145 resultados para radical superóxido


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Objective: Bronchial typical carcinoid tumors are tow-grade malignancies. However, metastases are diagnosed in some patients. Predicting the individual risk of these metastases to determine patients eligible for a radical lymphadenectomy and patients to be followed-up because of distant metastasis risk is relevant. Our objective was to screen for predictive criteria of bronchial typical carcinoid tumor aggressiveness based on a logistic regression model using clinical, pathological and biomolecular data. Methods: A multicenter retrospective cohort study, including 330 consecutive patients operated on for bronchial typical carcinoid tumors and followed-up during a period more than 10 years in two university hospitals was performed. Selected data to predict the individual risk for both nodal and distant metastasis were: age, gender, TNM staging, tumor diameter and location (central/peripheral), tumor immunostaining index of p53 and Ki67, Bcl2 and the extracellular density of neoformed microvessels and of collagen/elastic extracellular fibers. Results: Nodal and distant metastasis incidence was 11% and 5%, respectively. Univariate analysis identified all the studied biomarkers as related to nodal metastasis. Multivariate analysis identified a predictive variable for nodal metastasis: neo angiogenesis, quantified by the neoformed pathological microvessels density. Distant metastasis was related to mate gender. Discussion: Predictive models based on clinical and biomolecular data could be used to predict individual risk for metastasis. Patients under a high individual risk for lymph node metastasis should be considered as candidates to mediastinal lymphadenectomy. Those under a high risk of distant metastasis should be followed-up as having an aggressive disease. Conclusion: Individual risk prediction of bronchial typical carcinoid tumor metastasis for patients operated on can be calculated in function of biomolecular data. Prediction models can detect high-risk patients and help surgeons to identify patients requiring radical lymphadenectomy and help oncologists to identify those as having an aggressive disease requiring prolonged follow-up. (C) 2008 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

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Multimodality treatment of rectal cancer, with the combination of radiation therapy, chemotherapy, and surgery has become the preferred approach to locally advanced rectal cancer The use of neoadjuvant chemoradiation therapy (CRT) has resulted in reduced toxicity rates, significant tumor down-sizing and downstaging, better chance of sphincter preservation, and improved functional results A proportion of patients treated with neoadjuvant CRT may ultimately develop complete clinical response Management of these patients with complete clinical response remains controversial and approaches including radical resection, transanal local excision, and observation alone without immediate surgery have been proposed The use of strict selection criteria of patients after neoadjuvant CRT has resulted in excellent long-term results with no oncological compromise after observation alone in patients with complete clinical response Recurrences are detectable by clinical assessment and frequently amenable to salvage procedures

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BACKGROUND. Integrins and other adhesion molecules are essential for maintaining the epithelial phenotype. Some studies have reported correlations between abnormalities in their expression and carcinogenesis, but their role in prostate cancer is unclear. Our aim was to study the expression profile of integrins in surgical specimens of prostate cancer and associate their expression patterns with patient outcomes. METHODS. We selected 111 patients with localized prostate cancer who had undergone radical prostatectomy. Of these patients, 60 had no tumor recurrence after a median follow-up of 123 months. Integrin expression was evaluated by immunohistochemistry in a tissue microarray containing two tumor samples per patient. A semiquantitative analysis was employed. We measured the association between the expression of eight integrins and tumor recurrence. RESULTS. Multivariate analysis showed that expression of alpha 3 and alpha 3 beta 1 was related to worse outcome. When alpha 3 expression was strong and alpha 3 beta 1 expression was positive, the odds of recurrence were 3.0- and 2.5-fold higher, respectively. Only 19% and 28% of patients were recurrence-free in a mean period of 123 months of follow up when their tumors showed strong alpha 3 or positive alpha 3 beta 1 immuno-expression, respectively. CONCLUSIONS. We have shown that the expression of integrin alpha 3 beta 1 was independently associated with tumor recurrence after radical prostatectomy, suggesting that this integrin is a potential prognostic marker. Prostate 70: 1189-1195, 2010. (C) 2010 Wiley-Liss, Inc.

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Background Intestinal and pancreaticobiliary types of Vater`s ampulla adenocarcinoma have been considered as having different biologic behavior and prognosis. The aim of the present study was to determine the best immunohistochemical panel for tumor classification and to analyze the survival of patients having these histological types of adenocarcinoma. Method Ninety-seven resected ampullary adenocarcinomas were histologically classified, and the prognosis factors were analyzed. The expression of MUC1, MUC2, MUC5AC, MUC6, CK7, CK17, CK20, CD10, and CDX2 was evaluated by using immunohistochemistry. Results Forty-three Vater`s ampulla carcinomas were histologically classified as intestinal type, 47 as pancreaticobiliary, and seven as other types. The intestinal type had a significantly higher expression of MUC2 (74.4% vs. 23.4%), CK20 (76.7% vs. 29.8%), CDX2 (86% vs. 21.3%), and CD10 (81.4% vs. 51.1%), while MUC1 (53.5% vs. 82.9%) and CK7 (79.1% vs. 95.7%) were higher in pancreatobiliary adenocarcinomas. The most accurate markers for immunohistochemical classification were CDX2, MUC1, and MUC2. Survival was significantly affected by pancreaticobiliary type (p=0.021), but only lymph node metastasis, lymphatic invasion, and stage were independent risk factors for survival in a multivariate analysis. Conclusion The immunohistochemical expression of CDX2, MUC1, and MUC2 allows a reproducible classification of ampullary carcinomas. Although carcinomas of the intestinal type showed better survival in the univariate analysis, neither histological classification nor immunohistochemistry were independent predictors of poor prognosis.

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Objectives: E-cadherin and beta-catenin are adhesion molecules responsible for the maintenance of normal epithelial cell phenotype. A disturbance in epithelial cell adhesion, which leads to a more invasive and metastatic phenotype, is a hallmark of tumor progression. Several immunohistochemical studies have reported a strong correlation between loss of their expression to higher stage and grade in prostate carcinoma, but their influence in metastatic process is not yet known. The aim of this study is to verify the role of adhesion molecules in the progression of prostate cancer (PC), assessing the expression of E-cadherin and beta-catenin in bone metastasis. Materials and Methods: Twenty-eight bone metastases of prostate carcinoma were submitted to immunohistochemistry analysis for E-cadherin and beta-catenin expression. In 6 patients, we were able to assess the expression of the adhesion molecules in the primary tumors and their respective metastases. The definition of normal expression for both antibodies was strong and diffuse expression in more than 70% of tumor cells. Results: In bone metastases, there was loss of expression of E-cadherin and beta-catenin in 86% and 82%, respectively. Among the primary tumors, E-cadherin and beta-catenin expression was normal in 83% and 50% cases, respectively. Considering the 6 patients with paired primary and bone metastasis, we found loss of expression for both E-cadherin and beta-catenin in most of the cases. Conclusions: Comparing primary PC and its metastasis, we showed persistent loss of E-cadherin and beta-catenin expression. This phenomenon may be related to metastatic potential in PC, because we have shown underexpression for E-cadherin and beta-catenin in 86% and 82% of bone metastases.

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Purpose: We tested whether the combination of 4 established cell cycle regulators (p53, pRB, p21 and p27) could improve the ability to predict clinical outcomes in a large multi-institutional collaboration of patients with pT3-4N0 or pTany Npositive urothelial carcinoma of the bladder. We also assessed whether the combination of molecular markers is superior to any individual biomarker. Materials and Methods: The study comprised 692 patients with pT3-4N0 or pTany Npositive urothelial carcinoma of the bladder treated with radical cystectomy and bilateral lymphadenectomy (median followup 5.3 years). Scoring was performed using advanced cell imaging and color detection software. The base model incorporated patient age, gender, stage, grade, lymphovascular invasion, number of lymph nodes removed, number of positive lymph nodes, concomitant carcinoma in situ and adjuvant chemotherapy. Results: Individual molecular markers did not improve the predictive accuracy for disease recurrence and cancer specific mortality. Combination of all 4 molecular markers into number of altered molecular markers resulted in significantly 1 higher predictive accuracy than any single biomarker (p < 0.001.). Moreover addition of number of altered molecular markers to the base model significantly improved the predictive accuracy for disease recurrence (3.9%, p < 0.001) and cancer specific mortality (4.3%, p < 0.001). Addition of number of altered molecular markers retained statistical significance for improving the prediction of clinical outcomes in the subgroup of patients with pT3N0 (280), pT4N0 (83) and pTany Npositive (329) disease (p < 0.001). Conclusions: While the status of individual molecular markers does not add sufficient value to outcome prediction in patients with advanced urothelial carcinoma of the bladder, combinations of molecular markers may improve molecular staging, prognostication and possibly prediction of response to therapy.

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Background and Objectives: Some authors states that the removal of lymph node would only contribute towards assessing the lymph node status and regional disease control, without any benefit for the patients` survival. The aim of this paper was to assess the influence of the number of surgically dissected pelvic lymph nodes (PLN) on disease-free Survival. Methods: Retrospective cohort study on 42 women presenting squamous cell carcinoma (SCC) of the uterine cervix, with metastases in PLN treated by radical surgery. The Cox model was used to identify risk factors for recurrence. The model variables were adjusted for treatment-related factors (year of treatment, surgical margins and postoperative radiotherapy). The cutoff value for classifying the lymphadenectomy as comprehensive (15 PLN or more) or non-comprehensive (<15 PLN) was determined from analysis of the ROC curve. Results: Fourteen recurrences (32.6%) were recorded: three pelvic, eight distant, two both pelvic and distant, and one at an unknown location. The following risk factors for recurrence were identified: invasion of the deep third of the cervix and number of dissected lymph nodes <15. Conclusions: Deep invasion and non-comprehensive pelvic lymphadenectomy are possible risk factors for recurrence of SCC of the uterine cervix with metastases in PLN. J. Surg. Oncol. 2009;100:252-257. (C) 2009 Wiley-Liss, Inc.

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Introduction: Hyaluronidases (HAases) are enzymes related to cancer progression. Isoforms of HAases have been described as products of alternative splicing responsible for differences in enzyme activity. The heterogeneity of HAase expression has been identified in tumors and could be related to the differences in their biological behavior. Methods: Thirty-seven patients subjected to radical prostatectomy for prostate cancer were divided into 2 groups for the analyses: Low (<= 6-18) and high (>= 7-19) Gleason score and tumor behavior; recurrence 15 and nonrecurrence 22, mean follow-up 52.6 months. Conclusion: A profile of HAase related to low Gleason score and non-tumor recurrence was characterized by expression of HYAL3-v1, HYAL1-v3, and HYAL3-v2. More studies should be made in order to confirm with larger series. (C) 2009 Elsevier Inc. All rights reserved.

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Tentorial meningiomas account for 2% to 3% of all intracranial meningiomas. The authors present their experience with posterior fossa tentorial meningiomas, and discuss the main features, which influence approaches and complications of the different surgical techniques. Twenty-four patients had meningiomas localized predominantly in posterior fossa. Their historical records and radiologic examinations were reviewed in accordance with Simpson`s classification. The extension of tumor removal was Simpson grade I in 12 patients (50%), grade II in 12 patients (50%), and grades III and IV in none of the patients. In 22 patients (91.66%), the meningioma was classified as grade I and in 2 cases (8.33%) classified as grade 11 (atypical meningioma). The combined supra/infiratentorial was employed in 12 cases, and complete resections were most common with this approach compared with retrosigmoid technique. Postoperative complications occurred in 10 patients (41.6%) with major deficits in 3 patients (12.5%). The authors believe that careful preoperative choice of the surgical approach should be based Oil tumor location and extension. It is then possible to achieve the best radical microsurgical tumor resection, avoiding additional injury to neurovascular structures.

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Purpose: To determine the incidence of overestimation of Gleason score (GS) in extended prostate biopsy, and consequently circumventing unnecessary aggressive treatment. Methods and Materials: This is a retrospective study of 464 patients who underwent prostate biopsy and radical prostatectomy between January 2001 and November 2007. The GS from biopsy and radical prostatectomy were compared. The incidence of overestimation of GS in biopsies and tumor volume were studied. Multivariate analysis was applied to find parameters that predict upgrading the GS in prostate biopsy. Results: The exact agreement of GS between prostate biopsy and radical prostatectomy occurred in 56.9% of cases. In 29.1% cases it was underestimated, and it was overestimated in 14%. One hundred and six (22.8%) patients received a diagnosis of high GS (8, 9, or 10) in a prostate biopsy. In 29.2% of cases, the definitive Gleason Score was 7 or lower. In cases in which GS was overestimated in the biopsy, tumors were significantly smaller. In multivariate analysis, the total percentage of tumor was the only independent factor in overestimation of GS. Tumors occupying less than 33% of cores had a 5.6-fold greater chance of being overestimated. Conclusion: In the extended biopsy era and after the International Society of Urological Pathology consensus on G, almost one third of tumors considered to have high GS at the biopsy may be intermediate-risk cancers. In that condition, tumors are smaller in biopsy. This should be remembered by professionals involved with prostate cancer to avoid overtreatment and undesirable side effects. (c) 2009 Elsevier Inc.

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Excessive free-radical production due to various bacterial components released during bacterial infection has been linked to cell death and tissue injury. Peroxynitrite is a highly reactive oxidant produced by the combination of nitric oxide (NO) and superoxide anion, which has been implicated in cell death and tissue injury in various forms of critical illness. Pharmacological decomposition of peroxynitrite may represent a potential therapeutic approach in diseases associated with the overproduction of NO and superoxide. In the present study, we tested the effect of a potent peroxynitrite decomposition catalyst in murine models of endotoxemia and sepsis. Mice were injected i.p. with LPS 40 mg/kg with or without FP15 [Fe(III) tetrakis-2-(N-triethylene glycol monomethyl ether) pyridyl porphyrin] (0.1, 0.3, 1, 3, or 10 mg/kg per hour). Mice were killed 12 h later, followed by the harvesting of samples from the lung, liver, and gut for malondialdehyde and myeloperoxidase measurements. In other subsets of animals, blood samples were obtained by cardiac puncture at 1.5, 4, and 8 h after LPS administration for cytokine (TNF-alpha, IL-1 beta, and IL-10), nitrite/nitrate, alanine aminotransferase, and blood urea nitrogen measurements. Endotoxemic animals showed an increase in survival from 25% to 80% at the FP15 doses of 0.3 and 1 mg/kg per hour. The same dose of FP15 had no effect on plasma levels of nitrite/nitrate. There was a reduction in liver and lung malondialdehyde in the endotoxemic animals pretreated with FP15, as well as in hepatic myeloperoxidase and biochemical markers of liver and kidney damage (alanine aminotransferase and blood urea nitrogen). In a bacterial model of sepsis induced by cecal ligation and puncture, FP15 treatment (0.3 mg/kg per day) significantly protected against mortality. The current data support the view that peroxynitrite is a critical factor mediating liver, gut, and lung injury in endotoxemia and septic shock: its pharmacological neutralization may be of therapeutic benefit.

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Context.-Studies analyzing the concordance of biopsy and radical prostatectomy (RP) Gleason scores have limitations. Some included 2 or more centers, used historical controls from the early prostate specific antigen era or lacked a clear definition of the biopsy schemes. Furthermore, most did not control the results for prostate volume. Objective.-To confirm whether prediction of RP Gleason score can be optimized by taking more biopsy cores in a contemporary series of patients, with pathologic samples analyzed by the same pathologist, and controlling these results for prostate volume. Design.-The study comprised a retrospective case-control analysis of 393 patients with prostate cancer treated with RP. Patients were divided into 3 groups: those in group 1 underwent a 6-core biopsy; group 2, an 8-core biopsy; and group 3, a 10 or more-core biopsy. Concordance rates between biopsy and RP Gleason scores, as well as the rates of undergrading and overgrading, were determined for each biopsy scheme. Results.-Concordance rates were 60.9%, 58.3%, and 64.6% for patients from groups 1, 2, and 3, respectively (P = .18). When we analyzed patients with prostate volumes of less than 50 cm(3), concordance rates were 58.3%, 58.3%, and 65.1% for each group, respectively (P = .03). Among patients with prostate volumes of 50 cm3 or more, concordance rates were 70%, 58.1%, and 63.6%, respectively (P = .66). Conclusions.-Taking 10 or more cores can improve the prediction of RP Gleason score in patients with prostate volumes of less than 50 cm3. For patients with prostate volumes of 50 cm3 or more, increasing the biopsy cores to 10 or more did not improve prediction of RP Gleason score.

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Objective: MicroRNAs (miRNAs) are small noncoding regulatory RNAs (19-25 nucleotides) that play a major role in regulation of gene expression. They are responsible for the control of fundamental cellular processes that has been reported to be involved in human tumorigenesis. The characterization of miRNA profiles in human tumors is crucial for the understanding of carcinogenesis processes, finding of new tumor markers, and discovering of specific targets for the development of innovative therapies. The aim of this study is to find miRNAs involved in prostate cancer progression comparing the profile of miRNA expressed by localized high grade carcinoma and bone metastasis. Material and methods: Two groups of tumors where submitted to analyses. The first is characterized by 18 patients who underwent radical prostatectomy for treatment of localized high grade prostate carcinoma (PC) with mean Gleason score 8.6, all staged pT3. The second group is composed of 4 patients with metastatic, androgen-independent prostate carcinoma, and 2 PC cell lines. LNCaP derived from a metastatic PC to a lymph node, and another derived from an obstructive, androgen-independent PC (PcBRA1). Expression analysis of 14 miRNAs was carried out using quantitative RT-PCR. Results: miR-let7c, miR-100, and miR-218 were significantly overexpressed by all localized high GS, pT3 PC in comparison with metastatic carcinoma. (35.065 vs. 0.996 P < 0.001), (55.550 vs. 8.314, P = 0.010), and (33.549 vs. 2.748, P = 0.001), respectively. Conclusion: We hypothesize that miR-let7c, miR-100, and miR-218 may be involved in the process of metastasization of PC, and their role as controllers of the expression of RAS, c-myc, Laminin 5 beta 3, THAP2, SMARCA5, and BAZ2A should be matter of additional studies. (C) 2011 Elsevier Inc. All rights reserved.

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Reactive oxygen species oxidize proteins and modulate the proteasomal system in muscle-wasting cancer cachexia. On day 5 (D5), day 10 (D10), and day 14 (D14) after tumor implantation, skeletal muscle was evaluated. Carbonylated proteins and thiobarbituric acid reactive substances were measured. Chemiluminescence was employed for lipid hydroperoxide estimation. Glutathione, superoxide dismutase, and total radical antioxidant capacity were evaluated. The proteasomal system was assessed by mRNA atrogin-1 expression. Increased muscle wasting, lipid hydroperoxide, and superoxide dismutase, and decreased glutathione levels and total radical antioxidant capacity, were found on D5 in accordance with increased mRNA atrogin-1 expression. All parameters were significantly modified in animals treated with alpha-tocopherol. The elevation in aldehylde levels and carbonylated proteins observed on D10 were reversed by cc-tocopherol treatment. Oxidative stress may trigger signal transduction of the proteasomal system and cause protein oxidation. These pathways may be associated with the mechanism of muscle wasting that occurs in cancer cachexia. Muscle Nerve 42: 950-958, 2010

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Object. The goal of this paper is to analyze the extension and relationships of glomus jugulare tumor with the temporal bone and the results of its surgical treatment aiming at preservation of the facial nerve. Based on the tumor extension and its relationships with the facial nerve, new criteria to be used in the selection of different surgical approaches are proposed. Methods. Between December 1997 and December 2007, 34 patients (22 female and 12 male) with glomus jugulare tumors were treated. Their mean age was 48 years. The mean follow-up was 52.5 months. Clinical findings included hearing loss in 88%, swallowing disturbance in 50%, and facial nerve palsy in 41%. Magnetic resonance imaging demonstrated a mass in the jugular foramen in all cases, a mass in the middle ear in 97%, a cervical mass in 85%, and an intradural mass in 41%. The tumor was supplied by the external carotid artery in all cases, the internal carotid artery in 44%, and the vertebral artery in 32%. Preoperative embolization was performed in 15 cases. The approach was tailored to each patient, and 4 types of approaches were designed. The infralabyrinthine retrofacial approach (Type A) was used in 32.5%; infralabyrinthine pre- and retrofacial approach without occlusion of the external acoustic meatus (Type B) in 20.5%; infralabyrinthine pre- and retrofacial approach with occlusion of the external acoustic meatus (Type C) in 41 W. and the infralabyrinthine approach with transposition of the facial nerve and removal of the middle ear structures (Type D) in 6% of the patients. Results. Radical removal was achieved in 91% of the cases and partial removal in 9%. Among 20 patients without preoperative facial nerve dysfunction, the nerve was kept in anatomical position in 19 (95%), and facial nerve function was normal during the immediate postoperative period in 17 (85%). Six patients (17.6%) had a new lower cranial nerve deficit, but recovery of swallowing function was adequate in all cases. Voice disturbance remained in all 6 cases. Cerebrospinal fluid leakage occurred in 6 patients (17.6%), with no need for reoperation in any of them. One patient died in the postoperative period due to pulmonary complications. The global recovery, based on the Karnofsky Performance Scale (KPS), was 100% in 15% of the patients, 90% in 45%, 80% in 33%, and 70% in 6%. Conclusions. Radical removal of glomus jugulare tumor can be achieved without anterior transposition of the facial nerve. The extension of dissection, however, should be tailored to each case based on tumor blood supply, preoperative symptoms, and tumor extension. The operative field provided by the retrofacial infralabyrinthine approach, or the pre- and retrofacial approaches. with or without Closure of the external acoustic meatus, allows a wide exposure of the jugular foramen area. Global functional recovery based on the KPS is acceptable in 94% of the patients. (DOI: 10.3171/2008.10.JNS08612)