Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Six cases of mediastinal large B-cell lymphoma (MLCL) with sclerosis were analyzed for the presence and patterns of c-myc and bcl-2 loci rearrangements, and for the presence of Epstein-Barr virus DNA sequences by Southern blot hybridization, c-myc gene alterations were found in three of six cases. Two cases showed the presence of mutations or small rearrangements at the 3' end of the first exon. The c-myc gene abnormalities found in these two cases are similar to those observed in the translocation 8;14 of the endemic Burkitt's lymphomas or in its variants t(2;8) and t(8;22). A third case showed a major rearrangement of c-myc gene, with truncation within its first intron, similar to those observed in sporadic Burkitt's and in acquired immunodeficiency-associated lymphomas. None of the cases displayed bcl-2 gene rearrangements or contained viral sequences. Our data suggest a possible role for a translocation-mediated c-myc activation in the pathogenesis of MLCL. Conversely, bcl-2 gene and Epstein-Barr virus do not appear to be involved in the pathogenesis of these peculiar lymphomas. The association between c-myc structural modifications and MLCL also seems to be of relevance in light of the peculiar tendency of this tumor to involve unusual extranodal site (eg, kidney), reminiscent of the spreading attitude of Burkitt's limphomas.
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PMID:Evidence of c-myc gene abnormalities in mediastinal large B-cell lymphoma of young adult age. 153 62

Transgenic mice carrying the exogenous c-myc gene under regulation of the Ig enhancer (Ig-c-myc) were mated with mice carrying exogenous c-fos gene under control of the H-2Kb promoter (H2-c-fos) to examine their functional collaboration in in vivo lymphomagenesis. Two of the 33 (c-fos x c-myc) mice developed pre-B cell lymphomas within 22 weeks of age. None of the other F1 progeny expressing c-fos or c-myc alone showed malignant change within 14 months of age, suggesting that the exogenous c-fos and c-myc collaborate in in vivo lymphomagenesis. The exogenous c-myc RNA was overexpressed in the lymphomas, but the amount of exogenous c-fos RNA was not affected, suggesting that the large abundance of c-myc protein is a prerequisite for lymphoma onset or progression and c-fos protein plays a complementary role. C-fos protein induced immunodeficiency in the (c-fos x c-myc) mice like H2-c-fos mice. Natural killer cell activity of (c-fos x c-myc) mice was partially impaired. Therefore, these lymphomas may be a consequence of the synergism of two independent actions caused by the exogenous c-myc (lymphomagenesis) and the exogenous c-fos (low NK activity) in (c-fos x c-myc) mice.
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PMID:Possible collaboration between c-fos and c-myc proto-oncogene products in in vivo lymphomagenesis. 172 94

High-grade non-Hodgkins B-cell lymphoma is one of the principle malignancies that occurs in individuals infected with the human immunodeficiency virus (HIV-1). Immunoblastic lymphomas that arise in immunosuppressed transplant patients have been described as both monoclonal and polyclonal, and occur in association with Epstein-Barr virus (EBV) infection. To test whether polyclonal lymphoma occurred in patients with AIDS we studied tumors from multiple sites in three patients who died with widespread AIDS-associated large cell or large cell immunoblastic lymphoma. All biopsy specimens contained invasive lymphoma. Tumor cells were mature IgM-positive immunoblasts by immunohistochemical analysis, with the same B-cell phenotype observed in all tumor sites. Only a minority of sites from all patients analyzed were monoclonal as measured by immunoglobulin gene rearrangements, with one case having several foci of monoclonal disease with other histologically identical metastases showing no evidence of monoclonal proliferation. Similar to the transplant-associated polyclonal B-cell proliferations. EBV gene sequences were present in multiple sites from one autopsy. In the other two autopsies, polyclonal B-cell proliferations occurred in the absence of EBV involvement except at one site, where a minor clone of EBV-infected cells was found. In contrast to HIV-associated Burkitt's lymphoma, no c-myc rearrangements were found at any site. These studies describe the occurrence of polyclonal lymphoma in AIDS and suggest that EBV-negative polyclonal lymphoma may be a distinct disease entity unique to HIV-infected individuals.
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PMID:AIDS-associated polyclonal lymphoma: identification of a new HIV-associated disease process. 184 89

A DNA-binding factor with properties of NF-kappa B and another similar activity are rapidly induced when growth-arrested BALB/c 3T3 cells are stimulated with serum growth factors. Induction of these DNA-binding activities is not inhibited by pretreatment of quiescent cells with the protein synthesis inhibitor cycloheximide. Interestingly, the major NF-kappa B-like activity is not detected in nuclear extracts of proliferating cells, and thus its expression appears to be limited to the G0-to-G1 transition in 3T3 cells. These DNA-binding activities bind many of the expected NF-kappa B target sequences, including elements in the class I major histocompatibility complex and human immunodeficiency virus enhancers, as well as a recently identified NF-kappa B binding site upstream of the c-myc gene. Furthermore, both the class I major histocompatibility complex and c-myc NF-kappa B binding sites confer inducibility on a minimal promoter in 3T3 cells stimulated with serum growth factors. The results demonstrate that NF-kappa B-like activities are immediate-early response proteins in 3T3 cells and suggest a role for these factors in the G0-to-G1 transition.
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PMID:Induction of NF-kappa B DNA-binding activity during the G0-to-G1 transition in mouse fibroblasts. 192 27

Forty-six fine-needle aspirates of lymphoproliferative lesions from 31 human immunodeficiency virus (HIV)-positive patients were reviewed using cytomorphologic, immunocytochemical, flow cytometric (FCM), cytogenetic, and molecular studies. There were 29 lymphomas (15 small non-cleaved cell [SNCL], 11 large cell [LCL], one small lymphocytic, and two Hodgkin's), 14 reactive hyperplasias, and three "atypical lymphoid proliferations." The reactive hyperplasias were characteristically polymorphic and polyclonal lymphoid populations; six of seven were diploid on FCM, the seventh was hypodiploid. Higher proliferative indices (mean, 11.6%) and higher RNA indices (mean, 1.2) characterized this subgroup compared with published reactive lymphoid hyperplasias from patients without HIV positivity. Aspirates of SNCL showed monotonous populations of intermediate-sized cells except in one patient where a giant cell syncytial variant occurred. Nine of 13 SNCL aspirates showed light chain restriction. JH rearrangement revealed B-cell lineage in one aspirate in which immunocytochemical study was negative for Kappa, lambda, B1, and Leu-4. Nine of 12 SNCL were diploid; the mean proliferative index was 25.6% and the mean RNA index 2.3. Chromosomal translocations involving the c-myc locus were demonstrated in five of seven SNCL aspirates karyotyped. Five of eight LCL showed light chain restriction the remaining three showed null cell phenotype. Large cell lymphomas were diploid on tetraploid with the mean proliferative index of 22.0% and mean RNA index of 2.2. One of two LCL aspirates karyotyped demonstrated c-myc translocation. Despite the multiparameter approach, a definitive diagnosis could not be reached in three aspirates.
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PMID:Fine-needle aspiration evaluation of lymphoproliferative lesions in human immunodeficiency virus-positive patients. A multiparameter approach. 199 Dec 48

The hepatitis B virus (HBV) X gene product (pX) could be important in disease pathogenesis because it is known to transactivate transcription from many viral and cellular gene promoters, including the HBV core gene promoter, the human immunodeficiency virus (HIV-1) long terminal repeat, and the c-myc promoter. We have previously shown that only a subset of the promoters that can be transactivated by pX is transactivated in any particular cell line, and have proposed that pX acts through multiple, cell type-specific transcription factors. We show here that pX acts through both AP-1 and AP-2 sites, and that pX has a transcription activation domain. We conclude that transactivation by pX depends on at least two distinct cellular DNA-binding transcription factors and we present a model for the action of pX.
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PMID:Transactivation by the hepatitis B virus X protein depends on AP-2 and other transcription factors. 215 3

Four Epstein-Barr virus-positive lymphoblastoid cell lines (LCL) were successfully infected in vitro with immunodeficiency virus type 1 (HIV-1) as demonstrated by reverse transcriptase activity and p24 HIV antigen in culture supernatants, positive cell staining for gag-encoded HIV proteins, presence of viral HIV genome by Southern blot analysis and ulstrastructural observations. In addition, both HIV-1-infected B cells and their supernatants efficiently transactivated the chloramphenicol acetyl transferase reporter gene which is under the control of the HIV-1 long terminal repeat. The LCL cells displayed long-term HIV-1 infection and production, but no cytopathic effects were observed. Cytofluorimetric analysis did not detect membrane CD4 presence in the LCL cells before and after HIV-1 infection; moreover, a minute amount of CD4 mRNA was observed only in one of the LCL. A monoclonal antibody specific for the viral binding site of the CD4 molecule delayed, but did not block, HIV-1 infection of the LCL cells. Following HIV-1 infection, changes in LCL phenotype were observed, consisting of a decrease in CD23- and CD39-positive cells, and a concomitant increase of cells with surface CD10 and Bac-1. Furthermore, HIV-1-infected LCL cells did not grow in tight clumps, as usually observed in uninfected LCL, but as disperse suspensions, and formed more agar colonies than control LCL. However, despite this apparent acquisition of a malignant-like phenotype, c-myc proto-oncogene rearrangement was not detected. The appearance of cells with new characteristics did not seem due to clone selection by HIV-1 infection, since all the LCL conserved their clonotypic pattern of IgH chain rearrangement. The acquisition of malignant-like features by HIV-infected B cells might be clinically significant in terms of the pathogenesis of non-Hodgkin's B cell lymphomas, which occur frequently in AIDS patients.
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PMID:Infection of Epstein-Barr virus-transformed lymphoblastoid B cells by the human immunodeficiency virus: evidence for a persistent and productive infection leading to B cell phenotypic changes. 217 Jan 47

Congenital and acquired states of immunodeficiency have long been associated with an increased incidence of malignant lymphoma. An increased incidence of non-Hodgkin's lymphomas was recognized early in the epidemic immunodeficiency state associated with the human immunodeficiency virus (HIV) infection AIDS. Although the precise etiologic mechanism of these lymphomas remains speculative, the presence of Epstein-Barr viral proteins or sequences and characteristic chromosomal translocations giving rise to altered expression of the c-myc oncogene have frequently been observed. It has been suggested that HIV infection leading to disordered T-lymphocyte function (possibly in conjunction with Epstein-Barr infection) leads to the emergence of polyclonal populations of stimulated B lymphocytes. These cells, which undergo physiologic immunoglobulin gene rearrangement, may provide the background for the occurrence of characteristic chromosomal translocations that lead to the emergence of malignant lymphomas. These lymphomas tend to present clinically with high-grade histopathologic subtype, advanced stage, and a propensity for the involvement of otherwise unusual extranodal sites, including the central nervous system. The experience with therapy for HIV-associated lymphomas has indicated that highly aggressive, dose-intensive chemotherapy regimens may be associated with inferior results. More recent regimens have stressed less myelosuppressive therapy combined with prophylaxis for central nervous system disease and pneumocystis infection. The dominant prognostic factors in the HIV-associated lymphomas appear to be primarily related to the underlying HIV infection and include total CD4 lymphocyte count, performance status, and prior AIDS diagnosis.
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PMID:Acquired immunodeficiency syndrome-associated lymphomas. 218 76

Stringent control of human immunodeficiency virus (HIV) replication was observed in the human monoblastoid cell line U937. A low-multiplicity infection of these cells by the LAV1 strain of HIV was productive for 2.5 days; then virus replication became restricted and no further evidence of virion production was observed. The dramatic decrease in HIV production was due in part of reduced accumulation of cytoplasmic viral RNA and occurred in the absence of evident cytopathic effects. In contrast, infected cells induced to differentiate by phorbol ester, vitamin D3, or lymphokine supernatant did not release markers of HIV despite the accumulation of significant levels of cytoplasmic viral RNA. HIV infection altered the pattern of c-myc RNA accumulation in U937 cells. Expression of this gene changes normally in response to the state of cellular differentiation; in infected cells the level of c-myc expression was correlated to the levels of viral RNA accumulation and not to cellular differentiation. These results suggest that restricted replication of HIV in monocytes might be an important mechanism of virus persistence and demonstrate a relationship between HIV replication and monocyte differentiation.
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PMID:Human immunodeficiency virus infection of monoblastoid cells: cellular differentiation determines the pattern of virus replication. 245 83

The amino acid L-tryptophan is known to be a modulator of many processes of cell metabolism. In this contribution we show that L-tryptophan interferes with some biological effects of the antileukemic and anti-human immunodeficiency virus agent avarol, possibly by different mechanisms. Avarol has been shown to be able to modulate posttranscriptional events of mRNA synthesis, resulting in an increase of the base-sequence complexities of the nonabundant and rare mRNA classes. Here it is demonstrated that this change in mRNA abundancy distribution is accompanied by an increase in the level of some specific, low abundant mRNAs (ras and c-myc). Addition of L-tryptophan was found to abolish avarol-caused gene relaxation in L1210 mouse leukemia cells. In addition, L-tryptophan suppressed the induction of gamma-interferon mRNA production in human peripheral blood lymphocytes. At the level of DNA, L-tryptophan inhibited the production of strand breaks by cytotoxic avarol concentrations in Friend erythroleukemia cells in vitro. Moreover, it competed with avarol for binding to the nuclear envelope binding site; this effect was not shown by other amino acids.
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PMID:Suppression of the modulatory effects of the antileukemic and anti-human immunodeficiency virus compound avarol on gene expression by tryptophan. 249 75


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