• BMB Reports
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• v.32 no.5
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• pp.419-428
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• 1999

Tumor necrosis factor (TNF) receptor members have unique structures composed of 2-4 cysteine - rich pseudorepeats in the extracellular domain. On ligation by trimeric ligand molecules, oligomerization of three receptor molecules occurs, which in turn activates the receptor and recruits intracellular signaling molecules to the cytoplasmic tail to initiate biological events. Recently, the numbers of tumor necrosis factor receptor and ligand family members have been rapidly expanding. Functional characterization of the new members has indicated redundant roles with other known members as well as provided insights into novel functions. In particular, identification of soluble decoy receptors which have the ability to bind multiple ligands highlights a complex control mechanism of immune responses by these molecules. Studies of the new members have also revealed that the TNF receptor and ligand family members play an important role in other than the immune system.

• Reproductive and Developmental Biology
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• v.29 no.2
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• pp.101-108
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• 2005

Tumor necrosis factor-related apoptosis inducing ligand (TRAIL) is a well-known inducer of apoptotic cell death in many tumor cells. 1RAIL is expressed in human placenta, and cytotrophoblast cells express 1RAIL receptors. However, the role of TRAIL in human placentas and cytotrophoblast cells is not. well understood. In this study a trophoblast cell line, JEG-3, was used as a model system to examine the effect of TRAIL. on key intracellular signaling pathways involved in the control of trophoblastic cell apoptosis and survival JEG-3 cells expressed receptors for 1RAIL, death receptor (DR) 4, DR5, decoy receptor (OcR) 1 and DeR2. Recombinant human TRAIL (rhTRAIL) did not have a cytotoxic effect determined by MIT assay and did not induce apoptotic cell death determined by poly-(ADP-ribose) polymerase cleavage assay. rhTRAIL induced a rapid and transient nuclear translocation of nuclear $factor-{\kappa}B(NF-{\kappa}B)$ determined by immunoblotting using nuclear protein extracts. rhTRAIL rapidly activated extracellular signal-regulated protein kinase (ERK) 1/2 as determined by immnoblotting for phospho-ERK1/2. However, c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (p38MAPK) and Akt (protein kinase B) were not activated by rhTRAIL. The ability of 1RAIL to induce $NF-{\kappa}B$ and ERK1/2 suggests that interaction between TRAIL and its receptors may play an important role in trophoblast cell function during pregnancy.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.53-59
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• 2023

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has no effect on normal cells, but selectively can induce apoptosis in tumor cells. Gartanin, a xanthone compound in mangosteen, has been shown to inhibit cancer cell growth by arresting the cell cycle and inducing autophage. In this study, we revealed that gartanin can sensitize TRAIL-induced human liver cancer cell death. We also found that gartanin enhances DR5 expression, a death receptor for TRAIL. This effect appears to be related to CHOP activation associated with the response of endoplasmic reticulum stress. Gartanin treatment also inhibited p62 protein expression and cleaved LC3 to activate autophagy flux, which is related with TRAIL-induced cell death. Pretreatment with autophagy flux inhibitor, LY294002, inhibited gartanin-induced DR5 expression. In summary, our results reveal that the combined treatment of gartanin and TRAIL can be a valuable tool for cancer treatment.

• Journal of Life Science
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• v.21 no.11
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• pp.1641-1651
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• 2011

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL/Apo2L) is a recently identified member of the TNF ligand family that can initiate apoptosis through the activation of their death receptors. TRAIL has been paid attention as a potential anti-cancer drug, because it selectively induces apoptosis in tumor cells in vitro and in vivo but not in most normal cells. However, recent studies have shown that some cancer cells including malignant renal cell carcinoma and hepatocellular carcinoma, are resistant to the apoptotic effects of TRAIL. Therefore, single treatment with TRAIL may not be sufficient for the treatment of various malignant tumor cells. Understanding the molecular mechanisms of TRAIL resistance and identification of sensitizers capable of overcoming TRAIL resistance in cancer cells is needed for the establishment of more effective TRAIL-based cancer therapies. Chemotherapeutic drugs induce apoptosis and the upregulation of death receptors or activation of intracellular signaling pathways of TRAIL. Numerous chemotherapeutic drugs have been shown to sensitize tumor cells to TRAIL-mediated apoptosis. In this study, we summarize biological agents and drugs that sensitize tumors to TRAIL-mediated apoptosis and discuss the potential molecular basis for their sensitization.

• BMB Reports
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• v.49 no.3
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• pp.159-166
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• 2016

Several members of tumor necrosis factor receptor (TNFR) superfamily that these members activate caspase-8 from death-inducing signaling complex (DISC) in TNF ligand-receptor signal transduction have been identified. In the extrinsic pathway, apoptotic signal transduction is induced in death domain (DD) superfamily; it consists of a hexahelical bundle that contains 80 amino acids. The DD superfamily includes about 100 members that belong to four subfamilies: death domain (DD), caspase recruitment domain (CARD), pyrin domain (PYD), and death effector domain (DED). This superfamily contains key building blocks: with these blocks, multimeric complexes are formed through homotypic interactions. Furthermore, each DD-binding event occurs exclusively. The DD superfamily regulates the balance between death and survival of cells. In this study, the structures, functions, and unique features of DD superfamily members are compared with their complexes. By elucidating structural insights of DD superfamily members, we investigate the interaction mechanisms of DD domains; these domains are involved in TNF ligand-receptor signaling. These DD superfamily members play a pivotal role in the development of more specific treatments of cancer.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.5
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• pp.513-523
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• 2018

The tumor microenvironment greatly influences cancer cell characteristics, and acidic extracellular pH has been implicated as an essential factor in tumor malignancy and the induction of drug resistance. Here, we examined the characteristics of gastric carcinoma (GC) cells under conditions of extracellular acidity and attempted to identify a means of enhancing treatment efficacy. Acidic conditions caused several changes in GC cells adversely affecting chemotherapeutic treatment. Extracellular acidity did inhibit GC cell growth by inducing cell cycle arrest, but did not induce cell death at pH values down to 6.2, which was consistent with down-regulated cyclin D1 and up-regulated p21 mRNA expression. Additionally, an acidic environment altered the expression of atg5, HSPA1B, collagen XIII, collagen XXAI, slug, snail, and zeb1 genes which are related to regulation of cell resistance to cytotoxicity and malignancy, and as expected, resulted in increased resistance of cells to multiple chemotherapeutic drugs including etoposide, doxorubicin, daunorubicin, cisplatin, oxaliplatin and 5-FU. Interestingly, however, acidic environment dramatically sensitized GC cells to apoptosis induced by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). Consistently, the acidity at pH 6.5 increased mRNA levels of DR4 and DR5 genes, and also elevated protein expression of both death receptors as detected by immunoblotting. Gene silencing analysis showed that of these two receptors, the major role in this effect was played by DR5. Therefore, these results suggest that extracellular acidity can sensitize TRAIL-mediated apoptosis at least partially via DR5 in GCs while it confers resistance to various type of chemotherapeutic drugs.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.18
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• pp.8533-8539
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• 2016

Background: B-cell chronic lymphocytic leukemia B (B-CLL), the most common type of leukemia, may be caused by apoptosis deficiency in the body. Adipose tissue-derived mesenchymal stem cells (AD-MSCs) as providers of pro-apoptotic molecules such as tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), can be considered as an effective anti-cancer therapy candidate. Therefore, in this study we assessed the role of tumor necrosis factor-producing mesenchymal stem cells oin apoptosis of B-CLL cells resistant to fludarabine-based chemotherapy. Materials and Methods: In this study, after isolation and culture of AD-MSCs, a lentiviral LeGO-iG2-TRAIL-GFP vector containing a gene producing the ligand pro-apoptotic with plasmid PsPAX2 and PMDG2 virus were transfected into cell-lines to generate T293HEK. Then, T293HEK cell supernatant containing the virus produced after 48 and 72 hours was collected, and these viruses were transduced to reprogram AD-MSCs. Apoptosis rates were separately studied in four groups: group 1, AD-MSCs-TRAIL; group 2, AD-MSCs-GFP; group 3, AD-MSCs; and group 4, CLL. Results: Observed apoptosis rates were: group 1, $42{\pm}1.04%$; group 2, $21{\pm}0.57%$; group 3, $19{\pm}2.6%$; and group 4, % $0.01{\pm}0.01$. The highest rate of apoptosis thus occurred ingroup 1 (transduced TRAIL encoding vector). In this group, the average medium-soluble TRAIL was 72.7pg/m and flow cytometry analysis showed a pro-apoptosis rate of $63{\pm}1.6%$, which was again higher than in other groups. Conclusions: In this study we have shown that tumor necrosis factor (TNF) secreted by AD-MSCs may play an effective role in inducing B-CLL cell apoptosis.

• CELLMED
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• v.3 no.1
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• pp.3.1-3.3
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• 2013

The receptor activator of NF-${\kappa}B$ ligand (RANKL), a member of the tumor necrosis factor ligand family, has extensive functions beyond osteoclast development. RANKL is expressed in many immune cells such as osteoblasts, osteocytes, marrow stromal cells, activated T cells, synovial cells, keratinocytes, and mammary gland epithelial cells as well as in various tissues. The ligation of RANK by RANKL promotes dendritic cells (DCs) survival through prosurvival signals and the up-regulation of the anti-apoptotic proteins Bcl-2 and Bcl-$x_L$ and plays a crucial role in DCs-mediated Th1 differentiation. Therefore, RANKL plays an important role in the regulation of DCs/T cells-mediated specific immunity. This review will briefly inform our current understanding of the role of RANKL signaling in T cells-DCs communication in the immune system.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.22
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• pp.9885-9889
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• 2014

Background: Tumor necrosis factor (TNF) related apoptosis-inducing ligand (TRAIL) is an antitumor candidate in cancer therapy. This study focused on effects of TRAIL, as a proapototic ligand that causes apoptosis, in B-CELL chronic lymphocytic leukemia cells (B-CLL). Materials and Methods: A population of HEK 293 cells was transducted by lentivirus that these achieved ability for producing the TRAIL protein and then HEK 293 cells transducted were placed in the vicinity of CLL cells. After 24 hours of co-culture, apoptosis of CLL cells was assessed by annexin V staining. Results: The amount of Apoptosis was examined separately in four groups: 293 HEK TRAIL ($16.17{\pm}1.04%$); 293 HEK GFP ($2.7{\pm}0.57%$); WT 293 HEK ($2{\pm}2.6%$); and CLL cells ($0.01{\pm}0.01%$). Among the groups studied, the maximum amount of apoptosis was in the group that the vector encoding TRAIL was transducted. In this group, the mean level of soluble TRAIL in the culture medium was 253pg/ml; also flow cytometry analyzes showed that proapotosis in this group was $32.8{\pm}1.6%$, which was higher than the other groups. Conclusions: In this study, we have demonstrated that TNF secreted from HEK 293 cells are effective in death of CLL cells.

• Archives of Pharmacal Research
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• v.22 no.5
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• pp.454-458
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• 1999

TR8 is a recently identified member of the tumor necrosis factor (TNF) receptor superfamily. TR8 seems to play important roles in bone metabolism as stimulation of this receptor with its ligand, TL8 or osteoclast differentiation factor (ODF), induced the differentiation and activation of osteoclasts. Despite its important biological functions, the biochemcial events ensuing form TR8 activation have not been revealed in detail. Most of TNF receptor family proteins provoke the activation of the NF-$textsc{k}$B transcription factor. In the present study, we examined the signaling potential of TR8 to induce NF-B activation. When overexpressed in a human embryonic kidney cell line by transient transfection, TR8 caused a strong activation of NF-$textsc{k}$B, which was further increased upon stimulation with TL8. The TR8-induced NF-B activation was abrogated by the co-expression of the TRAF6 mutnat lacking the Ring and zinc finger domains and that of the kinase-inactive mutant NIK. Taken together, our study suggests that the presence of intact TRAF6 and the kiase activity of NIK may be essential for TR8 to induce NF-$textsc{k}$B activation.