Spectral Karyotyping: The simultaneous identification of all chromosomes from a cell by fluorescence in situ hybridization (IN SITU HYBRIDIZATION, FLUORESCENCE) with chromosome-specific florescent probes that are discerned by their different emission spectra.Karyotyping: Mapping of the KARYOTYPE of a cell.Chromosome Aberrations: Abnormal number or structure of chromosomes. Chromosome aberrations may result in CHROMOSOME DISORDERS.Chromosome Painting: A technique for visualizing CHROMOSOME ABERRATIONS using fluorescently labeled DNA probes which are hybridized to chromosomal DNA. Multiple fluorochromes may be attached to the probes. Upon hybridization, this produces a multicolored, or painted, effect with a unique color at each site of hybridization. This technique may also be used to identify cross-species homology by labeling probes from one species for hybridization with chromosomes from another species.Chromosome Banding: Staining of bands, or chromosome segments, allowing the precise identification of individual chromosomes or parts of chromosomes. Applications include the determination of chromosome rearrangements in malformation syndromes and cancer, the chemistry of chromosome segments, chromosome changes during evolution, and, in conjunction with cell hybridization studies, chromosome mapping.Neoplasms, Adipose Tissue: Neoplasms composed of fatty tissue or connective tissue made up of fat cells in a meshwork of areolar tissue. The concept does not refer to neoplasms located in adipose tissue.Translocation, Genetic: A type of chromosome aberration characterized by CHROMOSOME BREAKAGE and transfer of the broken-off portion to another location, often to a different chromosome.In Situ Hybridization, Fluorescence: A type of IN SITU HYBRIDIZATION in which target sequences are stained with fluorescent dye so their location and size can be determined using fluorescence microscopy. This staining is sufficiently distinct that the hybridization signal can be seen both in metaphase spreads and in interphase nuclei.Chromosomes, Human, Pair 13: A specific pair of GROUP D CHROMOSOMES of the human chromosome classification.Aneuploidy: The chromosomal constitution of cells which deviate from the normal by the addition or subtraction of CHROMOSOMES, chromosome pairs, or chromosome fragments. In a normally diploid cell (DIPLOIDY) the loss of a chromosome pair is termed nullisomy (symbol: 2N-2), the loss of a single chromosome is MONOSOMY (symbol: 2N-1), the addition of a chromosome pair is tetrasomy (symbol: 2N+2), the addition of a single chromosome is TRISOMY (symbol: 2N+1).Chromosome Breakage: A type of chromosomal aberration involving DNA BREAKS. Chromosome breakage can result in CHROMOSOMAL TRANSLOCATION; CHROMOSOME INVERSION; or SEQUENCE DELETION.Gene Rearrangement: The ordered rearrangement of gene regions by DNA recombination such as that which occurs normally during development.Chromosome Disorders: Clinical conditions caused by an abnormal chromosome constitution in which there is extra or missing chromosome material (either a whole chromosome or a chromosome segment). (from Thompson et al., Genetics in Medicine, 5th ed, p429)Karyotype: The full set of CHROMOSOMES presented as a systematized array of METAPHASE chromosomes from a photomicrograph of a single CELL NUCLEUS arranged in pairs in descending order of size and according to the position of the CENTROMERE. (From Stedman, 25th ed)
Genetic imbalance: Genetic imbalance is to describe situation when the genome of a cell or organism has more copies of some genes than other genes due to chromosomal rearrangements or aneuploidy.Adipose tissue neoplasm: An adipose tissue neoplasm is a neoplasm derived from adipose tissue.Oncogene: An oncogene is a gene that has the potential to cause cancer.Wilbur, Beth, editor.Chromothripsis: Chromothripsis is the phenomenon by which up to thousands of clustered chromosomal rearrangements occur in a single event in localised and confined genomic regions in one or a few chromosomes, and is known to be involved in both cancer and congenital diseases. It occurs through one massive genomic rearrangement during a single catastrophic event in the cell's history.
(1/62) The utility of spectral karyotyping in the cytogenetic analysis of newly diagnosed pediatric acute lymphoblastic leukemia.
We applied multicolor spectral karyotyping (SKY) to a panel of 29 newly diagnosed pediatric pre B-cell ALLs with normal and abnormal G-banded karyotypes to identify cryptic translocations and define complex chromosomal rearrangements. By this method, it was possible to define all add chromosomes in six cases, a cryptic t(12;21)(p13;q11) translocation in six cases, marker chromosomes in two cases and refine the misidentified aberrations by G-banding in two cases. In addition, we identified five novel non-recurrent translocations - t(2;9)(p11.2;p13), t(2;22) (p11.2;q11.2), t(6;8)(p12;p11), t(12;14)(p13;q32) and t(X;8)(p22.3;q?). Of these translocations, t(2;9), t(2;22) and t(12;14) were identified by G-banding analysis and confirmed by SKY. We characterized a t(12;14)( p13;q32) translocation by FISH, and identified a fusion of TEL with IGH for the first time in ALL. We identified a rearrangement of PAX5 locus in a case with t(2;9)(p11.2;p13) by FISH and defined the breakpoint telomeric to PAX5 in der(9)t(3;9)(?;p13). These studies demonstrate the utility of using SKY in combination with G-banding and FISH to augment the precision with which chromosomal aberrations may be identified in tumor cells. (+info)
(2/62) Multicolor karyotyping and clinicopathological analysis of three intravascular lymphoma cases.
Intravascular lymphoma (IVL) is a rare neoplastic disease characterized by the presence of large malignant lymphoid cells in small vessels. It is often diagnosed at autopsy. Clinical manifestations are typically neurologic and dermatologic. Karyotypic abnormalities have been described in a small number of cases and have revealed complex alterations in the majority of cases. We have identified three cases of IVL with varied clinicopathological findings. Karyotypic analysis was undertaken by standard G-banding and supplemented by multi-colored karyotyping (M-FISH) to decipher the chromosomal content of marker chromosomes and undefined additions. M-FISH clarified the chromosomal abnormalities in two cases and unveiled cryptic translocations der(10)t(10;22), der(17)t(17;22), and balanced t(11;14). Comparison with previously published karyotypes revealed prominent involvement of chromosomes 1, 3, 6, 11, 14, and 18, similar to the pattern of clonal evolution in other B-cell lymphomas. The most frequent alterations seen were -6 or 6q- and +18 or dup(18q), with a minimally deleted region located at 6q21-q23 and a commonly amplified region located at 18q13-q23, respectively. Few differences between the classical and Asian variant of this disease were apparent at the karyotypic level. Cytogenetic analysis of additional cases supplemented by multicolor karyotyping may help identify the full spectrum of genetic alterations associated with IVL and assist in the delineation of the critical mutations associated with initiation and progression of this disease. (+info)
(3/62) ALK+, CD30-, CD20- large B-cell lymphoma containing anaplastic lymphoma kinase (ALK) fused to clathrin heavy chain gene (CLTC).
Pathological features and genomic basis of a rare case of ALK(+), CD30(-), CD20(-) large B-cell lymphoma were analyzed. A 36-year-old Japanese female was admitted because of lumbago and constitutional symptoms. Physical examination and laboratory tests showed anemia (hemoglobin, 7.5 g/dL), mild hepatosplenomegaly, and immunoglobin G (IgG) lambda-type monoclonal gammopathy (IgG, 2782 mg/dL). The lymphoma spread exclusively in extranodal sites such as bone marrow, liver, spleen, ovary, and muscle. Biopsy specimens obtained from the ovary showed monomorphic proliferation of large immunoblastic cells with basophilic cytoplasm, round-shaped nuclei with a high nuclear to cytoplasmic ratio, and prominent single nucleolus. Immunostaining with anti-anaplastic lymphoma kinase (ALK) antibody, ALK1, showed finely granular cytoplasmic staining pattern. These cells were also positive for epithelial membrane antigen, CD4, CD19, CD38, CD138, cytoplasmic IgG, and lambda chain, but negative for CD30 (Ber-H2), CD56, CD57, and other T- and B-cell markers. Southern blot analyses revealed that Ig heavy and lambda light chain genes, but not T-cell receptor (TCR) beta gene, were clonally rearranged. Chromosomal analyses by conventional G-banding, spectral karyotyping, and fluorescence in situ hybridization showed complex abnormality involving 2p23, and chromosome 2 was translocated to chromosome 17. As 2;17 translocation resulting in the fusion of clathrin heavy chain (CLTC) gene with ALK was previously reported in inflammatory myofibroblastic tumor, we performed reverse transcriptase-polymerase chain reaction and demonstrated that the lymphoma cells contained CLTC-ALK fusion transcript. Under the diagnosis of ALK(+), CD30(-), CD20(-) large B-cell lymphoma, she was treated with conventional combination chemotherapies. However, the lymphoma was primarily chemotherapy resistant, and the patient died 11 months after admission. We consider that this case confirms the existence of ALK(+), CD30(-), CD20(-) large B-cell lymphomas proposed by Delsol et al. (16) and further provides relevant information regarding their clinicopathological features and cytogenetics. (+info)
(4/62) Karyotypic complexity of the NCI-60 drug-screening panel.
We used spectral karyotyping to provide a detailed analysis of karyotypic aberrations in the diverse group of cancer cell lines established by the National Cancer Institute for the purpose of anticancer drug discovery. Along with the karyotypic description of these cell lines we defined and studied karyotypic complexity and heterogeneity (metaphase-to-metaphase variations) based on three separate components of genomic anatomy: (a) ploidy; (b) numerical changes; and (c) structural rearrangements. A wide variation in these parameters was evident in these cell lines, and different association patterns between them were revealed. Analysis of the breakpoints and other specific features of chromosomal changes across the entire set of cell lines or within particular lineages pointed to a striking lability of centromeric regions that distinguishes the epithelial tumor cell lines. We have also found that balanced translocations are as frequent in absolute number within the cell lines derived from solid as from hematopoietic tumors. Important similarities were noticed between karyotypic changes in cancer cell lines and that seen in primary tumors. This dataset offers insights into the causes and consequences of the destabilizing events and chromosomal instability that may occur during tumor development and progression. It also provides a foundation for investigating associations between structural genome anatomy and cancer molecular markers and targets, gene expression, gene dosage, and resistance or sensitivity to tens of thousands of molecular compounds. (+info)
(5/62) Features of chromosomal abnormalities in spontaneous abortion cell culture failures detected by interphase FISH analysis.
Cytogenetic analysis of reproductive wastage is an important stage in understanding the genetic background of early embryogenesis. The results of conventional cytogenetic studies of spontaneous abortions depend on tissue culturing and are associated with a significant cell culture failure rate. We performed interphase dual-colour FISH analysis to detect chromosomal abnormalities in noncultured cells from two different tissues-cytotrophoblast and extraembryonic mesoderm-of 60 first-trimester spontaneous abortions from which cells had failed to grow in culture. An original algorithm was proposed to optimize the interphase karyotype screening with a panel of centromere-specific DNA probes for all human chromosomes. The overall rate of numerical chromosomal abnormalities in these cells was 53%. Both typical and rare forms of karyotype imbalance were found. The observation of six cases (19%) of monosomy 7, 15, 21 and 22 in mosaic form, with a predominant normal cell line, was the most unexpected finding. Cell lines with monosomies 21 and 22 were found both in cytotrophoblast and mesoderm, while cells with monosomy 7 and 15 were confined to the cytotrophoblast. The tissue-specific compartmentalization of cell lines with autosomal monosomies provides evidence that the aneuploidy of different human chromosomes may arise during different stages of intrauterine development. The effect of aneuploidy on selection may differ, however, depending on the specific chromosome. The abortions also revealed a high frequency of intratissue chromosomal mosaicism (94%), in comparison with that detected by conventional cytogenetic analysis (29%; P<0.001). Confined placental mosaicism was found in 25% of the embryos. The results of molecular cytogenetic analysis of these cell culture failures illustrate that the diversity and phenotypic effects of chromosomal abnormalities during the early stages of human development are underestimated. (+info)
(6/62) A novel FISH assay for SS18-SSX fusion type in synovial sarcoma.
Synovial sarcoma is a morphologically, clinically and genetically distinct entity that accounts for 5-10% of all soft tissue sarcomas. The t(X;18)(p11.2;q11.2) is the cytogenetic hallmark of synovial sarcoma and is present in more than 90% of the cases. It produces three types of fusion gene formed in part by SS18 from chromosome 18 and by SSX1, SSX2 or, rarely, SSX4 from the X chromosome. The SS18-SSX fusions do not seem to occur in other tumor types, and it has been shown that in synovial sarcoma a clear correlation exists between the type of fusion gene and histologic subtype and, more importantly, clinical outcome. Previous analyses regarding the type of fusion genes have been based on PCR amplification of the fusion transcript, requiring access to good-quality RNA. In order to obtain an alternative tool to diagnose and follow this malignancy, we developed a fluorescence in situ hybridization (FISH) assay that could distinguish between the two most common fusion genes, that is, SS18-SSX1 and SS18-SSX2. The specificity of the selected bacterial artificial chromosome clones used in the detection of these fusion genes, as well as the sensitivity of the analysis in metaphase and interphase cells, was examined in a series of 28 synovial sarcoma samples with known fusion gene status. In all samples, the type of fusion was correctly identified by FISH. Thus, the assay described here should be useful for clarifying unresolved chromosome markers and for identifying fusion gene status in samples from which RNA of sufficient quality for PCR could not be extracted. (+info)
(7/62) Combined genetic and transcriptional profiling of acute myeloid leukemia with normal and complex karyotypes.
BACKGROUND AND OBJECTIVES: Acute myeloid leukemia (AML) is a heterogeneous group of diseases. Patients with a normal karyotype constitute the largest single group; multiple chromosome rearrangements involving three or more chromosomes occur in 5 10% of AML patients. The pathophysiologic mechanisms underlying both groups are largely unknown. In the current study, we have systematically combined transcriptional profiles with cytogenetic data from 15 AML patients with either normal or complex karyotypes. DESIGN AND METHODS: The expression profiles were investigated by unsupervised hierarchical clustering, supervised cluster analysis, and comparative genomic microarray analysis. In addition, the samples were analyzed by G-banding and/or spectral karyotyping and comparative genomic hybridization. RESULTS: Our results show that AML with complex karyotypes exhibit a gene expression profile that is specific to this group of patients. The differentially expressed genes included several located on 5q and 7q, as well as genes involved in controlling cell division. We also found that DNA gains and losses caused by multiple chromosome rearrangements result in altered gene expression in a gene-dosage-dependent manner. INTERPRETATION AND CONCLUSIONS: These data provide insight into the mechanisms of multiple chromosome rearrangements and further demonstrate that the expression patterns of AML are strongly linked to the karyotypic status, even for the relatively undefined cytogenetic subgroup AML with complex karyotype. (+info)
(8/62) Genetic and expression profiles of squamous cell carcinoma of the head and neck correlate with cisplatin sensitivity and resistance in cell lines and patients.
PURPOSE: The choice of treatment for squamous cell carcinoma of the head and neck (SCCHN) is still primarily based on the tumor-node-metastasis classification. However, it is reasonable to believe that biological profiles of SCCHN may be independently associated with response to therapy. The aim of the present study was to examine genetic changes and gene expression profiles that might correlate with sensitivity to cisplatin [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay] in 10 SCCHN cell lines. EXPERIMENTAL DESIGN: Five cisplatin-sensitive and five cisplatin-resistant cell lines [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay] were studied by comparative genomic hybridization, spectral karyotyping, and cDNA microarray analysis (21,632 sequence-validated human cDNA; confirmation by reverse transcriptase-PCR for selected genes). For the MET proto-oncogene, which showed low expression in the chemosensitive cell lines, we did immunohistochemical staining on SCCHN of 29 patients who received induction chemotherapy. RESULTS: The five cisplatin-resistant cell lines showed significantly more genetic imbalances (regions of loss and amplification) and chromosomal abnormalities by comparative genomic hybridization and spectral karyotyping, respectively, than did the five cisplatin-sensitive cell lines. Microarray studies identified approximately 60 genes that clearly distinguish between the two groups of cell lines. Some of these genes are known to be involved in tumor progression, metastasis, and drug resistance. We identified low expression of c-met (immunohistochemistry) as a predictive factor for complete response in nondiploid tumors (P = 0.026). CONCLUSIONS: We conclude that cisplatin sensitivity and resistance are related to distinctive differences in the genetic and expression profiles in individual SCCHN tumor cell lines and in SCCHN patients. The genes we have identified may serve as potential targets for novel treatment strategies. (+info)
Download for free our solidary book to support research on VHL disease