950 resultados para Protein Expression Screening


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During initial development, both X chromosomes are active in females, and one of them must be silenced at the appropriate time in order to dosage compensate their gene expression levels to male counterparts. Silencing involves epigenetic mechanisms, including histone deacetylation. Major X chromosome inactivation (XCI) in bovine occurs between hatching and implantation, although in vitro culture conditions might disrupt the silencing process, increasing or decreasing X-linked gene expression. In this study, we aimed to address the roles of histone deacetylase inhibition by trichostatin A (TSA) on female preimplantation development.We tested the hypothesis that by enhancing histone acetylation, TSA would increase the percentage of embryos achieving 16-cell stage, reducing percentage of embryos blocked at 8-cell stage, and interfere with XCI in IVF embryos. We noticed that after TSA treatment, acetylation levels in individual blastomeres of 8-16 cell embryos were increased twofold on treated embryos, and the samewas detected for blastocysts. Changes among blastomere levels within the same embryo were diminished on TSA group, as low-acetylated blastomeres were no longer detected. The percentage of embryos that reached the 5th cleavage cycle 118 h after IVF, analyzed by Hoechst staining, remained unaltered after TSA treatment. Then, we assessed XIST and G6PD expression in individual female bovine blastocysts by quantitative real-time PCR. Even though G6PD expression remained unaltered after TSA exposure, XIST expression was eightfold decreased, and we also detected a major decrease in the percentage of blastocysts expressing detectable XIST levels after TSA treatment. Based on these results, we conclude that HDAC is involved on XCI process in bovine embryos, and its inhibition might delay X chromosome silencing and attenuate aberrant XIST expression described for IVF embryos. © 2013 Society for Reproduction and Fertility.

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High-grade prostate cancers express high levels of matrix metalloproteinases (MMPs), major enzymes involved in tumor invasion and metastasis. However, the tumor cell lines commonly employed for prostate cancer research express only small amounts of MMPs when cultivated as monolayer cultures, in common culture media. The present study was conducted to ascertain whether culture conditions that include fibronectin can alter MMP2 and MMP9 expression by the human prostatic epithelial cell lines RWPE-1, LNCaP and PC-3. These cells were individually seeded at 2×104cells/cm2, cultivated until they reached 80% confluence, and then exposed for 4h to fibronectin, after which the conditioned medium was analyzed by gelatin zymography. Untreated cells were given common medium. Only RWPE-1 cells express detectable amounts of MMP9 when cultivated in common medium, whereas the addition of fibronectin induced high expression levels of pro and active forms of MMP2 in all tested cell lines. Our findings demonstrate that normal and tumor prostate cell lines express MMP2 activity when in contact with extracellular matrix components or blood plasma proteins such as fibronectin. Future studies of transcriptomes and proteomes in prostate cancer research using these cell lines should not neglect these important conclusions. © 2012 Elsevier Inc..

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The purpose of this study is to determine the expression of CCL19, CCL21, and CCR7 in samples of oral squamous cell carcinoma (OSCC) and their relationship with clinical and microscopic parameters. A comparative analysis was made of the mRNA expression of these chemokines and receptor in OSCC and normal oral mucosa. The immunoexpression of CCR7, CCL19, and CCL21 was also verified in OSCC and lymph nodes. Statistical significance was accepted at P < 0.05. Similar levels of CCR7, CCL19, and CCL21 mRNA in OSCC and normal oral mucosa were seen. A low expression of CCL19 and CCL21 in the intra- and peritumoral regions was observed. Scarce CCL19+ and CCL21+ cells were also noted in metastatic and non-metastatic lymph nodes. No association was found between the expression of these chemokines and clinical and microscopic parameters. Our findings would suggest that CCL19 and CCL21 may not be associated with cervical lymph node metastasis or other clinical and microscopic factors in OSCC. © 2012 International Society of Oncology and BioMarkers (ISOBM).

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The aim of this study was to investigate the expression of vascular endothelial growth factor type C (VEGF-C) in oral squamous cell carcinoma (OSCC) cell lines through norepinephrine-induced activation of beta-adrenergic receptors. Human OSCC cell lines (SCC-9 and SCC-25) expressing beta-adrenergic receptors were stimulated with different concentrations of norepinephrine (0.1, 1, and 10 μM) and 1 μM of propranolol, and analyzed after 1, 6, and 24 h. VEGF-C gene expression and VEGF-C production in the cell supernatant were evaluated by real-time PCR and by ELISA, respectively. The results showed that beta-adrenergic receptor stimulation by different concentrations of norepinephrine or blocking by propranolol did not markedly alter VEGF-C expression by SCC-9 and SCC-25 cells. VEGF-C protein levels produced by oral malignant cell lines after stimulation with different norepinephrine concentrations or blocking with propranolol was statistically similar (p > 0.05) to those of the control group (nonstimulated OSCC cell lines). Our findings suggest that stimulation of beta-adrenergic receptors by means of norepinephrine does not seem to modulate the VEGF-C expression in OSCC cell lines. These findings reinforce the need for further studies in order to understand the responsiveness of oral cancer to beta-adrenergic receptor stimulation or blockage, especially with regard to VEGF-C production. © 2012 International Society of Oncology and BioMarkers (ISOBM).

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Gastric cancer is a leading cause of cancer-related mortality, and the presence of lymph node metastasis an important prognostic factor. Downregulation of RKIP has been associated with tumor progression and metastasis in several types of neoplasms, being currently categorized as a metastasis suppressor gene. Our aim was to determine the expression levels of RKIP in gastric tissues and to evaluate its impact in the clinical outcome of gastric carcinoma patients. RKIP expression levels were studied by immunohistochemistry in a series of gastric tissues. Overall, we analysed 222 non-neoplastic gastric tissues, 152 primary tumors and 42 lymph node metastasis samples. We observed that RKIP was highly expressed in ∼83% of non-neoplastic tissues (including normal tissue and metaplasia), was lost in ∼56% of primary tumors and in ∼90% of lymph node metastasis samples. Loss of RKIP expression was significantly associated with several markers of poor clinical outcome, including the presence of lymph node metastasis. Furthermore, the absence of RKIP protein constitutes an independent prognostic marker for these patients. In conclusion, RKIP expression is significantly lost during gastric carcinoma progression being almost absent in lymph node metastasis samples. Of note, we showed that the absence of RKIP expression is associated with poor outcome features of gastric cancer patients, this being also an independent prognostic marker.

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Objective. The anti-inflammatory proteins annexin-A1 and galectin-1 have been associated with tumor progression. This scenario prompted us to investigate the relationship between the gene and protein expression of annexin-A1 (ANXA1/AnxA1) and galectin-1 (LGALS1/Gal-1) in an inflammatory gastric lesion as chronic gastritis (CG) and gastric adenocarcinoma (GA) and its association with H. pylori infection. Methods. We analyzed 40 samples of CG, 20 of GA, and 10 of normal mucosa (C) by the quantitative real-time PCR (qPCR) technique and the immunohistochemistry assay. Results. High ANXA1 mRNA expression levels were observed in 90% (36/40) of CG cases (mean relative quantification RQ = 4.26 ± 2.03) and in 80% (16/20) of GA cases (mean RQ = 4.38 ± 4.77). However, LGALS1 mRNA levels were high (mean RQ = 2.44 ± 3.26) in 60% (12/20) of the GA cases, while low expression was found in CG (mean RQ = 0.43 ± 3.13; P < 0.01). Normal mucosa showed modest immunoreactivity in stroma but not in epithelium, while stroma and epithelium displayed an intense immunostaining in CG and GA for both proteins. Conclusion. These results have provided evidence that galectin-1 and mainly annexin-A1 are overexpressed in both gastritis and gastric cancer, suggesting a strong association of these proteins with chronic gastric inflammation and carcinogenesis. © 2013 Yvana Cristina Jorge et al.

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Urothelial bladder cancer (UBC) is a heterogeneous type of disease. It is urgent to screen biomarkers of tumour aggressiveness in order to clarify the clinical behaviour and to personalize therapy in UBC patients. Raf kinase inhibitory protein (RKIP) is a metastasis suppressor, and its downregulation is associated with metastatic events in an increasing number of solid tumours. We evaluated the clinical and prognostic significance of RKIP expression in patients with high risk of progression UBC. Using immunohistochemistry, we determined RKIP expression levels in a series of 81 patients with high-grade pT1/pTis or muscle-invasive UBC. Staining of CD31 and D2-40 was used to assess blood and lymphatic vessels, in order to distinguish between blood and lymphatic vessel invasion (LVI). We found that 90 % of pT1/pTis tumours, 94 % of non-muscle invasive papillary tumours and 76 % of the cases without LVI occurrence expressed RKIP in >10 % of cells. In this group, we observed a subgroup of tumours (42 %) in which the tumour centre was significantly more intensely stained than the invasion front. This heterogeneous pattern was observed in 63 % of the cases with LVI. Low RKIP expression was associated with poorer 5-year disease-free and overall survival rates, and remained as an independent prognostic factor for disease-free survival. Loss of RKIP expression may be an important prognostic factor for patients with high risk of progression bladder cancer. © 2013 Springer-Verlag Berlin Heidelberg.

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Chronic hepatitis C virus (HCV) infection is an important cause of morbidity and mortality globally, and often leads to end-stage liver disease. The DNA damage checkpoint pathway induces cell cycle arrest for repairing DNA in response to DNA damage. HCV infection has been involved in this pathway. In this study, we assess the effects of HCV NS2 on DNA damage checkpoint pathway. We have observed that HCV NS2 induces ataxia-telangiectasia mutated checkpoint pathway by inducing Chk2, however, fails to activate the subsequent downstream pathway. Further study suggested that p53 is retained in the cytoplasm of HCV NS2 expressing cells, and p21 expression is not enhanced. We further observed that HCV NS2 expressing cells induce cyclin E expression and promote cell growth. Together these results suggested that HCV NS2 inhibits DNA damage response by altering the localization of p53, and may play a role in the pathogenesis of HCV infection. © 2013 Bitter et al.

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The excision repair cross-complementation 1 (ERCC1) enzyme plays an essential role in the nucleotide excision repair pathway and is associated with resistance to platinum-based chemotherapy in different types of cancer. The aim of the present study was to evaluate the clinicopathological significance of ERCC1 expression in breast cancer patients. We analyzed the immunohistochemical expression of ERCC1 in a tissue microarray from 135 primary breast carcinomas and correlated the immunohistochemical findings with clinicopathological factors and outcome data. ERCC1 expression analysis was available for 109 cases. In this group, 58 (53.2%) were positive for ERCC1. ERCC1-positive expression was correlated with smaller tumor size (P=0.007) and with positivity for estrogen receptor (P=0.040), but no correlation was found with other clinicopathological features. Although not statistically significant, triple negative breast cancers were more frequently negative for ERCC1 (61.5% of the cases) compared to the non-triple negative breast cancer cases (41.5%). In conclusion, ERCC1 expression correlated significantly with favorable prognostic factors, such as smaller tumor size and ER-positivity, suggesting a possible role for ERCC1 as a predictive and/or prognostic marker in breast cancer. © 2013 Elsevier GmbH.

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Annexin A1 (AnxA1) is a protein that displays potent anti-inflammatory properties, but its expression in eye tissue and its role in ocular inflammatory diseases have not been well studied. We investigated the mechanism of action and potential uses of AnxA1 and its mimetic peptide (Ac2-26) in the endotoxin-induced uveitis (EIU) rodent model and in human ARPE-19 cells activated by LPS. In rats, analysis of untreated EIU after 24 and 48 h or EIU treated with topical applications or with a single s.c. injection of Ac2-26 revealed the anti-inflammatory actions of Ac2-26 on leukocyte infiltration and on the release of inflammatory mediators; the systemic administration of Boc2, a formylated peptide receptor (fpr) antagonist, abrogated the peptide's protective effects. Moreover, AnxA1-/- mice exhibited exacerbated EIU compared with wild-type animals. Immunohistochemical studies of ocular tissue showed a specific AnxA1 posttranslational modification in EIU and indicated that the fpr2 receptor mediated the anti-inflammatory actions of AnxA1. In vitro studies confirmed the roles of AnxA1 and fpr2 and the protective effects of Ac2-26 on the release of chemical mediators in ARPE-19 cells. Molecular analysis of NF-κB translocation and IL-6, IL-8, and cyclooxygenase-2 gene expression indicated that the protective effects of AnxA1 occur independently of the NF-κB signaling pathway and possibly in a posttranscriptional manner. Together, our data highlight the role of AnxA1 in ocular inflammation, especially uveitis, and suggest the use of AnxA1 or its mimetic peptide Ac2-26 as a therapeutic approach. Copyright © 2013 by The American Association of Immunologists, Inc.

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Few studies have focused on experimental testosterone deprivation in immature animals. Therefore, this study used sexually immature rats aiming to evaluate the testes and epididymis histology and proteins expression in these organs on PND50 and 75, after premature antiandrogen exposure, from PND21 to 44. Although the androgen deprivation from pre-puberty up to peripuberty did not alter the histological organization of the testes and epididymis either at puberty or at adulthood, the treatment impaired the expression of specific proteins in epididymal tissue at puberty and adulthood (androgen receptor, calmodulin, Rab11A). These changes may be related to impaired epididymal function, sperm quality and fertility capacity as observed in a previous study. Further studies are necessary to better investigate the molecular mechanisms involved in the impairment on reproductive competence of male rats after precocious hormonal injury. © 2013 Elsevier Inc.

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Colossoma macropomum, also known as tambaqui, is an economically important fish species, and interesting new studies have been published with the aim of improving the growth of this fish. In this work, we describe the morphometric characteristics, as well as the mRNA and protein expression levels of two myogenic regulatory factors (MRFs)-myod/MyoD and myogenin/Myogenin-in the white and red muscle types of tambaqui. A high proportion of white and red muscle fibers with large diameters suggest a hypertrophic growth process in the skeletal muscle during juvenile stages. Comparisons between muscle types showed that, in red muscle, myogenin transcript levels were significantly higher than those of myod. In contrast, MyoD protein levels were significantly higher than those of Myogenin in red muscle. These results suggest that in red and white muscles of juvenile tambaqui, independent post-transcriptional mechanisms for regulating MyoD and Myogenin expression may exist, which could be differentially activated during muscle growth. Furthermore, these data also suggest that specific control mechanisms may regulate distinct muscle phenotypes. © 2013 The Royal Swedish Academy of Sciences.

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FSH induces expansion of bovine cumulus-oocyte complexes (COCs) in cattle, which can be enhanced by oocyte-secreted factors (OSFs). In this study it was hypothesised that FSH stimulates COC expansion in part from direct stimulation of the epidermal growth factor (EGF)-like ligands amphiregulin (AREG), epiregulin (EREG) and betacellulin (BTC), but also in part through regulation of OSFs or their receptors in cumulus cells. Bovine COCs were cultured in defined medium with graded doses of FSH. In the absence of FSH, COCs did not expand. FSH caused cumulus expansion, and increased the abundance of AREG and EREG mRNA in a time- and dose-dependent manner, but decreased BTC mRNA levels. FSH had modest stimulatory effects on the levels of mRNA encoding the bone morphogenetic protein 15 (BMP15) receptor, BMPR1B, in cumulus cells, but did not alter mRNA expression of the growth and differentiation factor 9 (GDF9) receptor, TGFBR1. More interestingly, FSH dramatically stimulated levels of mRNA encoding two receptors for fibroblast growth factors (FGF), FGFR2C and FGFR3C, in cumulus cells. FSH also stimulated mRNA expression of FGFR1B, but not of FGFR2B in cumulus cells. Based on dose-response studies, FGFR3C was the receptor most sensitive to the influence of FSH. This study demonstrates that FSH stimulates the expression of EGF-like factors in bovine cumulus cells, and provides evidence that FSH differently regulates the expression of distinct receptors for OSFs in cumulus cells. © CSIRO 2013.

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The use of prognostic markers for breast cancer allows therapeutic strategies to be defined more efficiently. The expression of glutathione (GSH) and glutathione peroxidase (GPX) in tumor cells has been evaluated as a predictor of prognosis and response to cytotoxic treatments. Its immunoexpression was assessed in 63 women diagnosed with invasive ductal carcinoma in a retrospective study. The results showed that high GSH expression was associated with tumors negative for the estrogen receptor (ER) (P<0.05), and GPX expression was associated with tumors negative for the progesterone receptor (PR) and patient mortality. Focusing on the 37 patients who received adjuvant chemotherapy/radiotherapy (Group I), high expression of GPX was associated with a high rate of patient mortality (P<0.05). The 19 patients who received only adjuvant chemotherapy (Group II) showed high expression of GSH in relation to metastasis (P<0.05). In addition, high levels of GPX expression were significantly associated with a shorter overall survival (P<0.05). To confirm this, the expression of precursor genes of GSH [glutamate cysteine ligase (GCLC) and glutathione synthetase (GSS)] and the GPX gene was analyzed using quantitative PCR in cultured neoplastic mammary cells treated with doxorubicin. Doxorubicin treatment was able to eliminate tumor cells without alterations in the gene expression of GSS, but led to underexpression of the GCLC and GPX genes. Our results suggest that high levels of GPX may be related to the development of resistance to chemotherapy in these tumors, response to treatment and the clinical course of the breast cancer patients.

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Soft tissue sarcomas (STSs) are a heterogeneous group of mesenchymal tumors of >50 subtypes. However, STSs represent <1% of types of cancer. Despite this low frequency, the disease is aggressive and treatment, when possible, is based on traditional chemotherapies. A number of cases of resistance to adjuvant therapies have been reported. Metastases are commonly identified in STS patients during diagnosis and the development of effective clinical parameters is crucial for correct management of the disease. The use of biological markers in cancer is a useful tool to determine patient prognosis. Ki--67 is a protein marker for proliferation of somatic cells and is widely used in prognostic studies of various types of tumor, including STSs. Cluster of differentiation 100 (CD100) is a member of the semaphorin family. The family was initially described as axon guidance molecules important for angiogenesis, organogenesis, apoptosis and neoplasia. CD100 was previously utilized as a prognostic factor in tumors and also in STSs. In the present study, protein expression of Ki--67 and CD100 was analyzed by immunohistochemistry in samples of STS patients of the Barretos Cancer Hospital (Barretos, Brazil) to establish prognostic criteria of the disease. Results demonstrate a correlation between CD100 expression and poor prognosis, consistent with a previous study. Moreover, the expression of Ki-67 was identified to correlate with presence of local or locoregional recurrence. To the best of our knowledge, no large casuistic study has revealed this correlation between Ki--67 and local recurrence in STSs. The use of Ki--67 and CD100 as markers in clinical pathological analysis may be suitable as a prognostic criterion in disease progression.