Database : MEDLINE
Search on : chromosomal and instability [Words]
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[PMID]: 29520890
[Au] Autor:Deevi RK; Javadi A; McClements J; Vohhodina J; Savage K; Loughrey MB; Evergren E; Campbell FC
[Ad] Address:Centre for Cancer Research and Cell Biology, Queen's University of Belfast, Belfast, UK.
[Ti] Title:Protein kinase C zeta suppresses low- or high-grade colorectal cancer (CRC) phenotypes by interphase centrosome anchoring.
[So] Source:J Pathol;, 2018 Mar 09.
[Is] ISSN:1096-9896
[Cp] Country of publication:England
[La] Language:eng
[Ab] Abstract:Histological grading provides prognostic stratification of colorectal cancer (CRC) by scoring heterogeneous phenotypes. Features of aggressiveness include aberrant mitotic spindle configurations, chromosomal breakage, and bizarre multicellular morphology, but pathobiology is poorly understood. Protein kinase C zeta (PKCz) controls mitotic spindle dynamics, chromosome segregation, and multicellular patterns, but its role in CRC phenotype evolution remains unclear. Here, we show that PKCz couples genome segregation to multicellular morphology through control of interphase centrosome anchoring. PKCz regulates interdependent processes that control centrosome positioning. Among these, interaction between the cytoskeletal linker protein ezrin and its binding partner NHERF1 promotes the formation of a localized cue for anchoring interphase centrosomes to the cell cortex. Perturbation of these phenomena induced different outcomes in cells with single or extra centrosomes. Defective anchoring of a single centrosome promoted bipolar spindle misorientation, multi-lumen formation, and aberrant epithelial stratification. Collectively, these disturbances induce cribriform multicellular morphology that is typical of some categories of low-grade CRC. By contrast, defective anchoring of extra centrosomes promoted multipolar spindle formation, chromosomal instability (CIN), disruption of glandular morphology, and cell outgrowth across the extracellular matrix interface characteristic of aggressive, high-grade CRC. Because PKCz enhances apical NHERF1 intensity in 3D epithelial cultures, we used an immunohistochemical (IHC) assay of apical NHERF1 intensity as an indirect readout of PKCz activity in translational studies. We show that apical NHERF1 IHC intensity is inversely associated with multipolar spindle frequency and high-grade morphology in formalin-fixed human CRC samples. To conclude, defective PKCz control of interphase centrosome anchoring may underlie distinct categories of mitotic slippage that shape the development of low- or high-grade CRC phenotypes. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1803
[Cu] Class update date: 180309
[Lr] Last revision date:180309
[St] Status:Publisher
[do] DOI:10.1002/path.5035

  2 / 9805 MEDLINE  
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[PMID]: 29466339
[Au] Autor:Macheret M; Halazonetis TD
[Ad] Address:Department of Molecular Biology, University of Geneva, 1205 Geneva, Switzerland.
[Ti] Title:Intragenic origins due to short G1 phases underlie oncogene-induced DNA replication stress.
[So] Source:Nature;555(7694):112-116, 2018 Mar 01.
[Is] ISSN:1476-4687
[Cp] Country of publication:England
[La] Language:eng
[Ab] Abstract:Oncogene-induced DNA replication stress contributes critically to the genomic instability that is present in cancer. However, elucidating how oncogenes deregulate DNA replication has been impeded by difficulty in mapping replication initiation sites on the human genome. Here, using a sensitive assay to monitor nascent DNA synthesis in early S phase, we identified thousands of replication initiation sites in cells before and after induction of the oncogenes CCNE1 and MYC. Remarkably, both oncogenes induced firing of a novel set of DNA replication origins that mapped within highly transcribed genes. These ectopic origins were normally suppressed by transcription during G1, but precocious entry into S phase, before all genic regions had been transcribed, allowed firing of origins within genes in cells with activated oncogenes. Forks from oncogene-induced origins were prone to collapse, as a result of conflicts between replication and transcription, and were associated with DNA double-stranded break formation and chromosomal rearrangement breakpoints both in our experimental system and in a large cohort of human cancers. Thus, firing of intragenic origins caused by premature S phase entry represents a mechanism of oncogene-induced DNA replication stress that is relevant for genomic instability in human cancer.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1802
[Cu] Class update date: 180309
[Lr] Last revision date:180309
[St] Status:In-Data-Review
[do] DOI:10.1038/nature25507

  3 / 9805 MEDLINE  
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[PMID]: 29441364
[Au] Autor:Pal S; Postnikoff SD; Chavez M; Tyler JK
[Ad] Address:Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, NY 10065, USA.
[Ti] Title:Impaired cohesion and homologous recombination during replicative aging in budding yeast.
[So] Source:Sci Adv;4(2):eaaq0236, 2018 Feb.
[Is] ISSN:2375-2548
[Cp] Country of publication:United States
[La] Language:eng
[Ab] Abstract:The causal relationship between genomic instability and replicative aging is unclear. We reveal here that genomic instability at the budding yeast ribosomal DNA (rDNA) locus increases during aging, potentially due to the reduced cohesion that we uncovered during aging caused by the reduced abundance of multiple cohesin subunits, promoting increased global chromosomal instability. In agreement, cohesion is lost during aging at other chromosomal locations in addition to the rDNA, including centromeres. The genomic instability in old cells is exacerbated by a defect in DNA double-strand break (DSB) repair that we uncovered in old yeast. This was due to limiting levels of key homologous recombination proteins because overexpression of Rad51 or Mre11 reduced the accumulation of DSBs and largely restored DSB repair in old cells. We propose that increased rDNA instability and the reduced DSB repair capacity of old cells contribute to the progressive accumulation of global chromosomal DNA breaks, where exceeding a threshold of genomic DNA damage ends the replicative life span.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1802
[Cu] Class update date: 180309
[Lr] Last revision date:180309
[St] Status:In-Data-Review
[do] DOI:10.1126/sciadv.aaq0236

  4 / 9805 MEDLINE  
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[PMID]: 29516675
[Au] Autor:Silveira Zavalhia L; Weber Medeiros A; Oliveira Silva A; Vial Roehe A
[Ad] Address:Research Laboratory in Pathology, Graduate Program in Pathology of the Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Porto Alegre, Brazil.
[Ti] Title:Do FHIT gene alterations play a role in human solid tumors?
[So] Source:Asia Pac J Clin Oncol;, 2018 Mar 08.
[Is] ISSN:1743-7563
[Cp] Country of publication:Australia
[La] Language:eng
[Ab] Abstract:The fragile histidine triad (FHIT) gene encloses an active common chromosomal fragile site, FRA3B. This gene is known to be associated with genomic instability, apoptosis and DNA damage. FHIT disturbances have been related to carcinogenesis in different types of human tumor. Despite this, there are some controversies about the exact role of the FHIT gene in relation to tumor biology. Several pieces of evidence support the hypothesis that FHIT acts as a tumor suppressor gene. A loss or decrease in the Fhit protein expression appears to be related to tumor progression, poor prognostic factors and lower survival rates. The most frequent causes of FHIT expression changes are gene mutations, epigenetic alteration and loss of heterozygosity. This literature review aims to clarify the involvement of the FHIT gene in carcinogenesis, tumor progression and clinical outcome in prevalent solid malignancies, such as breast, lung, cervical, esophageal, gastric and colorectal cancers.
[Pt] Publication type:JOURNAL ARTICLE; REVIEW
[Em] Entry month:1803
[Cu] Class update date: 180308
[Lr] Last revision date:180308
[St] Status:Publisher
[do] DOI:10.1111/ajco.12868

  5 / 9805 MEDLINE  
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[PMID]: 29425284
[Au] Autor:Katari S; Aarabi M; Kintigh A; Mann S; Yatsenko SA; Sanfilippo JS; Zeleznik AJ; Rajkovic A
[Ad] Address:Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine, University of Pittsburgh, 300 Halket Street, Pittsburgh, PA 15213, USA.
[Ti] Title:Chromosomal instability in women with primary ovarian insufficiency.
[So] Source:Hum Reprod;, 2018 Feb 07.
[Is] ISSN:1460-2350
[Cp] Country of publication:England
[La] Language:eng
[Ab] Abstract:STUDY QUESTION: What is the prevalence of somatic chromosomal instability among women with idiopathic primary ovarian insufficiency (POI)? SUMMARY ANSWER: A subset of women with idiopathic POI may have functional impairment in DNA repair leading to chromosomal instability in their soma. WHAT IS KNOWN ALREADY: The formation and repair of DNA double-strand breaks during meiotic recombination are fundamental processes of gametogenesis. Oocytes with compromised DNA integrity are susceptible to apoptosis which could trigger premature ovarian aging and accelerated wastage of the human follicle reserve. Genomewide association studies, as well as whole exome sequencing, have implicated multiple genes involved in DNA damage repair. However, the prevalence of defective DNA damage repair in the soma of women with POI is unknown. STUDY DESIGN, SIZE, DURATION: In total, 46 women with POI and 15 family members were evaluated for excessive mitomycin-C (MMC)-induced chromosome breakage. Healthy fertile females (n = 20) and two lymphoblastoid cell lines served as negative and as positive controls, respectively. PARTICIPANTS/MATERIALS, SETTING, METHODS: We performed a pilot functional study utilizing MMC to assess chromosomal instability in the peripheral blood of participants. A high-resolution array comparative genomic hybridization (aCGH) was performed on 16 POI patients to identify copy number variations (CNVs) for a set of 341 targeted genes implicated in DNA repair. MAIN RESULTS AND THE ROLE OF CHANCE: Array CGH revealed three POI patients (3/16, 18.8%) with pathogenic CNVs. Excessive chromosomal breakage suggestive of a constitutional deficiency in DNA repair was detected in one POI patient with the 16p12.3 duplication. In two patients with negative chromosome breakage analysis, aCGH detected a Xq28 deletion comprising the Centrin EF-hand Protein 2 (CETN2) and HAUS Augmin Like Complex Subunit 7 (HAUS7) genes essential for meiotic DNA repair, and a duplication in the 3p22.2 region comprising a part of the ATPase domain of the MutL Homolog 1 (MLH1) gene. LIMITATIONS REASONS FOR CAUTION: Peripheral lymphocytes, used as a surrogate tissue to quantify induced chromosome damage, may not be representative of all the affected tissues. Another limitation pertains to the MMC assay which detects homologous repair pathway defects and does not test deficiencies in other DNA repair pathways. WIDER IMPLICATIONS OF THE FINDINGS: Our results provide evidence for functional impairment of DNA repair in idiopathic POI, which may predispose the patients to other DNA repair-related conditions such as accelerated aging and/or cancer susceptibility. STUDY FUNDING/COMPETING INTEREST(S): Funding was provided by the National Institute of Child Health and Human Development. There were no competing interests to declare.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1802
[Cu] Class update date: 180308
[Lr] Last revision date:180308
[St] Status:Publisher
[do] DOI:10.1093/humrep/dey012

  6 / 9805 MEDLINE  
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[PMID]: 29420752
[Au] Autor:Berkovitz A; Dekel Y; Goldstein R; Bsoul S; Machluf Y; Bercovich D
[Ad] Address:Sackler Faculty of Medicine, Tel Aviv University, PO Box 39040, Tel Aviv 6997801, Israel.
[Ti] Title:The significance of human spermatozoa vacuoles can be elucidated by a novel procedure of array comparative genomic hybridization.
[So] Source:Hum Reprod;, 2018 Feb 06.
[Is] ISSN:1460-2350
[Cp] Country of publication:England
[La] Language:eng
[Ab] Abstract:STUDY QUESTION: Is there an association between spermatozoon genomic stability and vacuolar morphology and location? SUMMARY ANSWER: The genomic stability of spermatozoa is associated with specific characteristics of vacuolar morphology (depth) and location (cellular compartment, i.e. nucleus and equatorial region). WHAT IS KNOWN ALREADY: Genetic anomalies in sperm are correlated with semen abnormalities, yet the advantage of morphologically based selection of spermatozoa for IVF according to current criteria is controversial. Selection criteria based on the number of vacuoles and their size have been proposed and are widely applied. Nevertheless, it has not improved the ICSI success rates, suggesting the currently used vacuole criteria are incomplete. STUDY DESIGN, SIZE, DURATION: Normal sperm according to Motile Sperm Organelle Morphology Examination criteria (MSOME) and common vacuole grading were evaluated. An additional evaluation of sperm vacuole morphology according to novel vacuole criteria (i.e. location and depth) was conducted. An assessment to align these specific vacuolar morphology features with genomic stability was conducted among spermatozoa from infertile patients and healthy fertile donors aged 24-38 between June 2015 and July 2016. PARTICIPANTS/MATERIALS, SETTING, METHODS: Single spermatozoa (n = 53) from 16 infertile patients and 14 fertile donors were morphologically and genetically evaluated. Each spermatozoon was examined morphologically, by ultra-magnification ×6300, and genetically by a novel comparative genomic hybridization protocol, without the use of reference DNA, to assess chromosomal instability as evident by copy number variations (CNV). MAIN RESULTS AND THE ROLE OF CHANCE: We established an association between genomic stability and vacuolar morphology as a base for a new classification according to novel vacuolar criteria, specifically depth and location. Genomic instability was found to be related to these two main features of vacuoles and, surprisingly not to the number and size of vacuoles as in the previously proposed classifications. High CNV spermatozoa were characterized by vacuoles located in the nucleus and/or equatorial segment or by deep vacuoles, while, low CNV spermatozoa were characterized by a complete lack of vacuoles or non-deep vacuoles not located in the nucleus/equatorial segment. A putative threshold of ~265 CNV was deduced to distinguish between genetically stable and unstable spermatozoa, and 94% of the tested spermatozoa segregated accordingly. LIMITATIONS REASONS FOR CAUTION: A relatively small sample of spermatozoa were examined-53 in total. However, the association between vacuoles location and morphology and genomic stability was significant. This is the first study evaluating spermatozoon genomic stability with respect to vacuole morphology according to novel vacuole criteria (i.e. location and depth) and further investigation is warranted to verify the value of these criteria in larger sample size clinical studies. WIDER IMPLICATIONS OF THE FINDINGS: Our results, which are based on spermatozoon vacuoles morphological classification and genomic parameters, indicate an association between vacuoles morphology and location and genomic stability. The data presented herein suggest the existence of subpopulations of spermatozoa potentially appropriate for IVF-ICSI, as they appear normal according to the current MSOME and vacuoles classification, however they are almost certainly genetically damaged. As current criteria have yet to achieve an unequivocal evaluation of the implantation potential of a given spermatozoon, we propose novel criteria, based on specific vacuolar morphological traits; depth and location, as these were found aligned with genomic findings. STUDY FUNDING/COMPETING INTEREST(S): No funding was received for this study. The authors have no conflict of interest to declare. TRIAL REGISTRATION NUMBER: N/A.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1802
[Cu] Class update date: 180308
[Lr] Last revision date:180308
[St] Status:Publisher
[do] DOI:10.1093/humrep/dey019

  7 / 9805 MEDLINE  
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[PMID]: 29244163
[Au] Autor:Greaney J; Wei Z; Homer H
[Ad] Address:Christopher Chen Oocyte Biology Research Laboratory, Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Royal Brisbane & Women's Hospital Campus, Herston QLD 4029, Australia.
[Ti] Title:Regulation of chromosome segregation in oocytes and the cellular basis for female meiotic errors.
[So] Source:Hum Reprod Update;, 2017 Dec 13.
[Is] ISSN:1460-2369
[Cp] Country of publication:England
[La] Language:eng
[Ab] Abstract:BACKGROUND: Meiotic chromosome segregation in human oocytes is notoriously error-prone, especially with ageing. Such errors markedly reduce the reproductive chances of increasing numbers of women embarking on pregnancy later in life. However, understanding the basis for these errors is hampered by limited access to human oocytes. OBJECTIVE AND RATIONALE: Important new discoveries have arisen from molecular analyses of human female recombination and aneuploidy along with high-resolution analyses of human oocyte maturation and mouse models. Here, we review these findings to provide a contemporary picture of the key players choreographing chromosome segregation in mammalian oocytes and the cellular basis for errors. SEARCH METHODS: A search of PubMed was conducted using keywords including meiosis, oocytes, recombination, cohesion, cohesin complex, chromosome segregation, kinetochores, spindle, aneuploidy, meiotic cell cycle, spindle assembly checkpoint, anaphase-promoting complex, DNA damage, telomeres, mitochondria, female ageing and female fertility. We extracted papers focusing on mouse and human oocytes that best aligned with the themes of this review and that reported transformative and novel discoveries. OUTCOMES: Meiosis incorporates two sequential rounds of chromosome segregation executed by a spindle whose component microtubules bind chromosomes via kinetochores. Cohesion mediated by the cohesin complex holds chromosomes together and should be resolved at the appropriate time, in a specific step-wise manner and in conjunction with meiotically programmed kinetochore behaviour. In women, the stage is set for meiotic error even before birth when female-specific crossover maturation inefficiency leads to the formation of at-risk recombination patterns. In adult life, multiple co-conspiring factors interact with at-risk crossovers to increase the likelihood of mis-segregation. Available evidence support that these factors include, but are not limited to, cohesion deterioration, uncoordinated sister kinetochore behaviour, erroneous microtubule attachments, spindle instability and structural chromosomal defects that impact centromeres and telomeres. Data from mice indicate that cohesin and centromere-specific histones are long-lived proteins in oocytes. Since these proteins are pivotal for chromosome segregation, but lack any obvious renewal pathway, their deterioration with age provides an appealing explanation for at least some of the problems in older oocytes. WIDER IMPLICATIONS: Research in the mouse model has identified a number of candidate genes and pathways that are important for chromosome segregation in this species. However, many of these have not yet been investigated in human oocytes so it is uncertain at this stage to what extent they apply to women. The challenge for the future involves applying emerging knowledge of female meiotic molecular regulation towards improving clinical fertility management.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1712
[Cu] Class update date: 180308
[Lr] Last revision date:180308
[St] Status:Publisher
[do] DOI:10.1093/humupd/dmx035

  8 / 9805 MEDLINE  
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[PMID]: 29466793
[Au] Autor:Xu JF; Kang Q; Ma XY; Pan YM; Yang L; Jin P; Wang X; Li CG; Chen XC; Wu C; Jiao SZ; Sheng JQ
[Ad] Address:Chinese PLA General Hospital, Chinese PLA Medical School, Beijing, China.
[Ti] Title:A Novel Method to Detect Early Colorectal Cancer Based on Chromosome Copy Number Variation in Plasma.
[So] Source:Cell Physiol Biochem;45(4):1444-1454, 2018.
[Is] ISSN:1421-9778
[Cp] Country of publication:Switzerland
[La] Language:eng
[Ab] Abstract:BACKGROUND/AIMS: Colonoscopy screening has been accepted broadly to evaluate the risk and incidence of colorectal cancer (CRC) during health examination in outpatients. However, the intrusiveness, complexity and discomfort of colonoscopy may limit its application and the compliance of patients. Thus, more reliable and convenient diagnostic methods are necessary for CRC screening. Genome instability, especially copy-number variation (CNV), is a hallmark of cancer and has been proved to have potential in clinical application. METHODS: We determined the diagnostic potential of chromosomal CNV at the arm level by whole-genome sequencing of CRC plasma samples (n = 32) and healthy controls (n = 38). Arm level CNV was determined and the consistence of arm-level CNV between plasma and tissue was further analyzed. Two methods including regular z score and trained Support Vector Machine (SVM) classifier were applied for detection of colorectal cancer. RESULTS: In plasma samples of CRC patients, the most frequent deletions were detected on chromosomes 6, 8p, 14q and 1p, and the most frequent amplifications occurred on chromosome 19, 5, 2, 9p and 20p. These arm-level alterations detected in plasma were also observed in tumor tissues. We showed that the specificity of regular z score analysis for the detection of colorectal cancer was 86.8% (33/38), whereas its sensitivity was only 56.3% (18/32). Applying a trained SVM classifier (n = 40 in trained group) as the standard to detect colorectal cancer relevance ratio in the test samples (n = 30), a sensitivity of 91.7% (11/12) and a specificity 88.9% (16/18) were finally reached. Furthermore, all five early CRC patients in stages I and II were successfully detected. CONCLUSION: Trained SVM classifier based on arm-level CNVs can be used as a promising method to screen early-stage CRC.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1802
[Cu] Class update date: 180306
[Lr] Last revision date:180306
[St] Status:In-Process
[do] DOI:10.1159/000487571

  9 / 9805 MEDLINE  
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[PMID]: 29445165
[Au] Autor:Tiwari A; Addis Jones O; Chan KL
[Ad] Address:Chromosome Dynamics and Stability Group, Genome Damage and Stability Centre, University of Sussex, Brighton, BN1 9RQ, UK.
[Ti] Title:53BP1 can limit sister-chromatid rupture and rearrangements driven by a distinct ultrafine DNA bridging-breakage process.
[So] Source:Nat Commun;9(1):677, 2018 02 14.
[Is] ISSN:2041-1723
[Cp] Country of publication:England
[La] Language:eng
[Ab] Abstract:Chromosome missegregation acts as one of the driving forces for chromosome instability and cancer development. Here, we find that in human cancer cells, HeLa and U2OS, depletion of 53BP1 (p53-binding protein 1) exacerbates chromosome non-disjunction resulting from a new type of sister-chromatid intertwinement, which is distinct from FANCD2-associated ultrafine DNA bridges (UFBs) induced by replication stress. Importantly, the sister DNA intertwinements trigger gross chromosomal rearrangements through a distinct process, named sister-chromatid rupture and bridging. In contrast to conventional anaphase bridge-breakage models, we demonstrate that chromatid axes of the intertwined sister-chromatids rupture prior to the breakage of the DNA bridges. Consequently, the ruptured sister arms remain tethered and cause signature chromosome rearrangements, including whole-arm (Robertsonian-like) translocation/deletion and isochromosome formation. Therefore, our study reveals a hitherto unreported chromatid damage phenomenon mediated by sister DNA intertwinements that may help to explain the development of complex karyotypes in tumour cells.
[Pt] Publication type:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Entry month:1802
[Cu] Class update date: 180307
[Lr] Last revision date:180307
[St] Status:In-Process
[do] DOI:10.1038/s41467-018-03098-y

  10 / 9805 MEDLINE  
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[PMID]: 29393405
[Au] Autor:Ohmine S; Salisbury JL; Ingle J; Pettinato G; Haddox CL; Haddad T; Galanis E; Ikeda Y; D'assoro AB
[Ad] Address:Department of Molecular Medicine, Mayo Clinic College of Medicine and Science, Rochester, MN 55905, USA.
[Ti] Title:Aurora-A overexpression is linked to development of aggressive teratomas derived from human iPS cells.
[So] Source:Oncol Rep;39(4):1725-1730, 2018 Apr.
[Is] ISSN:1791-2431
[Cp] Country of publication:Greece
[La] Language:eng
[Ab] Abstract:The discovery of human induced pluripotent stem cells (hiPSCs) is a promising advancement in the field of regenerative and personalized medicine. Expression of SOX2, KLF4, OCT4 and MYC transcription factors induces the nuclear reprogramming of somatic cells into hiPSCs that share striking similarities with human embryonic stem cells (hESCs). However, several studies have demonstrated that hESCs and hiPSCs could lead to teratoma formation in vivo, thus limiting their current clinical applications. Aberrant cell cycle regulation of hESCs is linked to centrosome amplification, which may account, for their enhanced chromosomal instability (CIN), and thus increase their tumorigenicity. Significantly, the tumor suppressor p53 plays a key role as a 'guardian of reprogramming', safeguarding genomic integrity during hiPSC reprogramming. Nevertheless, the molecular mechanisms leading to development of CIN during reprogramming and increased tumorigenic potential of hiPSCs remains to be fully elucidated. In the present study, we analyzed CIN in hiPSCs derived from keratinocytes and established that chromosomal and mitotic aberrations were linked to centrosome amplification, Aurora-A overexpression, abrogation of p53-mediated G1/S cell cycle checkpoint and loss of Rb tumor-suppressor function. When hiPSCs were transplanted into the kidney capsules of immunocompromised mice, they developed high-grade teratomas characterized by the presence of cells that exhibited non-uniform shapes and sizes, high nuclear pleomorphism and centrosome amplification. Significantly, ex vivo cells derived from teratomas exhibited high self-renewal capacity that was linked to Aurora-A kinase activity and gave rise to lung metastasis when injected into the tail vein of immunocompromised mice. Collectively, these findings demonstrated a high risk for malignancy of hiPSCs that exhibit Aurora-A overexpression, loss of Rb function, centrosome amplification and CIN. Based on these findings, we proposed that Aurora-A-targeted therapy could represent a promising prophylactic therapeutic strategy to decrease the likelihood of CIN and development of aggressive teratomas derived from hiPSCs.
[Pt] Publication type:JOURNAL ARTICLE
[Em] Entry month:1802
[Cu] Class update date: 180307
[Lr] Last revision date:180307
[St] Status:In-Process
[do] DOI:10.3892/or.2018.6239


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