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941.
We examined possible anticancer effects of thiazolidinediones (TZDs) in 6074 Chinese with Type 2 diabetes free of cancer at enrolment. During a median follow-up of 4.93 years, 270 patients developed cancer. Use of TZDs was associated with reduced risk of cancer in a dose-response manner in multivariable analysis.  相似文献   
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Purpose

S100A4, a multifunctional protein, has been linked to the invasive growth and metastases of several human cancers. This study investigated the association between S100A4 and overall survival and other clinicopathological features in patients with stage C colonic cancer.

Methods

Clinical and pathological data were obtained from a prospective hospital registry of 409 patients who had a resection for stage C colonic cancer. Tissue microarrays for immunohistochemistry were constructed from archived tissue. S100A4 staining intensity and percentage of stained cells were assessed in nuclei and cytoplasm for both the central part of the tumour and at the advancing front. Overall survival was analysed by the Kaplan–Meier method and Cox regression.

Results

Only a high percentage of cells with S100A4 cytoplasmic staining in frontal tissue was associated with poor survival (hazard ratio, 1.6; 95?% CI 1.1–2.2; p?=?0.008) after adjustment for other prognostic variables. There was no association between frontal cytoplasmic S100A4 expression and any of 13 other clinicopathological variables.

Conclusions

High expression of S100A4 in cytoplasm at the advancing front of stage C colonic tumours indicates a poor prognosis. Whether S100A4 can predict response to adjuvant chemotherapy remains to be investigated in a randomised clinical trial.  相似文献   
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A novel theory in the field of tumor biology postulates that cancer growth is driven by a population of stem-like cells, called tumor-initiating cells (TICs). We previously identified a TIC population derived from hepatocellular carcinoma (HCC) that is characterized by membrane expression of CD133. Here, we describe a novel mechanism by which these cells mediate tumor growth and angiogenesis by systematic comparison of the gene expression profiles between sorted CD133 liver subpopulations through genome-wide microarray analysis. A significantly dysregulated interleukin-8 (IL-8) signaling network was identified in CD133(+) liver TICs obtained from HCC clinical samples and cell lines. IL-8 was found to be overexpressed at both the genomic and proteomic levels in CD133(+) cells isolated from HCC cell lines or clinical samples. Functional studies found enhanced IL-8 secretion in CD133(+) liver TICs to exhibit a greater ability to self-renew, induce tumor angiogenesis, and initiate tumors. In further support of these observations, IL-8 repression in CD133(+) liver TICs by knockdown or neutralizing antibody abolished these effects. Subsequent studies of the IL-8 functional network identified neurotensin (NTS) and CXCL1 to be preferentially expressed in CD133(+) liver TICs. Addition of exogenous NTS resulted in concomitant up-regulation of IL-8 and CXCL1 with simultaneous activation of p-ERK1/2 and RAF-1, both key components of the mitogen-activated protein kinase (MAPK) pathway. Enhanced IL-8 secretion by CD133(+) liver TICs can in turn activate an IL-8-dependent feedback loop that signals through the MAPK pathway. Further, in its role as a liver TIC marker CD133 also plays a functional part in regulating tumorigenesis of liver TICs by way of regulating NTS, IL-8, CXCL1, and MAPK signaling. CONCLUSION: CD133(+) liver TICs promote angiogenesis, tumorigenesis, and self-renewal through NTS-induced activation of the IL-8 signaling cascade.  相似文献   
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The new oral anticoagulants dabigatran, rivaroxaban and apixaban have advantages over warfarin which include no need for laboratory monitoring, less drug-drug interactions and less food-drug interactions. However, there is no established antidote for patients who are bleeding or require emergent surgery and there is a paucity of evidence to guide the clinical care during these situations. Members of thrombosis and anticoagulation groups participating in the Thrombosis and Hemostasis Summit of North America formulated expert opinion guidance for reversing the anticoagulant effect of the new oral anticoagulants and suggest: routine supportive care, activated charcoal if drug ingestion was within a couple of hours, and hemodialysis if feasible for dabigatran. Also, the pros and cons of the possible use of four factor prothrombin complex concentrate are discussed.  相似文献   
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