• Title/Summary/Keyword: CD95

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Roles of Neutral Sphingomyelinase 1 on CD95-Mediated Apoptosis in Human Jurkat T Lymphocytes

  • Lee, Hyun-Min;Surh, Bo-Young;Chun, Young-Jin
    • Biomolecules & Therapeutics
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    • v.18 no.3
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    • pp.262-270
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    • 2010
  • CD95 receptor is a member of tumor necrosis factor receptor family that mediates apoptosis in many cell types when bound by CD95 ligand or cross-linked by agonistic anti-CD95 antibodies. To determine the role of neutral sphingomyelinase (nSMase) on CD95-mediatd apoptosis, human Jurkat T lymphocytes were exposed to recombinant human CD95 ligand. Treatment with CD95 ligand induced cell death in a concentration and time-dependent manner. CD95-induced cell death was suppressed by inhibitors of SMase such as AY9944 or desipramine. Transfection with human nSMase1 siRNA plasmid into CD95 ligand-treated cells significantly prevented CD95-mediated cell death. CD95-mediated elevation of intracellular ceramide level detected by FACS analysis with anti-ceramide antibody was also decreased by nSMase1 siRNA. Knock-down of nSMase1 expression also blocked cytochrome c release into cytosol and caspase-3 cleavage in CD95-treated cells. Taken together, these results suggest that nSMase1 may play an important role in CD95-mediated apoptotic cell death in Jurkat T cells.

Sensitization of TNFα and Agonistic FAS/CD95 Antibody-Induced Apoptosis by INFγ on Neuroblastoma Cells (신경모세포종에서 IFNγ에 의한 TNFα와 길항적 FAS/CD95항체 유도성 세포고사의 감작화)

  • Bang, Ho Il;Kim, Jong Duck;Choi, Du Young
    • Clinical and Experimental Pediatrics
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    • v.46 no.7
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    • pp.702-709
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    • 2003
  • Purpose : $IFN{\gamma}$ sentitizes many tumor cells to $TNF{\alpha}$ and FASL-mediated apoptosis by enhancing the expression of TNF or FAS/CD95 receptor and modulating the activation of caspase and Bcl-2 family. It has been reported that $IFN{\gamma}$ and $TNF{\alpha}$ synergistically caused differentiation and growth inhibition of neuroblastoma cells. Even though some neuroblastoma cell express FASR/FASL on the cell surface, they could not induce apoptosis by ligation of the FAS/CD95 receptor. But the treatment of $IFN{\gamma}$ is reported to induce apoptosis in some neuroblastoma cell lines through the CD95/CD95L autocrine circuit. In this study, we examined whether $IFN{\gamma}$ could affect $TNF{\alpha}$ and agonistic FAS/CD95 antibody(CH-11)-induced apoptosis against neuroblastoma cell lines that had shown diverse drug sensitivity and resistance. Methods : CHLA-15, CHLA-90 and LA-N-2 neuroblastoma cells were cultured in IMDM and treated with recombinant $IFN{\gamma}$, $TNF{\alpha}$ and CH-11 antibody. Cell viability was measured by DIMSCAN with a fluorescent calcein-AM. Apoptosis was analyzed through flow cytometry using Annexin V-PE and 7-ADD staining and confirmed by pancaspase and caspase-8 blocking experiments. The expression of TNF RI and FAS/CD95 receptor was evaluated by flow cytometry using the corresponding antibody and PE-conjugated secondary antibody. Results : $IFN{\gamma}$ or $TNF{\alpha}$ alone had no demonstrable cytotoxic effects, whereas both cytokines in combination induced apoptosis synergistically in CHLA-15 and CHLA-90 cells. Although there was no cytotoxicity with the ligation of CH-11 alone in CHLA-90 cells, pretreatment of $IFN{\gamma}$ increased the sensitivity of CH-11-mediated apoptosis. The expression of TNFRI and FAS/CD95R were non-specifically enhanced after treatment of $IFN{\gamma}$ without relation to sensitivity to $TNF{\alpha}$ and CH-11. This finding suggest up-regulation of both receptors may contribute to sensitization of $TNF{\alpha}$ and CH-11-mediated apoptosis by $IFN{\gamma}$ in only sensitive cell lines. Conclusion : $IFN{\gamma}$ induced sensitization of $TNF{\alpha}$ and agonistic FAS/CD95 antibody-mediated apoptosis on some neuroblastoma cells through up-regulation of TNFRI and FAS/CD95 receptor.

Apo-1/Fas (CD95) Gene Polymorphism in Korean Knee Osteoarthritis Patients (한국인 무릎 골 관절염 환자들의 임상 양상과 Apo-1/Fas (CD95) 유전자 다형성과의 상관관계에 관한 연구)

  • Hong, Seung-Jae;Yang, Hyung-In;Yim, Sung-Vin;Chung, Joo-Ho;Jung, Young-Ok;Kim, Ho-Youn
    • IMMUNE NETWORK
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    • v.3 no.2
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    • pp.145-149
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    • 2003
  • Background: Apoptosis has been implicated in pathogenesis of various disease. Apo-1/Fas (CD95) is one of the main pathway of apoptosis. To examine the possible relationship between Apo-1/Fas (CD95) and primary knee osteoarthritis, MvaI restriction length polymorphism (RFLP) in human Apo-1/Fas (CD95) gene was assessed. Methods: Genotype and allele frequencies in promoter region in the Apo-1/Fas (CD95) gene were studied by PCR-RFLP in 226 Korean controls and 148 Korean patients with primary knee osteoarthritis. Results: No statistically significant difference in the genotypic distribution and allelic frequencies was found between the control and the knee oateoarthritis patients. But in the severe grade (grade 3, 4) Kellgren-Lawrence score patients, the frequency of $MvaI^*1$ (G) allele was significantly decreased (P=0.0392) and the of $MvaI^*2$ (A) allele frequency was significantly increased (P=0.0473) compared to the normal controls. Conclusion: Apo-1/Fas (CD95) gene polymorphism is a part a determinant factor of severity in knee osteoarthritis, the patients with $MvaI^*2$ (A) allele is more severe radiologic progression. Further substantiation studies are needed in larger patient samples and various other apoptosis related genes to elucidate the mechanism of osteoarthritis, including the Fas ligand gene analysis.

Extracts from Polypodium ferns upregulate the expression of CD95 in human peripheral blood lymphocytes

  • Lombardi, Valter R.M.;Etcheverria, I.;Fernandez-Novoa, L.;Blanco, A.;Diaz, J.;Cacabelos, R.
    • Advances in Traditional Medicine
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    • v.3 no.2
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    • pp.90-99
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    • 2003
  • There are several data in the literature indicating a great variety of pharmacological activities of Polypodium genus, which exhibit antiinflammatory and immunomodulatory activities. Since one of our main interests is to obtain natural immunoregulatory agents devoid of pharmacological adverse effects, we used flow cytometry analysis to highlight relative contributions of a water-soluble fraction of different concentrations of Polypodium rhizome extracts on lymphocyte subpopulations, NK and LAK activity. To measure their potential immunoregulatory activity a T cell proliferation assay in response to phytohemaglutinin (PHA) and mixed lymphocyte reactions were chosen. As a confirmatory bioassay we studied the effect of our extracts on CD45RO and CD95 antigen expressions. The results indicate that CD95 expression dramatically increases after peripheral blood lymphocyte activation and treatment with Polypodium leucotomus, cambricum and vulgare extracts, suggesting a powerful intrinsic pro-apoptotic effect.

Contrasting Prognostic Effects of Tumor-Infiltrating Lymphocyte Density in Cardia and Non-cardia Gastric Adenocarcinomas

  • Kim, Hyoung-Il;Kim, Sang Yong;Yu, Jae Eun;Shin, Su-Jin;Roh, Yun Ho;Cheong, Jae-Ho;Hyung, Woo Jin;Noh, Sung Hoon;Park, Chung-Gyu;Lee, Hyuk-Joon
    • Journal of Gastric Cancer
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    • v.20 no.2
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    • pp.190-201
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    • 2020
  • Purpose: This study sought to investigate the prognostic significance of tumor-infiltrating lymphocytes (TILs) in relation to tumor location within the stomach. Materials and Methods: The densities and prognostic significance of TIL subsets were evaluated in 542 gastric cancer patients who underwent gastrectomy. Immunohistochemical staining for CD3, CD4, CD8, forkhead/winged helix transcription factor (Foxp3), and granzyme B was performed. Results: Cardia cancer was associated with significantly lower densities of CD8 T-cells and higher densities of Foxp3 and granzyme B T-cells than non-cardia tumors. Multivariate analysis showed that advanced age (hazard ratio [HR], 1.023; 95% confidence interval [CI], 1.006-1.040), advanced T classification (HR, 2.029; 95% CI, 1.106-3.721), lymph node metastasis (HR, 3.319; 95% CI, 1.947-5.658), low CD3 expression (HR, 0.997; 95% CI, 0.994-0.999), and a high Foxp3/CD4 ratio (HR, 1.007; 95% CI, 1.001-1.012) were independent predictors of poor overall survival in cardia cancer patients. In non-cardia cancer patients, total gastrectomy (HR, 2.147; 95% CI, 1.507-3.059), advanced T classification (HR, 2.158; 95% CI, 1.425-3.266), lymph node metastasis (HR, 1.854; 95% CI, 1.250-2.750), and a low Foxp3/CD4 ratio (HR, 0.978; 95% CI, 0.959-0.997) were poor prognostic factors for survival. Conclusions: The densities and prognostic effects of TILs differed in relation to the location of tumors within the stomach. The contrasting prognostic effects of Foxp3/CD4 ratio in cardia and non-cardia gastric cancer patients suggests that clinicians ought to consider tumor location when determining treatment strategies.

A Correlative Study on Aβ and CD95 Pathway Independent to Ca2+ Dependent Protease and Activation of Caspase Activation

  • Tuyet, Pham Thi Dieu
    • Journal of Integrative Natural Science
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    • v.7 no.1
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    • pp.25-38
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    • 2014
  • Amyloid-${\beta}$-peptide ($A{\beta}$) is important in the pathogenesis of Alzheimer's disease (AD). Calpain ($Ca^{2+}$-dependent protease) and caspase-8 (the initiating caspase for the extrinsic, receptor-mediated apoptosis pathway) have been implicated in $AD/A{\beta}$ toxicity. We found that $A{\beta}$ promoted degradation of calpastatin (the specific endogenous calpain inhibitor); calpastatin degradation was prevented by inhibitors of either calpain or caspase-8. The results implied a cross-talk between the two proteases and suggested that one protease was responsible for the activity of the other one. In neuron-like differentiated PC12 cells, calpain promotes active caspase-8 formation from procaspase-8 via the $A{\beta}$ and CD95 pathways, along with degradation of the procaspase-8 processing inhibitor caspase-8 (FLICE)-like inhibitory protein, short isoform (FLIPS). Inhibition of calpain (by pharmacological inhibitors and by overexpression of calpastatin) prevents the cleavage of procaspase-8 to mature, active caspase-8, and inhibits FLIPS degradation in the $A{\beta}$-treated and CD95-triggered cells. Increased cellular Ca2+ per se results in calpain activation but does not lead to caspase-8 activation or FLIPS degradation. The results suggest that procaspase-8 and FLIPS association with cell membrane receptor complexes is required for calpain-induced caspase-8 activation. The results presented here add to the understanding of the roles of calpain, caspase- 8, and CD95 pathway in $AD/A{\beta}$ toxicity. Calpain-promoted activation of caspase-8 may have implications for other types of CD95-induced cell damage, and for nonapoptotic functions of caspase-8. Inhibition of calpain may be useful for modulating certain caspase-8-dependent processes.

Prognostic Value of CD44 Variant exon 6 Expression in Non-Small Cell Lung Cancer: a Meta-analysis

  • Zhao, Shuang;He, Jin-Lan;Qiu, Zhi-Xin;Chen, Nian-Yong;Luo, Zhuang;Chen, Bo-Jiang;Li, Wei-Min
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.16
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    • pp.6761-6766
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    • 2014
  • Background: CD44v6 (CD44 variant exon 6) is the chief CD44 variant isoform regulating tumor invasion, progression, and metastasis. The prognostic value of CD44v6 expression in non small cell lung cancer (NSCLC) has been evaluated in many studies, but the results have remained controversial. Thus, we performed a meta-analysis of currently available studies to investigate the prognostic value of CD44v6 expression in NSCLC patients and the relationship between the expression of CD44v6 and clinicopathological features. Materials and Methods: Two independent reviewers searched the relevant literature in Pubmed, Medline and Embase from 1946 to January 2014. Overall survival (OS) and various clinicopathological features were collected from included studies. This meta-analysis was accomplished using STATA 12.0 and Revman 5.2 software. Pooled hazard ratios (HRs) with 95% confidence intervals (95%CIs) were calculated to estimate the effects. Results: A total of 921 NSCLC patients from ten studies met the inclusion criteria. The results showed that CD44v6 high expression was a prognostic factor for poor survival (HR=1.91, 95%CI=1.12-3.26, p<0.05). With respect to clinicopathological features, CD44v6 high expression was related to histopathologic type (squamous cell carcinoma versus adenocarcinoma: OR=2.72, 95%CI=1.38-5.38, p=0.004), and lymph node metastasis (OR=3.02, 95%CI=1.93-4.72, p<0.00001). Conclusions: Our results suggested CD44v6 high expression as a poor prognostic factor for NSCLC, and CD44v6 expression is associated with lymph node metastasis and histopathologic type. Therefore, CD44v6 expression can be used as a novel prognostic marker in NSCLC cases.

Apigenin Increases Natural Killer Cytotoxicity to Human Hepatocellular Carcinoma Expressing HIF-1α through High Interaction of CD95/CD95L

  • Lee, Hwan Hee;Cho, Hyosun
    • Journal of Microbiology and Biotechnology
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    • v.32 no.4
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    • pp.397-404
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    • 2022
  • Natural killer (NK) cell activity is more attenuated in hepatocellular carcinoma (HCC) patients than normal. Hypoxic-inducible factor (HIF)-1α is highly expressed in tumors to maintain their metabolism in a hypoxic environment. The expression of HIF-1α in cancers can lead to cell growth, proliferation, invasion/metastasis and immune escape. Although apigenin, a flavonoid, is known to have various biological activities, it has not been demonstrated in NK cell immune activity in HCC cells. In this study, NK-92 cells were directly cocultured with HCC SK-Hep1 cells for 24 h to evaluate NK cell activity in HCC cells or HCC cells expressing HIF-1α by apigenin. NK cell cytotoxicity to HCC cells expressing HIF-1α was significantly increased, and NK cell-activating receptors, NKG2D, NKp30 and NKp44 were highly expressed. The activating effect of apigenin on NK cells substantially induced apoptosis in HCC cells expressing HIF-1α through high expression of CD95L on the surface of NK-92 cells. Moreover, apigenin excellently inhibited the level of TGF-β1 in a coculture of NK cells and HCC cells. In conclusion, apigenin seems to be a good compound that increases NK cell cytotoxicity to HCC cells by controlling HIF-1α expression.

Soft Linearization of Array-Sensor Characteristics Based on Fuzzy Logic

  • Na, Seung-You;An, Myung-Kook;Shin, Dae-Jung;Lee, Heyoung
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.95.4-95
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    • 2002
  • 1. Introduction 2. Distance measurement using array 3. Linearization of CdS array characteristics 3.1. Crisp linearization of CdS array characteristics 3.2. Fuzzy logic linearization of CdS array characteristics 4. Magnetic Levitation System 4.1. Design of MLS 4.2. Implementation of MLS 4.3. Results of MLS 5. Conclusion

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Three Crystal Structures of Dehydrated $Cd^{2+}$ and $Rb^+$ Exchanged Zeolite A, $Cd_xRb_{12-2x}-A,$ x=4.0, 5.0 and 5.95

  • Song, Yeong-Sim;Kim, Un-Sik;Kim, Yang;Kim, Duk-Soo
    • Bulletin of the Korean Chemical Society
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    • v.11 no.4
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    • pp.328-331
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    • 1990
  • Three crystal structures of dehydrated Cd(II) and Rb(I) exchanged zeolite A, $Cd_{4.0}Rb_{4.0}-A (a = 12.204(3) {\AA}), Cd_{5.0}Rb_{2.0}-A (a = 12.202(1) {\AA}),$ and $Cd_{5.95}Rb_{0.1}-A (a = 12.250(2) {\AA}),$ have been determined by single-crystal X-ray diffraction techniques. Their structures were solved and refined in the cubic space group Pm3m at $21(1)^{\circ}C.$ All crystals were ion exchanged in flowing streams of mixed $Cd(NO_3)_2·4H_2O$ and $RbNO_3$ aqueous solution with total concentration of 0.05 M. All crystals were dehydrated at ca. $450^{\circ}C$ and $2×10^{-6}$ Torr for 2 days. In all of these structures, $Cd^{2+}$ ions are found on threefold axes, each nearly at the center of a 6-oxygen ring. The first three $Rb^+$ ions per unit cell preferentially associate with 8-oxygen rings, and additional $Rb^+$ ions, if present, are found on threefold axes in the large cavity. The final $R_1$ and $R_2$ values for the three structures are 0.087 and 0.079, 0.059 and 0.067, and 0.079 and 0.095, respectively.