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101.
Adiponectin is the major adipocytes-secreted protein involved in obesity-related breast cancer growth and progression. We proved that adiponectin promotes proliferation in ERα-positive breast cancer cells, through ERα transactivation and the recruitment of LKB1 as ERα-coactivator. Here, we showed that adiponectin-mediated ERα transactivation enhances E-cadherin expression. Thus, we investigated the molecular mechanism through which ERα/LKB1 complex may modulate the expression of E-cadherin, influencing tumor growth, progression and distant metastasis. We demonstrated that adiponectin increases E-cadherin expression in ERα-positive 2D and higher extent in 3D cultures. This occurs through a direct activation of E-cadherin gene promoter by ERα/LKB1-complex. The impact of E-cadherin on ERα-positive breast cancer cell proliferation comes from the evidence that in the presence of E-cadherin siRNA the proliferative effects of adiponectin is no longer noticeable. Since E-cadherin connects cell polarity and growth, we investigated if the adiponectin-enhanced E-cadherin expression could influence the localization of proteins cooperating in cell polarity, such as LKB1 and Cdc42. Surprisingly, immunofluorescence showed that, in adiponectin-treated MCF-7 cells, LKB1 and Cdc42 mostly colocalize in the nucleus, impairing their cytosolic cooperation in maintaining cell polarity. The orthotopic implantation of MCF-7 cells revealed an enhanced E-cadherin-mediated breast cancer growth induced by adiponectin. Moreover, tail vein injection of MCF-7 cells showed a higher metastatic burden in the lungs of mice receiving adiponectin-treated cells compared to control. From these findings it emerges that adiponectin treatment enhances E-cadherin expression, alters cell polarity and stimulates ERα-positive breast cancer cell growth in vitro and in vivo, sustaining higher distant metastatic burden.  相似文献   
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103.
A large number of studies have suggested that being a woman represents a potential risk factor for the development of adverse drug reactions (ADRs). The aim of this study is to further explore the differences between men and women with regard to reported ADRs, particularly those associated with psychotropic drugs. We used spontaneous reports of suspected ADRs collected by Midi‐Pyrénées (France), Veneto (Italy) and Castilla y León (Spain) Regional Pharmacovigilance Centres (January 2007–December 2009). All the reports including a psychotropic medication were selected in a first step; age distribution, seriousness and type of ADRs were compared between men and women. Reports of nonpsychotropic drugs were similarly identified and treated. The absolute number of reports and the proportion, considering population, were higher in women than in men. This was observed for all reports, but was particularly higher for psychotropic drugs (592 vs. 375; P < 0.001) than for nonpsychotropics drugs (5193 vs. 4035; P < 0.001). Antidepressants were the most reported (women, 303; men, 141; P < 0.001); the reporting rates (number of reports divided by exposed patients in the same period, estimated through sales data) for these drugs, however, were not significantly different between women (0.87 cases per 10 000 treated persons per year) and men (0.81 cases per 10 000 treated persons per year). Although there was a higher number of reports of ADRs in women, ADR reporting rates might be similar as highlighted by the case of antidepressants. Antidepressant ADRs in fact were similarly reported in men and in women. Gender differences are sometimes subtle and difficult to explore. International networks, as the one established for this study, do contribute to better analyse problems associated with medications.  相似文献   
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BackgroundThe purpose of this study was to evaluate the prognostic and predictive value of p27 expression in patients with early breast cancer.Patients and methodsQuantitative immunofluorescence assays for p27 were done on a tissue microarray that included 823 samples from patients randomized between anthracycline-based chemotherapy and no chemotherapy. Quantification of p27 was done using the AQUA® system (HistoRx, Inc., Branford, CT). Both p27 nuclear expression and the nuclear to cytoplasmic ratio were assessed.ResultsNuclear p27 expression was not predictive for the efficacy of anthracycline-based chemotherapy [adjusted P = 0.18 for disease-free survival (DFS)] nor prognostic [95% confidence interval (CI) 0.99–1.01, P = 0.49]. However, p27 nuclear/cytoplasmic ratio was predictive for the efficacy of adjuvant chemotherapy (adjusted P = 0.016 DFS). The adjusted hazard ratio (HR) for relapse associated with adjuvant chemotherapy was 0.56 (95% CI 0.37–0.84, P = 0.005) and 1.06 (95% CI 0.76–1.47, P = 0.74) for patients with high and low nuclear/cytoplasmic ratio, respectively. p27 N/C ratio was prognostic in patients treated with chemotherapy (HR for relapse or death for a 1 unit increase in p27 N/C ratio was 0.30, 95% CI 0.12–0.77) but not in the untreated arm (HR for relapse or death was 1.27, 95% CI 0.58–2.8).ConclusionsThis study did not confirm the role of p27 nuclear expression as a prognostic parameter. However, the p27 nuclear/cytoplasmic ratio was predictive in patients treated with anthracycline-based chemotherapy.  相似文献   
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107.
AIMS: Cutaneous manifestations are frequently reported in association with drug use. The aim of this study was to analyse the skin reactions reported to the spontaneous surveillance systems of four Italian regions (Friuli Venezia Giulia, Lombardy, Sicily and the Veneto), and correlate the reports with estimated drug consumption during the same period, paying particular attention to the reactions to antimicrobial agents and nonsteroidal anti-inflammatory drugs (NSAIDs). METHODS: All of the adverse drug reactions (ADRs) reported spontaneously between January 1996 and December 1997 to the surveillance systems of four Italian regions (a total population of about 20 million people) were analysed by a panel of experts including dermatologists. On the basis of the Critical Term List of the World Health Organization (WHO), the reactions were classified as either serious or nonserious events. Drug consumption was expressed as a daily defined dose (DDD)/1000 inhabitants/day. RESULTS: A total of 2224 adverse skin reaction reports (44.7% of all of the reported ADRs) were identified, making a reporting rate of about 5.5 per 100 000 inhabitants/year. The female/male ratio was 1.58, and the reporting rate progressively increased with age. The drug categories with the highest number of cutaneous reactions were antimicrobials, followed by NSAIDs, analgesics and radiology contrast media. There was a total of 372 (16.9%) serious reaction reports, the most frequent being angioedema (171 cases), erythema multiforme (68 cases) and photosensitivity (37 cases). Co-trimoxazole, followed by the cephalosporins and fluoroquinolones, were associated with the highest consumption-related reporting rate among the antimicrobials, and aspirin and dipyrone among the NSAIDs and analgesics. CONCLUSIONS: Spontaneous reports from four Italian regions revealed that the skin was the organ most frequently affected by ADRs. The paper shows the validity of a regional decentralized system in Italy.  相似文献   
108.

Aim  

The aim of the present study was to collect and compare cases of drug-induced PML in order to contribute to the debate about the role of the underlying diseases and/or drug immunosuppression in PML occurrence.  相似文献   
109.
Nitric oxide (NO) is a diatomic free radical produced from L-arginine by constitutive and inducible nitric oxide synthase (cNOS and iNOS) in numerous mammalian cells and tissues. Nitric oxide (NO), superoxide (O2-) and their reaction product peroxynitrite (ONOO-) may be generated in excess during the host response against viral and antibacterial infections and contribute to some pathogenesis by promoting oxidative stress, tissue injury and, even, cancer. Oxidative damage, caused by action of free radicals, may initiate and promote the progression of a number of chronic diseases, including cancer, cardiovascular diseases, Alzheimer's disease, diabetes and inflammation. The mechanism of inflammation injury is attributed, in part, to release of reactive oxygen species from activated neutrophils and macrophages. ROS propagate inflammation by stimulating release of mediators such as NO and cytokines. The interest of the research is motivated by the current need to find new substances of natural origin which have demonstrated effectiveness in the described fields of application and low degree of toxicity for humans. Natural products provide a vast pool of NO inhibitors that can possibly be developed into clinical products. This article reviews some plenolic secondary metabolites from plants with NO inhibitory properties and their structure-activity relationship studies that can be focused for drug development programs.  相似文献   
110.
Cutaneous squamous cell carcinoma (cSCC) is one of the most common nonmelanoma skin cancer worldwilde, with a more invasive growth pattern and higher potential to metastatize than basal cell carcinoma. Although several risk factors have been linked to a high metastatic potential of cSCC, no widely accepted classification system for this common subtype of cancer exists. Herein we report an emblematic case of rapidly growing and metastatic cSCC and discuss the rate of growth of the tumour (ROG) as novel prognostic high risk surrogate marker.  相似文献   
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