma and SCLC. In addition, the prognostic role of Ki-67 is debated, likely due to methodological and biological reasons. The last challenge would be to identify an effective lung-specific grading system based on Ki-67 labeling index. In this review article, five relevant issues to Ki-67 have been addressed by using a question-answer methodology, with relevant key points discussing major interpretation issues. The conclusion is that Ki-67 is a feasible and potentially meaningful marker in lung NE tumors, but more data are needed to determine its ideal function in this setting of tumors.
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30
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Takagi M, Nishiyama Y, Taguchi A, Imamoto N. Ki67 antigen contributes to the timely accumulation of protein phosphatase 1γ on anaphase chromosomes. J Biol Chem 2014; 289:22877-22887. [PMID: 25012651 DOI: 10.1074/jbc.m114.556647] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Ki67 is a protein widely used as cell-proliferation marker, with its cellular functions being hardly unveiled. In this paper, we present the direct interaction between Ki67 and PP1γ, a protein phosphatase showing characteristic accumulation on anaphase chromosomes via the canonical PP1-binding motif within Ki67. In cells depleted of Ki67, PP1γ is targeted to anaphase chromosomes less efficiently. Additionally, overexpression of Ki67, but not a mutant form without the ability to bind PP1γ, induced ectopic localization of PP1γ οn metaphase chromosomes. These observations demonstrate that Ki67 is one factor that defines the cellular behavior of PP1γ in anaphase. To explore the specific roles of the subset of PP1γ recruited on chromosome via its interaction with Ki67 (PP1γ-Ki67), endogenous Ki67 was replaced with a Ki67 mutant deficient in its ability to interact with PP1γ. Although no obvious defects in the progression of mitosis were observed, the timing of dephosphorylation of the mutant Ki67 in anaphase was delayed, indicating that Ki67 itself is one of the substrates of PP1γ-Ki67.
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Affiliation(s)
- Masatoshi Takagi
- Cellular Dynamics Laboratory, RIKEN, 2-1, Hirosawa, Wako, Saitama 351-0198, Japan.
| | - Yuko Nishiyama
- Cellular Dynamics Laboratory, RIKEN, 2-1, Hirosawa, Wako, Saitama 351-0198, Japan
| | - Atsuko Taguchi
- Cellular Dynamics Laboratory, RIKEN, 2-1, Hirosawa, Wako, Saitama 351-0198, Japan
| | - Naoko Imamoto
- Cellular Dynamics Laboratory, RIKEN, 2-1, Hirosawa, Wako, Saitama 351-0198, Japan.
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31
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Zhou J, Bi H, Zhan P, Chang C, Xu C, Huang X, Yu L, Yao X, Yan J. Overexpression of HP1γ is associated with poor prognosis in non-small cell lung cancer cell through promoting cell survival. Tumour Biol 2014; 35:9777-85. [PMID: 24981246 DOI: 10.1007/s13277-014-2182-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2014] [Accepted: 06/02/2014] [Indexed: 11/28/2022] Open
Abstract
Heterochromatin protein 1γ (HP1γ), which binds to di- or trimethylated lysine 9 on histone H3 (H3K9), plays an important role in chromatin packaging and gene transcriptional regulation. Recently, HP1γ has been implicated in cancer development. However, its clinical relevance and functional role in non-small cell lung cancer (NSCLC) remain elusive. In this study, we found that HP1γ expression was elevated in NSCLC samples at the messenger RNA (mRNA) level compared to adjacent normal lung tissues. In a cohort of 108 NSCLC patients, HP1γ overexpression is significantly associated with N stage (P = 0.003), pathological tumor-node-metastasis (TNM) stage (P = 0.013), smoking status (P = 0.009), and gender (P = 0.042). Patients with a high level of HP1γ expression showed a poorer overall survival rate than those with low HP1γ expression (P = 0.017). Multivariate analysis revealed that HP1γ expression is an independent prognostic marker. We also found knockdown of HP1γ in A549 and NCI-H1975 cells induced apoptosis accompanied with suppressed cell proliferation and colony formation. Consistently, pro-apoptotic proteins, Bax and GADD45α, were upregulated in response to HP1γ depletion. Altogether, our data suggested that HP1γ plays an important role in promoting NSCLC and may represent a novel prognostic biomarker and therapeutic target for the disease.
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Affiliation(s)
- Ji Zhou
- Department of Respiratory Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, 210029, Jiangsu, China
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32
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Booth DG, Takagi M, Sanchez-Pulido L, Petfalski E, Vargiu G, Samejima K, Imamoto N, Ponting CP, Tollervey D, Earnshaw WC, Vagnarelli P. Ki-67 is a PP1-interacting protein that organises the mitotic chromosome periphery. eLife 2014; 3:e01641. [PMID: 24867636 PMCID: PMC4032110 DOI: 10.7554/elife.01641] [Citation(s) in RCA: 127] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2013] [Accepted: 04/27/2014] [Indexed: 12/23/2022] Open
Abstract
When the nucleolus disassembles during open mitosis, many nucleolar proteins and RNAs associate with chromosomes, establishing a perichromosomal compartment coating the chromosome periphery. At present nothing is known about the function of this poorly characterised compartment. In this study, we report that the nucleolar protein Ki-67 is required for the assembly of the perichromosomal compartment in human cells. Ki-67 is a cell-cycle regulated protein phosphatase 1-binding protein that is involved in phospho-regulation of the nucleolar protein B23/nucleophosmin. Following siRNA depletion of Ki-67, NIFK, B23, nucleolin, and four novel chromosome periphery proteins all fail to associate with the periphery of human chromosomes. Correlative light and electron microscopy (CLEM) images suggest a near-complete loss of the entire perichromosomal compartment. Mitotic chromosome condensation and intrinsic structure appear normal in the absence of the perichromosomal compartment but significant differences in nucleolar reassembly and nuclear organisation are observed in post-mitotic cells.DOI: http://dx.doi.org/10.7554/eLife.01641.001.
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Affiliation(s)
- Daniel G Booth
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
| | - Masatoshi Takagi
- Cellular Dynamics Laboratory, Riken Advanced Science Institute, Wako Saitama, Japan
| | - Luis Sanchez-Pulido
- MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Elizabeth Petfalski
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
| | - Giulia Vargiu
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
| | - Kumiko Samejima
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
| | - Naoko Imamoto
- Cellular Dynamics Laboratory, Riken Advanced Science Institute, Wako Saitama, Japan
| | - Chris P Ponting
- MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - David Tollervey
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
| | - William C Earnshaw
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, Edinburgh, United Kingdom
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33
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Antibody selection for immunocytochemical characterization of the male reproductive system in Psittaciformes. Theriogenology 2013; 80:597-608. [PMID: 23910890 DOI: 10.1016/j.theriogenology.2013.05.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Revised: 05/28/2013] [Accepted: 05/29/2013] [Indexed: 11/24/2022]
Abstract
The success of breeding programs is limited by the sparse knowledge about endocrine regulation and biochemical reactions in the psittacine male tract. The immunocytochemical analysis of parrots' testicular tissues provides an insight into their reproductive system but is often hampered by the lack of reliable antibodies. In the present study, we tested a large panel of antibodies raised against steroid receptors, steroidogenic enzymes, relaxin peptides including their receptors, and proliferation markers on paraffin sections of testicular tissue from eight psittacine genera representing three continents. All investigated species displayed the tested markers in somatic and germ cells of testis and epididymis, even though cell distribution was partly heterogenous and in species-specific patterns. The 17β-hydroxysteroid-dehydrogenase-2, 3β-hydroxysteroid-dehydrogenase, and smooth muscle actin allowed the cross-species differentiation between active and nonactive gonads. The remaining steroidogenic enzymes, steroid receptors, relaxin peptides, and Ki67 proved to be suitable to define reproductive activity depending on the parrot species. Adapting immunocytochemical methods to different psittacines was successful, though various cellular expression patterns do not allow the transfer of results among different parrot species. However, the availability of a reliable repertory of sexual markers is important to examine reproductive biology of psittacine birds.
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Slezak J, Truong M, Huang W, Jarrard D. HP1γ expression is elevated in prostate cancer and is superior to Gleason score as a predictor of biochemical recurrence after radical prostatectomy. BMC Cancer 2013; 13:148. [PMID: 23522301 PMCID: PMC3618256 DOI: 10.1186/1471-2407-13-148] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Accepted: 03/18/2013] [Indexed: 12/05/2022] Open
Abstract
Background Aberrant chromatin structure in cancer cells results from altered proteins involved in its packaging. Heterochromatin protein 1 gamma (HP1γ) is a non-histone heterochromatic protein that functions to maintain chromatin stability and is important in embryonic development. Given an interest in the role developmental genes play in cancer, we investigated HP1γ expression in prostate cancer (PCa) and its prognostic associations. Methods Tissue microarrays consisting of benign (N = 96), localized cancer (N = 146), metastatic PCa (N = 44), and HGPIN (N = 50) were immunoflourescently stained for HP1γ and Ki-67. Using a novel, automated quantitative imaging system, VECTRA™, epithelial staining in both the nucleus and cytoplasm was quantified and compared against clinicopathologic variables. Results HP1γ is significantly elevated in HGPIN (80%), localized PCa (76%), and metastatic PCa (98%) compared to benign tissues from both the nuclear and cytoplasmic compartments (P < 0.0001). Increased nuclear and total HP1γ expression was associated with Gleason score (P = 0.02 and P = 0.04 respectively). Given known binding to the C-terminus of Ki-67, a co-expression analysis was performed that revealed a correlation between nuclear and cytoplasmic HP1γ and Ki-67 (Pearson Coefficient 0.321 and 0.562 respectively, P < 0.0001). Cox survival analysis demonstrated that cytoplasmic HP1γ expression was an independent prognostic marker and out-performed pathological Gleason score for predicting PSA-recurrence after radical prostatectomy. Conclusions In this first detailed analysis of HP1γ expression in cancer, VECTRA™ demonstrates compartmentalized and total HP1γ protein expression is increased in PCa and that expression correlates with clinical outcomes better than Gleason score. Given the critical role HP1γ plays in chromatin organization and gene expression, it represents a novel prognostic and therapeutic target.
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Affiliation(s)
- Jon Slezak
- School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI 53750, USA
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Pacal M, Bremner R. Mapping differentiation kinetics in the mouse retina reveals an extensive period of cell cycle protein expression in post-mitotic newborn neurons. Dev Dyn 2012; 241:1525-44. [PMID: 22837015 DOI: 10.1002/dvdy.23840] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/18/2012] [Indexed: 01/16/2023] Open
Abstract
BACKGROUND Knowledge of gene expression kinetics around neuronal cell birth is required to dissect mechanisms underlying progenitor fate. Here, we timed cell cycle and neuronal protein silencing/induction during cell birth in the developing murine retina. RESULTS The pan-cell cycle markers Pcna and Mcm6 were present in the post-mitotic ganglion cell layer. Although confined to the neuroblastic layer (NBL), 6-7% of Ki67(+) cells lacked six progenitor/cell cycle markers, and expressed neuronal markers. To define protein extinction/induction timing, we defined G2/M length throughout retinogenesis, which was typically 1-2 h, but <10% cells took double this time. BrdU-chase analyses revealed that at E12.5, Tubb3 (Tuj1) appeared at M-phase, followed by Calb2 and Dcx at ~2 h, Elavl2/3/4 at ~4 h, and Map2 at ~6 h after cell birth, and these times extended with embryonic age. Strikingly, Ki67 was not extinguished until up to a day after cell cycle exit, coinciding with exit from the NBL and induction of late markers such as Map1b/Uchl1/Rbfox3. CONCLUSIONS A minor population of progenitors transits slowly through G2/M and, most importantly, some cell cycle proteins are retained for an unexpectedly long period in post-mitotic neurons. The high-resolution map of cell birth kinetics reported here provides a framework to better define mechanisms that regulate neurogenesis.
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Affiliation(s)
- Marek Pacal
- Genetics and Development Division, Toronto Western Research Institute, University Health Network, Toronto, Canada
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Analysis of human Ki-67 gene promoter and identification of the Sp1 binding sites for Ki-67 transcription. Tumour Biol 2011; 33:257-66. [DOI: 10.1007/s13277-011-0277-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Accepted: 11/15/2011] [Indexed: 10/15/2022] Open
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Sampson HW, Chaput CD, Brannen J, Probe RA, Guleria RS, Pan J, Baker KM, VanBuren V. Alcohol induced epigenetic perturbations during the inflammatory stage of fracture healing. Exp Biol Med (Maywood) 2011; 236:1389-401. [PMID: 22087020 DOI: 10.1258/ebm.2011.011207] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
It is well recognized by orthopedic surgeons that fractures of alcoholics are more difficult to heal successfully and have a higher incidence of non-union, but the mechanism of alcohol's effect on fracture healing is unknown. In order to give direction for the study of the effects of alcohol on fracture healing, we propose to identify gene expression and microRNA changes during the early stages of fracture healing that might be attributable to alcohol consumption. As the inflammatory stage appears to be the most critical for successful fracture healing, this paper focuses on the events at day three following fracture or the stage of inflammation. Sprague-Dawley rats were placed on an ethanol-containing or pair-fed Lieber and DeCarli diet for four weeks prior to surgical fracture. Following insertion of a medullary pin, a closed mid-diaphyseal fracture was induced using a Bonnarens and Einhorn fracture device. At three days' post-fracture, the region of the fracture calluses was harvested from the right hind-limb. RNA was extracted and microarray analysis was conducted against the entire rat genome. There were 35 genes that demonstrated significant increased expression due to alcohol consumption and 20 that decreased due to alcohol. In addition, the expression of 20 microRNAs was increased and six decreased. In summary, while it is recognized that mRNA levels may or may not represent protein levels successfully produced by the cell, these studies reveal changes in gene expression that support the hypothesis that alcohol consumption affects events involved with inflammation. MicroRNAs are known to modulate mRNA and these findings were consistent with much of what was seen with mRNA microarray analysis, especially the involvement of smad4 which was demonstrated by mRNA microarray, microRNA and polymerase chain reaction.
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Affiliation(s)
- H Wayne Sampson
- Department of Systems Biology and Translational Medicine, Texas A&M Health Science Center, College of Medicine, USA.
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Reitemeier S, Hänse M, Hahn A, Schmidt V, Steinbach-Sobiraj K, Krautwald-Junghanns ME, Einspanier A. Evaluating the reproductive status of the male budgerigar (Melopsittacus undulatus). Gen Comp Endocrinol 2011; 171:350-8. [PMID: 21377466 DOI: 10.1016/j.ygcen.2011.02.028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2010] [Revised: 02/05/2011] [Accepted: 02/25/2011] [Indexed: 01/10/2023]
Abstract
Limited knowledge about male psittacine reproduction reduces the success of breeding programmes. Within the scope of fecundity assessment, classification of male sexual status is essential for effective conservation of the species. The aim of the present study was to investigate the testes of male budgerigars (Melopsittacus undulatus), as psittaciform model species to verify their reproductive status by morphological and immunocytochemical examination. Using light microscopy, gonadal samples were categorized resulting in three reproductive states (active, intermediate, non-active). Calculation of testes weights plus measurement of tubular and interstitial dimensions displayed significant (p ≤ 0.05) differences between all three reproductive stages. Lipids in the testicular tubules, analysed by Sudan black staining and fluorescence microscopy (DAPI(2) mode) were highly present in non-active status. Immunocytochemistry involved two different hydroxysteroid dehydrogenases (HSD), 3β-HSD and 17β-HSD-2, as markers for steroidogenesis, as well as steroid receptors for androgens (AR), oestrogen (ER) and progesterone (PR). Both HSDs and AR declined in non-active gonads compared to active and intermediate stages, with a positive signal in germ and somatic cells of testis and epididymis. ER and PR were detected in testicular and epididymal cells, similarly expressed in all three stages. The proliferation rate of germ cells in the testicular tubules, obtained by Ki67, differed significantly in active (38.67%), intermediate (32.40%) and non-active (6.01%) status. According to this morphological study, we have been able to establish markers for the reproductive staging of psittacine testes. This knowledge will be useful to deepen reproductive biology in budgerigars.
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Affiliation(s)
- Susanne Reitemeier
- Clinic for Birds and Reptiles, Veterinary Faculty, University of Leipzig, An den Tierkliniken 17, 04103 Leipzig, Germany.
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O'Donohue MF, Choesmel V, Faubladier M, Fichant G, Gleizes PE. Functional dichotomy of ribosomal proteins during the synthesis of mammalian 40S ribosomal subunits. ACTA ACUST UNITED AC 2010; 190:853-66. [PMID: 20819938 PMCID: PMC2935573 DOI: 10.1083/jcb.201005117] [Citation(s) in RCA: 157] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Subsets of 40S ribosomal subunits are required for initiating rRNA processing, rRNA maturation, and nuclear export. Our knowledge of the functions of metazoan ribosomal proteins in ribosome synthesis remains fragmentary. Using siRNAs, we show that knockdown of 31 of the 32 ribosomal proteins of the human 40S subunit (ribosomal protein of the small subunit [RPS]) strongly affects pre–ribosomal RNA (rRNA) processing, which often correlates with nucleolar chromatin disorganization. 16 RPSs are strictly required for initiating processing of the sequences flanking the 18S rRNA in the pre-rRNA except at the metazoan-specific early cleavage site. The remaining 16 proteins are necessary for progression of the nuclear and cytoplasmic maturation steps and for nuclear export. Distribution of these two subsets of RPSs in the 40S subunit structure argues for a tight dependence of pre-rRNA processing initiation on the folding of both the body and the head of the forming subunit. Interestingly, the functional dichotomy of RPS proteins reported in this study is correlated with the mutation frequency of RPS genes in Diamond-Blackfan anemia.
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Affiliation(s)
- Marie-Françoise O'Donohue
- Laboratoire de Biologie Moléculaire des Eucaryotes, Université de Toulouse-UPS and Centre National de La Recherche Scientifique, F-31000 Toulouse, France
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Horbinski C, Oakley GJ, Cieply K, Mantha GS, Nikiforova MN, Dacic S, Seethala RR. The prognostic value of Ki-67, p53, epidermal growth factor receptor, 1p36, 9p21, 10q23, and 17p13 in skull base chordomas. Arch Pathol Lab Med 2010; 134:1170-6. [PMID: 20670138 DOI: 10.5858/2009-0380-oa.1] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
CONTEXT Skull base chordomas are rare, locally aggressive, notochord-derived neoplasms for which prognostically relevant biomarkers are not well established. OBJECTIVE To evaluate whether newly discovered molecular alterations in chordomas have prognostic significance similar to what has been described regarding Ki-67 proliferation index. DESIGN We conducted a retrospective study of 28 cases of primary clival chordomas. RESULTS Ki-67 proliferation index 5% or more, p53 accumulation, and epidermal growth factor receptor expression were seen in 32%, 44%, and 8% of chordomas, respectively. 1p loss of heterozygosity (LOH) and/or 1p36 hemizygous deletion was seen in 30% of tumors, while 9p LOH and/or 9p21 homozygous deletion was seen in 21% of cases. Loss of heterozygosity at 10q23 and 17p13 were identified in 57% and 52% of cases, respectively. Ki-67 proliferation index 5% or more and 9p LOH were significantly associated with a shorter overall survival, while homozygous deletion at 9p21 via fluorescence in situ hybridization approached significance. No correlation with survival was found for p53 or epidermal growth factor receptor expression, 1p36 hemizygous deletion, or LOH at 1p, 10q23, or 17p13. CONCLUSIONS Chordomas with elevated Ki-67 proliferation index or deletion at 9p21 may be at risk for a more aggressive clinical course and shorter survival. These biomarkers may thus be used to improve therapeutic stratification.
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Affiliation(s)
- Craig Horbinski
- Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
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Horbinski C, Oakley GJ, Cieply K, Mantha GS, Nikiforova MN, Dacic S, Seethala RR. The prognostic value of Ki-67, p53, epidermal growth factor receptor, 1p36, 9p21, 10q23, and 17p13 in skull base chordomas. Arch Pathol Lab Med 2010. [PMID: 20670138 DOI: 10.1043/2009-0380-oa.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
CONTEXT Skull base chordomas are rare, locally aggressive, notochord-derived neoplasms for which prognostically relevant biomarkers are not well established. OBJECTIVE To evaluate whether newly discovered molecular alterations in chordomas have prognostic significance similar to what has been described regarding Ki-67 proliferation index. DESIGN We conducted a retrospective study of 28 cases of primary clival chordomas. RESULTS Ki-67 proliferation index 5% or more, p53 accumulation, and epidermal growth factor receptor expression were seen in 32%, 44%, and 8% of chordomas, respectively. 1p loss of heterozygosity (LOH) and/or 1p36 hemizygous deletion was seen in 30% of tumors, while 9p LOH and/or 9p21 homozygous deletion was seen in 21% of cases. Loss of heterozygosity at 10q23 and 17p13 were identified in 57% and 52% of cases, respectively. Ki-67 proliferation index 5% or more and 9p LOH were significantly associated with a shorter overall survival, while homozygous deletion at 9p21 via fluorescence in situ hybridization approached significance. No correlation with survival was found for p53 or epidermal growth factor receptor expression, 1p36 hemizygous deletion, or LOH at 1p, 10q23, or 17p13. CONCLUSIONS Chordomas with elevated Ki-67 proliferation index or deletion at 9p21 may be at risk for a more aggressive clinical course and shorter survival. These biomarkers may thus be used to improve therapeutic stratification.
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Affiliation(s)
- Craig Horbinski
- Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
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Abstract
Primordial germ cells (PGCs) are embryonic progenitors for the gametes. In the gastrulating mouse embryo, a small group of cells begin expressing a unique set of genes and so commit to the germline. Over the next 3-5 days, these PGCs migrate anteriorly and increase rapidly in number via mitotic division before colonizing the newly formed gonads. PGCs then express a different set of unique genes, their inherited epigenetic imprint is erased and an individual methylation imprint is established, and for female PGCs, the silent X chromosome is reactivated. At this point, germ cells (GCs) commit to either a female or male sexual lineage, denoted by meiosis entry and mitotic arrest, respectively. This developmental program is determined by cues emanating from the somatic environment.
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Affiliation(s)
- Katherine A Ewen
- Division of Molecular Genetics and Development, Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD 4072, Australia
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Brown JP, Bullwinkel J, Baron-Lühr B, Billur M, Schneider P, Winking H, Singh PB. HP1gamma function is required for male germ cell survival and spermatogenesis. Epigenetics Chromatin 2010; 3:9. [PMID: 20423503 PMCID: PMC2877046 DOI: 10.1186/1756-8935-3-9] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2009] [Accepted: 04/27/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND HP1 proteins are conserved components of eukaryotic constitutive heterochromatin. In mammals, there are three genes that encode HP1-like proteins, termed HP1alpha, HP1beta and HP1gamma, which have a high degree of homology This paper describes for the first time, to our knowledge, the physiological function of HP1gamma using a gene-targeted mouse. RESULTS While targeting the Cbx3 gene (encoding the HP1gamma protein) with a conditional targeting vector, we generated a hypomorphic allele (Cbx3hypo), which resulted in much reduced (barely detectable) levels of HP1gamma protein. Homozygotes for the hypomorphic allele (Cbx3hypo/hypo) are rare, with only 1% of Cbx3hypo/hypo animals reaching adulthood. Adult males exhibit a severe hypogonadism that is associated with a loss of germ cells, with some seminiferous tubules retaining only the supporting Sertoli cells (Sertoli cell-only phenotype). The percentage of seminiferous tubules that are positive for L1 ORF1 protein (ORF1p) in Cbx3hypo/hypo testes is greater than that for wild-type testes, indicating that L1 retrotransposon silencing is reversed, leading to ectopic expression of ORF1p in Cbx3hypo/hypo germ cells. CONCLUSIONS The Cbx3 gene product (the HP1gamma protein) has a non-redundant function during spermatogenesis that cannot be compensated for by the other two HP1 isotypes. The Cbx3hypo/hypo spermatogenesis defect is similar to that found in Miwi2 and Dnmt3L mutants. The Cbx3 gene-targeted mice generated in this study provide an appropriate model for the study of HP1gamma in transposon silencing and parental imprinting.
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Affiliation(s)
- Jeremy P Brown
- Division of Immunoepigenetics, Department of Immunology and Cell Biology, Research Center Borstel, D-23845 Borstel, Germany.
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Sheval EV, Dudnik OA, Abramchuk SS, Polyakov VY. Perichromosomal layer proteins associate with chromosome scaffold and nuclear matrix throughout the cell cycle. BIOCHEMISTRY MOSCOW SUPPLEMENT SERIES A-MEMBRANE AND CELL BIOLOGY 2009. [DOI: 10.1134/s199074780902010x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Sandhu KS. Intrinsic disorder explains diverse nuclear roles of chromatin remodeling proteins. J Mol Recognit 2009; 22:1-8. [PMID: 18802931 DOI: 10.1002/jmr.915] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Chromatin remodelers, a group of proteins involved in nucleosome re-positioning and modification, have extensive range of interacting partners. They form multimeric complexes and interact with modified histones, transcription, splicing, and replication factors, DNA, RNA, and the factors related to the maintenance of chromosome structure. Such diverse range of interactions is hard to explain with the presumed highly structured form of the protein. In the current analysis, the conformations of chromatin remodelers were explored using protein disorder prediction algorithms. The study revealed that a significant proportion (p < 2.2e-16) of these proteins harbor at least one long region of intrinsic disorder (>70 aa). These unstructured regions do not exhibit any preference to the N/C terminal or middle of the protein. They do not show any significant representation in the Protein Data Bank (PDB) structure repository. Limited examples from PDB indicate direct involvement of disordered regions in binding of chromatin remodeling proteins to naked or modified DNA, histones, and other chromatin-related factors. Furthermore, intrinsic disorder seen in these proteins correlates to the presence of low sequence complexity regions (p = 1.851e-10) particularly the tandem repeats of hydrophilic and charged amino acids. This probably hints at their evolutionary origin via repeat expansion. The disordered regions may enable these proteins to reversibly bind to various interacting partners and eventually contribute to functional diversity and specialization of chromatin remodeling complexes. These could also endow combinatorial action of multiple domains within a protein. We further discuss the prominent association of intrinsic disorder with other chromatin-related proteins and its functional relevance therein.
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Affiliation(s)
- Kuljeet Singh Sandhu
- Department of Animal Development and Genetics, Evolutionary Biology Center, Uppsala University, Norbyvagen 18A, Uppsala 75236, Sweden.
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Aucott R, Bullwinkel J, Yu Y, Shi W, Billur M, Brown JP, Menzel U, Kioussis D, Wang G, Reisert I, Weimer J, Pandita RK, Sharma GG, Pandita TK, Fundele R, Singh PB. HP1-beta is required for development of the cerebral neocortex and neuromuscular junctions. ACTA ACUST UNITED AC 2008; 183:597-606. [PMID: 19015315 PMCID: PMC2582898 DOI: 10.1083/jcb.200804041] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
HP1 proteins are thought to be modulators of chromatin organization in all mammals, yet their exact physiological function remains unknown. In a first attempt to elucidate the function of these proteins in vivo, we disrupted the murine Cbx1 gene, which encodes the HP1-β isotype, and show that the Cbx1−/−-null mutation leads to perinatal lethality. The newborn mice succumbed to acute respiratory failure, whose likely cause is the defective development of neuromuscular junctions within the endplate of the diaphragm. We also observe aberrant cerebral cortex development in Cbx1−/− mutant brains, which have reduced proliferation of neuronal precursors, widespread cell death, and edema. In vitro cultures of neurospheres from Cbx1−/− mutant brains reveal a dramatic genomic instability. Our results demonstrate that HP1 proteins are not functionally redundant and that they are likely to regulate lineage-specific changes in heterochromatin organization.
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Affiliation(s)
- Rebecca Aucott
- Division of Immunoepigenetics, Department of Immunology and Cell Biology, Research Center Borstel, Borstel, Germany
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Wang R, Luo D, Ma X, Yang W, Chen R, Liu Y, Meng L, Zhou J, Xu G, Lu YP, Wang S, Ma D. Antisense Ki-67 cDNA transfection reverses the tumorigenicity and induces apoptosis in human breast cancer cells. Cancer Invest 2008; 26:830-5. [PMID: 18798062 DOI: 10.1080/07357900801941878] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Effects of antisense Ki-67 cDNA transfection on breast cancer cells were investigated in this study. Transfection of antisense Ki-67 cDNA resulted in a 70%-80% reduction in proliferation of MDA-MB-435s, cells which highly expressed Ki-67 mRNA and protein. Transwell assay showed that mobility and invasion capability was dramatically inhibited by 50%-60%, and cell cycle analysis displayed a higher proportion in G(2)/M and G(0)/G(1) phases accompanied by remarkably increased ratio of apoptotic cells. Our results suggested that antisense Ki-67 cDNA vector treatment might be an important potential option in the anticancer therapy.
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Affiliation(s)
- Rui Wang
- Cancer Biology Research Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, P. R. China
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Smith RR, Barile L, Messina E, Marbán E. Stem cells in the heart: what's the buzz all about?--Part 1: preclinical considerations. Heart Rhythm 2008; 5:749-57. [PMID: 18452881 DOI: 10.1016/j.hrthm.2008.02.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2007] [Accepted: 02/02/2008] [Indexed: 10/22/2022]
Abstract
New approaches for cardiac repair have been enabled by the discovery that the heart contains its own reservoir of stem cells. These cells are positive for various stem/progenitor cell markers, are self-renewing, and exhibit multilineage differentiation potential. Recently we developed a method for ex vivo expansion of cardiac-derived stem cells from human myocardial biopsies with a view to subsequent autologous transplantation for myocardial regeneration. Here we review the state of the cardiac stem cell field and our own work on cardiosphere-derived stem cells from human hearts. The first of this two-part review outlines emerging preclinical data on the application of cardiac stem cells. Part 2 continues with a discussion of other stem cell sources with clinical potential, a summary of the critical issues surrounding stem cell therapy (with an emphasis on the crucial issue of how cell transplantation may influence arrhythmias), our perception of clinical stem cell trials to date, and the issues facing the clinical application of cardiac stem cells.
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Tollefson MK, Thompson RH, Sheinin Y, Lohse CM, Cheville JC, Leibovich BC, Kwon ED. Ki-67 and coagulative tumor necrosis are independent predictors of poor outcome for patients with clear cell renal cell carcinoma and not surrogates for each other. Cancer 2007; 110:783-90. [PMID: 17594714 DOI: 10.1002/cncr.22840] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND Ki-67 is a cell proliferation protein associated with aggressive clear cell renal cell carcinoma (ccRCC). A recent report suggests that Ki-67 may represent a surrogate marker for coagulative tumor necrosis. Thus, the goal was to directly test whether Ki-67 and necrosis convey similar or distinct information for the prognostic assessment of ccRCC. METHODS Tumor specimens from 741 consecutively treated patients who underwent surgery for ccRCC between 1990 and 1999 were evaluated. Tumor specimens were assessed for various clinicopathologic features, including levels of tumor cell Ki-67 expression. Associations of these features with death from RCC were evaluated using Cox proportional hazards regression models. RESULTS At last follow-up, 396 patients had died, including 238 who died from ccRCC at a median of 2.1 years after surgery. Although tumor cell Ki-67 expression and coagulative tumor necrosis were highly correlated, the prognostic information conveyed by these 2 markers failed to overlap. For the subset of patients with necrotic tumors, high levels of Ki-67 more than doubled the risk of death from RCC (risk ratio, 2.18; 95% confidence interval [CI], 1.52-3.11; P < .001). For patients with tumors lacking necrosis, high levels of Ki-67 expression were similarly correlated with an increased risk of death from RCC (risk ratio, 2.50; 95% CI, 1.66-3.77; P < .001). CONCLUSIONS Prognostic information conveyed by Ki-67 and coagulative tumor necrosis are not interchangeable. Thus, Ki-67 and coagulative tumor necrosis should not be treated as surrogates for one another and both of these features should be evaluated when generating outcome predictions for patients with ccRCC.
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Affiliation(s)
- Matthew K Tollefson
- Department of Urology, Mayo Clinic and Mayo Medical School, Rochester, MN 55905, USA
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Ma N, Matsunaga S, Takata H, Ono-Maniwa R, Uchiyama S, Fukui K. Nucleolin functions in nucleolus formation and chromosome congression. J Cell Sci 2007; 120:2091-105. [PMID: 17535846 DOI: 10.1242/jcs.008771] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
A complex structure, designated the chromosome periphery, surrounds each chromosome during mitosis. Although several proteins have been shown to localize to the chromosome periphery, their functions during mitosis remain unclear. Here, we used a combination of high-resolution microscopy and RNA-interference-mediated depletion to study the functions of nucleolin, a nucleolar protein localized at the chromosome periphery, in interphase and mitosis. During mitosis, nucleolin was localized in the peripheral region including the vicinity of the outer kinetochore of chromosomes. Staining with an antibody specific for nucleolin phosphorylated by CDC2 revealed that nucleolin was also associated with the spindle poles from prometaphase to anaphase. Nucleolin depletion resulted in disorganization of the nucleoli at interphase. Furthermore, nucleolin-depleted cells showed a prolonged cell cycle with misaligned chromosomes and defects in spindle organization. The misaligned chromosomes showed syntelic kinetochore-microtubule attachments with reduced centromere stretching. Taken together, our results indicate that nucleolin is required for nucleolus formation, and is also involved in chromosome congression and spindle formation.
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Affiliation(s)
- Nan Ma
- Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita 565-0871, Osaka, Japan
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