Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0178874 (tumor progression)
 40,807 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have examined avian leukosis virus-induced B-cell lymphomas for multiple, stage-specific oncogene activations. Three targets for viral integration were identified: c-myb, c-myc, and a newly identified locus termed c-bic. The c-myb and c-myc genes were associated with different lymphoma phenotypes. The c-bic locus was a target for integration in one class of lymphomas, usually in conjunction with c-myc activation. The data indicate that c-myc and c-bic may act synergistically during lymphomagenesis and that c-bic is involved in late stages of tumor progression.
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PMID:Multiple proto-oncogene activations in avian leukosis virus-induced lymphomas: evidence for stage-specific events. 254 84

The LAZ3 gene encodes a novel zinc-finger protein that shares homology with several Drosophila transcription factors. This gene was identified by its disruption in translocations involving chromosome 3q27 in diffuse large-cell lymphomas. To assess the frequency and role of this gene's involvement in lymphomagenesis and tumor progression, we examined a series of 170 cases of non-Hodgkin's lymphomas of B-cell lineage for LAZ3 gene rearrangement, expression, and mutation. The cases included 35 de novo diffuse aggressive lymphomas (DAL; 19 large-cell, 4 mixed-cell, and 12 large-cell immunoblastic), 52 transformed aggressive lymphomas derived from follicular lymphomas (TFL), 42 indolent follicular lymphomas (FL), 14 mantle cell lymphomas (MCL), and 27 small noncleaved cell lymphomas (SNCL). LAZ3 rearrangements were found in 10 DAL (28.6%), 9 TFL (17.3%), and 6 FL (14.3%), but not in any of the SNCL or MCL. LAZ3 rearrangement was not exclusive of bcl-2 rearrangement. Most rearrangement breakpoints mapped to a 10-kb BamHI-Xba I fragment located 5' to the LAZ3 coding sequence, consistent with previously reported breakpoint locations. Northern analysis of both rearranged and nonrearranged B-cell lymphoma cases showed similar levels of a transcript of approximately 3.8 kb, indicating that LAZ3 is broadly expressed in B-cell tumors and is not confined to rearranged cases. To investigate whether mutation of the LAZ3 gene might contribute to a potential role for this gene in lymphomagenesis, we screened the coding sequences of 13 rearranged cases, 6 nonrearranged cases, and 13 hematopoietic tumor cell lines. Although three probable polymorphisms were identified, mutations were detected in only 2 rearranged cases. Only 1 of these resulted in an amino acid substitution. Two cell lines (SU-DHL4 and Molt-4) also contained mutations; only one resulted in an amino acid substitution. We conclude (1) that LAZ3 rearrangements occur in a significant fraction of de novo DAL as well as in a smaller subset of indolent and transformed follicular lymphomas; (2) that LAZ3 message is expressed in both rearranged and nonrearranged B-cell lymphomas; and (3) that mutation of the LAZ3 gene does not contribute to its putative oncogenic role in most 3q27 translocated B-cell lymphomas.
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PMID:Analysis of LAZ3 (BCL-6) status in B-cell non-Hodgkin's lymphomas: results of rearrangement and gene expression studies and a mutational analysis of coding region sequences. 774 50

Interactions between cancer cells and laminin, a major component of basement membranes, are mediated through a large variety of cell surface proteins designated as laminin receptors. Among the above proteins, a 67-kd monomeric high affinity laminin receptor (67 LR) has long been suspected to be involved in tumor progression. In this study we wished to establish whether the 67 LR molecule is detectable on tumor cells of Hodgkin's disease (HD) and non-Hodgkin's lymphomas (NHLs), to define its pattern of expression, and to assess the potential utility of 67 LR in differentiating these pathological entities. Morphological and immunohistological studies were performed on 85 specimens of HD and a series of 334 NHL specimens, including anaplastic large cell (ALC) (CD30-positive) lymphomas (73 specimens). For immunohistochemical assessment of the 67 LR we used the monoclonal antibody (MoAb) MLuC5 directed against the 67-kd laminin receptor on paraffin-embedded sections. Reed-Sternberg cells reacted with MLuC5 MoAb in four of 85 (4.7%) HD specimens. Among the NHL specimens, a MLuC5-positive reaction was expressed in 3.3% of B-cell lymphomas. They all belonged to the high grade subtypes. On the other hand, a MLuC5-positive reaction was detected in none of the T-cell lymphomas tested. In contrast to the results obtained with the other NHLs, in 30.2% of ALC (CD30-positive) lymphoma specimens, tumor cells reacted with MLuC5 MoAb. MLuC5-expressing ALC (CD30-positive) lymphoma cells were of either T-cell (six of 17 specimens), B-cell (three of 25 specimens), or undetermined phenotype (10 of 31 specimens). Our investigation has shown that 67 LR as shown by MLuC5 MoAb is detectable only in neoplastic cells of a fraction of ALC (CD30-positive) lymphomas and small subsets of B-cell high grade NHLs and HD. The restricted expression of the 67 LR molecule to ALC (CD30-positive) lymphomas provides a potential tool for the phenotypic separation of this pathological entity from HD and other lymphomas. Whether the detection of the 67 LR expression in these lymphoma subsets may be related to the aggressiveness of the disease remains to be ascertained.
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PMID:Expression of the monomeric 67-kd laminin-binding protein in human lymphomas as defined by MLuC5 monoclonal antibody and paraffin section immunohistochemistry. 1008 60

The BCL-2 gene is the prototype of a newly described family of oncogenes involved in tumorigenesis by blocking apoptosis, or programmed cell death. Overexpression of BCL-2 protein was originally described in follicular B-cell lymphomas bearing the 14;18 translocation. BCL-2 overexpression has also been described in other lymphomas and more rarely in neoplasms outside the lymphoid tissue. The aim of this paper is to determine the immunohistochemical expression of BCL-2 in intradermal nevi and primary invasive and metastatic melanoma. Formalin-fixed and paraffin-embedded tissues from 4 cutaneous melanoma metastases, 10 primary invasive melanomas, and 10 intradermal melanocytic nevi were immunolabeled with monoclonal antibodies directed against BCL-2 protein (Dako, clone 124) and Ki-67 antigen (Amac, clone MIB-1), after antigen retrieval techniques. Morphologically normal epidermal melanocytes expressed BCL-2, as did nevi and melanomas in virtually all cells. However, whereas the labeling in normal melanocytes and nevus cells showed a uniformly strong reactivity, melanoma cells showed a variable but mainly weak reactivity. Ki-67 antigen expression was restricted to melanomas. The widespread expression of BCL-2 suggests that this oncoprotein cannot be involved in the malignant transformation of melanocytic cells. It seems likely that the decreased BCL-2 expression detected in melanomas may reflect one further step of tumor progression in melanocytic neoplasms.
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PMID:Immunohistochemical expression of BCL-2 in melanomas and intradermal nevi. 786 49

We analyzed the production and the roles of IL-6, IL-10, and IL-13 in B-lymphoid malignancies and in specific diseases with B-lymphocyte hyperactivity. Both IL-13 and IL-10 genes are expressed in B-cell lymphomas. However, their contribution to tumor progression is unclear. In certain lymphoproliferative disorders that develop in transplanted patients, IL-6 is produced by malignant cells and is a major factor of their proliferation. In other lymphomas, the IL-6 gene is expressed only in malignancies where differentiated malignant cells are present. In these lymphomas, IL-6 is produced by stromal cells, and the malignant cells express the IL-6 receptor. In patients with HIV infection, the level of production of IL-6, IL-10, and IL-13 is not higher than those of other conditions with immune activation. However, IL-6 contributes to increased production of IgG and IgA in vivo. In Castleman's disease, IL-6 is produced in the lymph node germinal centers, partly originating from follicular dendritic cells, which may explain some of the pathogenesis of this disease. In systemic lupus erythematosus, the critical cytokine is IL-10, which is produced in large amounts by B lymphocytes and monocytes and is responsible for autoantibody production. Taken together, these data emphasize the roles of IL-6 and IL-10, usually produced by nonlymphoid cells, on B lymphocytes, either malignant or hyperactivated.
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PMID:Production and roles of IL-6, IL-10, and IL-13 in B-lymphocyte malignancies and in B-lymphocyte hyperactivity of HIV infection and autoimmunity. 899 99

The bic locus is a common retroviral integration site in avian leukosis virus (ALV)-induced B-cell lymphomas originally identified by infection of chickens with ALVs of two different subgroups (Clurman and Hayward, Mol. Cell. Biol. 9:2657-2664, 1989). Based on its frequent association with c-myc activation and its preferential activation in metastatic tumors, the bic locus is thought to harbor a gene that can collaborate with c-myc in lymphomagenesis and presumably plays a role in late stages of tumor progression. In the present study, we have cloned and characterized two novel genes, bdw and bic, at the bic locus. bdw encoded a putative novel protein of 345 amino acids. However, its expression did not appear to be altered in tumor tissues, suggesting that it is not involved in oncogenesis. The bic gene consisted of two exons and was expressed as two spliced and alternatively polyadenylated transcripts at low levels in lymphoid/hematopoietic tissues. In tumors harboring bic integrations, proviruses drove bic gene expression by promoter insertion, resulting in high levels of expression of a chimeric RNA containing bic exon 2. Interestingly, bic lacked an extensive open reading frame, implying that it may function through its RNA. Computer analysis of RNA from small exon 2 of bic predicted extensive double-stranded structures, including a highly ordered RNA duplex between nucleotides 316 and 461. The possible role of bic in cell growth and differentiation is discussed in view of the emerging evidence that untranslated RNAs play a role in growth control.
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PMID:bic, a novel gene activated by proviral insertions in avian leukosis virus-induced lymphomas, is likely to function through its noncoding RNA. 903 77

Mantle-cell lymphoma comprises 2%-10% of all non-Hodgkin's lymphomas (NHLs). Patients present with generalized disease, and have a poor prognosis. Three different histologic patterns (mantle zone, nodular, and diffuse) and three different cytological variants (classical, blastic, and pleomorphic) have been described. The phenotype (strong surface IgM, CD5+, CD10-, CD23-, cyclin D1+ and B-cell markers+) is remarkably constant. Dependent on the methods used (PCR, Southern blot analysis, and cytogenetics) a t(11;14) can be detected in approximately 35%-66% of cases. Using FISH analysis, possibly almost all cyclin D1-expressing MCLs carry this translocation, indicating that a substantial part of these translocations are missed by conventional methods. This has been confirmed by DNA fiber FISH analysis by which the breakpoints could be accurately mapped over a 220 kb region centromeric of the cyclin D1 gene. Additional genetic abnormalities involve breakpoints and deletion at the 3' end of the cyclin D1 gene, numerical chromosomal aberrations, mutations in p53, and deletions of p16. These may be associated with tumor progression. Owing to the translocation t(11;14), the cyclin D1 gene is activated. At the RNA level, approximately 90% of MCLs show overexpression. This corroborates immunohistochemistry on paraffin tissue sections. Since expression of cyclin D1 in normal lymphoid cells is very low to undetectable, and only hairy-cell leukemia and very few other B-cell lymphomas show expression, immunohistochemistry for cyclin D1 provides an excellent marker for MCL. In hairy-cell leukemia, expression is moderate and cannot be explained by chromosomal translocation.
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PMID:Bcl-1/cyclin D1 in malignant lymphoma. 920 53

Chromosomal translocations leading to deregulation of specific oncogenes characterize approximately 50% of cases of diffuse large B-cell lymphomas (DLBL). To characterize additional genetic features that may be of value in delineating the clinical characteristics of DLBL, we studied a panel of 96 cases at diagnosis consecutively ascertained at the Memorial Sloan-Kettering Cancer Center (MSKCC) for incidence of gene amplification, a genetic abnormality previously shown to be associated with tumor progression and clinical outcome. A subset of 20 cases was subjected to comparative genomic hybridization (CGH) analysis, which identified nine sites of chromosomal amplification (1q21-23, 2p12-16, 8q24, 9q34, 12q12-14, 13q32, 16p12, 18q21-22, and 22q12). Candidate amplified genes mapped to these sites were selected for further analysis based on their known roles in lymphoid cell and lymphoma development, and/or history of amplification in tumors. Probes for six genes, which fulfilled these criteria, REL (2p12-16), MYC (8q24), BCL2 (18q21), GLI, CDK4, and MDM2 (12q13-14), were used in a quantitative Southern blotting analysis of the 96 DLBL DNAs. Each of these genes was amplified (four or more copies) with incidence ranging from 11% to 23%. This analysis is consistent with our previous finding that REL amplification is associated with extranodal presentation. In addition, BCL2 rearrangement and/or REL, MYC, BCL2, GLI, CDK4, and MDM2 amplification was associated with advanced stage disease. These data show, for the first time, that amplification of chromosomal regions and genes is a frequent phenomenon in DLBL and demonstrates their potential significance in lymphomagenesis.
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PMID:Chromosomal and gene amplification in diffuse large B-cell lymphoma. 963 22

The CDKN2A gene located on chromosome region 9p21 encodes the cyclin-dependent kinase-4 inhibitor p16/INK4A, a negative cell cycle regulator. We analyzed p16/INK4A expression in different types of non-Hodgkin's lymphoma to determine whether the absence of this protein is involved in lymphomagenesis, while also trying to characterize the genetic events underlying this p16/INK4A loss. To this end, we investigated the levels of p16/INK4A protein using immunohistochemical techniques in 153 cases of non-Hodgkin's lymphoma, using as reference the levels found in reactive lymphoid tissue. The existence of gene mutation, CpG island methylation, and allelic loss were investigated in a subset of 26 cases, using single-strand conformational polymorphism and direct sequencing, Southern Blot, polymerase chain reaction, and microsatellite analysis, respectively. Loss of p16/INK4A expression was detected in 41 of the 112 non-Hodgkin's lymphomas studied (37%), all of which corresponded to high-grade tumors. This loss of p16/INK4A was found more frequently in cases showing tumor progression from mucosa-associated lymphoid tissue low-grade lymphomas (31 of 37) or follicular lymphomas (4 of 4) into diffuse large B-cell lymphomas. Analysis of the status of the p16/INK4A gene showed different genetic alterations (methylation of the 5'-CpG island of the p16/INK4A gene, 6 of 23 cases; allelic loss at 9p21, 3 of 16 cases; and nonsense mutation, 1 of 26 cases). In all cases, these events were associated with loss of the p16/INK4A protein. No case that preserved protein expression contained any genetic change. Our results demonstrate that p16/INK4A loss of expression contributes to tumor progression in lymphomas. The most frequent genetic alterations found were 5'-CpG island methylation and allelic loss.
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PMID:Loss of p16/INK4A protein expression in non-Hodgkin's lymphomas is a frequent finding associated with tumor progression. 973 37

The molecular genetic hallmark of mantle cell lymphomas (MCL) is the reciprocal translocation t(11;14)(q13;q32) which juxtaposes the bcl-1 proto-oncogene to one of the joining segments of the immunoglobulin heavy chain gene. This translocation is very common in MCL and occurs in up to 70% of these malignancies. Due to the aggressive nature of MCL, markers identifying tumor progression and clinical outcomes are necessary. In this study we examined whether a corroborative relation exists between p53 mutations, bcl-1 translocation, and the proliferative fraction in MCL. We evaluated the proliferative fraction, p53 gene status, and bcl-1 translocation in 21 patients with confirmed MCL. Controls consisted of normal DNA and 7 B-cell lymphomas. Immunohistochemical detection of Ki-67 was used to assess proliferative activity while molecular techniques were used to detect p53 mutations and the bcl-1 gene translocation. Reactivity to the monoclonal antibody Ki-67 on neoplastic cells ranged from 5% to 40% in typical MCL cases. The bcl-1 gene translocation was detected by PCR in 48% (10/21) of MCLs while no rearrangements were detected by PCR in case control DNA. Screening exons 5-8 of the p53 gene for mutations did not identify a single mutation in any of the MCL cases. No correlation was found between p53 mutations, the presence of a bcl-1 translocation, and the proliferative activity of neoplastic MCL cells. We conclude that these markers may demonstrate independent events which occur during the pathogenesis of MCL.
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PMID:Proliferative fraction, bcl-1 gene translocation, and p53 mutation status as markers in mantle cell lymphoma. 1008 8


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