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Query: UMLS:C0019693 (HIV)
 170,526 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A new human virus belonging to the herpesvirinae family was recently isolated and characterized. This virus called human herpesvirus 8 is considered as the etiological agent or as a major cofactor of all the clinical forms (HIV associated or not) of Kaposi's sarcoma. HHV8 is also associated with rare B cell lymphomas called body cavity based lymphoma (BCBL) or Primary effusion lymphoma (PEL) occurring in the body cavities mainly in AIDS patients and of some cases of the multicentric form of Castleman's disease. Only preliminary data are available on the epidemiological characteristics (modes of transmission in endemic regions, geographical distribution ...) of the HHV8 infection but should rapidly beneficiate of the establishment of specific and reliable serological tests. Nevertheless, it appears that the HHV8 seroprevalence is very high (15 to 50%) in the adult general population of areas having a high incidence of Kaposi's sarcoma as some east african countries and at a lesser extend as some mediterranean areas as southern Italy or Greece. In the occidental world, the seroprevalence of HHV8 seems very low (0 to 5% in the blood donors) except in some populations at risk for sexually transmitted diseases especially in the homosexual male group. Preliminary data indicate the existence of a low genetic variability of HHV8 in several regions of its genome, with however the presence of molecular subtypes linked possibly to the geographical origin of the infected patients.
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PMID:[Human herpesvirus 8 and associated diseases: Kaposi's sarcoma, body cavity based lymphoma and multicentric Castleman disease: clinical and molecular epidemiology]. 945 29

Primary effusion lymphoma (PEL) is a recently described distinct subtype of non-Hodgkin's lymphoma associated with infection by the Kaposi's sarcoma-associated herpesvirus, also called human herpesvirus-8. Most cases of PEL are also associated with the Epstein-Barr virus (EBV). In order to better characterize the cellular origin of PEL, we investigated the immunoglobulin (Ig) heavy chain variable region (VH,) genes expressed by tumor cells of the BC-1 and BC-3 cell lines derived from PELs and five original PEL specimens. In the six EBV-positive PELs examined, including the BC-1 cell line, the expressed VH gene sequences showed numerous point mutations relative to the putative germline VH gene sequences. In addition, the VH, segment of one of these cases showed intraclonal sequence heterogeneity, indicating ongoing somatic mutation. In five cases, the distribution and type of mutations indicated that tumor cells had been selected by antigen. Because somatically mutated Ig genes are expressed by B cells that have reached a germinal center/post-germinal center stage of development, these findings suggest that the PEL cell of origin is a germinal center or post-germinal center B cell in most cases. In contrast, the VH gene segment expressed by tumor cells of the BC-3 cell line, which was originated from an EBV-negative PEL obtained from an HIV-negative patient, was unmutated, suggesting a pre-germinal center B cell origin for tumor cells of this particular PEL cell line. Taken together, these findings suggest that development of PELs may not be restricted to one stage of B cell differentiation and may represent transformation of B cells at different stages of ontogeny.
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PMID:Immunoglobulin VH gene mutational analysis suggests that primary effusion lymphomas derive from different stages of B cell maturation. 981 22

Human immunodeficiency virus-1 (HIV-1)-Tat, the transactivating gene product of HIV-1, has been shown to interact with different cell types, inducing gene expression, altering their growth and migratory behavior. In this study we examined whether Tat might affect functions of acquired immunodeficiency syndrome (AIDS)-related non-Hodgkin's lymphoma (NHL), relevant to the in vivo dissemination. Our results show that Tat significantly augmented the motility of the two AIDS-related Burkitt's lymphoma cell lines (AS283 and PA682PB) and AIDS-primary effusion lymphoma cell line (HBL-6-AIDS-PEL). Mutations in RGD or basic domain of Tat (KGE-MBP and LxI-MBP, respectively) sharply reduced migration compared with wild type, suggesting that both domains are required for migration. In contrast, a Tat protein mutation outside the active domains (NH(2)-TAT-GST) did not reduce lymphoma cell migration. The treatment of lymphoma cells with Tat did not influence their adhesion to matrix proteins or to human vascular endothelial cells, but endothelial cells treated with Tat became more adhesive to lymphoma cells. Flow cytometric analysis showed that treatment of endothelial cells with Tat induced the cell surface expression of the adhesion molecules vascular cell adhesion molecule-1 (VCAM-1) and E-selectin and increased the expression of intercellular adhesion molecule-1 (ICAM-1). Only antibodies against VCAM-1 on endothelial cells or against the VLA-4 integrin expressed on AS283 cells inhibited the increment of adhesion, indicating the relevance of this pathway in the adhesion of lymphoma cells to vascular endothelium. In our work, we show for the first time that Tat can enhance the migration of lymphoma cells and their adhesion to endothelial cells, two processes that may contribute to the malignant behavior of NHL in patients with AIDS.
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PMID:Human immunodeficiency virus-1 (HIV-1)-Tat protein promotes migration of acquired immunodeficiency syndrome-related lymphoma cells and enhances their adhesion to endothelial cells. 1047

Primary effusion lymphoma (PEL) is a novel lymphoproliferative disorder associated with human herpesvirus 8 (HHV-8) infection. Most PELs develop in HIV-seropositive individuals and are nearly always positive for Epstein-Barr virus (EBV), a finding which obscures the role of HHV-8 in lymphomagenesis. However, rare EBV-negative PEL cases occurring in HIV-seronegative patients have been reported, suggesting that HHV-8 may be pathogenetic by itself. To investigate whether HHV-8 may contribute to PEL development in the absence of EBV, the expression of seven potentially oncogenic HHV-8 open reading frames (ORFs) (ORF72/viral cyclin D, ORF16/viral bcl-2, ORF74/viral G-protein coupled receptor, ORFK2/viral IL-6, ORFK13/viral FLICE inhibitory protein, ORFK9/viral interferon regulatory factor, and ORFK1, equivalent to the gene encoding herpesvirus saimiri transforming protein) was assessed by reverse transcriptase-polymerase chain reaction (RT-PCR) in an EBV-negative PEL presenting in an HIV-negative patient. RNA transcripts were demonstrated for the seven HHV-8 genes, and this was confirmed by hybridization to specific oligonucleotide probes. The expression of potentially oncogenic HHV-8 genes in this HIV-, EBV-negative PEL case suggests that HHV-8 may induce malignant transformation of B-lymphocytes through different molecular pathways in the absence of EBV infection.
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PMID:Expression of potentially oncogenic HHV-8 genes in an EBV-negative primary effusion lymphoma occurring in an HIV-seronegative patient. 1054 88

Primary effusion lymphoma (PEL) is a novel lymphoma entity consistently infected by HHV-8 that occurs predominantly in immunodeficient patients and is characterized by liquid growth in the serous body cavities. In order to facilitate the understanding of PEL pathogenesis and histogenesis, we have established three PEL cell lines termed CRO-AP/2, CRO-AP/3 and CRO-AP/5. All cell lines have been derived from HIV positive homosexual men affected by PEL with (in the case of CRO-AP/2 and CRO-AP/5) or without (in the case of CRO-AP/3) a previous history of Kaposi's sarcoma. The cell lines are representative of both virologic variants of PEL, i.e. HHV-8+ EBV+ PEL (CRO-AP/2 and CRO-AP/5) and HHV-8+ EBV- PEL (CRO-AP/3). Morphologic and phenotypic features of CRO-AP/2, CRO-AP/3 and CRO-AP/5 are typical of PEL, and include morphology bridging immunoblastic and anaplastic features as well as an indeterminate (non B- non T-cell) phenotype. The B-cell nature of the cell lines is documented by the presence of rearranged immunoglobulin genes. The detailed analysis of the molecular and phenotypic features of CRO-AP/2, CRO-AP/3 and CRO-AP/5 has allowed the identification of recurrent chromosomal abnormalities of PEL and has contributed to the definition of PEL as a lymphoma of post-germinal center, pre-terminally differentiated B-cells.
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PMID:Primary effusion lymphoma cell lines harbouring human herpesvirus type-8. 1078 88

Primary effusion lymphoma (PEL) represents a peculiar type of B cell lymphoma which associates with HHV-8 infection and preferentially grows in liquid phase in the serous body cavities. In this report, we provide the detailed characterization of a newly established PEL cell line, termed CRO-AP/6. The cell line was obtained from the pleural effusion of a HIV-positive patient with PEL. Its derivation from the tumor clone was established by immunogenotypic analysis. Detailed phenotypic investigations defined that CRO-AP/6 reflects pre-terminally differentiated B cells expressing the CD138/syndecan-1 antigen. Karyotypic studies of CRO-AP/6 identified several chromosomal abnormalities, whereas genotypic studies ruled out the involvement of molecular lesions associated with other types of B cell lymphoma. Both CRO-AP/6 and the parental tumor sample harbored infection by HHV-8. Conversely, EBV infection was present in the parental tumor sample although not in CROAP/6, indicating that CRO-AP/6 originated from the selection of an EBV-negative tumor subclone. The pattern of viral (HHV-8 v-cyclin) and cellular (p27Kip1) regulators of cell cycle expressed by CRO-AP/6, together with the results of growth fraction analysis, point to abrogation of the physiological inverse relationship between proliferation and p27Kip1 expression. Also, both CRO-AP/6 and the parental tumor sample display biallelic inactivation of the DNA repair enzyme gene O6-methylguanine-DNA methyltransferase (MGMT) by promoter methylation. Overall, the CRO-AP/6 cell line may help understand cell cycle control of PEL cells, may clarify the relative contribution of HHV-8 and EBV to the disease growth and development and may facilitate the identification of recurrent cytogenetic abnormalities highlighting putative novel cancer related loci relevant to PEL.
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PMID:Characterization of a novel HHV-8-positive cell line reveals implications for the pathogenesis and cell cycle control of primary effusion lymphoma. 1091 56

Primary effusion lymphoma (PEL) is a recently described rare type of non-Hodgkin's lymphoma occurring almost exclusively in HIV infected people. Human herpesvirus 8 (HHV-8), has been linked with PEL, and a causative relationship has been suggested. In the vast majority of PEL cases Epstein-Barr virus (EBV) has been found in the tumour cells. We describe here an elderly human immune deficiency (HIV) seronegative man with intractable chest pain and pleural effusion. The diagnosis of malignant lymphoma was suggested cytologically and confirmed histologically following pleural biopsy. No lymphadenopathy or organ involvement with lymphoma was found. Systemic chemotherapy with a modified CHOP regimen with G-CSF support gradually led to the resolution of the chest pain and ultimately resulted in a complete clinical remission (CCR). The presence of HHV-8 was demonstrated by PCR using paraffin-embedded tissue samples from the involved pleura, whereas EBV-associated genetic material was absent. The patient remained in CCR for 18 months and died of an unrelated cause (cerebrovascular event). Only 11 other cases with clinical and virological features similar to those of our patient have been reported in the literature. Analysis of these rare cases suggests HIV-negative EBV-negative PEL to be a distinct clinical entity with epidemiological features resembling classical KS and supports an EBV-independent role for HHV-8 in the pathogenesis of PEL.
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PMID:Primary effusion lymphoma (PEL) in HIV-negative patients--a distinct clinical entity. 1137 60

Pneumothorax occurs in 1 to 2% of hospitalized patients with HIV and is associated with 34% mortality. Pneumocystis carinii pneumonia and chest radiographic evidence of cysts, pneumatoceles, or bullae are risk factors for spontaneous pneumothorax. Tube thoracostomy, pleurodesis, and surgical treatment are usually needed to manage spontaneous pneumothorax in AIDS. Pleural effusion is seen in 7 to 27% of hospitalized patients with HIV infection. Its three leading causes are parapneumonic effusions, tuberculosis, and Kaposi sarcoma. Pleural effusions occur in 15 to 89% of cases of pulmonary Kaposi sarcoma and in 68% of cases of thoracic non-Hodgkin lymphoma in patients with AIDS. Primary effusion lymphoma accounts for 1 to 2% of non-Hodgkin lymphomas. Kaposi sarcoma and primary effusion lymphoma are associated with human herpesvirus 8. The prognosis of patients with pleural Kaposi sarcoma and non-Hodgkin lymphoma in AIDS is poor, and the major goal of treatment is palliation.
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PMID:Pleural effusions and pneumothoraces in AIDS. 1147 Sep 75

Primary effusion lymphoma (PEL) is recognized as a unique lymphoma entity, which occurs exclusively in body cavities as a serous lymphomatous effusion without tumor formation or organ infiltration. We established a cell line of B-cell origin from a pericardial effusion of a 63-year-old Japanese PEL patient who did not have human immunodeficiency virus infection. This PEL cell line had human herpesvirus-8 (HHV-8) and Epstein-Barr virus (EBV) infection. We named this cell line RM-P1. This cell line showed complex chromosomal abnormalities that could not be identified by G-banding. However, spectral karyotyping analysis determined the origin and organization of all unidentified chromosomal abnormalities. When inoculated into the peritoneal cavity of 8 severe combined immunodeficiency (SCID) mice depleted of natural killer cells, RM-P1 cells induced solid tumor with ascites in all animals tested. These tumor and ascitic cells had the same immunogenotypic features as those of the original RM-P1. These 2 types of cells were positive for both HHV-8 and EBV as demonstrated using polymerase chain reaction. Fluorescence-activated cell sorting analyses showed that neither tumors nor ascitic cells grown in SCID mice expressed leukocyte function-associated antigen (LFA)-1alpha (CD11a), LFA-1lbeta (CD18), LFA-2 (CD2), LFA-3 (CD58), intercellular adhesion molecule (ICAM)-1 (CD54), ICAM-2 (CD102), ICAM-3 (CD50), or leukocyte endothelial adhesion molecule (LECAM)-1 (CD62L), suggesting that these cytoadhesion molecules are not involved in tumor formation of RM-P1 cells in vivo. The establishment of the RM-P1 cell line and the animal model of PEL may provide insights for understanding the relationship between these viruses and PEL and for understand the mechanism for PEL.
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PMID:Establishment of a primary effusion lymphoma cell line (RM-P1) and in vivo growth system using SCID mice. 1221 16

Primary effusion lymphoma is a form of diffuse large B-cell lymphoma with neoplastic cells largely limited to proliferation within major body cavities. Human herpes virus-8 is both integral to and required for an unequivocal diagnosis of primary effusion lymphoma. Prior methods for virus identification include DNA extraction with Southern blot analysis or in situ hybridization from paraffin-embedded samples. Our aim is to examine the utility of human herpesvirus-8 identification performed directly on smears from effusion samples by reverse transcriptase in situ polymerase chain reaction in patients with primary effusion lymphoma. Smears and cell block of body cavity fluids from five patients with effusions (three pleural, one peritoneal, and one both pleural and peritoneal) were examined microscopically by conventional Papanicolaou and Romanowsky (Diff-Quik) staining, and by reverse transcriptase in situ polymerase chain reaction for human herpesvirus-8 detection. In situ hybridization was performed also for Epstein-Barr virus (EBER-1, -2), T-cell receptor-beta, and kappa (kappa) and lambda (lambda) mRNA in all cases. Five adults ranged from 40-81 years of age. Three adults were HIV positive, one was a renal transplant recipient, and the oldest patient (Case 3) had the unusual distinction of a normal immune status. Two of three HIV-seropositive patients had concurrent Kaposi sarcoma. All samples were cytologically similar with lymphocytes having large-cell, plasmablastic, and immunoblastic morphology. Malignant cells from effusions were as follows: human herpesvirus-8 positive (all five cases), exhibited kappa monoclonal light chain (five cases), Epstein-Barr virus positive (three cases), and T-cell beta-gene receptor positive (two cases). Diffuse large B-cell lymphoma was evident in one peritoneal nodule (< 10% human herpesvirus-8 positive cells in contrast to > 90% positive in effusions, all kappa positive). Six other tissue specimens (lung, bone marrow, spleen, lymph node) were human herpesvirus-8 negative, and showed no evidence of lymphoma. Reverse transcriptase in situ polymerase chain reaction demonstrated near-complete restriction of human herpesvirus-8-infected malignant lymphoid cells to those in body cavities. Definitive diagnosis of primary effusion lymphoma is possible directly from cytologic smears/cell block by combining cytologic morphology with reverse transcriptase in situ polymerase chain reaction detection of human herpesvirus-8.
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PMID:Primary effusion lymphoma: cytopathologic diagnosis using in situ molecular genetic analysis for human herpesvirus 8. 1221 12


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