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1.
BMJ ; 375: n2400, 2021 10 14.
Article in English | MEDLINE | ID: mdl-34649864

ABSTRACT

OBJECTIVE: To evaluate the effects of therapeutic heparin compared with prophylactic heparin among moderately ill patients with covid-19 admitted to hospital wards. DESIGN: Randomised controlled, adaptive, open label clinical trial. SETTING: 28 hospitals in Brazil, Canada, Ireland, Saudi Arabia, United Arab Emirates, and US. PARTICIPANTS: 465 adults admitted to hospital wards with covid-19 and increased D-dimer levels were recruited between 29 May 2020 and 12 April 2021 and were randomly assigned to therapeutic dose heparin (n=228) or prophylactic dose heparin (n=237). INTERVENTIONS: Therapeutic dose or prophylactic dose heparin (low molecular weight or unfractionated heparin), to be continued until hospital discharge, day 28, or death. MAIN OUTCOME MEASURES: The primary outcome was a composite of death, invasive mechanical ventilation, non-invasive mechanical ventilation, or admission to an intensive care unit, assessed up to 28 days. The secondary outcomes included all cause death, the composite of all cause death or any mechanical ventilation, and venous thromboembolism. Safety outcomes included major bleeding. Outcomes were blindly adjudicated. RESULTS: The mean age of participants was 60 years; 264 (56.8%) were men and the mean body mass index was 30.3 kg/m2. At 28 days, the primary composite outcome had occurred in 37/228 patients (16.2%) assigned to therapeutic heparin and 52/237 (21.9%) assigned to prophylactic heparin (odds ratio 0.69, 95% confidence interval 0.43 to 1.10; P=0.12). Deaths occurred in four patients (1.8%) assigned to therapeutic heparin and 18 patients (7.6%) assigned to prophylactic heparin (0.22, 0.07 to 0.65; P=0.006). The composite of all cause death or any mechanical ventilation occurred in 23 patients (10.1%) assigned to therapeutic heparin and 38 (16.0%) assigned to prophylactic heparin (0.59, 0.34 to 1.02; P=0.06). Venous thromboembolism occurred in two patients (0.9%) assigned to therapeutic heparin and six (2.5%) assigned to prophylactic heparin (0.34, 0.07 to 1.71; P=0.19). Major bleeding occurred in two patients (0.9%) assigned to therapeutic heparin and four (1.7%) assigned to prophylactic heparin (0.52, 0.09 to 2.85; P=0.69). CONCLUSIONS: In moderately ill patients with covid-19 and increased D-dimer levels admitted to hospital wards, therapeutic heparin was not significantly associated with a reduction in the primary outcome but the odds of death at 28 days was decreased. The risk of major bleeding appeared low in this trial. TRIAL REGISTRATION: ClinicalTrials.gov NCT04362085.


Subject(s)
Anticoagulants/therapeutic use , COVID-19/mortality , COVID-19/therapy , Heparin/therapeutic use , Hospitalization/statistics & numerical data , Respiration, Artificial , Biomarkers/blood , Female , Humans , Intensive Care Units/statistics & numerical data , Male , Middle Aged , SARS-CoV-2 , Severity of Illness Index
2.
medRxiv ; 2021 Jul 12.
Article in English | MEDLINE | ID: mdl-34268513

ABSTRACT

BACKGROUND: Heparin, in addition to its anticoagulant properties, has anti-inflammatory and potential anti-viral effects, and may improve endothelial function in patients with Covid-19. Early initiation of therapeutic heparin could decrease the thrombo-inflammatory process, and reduce the risk of critical illness or death. METHODS: We randomly assigned moderately ill hospitalized ward patients admitted for Covid-19 with elevated D-dimer level to therapeutic or prophylactic heparin. The primary outcome was a composite of death, invasive mechanical ventilation, non-invasive mechanical ventilation or ICU admission. Safety outcomes included major bleeding. Analysis was by intention-to-treat. RESULTS: At 28 days, the primary composite outcome occurred in 37 of 228 patients (16.2%) assigned to therapeutic heparin, and 52 of 237 patients (21.9%) assigned to prophylactic heparin (odds ratio, 0.69; 95% confidence interval [CI], 0.43 to 1.10; p=0.12). Four patients (1.8%) assigned to therapeutic heparin died compared with 18 patients (7.6%) assigned to prophylactic heparin (odds ratio, 0.22; 95%-CI, 0.07 to 0.65). The composite of all-cause mortality or any mechanical ventilation occurred in 23 (10.1%) in the therapeutic heparin group and 38 (16.0%) in the prophylactic heparin group (odds ratio, 0.59; 95%-CI, 0.34 to 1.02). Major bleeding occurred in 2 patients (0.9%) with therapeutic heparin and 4 patients (1.7%) with prophylactic heparin (odds ratio, 0.52; 95%-CI, 0.09 to 2.85). CONCLUSIONS: In moderately ill ward patients with Covid-19 and elevated D-dimer level, therapeutic heparin did not significantly reduce the primary outcome but decreased the odds of death at 28 days. Trial registration numbers: NCT04362085 ; NCT04444700.

3.
Trials ; 22(1): 202, 2021 Mar 10.
Article in English | MEDLINE | ID: mdl-33691765

ABSTRACT

OBJECTIVES: To determine the effect of therapeutic anticoagulation, with low molecular weight heparin (LMWH) or unfractionated heparin (UFH, high dose nomogram), compared to standard care in hospitalized patients admitted for COVID-19 with an elevated D-dimer on the composite outcome of intensive care unit (ICU) admission, non-invasive positive pressure ventilation, invasive mechanical ventilation or death up to 28 days. TRIAL DESIGN: Open-label, parallel, 1:1, phase 3, 2-arm randomized controlled trial PARTICIPANTS: The study population includes hospitalized adults admitted for COVID-19 prior to the development of critical illness. Excluded individuals are those where the bleeding risk or risk of transfusion would generally be considered unacceptable, those already therapeutically anticoagulated and those who have already have any component of the primary composite outcome. Participants are recruited from hospital sites in Brazil, Canada, Ireland, Saudi Arabia, United Arab Emirates, and the United States of America. The inclusion criteria are: 1) Laboratory confirmed COVID-19 (diagnosis of SARS-CoV-2 via reverse transcriptase polymerase chain reaction as per the World Health Organization protocol or by nucleic acid based isothermal amplification) prior to hospital admission OR within first 5 days (i.e. 120 hours) after hospital admission; 2) Admitted to hospital for COVID-19; 3) One D-dimer value above the upper limit of normal (ULN) (within 5 days (i.e. 120 hours) of hospital admission) AND EITHER: a. D-Dimer ≥2 times ULN OR b. D-Dimer above ULN and Oxygen saturation ≤ 93% on room air; 4) > 18 years of age; 5) Informed consent from the patient (or legally authorized substitute decision maker). The exclusion criteria are: 1) pregnancy; 2) hemoglobin <80 g/L in the last 72 hours; 3) platelet count <50 x 109/L in the last 72 hours; 4) known fibrinogen <1.5 g/L (if testing deemed clinically indicated by the treating physician prior to the initiation of anticoagulation); 5) known INR >1.8 (if testing deemed clinically indicated by the treating physician prior to the initiation of anticoagulation); 6) patient already prescribed intermediate dosing of LMWH that cannot be changed (determination of what constitutes an intermediate dose is to be at the discretion of the treating clinician taking the local institutional thromboprophylaxis protocol for high risk patients into consideration); 7) patient already prescribed therapeutic anticoagulation at the time of screening [low or high dose nomogram UFH, LMWH, warfarin, direct oral anticoagulant (any dose of dabigatran, apixaban, rivaroxaban, edoxaban)]; 8) patient prescribed dual antiplatelet therapy, when one of the agents cannot be stopped safely; 9) known bleeding within the last 30 days requiring emergency room presentation or hospitalization; 10) known history of a bleeding disorder of an inherited or active acquired bleeding disorder; 11) known history of heparin-induced thrombocytopenia; 12) known allergy to UFH or LMWH; 13) admitted to the intensive care unit at the time of screening; 14) treated with non-invasive positive pressure ventilation or invasive mechanical ventilation at the time of screening; 15) Imminent death according to the judgement of the most responsible physician; 16) enrollment in another clinical trial of antithrombotic therapy involving hospitalized patients. INTERVENTION AND COMPARATOR: Intervention: Therapeutic dose of LMWH (dalteparin, enoxaparin, tinzaparin) or high dose nomogram of UFH. The choice of LMWH versus UFH will be at the clinician's discretion and dependent on local institutional supply. Comparator: Standard care [thromboprophylactic doses of LMWH (dalteparin, enoxaparin, tinzaparin, fondaparinux)] or UFH. Administration of LMWH, UFH or fondaparinux at thromboprophylactic doses for acutely ill hospitalized medical patients, in the absence of contraindication, is generally considered standard care. MAIN OUTCOMES: The primary composite outcome of ICU admission, non-invasive positive pressure ventilation, invasive mechanical ventilation or death at 28 days. Secondary outcomes include (evaluated up to day 28): 1. All-cause death 2. Composite of ICU admission or all-cause death 3. Composite of mechanical ventilation or all-cause death 4. Major bleeding as defined by the ISTH Scientific and Standardization Committee (ISTH-SSC) recommendation; 5. Red blood cell transfusion (>1 unit); 6. Transfusion of platelets, frozen plasma, prothrombin complex concentrate, cryoprecipitate and/or fibrinogen concentrate; 7. Renal replacement therapy; 8. Hospital-free days alive; 9. ICU-free days alive; 10. Ventilator-free days alive; 11. Organ support-free days alive; 12. Venous thromboembolism (defined as symptomatic or incidental, suspected or confirmed via diagnostic imaging and/or electrocardiogram where appropriate); 13. Arterial thromboembolism (defined as suspected or confirmed via diagnostic imaging and/or electrocardiogram where appropriate); 14. Heparin induced thrombocytopenia; 15. Trajectories of COVID-19 disease-related coagulation and inflammatory biomarkers. RANDOMISATION: Randomisation will be stratified by site and age (>65 versus ≤65 years) using a 1:1 computer-generated random allocation sequence with variable block sizes. Randomization will occur within the first 5 days (i.e. 120 hours) of participant hospital admission. However, it is recommended that randomization occurs as early as possible after hospital admission. Central randomization using an interactive web response system will ensure allocation concealment. BLINDING (MASKING): No blinding involved. This is an open-label trial. NUMBERS TO BE RANDOMISED (SAMPLE SIZE): 462 patients (231 per group) are needed to detect a 15% risk difference, from 50% in the control group to 35% in the experimental group, with power of 90% at a two-sided alpha of 0.05. TRIAL STATUS: Protocol Version Number 1.4. Recruitment began on May 11th, 2020. Recruitment is expected to be completed March 2022. Recruitment is ongoing. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04362085 Date of Trial Registration: April 24, 2020 FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest of expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.


Subject(s)
Anticoagulants/therapeutic use , Blood Coagulation Disorders/drug therapy , COVID-19 Drug Treatment , Blood Coagulation Disorders/blood , Blood Coagulation Disorders/complications , COVID-19/blood , COVID-19/complications , COVID-19/physiopathology , Clinical Trials, Phase III as Topic , Fibrin Fibrinogen Degradation Products/metabolism , Heparin/therapeutic use , Heparin, Low-Molecular-Weight/therapeutic use , Hospitalization , Humans , Intensive Care Units/statistics & numerical data , Noninvasive Ventilation/statistics & numerical data , Pragmatic Clinical Trials as Topic , Randomized Controlled Trials as Topic , Respiration, Artificial/statistics & numerical data , SARS-CoV-2
4.
J Thromb Haemost ; 18(11): 2870-2877, 2020 11.
Article in English | MEDLINE | ID: mdl-33448602

ABSTRACT

BACKGROUND: Arterial thromboembolic events are relatively common and well-described in patients with thrombotic thrombocytopenic purpura (TTP). However, the literature describing venous thromboembolism (VTE) in TTP is scarce. METHODS: Single-institution retrospective chart review was conducted in TTP patients over a 10-year period to describe the point prevalence of VTE. Data were analyzed using descriptive statistics. RESULTS: We identified 77 consecutive patients with 123 episodes of TTP. Of these patients, 14 (18%) experienced 16 VTEs (6 pulmonary embolisms, 6 deep vein thromboses, 4 superficial vein thromboses [SVT]). Excluding SVT, the point prevalence of VTE was 14%. All were acute and associated with admission for acute TTP. All patients were treated with plasma exchange (PLEX); 6/8 patients on concurrent PLEX at VTE diagnosis were exchanged with solvent-detergent plasma (SDP). Platelet and lactate dehydrogenase levels at time of VTE diagnosis had largely normalized from presentation values (median 175 × 109 U/L [interquartile range 130.75, 250] and 232 U/L [interquartile range 178.75, 263.5], respectively). Most VTEs (9/16) occurred while patients were not on pharmacologic thromboprophylaxis. All but one VTE was treated with anticoagulation. No VTEs were fatal or massive. CONCLUSIONS: Our data provide additional evidence that TTP patients may be at risk for VTE. It is possible that SDP exerted a prothrombotic effect. TTP-associated VTEs may be pathophysiologically distinct from arterial thromboses because they occur following hematological recovery. VTE thromboprophylaxis was not commonly used. Our findings suggest the need to implement VTE thromboprophylaxis earlier in hospitalized patients with TTP.


Subject(s)
Purpura, Thrombotic Thrombocytopenic , Venous Thromboembolism , Anticoagulants , Humans , Prevalence , Purpura, Thrombotic Thrombocytopenic/diagnosis , Purpura, Thrombotic Thrombocytopenic/epidemiology , Purpura, Thrombotic Thrombocytopenic/therapy , Retrospective Studies , Venous Thromboembolism/diagnosis , Venous Thromboembolism/epidemiology
5.
Vox Sang ; 114(4): 363-373, 2019 May.
Article in English | MEDLINE | ID: mdl-30937914

ABSTRACT

BACKGROUND AND OBJECTIVES: Rare but potentially life-threatening hypersensitivity reactions can occur during the administration of intravenous iron. To provide guidance to healthcare professionals caring for adults receiving intravenous iron, a panel of 10 Canadian clinical experts developed a practical algorithm for the identification and management of hypersensitivity reactions to intravenous iron. MATERIALS AND METHODS: A systematic search of PubMed to February 2018 was performed. Articles related to hypersensitivity reactions were selected for review. The algorithm was developed during a 1-day live meeting based on the literature review and clinical expertise where evidence was lacking. The algorithm was then refined through an iterative process involving a web-based platform and virtual meetings. RESULTS: The algorithm provides guidance to healthcare professionals in preparing for and administering IV iron, as well as recognizing and managing hypersensitivity reactions to intravenous iron. Considerations for re-challenging patients who have experienced prior reactions are provided. CONCLUSION: Healthcare professionals who are involved in the care of patients receiving intravenous iron should be trained to anticipate, recognize and manage hypersensitivity reactions to intravenous iron to optimize patient care.


Subject(s)
Hematology/standards , Infusions, Intravenous/adverse effects , Iron/adverse effects , Adult , Algorithms , Anaphylaxis , Canada , Consensus , Female , Humans , Hypersensitivity , Internet , Iron/administration & dosage , Male , Patient Safety , Quality of Health Care , Societies, Medical
6.
Article in English | WPRIM (Western Pacific) | ID: wpr-632592

ABSTRACT

A patient with known prostatic cancer presented with left supraorbital swelling with proptosis and restricted eye movements on left eye. Contrast enhanced computed tomography scan revealed dural and bone metastases with soft tissue component extending to the left orbit. Serum prostate specific antigen was markedly elevated at >100 ng/ml. Incision biopsy of the orbital tumor revealed only lymphocytic inflammatory cells within the fibrous stroma attributed mainly to the deeper location of the tumor or shallow locus of the biopsy. Incisional biopsy of the frontal bone revealed atypical looking cells in sheet cluster with nuclear enlargement, hyperchromatic in irregularity confirming the diagnosis of orbital metastasis of prostate carcinoma.Metastasis of prostate cancer to the orbit is rare. One should have a high index of suspicion of orbital metastasis when presented with an elderly patient with ocular symptoms and a history of prostate adenocarcinoma. A thorough clinical, radiological and histological evaluation is necessary to establish the diagnosis.


Subject(s)
Humans , Male , Aged , Neoplasm Metastasis , Adenocarcinoma , Prostatic Neoplasms , Eye , Tomography Scanners, X-Ray Computed
7.
Chromosoma ; 115(6): 459-67, 2006 Dec.
Article in English | MEDLINE | ID: mdl-16897100

ABSTRACT

Osteosarcoma (OS) is characterized by chromosomal instability and high copy number gene amplification. The breakage-fusion-bridge (BFB) cycle is a well-established mechanism of genome instability in tumors and in vitro models used to study the origins of complex chromosomal rearrangements and cancer genome amplification. To determine whether the BFB cycle could be increasing the de novo rate of formation of cytogenetic aberrations in OS, the frequency of anaphase bridge configurations and dicentric chromosomes in four OS cell lines was quantified. An increased level of anaphase bridges and dicentrics was observed in all the OS cell lines. There was also a strong association between the frequencies of anaphase bridges, dicentrics, centrosomal anomalies, and multipolar mitotic figures in all the OS cell lines, indicating a possible link in the mechanisms that led to the structural and numerical instabilities observed in OS. In summary, this study has provided strong support for the role of the BFB cycle in generating the extensive structural chromosome aberrations, as well as cell-to-cell cytogenetic variation observed in OS, thus conferring the genetic diversity for OS tumor progression.


Subject(s)
Bone Neoplasms/genetics , Chromosome Breakage , Gene Fusion , Genetic Heterogeneity , Osteosarcoma/genetics , Anaphase , Autoantigens/metabolism , Bone Neoplasms/pathology , Centromere Protein A , Chromosomal Instability , Chromosomal Proteins, Non-Histone/metabolism , Chromosome Painting , Chromosomes, Human , Humans , Kinetochores/metabolism , Osteosarcoma/pathology , Tumor Cells, Cultured
8.
Genes Chromosomes Cancer ; 42(4): 392-403, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15660435

ABSTRACT

Osteosarcoma (OS) is characterized by chromosomal instability and high-copy-number gene amplification. The breakage-fusion-bridge (BFB) cycle is a well-established mechanism of genomic instability in tumors and in vitro models used to study the origins of complex chromosomal rearrangements and cancer genome amplification. However, until now, there have been no high-resolution cytogenetic or genomic array studies of BFB events in OS. In the present study, multicolor banding (mBAND) FISH and submegabase resolution tiling set (SMRT) array comparative genomic hybridization (CGH) were used to identify and map genomic signatures of BFB events in four OS cell lines and one patient tumor. The expected intermediates associated with BFB-dicentric chromosomes, inverted duplications, and intra- and interchromosomal amplifications-were identified. mBAND analysis provided detailed mapping of rearrangements in 1p, 6p, and 8q and showed that translocation junctions were often in close proximity to fragile sites. More detailed mBAND studies of OS cell line MG-63 revealed ladderlike FISH signals of equally spaced interchromosomal coamplifications of 6p21, 8q24, and 9p21-p22 in a homogeneously staining region (hsr). Focal amplifications that concordantly mapped to the hsr were localized to discrete genomic intervals by SMRT array CGH. The complex amplicon structure in this hsr suggests focal amplifications immediately adjacent to microdeletions. Moreover, the genomic regions in which there was deletion/amplification had a preponderance of fragile sites. In summary, this study has provided further support for the role of the BFB mechanism and fragile sites in facilitating gene amplification and chromosomal rearrangement in OS.


Subject(s)
Gene Amplification , Gene Deletion , Nucleic Acid Hybridization , Osteosarcoma/genetics , Cell Line, Tumor , Chromosomes, Human, Pair 6 , Chromosomes, Human, Pair 8 , Humans , Molecular Probes , Oligonucleotide Array Sequence Analysis , Osteosarcoma/pathology , Peptide Nucleic Acids , Translocation, Genetic
9.
Cancer Genet Cytogenet ; 153(2): 158-64, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15350306

ABSTRACT

The advancement of fluorescence in situ hybridization-based assays has permitted more refined delineation of chromosomal loci involved in complex chromosomal rearrangements (CCRs) and gene amplification. In this detailed molecular cytogenetic analysis, spectral karyotyping (SKY), multicolor banding (mBAND) analysis, and microarray comparative genomic hybridization (CGH) were used to refine the analysis of chromosomes with amplifications and small intrachromosomal rearrangements such as inverted duplications and interstitial deletions present in the osteosarcoma cell line MG-63. SKY analysis has limited resolving power to delineate cryptic chromosomal rearrangements, so mBAND assays were performed for a subset of chromosomes (i.e., 6, 8, 17, and 20). Of the 10 clonal CCRs analyzed in detail with mBAND, 5 were found to have rearrangements between 8q24 and either 6p23 approximately pter or 6p21, with multiple copies of this translocation inserted at various sites in the different chromosomes. In two CCRs, 6p21 and 8q24 generated an alternating pattern of mBAND probe hybridization, indicating the presence of a large coamplified repeat unit within homogeneously staining regions. Microarray CGH analysis demonstrated focal high-level amplification of 8q23 approximately q24, 6p22 approximately pter, and 6p21, in agreement with the pattern of chromosome subband gains identified with mBAND. Thus, sequential SKY, mBAND, and microarray CGH provided a comprehensive description of some of the intricate chromosomal aberrations present in the complex MG-63 karyotype and permitted reconstruction of the fine structure of the genomic rearrangements, thus providing some important mechanistic clues concerning the details of the amplification process in tumors.


Subject(s)
Bone Neoplasms/genetics , Chromosome Banding , Gene Amplification/genetics , Gene Rearrangement/genetics , Karyotyping , Oligonucleotide Array Sequence Analysis/methods , Osteosarcoma/genetics , Cell Line, Tumor , Chromosome Mapping , Humans , Nucleic Acid Hybridization/methods
10.
Am J Pathol ; 164(1): 285-93, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14695341

ABSTRACT

Metaphase-based comparative genomic hybridization (CGH) has identified recurrent regions of gain on different chromosomes in bladder cancer, including 6p22. These regions may contain activated oncogenes important in disease progression. Using quantitative multiplex polymerase chain reaction (QM-PCR) to study DNA from 59 bladder tumors, we precisely mapped the focal region of genomic gain on 6p22. The marker STS-X64229 had copy number increases in 38 of 59 (64%) tumors and the flanking markers, RH122450 and A009N14, had copy number gains in 33 of 59 (56%) and 26 of 59 (45%) respectively. Contiguous gain was present for all three markers in 14 of 59 (24%) and for two (RH122450 and STS-X64229) in 25 of 59 (42%). The genomic distance between the markers flanking STS-X64229 is 0.5 megabases, defining the minimal region of gain on 6p22. Locus-specific interphase fluorescence in situ hybridization confirmed the increased copy numbers detected by QM-PCR. Current human genomic mapping data indicates that an oncogene, DEK, is centrally placed within this minimal region. Our findings demonstrate the power of QM-PCR to narrow the regions identified by CGH to facilitate identifying specific candidate oncogenes. This also represents the first study identifying DNA copy number increases for DEK in bladder cancer.


Subject(s)
Carcinoma/genetics , Chromosomes, Human, Pair 6/genetics , DNA, Neoplasm/analysis , Gene Amplification , Urinary Bladder Neoplasms/genetics , Adult , Aged , Aged, 80 and over , Female , Gene Dosage , Gene Expression Profiling , Humans , In Situ Hybridization, Fluorescence , Male , Middle Aged , Neoplasm Staging , Polymerase Chain Reaction
11.
Article in English | WPRIM (Western Pacific) | ID: wpr-632383

ABSTRACT

Methods: This is an experimental study of 12 rabbits implanted with ostrich eggshell (6 rabbits with 5mm- and 6 rabbits with 10mm-diameter grafts) subperiosteally in the right orbital floor. The right orbit was harvested en bloc 1, 2, and 3 months after onlay. Radiographic studies were done one day after implantation and prior to harvest. The specimens were submitted for gross and microscopic studies. Results: All animals showed normal wound healing. The grafts were stable and no foreign body reaction was observed 1, 2 and 3 months postimplantation. The size of the ostrich eggshell implants remained the same. There was no change in radiodensity at 3 months observation. Conclusion: The results of this study support the potential application of ostrich eggshell as bone substitute for orbital floor fractures.


Subject(s)
Rabbits , Animals , Struthioniformes , Bone Transplantation , Transplants , Orbit , Orbital Fractures
12.
Genes Chromosomes Cancer ; 38(3): 215-25, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14506695

ABSTRACT

Conventional cytogenetic and comparative genomic hybridization (CGH) studies have shown that osteosarcomas (OSs) are characterized by complex structural and numerical chromosomal alterations and gene amplification. In this study, we used high-resolution CGH to investigate recurrent patterns of genomic imbalance by use of DNA derived from nine OS tumors hybridized to a 19,200-clone cDNA microarray. In six OSs, there was copy number gain or amplification of 6p, with a minimal region of gain centering on segment 6p12.1. In seven OSs, the pattern of amplification affecting chromosome arm 8q showed high-level gains of 8q12-21.3 and 8q22-q23, with amplification of the MYC oncogene at 8q24.2. Seven OSs showed copy number gain or amplification of 17p between the loci bounded by GAS7 and PMI (17p11.2-17p12), and three of these tumors also showed small losses at 17p13, including the region containing TP53. An in silico analysis of the distribution of segmental duplications (duplicons) in this region identified a large number of tracts consisting of paralogous sequences mapping to the 17p region, encompassing the region of deletions and amplifications in OS. Interestingly, within this same region there were clusters of duplicons and several genes that are expressed during bone morphogenesis and in OS. In summary, microarray CGH analysis of the chromosomal imbalances of OS confirm the overall pattern observed by use of metaphase CGH and provides a more precise refinement of the boundaries of genomic gains and losses that characterize this tumor.


Subject(s)
Bone Neoplasms/genetics , Chromosome Deletion , Chromosome Mapping/methods , Gene Amplification/genetics , Oligonucleotide Array Sequence Analysis/methods , Osteosarcoma/genetics , Adolescent , Allelic Imbalance/genetics , Cell Line, Tumor , Child , Chromosome Aberrations , Chromosomes, Human, Pair 17/genetics , Chromosomes, Human, Pair 8/genetics , DNA, Neoplasm/genetics , Female , Genes, Duplicate/genetics , Genes, Neoplasm/genetics , Genomic Instability/genetics , Humans , Male , Neuroblastoma/genetics , Neuroblastoma/pathology , Nucleic Acid Hybridization
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