942 resultados para Carcinoma ductal de mama


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The ability to induce apoptosis is an important marker for cytotoxic antitumor agents. Some natural compounds have been shown to modulate apoptosis pathways that are frequently blocked in human cancers, and therefore, these compounds provide novel opportunities for cancer drug development. Phyllanthus, a plant genus of the family Euphorbiaceae, exhibits multiple pharmacological actions. Of these, Phyllanthus niruri extracts exhibit significant antitumor activity, which is consistent with the traditional medicinal use of this plant. To examine the apoptotic effects of a spray-dried extract of P. niruri (SDEPN), human hepatocellular carcinoma cells (HepG2, Huh-7), colorectal carcinoma cells (Ht29) and keratinocytes (HaCaT) were exposed to the extract for 4, 8 and 24 h. Flow cytometry and caspase-3 immunostaining were used to detect apoptosis, while analysis of variance was applied to identify significant differences between groups (P < 0.05). At all timepoints, the SDEPN induced significantly different cytotoxic effects for HepG2 and Huh-7 cells compared with control cells (P < 0.001). In contrast, the SDEPN had a protective effect on HaCaT cells compared with control cells at all timepoints (P < 0.001). In caspase-3 assays, activation was detected after cell death was induced in Huh-7 and HepG2 cancer cells by the SDEPN. In combination, these results indicate that the SDEPN is selectively toxic towards cancer cell lines, yet is protective towards normal cells.

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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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Laryngeal squamous cell carcinoma is one of the most common malignant neoplasms of the head and neck. In Brazil, laryngeal tumors represent 2% of all cancers and are associated with approximately 3,000 deaths annually. Human papillomavirus (HPV) has been reported to play an important role in the etiology of laryngeal cancer. The aim of the present study was to evaluate the expression of p53, p27, and Mdm2 in laryngeal carcinomas. Sixty-three larynx biopsies were selected for the study, including 9 in situ laryngeal carcinomas, 27 laryngeal carcinomas without metastasis and 27 laryngeal carcinomas with metastasis. Twenty-seven cervical lymph nodes from patients with metastatic lesions were also evaluated. The expression levels of p53, p27, and Mdm2 were assessed by immunohistochemistry using a computer-assisted system. HPV detection and typing were performed using PCR, and the HPV types that were evaluated included HPV 6, 11, 16, 18, 31 and 33. Out of 63 patients, 53 (84.1%) were positive for beta-globin (internal control), and 10 (15.9%) were beta-globin negative and therefore excluded from the evaluation. Thus, 7 (13.2%) out of 53 patients were HPV positive, and 46 (86.8%) out of 53 patients were HPV negative. Statistically significant differences (p < 0.05) in Mdm2 expression levels were observed in the in situ laryngeal carcinoma samples compared with the laryngeal carcinoma samples with metastasis. No statistically significant differences (p > 0.05) in either p53 or p27 expression levels were detected. These findings suggest that Mdm2 may be associated with the invasiveness and aggressiveness of laryngeal carcinomas.

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We show that BJcuL, a lectin purified from Bothrops jararacussu venom, exerts cytotoxic effects to gastric carcinoma cells MKN45 and AGS. This effect was due to the direct interaction with specific glycans on the cells surface and was observed by cell viability decrease, disorganization of actin filaments and apoptosis. In addition, BJcuL was able to reduce tumor cell adhesion to matrigel, what was inhibited by specific carbohydrate or partially inhibited when cells were pre-incubated with matrigel. Our results suggest that BJcuL was able to promote apoptosis in both tumor cells lines and therefore has a prospect for potential use in cancer therapy. (C) 2011 Elsevier Ltd. All rights reserved.

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Trichoepithelioma is a benign neoplasm that shares both clinical and histological features with basal cell carcinoma. It is important to distinguish these neoplasms because they require different clinical behavior and therapeutic planning. Many studies have addressed the use of immunohistochemistry to improve the differential diagnosis of these tumors. These studies present conflicting results when addressing the same markers, probably owing to the small number of basaloid tumors that comprised their studies, which generally did not exceed 50 cases. We built a tissue microarray with 162 trichoepithelioma and 328 basal cell carcinoma biopsies and tested a panel of immune markers composed of CD34, CD10, epithelial membrane antigen, Bcl-2, cytokeratins 15 and 20 and D2-40. The results were analyzed using multiple linear and logistic regression models. This analysis revealed a model that could differentiate trichoepithelioma from basal cell carcinoma in 36% of the cases. The panel of immunohistochemical markers required to differentiate between these tumors was composed of CD10, cytokeratin 15, cytokeratin 20 and D2-40. The results obtained in this work were generated from a large number of biopsies and resulted in the confirmation of overlapping epithelial and stromal immunohistochemical profiles from these basaloid tumors. The results also corroborate the point of view that trichoepithelioma and basal cell carcinoma tumors represent two different points in the differentiation of a single cell type. Despite the use of panels of immune markers, histopathological criteria associated with clinical data certainly remain the best guideline for the differential diagnosis of trichoepithelioma and basal cell carcinoma. Modern Pathology (2012) 25, 1345-1353; doi: 10.1038/modpathol.2012.96; published online 8 June 2012

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Objective Immune responses against differentiated thyroid carcinomas (DTC) have long been recognized. We aimed to investigate the role of immune cell infiltration in the progression of DTC. Design We studied 398 patients 253 with papillary and 13 with follicular thyroid cancers, as well as 132 with nonmalignant tissues. Patients and measurements Immune cell infiltration was identified using CD3, CD4, CD8, CD20, CD68 and FoxP3 immunohistochemical markers. In addition, we assessed colocalization of CD4 and IL-17 to identify Th17 lymphocytic infiltration and colocalization of CD33 and CD11b to identify infiltration of myeloid-derived suppressor cells (MDSC). Results Immune cells infiltrated malignant tissues more often than benign lesions. The presence of chronic lymphocytic thyroiditis (CLT) concurrent to DTC, CD68+, CD4+, CD8+, CD20+, FoxP3+ and Th17 lymphocytes but not MDSCs was associated with clinical and pathological features of lower tumour aggressiveness and a more favourable patient outcome. A log-rank test confirmed an association between concurrent CLT, tumour-associated macrophage infiltration, and CD8+ lymphocytes and an increased in disease-free survival, suggesting that evidence of these immune reactions is associated with a favourable prognosis. Conclusion Our data suggest that the tumour or peri-tumoural microenvironment may act to modify the observed pattern of immune response. Immune cell infiltration and the presence of concurrent CLT helped characterize specific tumour histotypes associated with favourable prognostic features.

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Embryonic carcinoma cells are widely used models for studying the mechanisms of proliferation and differentiation occurring during early embryogenesis. We have now investigated how down-regulation of P2X2 and P2X7 receptor expression by RNA interference (RNAi) affects neural differentiation and phenotype specification of P19 embryonal carcinoma cells. Wild-type P19 embryonal carcinoma cells or cells stably expressing shRNAs targeting P2X2 or P2X7 receptor expression were induced to differentiate into neurons and glial cells in the presence of retinoic acid. Silencing of P2X2 receptor expression along differentiation promoted cell proliferation and an increase in the percentage of cells expressing glial-specific GFAP, while the presence of beta-3 tubulin-positive cells diminished at the same time. Proliferation induction in the presence of stable anti-P2X2 receptor RNAi points at a mechanism where glial proliferation is favored over growth arrest of progenitor cells which would allow neuronal maturation. Differently from the P2X2 receptor, inhibition of P2X7 receptor expression during neural differentiation of P19 cells resulted in a decrease in cell proliferation and GFAP expression, suggesting the need of functional P2X7 receptors for the progress of gliogenesis. The results obtained in this study indicate the importance of purinergic signaling for cell fate determination during neural differentiation, with P2X2 and P2X7 receptors promoting neurogenesis and gliogenesis, respectively. The shRNAs down-regulating P2X2 or P2X7 receptor gene expression, developed during this work, present useful tools for studying mechanisms of neural differentiation in other stem cell models. (C) 2012 ISDN. Published by Elsevier Ltd. All rights reserved.

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Aims: To evaluate the associations of excision repair cross complementing-group 1 (ERCC1) (DNA repair protein) (G19007A) polymorphism, methylation and immunohistochemical expression with epidemiological and clinicopathological factors and with overall survival in head and neck squamous cell carcinoma (HNSCC) patients. Methods and results: The study group comprised 84 patients with HNSCC who underwent surgery and adjuvant radiotherapy without chemotherapy. Bivariate and multivariate analyses were used. The allele A genotype variant was observed in 79.8% of the samples, GG in 20.2%, GA in 28.6% and AA in 51.2%. Individuals aged more than 45 years had a higher prevalence of the allelic A variant and a high (83.3%) immunohistochemical expression of ERCC1 protein [odds ratio (OR) = 4.86, 95% confidence interval (CI): 1.2-19.7, P = 0.027], which was also high in patients with advanced stage (OR= 5.04, 95% CI: 1.07-23.7, P = 0.041). Methylated status was found in 51.2% of the samples, and was higher in patients who did not present distant metastasis (OR = 6.67, 95% CI: 1.40-33.33, P = 0.019) and in patients with advanced stage (OR = 5.04, 95% CI: 1.07-23.7, P = 0.041). At 2 and 5 years, overall survival was 55% and 36%, respectively (median = 30 months). Conclusion: Our findings may reflect a high rate of DNA repair due to frequent tissue injury during the lifetime of these individuals, and also more advanced disease presentation in this population with worse prognosis.

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Abstract Background To test if the expression of Smad1-8 mRNAs were predictive of survival in patients with oral squamous cell carcinoma (SCC). Patients and Methods We analyzed, prospectively, the expression of Smad1-8, by means of Ribonuclease Protection Assay in 48 primary, operable, oral SCC. In addition, 21 larynx, 10 oropharynx and 4 hypopharynx SCC and 65 matched adjacent mucosa, available for study, were also included. For survival analysis, patients were categorized as positive or negative for each Smad, according to median mRNA expression. We also performed real-time quantitative PCR (QRTPCR) to asses the pattern of TGFβ1, TGFβ2, TGFβ3 in oral SCC. Results Our results showed that Smad2 and Smad6 mRNA expression were both associated with survival in Oral SCC patients. Cox Multivariate analysis revealed that Smad6 positivity and Smad2 negativity were both predictive of good prognosis for oral SCC patients, independent of lymph nodal status (P = 0.003 and P = 0.029, respectively). In addition, simultaneously Smad2- and Smad6+ oral SCC group of patients did not reach median overall survival (mOS) whereas the mOS of Smad2+/Smad6- subgroup was 11.6 months (P = 0.004, univariate analysis). Regarding to TGFβ isoforms, we found that Smad2 mRNA and TGFβ1 mRNA were inversely correlated (p = 0.05, R = -0.33), and that seven of the eight TGFβ1+ patients were Smad2-. In larynx SCC, Smad7- patients did not reach mOS whereas mOS of Smad7+ patients were only 7.0 months (P = 0.04). No other correlations were found among Smad expression, clinico-pathological characteristics and survival in oral, larynx, hypopharynx, oropharynx or the entire head and neck SCC population. Conclusion Smad6 together with Smad2 may be prognostic factors, independent of nodal status in oral SCC after curative resection. The underlying mechanism which involves aberrant TGFβ signaling should be better clarified in the future.

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Abstract Background Squamous cell carcinoma (SCC) of the skin of the trunk and extremities may present lymph node metastasis with difficult disease control and poor survival. The purpose of this study was to identify risk factors for lymph node metastasis and outcome. Patients/Methods Retrospective review of 57 patients with locally advanced SCC of the trunk and extremities was performed and several clinical variables including age, gender, ethnicity, previously injured skin (burns, scars, ulcers and others), patient origin (rural or urban), anatomic site and treatment were studied. Results Fifteen patients presented with previous skin lesions. Thirty-six were classified as T3 tumors and 21 as T4; 46 were N0, and 11, N1. Eleven N0 patients presented lymph node metastasis during follow up. Univariate analysis identified previous skin lesions (ulcers and scars) as risk factor for lymph node metastasis (p = 0.047). Better survival was demonstrated for T3 (p = 0.018) classification. N0 patients who presented lymph node metastasis during follow up (submitted to lymphadenectomy) had similar survival to patients without lymph node recurrence (p = 0.219). Conclusion Local advanced tumors are at risk of lymph node metastasis. Increased risk is associated to previous lesions at tumor site. T4 classification have worse prognosis. Lymph node recurrences in N0 patients, once treated, did not affect survival. For these patients, we propose close follow up and prompt treatment of lymph node metastasis. These results do not support indication for elective lymphadenectomy or sentinel node mapping. Further prospective studies must address this issue.

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An 84-year-old woman underwent hysterectomy due to a friable endometrial mass infiltrating almost half way through the myometrial wall. The tumor consisted of papillary structures with thin fibrovascular cores covered by several layers of pleomorphic cells. The deeply located neoplastic cells were ovoid with a pale eosinophilic cytoplasm resembling urothelial cells. A diagnosis of papillary squamous cell carcinoma of the endometrium with transitional cell differentiation was made. Although she recovered well after surgery, she died one year later because of disseminated disease. In an attempt to obtain new insights into the physiopathology of this very rare tumor, an immunohistochemical panel with 32 markers was performed. The neoplastic cells were positive for cytokeratin 5, vimentin, p63, p21, VEGF, Ki67, BAG1, and bcl-2. The expression of BAG-1 and bcl-2 may suggest that anti-apoptotic stimuli are preponderant in this neoplasm.

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Background Human homeobox genes encode nuclear proteins that act as transcription factors involved in the control of differentiation and proliferation. Currently, the role of these genes in development and tumor progression has been extensively studied. Recently, increased expression of HOXB7 homeobox gene (HOXB7) in pancreatic ductal adenocarcinomas (PDAC) was shown to correlate with an invasive phenotype, lymph node metastasis and worse survival outcomes, but no influence on cell proliferation or viability was detected. In the present study, the effects arising from the knockdown of HOXB7 in PDAC cell lines was investigated. Methods Real time quantitative PCR (qRT-PCR) (Taqman) was employed to assess HOXB7 mRNA expression in 29 PDAC, 6 metastatic tissues, 24 peritumoral tissues and two PDAC cell lines. siRNA was used to knockdown HOXB7 mRNA in the cell lines and its consequences on apoptosis rate and cell proliferation were measured by flow cytometry and MTT assay respectively. Results Overexpression of HOXB7 mRNA was observed in the tumoral tissues and in the cell lines MIA PaCa-2 and Capan-1. HOXB7 knockdown elicited (1) an increase in the expression of the pro-apoptotic proteins BAX and BAD in both cell lines; (2) a decrease in the expression of the anti-apoptotic protein BCL-2 and in cyclin D1 and an increase in the number of apoptotic cells in the MIA PaCa-2 cell line; (3) accumulation of cell in sub-G1 phase in both cell lines; (4) the modulation of several biological processes, especially in MIA PaCa-2, such as proteasomal ubiquitin-dependent catabolic process and cell cycle. Conclusion The present study confirms the overexpression of HOXB7 mRNA expression in PDAC and demonstrates that decreasing its protein level by siRNA could significantly increase apoptosis and modulate several biological processes. HOXB7 might be a promising target for future therapies.

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Background: Squamous cell carcinoma (SCC) is one of the most common human cancers worldwide. In SCC, tumour development is accompanied by an immune response that leads to massive tumour infiltration by inflammatory cells, and consequently, local and systemic production of cytokines, chemokines and other mediators. Studies in both humans and animal models indicate that imbalances in these inflammatory mediators are associated with cancer development. Methods: We used a multistage model of SCC to examine the involvement of elastase (ELA), myeloperoxidase (MPO), nitric oxide (NO), cytokines (IL-6, IL-10, IL-13, IL-17, TGF-β and TNF-α), and neutrophils and macrophages in tumour development. ELA and MPO activity and NO, IL-10, IL −17, TNF-α and TGF-β levels were increased in the precancerous microenvironment. Results: ELA and MPO activity and NO, IL-10, IL −17, TNF-α and TGF-β levels were increased in the precancerous microenvironment. Significantly higher levels of IL-6 and lower levels of IL-10 were detected at 4 weeks following 7,12-Dimethylbenz(a)anthracene (DMBA) treatment. Similar levels of IL-13 were detected in the precancerous microenvironment compared with control tissue. We identified significant increases in the number of GR-1+ neutrophils and F4/80+/GR-1- infiltrating cells in tissues at 4 and 8 weeks following treatment and a higher percentage of tumour-associated macrophages (TAM) expressing both GR-1 and F4/80, an activated phenotype, at 16 weeks. We found a significant correlation between levels of IL-10, IL-17, ELA, and activated TAMs and the lesions. Additionally, neutrophil infiltrate was positively correlated with MPO and NO levels in the lesions. Conclusion: Our results indicate an imbalance of inflammatory mediators in precancerous SCC caused by neutrophils and macrophages and culminating in pro-tumour local tissue alterations.

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Isolated splenic metastasis from lung cancer is a very rare occurrence with only a few reports available. Here, we report the case of a 82-year-old male who underwent a bilobectomy for a lung squamous cell carcinoma and 16 months later developed an isolated splenic metastasis. Additionally, previous reports are reviewed and discussed.

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A mucinous tubular and spindle cell carcinoma (MTSCC) is a rare and recently described kidney neoplasm with distal nephron differentiation. It can affect patients of all ages and is more prevalent among women. In this case report, we present a 50-year-old woman who had a renal mass, which was accidently discovered during an investigation for chronic anemia. The final diagnosis of MTSCC was made after the lesion was removed and a pathology work-up was performed. The clinical, pathological and imaging findings of this rare neoplasm are described in this report.