Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019829 (Hodgkin's disease)
 30,247 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Fas ligand (FasL) is capable of inducing apoptosis of lymphoid cells by cross-linking with its natural receptor, Fas. We aimed to investigate the possible role of the Fas/FasL-mediated apoptosis in the development of human lymphomas. FasL mRNA was detected by reverse transcriptase-polymerase chain reaction in 38 out of 63 lymphoma biopsy specimens representative of various subtypes of non-Hodgkin's lymphoma (NHL) and Hodgkin's disease. FasL was co-expressed with Fas mRNA in most cases. Flow cytometry (FACS) analysis showed a bright FasL staining in 31% to up to 75% of the total cell population from 14 out of 16 samples; the presence of the FasL protein was confirmed by Western blotting. Dual-color FACS analysis showed that FasL was expressed by T cells in B-NHLs and T-NHLs. A significant percentage of B cells in various B-NHLs also stained positively for FasL. Freshly separated neoplastic B cells from three FasL+ and one FasL- B-NHLs displayed a relative resistance to Fas-mediated apoptosis, when compared to reactive T cells isolated from the same tissue samples. In contrast, the sensitivity to Fas-mediated killing of the T cells isolated from two FasL+ T-NHLs was not uniform. These data show that (1) FasL is expressed in both neoplastic and reactive cells from a significant proportion of lymphoma cases, and (2) that the intratumoral FasL+/Fas+ reactive T cells are more sensitive to Fas-induced apoptosis than the neoplastic FasL+/Fas+ malignant B cells. A putative defect in the Fas/FasL pathway may thus favor the development of malignant B cell populations.
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PMID:Malignant and reactive cells from human lymphomas frequently express Fas ligand but display a different sensitivity to Fas-mediated apoptosis. 936 20

Fas and Fas ligand expression were investigated in twenty two cases of classical Hodgkin's disease (HD) by immunohistochemistry. While Reed-Sternberg (RS) cells in 7/22 (32%) cases expressed Fas ligand, reactive lymphoid cells expressed Fas ligand in only 2 (9%) cases. In 20/22 (91%) cases, the RS cells expressed Fas. A higher proportion of RS cells in the nodular sclerosis subtype expressed Fas as compared to the mixed cellularity subtype. In 18/22 (82%) cases, Fas expression was also noted in the reactive lymphoid cells. In eight cases, the reactive lymphoid cells were also analyzed by flow cytometry and a majority of them were CD4+CD45RO+. Most of these activated T-cells expressed Fas but were negative for Fas Ligand. To investigate the co-expression of Fas and Fas Ligand in the RS cells, six cases were subjected to Fas and Fas ligand immunostaining on consecutive sections. The co-expression was documented in the RS cells in four of six cases. These six cases with expression of both Fas and Fas ligand were investigated for the incidence of apoptosis. There was no statistically significant relationship between expression of Fas on reactive cells, expression of FasL on RS cells and the proportion of apoptotic reactive cells. In all these cases apoptosis was not observed in the RS cells. Thus Fas - FasL interactions may not lead to apoptosis of the RS cells.
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PMID:Expression of Fas and Fas ligand in Hodgkin's disease. 1034 79

Because previous investigations suggested involvement of the Fas ligand (FasL) in the selection process in the follicular dendritic cell (FDC)-associated cell cluster of the germinal center, we investigated the expression of FasL in Hodgkin lymphoma (HL) on protein and RNA level, while considering the Epstein-Barr virus status of the Hodgkin and Reed-Sternberg (HRS) cells. Tumor tissue from 47 patients with classic HL (32 nodular sclerosis [NS], 11 mixed cellularity [MC], and 4 lymphocyte-rich [LR]) was analyzed by immunohistochemistry for FasL, Fas, CD21, and CD23 and by Western blotting for FasL. FasL mRNA was detected by an exon 4-specific oligonucleotide and Epstein-Barr virus infection by in situ hybridization for Epstein-Barr virus early RNAs (EBER). Western blotting showed soluble and membrane-bound forms of FasL. Immunohistochemistry showed FasL expression in virtually all HRS of 94% of NS cases and 82% of MC cases. FasL expression did not correlate with the Epstein-Barr virus status of the HRS. Low FasL protein expression was found in some HRS of LR cases. FasL mRNA was detected in 39% of NS, 46% of MC, and 33% of LR cases. Seventy percent to 90% of the HRS cells expressed Fas. CD21 immunohistochemistry showed disrupted FDC networks in the tumor tissue with reduced and virtually absent expression of CD23 and FasL. These observations suggest that FasL expression in HRS cells and the absence of FasL in the FDC cluster represent a disturbed microenvironment that may be involved in the pathogenesis of HL.
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PMID:Fas ligand expression in Hodgkin lymphoma. 1122 10

RCAS1 (receptor-binding cancer antigen expressed on SiSo cells) is present in neoplastic cells, induces apoptosis of natural killer (NK)/T cells and plays a role in immune evasion. Fas ligand (FasL) is considered to have similar roles. The Epstein-Barr virus (EBV)-encoded latent membrane protein is expressed by malignant Hodgkin and Reed-Sternberg (H&RS) cells of EBV-associated Hodgkin's disease (HD) and considered to be a target of cytotoxic T lymphocytes (CTLs). However, CTL response is inadequate in HD. To determine whether RCAS1 and FasL are expressed in EBV-associated HD and participate in immune evasion, tissues of 20 EBV(-) and 15 EBV(+) HD cases were immunohistochemically stained for RCAS1, FasL and HLA classes I and II, whose deficiencies could explain CTL escape. Lymphocytes surrounding H&RS cells tended to be CD4(+) cells and rarely CD8(+), TIA-1(+) (cytotoxic marker) or NK cells. HLA class I and/or II were expressed in all EBV(+) HD cases, and RCAS1-expressing H&RS cells were found in 14/15 (93%) EBV(+) HD cases but only 8/20 (40%) EBV(-) HD cases (p < 0.05). FasL was detected in 9/15 (60%) and 7/20 (35%) EBV(+) and EBV(-) HD cases, respectively. ssDNA-positive (apoptotic) lymphocytes, surrounding H&RS cells, were rarely seen but were present in RCAS1(+) cases (20/22 cases, 91%) rather than negative cases (0/13 cases, 0%) (p < 0.005). Our findings suggest that EBV(+) H&RS cells might evade the host immune response by expressing RCAS1 rather than FasL.
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PMID:Expression of human tumor-associated antigen RCAS1 in Reed-Sternberg cells in association with Epstein-Barr virus infection: a potential mechanism of immune evasion. 1139 27

Against the background of its earliest recognition, programmed cell death (PCD) or apoptosis (A) is presented in its fundamental biological contexts. Techniques of its demonstration are listed. Former original works of the authors encompass designs for genetically engineered oncolytic viruses. Presented here are observations on mesenchymal stromal cells of the bone marrow serving as feeder layers to chronic lymphocytic leukemia (CLL) cells (recently rediscovered elsewhere as subverted "nurse cells" protecting CLL cells from A). A-resistant human melanoma cells are shown to expropriate the Fas ligand to Fas receptor (CD95; APO-1) (FasL-->FasR) system for their autocrine growth loop not only in melanoma cells coexpressing CD95 and its ligand but also in CD95-positive melanoma cells undergoing divisions when exposed to CD95 ligand. Bi-directional A-induction is demonstrated upon the encounter of cytotoxic lymphocytes and targeted tumor cells as exemplified with lymphomas; and chemotherapy-induced A of malignant cells as exemplified by paclitaxel-induced PCD of Reed-Sternberg (RS) cells in a case of chemotherapy-resistant Hodgkin's disease (HD). A list of interventions capable of inducing A in tumor cells is provided. These interventions are of potential therapeutic value. The balance of apoptotic and anti-apoptotic forces in virally infected normal and malignant cells is discussed.
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PMID:Virological and immunological connotations of apoptotic and anti-apoptotic forces in neoplasia. 1149 24

Recent reports have demonstrated that EBV can be used as a target of specific CTL-based treatments in severe chronic EBV, immunoblastic B cell lymphoma and Hodgkin's disease (HD). Based upon the promising results form these in vivo studies, it has been suggested that an antigen-specific CTL-based immunotherapy may be of benefit in treating EBV-associated tumors such as HD and nasopharyngeal carcinoma (NPC) which express the potentially immunogenic antigens, LMP1 and LMP2a. Recent work form our group has demonstrated that LMP2a-specific CTLs may be generated in vitro using autologous antigen presenting cells which have been transfected with polyadenylated LMP2a RNA in the presence of a cationic lipid. In this study, we demonstrate that the presence of the lipid enhances dendritic cell (DC) transfection efficiency and appears to protect the intracellular LMP2a RNA from degradation by cellular RNAses. Significantly, these improvements resulted in the transfected DCs having a superior ability to stimulate autologous T cell proliferation. These LMP2a + DCs were used to stimulate LMP2a-specific effector cells which were predominantly a mixture of cytotoxic and helper CD4+ T cells. The molecular mechanisms whereby these CD4+ T cells lyzed their LMP2a-expressing targets was investigated and we show that, although expressing Fas ligand on their surface, LMP2a-specific CD4+ effector cells kill their targets using the Ca2+-dependent perforin/granzyme pathway which is the same mechanism used by CD8+ CTLs.
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PMID:Antigen presenting cells transfected with LMP2a RNA induce CD4+ LMP2a-specific cytotoxic T lymphocytes which kill via a Fas-independent mechanism. 1240 Jun 9

Among the systems triggering apoptosis, the Fas-Fas ligand (FasL) system is recognized as a major pathway for the induction of apoptosis in cells and tissues. Ligation of Fas by either an agonistic antibody or FasL transmits a 'death signal' to the target cell, potentially triggering apoptosis. Alterations of genes along the Fas-mediated apoptosis pathway have been reported in many human cancers. However, there have been no data regarding FasL gene mutations in human cancers. We hypothesized that FasL gene mutation might be involved in the development of non-Hodgkin lymphoma (NHL). In this study, we analyzed the entire coding region of the FasL gene for the detection of somatic mutations in a series of 111 NHLs and found that one tumor had a FasL gene mutation in the cytoplasmic domain. To evaluate the functional alterations of the mutant in apoptosis, we overexpressed the mutant in 293T cells, but couldn't find any significant loss of cell death compared to the wild-type FasL. Together, these data suggest that FasL is occasionally mutated in human NHL and that FasL mutations appear to play no role in the pathogenesis of the vast majority of NHLs.
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PMID:Mutational analysis of Fas ligand gene in human non-Hodgkin lymphoma. 1278 May 24

Hodgkin's lymphoma (HL) is characterized by the presence of malignant so-called Hodgkin's/Reed-Sternberg (HRS) cells, which display resistance to certain apoptotic stimuli, including a lack of sensitivity to Fas-mediated cell death. However, the mechanisms responsible for their resistance to apoptosis inducers have not been elucidated. Here we confirm that both HL-derived cell lines and the HRS cells of primary HL tissues express Fas ligand (FasL) along with the inhibitory c-FLIP protein. Down-regulation of cellular FLICE (FADD-like IL-1beta-converting enzyme)-inhibitory protein (c-FLIP) through the use of specific small inhibitory RNAs (siRNAs) leads to reduced viability of the L428 and L591 HL-derived cell lines. To determine whether endogenous FasL was responsible for the reduction in cell viability observed after down-regulation of c-FLIP, L428 and L591 cells were treated with c-FLIP-specific siRNAs with and without siRNAs directed to FasL. Treatment of these cells with both c-FLIP- and FasL-specific siRNAs in combination restored cell viability to near control levels. Our results provide a mechanism whereby HRS cells are protected from autonomous FasL-mediated cell death while preserving their ability to evade immunosurveillance. Targeting c-FLIP could provide a novel approach to the treatment of HL.
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PMID:Expression of the cellular FLICE-inhibitory protein (c-FLIP) protects Hodgkin's lymphoma cells from autonomous Fas-mediated death. 1509 87

Autoimmune Lymphoproliferative Syndrome (ALPS) is generally the result of a mutation in genes associated with apoptosis, like Fas, Fas ligand, Casp 8 and Casp 10. As a result, the normal homeostasis of T- and B-lymphocytes is disturbed and a proliferation of polyclonal T lymphocytes occurs. This leads to hepatosplenomegaly and lymphadenopathy and in most patients also to autoimmune phenomena like anemia and thrombocytopenia. The proliferating T cells are TCRalphabeta and/or TCRgammadelta positive but lack both CD4 and CD8. Hence they are termed double negative (DN) T cells. In addition, there is an increase of CD5 positive B cells. Individuals with germline mutations in the Fas gene have a high risk to develop non Hodgkin lymphomas (x 14) as well as Hodgkin lymphomas (x 51), in particular NLP Hodgkin lymphoma. Somatic mutations of Fas are frequently acquired during the normal germinal center reaction. Non Hodgkin lymphomas carry somatic mutations of the Fas gene in 11% and of the Casp 10 gene in 14.5% of the patients. In Hodgkin lymphomas, Fas mutations can be demonstrated in Reed-Sternberg cells in 10-20% of the patients. These data implicate a role for Fas-mediated apoptosis in preventing lymphomas. Inherited defects in receptor-mediated lymphocyte apoptosis represent a risk factor for lymphomas and somatic mutations of these genes may also play a role in the development and/or progression of lymphomas.
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PMID:Development of lymphoma in Autoimmune Lymphoproliferative Syndrome (ALPS) and its relationship to Fas gene mutations. 1516 Sep 2

The clinical efficacy of the CD20-specific chimeric monoclonal antibody rituximab is significantly hampered by intrinsic or acquired resistance to therapy. Rituximab activates antibody-dependent cellular cytotoxicity/complement-dependent cytotoxicity-dependent lysis but also induces apoptosis by cross-linking of its target antigen CD20. Recent reports indicate that this apoptotic activity of rituximab can be synergized by cotreatment with Fas agonists. Here, we report on a strategy designed to exploit and optimize the synergy between rituximab and Fas signaling by genetically fusing a rituximab-derived antibody fragment to soluble Fas ligand (sFasL). The resultant fusion protein, designated scFvRit:sFasL, potently induced CD20-restricted apoptosis in a panel of malignant B-cell lines (10 of 11) and primary patient-derived malignant B cells (two of two non-Hodgkin lymphoma and five of six B cell chronic lymphocytic leukemia). ScFvRit:sFasL efficiently activated CD20 and Fas apoptotic signaling, resulting in a far superior proapoptotic activity compared with cotreatment with rituximab and Fas agonists. ScFvRit:sFasL lacked activity toward normal human B cells and also lacked systemic toxicity in nude mice with no elevation of aspartate aminotransferase and alanine aminotransferase levels or liver caspase-3 activity. In conclusion, scFvRit:sFasL efficiently activates CD20 and Fas-apoptotic signaling and may be useful for the elimination of malignant B cells.
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PMID:Superior activity of fusion protein scFvRit:sFasL over cotreatment with rituximab and Fas agonists. 1819 57


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