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51.
We compared effects of antiangiogenic gene therapy with a combination of soluble sVEGFR-1, sVEGFR-2 and sVEGFR-3 to chemotherapy with carboplatin and paclitaxel and to antiangiogenic monoclonal anti-VEGF-antibody bevacizumab in an intraperitoneal ovarian cancer xenograft model in mice (n = 80). Gene therapy was also combined with chemotherapy. Therapy was initiated when sizable tumors were confirmed in magnetic resonance imaging (MRI). Adenovirus-mediated gene transfer was performed intravenously (2 × 109 pfu), while chemotherapy and monoclonal anti-VEGF-antibody were dosed intraperitoneally. The study groups were as follows: AdLacZ control (n = 21); combination of AdsVEGFR-1, -2 and -3 (n = 21); combination of AdsVEGFR-1, -2, -3 and paclitaxel (n = 9); bevacizumab (n = 14); paclitaxel (n = 9) and carboplatin (n = 5). Effectiveness was assessed by survival time and surrogate measures such as sequential MRI, immunohistochemistry, microvessel density and tumor growth. Antiangiogenic gene therapy combined with paclitaxel significantly prolonged the mean survival of mice (25 days) compared to the controls (15 days) and all other treatment groups (p = 0.001). Bevacizumab treatment did not have any significant effect on the survival. Tumors of the mice treated by gene therapy were significantly smaller than in the control group (p = 0.021). The mean vascular density and total vascular area were also significantly smaller in the tumors of the gene therapy group (p = 0.01). These results show potential of the antiangiogenic gene therapy to improve efficacy of chemotherapy with paclitaxel and support testing of this approach in a phase I clinical trial for the treatment of ovarian cancer.  相似文献   
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Matriptase‐2 (TMPRSS6) has been identified as a breast cancer risk factor. Here, we examined relationships between TMPRSS6 genetic variations and breast cancer risk and survival, and determined the gene and protein expressions in breast tumors and assessed their clinical importance. Thirteen TMPRSS6 polymorphisms were genotyped in 462 invasive breast cancer cases and 458 controls. Gene expression was analyzed from 83 tumors and protein expression from 370 tumors. We then assessed the statistical significance of associations among genotypes, clinicopathological characteristics and survival. The TMPRSS6 variant rs2543519 was associated with breast cancer risk (p = 0.032). Multivariate analysis showed that four variants had effects on survival—rs2543519 (p = 0.017), rs2235324 (p = 0.038), rs14213212 (p = 0.044) and rs733655 (p = 0.021)—which were used to create a group variable that was associated with poorer prognosis correlating with more alleles related to reduced survival (p = 0.006; risk ratio, 2.375; 95% confidence interval, 1.287–4.382). Low gene expression was related to triple‐negative breast cancer (p = 0.0001), and lower protein expression was detected in undifferentiated (p = 0.019), large (p = 0.014) and ductal or lobular tumors (p = 0.036). These results confirm the association of TMRRSS6 variants with breast cancer risk and survival. Matriptase‐2 levels decrease with tumor progression, and lower gene expression is seen in poor‐prognosis‐related triple‐negative breast cancers. Our study is the first to show that matriptase‐2 gene variants are related to breast cancer prognosis, supporting matriptase‐2 involvement in tumor development.  相似文献   
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Aim: To study the connection between reaction to soy milk and IgE sensitization to Gly m 4. Methods: Four subjects who experienced unforeseen and severe symptoms after the ingestion of soymilk were studied. Results: All children were birch pollen allergic, had high IgE responses to the PR‐10 proteins from birch and soybean, Bet v 1 and Gly m 4. All reactions took place after the ingestion of soymilk during the peak pollen season. Conclusion: This is the first time soybean‐dependant pollen‐food cross‐reaction has been reported in children experiencing reactions during the birch pollen season. These findings may well be helpful to doctors in identifying individuals at risk of severe reactions upon the ingestion of soymilk, and we foresee an increase in the number of similar cases as soy drinks are promoted for health purposes.  相似文献   
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Vascular endothelial growth factor C (VEGF-C) induces lymphangiogenesis via VEGF receptor 3 (VEGFR3), which is encoded by the most frequently mutated gene in human primary lymphedema. Angiopoietins (Angs) and their Tie receptors regulate lymphatic vessel development, and mutations of the ANGPT2 gene were recently found in human primary lymphedema. However, the mechanistic basis of Ang2 activity in lymphangiogenesis is not fully understood. Here, we used gene deletion, blocking Abs, transgene induction, and gene transfer to study how Ang2, its Tie2 receptor, and Tie1 regulate lymphatic vessels. We discovered that VEGF-C–induced Ang2 secretion from lymphatic endothelial cells (LECs) was involved in full Akt activation downstream of phosphoinositide 3 kinase (PI3K). Neonatal deletion of genes encoding the Tie receptors or Ang2 in LECs, or administration of an Ang2-blocking Ab decreased VEGFR3 presentation on LECs and inhibited lymphangiogenesis. A similar effect was observed in LECs upon deletion of the PI3K catalytic p110α subunit or with small-molecule inhibition of a constitutively active PI3K located downstream of Ang2. Deletion of Tie receptors or blockade of Ang2 decreased VEGF-C–induced lymphangiogenesis also in adult mice. Our results reveal an important crosstalk between the VEGF-C and Ang signaling pathways and suggest new avenues for therapeutic manipulation of lymphangiogenesis by targeting Ang2/Tie/PI3K signaling.  相似文献   
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BackgroundTumour-infiltrating mast cells (MCs) can remodel tumour microenvironment and growth by suppressing immune responses and potentiating angiogenesis. Furthermore, accumulation of MCs in follicular lymphoma (FL) correlates with unfavourable prognosis after immunochemotherapy. Here we investigated whether tumour vascularity is associated with MC content and outcome in FL patients treated with immunochemotherapy.Patients and methodsMicrovessel density (MVD) and MC content were determined immunohistochemically from pretreatment samples of 95 FL patients using CD31, CD34 and mast cell tryptase antibodies. Gene expression data from a separate set of 24 FL patients were analysed for comparison. All patients were treated with the combination of rituximab (R) and cyclophoshamide-doxorubicin–vincristine–prednisone (CHOP) chemotherapy.ResultsIncreased CD31+ MVD correlated positively with the number of tumour infiltrating MCs and CD34+ vessels, and negatively with the outcome. Overall survival and progression-free survival were significantly better among patients with low CD31+ MVDs. In multivariate analyses, CD31+ MVD had prognostic value independently of Follicular Lymphoma Prognostic Index but not of MC content. Consistent with the immunohistochemical data, high CD31/PECAM1 mRNA levels were associated with adverse outcome. Conversely, a positive prognostic impact of VEGF mRNA expression on the outcome was found.ConclusionVascularity is associated with MC content and outcome in R-CHOP-treated FL patients.  相似文献   
59.
To study the effect of various valvular heart diseases on the quantitative histology of myocardium, 38 human hearts with valvular lesions were examined (11 aortic stenoses, nine mitral stenoses, nine mitral incompetence and nine combined aortic and mitral valve lesions). The control group consisted of ten hearts without any valvular lesions. With morphometrical methods the volume fractions of myocardial components (myocardial fibres, interstitial space and diffuse connective tissue), the numerical density of arterioles and the mean fibre diameter were estimated. Myocardial fibrosis was more severe in hearts with valvular lesions than in the controls (5.4% vs 3.3%, P less than 0.01), but did not correlate with the anatomical severity of the valvular lesions. The most severe myocardial fibrosis was found in hearts with mitral incompetence (6.7%). Fibre hypertrophy was most severe in hearts with aortic stenosis and in hearts with mitral incompetence (22 microns and 23 microns, respectively). In hearts with severe valvular lesions the mean fibre diameter was 23 microns and in hearts with mild to moderate lesions 19 microns (P less than 0.01). Good correlation was observed between the mean fibre diameter and the weight of the left ventricle (r = 0.81, P less than 0.01). The volume fractions of connective tissue and interstitial space were significantly higher and the volume fraction of myocardial fibres was correspondingly lower in the subendocardium than in the subepicardium in hearts with either pressure overload (aortic stenosis) or volume overload (mitral incompetence). In conclusion, myocardial fibrosis occurs in patients with various valvular lesions, but the severity of the fibrosis does not correlate with the anatomical severity of valvular lesions.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
60.
Increasing evidence has recognized tight junctions (TJs) as the lower epidermal inside-out diffusion barrier located in granular cell layers of the epidermis. However, little is known about the regulation of TJ components in epidermis. p38 pathway is one of the mitogen-activated protein kinase pathways, which controls cell growth, differentiation, and apoptosis. We have investigated the role of p38 signaling pathway in the regulation of selected desmosomal, adherens and TJ components in human primary keratinocytes during Ca2+-induced differentiation, as well as in cultured squamous cell carcinoma cell lines. p38 signaling pathway was inhibited in cultured keratinocytes and cutaneous squamous cell carcinoma cells using recombinant adenoviruses, small inhibitory RNAs (siRNA) and chemical inhibitors. Expression of intercellular junction proteins was investigated using Western analysis and indirect immunofluorescence (IIF). The results showed that inhibition of p38δ function by siRNA or adenovirally delivered dominant negative mutant led to markedly decreased levels of Zonula occludens-1 (ZO-1) protein in keratinocytes, while the expression of other junctional proteins studied was not altered. Immunolocalization of ZO-1 revealed that intercellular junction areas were depleted from ZO-1. Inhibition of ZO-1 by siRNA silencing did not however result in an altered expression or subcellular localization of other TJ components studied. The expression of ZO-1 in carcinoma cells was also regulated by p38. The results indicate that ZO-1 is regulated by p38δ while the other junction proteins studied are not. Since ZO-1 is an integral component of functional TJs, various pathological processes affecting signaling via p38δ may also interfere with epithelial maturation and the formation and function of TJs.  相似文献   
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