938 resultados para Breast tumor
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Objective: To evaluate whether immunohistochemical marker studies performed on core needle biopsy (CNB) specimens accurately reflect the marker status of the tumor obtained from final surgical specimen. Methods: This was a retrospective study that used the database of the Division of Mastology of the Hospital das Clinicas, Sao Paulo, Brazil. Sixty-nine patients submitted to ultrasound-guided CNB diagnosed with breast cancer were retrospectively analyzed. Immunohistochemistry (IHC) on core biopsy specimens was compared to that of excisional biopsy regarding estrogen receptor (ER), progesterone receptor (PR), human epidermal gowth factor receptor 2 gene (HER2), p53, and Ki67. The analysis of the concordance between CNB and surgical biopsy was performed using the kappa (k) coefficient (95% CI). Results: A perfect concordance between the labeling in the surgical specimens and the preoperative biopsies in p53 (k = 1.0; 95% CI: 0.76-1.0) was identified. There was an almost perfect concordance for ER (k = 0.89; 95% CI: 0.65-1.0) and a substantial concordance for PR (k = 0.70; 95% CI: 0.46-0.93). HER2 (k = 0.61; 95% CI: 0.38-0.84) and Ki-67 (k = 0.74; 95% CI: 0.58-0.98) obtained a substantial concordance this analysis. Conclusion: The results of this study indicate that the immunohistochemical analysis of ER, PR, Ki-67, and p53 from core biopsy specimens provided results that accurately reflect the marker status of the tumor. The concordance rate of HER2 was less consistent; although it produced substantial concordance, values were very close to moderate concordance.
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Under many circumstances, the host constituents that are found in the tumor microenvironment support a malignancy network and provide the cancer cells with advantages in proliferation, invasiveness and metastasis establishment at remote organs. It is known that Toll like receptors (TLRs) are expressed not only on immune cells but also on cancer cells and it has suggested a deleterious role for TLR3 in inflammatory disease. Hypothesizing that altered IFN gamma signaling may be a key mechanism of immune dysfunction common to cancer as well CXCR4 is overexpressed among breast cancer patients, the mRNA expression of TLR3, CXCR4 and IFN gamma in breast cancer tumor tissues was investigated. No statistically significant differences in the expression of CXCR4 mRNA, IFN gamma and TLR3 between healthy and tumor tissues was observed, however, it was verified a positive correlation between mRNA relative expression of TLR3 and CXCR4 (p < 0.001), and mRNA relative expression of TLR3 was significantly increased in breast cancer tumor tissue when compared to healthy mammary gland tissue among patients expressing high IFN gamma (p = 0.001). Since the tumor microenvironment plays important roles in cancer initiation, growth, progression, invasion and metastasis, it is possible to propose that an overexpression of IFN gamma mRNA due to the pro-inflammatory microenvironment can lead to an up-regulation of CXCR4 mRNA and consequently to an increased TLR3 mRNA expression even among nodal negative patients. In the future, a comprehensive study of TLR3, CXCR4 and IFN gamma axis in primary breast tumors and corresponding healthy tissues will be crucial to further understanding of the cancer network.
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N-4-Phenyl 2-acetylpyridine thiosemicarbazone (H2Ac4Ph; N-(phenyl)-2-(1-(pyridin-2-yl)ethylidene) hydrazinecarbothioamide) and its N-4-ortho-, -meta- and -para-fluorophenyl (H2Ac4oFPh, H2Ac4mFPh, H2Ac4pFPh), N-4-ortho-, -meta- and -para-chlorophenyl (H2Ac4oClPh, H2Ac4mClPh, H2Ac4pClPh), N-4-ortho-, -meta- and -para-iodophenyl (H2Ac4oIPh, H2Ac4mIPh, H2Ac4pIPh) and N-4-ortho-, -meta- and -para-nitrophenyl (H2Ac4oNO(2)Ph, H2Ac4mNO(2)Ph, H2Ac4pNO(2)Ph) derivatives were assayed for their cytotoxicity against human malignant breast (MCF-7) and glioma (T98G and U87) cells. The compounds were highly cytotoxic against the three cell lineages (IC50: MCF-7, 52-0.16 nM; T98G, 140-1.0 nM; U87, 160-1.4 nM). All tested thiosemicarbazones were more cytotoxic than etoposide and did not present any haemolytic activity at up to 10(-5) M. The compounds were able to induce programmed cell death. H2Ac4pClPh partially inhibited tubulin assembly at high concentrations and induced cellular microtubule disorganization. (C) 2012 Elsevier Ltd. All rights reserved.
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The presence of tumor-initiating cells (CD44(+)/CD24(-)) in solid tumors has been reported as a possible cause of cancer metastasis and treatment failure. Nevertheless, little is know about the presence of CD44(+)/CD24(-) cells within the primary tumor and metastasis. The proportion of CD44(+)/CD24(-) cells was analyzed in 40 samples and in 10 lymph node metastases using flow cytometry phenotyping. Anti-human CD326 (EpCam; FITC), antihuman CD227 (MUC-1; FITC), anti-human CD44 (APC), and anti-human CD24 (PE), anti-ABCG2 (PE), and anti-CXCR4 (PeCy7) were used for phenotype analysis. The mean patient age was 60.5 years (range, 33-87 years); mean primary tumor size (pT) was 1.8 cm (0.5-3.5 cm). The Wilcoxon or Kruskal-Wallis test was used for univariate analyses. Logistic regression was used for multivariate analysis. The median percentage of CD44(+)/CD24(-) cells within primary invasive ductal carcinomas (IDC) was 2.7% (range, 0.2-71.2). In lymph node metastases, we observed a mean of 6.1% (range, 0.07-53.7). The percentage of CD44(+)/CD24(-) cells in IDCs was not associated with age, pT, tumor grade and HER2. We observed a significantly enrichment of CD44(+)/CD24(-) and ABCG2(+) cells in ESA(+) cell population in patients with positive lymph nodes (P = 0.02 and P = 0.04, respectively). Our data suggest that metastatic dissemination is associated with an increase in tumorinitiating cells in stage I and II breast cancer.
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Abstract Background Rhodium (II) citrate (Rh2(H2cit)4) has significant antitumor, cytotoxic, and cytostatic activity on Ehrlich ascite tumor. Although toxic to normal cells, its lower toxicity when compared to carboxylate analogues of rhodium (II) indicates Rh2(H2cit)4 as a promising agent for chemotherapy. Nevertheless, few studies have been performed to explore this potential. Superparamagnetic particles of iron oxide (SPIOs) represent an attractive platform as carriers in drug delivery systems (DDS) because they can present greater specificity to tumor cells than normal cells. Thus, the association between Rh2(H2cit)4 and SPIOs can represent a strategy to enhance the former's therapeutic action. In this work, we report the cytotoxicity of free rhodium (II) citrate (Rh2(H2cit)4) and rhodium (II) citrate-loaded maghemite nanoparticles or magnetoliposomes, used as drug delivery systems, on both normal and carcinoma breast cell cultures. Results Treatment with free Rh2(H2cit)4 induced cytotoxicity that was dependent on dose, time, and cell line. The IC50 values showed that this effect was more intense on breast normal cells (MCF-10A) than on breast carcinoma cells (MCF-7 and 4T1). However, the treatment with 50 μM Rh2(H2cit)4-loaded maghemite nanoparticles (Magh-Rh2(H2cit)4) and Rh2(H2cit)4-loaded magnetoliposomes (Lip-Magh-Rh2(H2cit)4) induced a higher cytotoxicity on MCF-7 and 4T1 than on MCF-10A (p < 0.05). These treatments enhanced cytotoxicity up to 4.6 times. These cytotoxic effects, induced by free Rh2(H2cit)4, were evidenced by morphological alterations such as nuclear fragmentation, membrane blebbing and phosphatidylserine exposure, reduction of actin filaments, mitochondrial condensation and an increase in number of vacuoles, suggesting that Rh2(H2cit)4 induces cell death by apoptosis. Conclusions The treatment with rhodium (II) citrate-loaded maghemite nanoparticles and magnetoliposomes induced more specific cytotoxicity on breast carcinoma cells than on breast normal cells, which is the opposite of the results observed with free Rh2(H2cit)4 treatment. Thus, magnetic nanoparticles represent an attractive platform as carriers in Rh2(H2cit)4 delivery systems, since they can act preferentially in tumor cells. Therefore, these nanopaticulate systems may be explored as a potential tool for chemotherapy drug development.
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Background Vitamin D transcriptional effects were linked to tumor growth control, however, the hormone targets were determined in cell cultures exposed to supra physiological concentrations of 1,25(OH)2D3 (50-100nM). Our aim was to evaluate the transcriptional effects of 1,25(OH)2D3 in a more physiological model of breast cancer, consisting of fresh tumor slices exposed to 1,25(OH)2D3 at concentrations that can be attained in vivo. Methods Tumor samples from post-menopausal breast cancer patients were sliced and cultured for 24 hours with or without 1,25(OH)2D3 0.5nM or 100nM. Gene expression was analyzed by microarray (SAM paired analysis, FDR≤0.1) or RT-qPCR (p≤0.05, Friedman/Wilcoxon test). Expression of candidate genes was then evaluated in mammary epithelial/breast cancer lineages and cancer associated fibroblasts (CAFs), exposed or not to 1,25(OH)2D3 0.5nM, using RT-qPCR, western blot or immunocytochemistry. Results 1,25(OH)2D3 0.5nM or 100nM effects were evaluated in five tumor samples by microarray and seven and 136 genes, respectively, were up-regulated. There was an enrichment of genes containing transcription factor binding sites for the vitamin D receptor (VDR) in samples exposed to 1,25(OH)2D3 near physiological concentration. Genes up-modulated by both 1,25(OH)2D3 concentrations were CYP24A1, DPP4, CA2, EFTUD1, TKTL1, KCNK3. Expression of candidate genes was subsequently evaluated in another 16 samples by RT-qPCR and up-regulation of CYP24A1, DPP4 and CA2 by 1,25(OH)2D3 was confirmed. To evaluate whether the transcripitonal targets of 1,25(OH)2D3 0.5nM were restricted to the epithelial or stromal compartments, gene expression was examined in HB4A, C5.4, SKBR3, MDA-MB231, MCF-7 lineages and CAFs, using RT-qPCR. In epithelial cells, there was a clear induction of CYP24A1, CA2, CD14 and IL1RL1. In fibroblasts, in addition to CYP24A1 induction, there was a trend towards up-regulation of CA2, IL1RL1, and DPP4. A higher protein expression of CD14 in epithelial cells and CA2 and DPP4 in CAFs exposed to 1,25(OH)2D3 0.5nM was detected. Conclusions In breast cancer specimens a short period of 1,25(OH)2D3 exposure at near physiological concentration modestly activates the hormone transcriptional pathway. Induction of CYP24A1, CA2, DPP4, IL1RL1 expression appears to reflect 1,25(OH)2D3 effects in epithelial as well as stromal cells, however, induction of CD14 expression is likely restricted to the epithelial compartment.
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Abstract Background Cancer stem cell (CSC) hypothesis postulates that tumors are maintained by a self-renewing CSC population that is also capable of differentiating into non-self-renewing cell populations that constitute the bulk of tumor. Stem cells renewal and differentiation can be directly influenced by the oxygen levels of determined tissues, probably by the reduction of oxidative DNA damage in hypoxic regions, thus leading to a friendlier microenvironment, regarding to clonal expansion and for resistance to chemotherapeutic regimens. Furthermore, there have been strong data indicating a pivotal role of hypoxic niche in cancer stem cells development. There are evidence that hypoxia could drive the maintenance of CSC, via HIF-1α expression, but it still to be determined whether hypoxia markers are expressed in breast tumors presenting CD44+CD24-/low immunophenotype. Methods Immunohistochemical analysis of CD44+CD24-/low expression and its relationship with hypoxia markers and clinical outcome were evaluated in 253 samples of breast ductal carcinomas. Double-immunolabeling was performed using EnVision Doublestain System (Dako, Carpinteria, CA, USA). Slides were then scanned into high-resolution images using Aperio ScanScope XT and then, visualized in the software Image Scope (Aperio, Vista, CA, USA). Results In univariate analysis, CD44+CD24-/low expression showed association with death due to breast cancer (p = 0.035). Breast tumors expressing CD44+CD24-/low immunophenotype showed relationship with HIF-1α (p = 0.039) and negativity for HER-2 (p = 0.013). Conclusion Considering that there are strong evidences that the fraction of a tumour considered to be cancer stem cells is plastic depending upon microenvironmental signals, our findings provide further evidence that hypoxia might be related to the worse prognosis found in CD44+CD24-/low positive breast tumors.
Coexistence of benign phyllodes tumor and invasive ductal carcinoma in distinct breasts: case report
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This report describes a rare case of coexistence of benign phyllodes tumor, which measured 9 cm in the right breast, and invasive ductal carcinoma of 6 cm in the left breast, synchronous and independent, in a 66-year-old patient. The patient underwent a bilateral mastectomy due to the size of both lesions. Such situations are rare and usually refer to the occurrence of ductal or lobular carcinoma in situ when associated with malignant phyllodes tumors, and more often in ipsilateral breast or intra-lesional.
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Os tumores neuroendócrinos primários de mama (TNPMs) são incomuns e não há consenso quanto a tratamento e prognóstico. No presente trabalho, foram revisados os diagnósticos de 1.184 pacientes com câncer de mama atendidos no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (HCFMRP/USP), identificando três casos que preenchiam os critérios de TNPM, segundo classificação estabelecida pela Organização Mundial da Saúde (OMS) em 2003. Foram avaliados os achados clinicopatológicos e imuno-histoquímicos e as terapias realizadas, buscando caracterizar os padrões histopatológicos e de comportamento distintos dos carcinomas convencionais de mama.
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Basal-like tumor is an aggressive breast carcinoma subtype that displays an expression signature similar to that of the basal/myoepithelial cells of the breast tissue. Basal-like carcinoma are characterized by over-expression of the Epidermal Growth Factor receptor (EGFR), high frequency of p53 mutations, cytoplasmic/nuclear localization of beta-catenin, overexpression of the Hypoxia inducible factor (HIF)-1alpha target Carbonic Anhydrase isoenzime 9 (CA9) and a gene expression pattern similar to that of normal and cancer stem cells, including the over-expression of the mammary stem cell markers CD44. In this study we investigated the role of p53, EGFR, beta-catenin and HIF-1alpha in the regulation of stem cell features and genes associated with the basal-like gene expression profile. The findings reported in this investigation indicate that p53 inactivation in ductal breast carcinoma cells leads to increased EGFR mRNA and protein levels. In our experimental model, EGFR overexpression induces beta-catenin cytoplasmatic stabilization and transcriptional activity and, by that, leads to increased aggressive features including mammosphere (MS) forming and growth capacity, invasive potential and overexpression of the mammary stem cell gene CD44. Moreover we found that EGFR/beta-catenin axis promotes hypoxia survival in breast carcinoma cells via increased CA9 expression. Indeed beta-catenin positively regulates CA9 expression upon hypoxia exposure. Interestingly we found that beta-catenin inhibits HIF-1alpha transcriptional activity. Looking for the mechanism, we found that CA9 expression is promoted by HIF-1alpha and cytoplasmatic beta-catenin further increased it post-transcriptionally, via direct mRNA binding and stabilization. These data reveal a functional beta-catenin/HIF-1alpha interplay among hallmarks of basal-like tumors and unveil a new functional role for cytoplasmic beta-catenin in the phenotype of such tumors. Therefore it can be proposed that the interplay here described among EGFR/beta-catenin and HIF-1alpha may play a role in breast cancer stem cell survival and function.
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Cancer is a multi-step process in which both the activation of oncogenes and the inactivation of tumor suppressor genes alter the normal cellular programs to a state of proliferation and growth. The regulation of a number of tumor suppressor genes and the mechanism underlying the tumor suppression have been intensively studied. Hugl-1 and Hugl-2, the human homologues of Drosophila lgl are shown to be down-regulated in a variety of cancers including breast, colon, lung and melanoma, but the mechanism responsible for loss of expression is not yet known. The regulation of gene expression is influenced by factors inducing or repressing transcription. The present study was focused on the identification and characterization of the active promoters of Hugl-1 and Hugl-2. Further, the regulation of the promoter and functional consequences of this regulation by specific transcription factors was analyzed. Experiments to delineate the function of the mouse homologue of Hugl-2, mgl2 using transgenic mice model were performed. This study shows that the active promoter for both Hugl-1 and Hugl-2 is located 1000bp upstream of transcription start sites. The study also provides first insight into the regulation of Hugl-2 by an important EMT transcriptional regulator, Snail. Direct binding of Snail to four E-boxes present in Hugl-2 promoter region results in repression of Hugl-2 expression. Hugl-1 and Hugl-2 plays pivotal role in establishment and maintenance of cell polarity in a diversity of cell types and organisms. Loss of epithelial cell polarity is a prerequisite for cancer progression and metastasis and is an important step in inducing EMT in cells. Regulation of Hugl-2 by Snail suggests one of the initial events towards loss of epithelial cell polarity during Snail-mediated EMT. Another important finding of this study is the induction of Hugl-2 expression can reverse the Snail-driven EMT. Inducing Hugl-2 in Snail expressing cells results in the re-expression of epithelial markers E-cadherin and Cytokeratin-18. Further, Hugl-2 also reduces the rate of tumor growth, cell migration and induces the epithelial phenotype in 3D culture model in cells expressing Snail. Studies to gain insight into the signaling pathways involved in reversing Snail-mediated EMT revealed that induction of Hugl-2 expression interferes with the activation of extracellular receptor kinase, Erk. Functional aspects of mammalian lgl in vivo was investigated by establishing mgl2 conditional knockout mice. Though disruption of mgl2 gene in hepatic tissues did not alter the growth and development, ubiquitous disruption of mgl2 gene causes embryonic lethality which is evident by the fact that no mgl2-/- mice were born.
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This study deals with the discovery and characterization of EXN6 and EXN11 as novel tumor-associated proteins. EXN6 is mainly present in breast and ovary cancers (40 and 35%) while EXN11 is mainly detected in primary and metastatic colon cancer (40%). A characterization of the two proteins confirmed that they could be novel targets for cancer therapy.
Synthese von tumor-assoziierten MUC1-Mucin-Glycopeptid-Vakzinen und deren immunologische Evaluierung
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Eine alternative Methode zur Therapie von Tumorerkrankungen bestünde in einer Immuntherapie ausgelöst durch synthetische Antitumor-Vakzine. Ein vielversprechendes Zielmolekül für eine solche Aktivimmunisierung ist das Glycoprotein MUC1, das auf nahezu allen Epithelgeweben exprimiert und auf Tumorgeweben stark überexprimiert wird. Seine extrazelluläre Domäne enthält eine Vielzahl von Tandem-Repeat-Sequenzen der Art: HGVTSAPDTRPAPGSTAPPA mit fünf potentiellen O-Glycosylierungs-Positionen. Da die Form der Glycosylierung des MUC1 in Tumorzellen stark von der auf normalen Zellen abweicht, liegen auf Tumorzellen eine Reihe tumor-assoziierter Saccharidantigene und Peptidepitope vor.rnIn dieser Arbeit wurden tumor-assoziierte Glycopeptidantigene aus der MUC1-Tandem-Repeat-Region hergestellt. Die synthetisierten MUC1-Glycopeptide tragen in verschiedenen Positionen eine Glycosylierung mit den tumor-assoziierten Tn- und STn-Saccharid-Antigenen. Zur Gewinnung von Vakzinen wurden diese Glycopeptid-Antigene über einen Spacer mit immunstimulierenden Komponenten verknüpft. Als Immunstimulanzien wurden ein T-Zell-Epitop aus dem Ovalbumin (OVA323-339) sowie die Carrier-Proteine Rinderserumalbumin (BSA) und Tetanus-Toxoid (TTox) verwendet. rnDie synthetischen MUC1-Glycopeptide wurden durch Immunisierung von Mäusen einer immunologischen Evaluierung unterzogen. Insbesondere die synthetischen MUC1-Glycopeptid-TTox-Vakzine lösen sehr starke Immunantworten aus. Es konnte gezeigt werden, dass die induzierten Antikörper stark an Tumorzellen und auch an Mammakarzinom-Gewebe binden, was für die Entwicklung von Antitumor-Vakzinen als vielversprechend einzustufen ist.
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Triple negative breast cancer (TNBC) is a very aggressive tumor subtype characterized by the lack of expression of estrogen receptor 1 (ESR1), due in the most of cases to an increased expression of DNA methyltransferases (DNMTs) and hypermethylation in CpG islands, resulting in gene silencing. Furthermore, in ESR1- negative breast cancers, androgen receptor (AR) is highly expressed and some studies suggest that it can drive tumor progression and might represent a therapeutic target. A correlation between microRNAs, small non-coding RNAs that regulate gene expression, and DNMTs was investigated in a TNBC cell line to restore a normal methylation pattern of ESR1, leading to its re-expression and conferring again sensitivity to selective estrogen receptor modulators (SERMs). miR-148A and miR-29B were found to be involved in the reduction of the expression of DNMT1 and DNMT3A and in a slight increase of ESR1 expression, but not at protein level. Then, we found a down-regulation of AR by miRs-7, -9, -27a, -27b, -29a, -29b, -29c, -127-3p, -127-5p and -376 at 48h post transfection and an up-regulation by miR-15a and miR-16 at every time considered. We concomitantly investigated a possible increase of Tamoxifen, Herceptin and Metformin sensitivity after AR silencing in MDA-MB 453 and T-47D cell lines. Cells seemed more sensitive when silenced for AR only in MDA-MB-453 at 24h post Tamoxifen treatment. Studies on Metformin have basically confirmed an increase of drug sensitivity due to AR silencing in both cell lines. Analysis of Herceptin showed how MDA-MB 453 samples silenced for AR have a slight decrease in the percentage of proliferating cells, demonstrating a possible increase in the response to treatment. These preliminary data provide the basis for further study of the modulation of the expression of AR by microRNAs and it will be interesting to understand the molecular mechanisms underlying these interactions.
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Breast cancer (BC) is the most often diagnosed cancer entity of women worldwide. No molecular biomarkers are usable in the clinical routine for the early detection of BC. Proteomics is one of the dynamic tools for the successful examination of changes on the protein level. In this thesis different proteomics-based investigations were performed for the detection of protein and autoantibody biomarkers in serum samples of BC and healthy (CTRL) subjects. First, protein levels of candidates from previous profiling studies were investigated via antibody-microarray platform. Three proteins were found in distinct levels in both groups: secretoglobin family 1D member 1, alpha-2 macroglobulin and inter-alpha-trypsin inhibitor heavy chain family member 4. The second part was dedicated to the de novo exploration of potentially immunogenic tumor antigens (TA’s) with immunoprecipitation and Western immunoblotting followed by identification over mass spectrometry. Autoantibody levels were verified in individual serum profiling via the protein microarray platform. Two autoantibody’ cohorts (anti-Histone 2B and anti-Recoverin) were found in different levels in both groups. The findings of this PhD thesis underline deregulated serum protein and autoantibody levels in the presence of BC. Further investigations are needed to confirm the results in an independent study population.