• 제목/요약/키워드: Cachexia

검색결과 63건 처리시간 0.019초

Regulation of Tumor Neceosis Factor-${\alpha}$ Receptors and Signal Transduction Pathways

  • Han, Hyung-Mee
    • Toxicological Research
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    • 제8권2호
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    • pp.343-357
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    • 1992
  • Tumor necrosis factor-${\alpha}$(TNF), a polypeptide hormone secreted primarily by activated macrophages, was originally identified on the basis of its ability to cause hemorrhagic necrosis and tumor regression in vivo. Subsequently, TNF has been shown to be an important component of the host responses to infection and cancer and may mediate the wasting syndrome known as cachexia. These systemic actions of TNF are reflected in its diverse effects on target cells in vitro. TNF initiates its diverse cellular actions by binding to specific cell surface receptors. Although TNF receptors have been identified on most of animal cells, regulation of these receptors and the mechanisms which transduce TNF receptor binding into cellular responses are not well understood. Therefore, in the present study, the mechanisms how TNF receptors are being regulated and how TNF receptor binding is being transduced into cellular responses were investigated in rat liver plasma membranes (PM) and ME-180 human cervical carcinoma cell lines. $^{125}I$-TNF bound to high ($K_d=1.51{\pm}0.35nM$)affinity receptors in rat liver PM. Solubilization of PM with 1% Triton X-100 increased both high affinity (from $0.33{\pm}0.04\;to\;1.67{\pm}0.05$ pmoles/mg protein) and low affinity (from $1.92{\pm}0.16\;to\;7.57{\pm}0.50$ pmoles/mg protein) TNF binding without affecting the affinities for TNF, suggesting the presence of a large latent pool of TNF receptors. Affinity labeling of receptors whether from PM or solubilized PM resulted in cross-linking of $^{125}I$-TNF into $M_r$ 130 kDa, 90 kDa and 66kDa complexes. Thus, the properties of the latent TNF receptors were similar to those initially accessible to TNF. To determine if exposure of latent receptors is regulated by TNF, $^{125}I$-TNF binding to control and TNF-pretreated membranes were assayed. Specific binding was increased by pretreatment with TNF (P<0.05), demonstrating that hepatic PM contains latent TNF receptors whose exposure is promoted by TNF. Homologous up-regulation of TNF receptors may, in part, be responsible for sustained hepatic responsiveness during chronic exposure to TNF. As a next step, the post-receptor events induced by TNF were examined. Although the signal transduction pathways for TNF have not been delineated clearly, the actions of many other hormones are mediated by the reversible phosphorylation of specific enzymes or target proteins. The present study demonstrated that TNF induces phosphorylation of 28 kDa protein (p28). Two dimensional soidum dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) resolved the 28kDa phosphoprotein into two isoforms having pIs of 6.2 and 6.1. The pIs and relative molecular weight of p28 were consistent with those of a previously characterized mRNA cap binding protein. mRNA cap binding proteins are a class of translation initiation factors that recognize the 7-methylguanosine cap structure found on the 5' end of eukaryotic mRNAs. In vitro, these proteins are defined by their specific elution from affinity columns composed of 7-methylguanosine 5'-triphosphate($m^7$GTP)-Sepharose. Affinity purification of mRNA cap binding proteins from control and TNF treated ME-180 cells proved that TNF rapidly stimulates phosphorylation of an mRNA cap binding protein. Phosphorylation occurred in several cell types that are important in vitro models of TNF action. The mRNA cap binding protein phosphorylated in response to TNF treatment was purifice, sequenced, and identified as the proto-oncogene product eukaryotic initiation factor-4E(eIF-4E). These data show that phosphorylation of a key component of the cellular translational machinery is a common early event in the diverse cellular actions of TNF.

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병기 III 자궁경부암의 방사선치료 결과 (Results of Radiation Therapy in Stage III Uterine Cervical Cancer)

  • 문창우;신병철;염하용;정태식;유명진
    • Radiation Oncology Journal
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    • 제13권3호
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    • pp.259-266
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    • 1995
  • Purpose : The aim of this study is to analyze the survival rate, treatment failure and complication of radiation therapy alone in stage III uterine cervical cancer. Materials and Methods : From January 1980 through December 1985, 227 patients with stage III uterine cervical cancer treated with radiation therapy at Kosin Medical Center were retrospectively studied. Among 227 patients, 72 patients($317{\%}$) were stage IIIa, and 155 patients($68.3{\%}$) were stage IIIb according to FIGO classification. Age distribution was 32-71 years (median: 62 years). Sixty nine patients($95.8{\%}$) in stage IIIa and 150 patient ($96.8{\%}$) in stage IIIb were squamous cell carcinoma. pelvic lymph node metastasis at initial diagnosis was 8 patients($11.1{\%}$) in stage IIIa and 29 patients($18.7{\%}$) in stage IIIb, Among 72 patients with stage IIIa, 36 patients ($50{\%}$) were treated with external radiation therapy alone by conventional technique (180-200 cGy/fr.) and 36 patients($50{\%}$) were treated with external radiation therapy with intracavitary radiotherapy(ICR) with $Cs^{137}$ sources, and among 155 patients with stage IIIb, 80 patients ($51.6{\%}$) were treated with external radiation therapy alone and 75 patients ($48.4{\%}$) were treated with external radiation therapy with ICR. Total radiation doses of stage IIIa and IIIb were 65-105 Gy(median: 78.5 Gy) and 65-125.5 Gy (median 83.5 Gy). Survival rate was calculated by life-table method. Results : Complete response rates were $58.3{\%}$(42 patients) in stage IIIa and $56.1{\%}$(87 patients) in stage IIIb. Overall 5 year survival rates were $57{\%}$ in stage IIIa and $40{\%}$ in stage IIIb. Five year survival rates by radiation technique in stage IIIa and IIIb were $64{\%},\;40{\%}$ in the group treated in combination of external radiation and ICR, and $50\%,\;40\%$ in the group of external radiation therapy alone(P=NS). Five year survival rates by response of radiation therapy in stage IIIa and IIIb were $90\%,\;66\%$ in responder group and $10\%,\;7\%$ in non-responder group (P<0.001) There were statistically no significant differences of 5 year survival rate by total radiation doses and external radiation doses(40 Gy vs 50 Gy) of whole or true pelvis in stage IIIa and IIIb(P=NS). Treatment failures rates were $40.3\%$(29 patients) in stage IIla and $57.4\%$(89 patients) in stage IIIb. 17 patients ($23.6\%$) in stage IIIa and 46 patients ($29.7\%$) in stage IIIb experienced complications. Total radiation doses more than 85 Gy produced serious complication in both stage IIIa($50\%$) and IIIb($50\%$). Serious complication rates were higher in group received external radiation doses of 50 Gy than 40 Gy to whole or true pelvis in stage IIIa and IIIb. Serious rectal complication developed in rectal doses more than 65 Gy, and serious bladder complication developed in bladder doses more than 75 Gy. Major cause of death was cachexia due to locoregional failure in both stage IIIa($34.7\%$) and IIIb($43.9\%$). Conclusion : From this study, we found that external radiation therapy with ICR was found to have a tendency to be superior to external radiation therapy alone in survival rate, local control rate and complication rate but not different in statistics, and external radiation doses of 50 Gy than 40 Gy to whole or true pelvis produced serious rectal and bladder complications in stage III uterine cervical cancer.

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말초혈액의 림프구감소증을 동반한 중증폐결핵 환자들에서 골수 내의 림프구 분획과 사이토카인 소견 (Lymphocyte Proportion and Cytokines from the Bone Marrow of Patients with Far-Advanced Pulmonary Tuberculosis with Peripheral Lymphocytopenia)

  • 안창혁;경선영;임영희;박계영;박정웅;정성환;안정열
    • Tuberculosis and Respiratory Diseases
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    • 제55권5호
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    • pp.449-458
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    • 2003
  • 연구배경 : 말초혈액에서 림프구감소증이 있거나(< $1,000/mm^3$) $T_4$-세포의 수가 $500/mm^3$ 이하인 경우, 중증폐결핵의 좋지 않은 예후를 나타내는 것으로 알려져 있다. 하지만 중증폐결핵에서 어떠한 기전으로 말초혈액의 림프구감소증이 발생되는 지는 아직 알려진 바 없다. 이에 연구자들은 말초혈액의 림프구감소증이 골수에서 림프구의 생성 및 분화 또는 순환 중에서 어떠한 단계의 이상으로 발생하는지 알아보고자 골수 소견을 관찰해 보았다. 방 법 : 1999년 8월부터 2002년 8월 사이에 가천의대 길병원에 내원한 중증폐결핵 환자들을 대상으로 하였다(FAPTB군). 65세 이상의 환자, 전신 상태가 안좋은 환자나 쇼크, 혈액학적 질환이 있는 환자는 대상에서 제외하였다. 대조군은 골수침범이나 골수에 영향을 미치지 않는 질환자들을 대상으로 하였다. 각군에서 말초혈액과 골수의 세포 분획을 분석하였고, 골수에서 IL-2, IL-7, IL-l0, TNF-${\alpha}$, IFN-${\gamma}$, TGF-${\beta}$를 측정하였다. 결 과 : 총 13명의 환자가 대상이 되었으며(M:F=9:4) 평균 연령은 $42{\pm}12$ 세였다 말초혈액에서 림프구 분획과 수는 FAPTB 군에서 의미 있게 감소되었다($7.4{\pm}3.0%$, $694{\pm}255/mm^3$ vs. $17.5{\pm}5.8%$, $1,377{\pm}436/mm^3$, 각각 p:0.0001, 0.002). 골수에서의 림프구 분획은 FAPTB군이 대조군 보다 적은 경향을 보였으나 통계적 의미는 관찰되지 않았다($9{\pm}4%$ vs. $12{\pm}3%$, p:0.l38). 골수의 IL-2 농도는 FAPTB군에서 의미 있게 낮게 관찰되었고($26.0{\pm}29.1$ vs. $112.2{\pm}42.4pg/mL$, p:0.001). IL-10도 FAPTB군에서 의미 있게 낮았다($3.4{\pm}4.7$ vs. $12.0{\pm}8.0pg/mL$, p:0.031. IL-7, TNF-${\alpha}$, IFN-${\gamma}$, TGF-${\beta}$ 농도는 두 군간에 의미 있는 차이를 보이지 않았다. 결 론 : 이상의 결과로 진행성 폐결핵 환자에서 말초혈액의 림프구감소증은 골수에서의 이상 소견과 연관이 있으리라고 추정되며, 이에는 IL-2와 IL-10이 관련되어 있을 것으로 생각되나, 향후 립프구감소증 기전의 연구가 더 필요하리라 사료된다.