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991.
Ultraviolet irradiation of mammalian cells induces several events that include activation of growth factor receptors and triggering of signal transduction pathway. Most of the UV responses are mediated by the production of reactive oxygen species (ROS) and can be blocked by antioxidants. In this study, we analysed the effect of UVB irradiation at physiologic doses and that of the pro-oxidant agent cumene hydroperoxide (CUH) on the activation of the receptor for keratinocyte growth factor (KGF), a key mediator of epithelial growth and differentiation. Exposure to both UVB (30-150 mJ/cm(2)) and CUH (200 microM of NIH3T3 KGFR (KGF receptors) transfectants caused a rapid tyrosine phosphorylation and activation of KGFR similar to that induced by KGF, and internalization of the activated receptor. The KGFR expression appeared unmodified by the treatments. Ultrastructural observations of both UVB- and CUH-treated cells showed a normal morphology of the plasma membranes and intracellular organelles. The antioxidant N-acetylcysteine inhibited UVB-induced receptor phosphorylation. The generation of an intracellular oxidative stress was detected as a decrease of catalase activity and of vitamin E, and reduced glutathione levels, whereas superoxide dismutase activity was not significantly modified. A peroxidation of polyunsaturated fatty acids of cell membranes was observed after both treatments, associated with the intracellular oxidative stress. Similar biochemical events were observed on NIH3T3 untransfected control cells, suggesting that KGFR activation follows intracellular generation of ROS and is not associated with a scavenging effect. Taken together our results demonstrate that exposure to UVB and to oxidant stimuli induces a rapid intracellular production of ROS, which in turn are capable of triggering KGFR activation and internalization, similar to those induced by KGF.  相似文献   
992.
The recombinant monoclonal antibody trastuzumab has antiproliferative effect on breast cancer (BC) cells with ErbB2 overexpression. We postulated that a mechanism able to modify ErbB2 expression enhances the antitumor effect of trastuzumab. We analyzed whether granulocyte-colony stimulating factor (G-CSF), widely used in adjuvant cancer therapy to alleviate chemotherapy-induced myelotoxicity, could influence ErbB2 expression in BC cells and patients. The expression of ErbB2 (Herceptest) was analyzed in four BC cell lines (BT474, SKBR3, ZR75.1, and T47D) treated with G-CSF and in five samples biopsies from BC patients subjected to G-CSF rescue after chemotherapy. The effects of G-CSF and trastuzumab alone or their combination on cell growth and apoptosis were investigated. G-CSF receptor was detected on all cell lines and BC patients. G-CSF induced upregulation of ErbB2 in SKBR3, ZR75, and T47D cells. This modulation was not associated with an increase in tumor cell growth in vitro. Trastuzumab alone inhibited colony formation in soft agar but did not induce apoptosis on BC cells with no or low ErbB2 genomic amplification. The combination of trastuzumab and G-CSF enhanced the inhibition of tumor colony formation and induced apoptosis on these cells. This effect was further increased by G-CSF pretreatment. Five of nine BC patients showed an increase of Herceptest score after G-CSF administration. G-CSF treatment increases ErbB2 expression in vitro and in vivo enhancing the activity of trastuzumab on BC cell lines inducing apoptosis of BC cells with low or no ErbB2 genomic amplification.  相似文献   
993.
Objective: Consumption of olive oil may cause postprandial impairment of endothelial function, while acute ingestion of red wine seems to improve it. The purpose of the present study was to investigate the combined postprandial effects of two essential components of the Mediterranean diet, red wine and olive oil, on endothelial function.

Methods: Fifteen healthy subjects were enrolled in the study, which was comprised of 4 study days. Subjects were asked to consume a standard meal at each study day containing 50gr of olive oil and 250 ml of wine. Two types of wine (red and white; rich and poor in antioxidants respectively) and two types of olive oil (green and refined; rich and poor in antioxidants respectively) were used in a 2*2 design. Endothelium dependent, flow mediated dilatation (FMD) was measured with a B-Mode ultrasound device at fast and 1, 2 and 3 hours postprandially.

Results: Combined consumption of red wine and green olive oil (both rich in antioxidants) improved FMD postprandially (p = 0.002, ANOVA for repeated measures), which remained significant 1 hour (p = 0.002) and 2 hours (0.037) following the meal compared to fasting levels. No other combination of wine and olive oil caused any significant alteration on FMD.

Conclusion: Acute consumption of both red wine and green olive oil, rich in antioxidants, led to an improvement in the postprandial endothelial function in healthy subjects. These findings provide an additional favorable effect of components of the Mediterranean diet and of their antioxidant substances on endothelial function, at the postprandial state.  相似文献   
994.

Introduction

Histologic transformation from NSCLC to SCLC is a mechanism of resistance in EGFR-mutant tumors but is also occasionally observed in nonmutated NSCLC.

Methods

We performed a multicenter retrospective collection of cases presenting between 2005 and 2017. The objectives were to analyze survival data and to define epidemiologic, clinical, treatment and histomolecular characteristics at both the time of diagnosis of NSCLC and of SCLC.

Results

Forty-eight EGFR-mutant NSCLC and 13 non–EGFR-mutant cases were registered. Most EGFR-mutant tumors retained the same EGFR mutation after transformation. The median time to SCLC transformation was shorter in the EGFR-mutant group than in non-EFGR mutants (16 months versus 26 months (p = 0.01)). Both tumors were responsive to platinum etoposide regimens (45% partial response for the EGFR-mutant group versus 40% for non-EFGR mutants). The median overall survival rates were 28 months in the EGFR-mutant group versus 37 months in the non–EFGR-mutant group, respectively. After transformation, the median overall survival was 9 months in the non–EGFR-mutant group versus 10 months in the EGFR-mutant group.

Conclusions

Transformation into SCLC seems to occur more quickly in EGFR mutated tumors; however, once the tumor is transformed its survival and response to treatment seems comparable to that of classical SCLC.  相似文献   
995.

Background

Benign liver tumors are common. They do not spread to other areas of the body, and they usually do not pose a serious health risk. In fact, in most cases, benign liver tumors are not diagnosed because patients are asymptomatic. When they are detected, it’s usually because the person has had medical imaging tests, such as an ultrasound (US), computed tomography (CT) scan, or magnetic resonance imaging (MRI), for another condition.

Materials and methods

A search of the literature was made using cancer literature and the PubMed, Scopus, and Web of Science (WOS) database for the following keywords: “hepatic benign tumors”, “hepatic cystic tumors”, “polycystic liver disease”, “liver macroregenerative nodules”, “hepatic mesenchymal hamartoma”, “hepatic angiomyolipoma”, “biliary cystadenoma”, and “nodular regenerative hyperplasia”.

Discussion and conclusion

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in some areas of the world; there is an increasing incidence worldwide. Approximately 750,000 new cases are reported per year. More than 75 % of cases occur in the Asia-Pacific region, largely in association with chronic hepatitis B virus (HBV) infection. The incidence of HCC is increasing in the USA and Europe because of the increased incidence of hepatitis C virus (HCV) infection. Unlike the liver HCC, benign tumors are less frequent. However, they represent a chapter always more interesting of liver disease. In fact, a careful differential diagnosis with the forms of malignant tumor is often required in such a way so as to direct the patient to the correct therapy. In conclusion, many of these tumors present with typical features in various imaging studies. On occasions, biopsies are required, and/or surgical removal is needed. In the majority of cases of benign hepatic tumors, no treatment is indicated. The main indication for treatment is the presence of significant clinical symptoms or suspicion of malignancy or fear of malignant transformation.  相似文献   
996.
Tobacco and alcohol use are the main risk factors for oral and oropharyngeal cancers, yet, dietary habits may also be of importance. Data from a series of case-control studies conducted in 9 countries worldwide (1,670 cases and 1,732 controls) were used to investigate the role of several food groups and body mass index (BMI). Low BMI significantly increased the odds ratio (OR) of cancer more than 2-fold among ever- and never-tobacco users and ever- and never-alcohol drinkers. After adjustment for potential confounders, high intake of fruits and vegetables significantly reduced the OR of cancer compared to low intake among ever-tobacco users (OR 0.4, 95% confidence interval [CI] 0.3-0.6), although not among never-tobacco users (OR 1.1, 95% CI 0.6-2.0). Similarly, the protective effect of high fruit and vegetable consumption was present among ever-drinkers (OR 0.4, 95% CI 0.3-0.6), but not among never-drinkers (OR 1.0, 95% CI 0.6-1.6). In conclusion, low BMI increases the risk of oral cancer, and vegetables and fruits may modulate the carcinogenic effects of tobacco and alcohol.  相似文献   
997.
A new series of pyrazolotriazolopyrimidines bearing different substitutions on the phenylcarbamoyl moieties at the N5 position, being highly potent and selective human A(3) adenosine receptor antagonists, is described. The compounds represent an extension and an improvement of our previous work on this class of compounds (J. Med. Chem. 1999, 42, 4473-4478; J. Med. Chem. 2000, 43, 4768-4780). All the synthesized compounds showed A(3) adenosine receptor affinity in the subnanomolar range and high levels of selectivity in radioligand binding assays at the human A(1), A(2A), A(2B), and A(3) adenosine receptors. In particular, the effect of the substitution and its position on the phenyl ring have been studied. From binding data, it is evident that the unsubstituted derivatives on the phenyl ring (e.g., compound 59, hA(3) = 0.16 nM, hA(1)/hA(3) = 3713, hA(2A)/hA(3) = 2381, hA(2B)/hA(3) = 1388) showed the best profile in terms of affinity and selectivity at the human A(3) adenosine receptors. The introduction of a sulfonic acid moiety at the para position on the phenyl ring was attempted in order to design water soluble derivatives. However, this substitution led to a dramatic decrease of affinity at all four adenosine receptor subtypes. A computer-generated model of the human A(3) receptor was built and analyzed to better interpret these results, demonstrating that steric control, in particular at the para position on the phenyl ring, plays a fundamental role in the receptor interaction. Some of the synthesized compounds proved to be full antagonists in a specific functional model, where the inhibition of cAMP-generation by IB-MECA was measured in membranes of CHO cells stably transfected with the human A(3) receptor with IC(50) values in the nanomolar range, with a statistically significative linear relationship with the binding data.  相似文献   
998.
999.
Leukemic cells from Chronic Lymphocytic Leukemia (CLL) patients interact with stromal cells of the surrounding microenvironment. Mesenchymal Stromal Cells (MSCs) represent the main population in CLL marrow stroma, which may play a key role for disease support and progression. In this study we evaluated whether MSCs influence in vitro CLL cell survival. MSCs were isolated from the bone marrow of 46 CLL patients and were characterized by flow cytometry analysis. Following co-culture of MSCs and leukemic B cells, we demonstrated that MSCs were able to improve leukemic B cell viability, this latter being differently dependent from the signals coming from MSCs. In addition, we found that the co-culture of MSCs with leukemic B cells induced an increased production of IL-8, CCL4, CCL11, and CXCL10 chemokines.As far as drug resistance is concerned, MSCs counteract the cytotoxic effect of Fludarabine/Cyclophosphamide administration in vivo, whereas they do not protect CLL cells from the apoptosis induced by the kinase inhibitors Bafetinib and Ibrutinib. The evidence that leukemic clones are conditioned by environmental stimuli suggest new putative targets for therapy in CLL patients.  相似文献   
1000.
OBJECTIVE: In this article we provide evidence of a significant spontaneous humoral response in cancer patients. METHODS: A panel of tumor-associated antigens, previously identified through serological screening of phage-displayed cDNA libraries from solid human tumors, breast carcinoma cell lines and human testis by employing breast cancer patient sera, was used in this study to survey sera from 182 patients with known disease histories and clinical stages. RESULTS: This analysis reveals a statistically significant association between tumor disease and presence in peripheral blood of IgG antibodies against four autoantigens. One of these antigens (D7-1) is particularly interesting in that the antibody response against it grows with cancer progression from stages I through IV, with an incidence of 13.2, 13.5, 18.2 and 27%, respectively. The significance of this stage-dependent increase in the incidence is confirmed by the Mantel-Haenszel Chi-squared test (P=0.001). CONCLUSIONS: Our data confirm association between breast cancer diagnosis of patients and presence in their peripheral blood of antibodies against several autoantigens identified by phage display.  相似文献   
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