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International Journal of Clinical Oncology - The practice of cancer diagnosis disclosure to children has been changed with the times. The regulations of clinical trials in the 2000s might change...  相似文献   
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To identify the role in periodontal inflammatory diseases of human gingival fibroblasts (HGF), the major constituents of gingival tissue, the expression of CD14, a possible lipopolysaccharide (LPS) receptor, and the release of soluble CD14 (sCD14) by HGF were examined. Among the HGF samples from the nine donors tested, more than 50% of the HGF from five donors expressed CD14 but less than 20% of HGF from the other four donors did so, as determined by flow cytometric analysis. The CD14 expression on the cell surface was correlated with the expression of CD14 mRNA. The HGF and skin and lung fibroblasts tested expressed no CD18, which indicates that fibroblasts do not possess other LPS receptors, such as CD11b/CD18 and CD11c/CD18. The CD14 expression by the HGF was decreased after subculturing and was highest at the confluent stage of culture. The treatment of high-CD14-expressing (CD14high) HGF with phosphatidylinositol-phospholipase C reduced CD14 expression; this result and the increase in a 55-kDa CD14 indicate that the membrane CD14 (mCD14) on the HGF may be a 55-kDa glycosylphosphatidylinositol-anchored protein. CD14high HGF spontaneously released 48- and 57-kDa sCD14. The total release of sCD14 by the HGF was augmented by gamma interferon and Escherichia coli LPS in accordance with the increased expression of mCD14. The CD14high HGF secreted interleukin-8 in response to LPS, and the secretion was completely inhibited by anti-CD14 antibody. These results suggest that (i) HGF consist of populations that are heterogeneous on the basis of different levels of expression of CD14 and (ii) CD14high HGF secrete inflammatory cytokines in response to LPS via CD14.  相似文献   
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Apoptosis induced by docetaxel that interferes with microtubule polymerization dynamics and is used clinically to treat advanced cancers, has not been fully defined in squamous cell carcinoma. In this study, apoptotic events involved in docetaxel treatment were investigated. When the human oral squamous cell carcinoma cell line HSC-3 was exposed to docetaxel for 72 h, a dose-dependent effect was observed in apoptosis using the TUNEL method. We observed activation of caspase cascade including activities like caspase-3, -8, and -9. And the pan-caspase inhibitor z-VAD-fmk prevented apoptosis induced by docetaxel (0.1 microM), showing participation of caspases in this process. Since an antagonistic CD95-antibody (ZB4) exerted no effect on docetaxel-induced apoptosis, CD95/CD95L interaction was not involved in this pathway. The caspase-8-like activity was inhibited not only by IETD-fmk (caspase-8) but also by DEVD-fmk (caspase-3). The results indicate that the caspase-8-like activation occurred downstream of DEVDase. Docetaxel promoted the formation of reactive oxygen species (ROS) in mitochondria, and preincubation of cells with anti-oxidants such as N-acetyl cysteine and pyrrolidine dithiocarbamate, protected against apoptosis mediated by docetaxel. Furthermore, treatment with docetaxel elicited reduction of mitochondrial membrane potential, and release of cytochrome c to cytosol, after 48 h of treatment. We observed binding activity to NF-kappaB consensus site and interference with the mitochondrial function via NF-kappaB after docetaxel treatment. Preventing pro-apoptotic property of NF-kappaB inhibited docetaxel-induced apoptosis. Thus, these results suggest that, following the activation of NF-kappaB by docetaxel, apoptosis is elicited through a mitochondria-dependent pathway.  相似文献   
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One of the mechanisms repressing apoptosis in tumor cells can involve the expression of anti-apoptotic NF-kappaB target genes. In this study, we demonstrated that a potent NF-kappaB inhibitor, Nalpha-tosyl-L-lysinyl chloromethyl ketone (TLCK), inhibits apoptosis of THP-1 cells triggered by etoposide (VP16), and actinomycin D (ACT D) or cycloheximide inhibits apoptosis. However, persistent activation of NF-kappaB by lipopolysaccharide (LPS) led to the survival of leukemic cells against VP16-induced apoptosis. Thus, the molecular events (Bax/X-chromosome-linked IAP (XIAP)) occurring downstream of NF-kappaB activation during VP16 and/or LPS stimulation may become important to understand the multiple effects of NF-kappaB.  相似文献   
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In the present study, the precise mechanism of the enhancing action of histone deacetylase (HDAC) inhibitors on cisplatin (CDDP)-induced apoptosis was investigated using suberoylanilide hydroxamic acid (SAHA) in human oral squamous cell carcinoma cells (HSC-3). HDAC inhibitors are promising novel compounds for the treatment of cancer, which cooperate with chemotherapeutic agents to induce apoptosis. Apoptosis enhancement of HSC-3 cells by SAHA was accompanied by the activation of caspase-3, -8 and -9, suggesting a mitochondrial-dependent amplification loop. Concomitant treatment (CDDP/SAHA) of cells resulted in the most effective enhancement of apoptosis compared to other timing combinations. By means of cell-cycle synchronization, G0/G1-phase cells proved to be a more sensitive fraction to SAHA action than their synchronized counterparts in other phases. Furthermore, cells treated with SAHA revealed a decrease in intracellular reduced glutathione (GSH) contents. Of importance, the GSH synthesis inhibitor, diethyl maleate, decreased intracellular GSH and enhanced CDDP-induced apoptosis in a similar pattern of timing to SAHA. Thus, SAHA appears to disrupt the intracellular redox balance, which causes maximal apoptosis at the G0/G1 phase arrested by CDDP in HSC-3 cells. These results demonstrate that HDAC inhibitors not only cause a change in the histone acetylation status, but are also able to influence the apoptotic process at several levels, and GSH plays a key role in governing SAHA-dependent enhancement of CDDP-induced apoptosis.  相似文献   
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The strong association of acute guttate psoriasis and streptococcal throat infection, together with the preferential use of T cells expressing a particular T-cell receptor, has suggested a role for bacterial superantigens in the pathogenesis of psoriasis. We examined the proliferative responses of peripheral blood lymphocytes (PBLs), obtained from patients with psoriasis and from healthy controls, to streptococcal superantigens, cytoplasmic membrane-associated protein (CAP) and secretion-type CAP (SCAP), isolated from group A, β-haemolytic streptococci. PBLs from patients with psoriasis showed significantly less response to SCAP and CAP than those from healthy controls. Because there was no difference between psoriatic patients and controls in the proliferative response of PBLs to staphylococcal enterotoxin A or E (SEA, SEE) or the mitogen phytohaemagglutinin (PHA), these findings strongly suggest that the reduced reactivity to the streptococcal superantigens seems to reflect anergy of a population of PBLs to the superantigens. As the CAP used in the present study stimulates Vβ8 T cells selectively, we further examined the proliferation of Vβ8 T cells after such stimulation using flow cytometry. Vβ8 T cells obtained from three of four psoriatic patients failed to proliferate in the presence of CAP, whereas they proliferated vigorously in the presence of SEE, which activates Vβ8 T cells, confirming the specific hyporesponsiveness of PBLs from psoriatic patients to streptococcal superantigens. We then determined the effects of serum factors on the suppressed response of PBLs to the streptococcal superantigens with SCAP or CAP. It was partially restored when PBLs were cultured with sera obtained from healthy subjects, although the responses were still significantly lower than those of the healthy controls. In contrast, psoriatic sera markedly suppressed the proliferative response of PBLs from healthy controls to CAP or SCAP, but showed no suppression of the proliferative response of PBLs to SEA. Because these findings suggest the presence of specific inhibitory factors in psoriatic sera, we examined whether the inhibitory effect was caused by antisuperantigen antibody. However, no significant increase was detected in antibody titre to CAP in psoriatic sera, as has been noted in sera from patients with poststreptococcal glomerulonephritis. The present results show for the first time the hyporesponsiveness of PBLs to streptococcal superantigens and the presence of serum inhibitors that specifically inhibit T-cell response to the superantigens in psoriatic patients. These findings suggest a pathological role for streptococcal infections in the pathogenesis of psoriasis.  相似文献   
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T cell receptor (TcR)gamma delta cells are known to be a minor population of T lymphocytes in the blood (less than 10%) and other peripheral lymphoid organs in healthy donors. We demonstrated here that a large proportion of TcR gamma delta cells, i.e., up to 30% of mononuclear cells (MNC) were detectable in the liver, but not other lymphoid organs of cancer patients. More importantly, the majority of such TcR gamma delta cells (greater than 70%) were shown to be lymphoblastic by electron microscopy. An activation marker of T lymphocytes, Leu-19 (CD56) was also highly expressed on the hepatic TcR gamma delta cells. The possibility of hepatic TcR gamma delta cells being activated was further examined in mice. C3H/He mice injected with syngeneic tumor cells were demonstrated to have an increased number of liver MNC; such MNC showed an ability to proliferate in vitro. These mice eventually had a considerable proportion of TcR gamma delta cells in the liver, showing activation markers, the Ia and LFA-1 antigens. These results suggest that the liver may be an important organ for activation and probably expansion of TcR gamma delta cells especially in tumor bearing hosts.  相似文献   
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TCR gamma delta + cells proliferated when MNC were stimulated with various heat-killed bacteria. We investigated here the culture conditions for their maximum proliferation. MNC were cultured for 6 days with Streptococcus pyogenes, and for 3 days with T cell mitogens, PHA and anti-CD3 mAb, in medium supplemented with various concentrations (0.05-50%) of human sera. TCR gamma delta + and TCR gamma delta- CD2+3- double negative cells induced by Str. pyogenes required high concentrations of sera (greater than 6%) for their proliferation. Moreover, increased sera (up to 50%) greatly augmented their proliferation. On the other hand, TCR alpha beta + cell proliferation induced by T cell mitogens was supported by a small concentration (even 0.1%) of the sera, and the addition of high concentrations of sera (greater than 6%) somewhat suppressed responses. Similar serum requirement patterns were evident for the induction of cytotoxic cells. These results clearly demonstrated the existence of an appropriate culture condition for the proliferation of TCR gamma delta + cells induced in vitro.  相似文献   
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