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Characterization of the Tumor Microenvironment and the Biological Processes with a Role in Prostatic Tumorigenesis. Biomedicines 2022; 10:biomedicines10071672. [PMID: 35884977 PMCID: PMC9313300 DOI: 10.3390/biomedicines10071672] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 06/25/2022] [Accepted: 07/06/2022] [Indexed: 12/25/2022] Open
Abstract
Prostate intratumoral heterogeneity, driven by epithelial−mesenchymal plasticity, contributes to the limited treatment response, and it is therefore necessary to use the biomarkers to improve patient prognostic survival. We aimed to characterize the tumor microenvironment (T lymphocyte infiltration, intratumoral CD34, and KI-67 expressions) by immunohistochemistry methods and to study the biological mechanisms (cell cycle, cell proliferation by adhesion glycoproteins, cell apoptosis) involved in the evolution of the prostate tumor process by flow-cytometry techniques. Our results showed that proliferative activity (S-phase) revealed statistically significant lower values of prostate adenocarcinoma (PCa) and benign prostatic hyperplasia (BPH) reported at non-malignant adjacent cell samples (PCa 4.32 ± 4.91; BPH 2.35 ± 1.37 vs. C 10.23 ± 0.43, p < 0.01). Furthermore, 68% of BPH cases and 88% of patients with PCa had aneuploidy. Statistically increased values of cell proliferation (CD34+ CD61+) were observed in prostate adenocarcinoma and hyperplasia cases reported to non-malignant adjacent cell samples (PCa 28.79 ± 10.14; BPH 40.65 ± 11.88 vs. C 16.15 ± 2.58, p < 0.05). The CD42b+ cell population with a role in cell adhesion, and metastasis had a significantly increased value in PCa cases (38.39 ± 11.23) reported to controls (C 26.24 ± 0.62, p < 0.01). The intratumoral expression of CD34 showed a significantly increased pattern of PCa tissue samples reported to controls (PCa 26.12 ± 6.84 vs. C 1.50 ± 0.70, p < 0.01). Flow cytometric analysis of the cell cycle, apoptosis, and adhesion glycoproteins with a critical role in tumoral cell proliferation, T cell infiltrations, Ki-67, and CD 34 expressions by IHC methods are recommended as techniques for the efficient means of measurement for adenocarcinoma and hyperplasia prostate tissue samples and should be explored in the future.
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San Martin R, Das P, Dos Reis Marques R, Xu Y, Roberts JM, Sanders JT, Golloshi R, McCord RP. Chromosome compartmentalization alterations in prostate cancer cell lines model disease progression. J Cell Biol 2022; 221:212899. [PMID: 34889941 PMCID: PMC8669499 DOI: 10.1083/jcb.202104108] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 08/31/2021] [Accepted: 11/17/2021] [Indexed: 11/22/2022] Open
Abstract
Prostate cancer aggressiveness and metastatic potential are influenced by gene expression and genomic aberrations, features that can be influenced by the 3D structure of chromosomes inside the nucleus. Using chromosome conformation capture (Hi-C), we conducted a systematic genome architecture comparison on a cohort of cell lines that model prostate cancer progression, from normal epithelium to bone metastasis. We describe spatial compartment identity (A-open versus B-closed) changes with progression in these cell lines and their relation to gene expression changes in both cell lines and patient samples. In particular, 48 gene clusters switch from the B to the A compartment, including androgen receptor, WNT5A, and CDK14. These switches are accompanied by changes in the structure, size, and boundaries of topologically associating domains (TADs). Further, compartment changes in chromosome 21 are exacerbated with progression and may explain, in part, the genesis of the TMPRSS2-ERG translocation. These results suggest that discrete 3D genome structure changes play a deleterious role in prostate cancer progression. .
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Affiliation(s)
- Rebeca San Martin
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN
| | - Priyojit Das
- University of Tennessee - Oak Ridge National Lab (UT-ORNL) Graduate School of Genome Science and Technology, University of Tennessee, Knoxville, TN
| | - Renata Dos Reis Marques
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN
| | - Yang Xu
- University of Tennessee - Oak Ridge National Lab (UT-ORNL) Graduate School of Genome Science and Technology, University of Tennessee, Knoxville, TN
| | - Justin M Roberts
- Department of Genitourinary Medical Oncology and the David H. Koch Center for Applied Research of Genitourinary Cancer, University of Texas MD Anderson Cancer Center, Houston, TX
| | - Jacob T Sanders
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN
| | - Rosela Golloshi
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN
| | - Rachel Patton McCord
- Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN
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Saidova AA, Potashnikova DM, Tvorogova AV, Maly IV, Hofmann WA, Vorobjev IA. Specific and reliable detection of Myosin 1C isoform A by RTqPCR in prostate cancer cells. PeerJ 2018; 6:e5970. [PMID: 30498638 PMCID: PMC6251347 DOI: 10.7717/peerj.5970] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 10/19/2018] [Indexed: 12/27/2022] Open
Abstract
Background Prostate cancer (PC) diagnostics and treatment often present a challenging task due to cancer subtype heterogeneity and differential disease progression in patient subgroups. Hence, the critical issue is finding a reliable and sensitive diagnostic and prognostic PC marker, especially for cases of biopsies with low percentages of cancer cells. Isoform A of myosin 1C was shown to be expressed in PC cells and responsible for their invasive properties, however, its feasibility for diagnostic purposes remains to be elucidated. Methods To verify the role of myosin 1C isoform A mRNA expression as a putative prostate cancer marker we performed RT qPCR normalized by three reference genes (GAPDH, YWHAZ, HPRT1) on PC3, RWPE-1, LNCaP and 22Rv1 cell lines. Myosin 1C isoform A detection specificity was confirmed by immunofluorescence staining, cancer and non-cancer prostate cell lines were immunophenotyped by flow cytometry. Results Median normalized mRNA expression level of myosin 1C isoform A in PC cells (PC3 and 22Rv1) is two orders of magnitude higher compared to RWPE-1 cells, which functionally correspond to benign prostate cells. Myosin 1C isoform A expression allows PC cell detection even at a dilution ratio of 1:1000 cancer to non-cancer cells. At the protein level, the mean fluorescence intensity of myosin 1C isoform A staining in PC3 nuclei was only twice as high as in RWPE-1, while the immunophenotypes of both cell lines were similar (CD44+/CD90-/CD133-/CD57-/CD24+-). Conclusions We report a distinct difference in myosin 1C isoform A mRNA levels in malignant (PC3) and benign (RWPE-1) prostate cell lines and suggest a combination of three reference genes for accurate data normalization. For the first time we provide an immunophenotype comparison of RWPE-1 and PC3 cells and demonstrate that RT qPCR analysis of MYO 1C A using appropriate reference genes is sufficient for PC detection even in low-abundance cancer specimens.
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Affiliation(s)
- Aleena A Saidova
- Biological Faculty, M.V. Lomonosov Moscow State University, Moscow, Russia
| | - Daria M Potashnikova
- Biological Faculty, M.V. Lomonosov Moscow State University, Moscow, Russia.,Laboratory of Atherothrombosis, Moscow State University of Medicine and Dentistry, Moscow, Russia
| | - Anna V Tvorogova
- A.N. Belozersky Institute of Physico-Chemical Biology, M.V. Lomonosov Moscow State University, Moscow, Russia
| | - Ivan V Maly
- Department of Physiology and Biophysics, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, United States of America
| | - Wilma A Hofmann
- Department of Physiology and Biophysics, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, United States of America
| | - Ivan A Vorobjev
- Biological Faculty, M.V. Lomonosov Moscow State University, Moscow, Russia.,A.N. Belozersky Institute of Physico-Chemical Biology, M.V. Lomonosov Moscow State University, Moscow, Russia.,Department of Biology, School of Science and Technology, Nazarbayev University, Astana, Kazakhstan
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Guo S, Fan J, Wang B, Xiao M, Li Y, Du J, Peng X. Highly Selective Red-Emitting Fluorescent Probe for Imaging Cancer Cells in Situ by Targeting Pim-1 Kinase. ACS APPLIED MATERIALS & INTERFACES 2018; 10:1499-1507. [PMID: 29219298 DOI: 10.1021/acsami.7b14553] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Based on the fact that enzyme-targeting probes are highly sensitive and selective, a novel red-emitting probe (NB-BF) for Pim-1 kinase including three parts, fluorophore (NB), linker, and inhibitor (BF), has been designed for cancer optical imaging. In its free state, NB-BF is folded and the fluorescence quenched by PET between fluorophore and inhibitor both in PBS buffer and in normal cells. Significantly, it emitted strong red fluorescence in Pim-1 overexpressed cancer cells. The specificity of NB-BF for Pim-1 kinase was directly demonstrated by gene silencing analysis. Furthermore, it is the first time to know where Pim-1 kinase mainly distributes at mitochondria with Pearson's correlation factor (Rr) of 0.965 and to provide a fluorescent tool to verify the function of the Pim-1 kinase. More importantly, NB-BF was applied in tissue imaging and preferentially labeled tumors in vivo.
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Affiliation(s)
- Shigang Guo
- State Key Laboratory of Fine Chemicals and ‡School of Pharmaceutical Science and Technology, Dalian University of Technology , Dalian, 116024, China
| | - Jiangli Fan
- State Key Laboratory of Fine Chemicals and ‡School of Pharmaceutical Science and Technology, Dalian University of Technology , Dalian, 116024, China
| | - Benhua Wang
- State Key Laboratory of Fine Chemicals and ‡School of Pharmaceutical Science and Technology, Dalian University of Technology , Dalian, 116024, China
| | - Ming Xiao
- State Key Laboratory of Fine Chemicals and ‡School of Pharmaceutical Science and Technology, Dalian University of Technology , Dalian, 116024, China
| | - Yueqing Li
- State Key Laboratory of Fine Chemicals and ‡School of Pharmaceutical Science and Technology, Dalian University of Technology , Dalian, 116024, China
| | - Jianjun Du
- State Key Laboratory of Fine Chemicals and ‡School of Pharmaceutical Science and Technology, Dalian University of Technology , Dalian, 116024, China
| | - Xiaojun Peng
- State Key Laboratory of Fine Chemicals and ‡School of Pharmaceutical Science and Technology, Dalian University of Technology , Dalian, 116024, China
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Wang M, Nagle RB, Knudsen BS, Rogers GC, Cress AE. A basal cell defect promotes budding of prostatic intraepithelial neoplasia. J Cell Sci 2017; 130:104-110. [PMID: 27609833 PMCID: PMC5394777 DOI: 10.1242/jcs.188177] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 09/02/2016] [Indexed: 12/15/2022] Open
Abstract
Basal cells in a simple secretory epithelium adhere to the extracellular matrix (ECM), providing contextual cues for ordered repopulation of the luminal cell layer. Early high-grade prostatic intraepithelial neoplasia (HG-PIN) tissue has enlarged nuclei and nucleoli, luminal layer expansion and genomic instability. Additional HG-PIN markers include loss of α6β4 integrin or its ligand laminin-332, and budding of tumor clusters into laminin-511-rich stroma. We modeled the invasive budding phenotype by reducing expression of α6β4 integrin in spheroids formed from two normal human stable isogenic prostate epithelial cell lines (RWPE-1 and PrEC 11220). These normal cells continuously spun in culture, forming multicellular spheroids containing an outer laminin-332 layer, basal cells (expressing α6β4 integrin, high-molecular-weight cytokeratin and p63, also known as TP63) and luminal cells that secrete PSA (also known as KLK3). Basal cells were optimally positioned relative to the laminin-332 layer as determined by spindle orientation. β4-integrin-defective spheroids contained a discontinuous laminin-332 layer corresponding to regions of abnormal budding. This 3D model can be readily used to study mechanisms that disrupt laminin-332 continuity, for example, defects in the essential adhesion receptor (β4 integrin), laminin-332 or abnormal luminal expansion during HG-PIN progression.
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Affiliation(s)
- Mengdie Wang
- Department of Cellular and Molecular Medicine, College of Medicine, University of Arizona Cancer Center, Tucson, AZ 85724, USA
| | - Raymond B Nagle
- Department of Pathology, College of Medicine, University of Arizona Cancer Center, Tucson, AZ 85724, USA
| | - Beatrice S Knudsen
- Department of Pathology and Laboratory Medicine, Cedars Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Gregory C Rogers
- Department of Cellular and Molecular Medicine, College of Medicine, University of Arizona Cancer Center, Tucson, AZ 85724, USA
| | - Anne E Cress
- Department of Cellular and Molecular Medicine, College of Medicine, University of Arizona Cancer Center, Tucson, AZ 85724, USA
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Mosieniak G, Sliwinska MA, Alster O, Strzeszewska A, Sunderland P, Piechota M, Was H, Sikora E. Polyploidy Formation in Doxorubicin-Treated Cancer Cells Can Favor Escape from Senescence. Neoplasia 2016; 17:882-893. [PMID: 26696370 PMCID: PMC4688565 DOI: 10.1016/j.neo.2015.11.008] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 11/11/2015] [Accepted: 11/16/2015] [Indexed: 12/18/2022] Open
Abstract
Cancer cells can undergo stress-induced premature senescence, which is considered to be a desirable outcome of anticancer treatment. However, the escape from senescence and cancer cell repopulation give rise to some doubts concerning the effectiveness of the senescence-induced anticancer therapy. Similarly, it is postulated that polyploidization of cancer cells is connected with disease relapse. We postulate that cancer cell polyploidization associated with senescence is the culprit of atypical cell divisions leading to cancer cell regrowth. Accordingly, we aimed to dissociate between these two phenomena. We induced senescence in HCT 116 cells by pulse treatment with doxorubicin and observed transiently increased ploidy, abnormal nuclear morphology, and various distributions of some proteins (e.g., p21, Ki-67, SA-β-galactosidase) in the subnuclei. Doxorubicin-treated HCT 116 cells displayed an increased production of reactive oxygen species (ROS) possibly caused by an increased amount of mitochondria, which are characterized by low membrane potential. A decrease in the level of ROS by Trolox partially protected the cells from polyploidization but not from senescence. Interestingly, a decreased level of ROS prevented the cells from escaping senescence. We also show that MCF7 cells senesce, but this is not accompanied by the increase of ploidy upon doxorubicin treatment. Moreover, they were stably growth arrested, thus proving that polyploidy but not senescence per se enables to regain the ability to proliferate. Our preliminary results indicate that the different propensity of the HCT 116 and MCF7 cells to increase ploidy upon cell senescence could be caused by a different level of the mTOR and/or Pim-1 kinases.
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Affiliation(s)
- Grazyna Mosieniak
- Laboratory of Molecular Bases of Aging, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, 02-093 Poland.
| | - Malgorzata A Sliwinska
- Laboratory of Molecular Bases of Aging, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, 02-093 Poland.
| | - Olga Alster
- Laboratory of Molecular Bases of Aging, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, 02-093 Poland.
| | - Anna Strzeszewska
- Laboratory of Molecular Bases of Aging, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, 02-093 Poland.
| | - Piotr Sunderland
- Laboratory of Molecular Bases of Aging, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, 02-093 Poland.
| | - Malgorzata Piechota
- Laboratory of Molecular Bases of Aging, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, 02-093 Poland.
| | - Halina Was
- Laboratory of Molecular Bases of Aging, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, 02-093 Poland.
| | - Ewa Sikora
- Laboratory of Molecular Bases of Aging, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Warsaw, 02-093 Poland.
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Wu J, Ivanov AI, Fisher PB, Fu Z. Polo-like kinase 1 induces epithelial-to-mesenchymal transition and promotes epithelial cell motility by activating CRAF/ERK signaling. eLife 2016; 5:e10734. [PMID: 27003818 PMCID: PMC4811775 DOI: 10.7554/elife.10734] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2015] [Accepted: 03/03/2016] [Indexed: 12/22/2022] Open
Abstract
Polo-like kinase 1 (PLK1) is a key cell cycle regulator implicated in the development of various cancers, including prostate cancer. However, the functions of PLK1 beyond cell cycle regulation remain poorly characterized. Here, we report that PLK1 overexpression in prostate epithelial cells triggers oncogenic transformation. It also results in dramatic transcriptional reprogramming of the cells, leading to epithelial-to-mesenchymal transition (EMT) and stimulation of cell migration and invasion. Consistently, PLK1 downregulation in metastatic prostate cancer cells enhances epithelial characteristics and inhibits cell motility. The signaling mechanisms underlying the observed cellular effects of PLK1 involve direct PLK1-dependent phosphorylation of CRAF with subsequent stimulation of the MEK1/2-ERK1/2-Fra1-ZEB1/2 signaling pathway. Our findings highlight novel non-canonical functions of PLK1 as a key regulator of EMT and cell motility in normal prostate epithelium and prostate cancer. This study also uncovers a previously unanticipated role of PLK1 as a potent activator of MAPK signaling.
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Affiliation(s)
- Jianguo Wu
- Department of Human and Molecular Genetics, Virginia Commonwealth University School of Medicine, Richmond, United States
- VCU Institute of Molecular Medicine, Virginia Commonwealth University School of Medicine, Richmond, United States
- VCU Massey Cancer Center, Virginia Commonwealth University School of Medicine, Richmond, United States
| | - Andrei I Ivanov
- Department of Human and Molecular Genetics, Virginia Commonwealth University School of Medicine, Richmond, United States
- VCU Institute of Molecular Medicine, Virginia Commonwealth University School of Medicine, Richmond, United States
- VCU Massey Cancer Center, Virginia Commonwealth University School of Medicine, Richmond, United States
| | - Paul B Fisher
- Department of Human and Molecular Genetics, Virginia Commonwealth University School of Medicine, Richmond, United States
- VCU Institute of Molecular Medicine, Virginia Commonwealth University School of Medicine, Richmond, United States
- VCU Massey Cancer Center, Virginia Commonwealth University School of Medicine, Richmond, United States
| | - Zheng Fu
- Department of Human and Molecular Genetics, Virginia Commonwealth University School of Medicine, Richmond, United States
- VCU Institute of Molecular Medicine, Virginia Commonwealth University School of Medicine, Richmond, United States
- VCU Massey Cancer Center, Virginia Commonwealth University School of Medicine, Richmond, United States
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Transcriptional Dynamics of Immortalized Human Mesenchymal Stem Cells during Transformation. PLoS One 2015; 10:e0126562. [PMID: 25978455 PMCID: PMC4433180 DOI: 10.1371/journal.pone.0126562] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Accepted: 04/03/2015] [Indexed: 12/23/2022] Open
Abstract
Comprehensive analysis of alterations in gene expression along with neoplastic transformation in human cells provides valuable information about the molecular mechanisms underlying transformation. To further address these questions, we performed whole transcriptome analysis to the human mesenchymal stem cell line, UE6E7T-3, which was immortalized with hTERT and human papillomavirus type 16 E6/E7 genes, in association with progress of transformation in these cells. At early stages of culture, UE6E7T-3 cells preferentially lost one copy of chromosome 13, as previously described; in addition, tumor suppressor genes, DNA repair genes, and apoptosis-activating genes were overexpressed. After the loss of chromosome 13, additional aneuploidy and genetic alterations that drove progressive transformation, were observed. At this stage, the cell line expressed oncogenes as well as genes related to anti-apoptotic functions, cell-cycle progression, and chromosome instability (CIN); these pro-tumorigenic changes were concomitant with a decrease in tumor suppressor gene expression. At later stages after prolong culture, the cells exhibited chromosome translocations, acquired anchorage-independent growth and tumorigenicity in nude mice, (sarcoma) and exhibited increased expression of genes encoding growth factor and DNA repair genes, and decreased expression of adhesion genes. In particular, glypican-5 (GPC5), which encodes a cell-surface proteoglycan that might be a biomarker for sarcoma, was expressed at high levels in association with transformation. Patched (Ptc1), the cell surface receptor for hedgehog (Hh) signaling, was also significantly overexpressed and co-localized with GPC5. Knockdown of GPC5 expression decreased cell proliferation, suggesting that it plays a key role in growth in U3-DT cells (transformants derived from UE6E7T-3 cells) through the Hh signaling pathway. Thus, the UE6E7T-3 cell culture model is a useful tool for assessing the functional contribution of genes showed by expression profiling to the neoplastic transformation of human fibroblasts and human mesenchymal stem cells (hMSC).
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Zhang G, Liu Z, Cui G, Wang X, Yang Z. MicroRNA-486-5p targeting PIM-1 suppresses cell proliferation in breast cancer cells. Tumour Biol 2014; 35:11137-45. [PMID: 25104088 DOI: 10.1007/s13277-014-2412-0] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 07/28/2014] [Indexed: 01/07/2023] Open
Abstract
MicroRNAs (miRNAs) are emerging as critical regulators in carcinogenesis and tumor progression. Recently, miR-486-5p has been proved to play an important role in several cancers, but its functions in the context of breast cancer (BC) remain unknown. In this study, we found that miR-486-5p expression is significantly downregulated in BC tissues and cell lines. Overexpression of miR-486-5p dramatically suppressed BC cell proliferation in vitro and in vivo, induced G0/G1 arrest, and promoted apoptosis. We subsequently identified the oncogene PIM-1 as a direct target of miR-486-5p in BC. Overexpression of PIM-1 attenuated the function of miR-486-5p in BC cells. Together, we conclude that miR-486-5p exerts its antiproliferative function by directly downregulating PIM-1 expression. This novel miR-486-5p/PIM-1 axis provides insight into the pathogenesis of BC and might be therapeutic targets for prevention or treatment of BC.
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Affiliation(s)
- Guoqiang Zhang
- Department of Thyroid and Breast Surgery, Affiliated Hospital of Binzhou Medical College, Binzhou, 256603, China
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van der Meer R, Song HY, Park SH, Abdulkadir SA, Roh M. RNAi screen identifies a synthetic lethal interaction between PIM1 overexpression and PLK1 inhibition. Clin Cancer Res 2014; 20:3211-21. [PMID: 24771642 PMCID: PMC4086184 DOI: 10.1158/1078-0432.ccr-13-3116] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE To identify genes whose depletion is detrimental to Pim1-overexpressing prostate cancer cells and to validate this finding in vitro and in vivo. EXPERIMENTAL DESIGN RNAi screening was used to identify genes whose depletion is detrimental to Pim1-overexpressing cells. Our finding was validated using shRNA or PLK1-specific inhibitor BI 2536. Xenograft studies were performed using both PLK1-knockdown cells and BI 2536 to investigate the effects of PLK1 inhibition on tumorigenesis in Pim1-overexpressing cells. Finally, PLK1 and PIM1 expression patterns in human prostate tumors were examined by immunohistochemistry using tissue microarrays. RESULTS We identified the mitotic regulator polo-like kinase (PLK1) as a gene whose depletion is particularly detrimental to the viability of Pim1-overexpressing prostate cancer. Inhibition of PLK1 by shRNA or BI 2536 in Pim1-overexpressing prostate cancer xenograft models resulted in a dramatic inhibition of tumor progression. Notably, Pim1-overexpressing cells were more prone to mitotic arrest followed by apoptosis due to PLK1 inhibition than control cells. Furthermore, inhibition of PLK1 led to the reduction of MYC protein levels both in vitro and in vivo. Our data also suggest that PIM1 and PLK1 physically interact and PIM1 might phosphorylate PLK1. Finally, PLK1 and PIM1 are frequently co-expressed in human prostate tumors, and co-expression of PLK1 and PIM1 was significantly correlated to higher Gleason grades. CONCLUSIONS Our findings demonstrate that PIM1-overexpressing cancer cells are particularly sensitive to PLK1 inhibition, suggesting that PIM1 might be used as a marker for identifying patients who will benefit from PLK1 inhibitor treatment.
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Affiliation(s)
- Riet van der Meer
- Authors' Affiliations: Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee; and Department of Radiation Oncology, Northwestern Feinberg School of Medicine, Chicago, Illinois
| | - Ha Yong Song
- Authors' Affiliations: Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee; and Department of Radiation Oncology, Northwestern Feinberg School of Medicine, Chicago, Illinois
| | - Seong-Hoon Park
- Authors' Affiliations: Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee; and Department of Radiation Oncology, Northwestern Feinberg School of Medicine, Chicago, Illinois
| | - Sarki A Abdulkadir
- Authors' Affiliations: Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee; and Department of Radiation Oncology, Northwestern Feinberg School of Medicine, Chicago, Illinois
| | - Meejeon Roh
- Authors' Affiliations: Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee; and Department of Radiation Oncology, Northwestern Feinberg School of Medicine, Chicago, Illinois
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11
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Ikawa-Yoshida A, Ando K, Oki E, Saeki H, Kumashiro R, Taketani K, Ida S, Tokunaga E, Kitao H, Morita M, Maehara Y. Contribution of BubR1 to oxidative stress-induced aneuploidy in p53-deficient cells. Cancer Med 2013; 2:447-56. [PMID: 24156017 PMCID: PMC3799279 DOI: 10.1002/cam4.101] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Revised: 04/22/2013] [Accepted: 05/02/2013] [Indexed: 12/23/2022] Open
Abstract
DNA aneuploidy is observed in various human tumors and is associated with the abnormal expression of spindle assembly checkpoint (SAC) proteins. Oxidative stress (OS) causes DNA damage and chromosome instability that may lead to carcinogenesis. OS is also suggested to contribute to an increase in aneuploid cells. However, it is not clear how OS is involved in the regulation of SAC and contributes to carcinogenesis associated with aneuploidy. Here we show that an oxidant (KBrO3) activated the p53 signaling pathway and suppressed the expression of SAC factors, BubR1, and Mad2, in human diploid fibroblast MRC5 cells. This suppression was dependent on functional p53 and reactive oxygen species. In p53 knockdown cells, KBrO3 did not suppress BubR1 and Mad2 expression and increased both binucleated cells and cells with >4N DNA content. BubR1 and not Mad2 downregulation suppressed KBrO3-induced binucleated cells and cells with >4N DNA content in p53 knockdown cells, suggesting that BubR1 contributes to enhanced polyploidization by a mechanism other than its SAC function. In analysis of 182 gastric cancer specimens, we found that BubR1 expression was significantly high when p53 was positively stained, which indicates loss of p53 function (P = 0.0019). Moreover, positive staining of p53 and high expression of BubR1 in tumors were significantly correlated with DNA aneuploidy (P = 0.0065). These observations suggest that p53 deficiency may lead to the failure of BubR1 downregulation by OS and that p53 deficiency and BubR1 accumulation could contribute to gastric carcinogenesis associated with aneuploidy. We found that OS could contribute to the emergence of polyploid cells when p53 was deficient in normal human fibroblast cells. Importantly, this polyploidization could be suppressed by downregulating the expression of one spindle assembly checkpoint factor, BubR1. We also found that p53 dysfunction and BubR1 accumulation strongly correlate with the extent of aneuploidy in gastric cancer specimen and our data suggest that p53 deficiency and BubR1 accumulation could contribute to gastric carcinogenesis associated with aneuploidy.
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Affiliation(s)
- Ayae Ikawa-Yoshida
- Departments of Surgery and Science Graduate School of Medical Sciences, Kyushu University Fukuoka, Japan
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Potential role of meiosis proteins in melanoma chromosomal instability. J Skin Cancer 2013; 2013:190109. [PMID: 23840955 PMCID: PMC3694528 DOI: 10.1155/2013/190109] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Accepted: 05/21/2013] [Indexed: 12/05/2022] Open
Abstract
Melanomas demonstrate chromosomal instability (CIN). In fact, CIN can be used to differentiate melanoma from benign nevi. The exact molecular mechanisms that drive CIN in melanoma have yet to be fully elucidated. Cancer/testis antigens are a unique group of germ cell proteins that are found to be primarily expressed in melanoma as compared to benign nevi. The abnormal expression of these germ cell proteins, normally expected only in the testis and ovaries, in somatic cells may lead to interference with normal cellular pathways. Germ cell proteins that may be particularly critical in CIN are meiosis proteins. Here, we review pathways unique to meiosis with a focus on how the aberrant expression of meiosis proteins in normal mitotic cells “meiomitosis” could impact chromosomal instability in melanoma and other cancers.
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Rahim S, Uren A. Emergence of ETS transcription factors as diagnostic tools and therapeutic targets in prostate cancer. Am J Transl Res 2013; 5:254-268. [PMID: 23634237 PMCID: PMC3633969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 04/05/2013] [Indexed: 06/02/2023]
Abstract
The discovery of chromosomal translocations in prostate cancer has greatly enhanced our understanding of prostate cancer biology. Genomic rearrangements involving the ETS family of transcription factors are estimated to be present in 50-70% of prostate cancer cases. These rearrangements fuse the ETS factors with promoters of genes that are androgen regulated. Thus, the expression of ETS factors, such as ERG, ETV1, ETV4 and ETV5, is mediated by androgen. In-vitro and in-vivo studies suggest that overexpression of ETS proteins increase cell proliferation and confer an invasive phenotype to prostate cancer cells. Epidemiological studies demonstrate that ETS-fusion positive patients exhibit tumors corresponding to a more advanced disease. The ability of ETS factors to serve as markers for screening and diagnosing prostate cancer patients is being investigated, and the results have been largely positive to date. Additionally, ETS factors present an excellent opportunity as therapeutic targets and several strategies have been devised to directly target ETS proteins or their binding partners and downstream effectors.
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Affiliation(s)
- Said Rahim
- Lombardi Comprehensive Cancer Center, Georgetown University Washington DC
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14
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Foster BA, Gangavarapu KJ, Mathew G, Azabdaftari G, Morrison CD, Miller A, Huss WJ. Human prostate side population cells demonstrate stem cell properties in recombination with urogenital sinus mesenchyme. PLoS One 2013; 8:e55062. [PMID: 23383057 PMCID: PMC3561453 DOI: 10.1371/journal.pone.0055062] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Accepted: 12/22/2012] [Indexed: 01/07/2023] Open
Abstract
Stem cell enrichment provides a tool to examine prostate stem cells obtained from benign and malignant tissue. Functional assays can enrich stem cells based on common stem cell phenotypes, such as high ATP binding cassette (ABC) transporter mediated efflux of Hoechst substrates (side population assay). This functional assay is based upon mechanisms that protect cells from environmental insult thus contributing to the survival and protection of the stem cell population. We have isolated and analyzed cells digested from twelve clinical prostate specimens based on the side population assay. Prostate stem cell properties of the isolated cells were tested by serial recombination with rat urogenital mesenchyme. Recombinants with side population cells demonstrate an increase in the frequency of human ductal growth and the number of glands per recombinant when compared to recombinants with non-side population cells. Isolated cells were capable of prostatic growth for up to three generations in the recombination assay with as little as 125 sorted prostate cells. The ability to reproducibly use cells isolated by fluorescence activated cell sorting from human prostate tissue is an essential step to a better understanding of human prostate stem cell biology. ABC transporter G2 (ABCG2) was expressed in recombinants from side population cells indicating the side population cells have self-renewal properties. Epithelial cell differentiation of recombinants was determined by immunohistochemical analysis for expression of the basal, luminal, and neuroendocrine markers, p63, androgen receptor, prostate specific antigen, and chromogranin A, respectively. Thus, the ABCG2 expressing side population demonstrates multipotency and self-renewal properties indicating stem cells are within this population.
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Affiliation(s)
- Barbara A Foster
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, NY, USA
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15
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Diagnostic role of chromosomal instability in melanoma. J Skin Cancer 2012; 2012:914267. [PMID: 23125934 PMCID: PMC3483783 DOI: 10.1155/2012/914267] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Revised: 09/20/2012] [Accepted: 09/21/2012] [Indexed: 02/03/2023] Open
Abstract
Early diagnosis gives melanoma patients the best chance for long term survival. However discrimination of an early melanoma from an unusual/atypical benign nevus can represent a significant challenge. There are no current pathological markers to definitively define malignant potential in these indeterminate lesions. Thus, there is a need for improved diagnostic tools. Chromosomal instability (CIN) is a hallmark of cancer and is markedly prevalent in melanoma. Advances in genomics have opened the door for the development of molecular tools to better segregate benign and malignant lesions. This paper focuses on CIN in melanoma and the role of current diagnostic approaches.
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Trichomonosis, a common curable STI, and prostate carcinogenesis--a proposed molecular mechanism. PLoS Pathog 2012; 8:e1002801. [PMID: 22912571 PMCID: PMC3415452 DOI: 10.1371/journal.ppat.1002801] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
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17
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Abstract
Emerging evidence suggests that chromatin adopts a nonrandom 3D topology and that the organization of genes into structural hubs and domains affects their transcriptional status. How chromatin conformation changes in diseases such as cancer is poorly understood. Moreover, how oncogenic transcription factors, which bind to thousands of sites across the genome, influence gene regulation by globally altering the topology of chromatin requires further investigation. To address these questions, we performed unbiased high-resolution mapping of intra- and interchromosome interactions upon overexpression of ERG, an oncogenic transcription factor frequently overexpressed in prostate cancer as a result of a gene fusion. By integrating data from genome-wide chromosome conformation capture (Hi-C), ERG binding, and gene expression, we demonstrate that oncogenic transcription factor overexpression is associated with global, reproducible, and functionally coherent changes in chromatin organization. The results presented here have broader implications, as genomic alterations in other cancer types frequently give rise to aberrant transcription factor expression, e.g., EWS-FLI1, c-Myc, n-Myc, and PML-RARα.
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Chakraborty A, Bodipati N, Demonacos MK, Peddinti R, Ghosh K, Roy P. Long term induction by pterostilbene results in autophagy and cellular differentiation in MCF-7 cells via ROS dependent pathway. Mol Cell Endocrinol 2012; 355:25-40. [PMID: 22273805 DOI: 10.1016/j.mce.2012.01.009] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Revised: 12/20/2011] [Accepted: 01/10/2012] [Indexed: 01/28/2023]
Abstract
This study shows the effect of pterostilbene on intracellular neutral lipid accumulation in MCF-7 breast cancer cells leading to growth arrest and autophagy. On exposing the breast cancer cells with 30 μM pterostilbene for 72 h there was almost 2-folds increase in neutral lipids and triglycerides. Also the phytochemical caused a 4-folds increase in the expression of adipogenic differentiation marker c/EBPα. Further, pterostilbene inhibited 3β-hydroxylsterol-Δ(7)-reductase, the enzyme which catalyzes the last step conversion of 7-dehydrocholesterol to cholesterol, and thereby causes the intracellular accumulation of the former sterol. These results were associated with over-expression of oxysterol binding protein homologue and liver X receptor (LXR) by ~7-folds. Pterostilbene also caused a simultaneous increase in the expression autophagic marker proteins Beclin 1 and LC3 II (microtubule-associated protein 1 light chain 3) by approximately 6-folds, which leads to an alternative pathway of autophagy. These effects were observed in association with the loss of mitotic and metastatic potential of MCF-7 cells which was abolished in the presence of catalase (ROS scavenger) or 3MA (autophagic inhibitor). Thus the present data shows that the long term exposure to pterostilbene causes growth arrest in MCF-7 cells which may be due to differentiation of the mammary carcinoma cells into normal epithelial cell like morphology and activation of autophagy.
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Affiliation(s)
- Ajanta Chakraborty
- Molecular Endocrinology Laboratory, Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee 247 667, Uttarakhand, India
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Yan B, Yau EX, Samanta S, Ong CW, Yong KJ, Ng LK, Bhattacharya B, Lim KH, Soong R, Yeoh KG, Deng N, Tan P, Lam Y, Salto-Tellez M. Clinical and therapeutic relevance of PIM1 kinase in gastric cancer. Gastric Cancer 2012; 15:188-97. [PMID: 21993851 DOI: 10.1007/s10120-011-0097-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Accepted: 09/11/2011] [Indexed: 02/07/2023]
Abstract
BACKGROUND Gastric cancer is a leading cause of cancer-related mortality, and chemotherapeutic options are currently limited. PIM1 kinase, an oncogene that promotes tumorigenesis in several cancer types, might represent a novel therapeutic target in gastric cancer. METHODS We studied the expression and genomic status of PIM1 in human primary gastric normal and tumor tissue samples by immunohistochemistry and array-based comparative genomic hybridization (aCGH). To ascertain whether PIM1 expression predicted susceptibility to PIM1 kinase-specific inhibition, the cytotoxic effect of a previously reported PIM1-specific small molecular inhibitor (K00135) was investigated in two gastric cancer cell lines with high (IM95) and undetectable (NUGC-4) PIM1 expression levels. RESULTS PIM1 expression was exclusively nuclear in normal gastric epithelial cells, while aberrant expression/localization (decreased nuclear and/or increased cytoplasmic expression) was observed in 75.6% (68/90) of the human gastric cancer tissue samples, with a significant inverse correlation between nuclear and cytoplasmic expression levels. Clinicopathological analyses revealed that decreased nuclear PIM1 expression correlated with poorer survival and greater depth of tumor invasion, while increased cytoplasmic PIM1 expression correlated inversely with the presence of lymphovascular invasion. High-level PIM1 amplification was identified in 10.5% of gastric cancers by aCGH. K00135 impaired the survival of IM95, while it had no significant effect on NUGC-4 survival. CONCLUSION Our findings demonstrate the clinical and therapeutic relevance of PIM1 in gastric cancers, and suggest that PIM1 represents a potential therapeutic target.
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Affiliation(s)
- Benedict Yan
- Department of Pathology, National University Health System, National University of Singapore, 5 Lower Kent Ridge Road, Singapore 119074, Singapore.
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20
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Roh M, van der Meer R, Abdulkadir SA. Tumorigenic polyploid cells contain elevated ROS and ARE selectively targeted by antioxidant treatment. J Cell Physiol 2012; 227:801-12. [PMID: 21503880 DOI: 10.1002/jcp.22793] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Polyploidy has been linked to tumorigenicity mainly due to the chromosomal aberrations. Elevated reactive oxygen species (ROS) generation, on the other hand, has also been associated with oncogenic transformation in most cancer cells. However, a possible link between ploidy and ROS is largely unexplored. Here we have examined the role of ROS in the tumorigenicity of polyploid cells. We show that polyploid prostate and mammary epithelial cells contain higher levels of ROS due to their higher mitochondrial contents. ROS levels and mitochondrial mass are also higher in dihydrocytochalasin B (DCB)-induced polyploid cells, suggesting that higher levels of ROS observed in polyploid cell can occur due to cytokinesis failure. Interestingly, polyploid cells were more sensitive to the inhibitory effect of the antioxidant, N-Acetyl-L-cysteine (NAC), than control diploid cells. Treatment of polyploid/diploid cells with NAC led to the selective elimination of polyploid cells over time and abrogated the tumorigenicity of polyploid cells. This effect was partially mediated via the Akt signaling pathway. We next explored a possible role for ROS in promoting chromosomal instability by analyzing the effects of ROS on the mitotic stage of the cell cycle. Enhancing ROS levels by treating cells with hydrogen peroxide delayed not only entry into and but also exit from mitosis. Furthermore, increasing ROS levels significantly increased taxol resistance. Our results indicated that increased ROS in polyploid cells can contribute to tumorigenicity and highlight the therapeutic potential of antioxidants by selectively targeting the tumorigenic polyploid cells and by reversing taxol resistance.
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Affiliation(s)
- Meejeon Roh
- Department of Pathology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.
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21
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Magistroni V, Mologni L, Sanselicio S, Reid JF, Redaelli S, Piazza R, Viltadi M, Bovo G, Strada G, Grasso M, Gariboldi M, Gambacorti-Passerini C. ERG deregulation induces PIM1 over-expression and aneuploidy in prostate epithelial cells. PLoS One 2011; 6:e28162. [PMID: 22140532 PMCID: PMC3227636 DOI: 10.1371/journal.pone.0028162] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Accepted: 11/02/2011] [Indexed: 12/19/2022] Open
Abstract
The ERG gene belongs to the ETS family of transcription factors and has been found to be involved in atypical chromosomal rearrangements in several cancers. To gain insight into the oncogenic activity of ERG, we compared the gene expression profile of NIH-3T3 cells stably expressing the coding regions of the three main ERG oncogenic fusions: TMPRSS2/ERG (tERG), EWS/ERG and FUS/ERG. We found that all three ERG fusions significantly up-regulate PIM1 expression in the NIH-3T3 cell line. PIM1 is a serine/threonine kinase frequently over-expressed in cancers of haematological and epithelial origin. We show here that tERG expression induces PIM1 in the non-malignant prostate cell line RWPE-1, strengthening the relation between tERG and PIM1 up-regulation in the initial stages of prostate carcinogenesis. Silencing of tERG reversed PIM1 induction. A significant association between ERG and PIM1 expression in clinical prostate carcinoma specimens was found, suggesting that such a mechanism may be relevant in vivo. Chromatin Immunoprecipitation experiments showed that tERG directly binds to PIM1 promoter in the RWPE-1 prostate cell line, suggesting that tERG could be a direct regulator of PIM1 expression. The up-regulation of PIM1 induced by tERG over-expression significantly modified Cyclin B1 levels and increased the percentage of aneuploid cells in the RWPE-1 cell line after taxane-based treatment. Here we provide the first evidence for an ERG-mediated PIM1 up-regulation in prostate cells in vitro and in vivo, suggesting a direct effect of ERG transcriptional activity in the alteration of genetic stability.
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Affiliation(s)
- Vera Magistroni
- Department of Clinical Medicine, University of Milano-Bicocca, Monza, Italy.
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22
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Euhus D, Bu D, Xie XJ, Sarode V, Ashfaq R, Hunt K, Xia W, O'Shaughnessy J, Grant M, Arun B, Dooley W, Miller A, Flockhart D, Lewis C. Tamoxifen downregulates ets oncogene family members ETV4 and ETV5 in benign breast tissue: implications for durable risk reduction. Cancer Prev Res (Phila) 2011; 4:1852-62. [PMID: 21778330 PMCID: PMC3208724 DOI: 10.1158/1940-6207.capr-11-0186] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Five years of tamoxifen reduces breast cancer risk by nearly 50% but is associated with significant side effects and toxicities. A better understanding of the direct and indirect effects of tamoxifen in benign breast tissue could elucidate new mechanisms of breast carcinogenesis, suggest novel chemoprevention targets, and provide relevant early response biomarkers for phase II prevention trials. Seventy-three women at increased risk for breast cancer were randomized to tamoxifen (20 mg daily) or placebo for 3 months. Blood and breast tissue samples were collected at baseline and posttreatment. Sixty-nine women completed all study activities (37 tamoxifen and 32 placebo). The selected biomarkers focused on estradiol and IGFs in the blood; DNA methylation and cytology in random periareolar fine-needle aspirates; and tissue morphometry, proliferation, apoptosis, and gene expression (microarray and reverse transcriptase PCR) in the tissue core samples. Tamoxifen downregulated Ets oncogene transcription factor family members ETV4 and ETV5 and reduced breast epithelial cell proliferation independent of CYP2D6 genotypes or effects on estradiol, ESR1, or IGFs. Reduction in proliferation was correlated with downregulation of ETV4 and DNAJC12. Tamoxifen reduced the expression of ETV4- and ETV5-regulated genes implicated in epithelial-stromal interaction and tissue remodeling. Three months of tamoxifen did not affect breast tissue composition, cytologic atypia, preneoplasia, or apoptosis. A plausible mechanism for the chemopreventive effects of tamoxifen is restriction of lobular expansion into stroma through downregulation of ETV4 and ETV5. The human equivalent of murine multipotential progenitor cap cells of terminal end buds may be the primary target.
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Affiliation(s)
- David Euhus
- Department of Surgery, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390, USA.
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23
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Okamoto R, Delansorne R, Wakimoto N, Doan NB, Akagi T, Shen M, Ho QH, Said JW, Koeffler HP. Inecalcitol, an analog of 1α,25(OH)(2) D(3) , induces growth arrest of androgen-dependent prostate cancer cells. Int J Cancer 2011; 130:2464-73. [PMID: 21732345 DOI: 10.1002/ijc.26279] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Accepted: 06/07/2011] [Indexed: 11/05/2022]
Abstract
19-nor-14-epi-23-yne-1,25(OH)(2) D(3) (inecalcitol) is a unique vitamin D(3) analog. We evaluated the activity of inecalcitol in a human prostate cancer model system. The analog was 11-fold more potent than 1,25(OH)(2) D(3) in causing 50% clonal growth inhibition of androgen-sensitive human prostate cancer LNCaP cells. Inecalcitol, more than 1,25(OH)(2) D(3) , reduced in a dose-dependent manner the expression levels of the transcription factor ETS variant 1 and the serine/threonine protein kinase Pim-1, both of which are upregulated in prostate cancer. Remarkably, dose challenge experiments revealed that inecalcitol maximal tolerated dose (MTD) by intraperitoneal (i.p.) administration was 30 μg/mouse (1,300 μg/kg) three times per week, while we previously found that the MTD of 1,25(OH)(2) D(3) is 0.0625 μg/mouse; therefore, inecalcitol is 480 times less hypercalcemic than 1,25(OH)(2) D(3) . Pharmacokinetic studies showed that plasma half-life of inecalcitol were 18.3 min in mice. A xenograft model of LNCaP cells was developed in immunodeficient mice treated with inecalcitol. The tumors of the diluent-treated control mice increased in size but those in the inecalcitol treatment group did not grow. Our data suggest that inecalcitol inhibits androgen-responsive prostate cancer growth in vivo and should be examined either alone or with other chemotherapy in clinical trials in individuals with rising serum prostate-specific antigen after receiving either surgery or irradiation therapy with curative intent.
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24
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Magnuson NS, Wang Z, Ding G, Reeves R. Why target PIM1 for cancer diagnosis and treatment? Future Oncol 2011; 6:1461-78. [PMID: 20919829 DOI: 10.2217/fon.10.106] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The highly conserved proto-oncogenic protein PIM1 is an unusual serine or threonine kinase, in part because it is constitutively active. Overexpression of PIM1 experimentally leads to tumor formation in mice, while complete knockout of the protein has no observable phenotype. It appears to contribute to cancer development in three major ways when it is overexpressed; by inhibiting apoptosis, by promoting cell proliferation and by promoting genomic instability. Expression in normal tissues is nearly undetectable. However, in hematopoietic malignancies and in a variety of solid tumors, increased PIM1 expression has been shown to correlate with the stage of disease. This characteristic suggests it can serve as a useful biomarker for cancer diagnosis and prognosis. Several specific and potent inhibitors of PIM1’s kinase activity have also been shown to induce apoptotic death of cancer cells, to sensitize cancer cells to chemotherapy and to synergize with other anti-tumor agents, thus making it an attractive therapeutic target.
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Affiliation(s)
- Nancy S Magnuson
- School of Molecular Biosciences, Washington State University, Pullman, WA 99164–7520, USA
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25
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Vitale I, Galluzzi L, Senovilla L, Criollo A, Jemaà M, Castedo M, Kroemer G. Illicit survival of cancer cells during polyploidization and depolyploidization. Cell Death Differ 2010; 18:1403-13. [PMID: 21072053 DOI: 10.1038/cdd.2010.145] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Tetraploidy and the depolyploidization of tetraploid cells may contribute to oncogenesis. Several mechanisms have evolved to avoid the generation, survival, proliferation and depolyploidization of tetraploids. Cells that illicitly survive these checkpoints are prone to chromosomal instability and aneuploidization. Along with their replication, tetraploids constantly undergo chromosomal rearrangements that eventually lead to pseudodiploidy by two non-exclusive mechanisms: (i) multipolar divisions and (ii) illicit bipolar divisions in the presence of improper microtubule-kinetochore attachments. Here, we describe the regulation and the molecular mechanisms that underlie such a 'polyploidization-depolyploidization' cascade, while focusing on the role of oncogenes and tumor suppressor genes in tetraploidy-driven tumorigenesis. We speculate that the identification of signaling/metabolic cascades that are required for the survival of tetraploid or aneuploid (but not diploid) cancer cells may pave the way for the development of novel broad-spectrum anticancer agents.
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26
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Meyer SE, Peace BE, Bahassi EM, Kavanaugh GM, Wagh PK, Robbins SB, Yin M, Wells SI, Zinser GM, Stambrook PJ, Waltz SE. Chk2*1100delC Acts in synergy with the Ron receptor tyrosine kinase to accelerate mammary tumorigenesis in mice. Cancer Lett 2010; 296:186-93. [PMID: 20434834 DOI: 10.1016/j.canlet.2010.04.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2009] [Revised: 03/31/2010] [Accepted: 04/06/2010] [Indexed: 01/01/2023]
Abstract
The CHEK2 (Chk2 in mice) polymorphic variant, CHEK2*1100delC, leads to genomic instability and is associated with an increased risk for breast cancer. The Ron receptor tyrosine kinase is overexpressed in a large fraction of human breast cancers. Here, we asked whether the low penetrance Chk2*1100delC allele alters the tumorigenic efficacy of Ron in the development of mammary tumors in a mouse model. Our data demonstrate that Ron overexpression on a Chk2*1100delC background accelerates the development of mammary tumors, and shows that pathways mediated by a tyrosine kinase receptor and a regulator of the cell cycle can act to hasten tumorigenesis in vivo.
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Affiliation(s)
- Sara E Meyer
- Department of Cancer and Cell Biology, University of Cincinnati College of Medicine, OH 45267, USA
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27
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Zemskova M, Lilly MB, Lin YW, Song JH, Kraft AS. p53-dependent induction of prostate cancer cell senescence by the PIM1 protein kinase. Mol Cancer Res 2010; 8:1126-41. [PMID: 20647331 DOI: 10.1158/1541-7786.mcr-10-0174] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The PIM family of serine threonine protein kinases plays an important role in regulating both the growth and transformation of malignant cells. However, in a cell line-dependent manner, overexpression of PIM1 can inhibit cell and tumor growth. In 22Rv1 human prostate cells, but not in Du145 or RWPE-2, PIM1 overexpression was associated with marked increases in cellular senescence, as shown by changes in the levels of beta-galactosidase (SA-beta-Gal), p21, interleukin (IL)-6 and IL-8 mRNA and protein. During early cell passages, PIM1 induced cellular polyploidy. As the passage number increased, markers of DNA damage, including the level of gammaH2AX and CHK2 phosphorylation, were seen. Coincident with these DNA damage markers, the level of p53 protein and genes transcriptionally activated by p53, such as p21, TP53INP1, and DDIT4, increased. In these 22Rv1 cells, the induction of p53 protein was associated not only with senescence but also with a significant level of apoptosis. The importance of the p53 pathway to PIM1-driven cellular senescence was further shown by the observation that expression of dominant-negative p53 or shRNA targeting p21 blocked the PIM1-induced changes in the DNA damage response and increases in SA-beta-Gal activity. Likewise, in a subcutaneous tumor model, PIM1-induced senescence was rescued when the p53-p21 pathways are inactivated. Based on these results, PIM1 will have its most profound effects on tumorigenesis in situations where the senescence response is inactivated.
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Affiliation(s)
- Marina Zemskova
- Department of Cell and Molecular Pharmacology, Hollings Cancer Center, Charleston, SC 29425, USA
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28
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Wang Y, Jha AK, Chen R, Doonan JH, Yang M. Polyploidy-associated genomic instability in Arabidopsis thaliana. Genesis 2010; 48:254-63. [PMID: 20143347 DOI: 10.1002/dvg.20610] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Formation of polyploid organisms by fertilization of unreduced gametes in meiotic mutants is believed to be a common phenomenon in species evolution. However, not well understood is how species in nature generally exist as haploid and diploid organisms in a long evolutionary time while polyploidization must have repeatedly occurred via meiotic mutations. Here, we show that the ploidy increased for two consecutive generations due to unreduced but viable gametes in the Arabidopsis cyclin a1;2-2 (also named tardy asynchronous meiosis-2) mutant, but the resultant octaploid plants produced progeny of either the same or reduced ploidy via genomic reductions during meiosis and pollen mitosis. Ploidy reductions through sexual reproduction were also observed in independently generated artificial octaploid and hexaploid Arabidopsis plants. These results demonstrate that octaploid is likely the maximal ploidy produced through sexual reproduction in Arabidopsis. The polyploidy-associated genomic instability may be a general phenomenon that constrains ploidy levels in species evolution.
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Affiliation(s)
- Yixing Wang
- Department of Botany, Oklahoma State University, Stillwater, Oklahoma 74078, USA
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Kim J, Roh M, Abdulkadir SA. Pim1 promotes human prostate cancer cell tumorigenicity and c-MYC transcriptional activity. BMC Cancer 2010; 10:248. [PMID: 20515470 PMCID: PMC2886047 DOI: 10.1186/1471-2407-10-248] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2009] [Accepted: 06/01/2010] [Indexed: 01/02/2023] Open
Abstract
Background The serine/threonine kinase PIM1 has been implicated as an oncogene in various human cancers including lymphomas, gastric, colorectal and prostate carcinomas. In mouse models, Pim1 is known to cooperate with c-Myc to promote tumorigenicity. However, there has been limited analysis of the tumorigenic potential of Pim1 overexpression in benign and malignant human prostate cancer cells in vivo. Methods We overexpressed Pim1 in three human prostate cell lines representing different disease stages including benign (RWPE1), androgen-dependent cancer (LNCaP) and androgen-independent cancer (DU145). We then analyzed in vitro and in vivo tumorigenicity as well as the effect of Pim1 overexpression on c-MYC transcriptional activity by reporter assays and gene expression profiling using an inducible MYC-ER system. To validate that Pim1 induces tumorigenicity and target gene expression by modulating c-MYC transcriptional activity, we inhibited c-MYC using a small molecule inhibitor (10058-F4) or RNA interference. Results Overexpression of Pim1 alone was not sufficient to convert the benign RWPE1 cell to malignancy although it enhanced their proliferation rates when grown as xenografts in vivo. However, Pim1 expression enhanced the in vitro and in vivo tumorigenic potentials of the human prostate cancer cell lines LNCaP and DU145. Reporter assays revealed increased c-MYC transcriptional activity in Pim1-expressing cells and mRNA expression profiling demonstrated that a large fraction of c-MYC target genes were also regulated by Pim1 expression. The c-MYC inhibitor 10058-F4 suppressed the tumorigenicity of Pim1-expressing prostate cancer cells. Interestingly, 10058-F4 treatment also led to a reduction of Pim1 protein but not mRNA. Knocking-down c-MYC using short hairpin RNA reversed the effects of Pim1 on Pim1/MYC target genes. Conclusion Our results suggest an in vivo role of Pim1 in promoting prostate tumorigenesis although it displayed distinct oncogenic activities depending on the disease stage of the cell line. Pim1 promotes tumorigenicity at least in part by enhancing c-MYC transcriptional activity. We also made the novel discovery that treatment of cells with the c-MYC inhibitor 10058-F4 leads to a reduction in Pim1 protein levels.
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Affiliation(s)
- Jongchan Kim
- Department of Pathology, Vanderbilt University Medical Center, Nashville, TN, USA
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Jiang M, Strand DW, Fernandez S, He Y, Yi Y, Birbach A, Qiu Q, Schmid J, Tang DG, Hayward SW. Functional remodeling of benign human prostatic tissues in vivo by spontaneously immortalized progenitor and intermediate cells. Stem Cells 2010; 28:344-56. [PMID: 20020426 PMCID: PMC2962907 DOI: 10.1002/stem.284] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Tissue remodeling or regeneration is believed to initiate from multipotent stem and progenitor cells. We report here the establishment of two spontaneously immortalized adult non-tumorigenic human prostate epithelial cell lines, NHPrE1 and BHPrE1. NHPrE1 (CD133(high)/CD44(high)/OCT4(high)/PTEN(high)) was characterized as a putative progenitor cell, and BHPrE1 (p63(high)/p53(high)/p21(WAF1)(high)/RB(high)) was characterized as a putative epithelial intermediate cell. Genomic analysis demonstrated an abnormal karyotype with genomic rearrangements including PTEN amplification in NHPrE1 and CTNNB1 (beta-catenin) amplification in BHPrE1 cells. Embedded three-dimensional culture of NHPrE1 showed greater branching than BHPrE1. A tissue recombination-xenografting model was utilized to compare remodeling of human prostatic tissues in vivo. A series of tissue recombinants, made by mixing different ratios of human prostatic epithelial cells and inductive rat urogenital sinus mesenchyme, were grafted to the renal capsule of severe combined immunodeficient mice. Both cell lines were able to regenerate benign secretory ductal-acinar architecture in vivo, containing intact basal and luminal epithelial layers confirmed by the expression of appropriate CK profiles. Prostate-specific antigen, 15-lipoxygenase-2, androgen receptor, and NKX3.1 proteins were appropriately expressed in the regenerated epithelia. Regeneration of benign prostatic glandular structures could be achieved using as few as 10 NHPrE1 cells, whereas 200,000 BHPrE1 cells were required to achieve prostatic architecture. This suggests a greater proportion of progenitor/stem cells in NHPrE1 than in BHPrE1. These cell lines provide important data on progenitor and intermediate cell phenotypes and represent significant new tools for the elucidation of molecular mechanisms of human prostatic regeneration, pathogenesis, and carcinogenesis.
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Affiliation(s)
- Ming Jiang
- Department of Urological Surgery, Vanderbilt University Medical Center and Vanderbilt-Ingram Cancer Center, Nashville, Tennessee 37232-2765, USA.
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Wang J, Kim J, Roh M, Franco OE, Hayward SW, Wills ML, Abdulkadir SA. Pim1 kinase synergizes with c-MYC to induce advanced prostate carcinoma. Oncogene 2010; 29:2477-87. [PMID: 20140016 PMCID: PMC2861731 DOI: 10.1038/onc.2010.10] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The oncogenic PIM1 kinase has been implicated as a cofactor for c-MYC in prostate carcinogenesis. In this study, we show that in human prostate tumors, coexpression of c-MYC and PIM1 is associated with higher Gleason grades. Using a tissue recombination model coupled with lentiviral-mediated gene transfer we find that Pim1 is weakly oncogenic in naive adult mouse prostatic epithelium. However, it cooperates dramatically with c-MYC to induce prostate cancer within 6-weeks. Importantly, c-MYC/Pim1 synergy is critically dependent on Pim1 kinase activity. c-MYC/Pim1 tumors showed increased levels of the active serine-62 (S62) phosphorylated form of c-MYC. Grafts expressing a phosphomimetic c-MYCS62D mutant had higher rates of proliferation than grafts expressing wild type c-MYC but did not form tumors like c-MYC/Pim1 grafts, indicating that Pim1 cooperativity with c-MYC in vivo involves additional mechanisms other than enhancement of c-MYC activity by S62 phosphorylation. c-MYC/Pim1-induced prostate carcinomas show evidence of neuroendocrine (NE) differentiation. Additional studies, including the identification of tumor cells coexpressing androgen receptor and NE cell markers synaptophysin and Ascl1 suggested that NE tumors arose from adenocarcinoma cells through transdifferentiation. These results directly show functional cooperativity between c-MYC and PIM1 in prostate tumorigenesis in vivo and support efforts for targeting PIM1 in prostate cancer.
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Affiliation(s)
- J Wang
- Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
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Dalton WB, Yang VW. Role of prolonged mitotic checkpoint activation in the formation and treatment of cancer. Future Oncol 2009; 5:1363-70. [PMID: 19903065 PMCID: PMC2791162 DOI: 10.2217/fon.09.118] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Mitotic abnormalities are a common feature of human cancer cells, and recent studies have provided evidence that such abnormalities may play a causative, rather than merely incidental role, in tumorigenesis. One such abnormality is prolonged activation of the mitotic checkpoint, which can be provoked by a number of the gene changes that drive tumor formation. At the same time, antimitotic chemotherapeutics exert their clinical efficacy through the large-scale induction of prolonged mitotic checkpoint activation, indicating that mitotic arrest is influential in both the formation and treatment of human cancer. However, how this influence occurs is not well understood. In this perspective, we will discuss the current evidence in support of the potential mechanisms by which prolonged activation of the mitotic checkpoint affects both tumorigenesis and antimitotic chemotherapy.
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Affiliation(s)
- W. Brian Dalton
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, U. S. A
| | - Vincent W. Yang
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, U. S. A
- Department of Hematology and Medical Oncology, Emory University School of Medicine, Atlanta, Georgia, U. S. A
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Abstract
Precise control of centrosome number is crucial for bipolar spindle assembly and accurate transmission of genetic material to daughter cells. Failure to properly control centrosome number results in supernumerary centrosomes, which are frequently found in cancer cells. This presents a paradox: during mitosis, cells with more than two centrosomes are prone to multipolar mitoses and cell death, however, cancer cells possessing extra centrosomes usually divide successfully. One mechanism frequently utilized by cancer cells to escape death caused by multipolar mitoses is the clustering of supernumerary centrosomes into bipolar arrays. An understanding of the molecular mechanisms by which cancer cells can suppress multipolar mitoses is beginning to emerge. Here, we review what's currently known about centrosome clustering mechanisms and discuss potential strategies to target these mechanisms for the selective killing of cancer cells.
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Boveri revisited: chromosomal instability, aneuploidy and tumorigenesis. Nat Rev Mol Cell Biol 2009; 10:478-87. [PMID: 19546858 DOI: 10.1038/nrm2718] [Citation(s) in RCA: 643] [Impact Index Per Article: 42.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The mitotic checkpoint is a major cell cycle control mechanism that guards against chromosome missegregation and the subsequent production of aneuploid daughter cells. Most cancer cells are aneuploid and frequently missegregate chromosomes during mitosis. Indeed, aneuploidy is a common characteristic of tumours, and, for over 100 years, it has been proposed to drive tumour progression. However, recent evidence has revealed that although aneuploidy can increase the potential for cellular transformation, it also acts to antagonize tumorigenesis in certain genetic contexts. A clearer understanding of the tumour suppressive function of aneuploidy might reveal new avenues for anticancer therapy.
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Chandhok NS, Pellman D. A little CIN may cost a lot: revisiting aneuploidy and cancer. Curr Opin Genet Dev 2009; 19:74-81. [PMID: 19195877 DOI: 10.1016/j.gde.2008.12.004] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2008] [Revised: 12/06/2008] [Accepted: 12/09/2008] [Indexed: 01/05/2023]
Abstract
Despite over 100 years of study, the role of aneuploidy in cancer remains poorly understood. This review highlights the advances in understanding the causes and consequences of aneuploidy. Recent work has illuminated ways in which aneuploidy could have either tumor-promoting or tumor-suppressing effects, similar to what is known for other forms of genetic instability such as telomere attrition [Maser RS, DePinho RA: Connecting chromosomes, crisis, and cancer. Science 2002, 297:565-569]. We explore the possibility that aneuploidy could be just another type of 'mutation', with potential beneficial and deleterious effects, depending on the chromosomes involved and the specific selective pressures the cells experience. We also discuss the potential therapeutic implications of changes in physiology associated with aneuploidy.
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Affiliation(s)
- Namrata S Chandhok
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA.
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