OBJECTIVE: To investigate the expression of apoptosis related protein cellular Fas associated death domain like interleukin 1 converting enzyme inhibitory protein (c-FLIP) in peripheral blood mononuclear cells (PBMCs) of patients with rheumatoid arthritis and its relation with extrinsic apoptotic pathway. METHODS: Sixty patients with rheumatoid arthritis were collected from Zhangzhou Affiliated Hospital of Fujian Medical University during January 2014 and June 2015, including 22 patients with low activities (DAS28<3.2), 20 patients with middle activities (3.2 ≤ DAS28 ≤ 5.1), and 18 patients with high activities (DAS28>5.1). And 25 healthy controls were also collected. The mRNA and protein expression levels of c-FLIP and the extrinsic apoptotic pathway related proteins Fas-associated protein with death domain (FADD), caspase-8 in PBMCs were detected by real-time RT-PCR and Western blot, respectively. Correlations between c-FLIP and FADD, caspase-8 in PBMCs were analyzed by pearson test. RESULTS: mRNA expression levels of c-FLIP, FADD and caspase-8 in PBMCs of patients with rheumatoid arthritis were all higher than those of healthy controls (all <0.05). mRNA expression levels of FADD and caspase-8 in patients with middle activities were significantly higher than those in patients with low activities (all <0.05), but the mRNA expression level of c-FLIP was not significantly higher than that in patients with low activities. mRNA expression level of c-FLIP in patients with high activities was higher than those in patients with middle or low activities (all <0.05), while the mRNA expression level of caspase-8 was lower than those in patients with middle or low activities (all <0.05). mRNA expression level of FADD in patients with high activities was higher than those in patients with low activities (<0.05). Pearson analysis showed that there was a positive correlation between c-FLIP and FADD mRNA expression (=0.323, <0.05), and negative correlation between c-FLIP and caspase-8 mRNA expression (-1.104, <0.05). The protein expression levels of c-FLIP and FADD in patients with middle activities were significantly higher than those in control group and patients with low or high activities (<0.05 or 0.01). The protein expression levels of caspase-8 in patients with middle and high activities were significantly higher than those in control group and patients with low activities (<0.05 or <0.01), and the protein expression level of caspase-8 in patients with high activities was higher than that in patients with middle activities (<0.05). CONCLUSIONS c-FLIP may be involved in the extrinsic apoptotic pathway in rheumatoid arthritis, and can provide reference for the evaluation of disease activities.
Apoptosis ; genetics ; Arthritis, Rheumatoid ; blood ; CASP8 and FADD-Like Apoptosis Regulating Protein ; genetics ; Gene Expression Profiling ; Gene Expression Regulation ; Humans ; Leukocytes, Mononuclear ; metabolism

OBJECTIVETo examine the expression of FLICE-inhibitory protein (FLIP) in juvenile idiopathic arthritis (JIA) and analyze its correlation with synovial inflammation.

METHODSThe expression of FLIP was assessed in 11 JIA and 3 normal synovial tissue samples by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry. The cell types expressing FLIP were further characterized, and the correlation of FLIP expression with the degree of synovial inflammation, as well as the activity of caspase 8 was then analyzed.

RESULTSRT-PCR revealed the expression of FLIP mRNA in all 11 JIA samples, but not in 3 normal synovial tissues. In JIA, FLIP expression could be found in both the lining and sublining layers, mainly in the macrophage-like cells. Moreover, the expression of FLIP in JIA synovial tissues was positively correlated with the degree of synovial inflammation (r = 0.563, P < 0.05).

CONCLUSIONThe expression of antiapoptotic FLIP in JIA synovial tissue and its correlation to accumulation of inflammatory cells in synovial tissue suggests that FLIP potentially extends the lifespan of synovial cells and thus contributes to the progression of joint destruction.

Adolescent ; Arthritis, Juvenile ; metabolism ; pathology ; CASP8 and FADD-Like Apoptosis Regulating Protein ; genetics ; metabolism ; Caspase 8 ; metabolism ; Child ; Female ; Humans ; Inflammation ; metabolism ; pathology ; Male ; Protein Isoforms ; genetics ; metabolism ; Synovial Membrane ; cytology ; metabolism ; pathology

This study was aimed to investigate the expression of c-FLIPL, c-FLIPS and DLK1 mRNA in the patients with myelodysplastic syndrome (MDS) and its clinical significance. The mRNA expression of c-FLIPL, c-FLIPS and DLK1 in bone marrow mononuclear cells (BMMNC) of 16 patients with MDS and 3 controls were detected by RT-PCR. The results indicated that the expression of DLK1 mRNA was up-regulated in MDS, including RA and RAEB, as compared with controls (p < 0.05). There was no significant difference in expression of DLK1 between RA and RAEB patients (p > 0.05); the expression of c-FLIPL mRNA both in RA and RAEB patients was higher than that in controls (p < 0.05). There was no significant difference in expression of c-FLIPL between RA and RAEB patients (p > 0.05); the expression of c-FLIPS mRNA was not significantly different between MDS patients and controls (p > 0.05), but its expression in RAEB patients was significantly higher as compared with RA patients and controls (p < 0.05). It is concluded that the mRNA expressions of DLK1, c-FLIPL and c-FLIPS in MDS patients are abnormal, some of which may be useful as an important indicator for the evaluation of development in MDS.
Aged ; Bone Marrow Cells ; metabolism ; CASP8 and FADD-Like Apoptosis Regulating Protein ; genetics ; metabolism ; Case-Control Studies ; Female ; Gene Expression ; Humans ; Intercellular Signaling Peptides and Proteins ; genetics ; metabolism ; Male ; Membrane Proteins ; genetics ; metabolism ; Myelodysplastic Syndromes ; genetics ; RNA, Messenger ; genetics

OBJECTIVETo investigate the efficacy and mechanisms of recombinant adenovirus containing c-FLIPs (cellular FLICE-inhibitory protein short) in inducing antiapoptosis activation of lymphocyte in vitro.

METHODSc-FLIPs gene was cloned from total RNA of lymphocyte with RT-PCR methods, then constructed recombined adenovirus Ad.c-FLIPs by pAdeasy system. H9 cells infected with Ad.c-FLIPs produced antiapoptosis derived from anti-Apo-1 antibody, and those antiapoptosis evaluated with PI stain flow cytometry (FCM) and Hoechst stain.

RESULTSc-FLIPs gene was successfully cloned from lymphocytes and incorporated into recombinant adenovirus Ad.c-FLIPs.After exposure to anti-Apo-1 for 24 h, the apoptosis of H9 cells preconditioned by Ad.c-FLIPs for 24 h as measured by Hochst stain or FCM significantly decreased, compared with non-preconditioned cells, 3.60% +/- 0.21% vs. 48.33% +/- 7.41%, respectively, indicating that Ad.c-FLIPs preconditioning protected H9 cells against apoptosis induced by anti-Apo-1.

CONCLUSIONRecombinant adenovirus Ad.c-FLIPs effectively induced anti-apoptosis activation of lymphocyte.

Adenoviridae ; genetics ; Apoptosis ; physiology ; CASP8 and FADD-Like Apoptosis Regulating Protein ; genetics ; physiology ; CD4-Positive T-Lymphocytes ; cytology ; metabolism ; Cell Line ; Flow Cytometry ; Humans ; Lymphocytes ; cytology ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Transfection ; fas Receptor ; analysis

Synthetic oligodeoxynucleotides (ODN) with a CpG-motif are recognized by Toll-like receptor 9 (TLR9) and pleiotropic immune responses are elicited. Stimulation of macrophages with TLR9 agonist prevented apoptosis induced by serum deprivation through increased expression of FLICE-like inhibitory protein (FLIP). CpG ODN-mediated anti-apoptosis depended on the TLR9-Akt-FoxO3a signaling pathway. Inhibition of TLR9 by small interfering (si) RNA or an inhibitor suppressed CpG ODN-mediated anti-apoptosis. Analysis of signaling pathways revealed that the anti-apoptotic effect of CpG ODN required phosphorylation of FoxO3a and its translocation from the nucleus to the cytosol. Overexpression of FoxO3a increased apoptosis induced by serum deprivation and CpG ODN blocked these effects through FLIP expression. In contrast, siRNA knock-down of FoxO3a decreased apoptosis by serum deprivation. In addition, Akt activation was involved in CpG ODN-induced phosphorylation of FoxO3a, expression of FLIP, and anti-apoptosis. Taken together, these results demonstrate the involvement of Akt-FoxO3a in TLR9-mediated anti-apoptosis and indicate that FoxO3a is a distinct regulator for FLIP expression.
Animals ; *Apoptosis ; CASP8 and FADD-Like Apoptosis Regulating Protein/*genetics/metabolism ; Cells, Cultured ; Forkhead Transcription Factors/genetics/*metabolism ; Macrophages/metabolism ; Mice ; Mice, Inbred C57BL ; Oligodeoxyribonucleotides/metabolism ; Oncogene Protein v-akt/metabolism ; RNA, Small Interfering/metabolism ; Signal Transduction ; Toll-Like Receptor 9/genetics/*metabolism

Tumor necrosis factor-related apoptosis-induced ligand (TRAIL) induces apoptosis selectively in cancer cells while sparing normal cells. However, many cancer cells are resistant to TRAIL-induced cell death. Here, we report that paxilline, an indole alkaloid from Penicillium paxilli, can sensitize various glioma cells to TRAIL-mediated apoptosis. While treatment with TRAIL alone caused partial processing of caspase-3 to its p20 intermediate in TRAIL-resistant glioma cell lines, co-treatment with TRAIL and subtoxic doses of paxilline caused complete processing of caspase-3 into its active subunits. Paxilline treatment markedly upregulated DR5, a receptor of TRAIL, through a CHOP/GADD153-mediated process. In addition, paxilline treatment markedly downregulated the protein levels of the short form of the cellular FLICE-inhibitory protein (c-FLIPS) and the caspase inhibitor, survivin, through proteasome-mediated degradation. Taken together, these results show that paxilline effectively sensitizes glioma cells to TRAIL-mediated apoptosis by modulating multiple components of the death receptor-mediated apoptotic pathway. Interestingly, paxilline/TRAIL co-treatment did not induce apoptosis in normal astrocytes, nor did it affect the protein levels of CHOP, DR5 or survivin in these cells. Thus, combined treatment regimens involving paxilline and TRAIL may offer an attractive strategy for safely treating resistant gliomas.
Antineoplastic Agents/*pharmacology ; Apoptosis/*drug effects ; Astrocytes/metabolism ; CASP8 and FADD-Like Apoptosis Regulating Protein/genetics/*metabolism ; Caspase 3/metabolism ; Cell Line, Tumor ; Drug Discovery ; Flow Cytometry ; Glioma/*metabolism/pathology ; Humans ; Indoles/*pharmacology ; Inhibitor of Apoptosis Proteins/metabolism ; RNA, Small Interfering ; Receptors, TNF-Related Apoptosis-Inducing Ligand/genetics/metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; TNF-Related Apoptosis-Inducing Ligand/metabolism/*pharmacology ; Transcription Factor CHOP/analysis

This study was designed to investigate the effects of the prenylated flavonoid kurarinone on TNF-related apoptosis inducing ligand (TRAIL)-induced apoptosis and its underlying mechanism. A low dose of kurarinone had no significant effect on apoptosis, but this compound markedly promoted tumor cell death through elevation of Bid cleavage, cytochrome c release and caspase activation in HeLa cells treated with TRAIL. Caspase inhibitors inhibited kurarinone-mediated cell death, which indicates that the cytotoxic effect of this compound is mediated by caspase-dependent apoptosis. The cytotoxic effect of kurarinone was not associated with expression levels of Bcl-2 and IAP family proteins, such as Bcl-2, Bcl-xL, Bid, Bad, Bax, XIAP, cIAP-1 and cIAP-2. In addition, this compound did not regulate the death-inducing receptors DR4 and DR5. On the other hand, kurarinone significantly inhibited TRAIL-induced IKK activation, IkappaB degradation and nuclear translocation of NF-kappaB, as well as effectively suppressed cellular FLICE-inhibitory protein long form (cFLIPL) expression. The synergistic effects of kurarinone on TRAIL-induced apoptosis were mimicked when kurarinone was replaced by the NF-kappaB inhibitor withaferin A or following siRNA-mediated knockdown of cFLIPL. Moreover, cFLIP overexpression effectively antagonized kurarinone-mediated TRAIL sensitization. These data suggest that kurarinone sensitizes TRAIL-induced tumor cell apoptosis via suppression of NF-kappaB-dependent cFLIP expression, indicating that this compound can be used as an anti-tumor agent in combination with TRAIL.
Antineoplastic Agents/*pharmacology ; Apoptosis/*drug effects ; CASP8 and FADD-Like Apoptosis Regulating Protein/*genetics/metabolism ; Caspase 3/metabolism ; Caspase 8/metabolism ; Drug Synergism ; Enzyme Activation/drug effects ; Flavonoids/*pharmacology ; Gene Expression/drug effects ; Gene Knockdown Techniques ; HeLa Cells ; Humans ; NF-kappa B/antagonists & inhibitors/*metabolism ; Protein Transport/drug effects ; RNA, Small Interfering/genetics ; Signal Transduction ; TNF-Related Apoptosis-Inducing Ligand/*physiology ; Up-Regulation/drug effects