• BMB Reports
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• 제42권5호
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• pp.260-264
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• 2009

Tumor necrosis factor-$\alpha$ (TNF-$\alpha$) exhibits cytotoxicity towards various tumor cells in vitro and induces apoptotic necrosis in transplanted tumors in vivo. It also shows severe toxicity when used systemically for the treatment of cancer patients, hampering the development of TNF-$\alpha$ as a potential anticancer drug. In order to understand the structure-function relation of TNF-$\alpha$ with respect to receptor binding, we selected four regions on the bottom of the TNF-$\alpha$ trimer that are in close contact with the receptor and carried out mutagenesis studies and computational modeling. From the study, various TNF-$\alpha$ muteins with a high therapeutic index were identified. These results will provide a structural basis for the design of highly potent TNF-$\alpha$ for therapeutic purposes. By conjugating TNF-$\alpha$ muteins with a high therapeutic index to a fusion partner, which targets a marker of angiogenesis, it could be possible to develop TNF-$\alpha$ based anticancer drugs.

• Toxicological Research
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• 제11권2호
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• pp.169-173
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• 1995

The effects of tumor necrosis factor alpha $(TNF-{\alpha})$ on growth and tubular formation of bovine aortic endothelial cells were examined using an in vitro angiogenesis model system. The growth of endothelial cells was enhanced in a dose-dependent manner when the cells were cultured with $TNF-{\alpha}$ for 3 days, but $TNF-{\alpha}$, at the concentration of 1 nM or higher, produced a growth inhibition of endothelial cells when the cells were cultured for 8 days. The endothelial cells incubated with $TNF-{\alpha}$ for 48-h exhibited a typical morphologic change. Then, they showed a fibroblastoid organization of overlapping, elongated, and spindle-shaped cells. $TNF-{\alpha}$, at the concentration of O. 1 nM or higher, inhibited the tubular formation of vascular endothelial cells in an in vitro anglogenesis model using a 3-dimensional culture system.

• 생명과학회지
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• 제16권7호
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• pp.1207-1213
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• 2006

Tumor necrosis $factor-{\alpha}\;(TNF-{\alpha})$는 염증성 골질환에서의 골조직의 손실과 밀접한 관련이 있다. 본 연구에서는 인체 골수 유래 중간엽 줄기세포의 골세포로의 분화과정에 대한 $TNF-{\alpha}$의 영향을 조사하였다. $TNF-{\alpha}$는 골수 유래 중간엽 줄기세포의 골세포로의 분화를 나타내는 표시인 세포외 무기질 축적과 alkaline phosphatase의 발현의 증가를 일으켰으며 2ng/ml의 농도에서 최대의 증가를 나타내었다. $TNF-{\alpha}$에 의한 골세포로의 분화는 $NF_kB$의 저해제에 의해서는 영향받지 않았으나 JNK 특이 저해제인 SP600125에 의해 완벽하게 억제되었다. 이는 $TNF-{\alpha}$에 의한 골수 유래 중간엽 줄기세포의 골세포로의 분화과정에 JNK가 중요한 역할을 한다는 것을 제시한다.

• Clinical and Experimental Reproductive Medicine
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• 제26권1호
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• pp.97-101
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• 1999

Male genital tract inflammatory conditions may be associated with unexplained infertility. The presence of cytokine such as tumor necrosis factor-alpha (TNF-${\alpha}$) was reported in the semen of infertile men. However, the effect of these cytokines on human sperm function is still unclear. The purpose of this study was to investigate the in-vitro effects of TNF-alpha on human sperm motility with computer assisted sperm analysis. Washed sperm from 16 normal men were incubated without and with TNF-${\alpha}$ (0.1, 10, 1000 ng/ml). The changes of parameters of sperm motility were recorded at different time intervals (0, 5, 24 hour). There was no significant change of parameters of sperm motility in the incubation with TNF-${\alpha}$. It is suggested that TNF-${\alpha}$ alone does not interfere with the sperm motility and more studies are needed.

• BMB Reports
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• 제29권6호
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• pp.530-534
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• 1996

Astrocyte are the major glial cell type in the central nervous system (CNS), and analogous to macrophage, mediates the number of immune responses such as production of cytokines including tumor necrosis factor alpha ($TNF-{\alpha}$) upon activation. $TNF-{\alpha}$ has been implicated in neuroimmunological disorders through killing oligodendrocytes and thus causing demyelination. It has been previously demonstrated that mitogen-activated T cells synthesized a 26 kDa precursor form of $TNF-{\alpha}$ which is bound to the surface of a membrane, and is later secreted as a 17 kDa mature version. In order to examine whether astrocytes would produce the transmembrane form of $TNF-{\alpha}$, astrocytes were stimulated with biological stimuli and the membrane form of $TNF-{\alpha}$ was analyzed by Western blot and FACS analysis. When astrocytes are stimulated with lipopolysaccharide (LPS), $IFN-{\gamma}/LPS$, or $IFN-{\gamma}/IL-1{\beta}$, they were able to express a membrane-anchored $TNF-{\alpha}$ of approximately 26 kDa protein which was immunoreactive to an $anti-TNF-{\alpha}$ antibody, whereas unstimulated astrocytes or astrocytes treated with $IFN-{\gamma}$ or $IL-1{\beta}$ alone was not. Our FACS data were also consistent with the immunoblot analysis. Our result suggests that the membrane form of $TNF-{\alpha}$ expressed by activated astrocytes may cause local damage to oligodendrocytes by direct cell-cell contact and contribute to demyelination observed in multiple sclerosis (MS) and experimental allergic encephalomyelitis (EAE).

• Archives of Pharmacal Research
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• 제22권4호
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• pp.348-353
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• 1999

Possible antiinflammatory effect of eudesmin were examined by assessing the effects on tumor necrosis factor (TNF)-$\alpha$ production and lymphocyte proliferation as well as cytotoxicity against murine and human macrophages. the compound significantly inhibited TNF-$\alpha$, production by lipopolysaccaride (LPS)-stimulated murine macrophage RAW264.7 without displaying cytotoxicity suggesting that eudesmin may inhibit TNF-$\alpha$ production without any interference of normal cell function. It also significantly attenuated T cell proliferation stimulated by concanavalin A (Con A) in a dose-dependent manner.

• Environmental Analysis Health and Toxicology
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• 제28권
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• pp.12.1-12.5
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• 2013

Objectives The role of genetic polymorphisms of tumor necrosis factor-alpha (TNF-${\alpha}$) for lung cancer development was evaluated. Methods Genotypes of the TNF-${\alpha}$ polymorphisms, -1210C>T, -487A>G, -417A>G, IVS1+123G>A, and IVS3+51A>G, were determined in 616 lung cancer cases and 616 lung cancer-free controls. Results After adjusting for body mass index and smoking, each TNF-${\alpha}$ genotype or haplotype composed of five TNF-${\alpha}$ single nucleotide polymorphisms did not show an association with lung cancer risk (p>0.05). The statistical power was found to be 88.4%, 89.3%, 93.3%, 69.7%, and 93.9% for 1210C>T, -487A>G, -417A>G, IVS1+123G>A, and IVS3+51A>G, respectively. Furthermore, the effects of each SNP or haplotype on lung cancer risk were not found to be different according to the cell type of lung cancer (p>0.05). In the repeated analysis with only subjects without other diseases related to inflammation, there was also no association between polymorphisms or haplotypes of the TNF-${\alpha}$ gene and lung cancer risk (p>0.05). Conclusions This study found no association between common variants of the TNF-${\alpha}$ gene and lung cancer risk.

• 한국발생생물학회지:발생과생식
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• 제5권2호
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• pp.101-106
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• 2001

Insulin과 tumor necrosis factor alpha(TNF-$\alpha$)에 의한 초기 배아 발생의 조절기작을 알아보고자 생쥐의 상실배를 대상으로 이들이 첨가된 배양액에서 형태발생, 세포증식을 조사하고, 포배에서 mitogen activated protein kinase(MAPK, ERK1/2)의 활성 변화에 미치는 영향을 조사하였다. Insulin은 상실배의 체외발생 및 포배내 할구 수를 대조군에 비해 유의하게 증가시켰으며, TNF-$\alpha$는 발생율을 유의하게 감소시켰다. Insulin은 TNF- $\alpha$에 의한 배아 발생율 감소를 완화하였다. TNF-$\alpha$는 농도에 의존적으로 MAPK 활성을 감소시켰으며, insulin은 포배에서 MAPK의 활성을 유의하게 증가시킨 반면 TNF-$\alpha$는 처리농도에 의존적으로 MAPK 활성을 감소시켰다. 50 ng/ml 농도의 TNF-$\alpha$를 전처리한 포배에서는 insulin에 의한 MAPK 활성의 증가가 저해되었다. 이러한 결과로부터 생쥐의 착상전 초기 배아 발생조절에 insulin과 TNF-$\alpha$ 사이에 MAPK를 경유하는 cross talk이 존재함을 확인하였고 insulin은 TNF-$\alpha$ 에 의한 배아의 손상을 억제하는 것으로 사료된다.

• Clinical and Experimental Reproductive Medicine
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• 제36권1호
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• pp.35-43
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• 2009

목 적: 정액 내 tumor necrosis factor-alpha (TNF-${\alpha}$) 농도와 정자 DNA 손상 및 정액 검사 소견과의 관련성을 평가하고자 하였다. 연구방법: 정액 표본은 45명의 건강한 남성에서 자위에 의하여 획득하였다. 정자의 상태는 컴퓨터 정액 분석기를 이용하여 판정하였으며, 두부의 DNA 손상은 TUNEL 분석방법에 의해 측정하였다. TNF-${\alpha}$ 농도는 동결-융해된 정장액에서 ELISA법으로 측정하였다. 결 과: 정자 DNA 손상율은 1.9%에서 53% (mean ${\pm}$ SD, 12.4${\pm}$9.6%)로 매우 광범위하게 나타났다. 단변량분석에 의하면 DNA 손상 정도와 정자의 농도, 운동성과는 관련이 없었으나, 직진운동성 (linearity)과는 음의 상관 관계를 나타내었으며 (r=-0.325, p=0.03) 연구 대상 남성의 연령과는 양의 상관 관계를 나타내었다 (r=0.484, p=0.001). 정액내에 존재하는 TNF-${\alpha}$ (>1 pg/mL)는 연구 대상 남성의 73.3% (33/45)에서 검출되었으며 평균 농도는 4.9 pg/mL, 범위는 1.1에서 22.6 pg/mL이었다. 정액 검사 상의 정자 상태와 정자 DNA 손상과는 유의한 관련성이 나타나지 않았다. 결 론: 본 연구에서는 정자 DNA의 손상이 남성의 연령과 관련성이 있음을 확인하였으나, TNF-${\alpha}$와의 관련성은 확인할 수 없었다.

• Toxicological Research
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• 제13권3호
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• pp.203-208
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• 1997

The antigenic potential of M3S tumor necrosis factor-$\alpha$(M3S TNF), which is a mutated form of TNF(TNF mutein) designed to reduce adverse effects of wild type human TNF, was investigated in the present study. The antigenicity of M3S TNF was examined by conducting active systemic anaphylaxis (ASA) test in guinea pigs, heterologous(mouse-rat) passive cutaneous anaphylaxis(PCA) test and passive hemagglutination(PHA) test. The experimental animals were divided into low, medium, high and the highest dose groups and the groups with or without immunoadjuvant, sensitized according to the appropriate schedule and challenged. In ASA test, when challenged with 120 $\mu\textrm{g}$ /animal, moderate to severe positive anaphylactic responses were observed in groups sensitized with 12 $\mu\textrm{g}$ /animal, 120 $\mu\textrm{g}$ /animal and 120 $\mu\textrm{g}$ /animal+Freund's complete adjuvant. In PCA test, positive responses were observed in the group sensitized with the highest dose emulsified with an alum(12 $\mu\textrm{g}$ /animal+alum). In PHA test, positive responses were observed in the group sensitized with 3 $\mu\textrm{g}$ /animal emulsified with an alum. All the other groups in each experiment showed negative responses. Based on these results, M3S TNF is considered to have some antigenic potential.