101
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Kovalska VB, Volkova KD, Losytskyy MY, Tolmachev OI, Balanda AO, Yarmoluk SM. 6,6'-Disubstituted benzothiazole trimethine cyanines--new fluorescent dyes for DNA detection. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2006; 65:271-7. [PMID: 16497542 DOI: 10.1016/j.saa.2005.10.042] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2005] [Revised: 10/13/2005] [Accepted: 10/20/2005] [Indexed: 05/06/2023]
Abstract
The influence of methyl-, 2-hydroxyethyl-, dimethyl-, diethyl- and benzoyl-amino substituents in the 6,6'-positions of benzothiazole heterocycle of trimethine cyanines on their spectral-luminescent properties and behavior in presence of DNA, RNA and BSA was studied. It was shown that incorporation of 6,6'-substituents generally leads to the increase in dyes tendency to aggregation, resulting in the considerable decrease in the emission intensity of the disubstituted dyes as compared to the unsubstituted ones. Emission of the studied 6,6'-disubstited dyes in DNA presence is considerably more intensive than in presence of RNA, that points on the existing of DNA binding preference for the mentioned dyes. Insertion of benzoyl-amino groups into the 6,6'-positions permitted us to design the DNA-sensitive dyes on the basis of symmetric trimethine cyanines with unsubstituted polymethine chain, while typically such dyes slightly respond on the presence of biopolymers. 6,6'-Benzoyl-amino-disubstituted trimethine cyanines are proposed as efficient dyes for DNA detection.
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Affiliation(s)
- Vladyslava B Kovalska
- Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine, 150 Zabolotnogo St., 03143 Kyiv, Ukraine
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102
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Glaviano A, Nayak V, Cabuy E, Baird DM, Yin Z, Newson R, Ladon D, Rubio MA, Slijepcevic P, Lyng F, Mothersill C, Case CP. Effects of hTERT on metal ion-induced genomic instability. Oncogene 2006; 25:3424-35. [PMID: 16449970 DOI: 10.1038/sj.onc.1209399] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
There is currently a great interest in delayed chromosomal and other damaging effects of low-dose exposure to a variety of pollutants which appear collectively to act through induction of stress-response pathways related to oxidative stress and ageing. These have been studied mostly in the radiation field but evidence is accumulating that the mechanisms can also be triggered by chemicals, especially heavy metals. Humans are exposed to metals, including chromium (Cr) (VI) and vanadium (V) (V), from the environment, industry and surgical implants. Thus, the impact of low-dose stress responses may be larger than expected from individual toxicity projections. In this study, a short (24 h) exposure of human fibroblasts to low doses of Cr (VI) and V (V) caused both acute chromosome damage and genomic instability in the progeny of exposed cells for at least 30 days after exposure. Acutely, Cr (VI) caused chromatid breaks without aneuploidy while V (V) caused aneuploidy without chromatid breaks. The longer-term genomic instability was similar but depended on hTERT positivity. In telomerase-negative hTERT- cells, Cr (VI) and V (V) caused a long lasting and transmissible induction of dicentric chromosomes, nucleoplasmic bridges, micronuclei and aneuploidy. There was also a long term and transmissible reduction of clonogenic survival, with an increased beta-galactosidase staining and apoptosis. This instability was not present in telomerase-positive hTERT+ cells. In contrast, in hTERT+ cells the metals caused a persistent induction of tetraploidy, which was not noted in hTERT- cells. The growth and survival of both metal-exposed hTERT+ and hTERT- cells differed if they were cultured at subconfluent levels or plated out as colonies. Genomic instability is considered to be a driving force towards cancer. This study suggests that the type of genomic instability in human cells may depend critically on whether they are telomerase-positive or -negative and that their sensitivities to metals could depend on whether they are clustered or diffuse.
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Affiliation(s)
- A Glaviano
- Bristol Implant Research Centre, University of Bristol, Bristol, UK
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103
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Sikkema-Raddatz B, Suijkerbuijk R, Bouman K, de Jong B, Buys CHCM, te Meerman GJ. Quality aspects of prenatal cytogenetic diagnosis: determining the effect of various factors involved in handling amniotic fluid and chorionic villus material for cytogenetic diagnosis. Prenat Diagn 2006; 26:791-800. [PMID: 16821245 DOI: 10.1002/pd.1505] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
OBJECTIVES To investigate the effect of factors involved in cell culturing and slide preparation of amniotic fluid (AF) and chorionic villus biopsies (CVB) for prenatal cytogenetic diagnosis. METHODS The effect on the outcome of our standard AF cell culture procedure of volume and appearance of the submitted AF specimen, gynaecologist performing the amniocentesis, week of gestation in which the specimen was taken and culture medium was retrospectively investigated. In a prospective study controlled experimental variation was introduced in composition of fixative, relative humidity, temperature and airflow during slide preparation from primary CVB and AF in situ cultures. For evaluation, analysis of regression or variance was used. RESULTS Provided that at least 0.8 mL AF per culture dish was admitted, none of the investigated factors appeared as critical resulting in unacceptable variation in outcome. Variation in appearance of the AF had a relatively major impact: bloody or brown AF resulted in a 3 days longer culture time. To a limited degree, metaphase quality of AF and CVB cells was affected by composition of fixative, relative humidity, ambient temperature and airflow during slide preparation. CONCLUSION Current prenatal cytogenetic practice as described here appears in general to be robust and reliable. The investigated conditions are not critical within the investigated range. Expensive measures for fine control of these conditions are, therefore, not required.
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Affiliation(s)
- Birgit Sikkema-Raddatz
- Department of Medical Genetics, University Medical Center Groningen, Postbus 300001, 9700 RB Groningen, The Netherlands.
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104
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Mansouri MR, Marklund L, Gustavsson P, Davey E, Carlsson B, Larsson C, White I, Gustavson KH, Dahl N. Loss of ZDHHC15 expression in a woman with a balanced translocation t(X;15)(q13.3;cen) and severe mental retardation. Eur J Hum Genet 2005; 13:970-7. [PMID: 15915161 DOI: 10.1038/sj.ejhg.5201445] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
X-linked mental retardation (XLMR) affects one in 600 males and is highly heterogeneous. We describe here a 29-year-old woman with severe nonsyndromic mental retardation and a balanced reciprocal translocation between chromosomes X and 15 [46,XX,t(X;15)(q13.3;cen)]. Methylation studies showed a 100% skewed X-inactivation in patient-derived lymphocytes indicating that the normal chromosome X is retained inactive. Physical mapping of the breakpoints localised the Xq13.3 breakpoint to within 3.9 kb of the first exon of the ZDHHC15 gene encoding a zinc-finger and a DHHC domain containing product. Expression analysis revealed that different transcript variants of the gene are expressed in brain. ZDHHC15-specific RT-PCR analysis on lymphocytes from the patient revealed an absence of ZDHHC15 transcript variants, detected in control samples. We suggest that the absence of the ZDHHC15 transcripts in this patient contributes to her phenotype, and that the gene is a strong candidate for nonsyndromic XLMR.
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105
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Stefan M, Claiborn KC, Stasiek E, Chai JH, Ohta T, Longnecker R, Greally JM, Nicholls RD. Genetic mapping of putative Chrna7 and Luzp2 neuronal transcriptional enhancers due to impact of a transgene-insertion and 6.8 Mb deletion in a mouse model of Prader-Willi and Angelman syndromes. BMC Genomics 2005; 6:157. [PMID: 16280085 PMCID: PMC1322230 DOI: 10.1186/1471-2164-6-157] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2005] [Accepted: 11/09/2005] [Indexed: 02/03/2023] Open
Abstract
Background Prader-Willi and Angelman syndrome (PWS and AS) patients typically have an ~5 Mb deletion of human chromosome 15q11-q13, of opposite parental origin. A mouse model of PWS and AS has a transgenic insertion-deletion (TgPWS/TgAS) of chromosome 7B/C subsequent to paternal or maternal inheritance, respectively. In this study, we define the deletion endpoints and examine the impact on expression of flanking genes. Results Using molecular and cytological methods we demonstrate that 13 imprinted and 11 non-imprinted genes are included in the TgPWS/TgAS deletion. Normal expression levels were found in TgPWS brain for genes extending 9.1- or 5.6-Mb centromeric or telomeric of the deletion, respectively. Our molecular cytological studies map the proximal deletion breakpoint between the Luzp2 and Siglec-H loci, and we show that overall mRNA levels of Luzp2 in TgPWS and TgAS brain are significantly reduced by 17%. Intriguingly, 5' Chrna7 shows 1.7-fold decreased levels in TgPWS and TgAS brain whereas there is a ≥15-fold increase in expression in neonatal liver and spleen of these mouse models. By isolating a Chrna7-Tg fusion transcript from TgAS mice, we mapped the telomeric deletion breakpoint in Chrna7 intron 4. Conclusion Based on the extent of the deletion, TgPWS/TgAS mice are models for PWS/AS class I deletions. Other than for the first gene promoters immediately outside the deletion, since genes extending 5.6–9.1 Mb away from each end of the deletion show normal expression levels in TgPWS brain, this indicates that the transgene array does not induce silencing and there are no additional linked rearrangements. Using gene expression, non-coding conserved sequence (NCCS) and synteny data, we have genetically mapped a putative Luzp2 neuronal enhancer responsible for ~33% of allelic transcriptional activity. The Chrna7 results are explained by hypothesizing loss of an essential neuronal transcriptional enhancer required for ~80% of allelic Chrna7 promoter activity, while the Chrna7 promoter is upregulated in B lymphocytes by the transgene immunoglobulin enhancer. The mapping of a putative Chrna7 neuronal enhancer inside the deletion has significant implications for understanding the transcriptional regulation of this schizophrenia-susceptibility candidate gene.
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Affiliation(s)
- Mihaela Stefan
- Center for Neurobiology and Behavior, Department of Psychiatry, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Pediatrics, Children's Hospital of Pittsburgh, 3460 Fifth Avenue, Pittsburgh, PA 15213
| | - Kathryn C Claiborn
- Center for Neurobiology and Behavior, Department of Psychiatry, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Edyta Stasiek
- Division of Hematology, Department of Medicine, Albert Einstein College of Medicine, The Bronx, USA
| | - Jing-Hua Chai
- Center for Neurobiology and Behavior, Department of Psychiatry, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Tohru Ohta
- Center for Neurobiology and Behavior, Department of Psychiatry, University of Pennsylvania, Philadelphia, PA 19104, USA
- Health Science University of Hokkaido, Hokkaido, Japan
| | - Richard Longnecker
- Department of Microbiology and Immunology, Feinberg School of Medicine, Northwestern University, Ward 6-231, 303 East Chicago Ave, Chicago, IL 60611, USA
| | - John M Greally
- Division of Hematology, Department of Medicine, Albert Einstein College of Medicine, The Bronx, USA
| | - Robert D Nicholls
- Center for Neurobiology and Behavior, Department of Psychiatry, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Genetics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Birth Defects Laboratories, Children's Hospital of Pittsburgh, Room 2109 Rangos Research Center, 3460 Fifth Avenue, Pittsburgh, PA 15213, USA
- Department of Pediatrics, Children's Hospital of Pittsburgh, 3460 Fifth Avenue, Pittsburgh, PA 15213
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106
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Winrow CJ, Pankratz DG, Vibat CRT, Bowen TJ, Callahan MA, Warren AJ, Hilbush BS, Wynshaw-Boris A, Hasel KW, Weaver Z, Lockhart DJ, Barlow C. Aberrant recombination involving the granzyme locus occurs in Atm-/- T-cell lymphomas. Hum Mol Genet 2005; 14:2671-84. [PMID: 16087685 DOI: 10.1093/hmg/ddi301] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Ataxia telangiectasia (A-T) is an autosomal recessive disease caused by loss of function of the serine/threonine protein kinase ATM (ataxia telangiectasia mutated). A-T patients have a 250-700-fold increased risk of developing lymphomas and leukemias which are typically highly invasive and proliferative. In addition, a subset of adult acute lymphoblastic leukemias and aggressive B-cell chronic lymphocytic leukemias that occur in the general population show loss of heterozygosity for ATM. To define the specific role of ATM in lymphomagenesis, we studied T-cell lymphomas isolated from mice with mutations in ATM and/or p53 using cytogenetic analysis and mRNA transcriptional profiling. The analyses identified genes misregulated as a consequence of the amplifications, deletions and translocation events arising as a result of ATM loss. A specific recurrent disruption of the granzyme gene family locus was identified resulting in an aberrant granzyme B/C fusion product. The combined application of cytogenetic and gene expression approaches identified specific loci and genes that define the pathway of initiation and progression of lymphoreticular malignancies in the absence of ATM.
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Affiliation(s)
- Christopher J Winrow
- The Salk Institute for Biological Studies, The Laboratory of Genetics, 10010 North Torrey Pines Road, La Jolla, CA 92037, USA
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107
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Bellani MA, Romanienko PJ, Cairatti DA, Camerini-Otero RD. SPO11 is required for sex-body formation, and Spo11 heterozygosity rescues the prophase arrest ofAtm-/- spermatocytes. J Cell Sci 2005; 118:3233-45. [PMID: 15998665 DOI: 10.1242/jcs.02466] [Citation(s) in RCA: 154] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
SPO11 introduces double-strand breaks (DSBs) that trigger the phosphorylation of H2AX during meiotic prophase. In mice, SPO11 is strictly required for initiation of meiotic recombination and synapsis, yet SPO11 is still considered to be dispensable for sex-body formation in mouse spermatocytes. We provide conclusive evidence showing that functional SPO11, and consequently recombination and synapsis, are required for phosphorylation of H2AX in the X-Y chromatin and for sex-body formation in mouse spermatocytes. We investigated the role in meiosis of the three kinases [ATM (ataxia telangiectasia mutated), ATR (ataxia-telangiectasia- and Rad-3-related) and DNA-PKcs (DNA-dependent-protein-kinase catalytic subunit)] known to phosphorylate H2AX in mitotic cells. We found that DNA-PKcs can be ruled out as an essential kinase in this process, whereas ATM is strictly required for the chromatin-wide phosphorylation of H2AX occurring in leptotene spermatocytes in response to DSBs. Remarkably, we discovered that Spo11 heterozygosity can rescue the prophase-I-arrest characteristic of ATM-deficient spermatocytes. Characterization of the rescued Atm-/-Spo11+/- mutant indicates that ATM is dispensable for sex-body formation and phosphorylation of H2AX in this subnuclear domain. The co-localization of ATR, phosphorylated H2AX and the sex chromatin observed in the Atm-/-Spo11+/- mutant, along with ATR transcription kinetics during the first wave of spermatogenesis, confirm and expand recent findings indicating that ATR is the kinase involved in H2AX phosphorylation in the sex body.
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Affiliation(s)
- Marina A Bellani
- Genetics and Biochemistry Branch, NIDDK, NIH, Bethesda, MD 20892, USA
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108
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Hou F, Zou H. Two human orthologues of Eco1/Ctf7 acetyltransferases are both required for proper sister-chromatid cohesion. Mol Biol Cell 2005; 16:3908-18. [PMID: 15958495 PMCID: PMC1182326 DOI: 10.1091/mbc.e04-12-1063] [Citation(s) in RCA: 157] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2004] [Revised: 05/23/2005] [Accepted: 06/03/2005] [Indexed: 11/11/2022] Open
Abstract
Genetic studies in yeast and Drosophila have uncovered a conserved acetyltransferase involved in sister-chromatid cohesion. Here, we described the two human orthologues, previously named EFO1/ESCO1 and EFO2/ESCO2. Similar to their yeast (Eco1/Ctf7 and Eso1) and fly (deco) counterparts, both proteins feature a conserved C-terminal domain consisting of a H2C2 zinc finger motif and an acetyltransferase domain that is able to catalyze autoacetylation reaction in vitro. However, no similarity can be detected outside of the conserved domain. RNA interference depletion experiment revealed that EFO1/ESCO1 and EFO2/ESCO2 were not redundant and that both were required for proper sister-chromatid cohesion. The difference between EFO1 and EFO2 also is reflected in their cell cycle regulation. In mitosis, EFO1 is phosphorylated, whereas EFO2 is degraded. Furthermore, both proteins associate with chromosomes, and the chromosome binding depends on the diverse N-terminal domains. We propose that EFO1 and EFO2 are targeted to different chromosome structures to help establish or maintain sister-chromatid cohesion.
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Affiliation(s)
- Fajian Hou
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9148, USA
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109
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Muslumanoglu HM, Oner U, Ozalp S, Acikalin MF, Yalcin OT, Ozdemir M, Artan S. Genetic imbalances in endometrial hyperplasia and endometrioid carcinoma detected by comparative genomic hybridization. Eur J Obstet Gynecol Reprod Biol 2005; 120:107-14. [PMID: 15866096 DOI: 10.1016/j.ejogrb.2004.08.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2004] [Revised: 05/28/2004] [Accepted: 08/05/2004] [Indexed: 10/26/2022]
Abstract
OBJECTIVE To evaluate the sequential genomic copy alterations related to the development of precursor lesions and endometrioid-type endometrial carcinomas, and its association with cellular atypia. STUDY DESIGN Paraffin-embedded tissue specimens from 32 cases of endometrial hyperplasia, 15 of endometrial carcinoma, and 20 of normal endometrial tissue were retrospectively evaluated by the comparative genomic hybridization (CGH) technique. The average number of copy alterations (ANCA) index was used to define the incidence of genomic imbalances in each tissue group. Identified sequential genetic abnormalities were compared with the final histopathological diagnosis and the cellular atypia. RESULTS Detectable and consistent chromosomal imbalances were found in 13 hyperplasia and 9 carcinoma specimens. There was a significant correlation between ANCA value and degree of cellular atypia and tumor grade. While 1p36-pter, 20q deletions, and 4q overrepresentation were the most prevalent imbalances detected in both complex hyperplasia and complex atypical hyperplasia, 17q22-qter deletion and amplification of 2p34 were only seen in hyperplasia with atypical cells. Overrepresentations of chromosomes 8q, 1q, and 3q are the most frequent aberrations in endometrial carcinomas, but were absent from all the precursor lesions except one. Underrepresentations of chromosomes 1p36-pter and 10q are the other commonly seen aberrations in carcinomas, the latter being more frequent in moderately differentiated than in poorly differentiated lesions. CONCLUSIONS Different patterns of chromosomal aberrations are seen in precursor lesions than in endometrial carcinomas, except for the loss of 1p36-pter. The presence of 1p deletion in both endometrial hyperplasia and cancer specimens suggests that this is an early event in the development of carcinoma. These results support a stepwise mode of tumorigenesis with accumulation of a series of genomic copy alterations in endometrial carcinogenesis.
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MESH Headings
- Chromosome Aberrations
- Chromosomes, Human, Pair 1/genetics
- Chromosomes, Human, Pair 17/genetics
- Chromosomes, Human, Pair 2/genetics
- Chromosomes, Human, Pair 20/genetics
- Chromosomes, Human, Pair 3/genetics
- Chromosomes, Human, Pair 4/genetics
- Chromosomes, Human, Pair 8/genetics
- Endometrial Hyperplasia/genetics
- Endometrial Hyperplasia/pathology
- Endometrial Neoplasms/genetics
- Endometrial Neoplasms/pathology
- Female
- Gene Deletion
- Humans
- Middle Aged
- Nucleic Acid Hybridization
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Affiliation(s)
- Hamza M Muslumanoglu
- Department of Medical Genetics, Osmangazi University Medical Faculty, 26480 Eskisehir, Turkey
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110
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Sjögren-Jansson E, Zetterström M, Moya K, Lindqvist J, Strehl R, Eriksson PS. Large-scale propagation of four undifferentiated human embryonic stem cell lines in a feeder-free culture system. Dev Dyn 2005; 233:1304-14. [PMID: 15965986 DOI: 10.1002/dvdy.20459] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
We describe an improved and more robust protocol for transfer and subsequent propagation of human embryonic stem cells under feeder-free conditions. The results show that mechanical dissociation for transfer of the human embryonic stem cells to Matrigel resulted in highest survival rates. For passage of the cultures on the other hand, enzymatic dissociation was found to be most efficient. In addition, this method reduces the time, work, and skills needed for propagation of the human embryonic stem cells. With the present protocol, the human embryonic stem cells have been cultured under feeder-free conditions for up to 35 passages while maintaining a normal karyotype, stable proliferation rate, and high telomerase activity. Furthermore, the feeder-free human embryonic stem cell cultures express the transcription factor Oct-4, alkaline phosphatase, and cell surface markers SSEA-3, SSEA-4, Tra 1-60, Tra 1-81, and formed teratomas in severe combined immunodeficient mice. This method provides distinct advantages compared with previous protocols and make propagation of human embryonic stem cells less laborious and more efficient.
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Affiliation(s)
- Eva Sjögren-Jansson
- Department of Clinical Chemistry and Transfusion Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden
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111
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Tang Z, Sun Y, Harley SE, Zou H, Yu H. Human Bub1 protects centromeric sister-chromatid cohesion through Shugoshin during mitosis. Proc Natl Acad Sci U S A 2004; 101:18012-7. [PMID: 15604152 PMCID: PMC539817 DOI: 10.1073/pnas.0408600102] [Citation(s) in RCA: 192] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Sister chromatids in mammalian cells remain attached mostly at their centromeres at metaphase because of the loss of cohesion along chromosome arms in prophase. Here, we report that Bub1 retains centromeric cohesion in mitosis of human cells. Depletion of Bub1 or Shugoshin (Sgo1) in HeLa cells by RNA interference causes massive missegregation of sister chromatids that originates at centromeres. Surprisingly, loss of chromatid cohesion in Bub1 and Sgo1 RNA-interference cells does not appear to require the full activation of separase but, instead, triggers a mitotic arrest that depends on Mad2 and Aurora B. Bub1 maintains the steady-state levels and centromeric localization of Sgo1. Therefore, Bub1 protects centromeric cohesion through Shugoshin in mitosis.
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Affiliation(s)
- Zhanyun Tang
- Department of Pharmacology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9041, USA
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112
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Ladon D, Doherty A, Newson R, Turner J, Bhamra M, Case CP. Changes in metal levels and chromosome aberrations in the peripheral blood of patients after metal-on-metal hip arthroplasty. J Arthroplasty 2004; 19:78-83. [PMID: 15578558 DOI: 10.1016/j.arth.2004.09.010] [Citation(s) in RCA: 151] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
A prospective study was performed to investigate changes in metal levels and chromosome aberrations in patients within 2 years of receiving metal-on-metal hip arthroplasties. There was a statistically significant increase of cobalt and chromium concentrations, with a small increase in molybdenum, in whole blood at 6, 12, and 24 months after surgery. There was also a statistically significant increase of both chromosome translocations and aneuploidy in peripheral blood lymphocytes at 6, 12, and 24 months after surgery. The changes were generally progressive with time, but the change in aneuploidy was much greater than in chromosome translocations. No statistically significant correlations were found in secondary analyses between chromosome translocation indices and cobalt or chromium concentration in whole blood. Although the clinical consequences of these changes, if any, are unknown, future epidemiological studies could usefully include direct comparisons of patients with implants of different composition.
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Affiliation(s)
- Dariusz Ladon
- University of Bristol, Orthopaedic Surgery, BIRC-Bristol Implant Research Center, Bristol, UK
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113
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Bayani J, Squire JA. Preparation of Cytogenetic Specimens from Tissue Samples. ACTA ACUST UNITED AC 2004; Chapter 22:Unit 22.2. [DOI: 10.1002/0471143030.cb2202s23] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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114
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Akiyama Y, Conner JA, Goel S, Morishige DT, Mullet JE, Hanna WW, Ozias-Akins P. High-resolution physical mapping in Pennisetum squamulatum reveals extensive chromosomal heteromorphism of the genomic region associated with apomixis. PLANT PHYSIOLOGY 2004; 134:1733-41. [PMID: 15064383 PMCID: PMC419846 DOI: 10.1104/pp.103.033969] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2003] [Revised: 01/07/2004] [Accepted: 01/07/2004] [Indexed: 05/18/2023]
Abstract
Gametophytic apomixis is asexual reproduction as a consequence of parthenogenetic development of a chromosomally unreduced egg. The trait leads to the production of embryos with a maternal genotype, i.e. progeny are clones of the maternal plant. The application of the trait in agriculture could be a tremendous tool for crop improvement through conventional and nonconventional breeding methods. Unfortunately, there are no major crops that reproduce by apomixis, and interspecific hybridization with wild relatives has not yet resulted in commercially viable germplasm. Pennisetum squamulatum is an aposporous apomict from which the gene(s) for apomixis has been transferred to sexual pearl millet by backcrossing. Twelve molecular markers that are linked with apomixis coexist in a tight linkage block called the apospory-specific genomic region (ASGR), and several of these markers have been shown to be hemizygous in the polyploid genome of P. squamulatum. High resolution genetic mapping of these markers has not been possible because of low recombination in this region of the genome. We now show the physical arrangement of bacterial artificial chromosomes containing apomixis-linked molecular markers by high resolution fluorescence in situ hybridization on pachytene chromosomes. The size of the ASGR, currently defined as the entire hemizygous region that hybridizes with apomixis-linked bacterial artificial chromosomes, was estimated on pachytene and mitotic chromosomes to be approximately 50 Mbp (a quarter of the chromosome). The ASGR includes highly repetitive sequences from an Opie-2-like retrotransposon family that are particularly abundant in this region of the genome.
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Affiliation(s)
- Yukio Akiyama
- Department of Horticulture, University of Georgia, Tifton, Georgia 31793-0748, USA
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115
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Henegariu O, Heerema NA, Thurston V, Jung SH, Pera M, Vance GH. Characterization of gains, losses, and regional amplification in testicular germ cell tumor cell lines by comparative genomic hybridization. ACTA ACUST UNITED AC 2004; 148:14-20. [PMID: 14697636 DOI: 10.1016/s0165-4608(03)00211-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
We have performed comparative genomic hybridization on 12 testicular germ cell tumor (TGCT) cell lines and one paraffin-embedded surgical specimen to identify and characterize genome-wide gains and losses of chromosomes in these specimens. All specimens demonstrated overrepresentation of 12p. Other significant chromosomal gains, apart from 12p, included the X chromosome and chromosome arms 1q and 20q. Chromosomal losses were observed for chromosomes 4 and 18 and chromosome arms 2q, 9q, and 13q. Genomic differences were observed between an embryonal carcinoma component of a mixed tumor, 833K, and its cisplastin-resistant derivative line, 64CP, including losses of 6q23 approximately qter and 9p22 approximately q21. Five lines also demonstrated gain of 12p and additional 12p12 approximately p13 material. Similarly, two lines demonstrated gain of 12p and additional 12p11.2 approximately p12 material. The data supports the consistent gain of 12p in adult TGCT cell lines and additional regional amplification of 12p in some lines. This regional amplification has been observed in both primary tumor specimens and TGCT cell lines and may support a hypothesis that at least two different regions of 12p, one proximal and one distal, harbor genes important for the pathogenesis of testicular germ cell neoplasia.
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Affiliation(s)
- Octavian Henegariu
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06510, USA
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116
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Chai JH, Locke DP, Greally JM, Knoll JHM, Ohta T, Dunai J, Yavor A, Eichler EE, Nicholls RD. Identification of four highly conserved genes between breakpoint hotspots BP1 and BP2 of the Prader-Willi/Angelman syndromes deletion region that have undergone evolutionary transposition mediated by flanking duplicons. Am J Hum Genet 2003; 73:898-925. [PMID: 14508708 PMCID: PMC1180611 DOI: 10.1086/378816] [Citation(s) in RCA: 161] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2003] [Accepted: 08/01/2003] [Indexed: 01/21/2023] Open
Abstract
Prader-Willi and Angelman syndromes (PWS and AS) typically result from an approximately 4-Mb deletion of human chromosome 15q11-q13, with clustered breakpoints (BP) at either of two proximal sites (BP1 and BP2) and one distal site (BP3). HERC2 and other duplicons map to these BP regions, with the 2-Mb PWS/AS imprinted domain just distal of BP2. Previously, the presence of genes and their imprinted status have not been examined between BP1 and BP2. Here, we identify two known (CYFIP1 and GCP5) and two novel (NIPA1 and NIPA2) genes in this region in human and their orthologs in mouse chromosome 7C. These genes are expressed from a broad range of tissues and are nonimprinted, as they are expressed in cells derived from normal individuals, patients with PWS or AS, and the corresponding mouse models. However, replication-timing studies in the mouse reveal that they are located in a genomic domain showing asynchronous replication, a feature typically ascribed to monoallelically expressed loci. The novel genes NIPA1 and NIPA2 each encode putative polypeptides with nine transmembrane domains, suggesting function as receptors or as transporters. Phylogenetic analyses show that NIPA1 and NIPA2 are highly conserved in vertebrate species, with ancestral members in invertebrates and plants. Intriguingly, evolutionary studies show conservation of the four-gene cassette between BP1 and BP2 in human, including NIPA1/2, CYFIP1, and GCP5, and proximity to the Herc2 gene in both mouse and Fugu. These observations support a model in which duplications of the HERC2 gene at BP3 in primates first flanked the four-gene cassette, with subsequent transposition of these four unique genes by a HERC2 duplicon-mediated process to form the BP1-BP2 region. Duplicons therefore appear to mediate genomic fluidity in both disease and evolutionary processes.
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Affiliation(s)
- J-H Chai
- Center for Neurobiology and Behavior, Department of Psychiatry, University of Pennsylvania, Philadelphia, PA, 19104, USA
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117
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Koumbaris GL, Bass HW. A new single-locus cytogenetic mapping system for maize (Zea mays L.): overcoming FISH detection limits with marker-selected sorghum (S. propinquum L.) BAC clones. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2003; 35:647-659. [PMID: 12940957 DOI: 10.1046/j.1365-313x.2003.01829.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The development of a cytogenetic map for maize (Zea mays L.) is shown to be feasible by means of a combination of resources from sorghum and oat that overcome limitations of single-copy gene detection. A maize chromosome-addition line of oat, OMAd9.2, provided clear images of optically isolated pachytene chromosomes through a chromosome spread and painting technique. A direct labeled oligonucleotide fluorescence in situ hybridization (FISH) probe MCCY specifically stained the centromere. The arm ratio (long/short) for maize chromosome 9 in the addition line was 1.7, comparable to the range of 1.6-2.1 previously reported for maize chromosome 9. A sorghum (Sorghum propinquum L.) BAC library was screened by hybridization with each of three maize core-bin-marker (CBM) probes: umc109 (CBM9.01), umc192/bz1 (CBM9.02), and csu54b (CBM9.08). A single BAC clone for each marker was chosen; designated sCBM9.1, sCBM9.2, or sCBM9.8; and used as a FISH probe on pachytene spreads from OMAd9.2. In each case, discrete FISH signals were observed, and their cytogenetic positions were determined to be 9S.79 (at position 79% of the length of chromosome 9 short arm) for sCBM9.1, 9S.65 for sCBM9.2, and approximately 9L.95 for sCBM9.8. These map positions were co-linear with linkage-map positions for these and other loci common to the linkage and cytogenetic maps. This work represents a major breakthrough for cytogenetic mapping of the maize genome, and also provides a general strategy that can be applied to cytogenetic mapping of other plant species with relatively large and complex genomes.
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Affiliation(s)
- George L Koumbaris
- Department of Biological Science, The Florida State University, Tallahassee, FL 32306-4370, USA
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118
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Mayr D, Amann G, Siefert C, Diebold J, Anderegg B. Does endometriosis really have premalignant potential? A clonal analysis of laser-microdissected tissue. FASEB J 2003; 17:693-5. [PMID: 12594178 DOI: 10.1096/fj.02-0562fje] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Since 1925, epidemiological and histological evidence for an association between endometriosis and ovarian neoplasia has accumulated. Recently, publications assaying the clonality of a given cell population have implied endometriosis has premalignant properties. However, the human androgen receptor used as a marker in these studies is of highly questionable reliability due to the instability of its methylation pattern in nonmalignant cells and during the course of malignancy. Therefore, we decided to readdress the question of clonality of endometriotic foci by using an alternative assay based on a polymorphism of the phosphoglycerate kinase-1 gene. We overcame the limitation to using ovarian cysts (a problem encountered in other studies) by laser-microdissecting defined tissue fractions of interest. From the 13/29 informative patients, a total of 32 endometriotic samples from various sites was assayed. Only 2/32 samples from different patients bore monoclonal tissue. With one of those cases, we present the first direct evidence of the two morphological endometric compartments comprising a single biphasic developmental unit. Neither monoclonal patient was characterized by any outstanding clinical parameters, including neoplasia. Individual endometriotic foci from the only patient in this study with neoplasia was assayed as being polyclonal. Therefore, former studies stating endometriosis as premalignant have to be cautiously reinterpreted.
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Affiliation(s)
- Doris Mayr
- Department of Pathology, Ludwig-Maximilians University Munich, D-80337 Munich, Germany
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119
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Arslantas A, Artan S, Oner U, Durmaz R, Müslümanoglu H, Atasoy MA, Başaran N, Tel E. Detection of chromosomal imbalances in spinal meningiomas by comparative genomic hybridization. Neurol Med Chir (Tokyo) 2003; 43:12-8; discussion 19. [PMID: 12568317 DOI: 10.2176/nmc.43.12] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Little is known about genetic mutations during the malignant progression of spinal meningiomas. This study investigated genomic changes across the entire genome in spinal meningioma samples to determine possible mechanism(s) of tumorigenesis. Paraffin-embedded tissue sections of 16 spinal meningiomas were analyzed by the comparative genomic hybridization (CGH) technique. Lymphocytes of the patients were evaluated as controls. Genomic change was detected in 11 samples. Complete or partial loss of chromosome 22 was the most commonly seen abnormality in eight cases. Chromosome losses on 1p, 9p, and 10q and gains on 5p and 17q were the other abnormalities. These changes are all frequently seen in meningiomas, but are mostly specific to atypical and anaplastic meningiomas. However, in the present study, copy number changes on chromosomes 9p (3 samples), 17q (2 samples), and 1p (2 samples) were seen even in the benign tumors. Our results suggest that in addition to the neurofibromatosis type 2 tumor suppressor gene, other cancer-related genes located on 1p, 9p, 10q, and 17q might be involved in the etiology of spinal meningiomas.
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Affiliation(s)
- Ali Arslantas
- Department of Neurosurgery, Osmangazi University Medical Faculty, Eskisehir, Turkey.
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120
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Deng W, Tsao SW, Lucas JN, Leung CS, Cheung ALM. A new method for improving metaphase chromosome spreading. Cytometry A 2003; 51:46-51. [PMID: 12500304 DOI: 10.1002/cyto.a.10004] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND The success of complex molecular cytogenetic studies depends on having properly spread chromosomes. However, inconsistency of optimum chromosome spreading remains a major problem in cytogenetic studies. METHODS The metaphase spreading process was carefully timed to identify the most critical phase of chromosome spreading. The effects of dropping height of cell suspension, slide condition, drying time, fixative ratio, and relative humidity on the quality of metaphase spreads were studied by quantitative examination of metaphase chromosome spreads. Normal and immortalized human epithelial ovarian cells, neuroblastoma cells, and normal lymphocytes were tested. RESULTS Humidity over the slide was the most important variable affecting the quality of chromosome spreads. Consistent improvement in chromosome spreading (larger metaphase area, less chromosome overlaps, or lower frequencies of broken metaphases) was obtained for all cell types if dynamic cell rehydration, occurring as fixative absorbs moisture from air, was made to coincide with the prompt fixation of spread chromosomes to the slide. This was achieved by dropping cells on dry glass slides placed in a shallow metal tray and then quickly lowering the tray into a covered 50 degrees C water bath for slide drying. CONCLUSIONS A new and simple method for improving metaphase chromosome spreading was developed based on our study on the characteristics of chromosome spreading.
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Affiliation(s)
- Wen Deng
- Department of Anatomy, The University of Hong Kong, Hong Kong, SAR, China
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121
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Jeuken JWM, Sprenger SHE, Wesseling P. Comparative genomic hybridization: practical guidelines. DIAGNOSTIC MOLECULAR PATHOLOGY : THE AMERICAN JOURNAL OF SURGICAL PATHOLOGY, PART B 2002; 11:193-203. [PMID: 12459635 DOI: 10.1097/00019606-200212000-00002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Comparative genomic hybridization (CGH) is a technique used to identify copy number changes throughout a genome. Until now, hundreds of CGH studies have been published reporting chromosomal imbalances in a large variety of human neoplasms. Additionally, technical improvements of specific steps in a CGH experiment and reviews on the technique have appeared. However, full CGH protocols are only occasionally published. In this paper a review of CGH is presented, including technique, pitfalls, and difficulties. Our own protocol is completely described and discussed, including the different optimization experiments used to establish this protocol and points requiring special attention. Although this protocol results in reliable and sensitive CGH experiments in our hands, readers should keep in mind that other laboratories may prefer other protocols. Testing different options, among others, as discussed in the current paper generates the most appropriate protocol. This paper shows the complexity of the CGH technique and may serve as a guideline for starting CGH or as a troubleshooting guide for those who perform CGH.
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Affiliation(s)
- Judith W M Jeuken
- Department of Neurology, University Medical Center Nijmegen, The Netherlands.
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122
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Jiang F, Katz RL. Use of interphase fluorescence in situ hybridization as a powerful diagnostic tool in cytology. DIAGNOSTIC MOLECULAR PATHOLOGY : THE AMERICAN JOURNAL OF SURGICAL PATHOLOGY, PART B 2002; 11:47-57. [PMID: 11854602 DOI: 10.1097/00019606-200203000-00009] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Interphase fluorescence in situ hybridization (I-FISH) using labeled nucleic acid probes detects chromosomal and genetic aberrations at a cellular level. I-FISH is a relatively fast and sensitive technique for evaluating a large number of cells and revealing more specific information than other techniques. It has been proven to be an invaluable molecular test in cytologic analyses for the detection of subtle genetic alterations that correlate with disease progression. In this postgenomic era, with the draft of the human genome available and expansion of the knowledge of tumor-specific genetic changes, the application of I-FISH probes in cytologic analysis should be of great value in the early detection, risk assessment, and monitoring of therapy efficacy in cancer. Here, we outline the principle of the I-FISH procedure, present suggestions to efficiently analyze cytologic materials, provide examples of practical applications, and discuss new aspects of the technique.
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Affiliation(s)
- Feng Jiang
- Department of Pathology, The University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030, USA
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