Assuntos
Linfoma não Hodgkin/genética , Proteínas Nucleares/genética , Fosfoproteínas/genética , Proteínas Tirosina Quinases/genética , Quinase do Linfoma Anaplásico , Sequência de Bases , Códon , Humanos , Dados de Sequência Molecular , Proteínas Nucleares/química , Nucleofosmina , Fosfoproteínas/química , Proteínas Tirosina Quinases/química , Receptores Proteína Tirosina Quinases , Translocação Genética , Células Tumorais CultivadasRESUMO
The 2;5 chromosomal translocation occurs in most anaplastic large-cell non-Hodgkin's lymphomas arising from activated T lymphocytes. This rearrangement was shown to fuse the NPM nucleolar phosphoprotein gene on chromosome 5q35 to a previously unidentified protein tyrosine kinase gene, ALK, on chromosome 2p23. In the predicted hybrid protein, the amino terminus of nucleophosmin (NPM) is linked to the catalytic domain of anaplastic lymphoma kinase (ALK). Expressed in the small intestine, testis, and brain but not in normal lymphoid cells, ALK shows greatest sequence similarity to the insulin receptor subfamily of kinases. Unscheduled expression of the truncated ALK may contribute to malignant transformation in these lymphomas.
Assuntos
Linfoma Anaplásico de Células Grandes/genética , Proteínas Nucleares/genética , Fosfoproteínas/genética , Proteínas Tirosina Quinases/genética , Translocação Genética , Sequência de Aminoácidos , Quinase do Linfoma Anaplásico , Sequência de Bases , Encéfalo/enzimologia , Transformação Celular Neoplásica , Passeio de Cromossomo , Cromossomos Humanos Par 2 , Cromossomos Humanos Par 5 , Clonagem Molecular , Regulação Neoplásica da Expressão Gênica , Humanos , Intestino Delgado/enzimologia , Linfoma Anaplásico de Células Grandes/química , Linfoma Anaplásico de Células Grandes/enzimologia , Masculino , Dados de Sequência Molecular , Proteínas Nucleares/química , Nucleofosmina , Fosfoproteínas/química , Regiões Promotoras Genéticas , Proteínas Tirosina Quinases/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Proteína Tirosina Quinases , Alinhamento de Sequência , Transdução de Sinais , Testículo/enzimologia , Células Tumorais CultivadasAssuntos
Aberrações Cromossômicas , Hibridização In Situ/métodos , Leucemia/genética , Linfoma/genética , Autorradiografia , Southern Blotting/métodos , Sondas de DNA , Enzimas de Restrição do DNA , DNA de Neoplasias/genética , DNA de Neoplasias/isolamento & purificação , Eletroforese em Gel de Ágar , HumanosRESUMO
The q23-q33 region of human chromosome 5 encodes a large number of growth factors, growth factor receptors, and hormone/neurotransmitter receptors. This is also the general region into which several disease genes have been mapped, including diastrophic dysplasia, Treacher Collins syndrome, hereditary startle disease, the myeloid disorders that are associated with the 5q-syndrome, autosomal-dominant forms of hereditary deafness, and limb girdle muscular dystrophy. We have developed a framework physical map of this region using cosmid clones isolated from the Los Alamos arrayed chromosome 5-specific library. Entry points into this library included 14 probes to genes within this interval and one anonymous polymorphic marker locus. A physical map has been constructed using fluorescence in situ hybridization of these cosmids on metaphase and interphase chromosomes, and this is in good agreement with the radiation hybrid map of the region. The derived order of loci across the region is cen-IL4-IL5-IRF1-IL3-IL9-EGR1-CD1 4-FGFA-GRL-D5S207-ADRB2-SPARC-RPS14+ ++-CSF1R- ADRA1, and the total distance spanned by these loci is approximately 15 Mb. The framework map, genomic clones, and contig expansion within 5q23-q33 should provide valuable resources for the eventual isolation of the clinically relevant loci that reside in this region.
Assuntos
Mapeamento Cromossômico , Cromossomos Humanos Par 5 , Clonagem Molecular , Cosmídeos , Humanos , Hibridização in Situ Fluorescente , Masculino , Células Tumorais CultivadasRESUMO
A method is described for the isolation of chromosome region specific cosmids. The 5q35 region of the long arm of human chromosome 5 was microdissected, digested with MboI, ligated to oligonucleotide adaptors, amplified by the polymerase chain reaction and cloned into a plasmid vector. Inserts which did not contain highly repetitive sequences were used to screen a chromosome 5 cosmid library by direct hybridization. There were 33 positive cosmid clones identified with 4 microclones. Individual cosmid clones were biotinylated and used as probes for fluorescence in situ hybridization to metaphase chromosomes. Of the 33 cosmids that were mapped, 29 localized to q35 and 4 to q34, demonstrating the specificity of the microdissection library and the cosmids.
Assuntos
Cromossomos Humanos Par 5 , Cosmídeos , Sequência de Bases , Southern Blotting , Clonagem Molecular , DNA , Biblioteca Gênica , Humanos , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Reação em Cadeia da PolimeraseRESUMO
Macrophage colony stimulating factor (CSF-1) is a member of a family of glycoproteins that are necessary for the normal proliferation and differentiation of myeloid progenitor cells. The human CSF-1 gene has previously been assigned to chromosome 5 using somatic cell hybrids, and further localized to 5q33 by in situ hybridization with a 3H labelled cDNA probe. However, the murine macrophage colony stimulating factor gene (csfm) has been localized to a region on mouse chromosome 3 which was previously shown to be syntenic with the proximal region of 1p and not 5q. Using a human genomic DNA clone that contains the CSF-1 gene, we have localized CSF-1 to chromosome 1p13-21 by fluorescence in situ hybridization. The reassignment of the CSF-1 gene argues against its involvement in myeloid disorders with deletions of the long arm of chromosome 5.
Assuntos
Artefatos , Cromossomos Humanos Par 1 , Fator Estimulador de Colônias de Macrófagos/genética , Animais , Sequência de Bases , Linhagem Celular , Mapeamento Cromossômico , Cromossomos Humanos Par 5 , Clonagem Molecular , DNA/genética , DNA/isolamento & purificação , Humanos , Cariotipagem , Metáfase , Camundongos , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos , Reação em Cadeia da Polimerase/métodos , Espectrometria de FluorescênciaRESUMO
The protooncogene c-kit is critical for development of hematopoietic stem cells, germ cells, and melanoblasts in the mouse. Homozygous mutations of this gene in the mouse cause anemia, infertility, and albinism, whereas heterozygous mutant mice usually exhibit only a white forehead blaze and depigmentation of the ventral body, tail, and feet. The heterozygous mouse phenotype is very similar to human piebald trait, which is characterized by a congenital white hair forelock and ventral and extremity depigmentation. To investigate the possibility that alterations in the human c-kit gene may be a cause of piebald trait, DNA from seven unrelated affected individuals was examined by Southern blot analysis. One subject, although cytogenetically normal, has a heterozygous deletion of the c-kit protooncogene. This deletion encompasses the entire coding region for c-kit and also involves the closely linked gene for platelet-derived growth factor receptor alpha. Fluorescence in situ hybridization of genomic c-kit probes to metaphase chromosomes independently confirmed the deletion in this case. These findings provide molecular evidence mapping piebald trait to the c-kit locus on chromosome 4. Although we cannot exclude the involvement of other closely linked genes, the demonstration of a genomic c-kit deletion in one subject with piebald trait and the marked concordance of the human and mouse phenotypes provide strong evidence for the role of c-kit in the development of human melanocytes and in the pathogenesis of piebald trait.
Assuntos
Quimiocinas CXC , Deleção Cromossômica , Cromossomos Humanos Par 4 , Peptídeos e Proteínas de Sinalização Intercelular , Piebaldismo/genética , Proteínas Proto-Oncogênicas/genética , Proto-Oncogenes , Animais , Southern Blotting , Quimiocina CXCL1 , DNA/genética , DNA/isolamento & purificação , Feminino , Triagem de Portadores Genéticos , Genótipo , Substâncias de Crescimento/genética , Humanos , Interleucina-2/genética , Masculino , Camundongos , Camundongos Endogâmicos C3H , Proteínas de Neoplasias/genética , Hibridização de Ácido Nucleico , Fator de Crescimento Derivado de Plaquetas/metabolismo , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas c-kit , Receptores de Superfície Celular/genética , Receptores do Fator de Crescimento Derivado de Plaquetas , Mapeamento por RestriçãoRESUMO
We have characterized a chromosomal translocation in a cell line (SU-DUL5) established from a patient with lymphoblastic lymphoma in which the c-myc gene on chromosome 8 was juxtaposed to a t(14;18). Cytogenetic analysis of this cell line showed 14q+, 18q-, and 8p+q+ marker chromosomes in the absence of t(14;18). Genomic Southern blot analysis showed juxtaposition of the immunoglobulin heavy chain joining region (JH) with chromosome 18 near the minor breakpoint cluster region (mcr) of the bcl-2 gene. There was also a rearranged c-myc gene detectable with a 5' c-myc probe. Molecular cloning studies showed that the c-myc gene was joined to chromosome 18 DNA. Nucleotide sequence analysis of cloned breakpoint DNA revealed that the crossover between chromosomes 8 and 18 occurred at the 3' end of the bcl-2 gene resulting in replacement of the bcl-2 gene on the 14q+ chromosome with the c-myc gene. As a result of this translocation the SU-DUL5 cell line contains no detectable bcl-2 mRNA or protein but has abundant levels of c-myc mRNA. Our data suggest that bcl-2 inactivation occurred simultaneously with c-myc translocation in a B cell lymphoblastic lymphoma.
Assuntos
Regulação Neoplásica da Expressão Gênica , Genes myc/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Proteínas Proto-Oncogênicas/genética , Proto-Oncogenes/genética , Translocação Genética/genética , Adulto , Sequência de Bases , Northern Blotting , Linhagem Celular , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 18 , Cromossomos Humanos Par 8 , Humanos , Cariotipagem , Masculino , Dados de Sequência Molecular , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2 , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
Non-random translocation involving the short arm of chromosome 19 are frequently observed in acute leukemias. Recent studies have shown that the 19p13 genes E2A and LYLl, both of which encode helix-loop-helix proteins, lie at two different translocation breakpoints in acute lymphoblastic leukemias (ALL). The E2A gene is involved by the t(1;19)(q23;p13) in acute pre-B-cell leukemias and the LYL1 gene is structurally altered by a t(7;19)(q34;p13) in T-cell ALL. To assess the role of these genes in other leukemia-associated translocations we mapped their locations with respect to the t(11;19)(q23;p13) and t(4;19)(q21;p13) translocation breakpoints carried by T-ALL cell lines SUP-T13 and SUP-T8a, respectively. In situ hybridization studies indicated that the E2A and LYL1 genes are physically distinct from the t(4;19) and t(11;19) breakpoints. Using these and other 19p13 translocation breakpoints as landmarks, we established a partial physical map of 19p: 19pter-E2A-INSR-LYL1-[t(4;19)]-19cen. These data should help guide molecular studies to further characterize 19p13 breakpoints and mapping of genes in this chromosomal region.
Assuntos
Cromossomos Humanos Par 19 , Leucemia de Células T/genética , Translocação Genética , Doença Aguda , Mapeamento Cromossômico , Sondas de DNA , Proteínas de Ligação a DNA/genética , Humanos , Cariotipagem , Hibridização de Ácido Nucleico , Receptor de Insulina/genética , Células Tumorais CultivadasRESUMO
To establish the clonal origin of a case of concomitant B-cell chronic lymphocytic leukemia (IgM kappa) and multiple myeloma (IGA lambda), we analyzed the immunoglobulin (Ig) gene rearrangements in the patient's blood and bone marrow. Despite the different isotypes, pretreatment investigation of the heavy chain gene (JH) revealed a germline fragment and two identical rearrangements in the blood and marrow. Both kappa and lambda light-chain genes were rearranged in the blood, suggesting peripheral blood lymphocyte involvement in the myeloma. Analysis of the Ig genes after chemotherapy demonstrated no change in the JH or CK rearrangements; however, the lambda genes were now in a germline configuration. Our results suggest that in this patient both chronic lymphocytic leukemia and myeloma originated from the same B-cell progenitor.
Assuntos
Rearranjo Gênico de Cadeia Pesada de Linfócito B , Genes de Imunoglobulinas , Leucemia Linfocítica Crônica de Células B/patologia , Mieloma Múltiplo/patologia , Antígenos de Neoplasias/análise , Antígenos de Superfície/análise , Southern Blotting , Células Clonais , Humanos , Leucemia Linfocítica Crônica de Células B/complicações , Leucócitos Mononucleares/imunologia , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/complicaçõesRESUMO
A new cell line, NCEB-1, was established by Epstein-Barr virus (EBV) transformation of peripheral blood mononuclear cells from a patient with centroblastic-centrocytic diffuse lymphoma expressing IgM lambda. The transformed cells were lymphoblastoid, with many cells showing a plasmacytoid morphology. The NCEB-1 cells had cytoplasmic Ig (CyIg), with loss of the surface Ig (SIg) expression. Cytogenetic analysis of the cell line demonstrated two clones with variations: a hypodiploid clone, with a complex karyotype including a t(11;14)(q13;q32) similar to the original tumor cells, and a near tetraploid clone with the same markers. Southern blot analysis of DNA from the patient's neoplastic cells and NCEB-1 demonstrated identical Ig heavy chain gene rearrangement, confirming the origin of the cell line. The cell line was not tumorigenic when tested in an in vitro assay using immunosuppressed mice. NCEB-1 has been in continuous culture for 9 months and will be valuable for the in vivo study of non-Hodgkin's lymphoma and EBV transformation.
