70 research outputs found

    Photocurable polymethacrylate-silica nanocomposites: correlation between dispersion stability, curing kinetics, morphology and properties

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    A comprehensive study of model systems based on poly(ethylene glycol) dimethacrylate and two methacryloxy-modified silicas (Aerosil R7200 and R711) were investigated to find possible correlation between the stability of the monomer/silica dispersion, curing kinetics, composite morphology and physical and mechanical properties of the final hybrid material. The monomer/silica dispersions were cured photochemically. The investigated parameters: Zeta potential, polymerization rate and conversion, glass transition, surface roughness and mechanical properties were found to be synchronous; when plotted as function of silica content, they showed maxima or changes in the trend at the same filler loading. This threshold (optimum) silica content in the composition was about 5 wt.-% for the investigated systems. The results obtained are discussed in terms of the solvation cell (which influences dispersion stability) and the interphase layer formation as well as their changes below and above of the threshold filler content

    RSK1 promotes murine breast cancer growth and metastasis

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    Introduction. Triple-negative breast cancer (TNBC), representing over 15% of all breast cancers, has a poorerprognosis than other subtypes. There is no effective targeted treatment available for the TNBC sufferers. Ribosomal S6 kinases (RSKs) have been previously proposed as drug targets for TNBC based on observations that 85% of these tumors express activated RSKs.Materials and methods. Herein we examined an involvement of RSK1 (p90 ribosomal S6 kinase 1) in a regulation of TNBC growth and metastatic spread in an animal model, which closely imitates human disease. Micewere inoculated into mammary fat pad with 4T1 cells or their RSK1-depleted variant. We examined tumorgrowth and formation of pulmonary metastasis. Boyden chamber, wound healing and soft agarose assays wereperformed to evaluate cells invasion, migration and anchorage-independent growth.Results. We found that RSK1 promoted tumor growth and metastasis in vivo. After 35 days all animals inoculatedwith control cells developed tumors while in the group injected with RSK1-negative cells, there were 75%tumor-bearing mice. Average tumor mass was estimated as 1.16 g and 0.37 g for RSK1-positive vs. -negativesamples, respectively (p < 0.0001). Quantification of the macroscopic pulmonary metastases indicated that micewith RSK1-negative tumors developed approximately 85% less metastatic foci on the lung surface (p < 0.001).This has been supported by in vitro data presenting that RSK1 promoted anchorage-independent cell growthand migration. Moreover, RSK1 knock-down corresponded with decreased expression of cell cycle regulatingproteins, i.e. cyclin D3, CDK6 and CDK4.Conclusions. We provide evidence that RSK1 supports tumor growth and metastatic spread in vivo as well asin vitro migration and survival in non-adherent conditions. Further studies of RSK1 involvement in TNBC progression may substantiate our findings, laying the foundations for development of anti-RSK1-based therapeuticstrategies in the management of patients with TNBC

    Tetraspanin CD151 is a novel prognostic marker in poor outcome endometrial cancer

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    BACKGROUND: Type II cancers account for 10% of endometrial cancers but 50% of recurrence. Response rates to chemotherapy at recurrence are poor and better prognostic markers are needed to guide therapy. CD151 is a small transmembrane protein that regulates cell migration and facilitates cancer metastasis. High CD151 expression confers poor prognosis in breast, pancreatic and colorectal cancer. The prognostic significance of tetraspanin CD151 expression in poor outcome endometrial cancers was evaluated, along with oestrogen receptor (ER), progesterone receptor (PR), p53, human epidermal growth factor receptor -2 (HER-2), and CD 151 staining compared with α6β1, α3β1 integrins, and E-cadherin. METHODS: Tissue microarray constructed from 156 poor outcome endometrial cancers, tested with immunohistochemistry and staining correlated with clinicopathological data were used. A total of 131 data sets were complete for analysis. RESULTS: Expression of CD151 was significantly higher in uterine papillary serous and clear cell carcinoma than in grade 3 endometrioid carcinoma, sarcoma or carcinosarcoma (P<0.001). In univariate analysis, age, stage, histology type and CD151 were significant for both recurrence free (RFS) and disease specific survival (DSS). In multivariate analyses, CD151 was significant for RFS and DSS (P=0.036 and 0.033, respectively) in triple negative (ER, PR and HER-2 negative) tumours (88/131). The HER-2, p53, ER and PR were not prognostic for survival. There was strong concordance of CD151 with E-cadherin (98%), but not with α6β1 (35%), α3β1 staining (60%). CONCLUSION: The CD151 is a novel marker in type 2 cancers that can guide therapeutic decisions. CD151 may have an important role in tumourigenesis in some histology types

    Lack of CD151/integrin alpha 3 beta 1 complex is predictive of poor outcome in node-negative lobular breast carcinoma: opposing roles of CD151 in invasive lobular and ductal breast cancers

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    background: The proposed involvement of CD151 in breast cancer (BCa) progression is based on findings from studies in invasive ductal carcinoma (IDC). The IDC and invasive lobular carcinoma (ILC) represent distinct disease entities. Here we evaluated clinical significance of CD151 alone and in association with integrin α3β1 in patients with ILC in context of the data of our recent IDC study. methods: Expression of CD151 and/or integrin α3β1 was evaluated in ILC samples (N=117) using immunohistochemistry. The findings were analysed in relation to our results from an IDC cohort (N=182) demonstrating a prognostic value of an expression of CD151/integrin α3β1 complex in patients with HER2-negative tumours. results: Unlike in the IDCs, neither CD151 nor CD151/α3β1 complex showed any correlation with any of the ILC characteristics. Lack of both CD151 and α3β1 was significantly correlated with poor survival (P=0.034) in lymph node-negative ILC N(−) cases. The CD151−/α3β1− patients had 3.12-fold higher risk of death from BCa in comparison with the rest of the ILC N(−) patients. conclusions: Biological role of CD151/α3β1 varies between ILC and IDC. Assessment of CD151/α3β1 might help to identify ILC N(−) patients with increased risk of distant metastases

    Remodeling of extracellular matrix by normal and tumor-associated fibroblasts promotes cervical cancer progression

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    Background: Comparison of tissue microarray results of 29 cervical cancer and 27 normal cervix tissue samples using immunohistochemistry revealed considerable reorganization of the fibrillar stroma of these tumors. Preliminary densitometry analysis of laminin-1, α -smooth muscle actin (SMA) and fibronectin immunostaining demonstrated 3.8-fold upregulation of laminin-1 and 5.2-fold increase of SMA in the interstitial stroma, indicating that these proteins and the activated fibroblasts play important role in the pathogenesis of cervical cancer. In the present work we investigated the role of normal and tumor-associated fibroblasts. Methods: In vitro models were used to throw light on the multifactorial process of tumor-stroma interaction, by means of studying the cooperation between tumor cells and fibroblasts. Fibroblasts from normal cervix and cervical cancers were grown either separately or in co-culture with CSCC7 cervical cancer cell line. Changes manifest in secreted glycoproteins, integrins and matrix metallo-proteases (MMPs) were explored. Results: While normal fibroblasts produced components of interstitial matrix and TGF- β 1 that promoted cell proliferation, cancer-associated fibroblasts (CAFs) synthesized ample amounts of laminin-1. The following results support the significance of laminin-1 in the invasion of CSCC7 cells: 1.) Tumor-associated fibroblasts produced more laminin-1 and less components of fibrillar ECM than normal cells; 2.) The production of laminin chains was further increased when CSCC7 cells were grown in co-culture with fibroblasts; 3.) CSCC7 cells were capable of increasing their laminin production; 4.) Tumor cells predominantly expressed integrin α 6 β 4 laminin receptors and migrated towards laminin. The integrin profile of both normal and tumor-associated fibroblasts was similar, expressing receptors for fibronectin, vitronectin and osteopontin. MMP-7 secreted by CSCC7 cells was upregulated by the presence of normal fibroblasts, whereas MMP-2 produced mainly by fibroblasts was activated in the presence of CSCC7 cells. Conclusions: Our results indicate that in addition to degradation of the basement membrane, invasion of cervical cancer is accomplished by the remodeling of the interstitial stroma, which process includes decrease and partial replacement of fibronectin and collagens by a laminin-rich matrix

    Wplyw lubinu trwalego i sosny pospolitej na zmiany skladnikow odzywczych gleby lesnej

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    Przeprowadzone badania z uprawą łubinu trwałego i sosny pospolitej wykazały, że uprawa tych roślin wpływa na nieznaczne obniżenie kwasowości gleby badanych obiektów. Jednocześnie porównanie składników odżywczych wykazało nieznaczny wzrost zawartości azotu ogółem, w szczególności w obiektach z łubinem oraz nieznaczny spadek zawartości przyswajalnych form fosforu. Większą zawartość azotu amonowego i azotanowego stwierdzono w glebie obiektów z sosną i łubinem. Zawartość potasu i magnezu niepodlegała wyraźnym zmianom. Nie stwierdzono wyraźnych zmian zawartości mikroskładników w glebie porównywanych obiektów po zakończeniu wegetacji roślin.The research carried out on long-standing lupine and a common pine showed that the cultivation of these plants causes a slight lowering of soil acidity on the studied objects. At the same time the comparison of nutritional components revealed a slight increase of total nitrogen content especially in soil with long-standing lupine, and a slightly decreased content of available forms of phosphorus. The larger content of ammonia and nitrate nitrogen was observed in soil of objects soil of after common pine and lupine. The contents of potassium and magnesium were not clearly changed. The clear changes of micro-component content were not noted in soil of compared objects after ending of those plants’ vegetation
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