Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Cytogenetics”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 811 records · Page 45Linked to original sources
PubMed1996

A possible correlation between interferon-stimulated gene expression and cytogenetic responses in chronic myelogenous leukemia patients treated with alpha-interferon.

We studied the expression of the interferon-stimulated genes (ISGs), ISG-54 and 2',5'-oligoadenylate synthetase (2'-5' OAS), using the reverse transcription-polymerase chain reaction in 22 patients with chronic myelogenous leukemia (CML), who were treated with alpha-interferon (alpha-IFN). At the time of diagnosis, 7 patients (31.8%) showed no detectable expression of either gene, whereas 8 expressed both. The remaining 7 expressed neither ISG-54 nor 2'-5' OAS. After alpha-IFN treatment, 5 of the 7 CML patients who had not previously express ISGs expressed either ISG-54 or 2'5' OAS or both and 6 of the 7 who had previously expressed either ISG-54 or 2'-5' OAS expressed both. Three of the 7 (42.9%) CML patients who expressed both genes before and after alpha-IFN administration showed cytogenetic responses, as did 6 of the 11 (54.5%) in whom ISG expression was induced. In contrast, cytogenetic responses occurred in none of the patients in whom ISG expression was not induced. These results suggest that induction of ISG-54 and 2'-5' OAS expression by alpha-IFN may be an indicator of cytogenetic responses and, therefore, of value for monitoring CML patients.

2',5'-Oligoadenylate Synthetase↗
PubMed1999

Parachordoma is immunohistochemically and cytogenetically distinct from axial chordoma and extraskeletal myxoid chondrosarcoma.

Parachordoma is a rare soft-tissue tumor resembling extraskeletal myxoid chondrosarcoma and chordoma. Because fewer than 30 cases have been reported and precisely characterized, we studied the clinicopathologic features of seven new cases, comparing the immunohistochemical (six cases) and cytogenetic (one case) profiles with 15 cases of chordoma and six cases of extraskeletal myxoid chondrosarcoma. Patients with these tumors ranged in age from 7 to 62 years (mean, 35 years) and included four women and three men. The tumors presented as subfascial masses of the thigh (two cases), arm (three cases), chest wall (one cases), and buttocks (one case). In six of seven cases, there was neither recurrence nor metastasis within the follow-up, which ranged from 4 months to 7 years. The tumors were composed of vague nodules of large, rounded eosinophilic cells embedded in a matrix that varied from myxoid to densely hyaline, and the latter areas occasionally resembled primitive cartilage. Transitions between the large eosinophilic cells and smaller rounded and shorter spindled ones were often noted. Multivacuolated (physaliferouslike) cells were noted in all cases but were usually few in number. The matrix stained with Alcian blue (pH 2.5), and this staining was abolished with hyaluronidase predigestion. Immunohistochemistry for a variety of cytokeratins (CKs) (8/18, 1/10, 7, and 20), epithelial membrane antigen (EMA), S-100 protein, vimentin CD34, type IV collagen, smooth muscle actin, smooth muscle myosin heavy chain, calponin, and glial fibrillary acid protein was performed. All parachordomas strongly expressed CK 8/18, but not the other cytokeratins. Additionally, they expressed EMA (five of six). S-100 protein (six of six), and vimentin (six of six) and had a linear pattern of type IV collagen immunoreactivity around nests of cells (four of five). Calponin was noted in one case, but no cases expressed smooth muscle actin, smooth muscle myosin heavy chain, or glial fibrillary acid protein. In contrast, chordoma expressed CK 8/18 (15 of 15) and CK 1/10 (14 of 15), whereas extraskeletal myxoid chondrosarcoma consistently lacked CK. Although chordoma and extraskeletal myxoid chondrosarcoma showed considerable overlap with parachordoma, with respect to EMA and S-100 protein, they infrequently displayed type IV collagen, as was seen in parachordoma. One case of parachordoma studied cytogenetically disclosed trisomy 15, and monosomies of 1, 16, and 17 in contrast to the t(9;22) reported in extraskeletal myxoid chondrosarcoma and the monosomies of 3, 4, 10, and 13 seen in chordoma. We conclude that the immunohistochemical and cytogenetic profile distinguishes parachordoma from extraskeletal myxoid chondrosarcoma and chordoma. Lack of myoepithelial markers, furthermore, suggests parachordoma is not a deeply situated adnexal tumor. Because of these differences, parachordoma is best regarded as a distinct lesion without a clear relationship to other well-characterized tumors.

Adolescent↗
PubMed1996

Cytogenetics and experimental models.

Cytogenetic analysis plays a direct, potentially decisive role in the examination of benign and malignant bond and soft tissue tumors. Translocations, or the exchange of chromosomal material between two or more nonhomologous chromosomes, are frequently encountered as tumor-specific anomalies in mesenchymal neoplasms. The consequences of many of these translocations has been the formation of chimeric proteins with features characteristic of altered transcription factors. Recent studies have revealed new tumor-specific translocations (eg, cemento-ossifying fibroma and myxoid chondrosarcoma) and the association of established translocations, eg, t(11;22) and t(12;16), in rare histologic subtypes such as biphenotypic sarcomas with myogenic and with neural differentiation and round cell liposarcoma, respectively. In contrast to a single translocation, many mesenchymal neoplasms such as malignant fibrous histiocytoma and osteosarcoma are characterized by multiple, often complex, chromosomal abnormalities. Recent advances in molecular cytogenetics, eg, in situ hybridization and comparative genomic hybridization, have made the identification of many of these abnormalities possible and in some instances, have revealed chromosomal imbalances not detectable with traditional cytogenetic analysis.

Chromosome Aberrations↗
PubMed2000

Cytogenetics and cancer.

Techniques based on fluorescence in situ hybridization (FISH) have bridged the gap between molecular genetics and conventional cytogenetics. Since its introduction in the late 1980s, advanced FISH-based methods have greatly enhanced the cytogenetic analysis of hematopoietic and solid tumors and are rapidly gaining ground in clinical cytogenetic diagnostics. As interest in FISH technologies has grown, it has inspired an era of new FISH-based technologies such as multiplex FISH, spectral karyotyping, and comparative genomic hybridization. In this review, the focus is on the impact of these technologies in the field of cancer genetics.

Chromosome Aberrations↗
PubMed1994

Correlation of cytogenetic and fluorescence in situ hybridization (FISH) studies in normal and gliotic brain.

In vitro tissue culturing, for karyotype analysis, may introduce artifacts confounding the cytogenetic evaluation of tissues with low baseline proliferative activity. Utilizing a panel of fluorescence in situ hybridization (FISH) probes for chromosomes 7, 8, 9, 10, 12, 17, 18, X, and Y, we compared the results of FISH analysis of non-tumorous normal (11 patients) and gliotic (10 patients) brain tissue touch preparations with those of cytogenetic evaluation performed on short-term primary cultures of the same material. We found a significant rate of apparent monosomy of chromosomes 8 and 17 by FISH analysis, with no corresponding clonal chromosomal loss detected by karyotype evaluation. These monosomy rates were significantly lower in gliotic than in normal brain tissue, and image analysis suggested that this apparent monosomy was due to interphase pairing of homologous centromere signals. Two distinct Y-chromosome signals were seen in 9.4% of nuclei by FISH, with 3 of 15 males displaying disomy Y rates over 15%. Disomy Y rates correlated approximately with age and clonal disomy Y was seen in the karyotype of one of these specimens. Karyotype analysis demonstrated loss of a sex chromosome in 6 specimens, while no sex chromosome nullisomy was detected by FISH. FISH is a valuable adjunct to the cytogenetic evaluation of tissues with low baseline proliferative activity. The differences in relative monosomy rates between normal and gliotic brain suggest that alterations in nuclear architecture and/or DNA sequence accompany the transition from normal to reactive glia.

Aged↗
PubMed1997

Molecular cytogenetics of brain tumors.

Molecular cytogenetics includes a spectrum of methodologies that use molecular reagents to better define chromosomal alterations in normal and neoplastic cells. Brain tumors are a group of neoplasms for which there is a wealth of cytogenetic and molecular genetic information, and some of the newer techniques have extended the types of samples from which genetic information which can be obtained to biopsies and even paraffin-embedded sections. Fluorescence in situ hybridization on interphase nuclei has been used to confirm gains of chromosome 7, loss of chromosome 10, 9p deletion and gene amplification in malignant gliomas, and to visualize isochromosome 17q in medulloblastomas. Comparative genomic hybridization uses genomic DNA to determine gains and losses of chromosomes and chromosomal regions. This approach is particularly useful for identifying gene amplification. For cases in which chromosomal spreads are obtained, chromosomal painting is helpful in determining the origin of chromosomal segments. Several methods are now available in which each of the 22 autosomes and the sex chromosome can be identified by unique colors, termed Spectral karyotyping and multiplex-FISH. These molecular cytogenetic techniques are important clinical and experimental tools that have provided new insight into the genetic alterations of brain tumors.

Brain Neoplasms↗
PubMed2005

Application of ROMA (representational oligonucleotide microarray analysis) to patients with cytogenetic rearrangements.

PURPOSE: To demonstrate the accuracy and sensitivity of Representational Oligonucleotide Microarray Analysis (ROMA) to describe copy number changes in patients with chromosomal abnormalities. METHODS: ROMA was performed using BglII digested DNA from two cases with cytogenetically detected deletions and one case with an unbalanced terminal rearrangement detected only by subtelomeric FISH. Hybridization was to an 85,000-probe oligonucleotide microarray, providing an average resolution of 35 kb. FISH was used to confirm some of the ROMA findings. RESULTS: By ROMA, a del(13)(q14.3q21.2) was shown to be noncontiguous, with deletions extending from 53.08 to 61.40 Mb and from 72.88 to 74.83 Mb. The 10-Mb deletion contained only six known genes. FISH confirmed the noncontiguous nature of the deletion, as well as a small amplification in 6q that was also found in the patient's mother. A del(4)(q12q21.2) was found by ROMA to be 23 Mb in length, from 58.8 to 81.9 Mb on chromosome 4, in agreement with the cytogenetically assigned breakpoints. ROMA showed that an unbalanced "subtelomeric" rearrangement involved a 6-Mb deletion of 22q and an 8-Mb duplication of 16q. CONCLUSIONS: ROMA can define cytogenetic aberrations with extraordinary precision. Unexpected findings included the interrupted nature of the deletion in 13q and the large size of the imbalances in the "subtelomeric" rearrangement. Together with the information from the human genome sequence and proteomics, the ability to define rearrangements with "ultra-high" resolution will improve the ability to provide accurate prognosis both prenatally and postnatally to parents of offspring with chromosomal aberrations.

Child, Preschool↗
PubMedDate not supplied

Development and validation of a CGH microarray for clinical cytogenetic diagnosis.

PURPOSE: We developed a microarray for clinical diagnosis of chromosomal disorders using large insert genomic DNA clones as targets for comparative genomic hybridization (CGH). METHODS: The array contains 362 FISH-verified clones that span genomic regions implicated in over 40 known human genomic disorders and representative subtelomeric clones for each of the 41 clinically relevant human chromosome telomeres. Three or four clones from almost all deletion or duplication genomic regions and three or more clones for each subtelomeric region were included. We tested chromosome microarray analysis (CMA) in a masked fashion by examining genomic DNA from 25 patients who were previously ascertained in a genetic clinic and studied by conventional cytogenetics. A novel software package implemented in the R statistical programming language was developed for normalization, visualization, and inference. RESULTS: The CMA results were entirely consistent with previous cytogenetic and FISH findings. For clone by clone analysis, the sensitivity was estimated to be 96.7% and the specificity was 99.1%. Major advantages of this selected human genome array include the following: interrogation of clinically relevant genomic regions, the ability to test for a wide range of duplication and deletion syndromes in a single analysis, the ability to detect duplications that would likely be undetected by metaphase FISH, and ease of confirmation of suspected genomic changes by conventional FISH testing currently available in the cytogenetics laboratory. CONCLUSION: The array is an attractive alternative to telomere FISH and locus-specific FISH, but it does not include uniform coverage across the arms of each chromosome and is not intended to substitute for a standard karyotype. Limitations of CMA include the inability to detect both balanced chromosome changes and low levels of mosaicism.

Chromosome Aberrations↗
PubMed2005

Molecular heterogeneity and prognostic biomarkers in adults with acute myeloid leukemia and normal cytogenetics.

PURPOSE OF REVIEW: Patients with acute myeloid leukemia (AML) and normal karyotype constitute the single largest cytogenetic group of AML, estimated to account for 45% of adults with de novo AML. This article critically reviews the recent literature that addresses the molecular heterogeneity of this group of patients and how this relates to prognostic stratification and novel therapeutic approaches. RECENT FINDINGS: Four prognostic biomarkers-the internal tandem duplication and point mutations in the FLT3 gene, partial tandem duplication of the MLL gene, mutations of the CEBPA gene, and overexpression of the BAALC gene-have been found to predict outcome in patients with AML and normal cytogenetics. In addition, one study using gene expression profiling identified two subgroups of AML patients with a normal karyotype whose survival differs significantly. Because mutations in FLT3 result in an autophosphorylated, leukemogenesis-driving protein, molecular targeting therapy with a new class of tyrosine kinase inhibitors is being explored in early clinical trials. SUMMARY: Considerable progress has been made in molecular characterization of AML patients with normal cytogenetics. The challenge for the future is to incorporate these biologic discoveries into novel risk-adapted therapeutic strategies that will improve the currently disappointing cure rate (approximately 25-40%) of this group of patients.

Adult↗
PubMed1979

Electronic data processing in the Danish cytogenetic central register and EDP problems of registers in general.

A brief introduction to the Danish Cytogenetic Central Register (DCCR) is given, and possibilities, principles and problems concerning the establishment and maintenance of a national cytogenetic register are presented. Various data carrier media for registers in general are discussed, of which the magnetic disc is considered most appropriate. General principles for programs capable of performing insertions, deletions and other modifications in the data base are outlined as well as the principles for the programs in the DCCR. The individual records should preferably be identified by aid of a central person registration number (CPR) rather than by name. The data should be stored and sorted by this identification in order to facilitate retrieval of a desired record. The structure of the records is discussed with regard to prevention of the occurrence of certain errors as well as the optimization of processing. Flexibility and economy of space are achieved by using programs able to handle records of unequal length, and problems occurring in connection with this are discussed. The question of how to protect sensitive data is dealt with, and two different methods used in the DCCR are outlined. Programs capable of analyzing karyotypes with the purpose of recognizing various cytogenetic syndromes have been developed for use in the DCCR. Various examples of computing times of typical program runs are presented.

Chromosome Aberrations↗
PubMed1990

Breast cancer cytogenetics and beyond.

It is hypothesized that cancers arise as a result of genetic or chromosomal alteration. Evidence for this is provided by the leukaemias and lymphomas in which cytogenetic studies are of established value in diagnosis, classification and follow-up. In contrast, the cytogenetic study of all solid tumours, including breast carcinoma, is in its infancy. However, cytogenetic studies indicate that clonal structural alterations do occur, affecting several loci on a number of chromosomes. Molecular studies provide further evidence of recurring chromosomal breakpoints in breast cancer. This paper reviews the chromosomal rearrangements observed to date and discusses their relevance to the biology of breast cancer.

Breast Neoplasms↗
PubMed2004

Cytogenetic and hematological spontaneous remission in a case of acute myelogenous leukemia.

Several cases of spontaneous remission (SR) interrupting the invariably progressive course of untreated acute myeloblastic leukemia (AML) have been reported so far. We shall add to this series the hematological and cytogenetic SR occurring in a 72-yr-old man affected by AML following myelodysplastic syndrome. At diagnosis cytogenetic analysis showed the 48, xy, del (6) (p22-pter), +13, +14 karyotype. Owing to a lobar pneumonia, the chemotherapy was deferred and a broad spectrum antibiotic therapy was established. Supportive care included red cells and platelet transfusions and low-dose corticosteroid. Two months later, after the pneumonia had completely disappeared, a complete remission, lasting about 5 months, was documented on bone marrow morphological and cytogenetical examination, although some degree of myeloid dysplasia persisted. Possible mechanisms of the various SRs described during the course of AML are discussed with a review of the literature.

Adrenal Cortex Hormones↗
PubMed2006

Prospective study of 174 de novo acute myelogenous leukemias according to the WHO classification: subtypes, cytogenetic features and FLT3 mutations.

We report a prospective study of 174 unselected adult de novo acute myeloid leukemia (AML) cases diagnosed using the WHO classification. Of those, 57 (33%) were AML with recurrent cytogenetic abnormalities, 41 were (24%) AML with multilineage dysplasia, 74 (42%) were AML not otherwise categorized, and two were acute leukemias of ambiguous lineage. Clonal cytogenetic abnormalities were detected in 64% of the WHO AML cases with t(15;17) (15%), t(8;21) (12%), +8 (11%), -7/del7q (8%) and del9q (5%) being the most common ones. The FLT3/ITD mutations (FMS-like tyrosine kinase 3/internal tandem duplication) were observed in 12% of the WHO AML cases, which is much lower than ones in the literature, while the 6% incidence of the FLT3-activating loop mutations (either FLT3/D835 or FLT3/I836) was comparable with others. Both mutations were associated with leukocytosis. Our study also suggests that the FLT3 mutations are biomarkers independent of cytogenetic characteristics.

Adolescent↗
PubMed2004

Cytogenetic abnormalities in products of conception: a relationship revisited.

OBJECTIVES: Cytogenetic evaluation of product of conception (POC) is essential to determine the cause of pregnancy loss and aid the prenatal diagnosis of subsequent pregnancies. The purpose of this study is twofold. (1) To profile cytogenetic abnormalities, their relationship with maternal and gestational age and analyze sex ratios in our case series of 2052 consecutive samples of POC referred to the Baystate Medical Center, Laboratory Genetics between January 1992 and January 1999. (2) To present a comprehensive review of such data published in the last 15 years, in order to study temporal differences in the above parameters and make this information readily available for cytogeneticists and genetic counselors. MATERIALS AND METHODS: Data was entered and analyzed in Epi Info version 6.0 using the Z-test, chi-square test of significance and linear correlation coefficient. RESULTS AND CONCLUSIONS: The profile of cytogenetic abnormalities detected in POC has not changes significantly over time. The mean maternal age in our study (overall and for trisomies) was higher than that reported previously, which is consistent with the noted trend of increasing age at pregnancy in recent years. Our study provides evidence that abnormal karyotypes are aborted earlier and that tetraploidies have the least survival amongst all abnormalities. The higher mean gestational age for trisomic abortions in our study, as compared with previously reported figures, can be attributed to the increasing practice of active maternal screening with subsequent therapeutic abortions. Analysis of sex ratios may reaffirm a female specific developmental disadvantage in early stages of pregnancy.

Adult↗
PubMed1988

Sequential sampling in clinical cytogenetics: a quality control viewpoint.

We have observed that there is some resemblance between the problems of sampling in industrial quality control and the process of diagnosis of mixed cell populations in cytogenetics. This resemblance enabled us to draw from the methodology of the former science to solve some diagnostic problems in the latter. We considered which of the several sampling procedures available for quality control would be more efficient and more suitable in clinical cytogenetics, concluding that 'sequential sampling' combines both features. We also studied the effect that some abnormalities due to technical factors had on sample size required to reach a diagnosis with a given level of confidence. We give a set of tables for sequential sampling in diagnostic laboratories, illustrating their use in discriminating between mosaicism and pseudomosaicism in prenatal diagnosis and in the diagnosis of the fragile X syndrome. Finally, we discuss the merits of sequential sampling as shown here, comparing it with the current method used in cytogenetics to exclude chromosomal mosaicism.

Cytogenetics↗
PubMed2002

Evaluation of paediatric osteosarcomas by classic cytogenetic and CGH analyses.

Classic cytogenetic and comparative genomic hybridisation (CGH) data on osteosarcomas have been reported extensively in the literature. However, the number of paediatric osteosarcoma cases studied below the age of 14 years remains relatively small. This study reports four new cases of paediatric osteosarcoma in patients aged 3 to 13 years, evaluated by classic cytogenetics and CGH analyses. Clonal chromosomal alterations were detected in all the cases and included structural rearrangements at 1p11-13, 1q11, 4q27-33, 6p23-25, 6q16-25, 7p13-22, 7q11-36, 11p10-15, 11q23, 17p11.2-13, 21p11, and 21q11-22. The CGH analysis revealed recurrent gains at 1p, 4q, 17p, and 21q and losses at 3q and 16p. Five amplification sites were observed at 1q11-23, 6p21, 8q13, 8q21.3-24.2, and 17p. The data are discussed and compared with other cytogenetic reports in the literature.

Adolescent↗
PubMed2006

Cytogenetics of Hispanic and White children with acute lymphoblastic leukemia in California.

Epidemiologic studies of childhood leukemia have made limited use of tumor genetic characteristics, which may be related to disease etiology. We characterized the cytogenetics of 543 childhood leukemia patients (0-14 years of age) enrolled in the Northern California Childhood Leukemia Study, an approximately population-based study comprised primarily of Hispanics (42%) and non-Hispanic Whites (41%), and compared the cytogenetic profiles between these two ethnic groups. Subjects were classified by immunophenotype, conventional cytogenetic characteristics, and fluorescence in situ hybridization findings. The ploidy levels most frequently observed among acute lymphoblastic leukemia patients were high hyperdiploidy (51-67 chromosomes) and pseudodiploidy (34% and 27%, respectively). No ethnic differences in the frequency of 11q23/MLL rearrangements were observed between Hispanics and non-Hispanic Whites. Among B-lineage acute lymphoblastic leukemia patients, the percentage of TEL-AML1 translocations was significantly lower in Hispanics (13%) than in non-Hispanic Whites (24%; P = 0.01). This is the first time that this ethnic variation has been observed in a large number of patients in a defined geographic region, which is consistent with findings from smaller international studies. The mechanistic basis for this 2-fold variation in frequency of TEL-AML1 may be due to ethnic-specific risk factors or genetics and should be explored further.

Adolescent↗
PubMed2004

Extended follow-up of patients treated with imatinib mesylate (gleevec) for chronic myelogenous leukemia relapse after allogeneic transplantation: durable cytogenetic remission and conversion to complete donor chimerism without graft-versus-host disease.

PURPOSE: Over the last several years, donor lymphocyte infusions have become the standard approach for patients with chronic myelogenous leukemia (CML) who relapse after allogeneic stem cell transplantation (SCT). Recent reports indicate that imatinib mesylate (Gleevec) can induce remissions in these patients as well. Less is known about the extent and durability of these responses. EXPERIMENTAL DESIGN: We studied 15 patients treated with imatinib for recurrent CML after SCT, 10 patients with stable phase CML (SP-CML), 1 with accelerated phase (AP-CML), and 4 with blast phase (BP-CML). The dose of imatinib was 600 mg (n = 10) or 400 mg (n = 5) daily. Patients were followed for hematological, cytogenetic, and molecular response. A susbset of responders was followed for changes in donor-derived hematopoietic chimerism. RESULTS: Of the 10 patients with SP-CML, all achieved a hematological response. Within 3 months, five of these patients had achieved a complete cytogenetic response (CCR). By six months, 9 of 10 patients had achieved CCR. The BCR-ABL transcript could not be detected by reverse transcription-PCR in 7 of these 9 patients. Patients who achieved CCR showed evidence of conversion to complete donor chimerism. No patient developed graft-versus-host disease. With a median follow up of 25 months, all patients are alive and 9 of 10 patients remain in CCR. Only one of the 5 patients with AP/BP-CML achieved a complete cytogenetic response. CONCLUSIONS: We find that imatinib is well tolerated in patients with SP-CML who relapse after SCT. Responses were rapid, durable, and associated with conversion to full donor chimerism without graft-versus-host disease. Imantinib was far less effective in patients who relapsed with AP/BP-CML. Imatinib should be evaluated as either an alternative or as an adjunct to donor lymphocyte infusions for patients with SP-CML who relapse after SCT.

Adult↗