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81.
Interleukin-6 (IL-6) protects multiple myeloma cells against apoptosis induced by glucocorticoids. Here, we investigated whether inhibition of the IL-6 signaling pathway by the IL-6 receptor superantagonist Sant7 enhances the in vivo antitumor effects of dexamethasone on the IL-6-dependent multiple myeloma cell line INA-6. For this purpose, we used a novel murine model of human multiple myeloma in which IL-6-dependent INA-6 multiple myeloma cells were directly injected into human bone marrow implants in severe combined immunodeficient (SCID) mice (SCID-hu). The effect of in vivo drug treatments on multiple myeloma cell growth was monitored by serial determinations of serum levels of soluble IL-6 receptor (shuIL-6R), which is released by INA-6 cells and served as a marker of tumor growth. In SCID-hu mice engrafted with INA-6 cells, treatment with either Sant7 or dexamethasone alone did not induce significant reduction in serum shuIL-6R levels. In contrast, the combination of Sant7 with dexamethasone resulted in a synergistic reduction in serum shuIL-6R levels after 6 consecutive days of treatment. Gene expression profiling of INA-6 cells showed down-regulation of proliferation/maintenance and cell cycle control genes, as well as up-regulation of apoptotic genes in multiple myeloma cells triggered by Sant7 and dexamethasone combination. In vitro colony assays showed inhibition of myeloid and erythroid colonies from normal human CD34(+) progenitors in response to dexamethasone, whereas Sant7 neither inhibited colony growth nor potentiated the inhibitory effect of dexamethasone. Taken together, these results indicate that inhibition of IL-6 signaling by Sant7 significantly potentiates the therapeutic action of dexamethasone against multiple myeloma cells, providing the preclinical rationale for clinical trials of Sant7 in combination with dexamethasone to improve patient outcome in multiple myeloma.  相似文献   
82.
PURPOSE: To determine the prevalence and the prognostic value of microtubule component expression in tumors of patients with locally advanced or metastatic non-small cell lung cancer (NSCLC). EXPERIMENTAL DESIGN: Expression of microtubular components was immunohistochemically examined in 93 tumor samples from untreated patients with stage III and IV NSCLC. All patients received vinorelbine-based chemotherapy. Response to chemotherapy, progression-free survival, and overall survival were correlated with the expression of microtubule proteins. RESULTS: The response rate was 27.3% (21 partial responses among 77 valuable patients). Although expression of microtubule components was not associated with the response rate, high class III beta-tubulin expression was correlated with resistance to vinorelbine, defined as disease progression under treatment. Patients whose tumors expressed high levels of class III beta-tubulin isotype had shorter progression-free survival and overall survival (P = 0.002 and 0.001, respectively). High Delta2 alpha-tubulin expression was associated with a shorter overall survival (P = 0.018). Tubulin II levels were not found to be correlated with patient outcome. A multivariate analysis, taking into account sex, age, histology, stage, weight loss, and class II beta-tubulin, class III beta-tubulin, and Delta2 alpha-tubulin levels, confirmed that class III beta-tubulin expression was independently correlated with progression-free survival (P = 0.04) and overall survival (P = 0.012). CONCLUSIONS: These findings suggest that a high level of expression of class III beta-tubulin in tumor cells is associated with resistance to vinorelbine and a poor prognosis in patients with NSCLC receiving vinorelbine-based chemotherapy.  相似文献   
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PURPOSE: The purpose of this study was to investigate the safety and tolerability of MS209, a potent inhibitor of P-glycoprotein, when given in combination with docetaxel and to determine whether MS209 affects docetaxel pharmacokinetics. EXPERIMENTAL DESIGN: Patients with advanced solid malignancies were eligible for this phase I trial. Docetaxel as 1-hour infusion was given alone during the first cycle. MS209 was introduced as of cycle 2 and given orally 30 minutes after docetaxel infusion. The dose escalation scheme followed a modified Fibonacci model with six steps (docetaxel, 60-100 mg/m2 and MS209, 300-1,200 mg per body). RESULTS: A total of 30 patients were treated at five dose levels. Dose-limiting toxicities were febrile neutropenia, infection, stomatitis, dysphagia, and fatigue. The maximum tolerated dose was reached at level 5 (docetaxel, 80-MS: 1,200). Pharmacokinetic analysis failed to show a strong pharmacokinetic interaction between the two compounds, but at the highest dose levels, there is a trend to an increase of docetaxel AUC when this agent is given in combination with MS209. CONCLUSION: MS209 can be given in combination with docetaxel, with limited effect on docetaxel toxicity or pharmacokinetics.  相似文献   
85.
Serum beta2-microglobulin, the light chain of the HLA class I molecular complex, remains one of the best survival prognostic factors in multiple myeloma, but other HLA class I molecules might be of interest in monoclonal gammopathies. In this study, we evaluate total soluble HLA class I (HLA-Is) and soluble HLA-G (HLA-Gs) in 103 patients with newly diagnosed multiple myeloma, 30 patients with monoclonal gammopathy of undetermined significance (MGUS), and 30 healthy subjects, studying their prognostic value in multiple myeloma. In multiple myeloma patients, HLA-Is and HLA-Gs median values were 0.8 microg/mL and 28 ng/mL, respectively. Median HLA-Is concentration was higher in stage II and III multiple myeloma patients than in stage I multiple myeloma, MGUS, and control patients. Median HLA-Gs was significantly lower in healthy controls than in MGUS and multiple myeloma patients. A high level of HLA-Is (> or =2.1 microg/mL) was predictive of short survival (P = 0.017). For each given level of beta2-microglobulin, the relative risk of death was higher for patients with HLA-Is > or = 2.1 microg/mL than in patients with a lower level (P = 0.047). HLA-Gs, a marker of monoclonal gammopathy, was of no prognostic value, but the addition of HLA-Is to beta2-microglobulin produced an efficient prognostic score (P < 0.0001). HLA-Is is a new marker of multiple myeloma tumor load and provides additional survival prognostic information to beta2-microglobulin.  相似文献   
86.
P-glycoprotein (P-gp) is an ATP-dependent efflux membrane transporter involved in many drug pharmacokinetics in humans. Decreasing its expression could enhance the bioavailability of substrates as digoxin. We have recently found that human recombinant interleukin-2 (rIL2) in vivo decreases P-gp expression in intestine and brain of mice and modifies oral digoxin pharmacokinetics. The aim of the study was to evaluate the involvement of bioavailability in the rIL2 pretreatment effect on digoxin pharmacokinetics by comparing oral and i.v. digoxin pharmacokinetics before and after rIL2 pretreatment (10 microg/kg). We also tried to show the possible effect of a low rIL2 dose (1 microg/kg) pretreatment on oral digoxin pharmacokinetics. First, adult Swiss mice received a single oral or i.v. dose of digoxin (0.03 mg/kg). Two weeks later, the same animals were treated by rIL2 i.p. twice a day (10 microg/kg) for 4 days and received digoxin again at day 5. As well, another group received oral digoxin (0.03 mg/kg) with a 1 microg/kg rIL2 pretreatment. Blood was collected after digoxin administration with and without rIL2 pretreatment. Digoxin pharmacokinetics were described by a one-compartment model. The 10 microg/kg rIL2 pretreatment did not modify i.v. digoxin pharmacokinetics, whereas oral digoxin pharmacokinetics were significantly modified by the 10 microg/kg rIL2 pretreatment and not by the 1 microg/kg rIL2 pretreatment. The decrease of P-gp activity, caused by rIL2 (10 microg/kg), increased digoxin bioavailability. An increase in exposure and intracellular level of drugs is expected from rIL2 pretreatment.  相似文献   
87.
观察利用微信干预增加青光眼患者体力活动的效果。方法:前瞻性随机对照研究。选择2018年 6-12月于温州医科大学附属眼视光医院门诊确诊的青光眼患者102例作为研究对象。利用Excel生成的随机数随机分为对照组和干预组。对照组患者仅在门诊入组时进行运动宣教,并告知其可增加每天的运动步数;干预组患者入组时进行运动宣教,告知其可增加每天的运动步数的同时,加入微信群进行运动提醒干预。所有患者均需利用运动监测仪器完成基线1周和随访1个月的体力活动监测。采用卡方检验、独立样本t检验、Mann-Whitney U检验、配对t检验及Wilcoxon符号秩检验进行数据分析。结果:排除30例基线运动量较大(步数>12 000步/d)、依从性不好及其他原因失访的患者,最终纳入72例(对照组42例,干预组30例)。干预组患者干预后的步数(t=4.94,P<0.001),运动消耗的卡路里(Z=-2.87,P=0.004),代谢当量(Z=-3.30,P=0.001),中等强度体力活动时间(Z=-2.89, P=0.004),高强度体力活动时间(t=2.57,P=0.016)及中高强度体力活动时间(Z=-3.01,P=0.003)均较基线增加;轻度体力活动时间(t=-2.14,P=0.041)和久坐静止不动次数较干预前减少(t=-2.76, P=0.022)。对照组随访的步数也较基线增加(t=3.29,P<0.001),轻度体力活动时间较基线减少(t=-2.57,P=0.014)。另外,干预组的高强度体力活动时间增加量(随访-基线)(Z=-3.04,P=0.002)和超高强度体力活动时间增加量(Z=-2.06,P=0.040)明显高于对照组,差异均有统计学意义。结论:微信干预可以增加青光眼患者的每天运动步数和中高强度体力活动时间,减少患者的轻度体力活动时间和久坐静止次数。  相似文献   
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There is controversy over the role of Her-2 in osteosarcoma, with some investigators reporting association between expression and adverse outcome, whereas others point to the lack of gene amplification and membranous expression by immunohistochemistry (IHC) as inconsistent with biological significance. Her-2 normally requires pairing with epidermal growth factor receptor (EGFR), Her-3, or Her-4, but these have been less well studied in osteosarcoma. We evaluated the expression of each of these receptors in osteosarcoma and their potential to contribute to pathogenesis by examining a panel of low-passage primary osteosarcoma cell lines, comparing these with archival tumor specimens. Her-2 immunoreactivity was seen frequently in the diffuse staining pattern described previously. We observed EGFR in all samples by IHC. Her-3 expression was not observed. Her-4 expression was nuclear in distribution in all tumor samples and many cell line samples, consistent with activation and cleavage of the receptor. Quantified expression of Her-2 and EGFR mRNA by quantitative, real-time PCR in cell lines correlated with IHC for Her-2 but not for EGFR. Western blot identified full-length receptors for EGFR and Her-2 in all expected cell lines and showed Her-4 to be predominantly in the p80 form. Flow cytometry identified cell surface Her-2 and EGFR in all lines with receptor expression by IHC. We conclude that the cell surface expression of Her-2 and EGFR and the nuclear localization of the activated p80 fragment of Her-4 suggest that all three may be contributing to osteosarcoma pathogenesis. Therapy directed against this family of receptors may be beneficial for patients with osteosarcoma.  相似文献   
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