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)

A novel association, Epstein-Barr virus-positive Ki-1+/CD30+ anaplastic large cell non-Hodgkin's lymphoma of B-cell phenotype in immunosuppressed renal transplant recipients is reported. Case 1 involved an aggressive clinical evolution, whereas case 2 followed a more "benign" clinical course. Both lymphomas were Epstein-Barr virus-positive as assessed by in situ hybridization, Southern blot, polymerase chain reaction, and immunohistochemical analysis. Both lymphomas contained a single clonal Epstein-Barr virus terminal-repeat fragment. In case 1, clonality was confirmed by the detection of bi-allelic immunoglobulin (Ig) heavy chain gene rearrangement. Case 2 showed germline Ig genes at presentation and oligoclonal Ig heavy chain gene rearrangements at relapse. These results are consistent with the notion that anaplastic large cell lymphoma might arise in a B cell transformed by Epstein-Barr virus at a very early stage, before Ig gene rearrangement. The latter may occur later in the course of clonal evolution, thus permitting investigators to trace intermediate and late stages within a process of multistep lymphomagenesis and/or tumor progression.
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PMID:Epstein-Barr virus-associated anaplastic large cell lymphoma in renal transplant patients. 132 90

Nasopharyngeal carcinoma develops with extremely high incidence in discrete populations and geographic locations. It is consistently associated with the ubiquitous Epstein-Barr herpesvirus (EBV). The structure of EBV DNA indicates that the tumor is a clonal proliferation that developed subsequent to EBV infection. Specific viral genes are consistently expressed within all cells of the tumor. This consistent expression may indicate that the viral gene products are required for tumor growth. Genetic or environmental factors may affect the expression of these critical viral genes or cellular genes and contribute to tumor progression.
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PMID:Epstein-Barr virus infection in nasopharyngeal carcinoma. 136 43

E-cadherin is a Ca(2+)-dependent cell adhesion molecule which plays an important role in normal growth and development via mediation of homotypic, homophilic cell-cell interaction. Recent studies suggest that E-cadherin may be important in neoplastic progression as well, particularly as a suppressor of invasion. We have previously demonstrated that the invasive phenotype of rat prostate cancer cells is associated with the decreased expression of E-cadherin (M. J. G. Bussemakers, R. J. A. Van Moorselaar, L. A. Giroldi, T. Ichikawa, J. T. Isaacs, F. M. J. Debruyne, and J. A. Schalken, Cancer Res., 52:2916-2922, 1992). This is of particular interest, since the locus to which the human E-cadherin gene is mapped is frequently involved in allelic loss in prostate cancer (B. S. Carter, C. M. Ewing, W. S. Ward, B. F. Treiger, T. W. Aalders, J. A. Schalken, J. I. Epstein, and W. B. Isaacs, Proc. Natl. Acad. Sci. USA, 87:8751-8755, 1990; U. S. Bergerheim, K. Kunimi, V. P. Collins, and P. Ekman, Genes, Chromosomes Cancer, 3: 215-220, 1991). Impaired E-cadherin function is likely to be associated with aberrant expression of the protein. We therefore analyzed E-cadherin expression in situ by immunohistochemistry in nonmalignant and malignant specimens of human prostatic tissue. Of 92 tumor samples of either primary or metastatic deposits of prostate cancer, 46 had reduced or absent E-cadherin staining when compared to nomalignant prostate, which uniformly stained strongly positive. There was a statistically significant correlation between the decreased expression of E-cadherin and loss of tumor differentiation. Additionally, certain tumors within a histologically similar group could be distinguished by the presence of mixed populations of E-cadherin-negative and -positive cells. The percentage of tumors with aberrant E-cadherin staining increased when clinically localized tumors were compared to either tumors with extensive local progression or metastatic deposits of prostate cancer, suggesting a correlation between loss of E-cadherin and tumor progression. Taken together, these findings suggest that further exploration of E-cadherin as a candidate invasion suppressor molecule in human prostate cancer is warranted.
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PMID:Expression of the cellular adhesion molecule E-cadherin is reduced or absent in high-grade prostate cancer. 151 67

Available evidence suggests that, among hematological malignancies, p53 is most often mutated in Burkitt's lymphoma (BL). However, much of the published data is based on cell lines. We have, therefore, analyzed BL biopsies to determine more accurately the frequency and pattern of p53 mutations in primary tumors and to determine whether there are differences among the various subtypes of BL. Among 27 BL biopsies from South Africa, we have observed mutations in the p53 gene (exons 5 through 8) in 37% of tumors. The higher frequency of mutations in cell lines (70%) suggests that mutation of p53 may be associated with tumor progression. Summarizing available data we conclude that the presence of mutated p53 in BL is independent of the geographic origin of the tumor, the 8;14 chromosomal breakpoint locations and Epstein-Barr virus association. We also find that the mutational spectrum of p53 in BL differs from that observed in nonlymphoid tumors. More than 50% of mutations in BL are clustered in a small stretch of 33 amino acids (codons 213 to 248). Interestingly, codon 213 appears to be as frequently mutated as codon 248. Conversely, codon 273, often mutated in solid tumors, is rarely involved in BL.
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PMID:The pattern of p53 mutations in Burkitt's lymphoma differs from that of solid tumors. 163 40

Tonsils seem to be the ideal source of lymphocytes seeding to the mucosa of the respiratory tract. The distribution and engraftment of human lymphocytes injected into mice with severe combined immunodeficiency (SCID) are not well understood. C.B-17 SCID mice were injected intraperitoneally with human tonsillar mononuclear cells (hu-TMC). The hu-TMC-SCID mouse chimeras were subsequently tested for the appearance and distribution of human lymphocytes tagged with H33342 and immunoglobulin-secreting cells in various systemic and mucosal immunocompetent tissues. This was done by fluorescence microscopy of tissue sections for cells supravitally stained before transfer and by an enzyme-linked immunospot assay using cells isolated from murine organs. Most importantly, engraftment of hu-TMC proved to be dependent on the presence of anti-Epstein-Barr virus (EBV) antibody in the donor. hu-TMC engrafted, in decreasing numbers, in the following systemic organs: peritoneal cavity, liver, spleen and bone marrow. Among mucosal tissues tested, hu-TMC were seen in lungs, but not in the intestines. The engraftment of hu-TMC in the lung was more extensive than that in the spleen. These studies demonstrate that hu-TMC engraft in a variety of murine tissues. The striking preference of hu-TMC for the lungs when compared to intestines suggests selective engraftment among distinct mucosal tissues. The hu-TMC-SCID mouse chimera promises to be a unique animal model to study human-mucosa-associated lymphoid cells and EBV-related lymphomagenesis and B cell tumor progression.
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PMID:Distribution and engraftment patterns of human tonsillar mononuclear cells and immunoglobulin-secreting cells in mice with severe combined immunodeficiency: role of the Epstein-Barr virus. 166 36

In contrast to its role in B-lymphomagenesis, Epstein-Barr Virus (EBV) only incidentally has been associated with T-cell lymphomas. In the present report we describe a fourth patient with EBV-related T-cell lymphoma. The patient presented with an angio-immunoblastic lymphadenopathy (AILD)-like T-cell lymphoma. Serology was compatible with chronic Epstein-Barr (EBV) infection. After a 1-year period of waxing and waning lymphadenopathy, this lymphoma evolved to an aggressive CD8+ Immunoblastic T-cell lymphoma. A relationship with the chronic EBV infection was indicated by the finding of EBV genome in the tumor tissue by Southern blot analysis. Moreover, EBV nuclear antigen (EBNA) was detected in situ within individually defined CD8+ tumor cells by two-color immunofluorescence. Two alternative possibilities, namely that EBV primarily played a role in lymphomagenesis of the AILD-like T-cell lymphoma or that the virus was an additional oncogenic event in the final process of tumor progression to the immunoblastic lymphoma, are discussed.
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PMID:Epstein-Barr virus in a CD8-positive T-cell lymphoma. 216 17

Posttransplant lymphoproliferative disorders (PTLDs) were diagnosed in 43 patients from the Pittsburgh-Denver series between June 1980 and March 1987. This constitutes a detection rate of 1.7%. Major categories of clinical presentation included a mononucleosislike syndrome, gastrointestinal/abdominal disease, and solid organ disease. The median time of onset in patients initially immunosuppressed with cyclosporine-A (CsA)-containing regimens was 4.4 months after transplant, regardless of tumor clonality. A strong association of PTLD with Epstein-Barr virus (EBV) was observed. A histologic spectrum of lesions from polymorphic to monomorphic was observed. Whereas polymorphic lesions could be either clonal or nonclonal, monomorphic lesions appeared to be clonal in composition. The presence of large atypical cells (atypical immunoblasts) or necrosis did not appreciably worsen the prognosis. Twelve patients had clonal, 13 had nonclonal, and five had both clonal and nonclonal tumors. Clonality was indeterminate in 13 cases. Most patients were treated with a regimen based on reduced immunosuppression and supportive surgery. Almost all nonclonal and about half of the clonal lesions respond to this conservative therapy, indicating that it is an appropriate first line of treatment. This behavior suggests that a spectrum of lesions ranging from infectious mononucleosis to malignant lymphoma constitutes the entity known as PTLD. Some monoclonal tumors can undergo regression, however, apparently in response to host immune control mechanisms. Because of its short latency and strong association with EBV, PTLD is an important model for the study of virus-associated tumor progression in humans.
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PMID:The pathology of posttransplant lymphoproliferative disorders occurring in the setting of cyclosporine A-prednisone immunosuppression. 284 89

An abnormal increase in numbers of CCGG sites methylated in the 5' region of the human calcitonin (CT) gene occurred in tumor cell DNA samples from 90% (17 of 19) of patients with non-Hodgkin's T and B cell lymphoid neoplasms and in 95% (21 of 22) of tumor cell DNA samples from patients with acute nonlymphocytic leukemia (ANLL). The changes were not seen in patients with chronic myelogenous leukemia (0 of 9). The abnormal methylation patterns appear to be a property only of transformed or malignant cells since they were not found in DNA from nonneoplastic adult tissues including sperm, early myeloid progenitor cells, benign lymphoid hyperplasia, peripheral lymphocytes stimulated to divide, or early myeloid progenitor cells (obtained by immunoaffinity using anti-My-10 antibody), but they did appear after Epstein-Barr virus transformation of lymphocytes. Moreover, during the course of therapy in patients with ANLL, the hypermethylation pattern reflects the presence of the leukemic clone even in normal-appearing granulocytes derived from this clone. The increased methylation of the CT gene may then provide an important molecular marker for biologic events in human cell transformation or tumor progression and may prove clinically useful in monitoring patients with lymphoid and acute myelogenous neoplasms.
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PMID:Hypermethylation of the 5' region of the calcitonin gene is a property of human lymphoid and acute myeloid malignancies. 360 79

Epstein-Barr virus (EBV) can induce uncontrolled B lymphocyte proliferation leading to fatal lymphoma in immunocompromised patients. The sensitivity to apoptosis of B lymphoid cell lines (LCL) derived from EBV-induced lymphoproliferative disorders was investigated. In vitro and in vivo, these B LCL strongly express CD95/Apo-1/fas antigen and undergo apoptosis upon stimulation with anti-Apo-1 monoclonal antibody. When inoculated into severe-combined immunodeficient (scid) mice, human B cells lines developed into rapidly growing tumors. Administration of an agonistic anti-Apo-1 antibody significantly delayed tumor progression. Relapses were frequent, but were not caused by selection of resistant B cells, since B cells from relapsing tumors underwent apoptosis on re-exposure. Induction of apoptosis by an anti-C95/Apo-1/fas-specific antibody could be applied for therapy of EBV-induced B cell tumors and contribute to our understanding of the mechanisms of T cell-mediated elimination of EBV lymphomas in immunodeficient patients.
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PMID:Sensitivity of Epstein-Barr virus-induced B cell tumor to apoptosis mediated by anti-CD95/Apo-1/fas antibody. 904 28

Extranodal oral lymphomas, seen with increasing frequency in HIV infection, may have dysfunctional apoptotic mechanisms that favor tumor progression. The purpose of this study was to evaluate extranodal lymphomas from HIV-positive patients for expression of apoptosis-associated proteins. Correlations were made with 10 histologically comparable extranodal lymphomas from HIV-negative patients and 6 hyperplastic lymph nodes from otherwise healthy young adults. Formalin-fixed tissue sections were immunohistochemically stained for apoptosis-associated proteins (Bcl-2, Bcl-x, Bax, Bak, p53, MDM2, BHRF). In situ hybridization was also done on deparaffinized sections for Epstein-Barr virus EBER mRNA. Eighteen consecutive oral lymphomas were studied in HIV/AIDS-positive patients. Four of 5 intermediate-grade lymphomas expressed Bcl-2 to a greater degree than did high-grade lymphomas (4 of 13). Most lymphomas were positive for Bcl-x and Bax, and few expressed Bak. The staining patterns for these proteins were similar to those seen in HIV-negative patients. Staining patterns were relatively consistent in the hyperplastic lymph nodes, whereas such patterns were irregular in lymphomas. Positive p53 staining was seen in 11 of 18 HIV-positive cases; 9 of these were also MDM2-positive. Double stains suggested that both p53 and MDM2 proteins were expressed in the same cells in these nine cases. Epstein-Barr virus-EBER mRNA was detected in 14 of 18 cases and in 3 of 10 cases from HIV-negative patients. BHRF staining was evident in only a few cells of three HIV-positive lymphomas. The irregular expression of Bcl-2, Bcl-x, Bax, and Bak in oral lymphomas indicates dysfunctional apoptotic mechanisms in these tumors. Bcl-2 staining differs with tumor grade. Positive staining for p53 and MDM2 proteins is a notable feature of lymphomas in HIV-positive patients and may relate to binding of MDM2 to wild-type p53. Epstein-Barr virus is more commonly associated with oral lymphomas in HIV-positive patients, although the Epstein-Barr virus-produced protein BHRF, which has Bcl-2-like activity, is minimally expressed.
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PMID:Apoptosis-associated proteins in oral lymphomas from HIV-positive patients. 972 96


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