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1.
Qual Life Res ; 25(5): 1257-63, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26471263

RESUMO

PURPOSE: The purpose of this study was to conduct a longitudinal examination of cognitive complaints and functional status in patients with chronic fatigue syndrome (CFS) alone and those who also had fibromyalgia (CFS/FM). METHODS: A total of 93 patients from a tertiary care fatigue clinic were evaluated on four occasions, each 6 months apart. Each evaluation included a tender point assessment, and self-reported functional status and cognitive complaints. RESULTS: Patients with CFS/FM reported significantly worse physical functioning, more bodily pain, and more cognitive difficulties (visuo-perceptual ability and verbal memory) than patients with CFS alone. Over time, bodily pain decreased only for participants with CFS alone. Verbal memory problems were associated with more bodily pain for both patient groups, whereas visuo-perceptual problems were associated with worse functional status for patients with CFS alone. CONCLUSIONS: This study adds to the literature on functional status, longitudinal course, and cognitive difficulties among patients with CFS and those with CFS and FM. The results suggest that patients with CFS/FM are more disabled, have more cognitive complaints, and improve more slowly over time than patients with CFS alone. Specific cognitive difficulties are related to worse functional status, which supports the addition of cognitive difficulties to the FM case criteria.


Assuntos
Cognição , Síndrome de Fadiga Crônica/psicologia , Fibromialgia/psicologia , Transtornos da Memória/complicações , Qualidade de Vida/psicologia , Adolescente , Adulto , Idoso , Pessoas com Deficiência/psicologia , Fadiga/complicações , Síndrome de Fadiga Crônica/diagnóstico , Feminino , Fibromialgia/diagnóstico , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
2.
Br J Cancer ; 107(8): 1423-32, 2012 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-22955849

RESUMO

BACKGROUND: Prolyl hydroxylation is a post-translational modification that affects the structure, stability and function of proteins including collagen by catalysing hydroxylation of proline to hydroxyproline through action of collagen prolyl hydroxylases3 (C-P3H) and 4 (C-P4H). Three C-P3Hs (nomenclature was amended according to approval by the HGNC symbols and names at http://www.genenames.org/ and Entrez database at http://www.ncbi.nlm.nih.gov/gene) leucineproline-enriched proteoglycan (leprecan) 1 (Lepre1), leprecan-like 1 (Leprel1), leprecan-like 2 (Leprel2) and two paralogs Cartilage-Related Protein (CRTAP) and leprecan-like 4 (Leprel4) are found in humans. The C-P4Hs are tetrameric proteins comprising a variable α subunit, encoded by the P4HA1, P4HA2 and P4HA3 genes and a constant ß subunit encoded by P4HB. METHODS: We used RT-PCR, qPCR, pyrosequencing, methylation-specific PCR, western blotting and immunohistochemistry to investigate expression and regulation of the C-P3H and C-P4H genes in B lymphomas and normal bone marrow. RESULTS: C-P3H and C-P4H are downregulated in lymphoma. Down-regulation is associated with methylation in the CpG islands and is detected in almost all common types of B-cell lymphoma, but the CpG islands are unmethylated or methylated at lower levels in DNA isolated from normal bone marrow and lymphoblastoid cell lines. Methylation of multiple C-P3H and C-P4H genes is present in some lymphomas, particularly Burkitt's lymphoma. CONCLUSIONS: Methylation of C-P3H and C-P4H is common in B lymphomas and may have utility in differentiating disease subtypes.


Assuntos
Colágeno/genética , Linfoma de Células B/genética , Pró-Colágeno-Prolina Dioxigenase/genética , Linhagem Celular Tumoral , Colágeno/metabolismo , Ilhas de CpG/genética , Regulação da Expressão Gênica , Inativação Gênica , Humanos , Linfoma de Células B/metabolismo , Metilação , Pró-Colágeno-Prolina Dioxigenase/metabolismo
5.
Blood ; 98(9): 2837-44, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11675358

RESUMO

Chromosomal translocation t(6;14)(p21.1;q32.3) has been reported as a rare but recurrent event not only in myeloma and plasma cell leukemia but also in diffuse large B-cell non-Hodgkin lymphoma (B-NHL) (diffuse large B-cell lymphoma [DLBCL]) and splenic lymphoma with villous lymphocytes (SLVL); however, the nature of the target gene(s) has not been determined. This study identified t(6;14)(p21.1;q32.3) in 3 cases of transformed extranodal marginal zone B-NHL, in 1 case of SLVL, and in 1 case of a low-grade B-cell lymphoproliferative disorder. In a sixth case, a CD5(+) DLBCL, the translocation was identified by molecular cloning in the absence of cytogenetically detectable change. Two chromosomal translocation breakpoints were cloned by using long-distance inverse polymerase chain reaction methods. Comparison with the genomic sequence for chromosome 6p21.1 showed breakpoints approximately 59 and 73.5 kilobases 5' of the cyclin D3 (CCND3) gene with no other identifiable transcribed sequences in the intervening region. Although Southern blotting with derived genomic 6p21.1 probes failed to detect other rearrangements, fluorescent in situ hybridization assays, using BAC (bacterial artificial chromosome) clones spanning and flanking the CCND3 locus, along with probes for IGH confirmed localization of 6p21.1 breakpoints within the same region, as well as fusion of the CCND3 and IGH loci. Furthermore, in all cases, high-level expression of CCND3 was demonstrated at RNA and/or protein levels by Northern and Western blotting and by immunohistochemistry. These data implicate CCND3 as a dominant oncogene in the pathogenesis and transformation in several histologic subtypes of mature B-cell malignancies with t(6;14)(p21.1;q32.3) and suggest that CCND3 overexpression seen in about 10% of DLBCL cases may have a genetic basis.


Assuntos
Cromossomos Humanos Par 14 , Cromossomos Humanos Par 6 , Ciclinas/genética , Linfoma de Células B/genética , Transtornos Linfoproliferativos/genética , Translocação Genética/genética , Adulto , Idoso , Linfócitos B/química , Linfócitos B/patologia , Linfócitos B/ultraestrutura , Sequência de Bases , Quebra Cromossômica/genética , Clonagem Molecular , Ciclina D3 , Feminino , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Linfoma de Células B/química , Linfoma de Células B/patologia , Transtornos Linfoproliferativos/patologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular
6.
Crit Rev Eukaryot Gene Expr ; 11(4): 269-77, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-12067067

RESUMO

Proteolytic modification of certain key regulatory molecules involved in apoptotic and prosurvival pathways may be a feature of the control of programmed cell death. Four molecules of the Bd-2 family (BID, Bcl-2, Bax, Bcl-X(L)) have been reported to be deaved during apoptosis, as has a cellular inhibitor of apoptosis (XIAP). Two proteins involved in NF-kappaB activation, RIP and TRAF1, are cleaved during apoptosis induced by agents that activate both pathways. MEKK1, a molecule involved in a protein kinase stress signaling cascade that contributes to apoptosis and NF-kappaB activation, also undergoes cleavage. In each case, the cleavage products may result in the inactivation of a former function or the gaining of a new function, thus contributing to the delicately balanced regulation of apoptosis.


Assuntos
Apoptose/fisiologia , Sobrevivência Celular/fisiologia , Peptídeos/metabolismo , Transdução de Sinais , Animais , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3 , Proteínas de Transporte/fisiologia , Caspase 3 , Caspases/fisiologia , Morte Celular/fisiologia , Genes bcl-2/genética , Humanos , Hidrólise , Proteínas/metabolismo , Proteínas Proto-Oncogênicas/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Ratos , Proteína Serina-Treonina Quinases de Interação com Receptores , Fator 1 Associado a Receptor de TNF , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X , Proteína X Associada a bcl-2 , Proteína bcl-X
7.
Am J Pathol ; 157(4): 1147-54, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11021819

RESUMO

BCL10 is an apoptotic regulatory molecule identified through its direct involvement in t(1;14)(p22;q32) of mucosa-associated lymphoid tissue (MALT) lymphoma. We examined BCL10 protein expression in various normal tissues and B-cell lymphomas by immunohistochemistry of formalin-fixed and paraffin-embedded tissues using mouse BCL10 monoclonal antibodies. BCL10 protein was expressed in lymphoid tissue but not in 21 various other tissues with the exception of breast. In normal B-cell follicles, the protein was expressed abundantly in the germinal center B cells, moderately in the marginal zone, but only weakly in the mantle zone B cells. Irrespective of their stage of B-cell maturation, BCL10 was predominantly expressed in the cytoplasm. In contrast, each of the four MALT lymphomas with t(1;14)(p22;q32) showed strong BCL10 expression in both the nucleus and cytoplasm. Twenty of 36 (55%) MALT lymphomas lacking the translocation exhibited BCL10 expression in both the nucleus and cytoplasm although at a much lower level, whereas the remaining 16 cases displayed only cytoplasmic BCL10. Unlike MALT lymphoma, both follicular and mantle cell lymphomas generally displayed BCL10 expression compatible to their normal cell counterparts. Our results show differential expression of BCL10 protein among various B-cell populations of the B-cell follicle, indicating its importance in B-cell maturation. The subcellular localization of BCL10 was frequently altered in MALT lymphoma in comparison with its normal cell counterparts, suggesting that ectopic BCL10 expression may be important in the development of this type of tumor.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Núcleo Celular/metabolismo , Tecido Linfoide/metabolismo , Linfoma de Zona Marginal Tipo Células B/metabolismo , Linfoma de Células B/metabolismo , Proteínas de Neoplasias/metabolismo , Proteína 10 de Linfoma CCL de Células B , Western Blotting , Feto , Humanos , Imuno-Histoquímica , Valores de Referência , Frações Subcelulares/metabolismo , Distribuição Tecidual
8.
J Virol ; 74(7): 3082-92, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10708423

RESUMO

CST (BART BARF0) family viral RNAs are expressed in several types of Epstein-Barr virus (EBV) infection, including EBV-associated cancers. Many different spliced forms of these RNAs have been described; here we have clarified the structures of some of the more abundant splicing patterns. We report the first cDNAs representing a full-length CST mRNA from a clone library and further characterize the transcription start. The relative abundance of splicing patterns and genomic analysis of the open reading frames (ORFs) suggest that, in addition to the much studied BARF0 ORF, there may be important products made from some of the upstream ORFs in the CST RNAs. Potential biological functions are identified for two of these. The product of the RPMS1 ORF is shown to be a nuclear protein that can bind to the CBF1 component of Notch signal transduction. RPMS1 can inhibit the transcription activation induced through CBF1 by NotchIC or EBNA-2. The protein product of another CST ORF, A73, is shown to be a cytoplasmic protein which can interact with the cell RACK1 protein. Since RACK1 modulates signaling from protein kinase C and Src tyrosine kinases, the results suggest a possible role for CST products in growth control, perhaps consistent with the abundant transcription of CST RNAs in cancers such as nasopharyngeal carcinoma.


Assuntos
Herpesvirus Humano 4/genética , RNA Viral/genética , Proteínas Virais/genética , Sequência de Aminoácidos , Sequência de Bases , Primers do DNA , DNA Complementar , Genoma Viral , Células HeLa , Humanos , Dados de Sequência Molecular , Fases de Leitura Aberta , Regiões Promotoras Genéticas , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico
9.
J Virol ; 74(6): 2793-803, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10684296

RESUMO

The transcription of two early "leftwardly" expressed genes carrying repetitive sequences, IR2 and IR4, has been studied for Epstein-Barr virus-associated tumors, and for established B-cell lines, using sequence-specific probes generated for this purpose. Whereas the IR4 transcript was identified in every tumor and cell line assessed (except B95-8, with a deletion that removes the gene), expression of the IR2 gene was restricted to B lymphocytes. Though the promoters for both transcripts lie within homologous regions (D(L) and D(R)) in the viral genome, the IR2 promoter appears more tightly regulated. Detailed characterization of the IR4 transcript from a nasopharyngeal carcinoma tumor, C15, identifies a sequence variant of this gene that differs from those reported for B cells; in situ hybridization methods show transcription to be restricted to a subset of cells, with the strongest signals seen adjacent to host stroma. As with B cells in culture (Y. Gao, P. R. Smith, L. Karran, Q. L. Lu, and B. E. Griffin, J. Virol. 71:84-94, 1997), chemical induction enhanced transcriptional expression of the IR4 gene in the C15 tumor, although staining for both the IR4 antigen and that of the virus lytic switch, Zta, gave negative results. In a Burkitt's lymphoma biopsy specimen, however, both proteins were found expressed, notably in the same subset of cells. The data here and elsewhere (Gao et al., J. Virol., 1997) are consistent with a block to intracellular transport of the transcript(s) and suggest nuclear roles for it in tumors, possibly in RNA processing and viral lytic replication. Both roles could be fulfilled in the absence of translation.


Assuntos
Linfoma de Burkitt/virologia , Regulação Viral da Expressão Gênica , Genes Precoces , Herpesvirus Humano 4/genética , Proteínas Imediatamente Precoces/genética , Neoplasias Nasofaríngeas/virologia , Proteínas Virais/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Linfoma de Burkitt/patologia , Callithrix , Linhagem Celular , Clonagem Molecular , Sondas de DNA , DNA Complementar , DNA Viral , Humanos , Proteínas Imediatamente Precoces/fisiologia , Camundongos , Camundongos Nus , Dados de Sequência Molecular , Neoplasias Nasofaríngeas/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica , Células Tumorais Cultivadas , Proteínas Virais/fisiologia , Proteínas Virais Reguladoras e Acessórias
10.
Cell ; 96(1): 35-45, 1999 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-9989495

RESUMO

MALT B cell lymphomas with t(1;14)(p22;q32) showed a recurrent breakpoint upstream of the promoter of a novel gene, Bcl10. Bcl10 is a cellular homolog of the equine herpesvirus-2 E10 gene: both contain an amino-terminal caspase recruitment domain (CARD) homologous to that found in several apoptotic molecules. Bcl10 and E10 activated NF-kappaB but caused apoptosis of 293 cells. Bcl10 expressed in a MALT lymphoma exhibited a frameshift mutation resulting in truncation distal to the CARD. Truncated Bcl10 activated NF-kappaB but did not induce apoptosis. Wild-type Bcl10 suppressed transformation, whereas mutant forms had lost this activity and displayed gain-of-function transforming activity. Similar mutations were detected in other tumor types, indicating that Bcl10 may be commonly involved in the pathogenesis of human malignancy.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 1 , Linfoma de Zona Marginal Tipo Células B/genética , Mutação , Proteínas de Neoplasias/genética , Translocação Genética , Sequência de Aminoácidos , Animais , Apoptose , Proteína 10 de Linfoma CCL de Células B , Sequência de Bases , Células COS , Linhagem Celular Transformada , Transformação Celular Neoplásica , Clonagem Molecular , Expressão Gênica , Células HeLa , Humanos , Camundongos , Dados de Sequência Molecular , NF-kappa B/metabolismo , Proteínas de Neoplasias/fisiologia , Neoplasias/genética , Homologia de Sequência de Aminoácidos
11.
J Virol ; 71(1): 84-94, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8985326

RESUMO

An Epstein-Barr virus transcript (designated D-HIT [Daudi high-level-inducible transcript]), constitutively expressed at low levels in the Burkitt's lymphoma (BL)-derived cell line Daudi, can be induced with tetradecanoylphorbol acetate or n-butyrate or, in combination, to about 1% of the levels of high-molecular-weight RNAs in cells. The transcript can also be induced in some other EBV-positive BL-derived cells but to a much lesser extent, particularly in lines that can give rise to productive infection. D-HIT is viral in origin and is composed largely of repetitive sequence. It is polyadenylated but mainly nuclear in location and is highly structured, sensitive only to double-strand-specific RNase. It is endogenously expressed in interferon-sensitive Daudi strains but not in an insensitive strain, Daudi 100K. D-HIT contains a part of a viral open reading frame (designated LF3, and deleted in the prototype B95-8 strain), using an internal polyadenylation (AAUAAA) sequence as a signal to specify processing of its 3' end. In Daudi cells, the promoter contains a putative hinge structure, as found in some interferon-inducible genes and c-myc. Since D-HIT lies adjacent to, probably even encompassing, one of the two viral lytic origins (D(R)) of replication, it may have a role in the regulation of DNA replication. Alternatively, or in addition via its double-stranded structure, D-HIT may play a regulatory role in interferon pathways. Its promoter could be of value for studying expression in constructions containing heterologous genes.


Assuntos
Linfoma de Burkitt/virologia , Herpesvirus Humano 4/genética , RNA Viral , Sequência de Bases , Linfoma de Burkitt/patologia , DNA Viral , Genoma Viral , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Biossíntese de Proteínas , RNA de Cadeia Dupla , Células Tumorais Cultivadas
12.
J Gen Virol ; 77 ( Pt 6): 1173-80, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8683204

RESUMO

Epstein-Barr virus (EBV) infection of the common marmoset causes long-term infection, with production of antibodies to virus-induced antigens, without clinical illness. Attempts to show the presence of EBV DNA in saliva of infected animals by PCR were initially unsuccessful, although slot-blot hybridization analysis demonstrated that viral DNA was present. Further investigations showed that most samples of pilocarpine-induced saliva, and 33% of the samples of whole mouth fluids (WMF) tested, were inhibitory to PCR. Similar results were found using human WMF. A method of assessing samples of marmoset WMF for the presence of EBV, by PCR using an EBV BamHI W probe, and removing inhibition with Chelex 100, is described. A total of 202 samples from 21 EBV infected, and seven non-infected animals was tested. Five seropositive animals shed virus on every occasion, and 15 intermittently. Two marmosets, infected as neonates, showed progressively increasing humoral responses to viral antigens, and shed virus on every occasion tested over 3 years. When mated with uninfected animals, the latter seroconverted 4 and 6 weeks later, respectively, and later shed virus into their WMF. The naturally infected animals were paired with naive marmosets, and were able to pass on infection. These results establish that long-term, permissive EBV infection occurs in the common marmoset, and demonstrate again the similarities in the response to EBV between marmoset and man.


Assuntos
Callithrix/virologia , Infecções por Herpesviridae/veterinária , Herpesvirus Humano 4 , Reação em Cadeia da Polimerase/métodos , Doenças dos Primatas , Infecções Tumorais por Vírus/veterinária , Animais , Anticorpos Antivirais/sangue , Sequência de Bases , Cromossomos , Primers do DNA , DNA Viral/análise , Infecções por Herpesviridae/diagnóstico , Herpesvirus Humano 4/imunologia , Herpesvirus Humano 4/isolamento & purificação , Humanos , Dados de Sequência Molecular , Boca/virologia , Valores de Referência , Saliva/virologia , Infecções Tumorais por Vírus/diagnóstico
13.
Int J Cancer ; 60(4): 562-6, 1995 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-7829271

RESUMO

Random sequencing of clones from a lambda gt10 cDNA library, made from mRNA expressed in an Epstein-Barr virus (EBV)-associated nasopharyngeal carcinoma (NPC) has revealed the gene transcript of human CD24. The CD24 antigen, a glycosylphosphatidylinositol-anchored cell surface molecule, has been identified as a B-cell marker that is lost during cell maturation. We show here that it is expressed on 3 NPC xenografts, previously defined as consisting of poorly differentiated epithelial cells, and on an NPC biopsy. In the case of the former, the level of expression of CD24 corresponds to the EBV load. A B-lymphoblastoid cell line carrying the same EBV genome as one of the tumours, C15, and an EBV-negative Burkitt's lymphoma cell line do not display the antigen, but epithelial-like cells of a laryngeal tumour cell line (Hep2) do express it. Our data suggest that CD24 may be a marker of cell differentiation not only for B cells but also for epithelial cells and may have an indirect association with EBV gene expression.


Assuntos
Antígenos CD/biossíntese , Antígenos de Neoplasias/biossíntese , Herpesvirus Humano 4/imunologia , Glicoproteínas de Membrana , Neoplasias Nasofaríngeas/imunologia , Neoplasias Nasofaríngeas/virologia , Animais , Antígenos CD/genética , Antígenos de Neoplasias/genética , Linfócitos B/imunologia , Linfócitos B/metabolismo , Sequência de Bases , Northern Blotting , Antígeno CD24 , Diferenciação Celular , Primers do DNA , DNA de Neoplasias/genética , Regulação Neoplásica da Expressão Gênica , Regulação Viral da Expressão Gênica , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Nus , Dados de Sequência Molecular , RNA Mensageiro/análise , RNA Neoplásico/análise , Células Tumorais Cultivadas/imunologia
14.
J Virol ; 67(6): 3217-25, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8098777

RESUMO

The most abundant polyadenylated viral transcripts in the Epstein-Barr virus (EBV)-associated tumor nasopharyngeal carcinoma are a family (apparent sizes, 4.8, 5.2, 6.2, and 7.0 kb) of highly spliced cytoplasmic RNAs expressed from the BamHI-I and -A regions of the viral genome in an antisense direction with respect to several viral lytic functions encoded within the same region and concerned with the lytic cycle of the virus. We have called these complementary-strand transcripts. They are also expressed in B cells, including Burkitt's lymphoma and EBV-immortalized marmoset cell lines, and tumors generated in cottontop tamarins in response to EBV infection, but at a lower level. The complete structure of the major 4.8-kb RNAs (seven or eight exons) was determined in this study; the larger, but related, transcripts appear to be produced by differential splicing. The transcriptional promoter for the major complementary-strand transcripts, located in BamHI-I, contains several well-characterized transcriptional control elements (E2A, SP1, and AP1) and is functionally active in both B lymphocytes and epithelial cells. It appears to be a bifunctional viral promoter, as it also contains the initiation codon for a gene (BILF2) that encodes a glycoprotein that is expressed off the other strand. Splicing events create a number of small AUG-initiated open reading frames, one of which has homology to functionally significant regions of the EBV-encoded nuclear antigen 2 and to E2 (in papillomavirus). The complex nature of these transcripts and their potential role in the virus association with malignancy are considered.


Assuntos
Herpesvirus Humano 4/genética , Neoplasias Nasofaríngeas/genética , Poli A/genética , RNA Mensageiro/genética , Sequência de Aminoácidos , Animais , Antígenos Virais/genética , Linfócitos B/microbiologia , Sequência de Bases , Códon , Proteínas de Ligação a DNA/genética , Antígenos Nucleares do Vírus Epstein-Barr , Éxons/genética , Humanos , Camundongos , Camundongos Nus , Dados de Sequência Molecular , Fases de Leitura Aberta , Terminação Traducional da Cadeia Peptídica/genética , Regiões Promotoras Genéticas/genética , Splicing de RNA , RNA Viral/genética , Integração Viral/genética
15.
Proc Natl Acad Sci U S A ; 89(17): 8058-62, 1992 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-1325642

RESUMO

A major family of polyadenylylated cytoplasmic transcripts are expressed from the BamHI A-I region of the Epstein-Barr virus genome, off the strand complementary to that encoding several functions associated with viral replication and the lytic cycle, including the DNA polymerase (BALF-5). These complementary-strand transcripts (the main one is about 4.8 kilobases long), expressed in all cell types associated with Epstein-Barr virus, are present at high levels in nasopharyngeal carcinoma tumors. Sequence analysis of clones that correspond to spliced transcripts in a cDNA library from such a tumor, C15, generates a profile of the main complementary mRNA. It contains at least three AUG-initiated open reading frames, the largest of which could be translated to give a polypeptide of about 20 kDa. Evidence from several types of experiments suggests that conditions which support the up (or down) regulation of transcriptional expression from one viral DNA strand within the relevant region of the genome produce the opposite effect on transcripts from the other strand. The capacity for interference between complementary Epstein-Barr viral transcripts offers a mechanism for control of gene expression that may be related to maintenance of viral latency.


Assuntos
Herpesvirus Humano 4/genética , RNA Viral/genética , Infecções Tumorais por Vírus/genética , Sequência de Bases , Carcinoma/genética , Carcinoma/microbiologia , Células Cultivadas , Clonagem Molecular , DNA/genética , Expressão Gênica , Humanos , Dados de Sequência Molecular , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/microbiologia , Oligonucleotídeos/química , RNA Mensageiro/genética
16.
Int J Cancer ; 45(4): 763-72, 1990 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-2157679

RESUMO

The genetic information in a sub-fragment of EBV DNA, designated p31 (containing less than a quarter of the viral genome and derived from a recombinant DNA cosmid library) allows epithelial cells from primary monkey and human kidney cultures to escape senescence under standard tissue culture conditions. A number of epithelial cell lines, designated M1/31, 483/31, 199/31 and HK/31, have been established and characterized following transfection of primary cells with p31 DNA. They share many properties, although morphologically they are not all identical. The cultures are immortalized but not fully transformed or tumorigenic. They appear to be phenotypically stable, although DNA hybridization studies indicate that genotypic alterations, including amplification, occur subsequent to transfection with p31 DNA and the establishment of a continuously proliferating epithelium. All cell lines consistently express high levels of cytokeratin 18 and varying amounts of cytokeratin 7, demonstrating their epithelial origin. From a single marmoset kidney (designated 199) a series of related immortalized cells, with subtle phenotypic differences, have been generated by p31 or sub-fragments of it. Although hallmarks of a "hit-and-run" mechanism are apparent in all of our studies, 2 different techniques (in situ hybridization or selection for cell survival in semi-solid media, followed by nucleic acid hybridization) show that, in late-passaged cultures, a small proportion of the cells still contain some viral DNA. The studies focus on genetic information within the BamHI A and I regions as being relevant to immortalization. The role of the EBV DNA fragment in the genesis of epithelial cell lines is considered.


Assuntos
DNA Viral/genética , Herpesvirus Humano 4/genética , Rim/citologia , Transfecção/genética , Animais , Callithrix , Callitrichinae , Divisão Celular , Linhagem Celular , Sobrevivência Celular , Chlorocebus aethiops , Mapeamento Cromossômico , DNA Viral/análise , Biblioteca Gênica , Humanos
17.
EMBO J ; 8(9): 2639-51, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2479554

RESUMO

A nasopharyngeal carcinoma tumour (designated C15) propagated in nude mice has been used to generate a large cDNA library that we have analysed for Epstein-Barr virus (EBV) gene expression. No gross alterations exist in viral DNA from C15 relative to other human isolates and the large deletion present in the B95-8 'prototype' viral strain established in marmoset cells is not found; C15 contains no linear virion DNA. In the cDNA library, of the six EBV nuclear antigens (EBNAs) expressed in latently infected B-lymphocytes, only clones for EBNA-1 are found. These data are confirmed by immunoblotting. Sequence analysis shows the EBNA-1 mRNA splicing pattern in the carcinoma to differ from that observed in B-lymphocytes. Further, contrary to observations with B-cell lines, most viral transcription in the tumour is localized onto the 'rightmost' region of the conventional EBV physical map. Transcripts identified corresponding to known genes include those for the latent membrane protein (LMP), the alkaline DNA exonuclease and probably the terminal protein; major transcripts are also derived from the BamHI D fragment and the region deleted in B95-8 EBV DNA. Novel transcripts have also been identified that proceed in an anti-sense direction to genes encoding functions associated with replication, such as the viral DNA polymerase. They contain a large, hitherto unidentified, open reading frame in the viral genome that is complementary to the putative function known as BALF3 and a smaller open reading frame complementary to BALF5 (the DNA polymerase gene). From the present studies we can conclude that: (i) EBV transcription patterns in the epithelial cells vary markedly from those identified previously in B-cells, reflecting differential use of promoters or splicing patterns. (ii) Transcription is tightly regulated and restricted in the C15 tumour with many latent genes, notably EBNAs 2-6, being 'switched off.' (iii) A family of cytoplasmic RNAs are transcribed in an antisense direction to a number of existing open reading frames in the EBV genome. (iv) There are a number of mutations in C15 transcripts relative to the B95-8 genome, some of which could result in amino acid alterations in proteins.


Assuntos
Herpesvirus Humano 4/genética , Neoplasias Nasofaríngeas/genética , Sequência de Aminoácidos , Animais , Antígenos Virais/análise , Sequência de Bases , Northern Blotting , Linhagem Celular Transformada , Transformação Celular Viral , Clonagem Molecular , DNA Viral/análise , Expressão Gênica , Humanos , Camundongos , Camundongos Nus , Dados de Sequência Molecular , Neoplasias Nasofaríngeas/análise , Poli A/análise , RNA/análise , RNA Antissenso , RNA Mensageiro/análise
18.
Nature ; 309(5963): 78-82, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6325929

RESUMO

Epstein-Barr virus (EBV) is unique among the DNA tumour viruses by virtue of its association with two human malignancies, Burkitt's lymphoma and nasopharyngeal carcinoma (NPC), the former a tumour of B lymphocytes and the latter encompassing low-differentiated epithelial cells of the nasopharynx. A viral gene product has not been definitively linked to these malignant diseases, although an EBV nuclear antigen(s) (EBNA) seems to be ubiquitous in EBV-infected cells; indeed, the detection of EBNA by immunofluorescence is often taken as an indication of the presence of the viral genome. As part of a study to investigate which part of the EBV genome is responsible for transformation and whether the same mechanism of cellular transformation is involved in the case of B lymphocytes and epithelial cells, we have tried to establish whether a detectable cellular alteration(s) can be induced in primate epithelial cells by the presence of a specific region of the EBV genome. We report here that it can--the result is immortalization of the cells.


Assuntos
Clonagem Molecular , DNA Viral/genética , DNA/genética , Genes Virais , Herpesvirus Humano 4/genética , Animais , Sequência de Bases , Linhagem Celular , Chlorocebus aethiops , Enzimas de Restrição do DNA , Epitélio , Rim , Hibridização de Ácido Nucleico , Transfecção
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