871 resultados para triple-negative carcinomas


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The Notch1 gene has an important role in mammalian cell-fate decision and tumorigenesis. Upstream control mechanisms for transcription of this gene are still poorly understood. In a chemical genetics screen for small molecule activators of Notch signalling, we identified epidermal growth factor receptor (EGFR) as a key negative regulator of Notch1 gene expression in primary human keratinocytes, intact epidermis and skin squamous cell carcinomas (SCCs). The underlying mechanism for negative control of the Notch1 gene in human cells, as well as in a mouse model of EGFR-dependent skin carcinogenesis, involves transcriptional suppression of p53 by the EGFR effector c-Jun. Suppression of Notch signalling in cancer cells counteracts the differentiation-inducing effects of EGFR inhibitors while, at the same time, synergizing with these compounds in induction of apoptosis. Thus, our data reveal a key role of EGFR signalling in the negative regulation of Notch1 gene transcription, of potential relevance for combinatory approaches for cancer therapy.

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Biomarker analysis is playing an essential role in cancer diagnosis, prognosis, and prediction. Quantitative assessment of immunohistochemical biomarker expression on tumor tissues is of clinical relevance when deciding targeted treatments for cancer patients. Here, we report a microfluidic tissue processor that permits accurate quantification of the expression of biomarkers on tissue sections, enabled by the ultra-rapid and uniform fluidic exchange of the device. An important clinical biomarker for invasive breast cancer is human epidermal growth factor receptor 2 [(HER2), also known as neu], a transmembrane tyrosine kinase that connotes adverse prognostic information for the patients concerned and serves as a target for personalized treatment using the humanized antibody trastuzumab. Unfortunately, when using state-of-the-art methods, the intensity of an immunohistochemical signal is not proportional to the extent of biomarker expression, causing ambiguous outcomes. Using our device, we performed tests on 76 invasive breast carcinoma cases expressing various levels of HER2. We eliminated more than 90% of the ambiguous results (n = 27), correctly assigning cases to the amplification status as assessed by in situ hybridization controls, whereas the concordance for HER2-negative (n = 31) and -positive (n = 18) cases was 100%. Our results demonstrate the clinical potential of microfluidics for accurate biomarker expression analysis. We anticipate our technique will be a diagnostic tool that will provide better and more reliable data, onto which future treatment regimes can be based.

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BACKGROUND: The stimulation of efferent renal sympathetic nerve activity induces sequential changes in renin secretion, sodium excretion, and renal hemodynamics that are proportional to the magnitude of the stimulation of sympathetic nerves. This study in men investigated the sequence of the changes in proximal and distal renal sodium handling, renal and systemic hemodynamics, as well as the hormonal profile occurring during a sustained activation of the sympathetic nervous system induced by various levels of lower body negative pressure (LBNP). METHODS: Ten healthy subjects were submitted to three levels of LBNP ranging between 0 and -22.5 mm Hg for one hour according to a triple crossover design, with a minimum of five days between each level of LBNP. Systemic and renal hemodynamics, renal water and sodium handling (using the endogenous lithium clearance technique), and the neurohormonal profile were measured before, during, and after LBNP. RESULTS: LBNP (0 to -22.5 mm Hg) induced an important hormonal response characterized by a significant stimulation of the sympathetic nervous system and gradual activations of the vasopressin and the renin-angiotensin systems. LBNP also gradually reduced water excretion and increased urinary osmolality. A significant decrease in sodium excretion was apparent only at -22.5 mm Hg. It was independent of any change in the glomerular filtration rate and was mediated essentially by an increased sodium reabsorption in the proximal tubule (a significant decrease in lithium clearance, P < 0.05). No significant change in renal hemodynamics was found at the tested levels of LBNP. As observed experimentally, there appeared to be a clear sequence of responses to LBNP, the neurohormonal response occurring before the changes in water and sodium excretion, these latter preceding any change in renal hemodynamics. CONCLUSIONS: These data show that the renal sodium retention developing during LBNP, and thus sympathetic nervous stimulation, is due mainly to an increase in sodium reabsorption by the proximal segments of the nephron. Our results in humans also confirm that, depending on its magnitude, LBNP leads to a step-by-step activation of neurohormonal, renal tubular, and renal hemodynamic responses.

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The present work describes a fast gas chromatography/negative-ion chemical ionization tandem mass spectrometric assay (Fast GC/NICI-MS/MS) for analysis of tetrahydrocannabinol (THC), 11-hydroxy-tetrahydrocannabinol (THC-OH) and 11-nor-9-carboxy-tetrahydrocannabinol (THC-COOH) in whole blood. The cannabinoids were extracted from 500 microL of whole blood by a simple liquid-liquid extraction (LLE) and then derivatized by using trifluoroacetic anhydride (TFAA) and hexafluoro-2-propanol (HFIP) as fluorinated agents. Mass spectrometric detection of the analytes was performed in the selected reaction-monitoring mode on a triple quadrupole instrument after negative-ion chemical ionization. The assay was found to be linear in the concentration range of 0.5-20 ng/mL for THC and THC-OH, and of 2.5-100 ng/mL for THC-COOH. Repeatability and intermediate precision were found less than 12% for all concentrations tested. Under standard chromatographic conditions, the run cycle time would have been 15 min. By using fast conditions of separation, the assay analysis time has been reduced to 5 min, without compromising the chromatographic resolution. Finally, a simple approach for estimating the uncertainty measurement is presented.

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The objective of this work was to combine the advantages of the dried blood spot (DBS) sampling process with the highly sensitive and selective negative-ion chemical ionization tandem mass spectrometry (NICI-MS-MS) to analyze for recent antidepressants including fluoxetine, norfluoxetine, reboxetine, and paroxetine from micro whole blood samples (i.e., 10 microL). Before analysis, DBS samples were punched out, and antidepressants were simultaneously extracted and derivatized in a single step by use of pentafluoropropionic acid anhydride and 0.02% triethylamine in butyl chloride for 30 min at 60 degrees C under ultrasonication. Derivatives were then separated on a gas chromatograph coupled with a triple-quadrupole mass spectrometer operating in negative selected reaction monitoring mode for a total run time of 5 min. To establish the validity of the method, trueness, precision, and selectivity were determined on the basis of the guidelines of the "Société Française des Sciences et des Techniques Pharmaceutiques" (SFSTP). The assay was found to be linear in the concentration ranges 1 to 500 ng mL(-1) for fluoxetine and norfluoxetine and 20 to 500 ng mL(-1) for reboxetine and paroxetine. Despite the small sampling volume, the limit of detection was estimated at 20 pg mL(-1) for all the analytes. The stability of DBS was also evaluated at -20 degrees C, 4 degrees C, 25 degrees C, and 40 degrees C for up to 30 days. Furthermore, the method was successfully applied to a pharmacokinetic investigation performed on a healthy volunteer after oral administration of a single 40-mg dose of fluoxetine. Thus, this validated DBS method combines an extractive-derivative single step with a fast and sensitive GC-NICI-MS-MS technique. Using microliter blood samples, this procedure offers a patient-friendly tool in many biomedical fields such as checking treatment adherence, therapeutic drug monitoring, toxicological analyses, or pharmacokinetic studies.

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OBJECTIVES: Immunohistochemistry (IHC) has become a promising method for pre-screening ALK-rearrangements in non-small cell lung carcinomas (NSCLC). Various ALK antibodies, detection systems and automated immunostainers are available. We therefore aimed to compare the performance of the monoclonal 5A4 (Novocastra, Leica) and D5F3 (Cell Signaling, Ventana) antibodies using two different immunostainers. Additionally we analyzed the accuracy of prospective ALK IHC-testing in routine diagnostics. MATERIALS AND METHODS: Seventy-two NSCLC with available ALK FISH results and enriched for FISH-positive carcinomas were retrospectively analyzed. IHC was performed on BenchMarkXT (Ventana) using 5A4 and D5F3, respectively, and additionally with 5A4 on Bond-MAX (Leica). Data from our routine diagnostics on prospective ALK-testing with parallel IHC, using 5A4, and FISH were available from 303 NSCLC. RESULTS: All three IHC protocols showed congruent results. Only 1/25 FISH-positive NSCLC (4%) was false negative by IHC. For all three IHC protocols the sensitivity, specificity, positive (PPV) and negative predictive values (NPV) compared to FISH were 96%, 100%, 100% and 97.8%, respectively. In the prospective cohort 3/32 FISH-positive (9.4%) and 2/271 FISH-negative (0.7%) NSCLC were false negative and false positive by IHC, respectively. In routine diagnostics the sensitivity, specificity, PPV and NPV of IHC compared to FISH were 90.6%, 99.3%, 93.5% and 98.9%, respectively. CONCLUSIONS: 5A4 and D5F3 are equally well suited for detecting ALK-rearranged NSCLC. BenchMark and BOND-MAX immunostainers can be used for IHC with 5A4. True discrepancies between IHC and FISH results do exist and need to be addressed when implementing IHC in an ALK-testing algorithm.

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Human papillomavirus (HPV) infections of the high-risk types are strongly linked to the development of cervical carcinoma. The HPV oncoproteins E6 and E7 are thought to play a crucial role in this process through their interactions with the p53 protein and the retinoblastoma susceptibility gene product pRb, respectively. E6 binds to p53 protein promoting its degradation. This is considered to contribute to the oncogenesis of HPV-associated anogenital cancer. On the other hand, in HPV-negative cervical carcinoma, p53 mutations are thought to have a role in the transformation process. A total of 122 HPV-positive cervical carcinoma tissue samples were evaluated for the presence of mutations in exons 5-8 of the p53 gene by single-stranded conformation polymorphism analysis and DNA sequencing. Only four missense point mutations were detected. These findings suggest that other mechanisms independent of p53 inactivation may play a role in the genesis of cervical carcinomas.

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Malignancy of pulmonary large cell carcinomas (LCC) increases from classic LCC through LCC with neuroendocrine morphology (LCCNM) to large cell neuroendocrine carcinomas (LCNEC). However, the histological classification has sometimes proved to be difficult. Because the malignancy of LCC is highly dependent on proteins with functions in the cell cycle, DNA repair, and apoptosis, p53 has been targeted as a potentially useful biological marker. p53 mutations in lung cancers have been shown to result in expression and protein expression also occurs in the absence of mutations. To validate the importance of both p53 protein expression (by immunostaining) and p53 gene mutations in lung LCC (by PCR-single strand conformational polymorphism analysis of exons 5, 6, 7, and 8) and to study their relationships with clinical factors and sub-classification we investigated the correlation of p53 abnormalities in 15 patients with LCC (5 classic LCC, 5 LCNEC, and 5 LCCNM) who had undergone resection with curative intent. Of these patients, 5/15 expressed p53 and none had mutant p53 sequences. There was a negative survival correlation with positive p53 immunostaining (P = 0.05). After adjustment for stage, age, gender, chemotherapy, radiotherapy, and histological subtypes by multivariate analysis, p53 expression had an independent impact on survival. The present study indicates that p53 assessment may provide an objective marker for the prognosis of LCC irrespective of morphological variants and suggests that p53 expression is important for outcome prediction in patients with the early stages of LCC. The results reported here should be considered to be initial results because tumors from only 15 patients were studied: 5 each from LCC, LCNEC and LCCNM. This was due to the rarity of these specific diseases.

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Bien qu’on ait longtemps considéré le désespoir ou la souffrance comme un facteur de précipitation de l’expérience religieuse, aucune étude n’a été effectuée sur les liens entre une expérience d’abus sexuels et une conversion religieuse subséquente. Une revue de la littérature sur la dynamique religieuse des abus sexuels révèle deux paradigmes opposés : la religion comme ressource ou comme facteur de risque. De même, un examen des études sur la conversion indique trois dichotomies : un converti actif ou passif, une conversion soudaine ou progressive, et la conversion comme phénomène normal ou pathologique. Or, un recensement des témoignages anecdotiques de victimes d’abus sexuels qui ont subséquemment vécu une conversion suggère que l'interaction entre les deux événements est plus complexe. Pour dépasser ces dichotomies paradigmatiques, nous préconisons une approche narrative. Plus spécifiquement, nous utilisons le concept d’identité narrative développé par Paul Ricœur. Ce concept s’inscrit dans la dynamique ricœurienne de triple mimèsis, laquelle assure une fonction de liaison entre le champ pratique et le champ narratif. De façon générale, notre stratégie méthodologique consiste à déterminer comment, à partir d’éléments biographiques issus de la préfiguration (mimèsis I), le sujet configure son récit pour donner sens à son expérience (mimèsis II) et la refigure pour aboutir à une identité de survivant ou de converti (mimèsis III). Sept entrevues non directives ont été effectuées auprès de personnes qui ont subi des abus sexuels durant leur enfance et qui ont plus tard vécu une conversion religieuse dans le milieu évangélique. À partir de l'analyse en trois étapes mentionnée ci-dessus, nous évaluons la contribution positive ou négative des divers éléments narratifs et, surtout, de leur interaction à la construction de l’identité narrative du sujet. Nous en concluons que le rapport entre des abus sexuels subis durant l’enfance et une conversion ultérieure n’est pas si simple que la littérature pourrait le laisser soupçonner. La conversion peut s’avérer salutaire à la survie du sujet et contribuer à la guérison du traumatisme sexuel qu’il a subi. Toutefois, certains éléments religieux peuvent faire obstacle au processus de recouvrement. Ces éléments nocifs varient d’un sujet à l’autre, et ce qui est délétère pour l’un peut être bénéfique pour l’autre, selon la configuration du récit.

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Deuterium (dD) and oxygen (d18O) isotopes are powerful tracers of the hydrological cycle and have been extensively used for paleoclimate reconstructions as they can provide information on past precipitation, temperature and atmospheric circulation. More recently, the use of 17Oexcess derived from precise measurement of d17O and d18O gives new and additional insights in tracing the hydrological cycle whereas uncertainties surround this proxy. However, 17Oexcess could provide additional information on the atmospheric conditions at the moisture source as well as about fractionations associated with transport and site processes. In this paper we trace water stable isotopes (dD, d17O and d18O) along their path from precipitation to cave drip water and finally to speleothem fluid inclusions for Milandre cave in northwestern Switzerland. A two year-long daily resolved precipitation isotope record close to the cave site is compared to collected cave drip water (3 months average resolution) and fluid inclusions of modern and Holocene stalagmites. Amount weighted mean dD, d18O and d17O are �71.0‰, �9.9‰, �5.2‰ for precipitation, �60.3‰, �8.7‰, �4.6‰ for cave drip water and �61.3‰, �8.3‰, �4.7‰ for recent fluid inclusions respectively. Second order parameters have also been derived in precipitation and drip water and present similar values with 18 per meg for 17Oexcess whereas d-excess is 1.5‰ more negative in drip water. Furthermore, the atmospheric signal is shifted towards enriched values in the drip water and fluid inclusions (D of ~ þ 10‰ for dD). The isotopic composition of cave drip water exhibits a weak seasonal signal which is shifted by around 8e10 months (groundwater residence time) when compared to the precipitation. Moreover, we carried out the first d17O measurement in speleothem fluid inclusions, as well as the first comparison of the d17O behaviour from the meteoric water to the fluid inclusions entrapment in speleothems. This study on precipitation, drip water and fluid inclusions will be used as a speleothem proxy calibration for Milandre cave in order to reconstruct paleotemperatures and moisture source variations for Western Central Europe.

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Objective. The objective of this study was to evaluate in vivo the revascularization and the apical and periapical repair after endodontic treatment using 2 techniques for root canal disinfection (apical negative pressure irrigation versus apical positive pressure irrigation plus triantibiotic intracanal dressing) in immature dogs` teeth with apical periodontitis. Study design. Two test groups of canals with experimentally induced apical periodontitis were evaluated according to the disinfection technique: Group 1, apical negative pressure irrigation (EndoVac system), and Group 2, apical positive pressure irrigation (conventional irrigation) plus triantibiotic intracanal dressing. In Group 3 (positive control), periapical lesions were induced, but no endodontic treatment was done. Group 4 (negative control) was composed of sound teeth. The animals were killed after 90 days and the maxillas and mandibles were subjected to histological processing. The sections were stained with hematoxylin and eosin and Mallory Trichrome and examined under light microscopy. A description of the apical and periapical features was done and scores were attributed to the following histopathological parameters: newly formed mineralized apical tissue, periapical inflammatory infiltrate, apical periodontal ligament thickness, dentin resorption, and bone tissue resorption. Intergroup comparisons were done by the Kruskal-Wallis and Dunn`s tests (alpha = 0.05). Results. Although statistically significant difference was found only for the inflammatory infiltrate (P < .05), Group 1 presented more exuberant mineralized formations, more structured apical and periapical connective tissue, and a more advanced repair process than Group 2. Conclusion. From the histological observations, sodium hypochlorite irrigation with the EndoVac system can be considered as a promising disinfection protocol in immature teeth with apical periodontitis, suggesting that the use of intracanal antibiotics might not be necessary. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010; 109: 779-787)

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Lip squamous cell carcinoma (SCC) may develop from a premalignant condition, actinic cheilitis (AC) in 95% of the cases. Both premalignant and neoplastic lip diseases are caused mainly by chronic exposure to the ultraviolet component of solar radiation, especially UVB. This exposure causes disruption of the cell cycle and damage to DNA repair systems, like mismatch repair, altering proteins repair as hMLH1 and hMSH2. This research aimed to investigate the immunohistochemical expression of hMLH1 and hMSH2 proteins in lower lip SCCs and ACs, providing additional information about carcinogenesis of the lower lip. The sample consisted 40 cases of ACs and 40 cases of lower lip SCCs. Histological sections of 3 μm were submitted to immunoperoxidase method, for immunohistochemical analysis of lesions were counted in 1000 cells (positive and negative), data were evaluated both in absolute numbers and percentage of immunostained cells, the latter by assigning scores. Associations of the variables and comparative analysis of biomarker expression were performed by Fisher s exact and Pearson s chi-square, "t" student, one-way ANOVA, Mann- Whitney e Kruskal-Wallis tests. The level of significance was 5%. It was found that, in lower lip SCC, the mean of the proteins was higher in female patients (hMLH1= 369,80 + 223,98; hMHS2 = 534,80 + 343,62), less than 50 years old (hMLH1 = 285,50 + 190,65; hMHS2 = 540,00 + 274,79) and classified as low-grade malignancy (hMLH1 = 264,59 + 179,21; hMHS2 = 519,32 + 302,58), in these data only to sex, for hMLH1 protein, was statistically significant (p=0.034). Comparing the different lesions, we observed that for both hMLH1 and hMSH2 protein, the average of positive epithelial cells decreased as the lesion was graded at later stages. The ACs classified without dysplasia or mild dysplasia had the highest average of immunostained cells (hMLH1 = 721.23 + 88.116; hMHS2 = 781.50 + 156.93). The ACs classified as moderate or severe dysplasia had intermediate values (hMLH1 = 532,86 + 197,72; hMHS2 = 611,14 + 172,48) and SSCs of the lower lip had the lowest averages (hMLH1 = 255,03 + 199,47; hMHS2 = 518,38 + 265,68). There was a statistically significant difference between groups (p<0.001). In conclusion, our data support the hypothesis that changes in immunoexpression of these proteins is related to the process of carcinogenesis of the lower lip

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The Oral Epithelial Dysplasia (OED) is the lesion that precedes or co-exists with the Oral Squamous Cell Carcinoma (OSCC), presenting molecular and/or histological similar alterations. The divergences about the malignization potential of OEDs and the role of inflammation in this process make hard the early diagnosis and evaluation of OSCCs aggressiveness. Thus, it became the goal of this study to evaluate the role of inflammation in oral carcinogenesis and tumoral aggressiveness. For this purpose a morphological study was performed in 20 OED cases and 40 OSCC cases to detect the malignization potential of OEDs and the histologic malignancy grading (HMG) of OSCCs, analyzing superficial masses for dismorphism evaluation and the invasive front for evaluation of tumoral growing; and immunohistochemical, using anti-CD8, anti-FOXP3, anti-TGFβ, anti-TNFα and anti-NF-кB antibodies, comparing their with the types lesion, histological degree and intensity of the inflammatory infiltrate. The results were statistically significant for the parameters: cell maturity (p=0,0001), masses presence (p=0,038) and dismorphism (p=0,037), when associated to HMG. To compare the expression of the markers with the types lesion, a significantly higher expression of CD8 (p=0,001) and NF-кB (p=0,002) in the OED, and also a smaller expression of the epithelial TGFβ in the severe OEDs (p=0,011), without significant expression between OSCC degrees. By relating the expression of the studied markers with the inflammatory infiltrate intensity, a positive relation was observed with: inflammatory TNFα(p=0,003), epithelial TNFα and NF-кB (p=0,051 and p=0,004), in OEDs; and with CD8 (p=0,021) and TNFα (p=0,015) in conjunctive OSCCs; and a negative relation with epithelial TNFα (p=0,034) in OSCCs. No significant relation was found between FOXP3 with any of the studied variables. These findings lead to the conclusion that, the study of the invasive front is as important as the study of superficial masses for the evaluation of tumoral aggressiveness; the intensity of the inflammatory infiltrate has no use as a parameter for prognostic evaluation of OSCC in routine exams, but, the molecular events detected in this study may be necessary to give basis for determining the malignant potential in OEDs and aggressiveness in OSCCs

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CDX2 is a recently cloned homeobox gene that encodes an intestine-specific transcription factor, expressed in the nuclei of epithelial cells throughout the intestine, from duodenum to rectum. While expression of CDX2 protein in primary and metastatic colorectal carcinomas has been previously documented, neither the sensitivity nor the specificity of CDX2 expression, as determined by immunohistochemistry, for colorectal adenocarcinoma has been determined. We performed an immunohistochemical survey of 476 tumors with a monoclonal antibody, CDX2-88, including 89 tumors from the colon and duodenum and 95 tumors from other gastrointestinal sites, including the esophagus, stomach, pancreatobiliary system, gastrointestinal carcinoids, and liver. CDX2 was expressed uniformly (that is, in 76-100% of tumor cells) in all but one of the evaluated colorectal and duodenal tumors. High-level expression of CDX2 was also found, however, in mucinous ovarian carcinomas and adenocarcinomas primary to the urinary bladder of which 64% and 100% were positive, respectively. Gastric, gastroesophageal, and pancreatic adenocarcinomas and cholangiocarcinomas all showed similar, heterogeneous patterns of CDX2 expression. Most tumors in each group showed CDX2 expression by a minority of cells, whereas a substantial minority of cases in each group was completely negative and a smaller minority was uniformly positive. Gastrointestinal carcinoids gave similarly varied results, but the majority (58%) was negative. Hepatocellular carcinomas showed no expression of CDX2. Only very rare examples of carcinomas of the genitourinary and gynecologic tracts, breast, lung, and head and neck showed significant levels of CDX2 expression. In this study of primary and metastatic epithelial tumors, uniform CDX2 expression is demonstrated to be an exquisitely sensitive and highly, but incompletely, specific marker of intestinal adenocarcinomas. Compared with villin, a previously described marker of GI adenocarcinomas, CDX2 demonstrated superior sensitivity and comparable specificity. CDX2 expression can be seen, however, in selected non-GI adenocarcinomas such as mucinous ovarian carcinomas and adenocarcinomas of the urinary bladder.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)