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Despite improvements in detection, surgical approaches and systemic therapies, breast cancer remains typically incurable once distant metastases occur. High expression of TRAIL-R2 was found to be associated with poor prognostic parameters in breast cancer patients, suggesting an oncogenic function of this receptor. In the present study, we aimed to determine the impact of TRAIL-R2 on breast cancer metastasis. Using an osteotropic variant of MDA-MB-231 breast cancer cells, we examine the effects of TRAIL-R2 knockdown in vitro and in vivo. Strikingly, in addition to the reduced levels of the proliferation-promoting factor HMGA2 and corresponding inhibition of cell proliferation, knockdown of TRAIL-R2 increased the levels of E-Cadherin and decreased migration. In vivo, these cells were strongly impaired in their ability to form bone metastases after intracardiac injection. Evaluating possible underlying mechanisms revealed a strong downregulation of CXCR4, the receptor for the chemokine SDF-1 important for homing of cancers cells to the bone. In accordance, cell migration towards SDF-1 was significantly impaired by TRAIL-R2 knockdown. Conversely, overexpression of TRAIL-R2 upregulated CXCR4 levels and enhanced SDF-1-directed migration. We therefore postulate that inhibition of TRAIL-R2 expression could represent a promising therapeutic strategy leading to an effective impairment of breast cancer cell capability to form skeletal metastases.  相似文献   
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We analysed whether the factor V Leiden mutation--the most common hereditary predisposing factor for venous thrombosis--is associated with early and long-term graft dysfunction after kidney transplantation in 394 Caucasian kidney transplant recipients. The presence of factor V Leiden mutation was identified by allele specific PCR. The prevalence of the factor V Leiden mutation was compared to 32216 unselected neonates. The prevalence of the factor V Leiden mutation (GA genotype) was similar in 394 kidney transplant recipients and 32216 neonates. The frequency of known factors predicting long-term graft function were similar in patients with the GA genotype and with the normal factor V gene (GG genotype). The GA genotype was associated with the occurrence of no primary graft function (risk: 2.87: 95% confidence interval: 1.01-8.26; p < 0.05), the number of dialysis after transplantation in patients with no primary graft function until graft function (7.5 +/- 2.06 dialysis in GA patients; 4.2 +/- 0.36 dialyses in GG patients; p < 0.05), and the risk for at least one acute rejection episode (risk: 3.83; 95% confidence interval: 1.38-10.59; p < 0.02). The slope of l/creatinine per year was significantly lower in patients with the GA genotype (GA patients: -0.0204 +/- 0.008 dl/mg per year; GG patients: 0.0104 +/- 0.004 dl/mg per year; p < 0.02). The annual enhancement of the daily protein excretion rate was elevated in patients with the GA genotype (GA patients: 38.5 +/- 16.6 mg/24 h per year; GG patients: 4.9 +/- 4.4 mg/24 h per year; p < 0.02). Our study showed that the factor V Leiden mutation is associated with the occurrence of delayed graft function, acute rejection episodes and chronic graft dysfunction after kidney transplantation.  相似文献   
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PURPOSE: Preclinical studies suggested that the antiangiogenic agent TNP-470 was synergistic with cytotoxic therapy. TNP-470 was administered with paclitaxel to adults with solid tumors to define the safety and optimal dose of the combination regimen and to assess pharmacokinetic interactions. PATIENTS AND METHODS: Thirty-two patients were enrolled chronologically onto one of two treatment arms. Arm A involved a fixed TNP-470 dose with escalating doses of paclitaxel, and Arm B involved a fixed paclitaxel dose with escalating doses of TNP-470. Paclitaxel and TNP-470 pharmacokinetics were evaluated along with toxicity. RESULTS: The combination of TNP-470 administered at 60 mg/m(2) three times per week and paclitaxel 225 mg/m(2) administered over 3 hours every 3 weeks was defined as both the maximum-tolerated dose and the optimal dose. Myelosuppression was similar to that expected with paclitaxel alone. Mild to moderate neurocognitive impairment was observed; however, the majority of changes were subclinical and reversible as determined by prestudy and poststudy neuropsychiatric test results. A clinically insignificant decrease of paclitaxel clearance was observed for the combination. Median survival for all patients was 14.1 months. Partial responses were reported in eight (25%) of 32 patients and in six (38%) of 16 patients with NSCLC, 60% of whom had received prior chemotherapy. CONCLUSION: The combination of TNP-470 and paclitaxel, each at full single-agent dose, seems well tolerated, with minimal pharmacokinetic interaction between the two agents. Further studies of TNP-470 with chemotherapy regimens are warranted in NSCLC and other solid tumors.  相似文献   
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PURPOSE: It has recently been suggested that the diagnostic threshold for the prostate specific antigen (PSA) assay be lowered to enhance prostate cancer detection. A 22% incidence of prostate cancer has been reported in men with PSA between 2.5 and 4.0 ng/ml. We designed a study to confirm this observation. MATERIALS AND METHODS: Men who participated in our free early detection program and who had serum PSA between 2.5 and 4.0 ng/ml were asked to undergo prostate biopsy. Of 268 eligible men 151 (56%) agreed to participate in this free trial. All men underwent biopsy using an 11-core multisite directed biopsy scheme. All biopsy cores were color coded for location specificity and examined by 1 pathologist. RESULTS: Cancer was identified in 24.5% (37 of 151) of the men biopsied. The median age of men with cancer was 62 years (range 43 to 74). Conventional systematic sextant biopsies, which accounted for 6 of the 11 cores, detected 73.0% (27 of 37) of the cancers and the alternate site biopsies identified the remaining 10. Gleason score was 6 in 25 men, 3 + 4 in 5, 4 + 3 in 4 and 8 or greater in 3 (median Gleason score 6). There were 14 men who had 1 core positive for cancer, 9 had 2 and 14 had more than 2 (median number of positive cores 2). Of the 14 men with 1 positive core 11 had a less than 3 mm focus of cancer and 8 had only a positive alternate site biopsy. There were 11 cases of abnormal results on digital rectal examination, 5 of which were cancer, and 31 cases of abnormal results on ultrasonography, 13 of which were cancer. Median biological variability in PSA was +/-15% (range 0.4% to 440.0%). CONCLUSIONS: We found a significant incidence of cancer (24.5%, 37 of 51) in men with serum PSA between 2.5 and 4.0 ng/ml. In our study 67.6% of the detected cancers were significant based on the biopsy data. If the PSA threshold is lowered the conventional systematic sextant technique may be preferable to an extended strategy.  相似文献   
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Rare cases of tuberculosis due to Mycobacterium bovis have been described in humans who have been exposed to cattle or other infected animals. We report a case of tuberculosis in cattle exposed to a patient infected with M. bovis, where the strain isolated in the cattle and the patient were identical. As the patient is reported to have been exposed and contaminated during childhood, this seems to be the first documented case of transmission of M. bovis from animal to man and back to animal.  相似文献   
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