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Liu D, Shaukat Z, Hussain R, Khan M, Gregory SL. Drosophila as a model for chromosomal instability. AIMS GENETICS 2021. [DOI: 10.3934/genet.2015.1.1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
AbstractChromosomal instability (CIN) is a common feature of tumours that leads to increased genetic diversity in the tumour and poor clinical outcomes. There is considerable interest in understanding how CIN comes about and how its contribution to drug resistance and metastasis might be counteracted. In the last decade a number of CIN model systems have been developed in Drosophila that offer unique benefits both in understanding the development of CIN in a live animal as well as giving the potential to do genome wide screens for therapeutic candidate genes. This review outlines the mechanisms used in several Drosophila CIN model systems and summarizes some significant outcomes and opportunities that they have produced.
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Affiliation(s)
- Dawei Liu
- School of Molecular and Biomedical Science, University of Adelaide, North Terrace, Adelaide S.A. 5006, Australia
| | - Zeeshan Shaukat
- School of Molecular and Biomedical Science, University of Adelaide, North Terrace, Adelaide S.A. 5006, Australia
| | - Rashid Hussain
- School of Molecular and Biomedical Science, University of Adelaide, North Terrace, Adelaide S.A. 5006, Australia
| | - Mahwish Khan
- School of Molecular and Biomedical Science, University of Adelaide, North Terrace, Adelaide S.A. 5006, Australia
| | - Stephen L. Gregory
- School of Molecular and Biomedical Science, University of Adelaide, North Terrace, Adelaide S.A. 5006, Australia
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2
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Hickman KA, Hariharan S, De Melo J, Ylanko J, Lustig LC, Penn LZ, Andrews DW. Image-Based Analysis of Protein Stability. Cytometry A 2020; 97:363-377. [PMID: 31774248 PMCID: PMC7187295 DOI: 10.1002/cyto.a.23928] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 10/28/2019] [Accepted: 10/29/2019] [Indexed: 12/14/2022]
Abstract
Short half-life proteins regulate many essential processes, including cell cycle, transcription, and apoptosis. However, few well-characterized protein-turnover pathways have been identified because traditional methods to measure protein half-life are time and labor intensive. To overcome this barrier, we developed a protein stability probe and high-content screening pipeline for novel regulators of short half-life proteins using automated image analysis. Our pilot probe consists of the short half-life protein c-MYC (MYC) fused to Venus fluorescent protein (MYC-Venus). This probe enables protein half-life to be scored as a function of fluorescence intensity and distribution. Rapid turnover prevents maximal fluorescence of the probe due to the relatively longer maturation time of the fluorescent protein. Cells expressing the MYC-Venus probe were analyzed using a pipeline in which automated confocal microscopy and image analyses were used to score MYC-Venus stability by two strategies: assaying the percentage of cells with Venus fluorescence above background, and phenotypic comparative analysis. To evaluate this high-content screening pipeline and our probe, a kinase inhibitor library was screened by confocal microscopy to identify known and novel kinases that regulate MYC stability. Compounds identified were shown to increase the half-life of both MYC-Venus and endogenous MYC, validating the probe and pipeline. Fusion of another short half-life protein, myeloid cell leukemia 1 (MCL1), with Venus also demonstrated an increase in percent Venus-positive cells after treatment with inhibitors known to stabilize MCL1. Together, the results validate the use of our automated microscopy and image analysis pipeline of stability probe-expressing cells to rapidly and quantitatively identify regulators of short half-life proteins. © 2019 The Authors. Cytometry Part A published by Wiley Periodicals, Inc. on behalf of International Society for Advancement of Cytometry.
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Affiliation(s)
- K. Ashley Hickman
- Sunnybrook Research InstituteTorontoON M4N 3M5Canada
- Princess Margaret Cancer CenterTorontoON M5G 1L7Canada
- Faculty of Medicine, Department of Medical BiophysicsUniversity of TorontoTorontoON M5G 1L7Canada
| | - Santosh Hariharan
- Sunnybrook Research InstituteTorontoON M4N 3M5Canada
- Faculty of Medicine, Department of Medical BiophysicsUniversity of TorontoTorontoON M5G 1L7Canada
| | - Jason De Melo
- Princess Margaret Cancer CenterTorontoON M5G 1L7Canada
| | - Jarkko Ylanko
- Sunnybrook Research InstituteTorontoON M4N 3M5Canada
| | - Lindsay C. Lustig
- Princess Margaret Cancer CenterTorontoON M5G 1L7Canada
- Faculty of Medicine, Department of Medical BiophysicsUniversity of TorontoTorontoON M5G 1L7Canada
| | - Linda Z. Penn
- Princess Margaret Cancer CenterTorontoON M5G 1L7Canada
- Faculty of Medicine, Department of Medical BiophysicsUniversity of TorontoTorontoON M5G 1L7Canada
| | - David W. Andrews
- Sunnybrook Research InstituteTorontoON M4N 3M5Canada
- Faculty of Medicine, Department of Medical BiophysicsUniversity of TorontoTorontoON M5G 1L7Canada
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Dai D, Zhou B, Xu W, Jin H, Wang X. CHFR Promoter Hypermethylation Is Associated with Gastric Cancer and Plays a Protective Role in Gastric Cancer Process. J Cancer 2019; 10:949-956. [PMID: 30854101 PMCID: PMC6400794 DOI: 10.7150/jca.27224] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Accepted: 12/05/2018] [Indexed: 12/18/2022] Open
Abstract
Background: Chromosomally unstable tumors account for 50% of gastric cancer. CHFR plays a role in controlling chromosomal instability and its inactivation will eventually lead to tumorigenesis. In addition to genetic deletion, DNA methylation could silence the expression of many cancer-related genes including CHFR. Its methylation was found to be associated with the initiation and progression of gastric cancer. Methods: We performed a meta-analysis involving methylation analyses of CHFR promoter in gastric cancer. Nineteen studies with 1,249 tumor tissues and 745 normal tissues had been included in current study. Results: We found that CHFR methylation was significantly higher in gastric cancer (studies numbers = 15, cases/controls = 862/745, odds ratio (OR) = 7.46, 95% confidence index (95% CI) = 4.99-11.14). Methylation array data was also obtained from Gene Expression Omnibus (GEO) and The Cancer Genome Atlas network (TCGA). There were 7 out of 13 CHFR methylation probes target to the same CpG island region (hg19, 131973620-131975130) showed the CHFR methylation was higher in gastric cancers than normal controls. Eight probes showed CHFR promoter hypermethylation was associated with longer overall survival of gastric cancer patients (Hazard Ratio < 1). Conclusions: The CHFR promoter hypermethylation was associated with gastric cancer and played a protective role in gastric cancer process. Its methylation could be a potential biomarker for the diagnosis and prognosis of gastric cancer.
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Affiliation(s)
- Dongjun Dai
- Department of Medical Oncology, Sir Run Run Shaw Hospital, Medical School of Zhejiang University, Hangzhou, China
| | - Bingluo Zhou
- Laboratory of Cancer Biology, Key Lab of Biotherapy, Sir Run Run Shaw Hospital, Medical School of Zhejiang University, Hangzhou, China
| | - Wenxia Xu
- Laboratory of Cancer Biology, Key Lab of Biotherapy, Sir Run Run Shaw Hospital, Medical School of Zhejiang University, Hangzhou, China
| | - Hongchuan Jin
- Laboratory of Cancer Biology, Key Lab of Biotherapy, Sir Run Run Shaw Hospital, Medical School of Zhejiang University, Hangzhou, China
| | - Xian Wang
- Department of Medical Oncology, Sir Run Run Shaw Hospital, Medical School of Zhejiang University, Hangzhou, China
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Brown A, Geiger H. Chromosome integrity checkpoints in stem and progenitor cells: transitions upon differentiation, pathogenesis, and aging. Cell Mol Life Sci 2018; 75:3771-3779. [PMID: 30066086 PMCID: PMC6154040 DOI: 10.1007/s00018-018-2891-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 07/22/2018] [Accepted: 07/25/2018] [Indexed: 01/30/2023]
Abstract
Loss of chromosome integrity is a major contributor to cancer. Checkpoints within the cell division cycle that facilitate the accuracy and outcome of chromosome segregation are thus critical pathways for preserving chromosome integrity and preventing chromosomal instability. The spindle assembly checkpoint, the decatenation checkpoint and the post-mitotic tetraploidy checkpoint ensure the appropriate establishment of the spindle apparatus, block mitotic entry upon entanglement of chromosomes or prevent further progression of post-mitotic cells that display massive spindle defects. Most of our knowledge on these mechanisms originates from studies conducted in yeast, cancer cell lines and differentiated cells. Considering that in many instances cancer derives from transformed stem and progenitor cells, our knowledge on these checkpoints in these cells just started to emerge. With this review, we provide a general overview of the current knowledge of these checkpoints in embryonic as well as in adult stem and progenitor cells with a focus on the hematopoietic system and outline common mis-regulations of their function associated with cancer and leukemia. Most cancers are aging-associated diseases. We will thus also discuss changes in the function and outcome of these checkpoints upon aging of stem and progenitor cells.
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Affiliation(s)
- Andreas Brown
- Institute of Molecular Medicine, Ulm University, Life Science Building N27, James Franck-Ring/Meyerhofstrasse, 89081, Ulm, Germany
| | - Hartmut Geiger
- Institute of Molecular Medicine, Ulm University, Life Science Building N27, James Franck-Ring/Meyerhofstrasse, 89081, Ulm, Germany.
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH, 45229, USA.
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The inhibition of UBC13 expression and blockage of the DNMT1-CHFR-Aurora A pathway contribute to paclitaxel resistance in ovarian cancer. Cell Death Dis 2018; 9:93. [PMID: 29367628 PMCID: PMC5833742 DOI: 10.1038/s41419-017-0137-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 09/03/2017] [Accepted: 11/08/2017] [Indexed: 12/14/2022]
Abstract
Paclitaxel is widely used as a first-line chemotherapeutic drug for patients with ovarian cancer and other solid cancers, but drug resistance occurs frequently, resulting in ovarian cancer still presenting as the highest lethality among all gynecological tumors. Here, using DIGE quantitative proteomics, we identified UBC13 as down-regulated in paclitaxel-resistant ovarian cancer cells, and it was further revealed by immunohistochemical staining that UBC13 low-expression was associated with poorer prognosis and shorter survival of the patients. Through gene function experiments, we found that paclitaxel exposure induced UBC13 down-regulation, and the enforced change in UBC13 expression altered the sensitivity to paclitaxel. Meanwhile, the reduction of UBC13 increased DNMT1 levels by attenuating its ubiquitination, and the up-regulated DNMT1 enhanced the CHFR promoter DNA methylation levels, leading to a reduction of CHFR expression, and an increased in the levels of Aurora A. Our findings revealed a novel function for UBC13 in regulating paclitaxel sensitivity through a DNMT1-CHFR-Aurora A pathway in ovarian cancer cells. UBC13 could potentially be employed as a therapeutic molecular drug for reversing paclitaxel resistance in ovarian cancer patients.
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6
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Ding Y, Lian HF, Du Y. Clinicopathological significance of CHFR promoter methylation in gastric cancer: a meta-analysis. Oncotarget 2017. [PMID: 29515792 PMCID: PMC5839373 DOI: 10.18632/oncotarget.23394] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The mitotic checkpoint gene (CHFR) (Checkpoint with Forkhead-associated and Ring finger domains is a G2 phase/mitosis checkpoint and tumor-suppressor gene. Recent studies have reported the relationship of CHFR promoter methylation with clinicopathological significance of gastric cancer. However, the results remain unclear due to small size of sample. We pooled 15 studies including 827 gastric cancer patients and conducted a meta-analysis to investigate the clinicopathological significance of CHFR promoter methylation in gastric cancer. Our data revealed that the frequency of CHFR promoter methylation was higher in gastric cancer than in normal gastric tissue, Odd Ratio (OR) was 10.12 with 95% CI 5.17–19.79, p < 0.00001. Additionally, the rate of CHFR promoter methylation was significantly increased in high grade of gastric cancer compared to low grade, OR was 1.64 with 95% CI 1.00–2.68, p = 0.05. CHFR methylation was significantly associated with the positive lymph node metastasis, OR was 1.56 with 95% CI 1.05–2.32, p = 0.03. We concluded that CHFR could serve as a biomarker for diagnosis of gastric cancer, and a drug target for development of gene therapy in gastric cancer. CHFR promoter methylation is associated with tumor poor differentiation and lymph node metastasis.
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Affiliation(s)
- Yong Ding
- School of Basic Medical Science, Henan University, Kaifeng, 475004, China
| | - Hai-Feng Lian
- Department of Gastroenterology, Affiliated Hospital of Binzhou Medical College, Binzhou, 256600, China
| | - Yaowu Du
- Laboratory for Nanomedicine, School of Basic Medical Science, Henan University, Kaifeng, 475004, China
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7
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Wang C, Ma W, Wei R, Zhang X, Shen N, Shang L, E L, Wang Y, Gao L, Li X, Wang B, Zhang Y, Du A. Clinicopathological significance of CHFR methylation in non-small cell lung cancer: a systematic review and meta-analysis. Oncotarget 2017; 8:109732-109739. [PMID: 29312643 PMCID: PMC5752556 DOI: 10.18632/oncotarget.21962] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 09/25/2017] [Indexed: 11/25/2022] Open
Abstract
Checkpoint with Forkhead-associated and Ring finger domains (CHFR) is a G2/M checkpoint and tumor-suppressor gene. Recent publications showed the correlation of CHFR promoter methylation with clinicopathological significance of non-small cell lung cancer (NSCLC), however, the results remain inconsistent. The aim of this study is to investigate the Clinicopathological significance of CHFR promoter methylation in NSCLC with a meta-analysis. A total of nine studies were included in the meta-analysis that 816 patients were involved. Our data indicated that the frequency of CHFR promoter methylation was higher in NSCLC than in normal lung tissue, Odd Ratios (OR) was 9.92 with 95% corresponding confidence interval (CI) 2.17-45.23, p = 0.003. Further subgroup analysis revealed that CHFR promoter was more frequently methylated in squamous cell carcinoma (SCC) than in adenocarcinoma (ADC), OR was 4.46 with 95% CI 1.65-12.05, p = 0.003, suggesting the mechanism of SCC pathogenesis is different from ADC. Notably, CHFR promoter methylation was correlated with smoking behavior in NSCLC. In conclusion, CHFR could be a biomarker for diagnosis of NSCLC, and a promising drug target for development of gene therapy in SCC. CHFR promoter methylation is potentially associated with poor overall survival, additional studies need to be carried out for confirmation in future.
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Affiliation(s)
- Chen Wang
- Department of Pathology, The Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, 030001, P.R. China
| | - Wenxia Ma
- Department of Pathology, The Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, 030001, P.R. China
| | - Rong Wei
- Department of Pathology, The Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, 030001, P.R. China
| | - Xiaoqin Zhang
- Department of Pathology, The Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, 030001, P.R. China
| | - Ningning Shen
- Department of Pathology, The Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, 030001, P.R. China
| | - Lifang Shang
- Department of Pathology, The Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, 030001, P.R. China
| | - Li E
- Department of Pathology, The Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, 030001, P.R. China
| | - Ying Wang
- Department of Pathology, The Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, 030001, P.R. China
| | - Lifang Gao
- Department of Pathology, The Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, 030001, P.R. China
| | - Xin Li
- Department of Pathology, The Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, 030001, P.R. China
| | - Bin Wang
- Department of Pathology, The Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, 030001, P.R. China
| | - Yaping Zhang
- Department of Pathology, The Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, 030001, P.R. China
| | - Aiping Du
- Department of Pathology, The Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, 030001, P.R. China
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Derks S, Cleven AHG, Melotte V, Smits KM, Brandes JC, Azad N, van Criekinge W, de Bruïne AP, Herman JG, van Engeland M. Emerging evidence for CHFR as a cancer biomarker: from tumor biology to precision medicine. Cancer Metastasis Rev 2015; 33:161-71. [PMID: 24375389 PMCID: PMC3988518 DOI: 10.1007/s10555-013-9462-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Novel insights in the biology of cancer have switched the paradigm of a “one-size-fits-all” cancer treatment to an individualized biology-driven treatment approach. In recent years, a diversity of biomarkers and targeted therapies has been discovered. Although these examples accentuate the promise of personalized cancer treatment, for most cancers and cancer subgroups no biomarkers and effective targeted therapy are available. The great majority of patients still receive unselected standard therapies with no use of their individual molecular characteristics. Better knowledge about the underlying tumor biology will lead the way toward personalized cancer treatment. In this review, we summarize the evidence for a promising cancer biomarker: checkpoint with forkhead and ring finger domains (CHFR). CHFR is a mitotic checkpoint and tumor suppressor gene, which is inactivated in a diverse group of solid malignancies, mostly by promoter CpG island methylation. CHFR inactivation has shown to be an indicator of poor prognosis and sensitivity to taxane-based chemotherapy. Here we summarize the current knowledge of altered CHFR expression in cancer, the impact on tumor biology and implications for personalized cancer treatment.
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Affiliation(s)
- Sarah Derks
- Department of Medical Oncology, Cancer Center Amsterdam, VU University Medical Center, Amsterdam, The Netherlands
| | - Arjen H. G. Cleven
- Department of Pathology, GROW-School for Oncology and Developmental Biology, Maastricht University Medical Center, 6200 MD Maastricht, The Netherlands
| | - Veerle Melotte
- Department of Pathology, GROW-School for Oncology and Developmental Biology, Maastricht University Medical Center, 6200 MD Maastricht, The Netherlands
| | - Kim M. Smits
- Department of Radiation Oncology (MAASTRO Clinic), GROW-School for Oncology and Developmental Biology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Johann C. Brandes
- Department of Hematology and Oncology, Atlanta VA Medical Center Winship Cancer Institute, Emory University, Atlanta, GA USA
| | - Nilofer Azad
- Department of Gastrointestinal Oncology, The Sidney Kimmel Comprehensive Cancer Center at the Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Wim van Criekinge
- Department of Mathematical Modelling, Statistics and Bioinformatics, Ghent University, Ghent, Belgium
- MDxHealth, Irvine, CA USA
| | - Adriaan P. de Bruïne
- Department of Pathology, GROW-School for Oncology and Developmental Biology, Maastricht University Medical Center, 6200 MD Maastricht, The Netherlands
| | - James G. Herman
- Department of Tumor Biology, The Sidney Kimmel Comprehensive Cancer Center at the Johns Hopkins University School of Medicine, Baltimore, MD USA
| | - Manon van Engeland
- Department of Pathology, GROW-School for Oncology and Developmental Biology, Maastricht University Medical Center, 6200 MD Maastricht, The Netherlands
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9
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Chen T, Sun Y, Ji P, Kopetz S, Zhang W. Topoisomerase IIα in chromosome instability and personalized cancer therapy. Oncogene 2014; 34:4019-31. [PMID: 25328138 PMCID: PMC4404185 DOI: 10.1038/onc.2014.332] [Citation(s) in RCA: 125] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 09/08/2014] [Accepted: 09/08/2014] [Indexed: 12/29/2022]
Abstract
Genome instability is a hallmark of cancer cells. Chromosome instability (CIN), which is often mutually exclusive from hypermutation genotypes, represents a distinct subtype of genome instability. Hypermutations in cancer cells are due to defects in DNA repair genes, but the cause of CIN is still elusive. However, because of the extensive chromosomal abnormalities associated with CIN, its cause is likely a defect in a network of genes that regulate mitotic checkpoints and chromosomal organization and segregation. Emerging evidence has shown that the chromosomal decatenation checkpoint, which is critical for chromatin untangling and packing during genetic material duplication, is defective in cancer cells with CIN. The decatenation checkpoint is known to be regulated by a family of enzymes called topoisomerases. Among them, the gene encoding topoisomerase IIα (TOP2A) is commonly altered at both gene copy number and gene expression level in cancer cells. Thus, abnormal alterations of TOP2A, its interacting proteins, and its modifications may play a critical role in CIN in human cancers. Clinically, a large arsenal of topoisomerase inhibitors have been used to suppress DNA replication in cancer. However, they often lead to the secondary development of leukemia because of their effect on the chromosomal decatenation checkpoint. Therefore, topoisomerase drugs must be used judiciously and administered on an individual basis. In this review, we highlight the biological function of TOP2A in chromosome segregation and the mechanisms that regulate this enzyme's expression and activity. We also review the roles of TOP2A and related proteins in human cancers, and raise a perspective for how to target TOP2A in personalized cancer therapy.
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Affiliation(s)
- T Chen
- 1] Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA [2] Department of Endoscopy Center, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Y Sun
- Department of Pathology, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - P Ji
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - S Kopetz
- Department of Gastrointestinal Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - W Zhang
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
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Maciejczyk A, Szelachowska J, Czapiga B, Matkowski R, Hałoń A, Györffy B, Surowiak P. Elevated BUBR1 expression is associated with poor survival in early breast cancer patients: 15-year follow-up analysis. J Histochem Cytochem 2013; 61:330-9. [PMID: 23392733 DOI: 10.1369/0022155413480148] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
BUBR1 (budding uninhibited by benzimidazole-related 1) represents the component of a controlling complex in mitosis. Defects in mitotic control complex result in chromosomal instability and, as a result, disturb the mitotic process. This study was aimed at examining the prognostic value linked to the expression of BUBR1 in a group of patients with breast cancer. We analyzed the expression of BUBR1 in 98 stage II breast cancer patients with a median follow-up of 15 years. Immunohistochemical reactions were performed using monoclonal antibodies against BUBR1. We also studied the prognostic value of BUBR1 mRNA expression using the Kaplan-Meier (KM) plotter, which assessed the effect of 22,277 genes on survival in 2422 breast cancer patients. A background database was established using gene expression data and survival information on 2422 patients downloaded from the Gene Expression Omnibus (GEO; Affymetrix HGU133A and HGU133+2 microarrays). The median relapse-free survival was 6.43 years. Univariate and multivariate analyses showed that higher expression of BUBR1 was typical for cases of shorter overall survival, disease-free time, and disease-specific survival. KM plotter analysis showed that elevated BUBR1 mRNA expression had a negative impact on patients' relapse-free, distant metastases-free, and overall survival. Elevated BUBR1 expression was associated with poor survival in early stage breast cancer patients.
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11
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Egeberg DL, Lethan M, Manguso R, Schneider L, Awan A, Jørgensen TS, Byskov AG, Pedersen LB, Christensen ST. Primary cilia and aberrant cell signaling in epithelial ovarian cancer. Cilia 2012; 1:15. [PMID: 23351307 PMCID: PMC3555760 DOI: 10.1186/2046-2530-1-15] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Accepted: 05/01/2012] [Indexed: 12/14/2022] Open
Abstract
Background Ovarian cancer is the fourth leading cause of cancer-related deaths among women in Denmark, largely due to the advanced stage at diagnosis in most patients. Approximately 90% of ovarian cancers originate from the single-layered ovarian surface epithelium (OSE). Defects in the primary cilium, a solitary sensory organelle in most cells types including OSE, were recently implicated in tumorigenesis, mainly due to deregulation of ciliary signaling pathways such as Hedgehog (Hh) signaling. However, a possible link between primary cilia and epithelial ovarian cancer has not previously been investigated. Methods The presence of primary cilia was analyzed in sections of fixed human ovarian tissue as well as in cultures of normal human ovarian surface epithelium (OSE) cells and two human OSE-derived cancer cell lines. We also used immunofluorescence microscopy, western blotting, RT-PCR and siRNA to investigate ciliary signaling pathways in these cells. Results We show that ovarian cancer cells display significantly reduced numbers of primary cilia. The reduction in ciliation frequency in these cells was not due to a failure to enter growth arrest, and correlated with persistent centrosomal localization of aurora A kinase (AURA). Further, we demonstrate that ovarian cancer cells have deregulated Hh signaling and platelet-derived growth factor receptor alpha (PDGFRα) expression and that promotion of ciliary formation/stability by AURA siRNA depletion decreases Hh signaling in ovarian cancer cells. Lastly, we show that the tumor suppressor protein and negative regulator of AURA, checkpoint with forkhead-associated and ring finger domains (CHFR), localizes to the centrosome/primary cilium axis. Conclusions Our results suggest that primary cilia play a role in maintaining OSE homeostasis and that the low frequency of primary cilia in cancer OSE cells may result in part from over-expression of AURA, leading to aberrant Hh signaling and ovarian tumorigenesis.
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Affiliation(s)
- Dorte L Egeberg
- Department of Biology, University of Copenhagen, Universitetsparken 13, 2100, Copenhagen, Denmark.
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Sanbhnani S, Yeong FM. CHFR: a key checkpoint component implicated in a wide range of cancers. Cell Mol Life Sci 2012; 69:1669-87. [PMID: 22159584 PMCID: PMC11114665 DOI: 10.1007/s00018-011-0892-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2011] [Revised: 11/13/2011] [Accepted: 11/16/2011] [Indexed: 02/06/2023]
Abstract
CHFR (Checkpoint with Forkhead-associated and RING finger domains) has been implicated in a checkpoint regulating entry into mitosis. However, the details underlying its roles and regulation are unclear due to conflicting lines of evidence supporting different notions of its functions. We provide here an overview of how CHFR is thought to contribute towards regulating mitotic entry and present possible explanations for contradictory observations published on the functions and regulation of CHFR. Furthermore, we survey key data showing correlations between promoter hypermethylation or down-regulation of CHFR and cancers, with a view on the likely reasons why different extents of correlations have been reported. Lastly, we explore the possibilities of exploiting CHFR promoter hypermethylation status in diagnostics and therapeutics for cancer patients. With keen interest currently focused on the association between hypermethylation of CHFR and cancers, details of how CHFR functions require further study to reveal how its absence might possibly contribute to tumorigenesis.
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Affiliation(s)
- Sheru Sanbhnani
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 8 Medical Drive, Singapore
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Gonzalez ME, DuPrie ML, Krueger H, Merajver SD, Ventura AC, Toy KA, Kleer CG. Histone methyltransferase EZH2 induces Akt-dependent genomic instability and BRCA1 inhibition in breast cancer. Cancer Res 2011; 71:2360-70. [PMID: 21406404 DOI: 10.1158/0008-5472.can-10-1933] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Increased levels of EZH2, a critical regulator of cellular memory, signal the presence of metastasis and poor outcome in breast cancer patients. High levels of EZH2 are associated with nuclear pleomorphism, lack of estrogen receptor expression, and decreased nuclear levels of BRCA1 tumor suppressor protein in invasive breast carcinomas. The mechanism by which EZH2 overexpression promotes the growth of poorly differentiated invasive carcinomas remains to be defined. Here, we show that EZH2 controls the intracellular localization of BRCA1 protein. Conditional doxycycline-induced upregulation of EZH2 in benign mammary epithelial cells results in nuclear export of BRCA1 protein, aberrant mitoses with extra centrosomes, and genomic instability. EZH2 inhibition in CAL51 breast cancer cells induces BRCA1 nuclear localization and rescues defects in ploidy and mitosis. Mechanistically, EZH2 overexpression is sufficient for activation of the phosphoinositide 3-kinase/Akt (PI3K/Akt) pathway specifically through activation of Akt isoform 1. EZH2-induced BRCA1 nuclear export, aneuploidy, and mitotic defects were prevented by treatment with the PI3K inhibitors LY294002 or wortmannin. Targeted inhibition of Akt-1, Akt-2, and Akt-3 isoforms revealed that the EZH2-induced phenotype requires specific activation of Akt-1. The relevance of our studies to human breast cancer is highlighted by the finding that high EZH2 protein levels are associated with upregulated expression of phospho-Akt-1 (Ser473) and decreased nuclear expression of phospho-BRCA1 (Ser1423) in 39% of invasive breast carcinomas. These results enable us to pinpoint one mechanism by which EZH2 regulates BRCA1 expression and genomic stability mediated by the PI3K/Akt-1 pathway.
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Affiliation(s)
- Maria E Gonzalez
- Department of Pathology, Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, Michigan 48109, USA
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14
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CHFR: A Novel Mitotic Checkpoint Protein and Regulator of Tumorigenesis. Transl Oncol 2011; 1:57-64. [PMID: 18633460 DOI: 10.1593/tlo.08109] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2008] [Revised: 04/02/2008] [Accepted: 05/12/2008] [Indexed: 12/30/2022] Open
Abstract
Checkpoint with FHA and RING finger domains (CHFR) was first recognized as an early mitotic checkpoint protein that delayed the cell cycle in response to microtubule-targeting drugs. It is an E3 ubiquitin ligase that ubiquitinates target proteins to direct them to the proteasome for degradation or to alter their activity. To date, however, the downstream target proteins critical to CHFR's normal cellular functions largely remain unidentified with the exception of the key mitosis regulators, and oncogenes, PLK1 and Aurora A kinases. Rapidly growing evidence in mice, primary human tumors, and mammalian cell culture models indicate that CHFR may also function as a potent tumor suppressor. Interestingly, studies reported to date suggest that CHFR both controls a novel prophase checkpoint early in mitosis and regulates chromosome segregation later in mitosis to maintain genomic stability. In addition, loss of CHFR sensitizes cancer cells to microtubule poisons, altering chemoresponsiveness to taxanes and making it a potential biomarker for chemotherapeutic response. Importantly, CHFR may be one of the few proteins that are required for regulating the cell cycle and maintaining genomic instability to inhibit tumorigenesis.
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15
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Keller JA, Petty EM. CHFR binds to and regulates MAD2 in the spindle checkpoint through its cysteine-rich domain. Biochem Biophys Res Commun 2011; 409:389-93. [PMID: 21575600 DOI: 10.1016/j.bbrc.2011.04.143] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Accepted: 04/29/2011] [Indexed: 12/30/2022]
Abstract
CHFR has been implicated as a tumor suppressor in a multitude of cancers. It was originally identified as a major component of the antephase checkpoint. Recently, CHFR was reported to interact with MAD2, an important component of the spindle assembly checkpoint, where CHFR knockdown resulted in mislocalization of MAD2 and disruption of the MAD2/CDC20 interaction. To further understand how CHFR interacts with MAD2, we deleted key functional domains of CHFR, and investigated the effect on MAD2 binding and function. Here we show that deletion of the cysteine-rich domain of CHFR is required for the CHFR/MAD2 interaction as well as proper localization of MAD2 in the cell. Furthermore, the cysteine-rich domain deletion exhibits impaired ability to promote the MAD2/CDC20 interaction, leading to an increase in mitotic defects relative to wild type CHFR. These data support a critical role for CHFR in the MAD2 spindle checkpoint. Furthermore, these data establish the cysteine-rich domain of CHFR as the essential domain for the CHFR/MAD2 interaction and for promoting interaction between MAD2 and CDC20 to inhibit the anaphase-promoting complex.
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Affiliation(s)
- Jennifer A Keller
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
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16
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Ma T, Keller JA, Yu X. RNF8-dependent histone ubiquitination during DNA damage response and spermatogenesis. Acta Biochim Biophys Sin (Shanghai) 2011; 43:339-45. [PMID: 21444325 DOI: 10.1093/abbs/gmr016] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Histone ubiquitination regulates the chromatin structure that is important for many biological processes. Recently, ubiquitination of histones was observed during the DNA damage response (DDR), and this modification is controlled by really interesting new gene (RING) domain E3 ligase, RNF8. Together with the E2 conjugating enzyme UBC13, RNF8 catalyzes ubiquitination of the histones H2A and H2AX during the DDR, thus facilitating downstream recruitment of DDR factors, such as p53 binding protein 1 (53BP1) and breast cancer type 1 susceptibility protein (BRCA1), to the damage site. Accordingly, the RNF8 knockout mice display phenotypes associated with failed DDR, including hypersensitivity to ionizing radiation, V(D)J recombination deficiency, and a predisposition to cancer. In addition to the DDR phenotypes, RNF8 knockout mice fail to generate mature sperm during spermatogenesis, resulting in male sterility. The RNF8 knockout mice also have a drastic reduction in histone ubiquitination in the testes. These findings indicate that the role of histone ubiquitination during chromatin remodeling in two different biological events could be linked by an RNF8-dependent mechanism. Here, we review the molecular mechanism of RNF8-dependent histone ubiquitination both in DDR and spermatogenesis.
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Affiliation(s)
- Teng Ma
- Division of Molecular Medicine and Genetics, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor 48109, USA
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17
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Protected from the inside: Endogenous histone deacetylase inhibitors and the road to cancer. Biochim Biophys Acta Rev Cancer 2011; 1815:241-52. [DOI: 10.1016/j.bbcan.2011.01.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Revised: 01/16/2011] [Accepted: 01/19/2011] [Indexed: 02/06/2023]
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18
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Dinosaurs and ancient civilizations: reflections on the treatment of cancer. Neoplasia 2011; 12:957-68. [PMID: 21170260 DOI: 10.1593/neo.101588] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2010] [Revised: 11/15/2010] [Accepted: 11/15/2010] [Indexed: 12/14/2022] Open
Abstract
Research efforts in the area of palaeopathology have been seen as an avenue to improve our understanding of the pathogenesis of cancer. Answers to questions of whether dinosaurs had cancer, or if cancer plagued ancient civilizations, have captured the imagination as well as the popular media. Evidence for dinosaurian cancer may indicate that cancer may have been with us from the dawn of time. Ancient recorded history suggests that past civilizations attempted to fight cancer with a variety of interventions. When contemplating the issue why a generalized cure for cancer has not been found, it might prove useful to reflect on the relatively limited time that this issue has been an agenda item of governmental attention as well as continued introduction of an every evolving myriad of manmade carcinogens relative to the total time cancer has been present on planet Earth. This article reflects on the history of cancer and the progress made following the initiation of the "era of cancer chemotherapy."
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Soutto M, Peng D, Razvi M, Ruemmele P, Hartmann A, Roessner A, Schneider-Stock R, El-Rifai W. Epigenetic and genetic silencing of CHFR in esophageal adenocarcinomas. Cancer 2010; 116:4033-42. [PMID: 20564104 DOI: 10.1002/cncr.25151] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND The checkpoint with forkhead-associated domain and RING-finger domain (CHFR) is a mitotic checkpoint protein with tumor-suppressor functions. In this study, the authors investigated the epigenetic and genetic mechanisms that regulate CHFR expression in esophageal adenocarcinomas (EACs). METHODS Quantitative reverse transcriptase polymerase chain reaction analysis demonstrated downregulation of CHFR transcript in 79% of EACs (44 of 56) compared with 41 normal samples (P < .001). Immunohistochemical analysis of CHFR protein expression showed absence or weak immunostaining for CHFR in 75% of EACs (56 of 75) compared with normal tissue samples. The authors next examined the promoter DNA hypermethylation of CHFR by using quantitative bisulfite pyrosequencing technology. They detected significant CHFR promoter DNA hypermethylation in 31% of tumor samples (18 of 58) compared with normal samples (P < .001). Treatment of OE33 cells with 5-Aza-deoxycytidine led to reduction in the promoter DNA methylation levels with restoration of the CHFR mRNA expression, which confirmed promoter DNA methylation as an epigenetic mechanism regulating CHFR expression. However, they identified several EACs where the CHFR mRNA expression was silenced in the absence of notable methylation. Therefore, the authors examined the relative DNA copy number level of CHFR compared with normal samples. RESULTS The results confirmed a decrease or absence of the relative CHFR DNA copy number levels in 59% of tumor samples. Nine tumors that showed loss of CHFR mRNA expression, in absence of promoter DNA hypermethylation, demonstrated a significant loss of relative CHFR DNA copy numbers. CONCLUSIONS Taken together, their findings demonstrated that both epigenetic and genetic mechanisms were involved in silencing CHFR expression in EACs.
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Affiliation(s)
- Mohammed Soutto
- Department of Surgery, Vanderbilt-Ingram Cancer Center, Vanderbilt University Medical Center, Nashville, TN 37323, USA
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20
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The War on Cancer rages on. Neoplasia 2010; 11:1252-63. [PMID: 20019833 DOI: 10.1593/neo.91866] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2009] [Revised: 11/03/2009] [Accepted: 11/03/2009] [Indexed: 02/08/2023] Open
Abstract
In 1971, the "War on Cancer" was launched by the US government to cure cancer by the 200-year anniversary of the founding of the United States of America, 1976. This article briefly looks back at the progress that has been made in cancer research and compares progress made in other areas of human affliction. While progress has indeed been made, the battle continues to rage on.
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21
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Abstract
Maintenance of genomic stability is needed for cells to survive many rounds of division throughout their lifetime. Key to the proper inheritance of intact genome is the tight temporal and spatial coordination of cell cycle events. Moreover, checkpoints are present that function to monitor the proper execution of cell cycle processes. For instance, the DNA damage and spindle assembly checkpoints ensure genomic integrity by delaying cell cycle progression in the presence of DNA or spindle damage, respectively. A checkpoint that has recently been gaining attention is the antephase checkpoint that acts to prevent cells from entering mitosis in response to a range of stress agents. We review here what is known about the pathway that monitors the status of the cells at the brink of entry into mitosis when cells are exposed to insults that threaten the proper inheritance of chromosomes. We highlight issues which are unresolved in terms of our understanding of the antephase checkpoint and provide some perspectives on what lies ahead in the understanding of how the checkpoint functions.
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22
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Wickström SA, Masoumi KC, Khochbin S, Fässler R, Massoumi R. CYLD negatively regulates cell-cycle progression by inactivating HDAC6 and increasing the levels of acetylated tubulin. EMBO J 2010; 29:131-44. [PMID: 19893491 PMCID: PMC2775896 DOI: 10.1038/emboj.2009.317] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Accepted: 10/07/2009] [Indexed: 02/02/2023] Open
Abstract
CYLD is a tumour-suppressor gene that is mutated in a benign skin tumour syndrome called cylindromatosis. The CYLD gene product is a deubiquitinating enzyme that was shown to regulate cell proliferation, cell survival and inflammatory responses, mainly through inhibiting NF-kappaB signalling. Here we show that CYLD controls cell growth and division at the G(1)/S-phase as well as cytokinesis by associating with alpha-tubulin and microtubules through its CAP-Gly domains. Translocation of activated CYLD to the perinuclear region of the cell is achieved by an inhibitory interaction of CYLD with histone deacetylase-6 (HDAC6) leading to an increase in the levels of acetylated alpha-tubulin around the nucleus. This facilitates the interaction of CYLD with Bcl-3, leading to a significant delay in the G(1)-to-S-phase transition. Finally, CYLD also interacts with HDAC6 in the midbody where it regulates the rate of cytokinesis in a deubiquitinase-independent manner. Altogether these results identify a mechanism by which CYLD regulates cell proliferation at distinct cell-cycle phases.
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Affiliation(s)
- Sara A Wickström
- Department of Molecular Medicine, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Katarzyna C Masoumi
- Department of Laboratory Medicine, Lund University, Malmö University Hospital, Malmö, Sweden
| | - Saadi Khochbin
- INSERM, U823, Université Joseph Fourier, Institut Albert Bonniot, Grenoble, France
| | - Reinhard Fässler
- Department of Molecular Medicine, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Ramin Massoumi
- Department of Molecular Medicine, Max Planck Institute of Biochemistry, Martinsried, Germany
- Department of Laboratory Medicine, Clinical Research Center, Lund University, Malmö University Hospital, Malmö, Sweden
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23
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SAEKI T, OUCHI M, OUCHI T. Physiological and oncogenic Aurora-A pathway. Int J Biol Sci 2009; 5:758-62. [PMID: 20011137 PMCID: PMC2793309 DOI: 10.7150/ijbs.5.758] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2009] [Accepted: 11/24/2009] [Indexed: 01/03/2023] Open
Abstract
Aurora family of protein kinases have emerged as crucial factors of, not only mitosis and cytokinesis, but also human carcinogenesis. Among these family members is Aurora-A that is frequently overexpressed in varieties of human cancer. Both in vitro and in vivo studies demonstrated that Aurora-A induces tumorigenesis through genome instability. These studies have further shown that cell signaling cross-talk between Aurora-A and other cellular proteins are essential for fully-transformed phenotypes. This review summarizes recent progress of Aurora-A-associated carcinogenesis.
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Affiliation(s)
- Toshiaki SAEKI
- 1. Department of Breast Oncology, Saitama Medical School, Saitama, JAPAN
| | - Mutsuko OUCHI
- 2. NUHS, Systems Biology Program, Pritzker School of Medicine, University of Chicago, Evanston, IL 60201, USA
| | - Toru OUCHI
- 2. NUHS, Systems Biology Program, Pritzker School of Medicine, University of Chicago, Evanston, IL 60201, USA
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24
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Gould CM, Diella F, Via A, Puntervoll P, Gemünd C, Chabanis-Davidson S, Michael S, Sayadi A, Bryne JC, Chica C, Seiler M, Davey NE, Haslam N, Weatheritt RJ, Budd A, Hughes T, Pas J, Rychlewski L, Travé G, Aasland R, Helmer-Citterich M, Linding R, Gibson TJ. ELM: the status of the 2010 eukaryotic linear motif resource. Nucleic Acids Res 2009; 38:D167-80. [PMID: 19920119 PMCID: PMC2808914 DOI: 10.1093/nar/gkp1016] [Citation(s) in RCA: 204] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Linear motifs are short segments of multidomain proteins that provide regulatory functions independently of protein tertiary structure. Much of intracellular signalling passes through protein modifications at linear motifs. Many thousands of linear motif instances, most notably phosphorylation sites, have now been reported. Although clearly very abundant, linear motifs are difficult to predict de novo in protein sequences due to the difficulty of obtaining robust statistical assessments. The ELM resource at http://elm.eu.org/ provides an expanding knowledge base, currently covering 146 known motifs, with annotation that includes >1300 experimentally reported instances. ELM is also an exploratory tool for suggesting new candidates of known linear motifs in proteins of interest. Information about protein domains, protein structure and native disorder, cellular and taxonomic contexts is used to reduce or deprecate false positive matches. Results are graphically displayed in a 'Bar Code' format, which also displays known instances from homologous proteins through a novel 'Instance Mapper' protocol based on PHI-BLAST. ELM server output provides links to the ELM annotation as well as to a number of remote resources. Using the links, researchers can explore the motifs, proteins, complex structures and associated literature to evaluate whether candidate motifs might be worth experimental investigation.
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Affiliation(s)
- Cathryn M Gould
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany
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25
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Fu Z, Regan K, Zhang L, Muders MH, Thibodeau SN, French A, Wu Y, Kaufmann SH, Lingle WL, Chen J, Tindall DJ. Deficiencies in Chfr and Mlh1 synergistically enhance tumor susceptibility in mice. J Clin Invest 2009; 119:2714-24. [PMID: 19690386 DOI: 10.1172/jci37405] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2008] [Accepted: 06/24/2009] [Indexed: 01/17/2023] Open
Abstract
Genetic instability, which leads to an accumulation of various genetic abnormalities, has been considered an essential component of the human neoplasic transformation process. However, the molecular basis of genomic instability during tumorigenesis remains incompletely understood. Growing evidence indicates that checkpoint with forkhead and ring finger domains (CHFR), a recently identified mitotic checkpoint protein, plays an important role in maintaining chromosome integrity and functions as a tumor suppressor. In this study, we used high-throughput technology to conduct gene expression profiling of human colon cancers and found that loss of CHFR expression frequently occurred in colon cancers with high microsatellite instability (MSI-H). Downregulation of CHFR expression was closely associated with overexpression of Aurora A, an important mitotic kinase. Mice with deficiencies in both Chfr and Mlh1 (the gene that encodes the DNA mismatch-repair protein Mlh1) displayed dramatically higher incidence of spontaneous tumors relative to mice deficient for only one of these genes. These results suggest that defects in both Chfr and Mlh1 synergistically increase predisposition to tumorigenesis.
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Affiliation(s)
- Zheng Fu
- Department of Urology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
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26
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Neoplasia: the second decade. Neoplasia 2009; 10:1314-24. [PMID: 19048110 DOI: 10.1593/neo.81372] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2008] [Revised: 10/27/2008] [Accepted: 10/27/2008] [Indexed: 12/30/2022] Open
Abstract
This issue marks the end of the 10-year anniversary of Neoplasia where we have seen exciting growth in both number of submitted and published articles in Neoplasia. Neoplasia was first published in 1999. During the past 10 years, Neoplasia has dynamically adapted to the needs of the cancer research community as technologies have advanced. Neoplasia is currently providing access to articles through PubMed Central to continue to facilitate rapid broad-based dissemination of published findings to the scientific community through an Open Access model. This has in part helped Neoplasia to achieve an improved impact factor this past year, demonstrating that the manuscripts published by Neoplasia are of great interest to the overall cancer research community. This past year, Neoplasia received a record number of articles for review and has had a 21% increase in the number of published articles.
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27
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The story of human cytomegalovirus and cancer: increasing evidence and open questions. Neoplasia 2009; 11:1-9. [PMID: 19107226 DOI: 10.1593/neo.81178] [Citation(s) in RCA: 211] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2008] [Revised: 10/16/2008] [Accepted: 10/16/2008] [Indexed: 02/08/2023] Open
Abstract
Although human cytomegalovirus (HCMV) is generally not regarded to be an oncogenic virus, HCMV infection has been implicated in malignant diseases from different cancer entities. On the basis of our experimental findings, we developed the concept of "oncomodulation" to better explain the role of HCMV in cancer. Oncomodulation means that HCMV infects tumor cells and increases their malignancy. By this concept, HCMV was proposed to be a therapeutic target in a fraction of cancer patients. However, the clinical relevance of HCMV-induced oncomodulation remains to be clarified. One central question that has to be definitively answered is if HCMV establishes persistent virus replication in tumor cells or not. In our eyes, recent clinical findings from different groups in glioblastoma patients and especially the detection of a correlation between the numbers of HCMV-infected glioblastoma cells and tumor stage (malignancy) strongly increase the evidence that HCMV may exert oncomodulatory effects. Here, we summarize the currently available knowledge about the molecular mechanisms that may contribute to oncomodulation by HCMV as well as the clinical findings that suggest that a fraction of tumors from different entities is indeed infected with HCMV.
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28
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Abstract
The role of various p73 isoforms in tumorigenesis has been controversial. However, as we have recently shown, the generation of TAp73-deficient (TAp73(-/-)) mice reveals that TAp73 isoforms exert tumor-suppressive functions, indicating an emerging role for Trp-73 in the maintenance of genomic stability. Unlike mice lacking all p73 isoforms, TAp73(-/-) mice show a high incidence of spontaneous tumors. Moreover, TAp73(-/-) mice are infertile and produce oocytes exhibiting spindle abnormalities. These data suggest a link between TAp73 activities and the common molecular machinery underlying meiosis and mitosis. Previous studies have indicated that the spindle assembly checkpoint (SAC) complex, whose activation leads to mitotic arrest, also regulates meiosis. In this study, we demonstrate in murine and human cells that TAp73 is able to interact directly with several partners of the SAC complex (Bub1, Bub3, and BubR1). We also show that TAp73 is involved in SAC protein localization and activities. Moreover, we show that decreased TAp73 expression correlates with increases of SAC protein expression in patients with lung cancer. Our results establish TAp73 as a regulator of SAC responses and indicate that TAp73 loss can lead to mitotic arrest defects. Our data suggest that SAC impairment in the absence of functional TAp73 could explain the genomic instability and increased aneuploidy observed in TAp73-deficient cells.
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29
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Ricke RM, van Ree JH, van Deursen JM. Whole chromosome instability and cancer: a complex relationship. Trends Genet 2008; 24:457-66. [PMID: 18675487 DOI: 10.1016/j.tig.2008.07.002] [Citation(s) in RCA: 125] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2008] [Revised: 07/10/2008] [Accepted: 07/11/2008] [Indexed: 12/16/2022]
Abstract
Although chromosome mis-segregation is a hallmark of cancer cells, its genetic basis and role in malignant transformation remain poorly understood. In recent years, several mouse models have been generated that harbor gene defects that perturb high-fidelity chromosome segregation. Analysis of these models has revealed that whole chromosome instability (W-CIN) can cause, inhibit or have no effect on tumorigenesis. Here we propose that the effect of W-CIN on tumor development depends on the particular W-CIN gene that is defective, including its other cellular functions, the extent or nature of the gene defect, the affected tissue or cell type and the context of other cancer gene mutations.
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Affiliation(s)
- Robin M Ricke
- Department of Pediatric and Adolescent Medicine, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
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