913 resultados para small cell carcinoma


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Several randomized phase III studies in advanced stage non-small cell lung cancer (NSCLC) confirmed the superior response rate and progression-free survival of using epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor as first-line therapy compared with chemotherapy in patients with activating EGFR mutations. Despite the need for EGFR mutation tests to guide first-line therapy in East Asian NSCLC, there are no current standard clinical and testing protocols.

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Non-small cell lung carcinoma remains by far the leading cause of cancer-related deaths worldwide. Overexpression of FLIP, which blocks the extrinsic apoptotic pathway by inhibiting caspase-8 activation, has been identified in various cancers. We investigated FLIP and procaspase-8 expression in NSCLC and the effect of HDAC inhibitors on FLIP expression, activation of caspase-8 and drug resistance in NSCLC and normal lung cell line models. Immunohistochemical analysis of cytoplasmic and nuclear FLIP and procaspase-8 protein expression was carried out using a novel digital pathology approach. Both FLIP and procaspase-8 were found to be significantly overexpressed in tumours, and importantly, high cytoplasmic expression of FLIP significantly correlated with shorter overall survival. Treatment with HDAC inhibitors targeting HDAC1-3 downregulated FLIP expression predominantly via post-transcriptional mechanisms, and this resulted in death receptor- and caspase-8-dependent apoptosis in NSCLC cells, but not normal lung cells. In addition, HDAC inhibitors synergized with TRAIL and cisplatin in NSCLC cells in a FLIP- and caspase-8-dependent manner. Thus, FLIP and procaspase-8 are overexpressed in NSCLC, and high cytoplasmic FLIP expression is indicative of poor prognosis. Targeting high FLIP expression using HDAC1-3 selective inhibitors such as entinostat to exploit high procaspase-8 expression in NSCLC has promising therapeutic potential, particularly when used in combination with TRAIL receptor-targeted agents.

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AIM: We investigated tissue biomarkers in non-small cell lung cancer (NSCLC) to find indicators of brain metastasis and peritumoral brain edema.

PATIENTS AND METHODS: Fifty-two cases were studied out of which 26 had corresponding brain metastatic tissue. Clinicopathological characteristics of tumors were correlated with biomarkers of cell adhesion, cell growth, cell cycle and apoptosis regulation that were previously immunohistochemically studied but never analyzed separately according to histological subgroups, gender and smoking history.

RESULTS: Increased collagen XVII in adenocarcinoma (ADC) and increased caspase-9, CD44v6, and decreased cellular apoptosis susceptibility protein (CAS) and Ki-67 in squamous cell carcinoma (SCC) correlated significantly with brain metastasis. Increased β-catenin, E-cadherin and decreased caspase-9 expression in primary SCC, and decreased CD44v6 expression in brain metastatic SCC tissues showed a significant correlation with the extent of peritumoral brain edema. Positive correlation between smoking and biomarker expression could be observed in metastatic ADCs with p16 and caspase-8, while-negative correlation was found in SCC without brain metastasis with caspase-3, and in SCC with brain metastasis with p27.

CONCLUSION: Our results highlight the importance of separate analysis of biomarker expression in histological subtypes of NSCLC.

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Chemotherapies that target thymidylate synthase (TS) continue to see considerable clinical expansion in non-small cell lung cancer (NSCLC). One drawback to TS-targeted therapies is drug resistance and subsequent treatment failure. Novel therapeutic and biomarker-driven strategies are urgently needed. The enzyme deoxyuridine triphosphate nucleotidohydrolase (dUTPase) is reported to protect tumor cells from aberrant misincorporation of uracil during TS inhibition. The goal of this study was to investigate the expression and significance of dUTPase in mediating response to TS-targeted agents in NSCLC. The expression of dUTPase in NSCLC cell lines and clinical specimens was measured by quantitative real-time reverse transcriptase PCR and immunohistochemistry. Using a validated RNA interference approach, dUTPase was effectively silenced in a panel of NSCLC cell lines and response to the fluoropyrimidine fluorodeoxyuridine (FUdR) and the antifolate pemetrexed was analyzed using growth inhibition and clonogenic assays. Apoptosis was analyzed by flow cytometry. Significant variation in the quantity and cellular expression of dUTPase was observed, including clear evidence of overexpression in NSCLC cell line models and tumor specimens at the mRNA and protein level. RNA interference-mediated silencing of dUTPase significantly sensitized NSCLC cells to growth inhibition induced by FUdR and pemetrexed. This sensitization was accompanied by a significant expansion of intracellular dUTP pools and significant decreases in NSCLC cell viability evaluated by clonogenicity and apoptotic analyses. Together, these results strongly suggest that uracil misincorporation is a potent determinant of cytotoxicity to TS inhibition in NSCLC and that inhibition of dUTPase is a mechanism-based therapeutic approach to significantly enhance the efficacy of TS-targeted chemotherapeutic agents.

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Photodynamic therapy (PDT) using a haematoporphyrin derivative (Photogem (R), General Physics Institute and clustes Ltda) as photosensitizer and light emitting diodes (LEDs) as the light source was evaluated in 12 cats with cutaneous squamous cell carcinoma. Lesions were illuminated with LEDs, (300 J/cm for 30 min) 24 h after the administration of the photosensitizer. Clinical responses were classified as complete disappearance of the tumour with total re-epithelialization; partial response (a reduction greater than 50%); and no response (less than 50% reduction). Tumours localized to the pinna treated with one (n = 3) or two (n = 4) applications of PDT yielded no response. Highly invasive tumours of the nose and nasal planum also showed no response, after two treatments (n = 2). A combination of PDT and surgery was performed in three cases. Two cats showed partial response and one complete response with one application of therapy 30 days after nasal surgery. Small and noninfiltrative lesions (n = 3) of the nasal planum showed a PR with one application (n = 2) and a CR with two applications (n = 1). This study shows that PDT using Photogem (R) and LEDs can provide local control of low-grade feline squamous cell carcinoma. The addition of PDT to surgery in more invasive cases may help prevent recurrence.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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OBJECTIVETo determine the current status of the literature regarding the clinical efficacy and complication rates of cryoablation vs radiofrequency ablation in the treatment of small renal tumours.METHODSA review of the literature was conducted. There was no language restriction. Studies were obtained from the following sources: MEDLINE, EMBASE and LILACS.Inclusion criteria were (i) case series design with more than one case reported, (ii) use of cryoablation or radiofrequency ablation, (iii) patients with renal cell carcinoma and, (iv) outcome reported as clinical efficacy.When available, we also quantified the complication rates from each included study.Proportional meta-analysis was performed on both outcomes with a random-effects model. The 95% confidential intervals were also calculated.RESULTSThirty-one case series (20 cryoablation, 11 radiofrequency ablation) met all inclusion criteria.The pooled proportion of clinical efficacy was 89% in cryoablation therapy from a total of 457 cases. There was a statistically significant heterogeneity between these studies showing the inconsistency of clinical and methodological aspects.The pooled proportion of clinical efficacy was 90% in radiofrequency ablation therapy from a total of 426 cases. There was no statistically significant heterogeneity between these studies.There was no statistically significant difference regarding complications rate between cryoablation and radiofrequency ablation.CONCLUSIONSThis review shows that both ablation therapies have similar efficacy and complication rates.There is urgency for performing clinical trials with long-term data to establish which intervention is most suitable for the treatment of small renal masses.

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Objectives: The Head and Neck Squamous Cell Carcinoma (HNSCC) ranks sixth worldwide. The mechanisms of growth, invasion and metastasis of this pathology are extensively studied and generally related to specific variations in signaling pathways like the PI3K-Akt; however most of these competent studies have been performed bidimensionally, which may hide important questions. This study sought to analyze the influence of the microenvironment upon the behavior of HNSCC. Study Design: The status of pAkt, NF-kappa B and Cyclin D1 proteins was accessed through immunofluorescence and western blot methods in HNSCC cell lines originating from tongue, pharynx and metastatic lymph node when submitted to a three-dimensional culture model utilizing a matrix system. A bidimensional culture model (monolayer) was used as control. Results: The HNSCC cell lines cultured three-dimensionally exhibited a growth pattern characterized by small isolated islands, different from the control group. When the three-dimensional model was applied, two of the studied cell lines showed the same expression pattern as the bidimensional model regarding nuclear or cytoplasmatic localization, as well as reduction of all protein levels; however, the cell line originated from tongue, which specially has the epidermal growth factor receptor constitutively activated, demonstrated nuclear translocation of pAkt and also an increase in the levels of Cyclin D1. Conclusions: The results suggest the influence of the microenvironment upon the behavior of HNSCC cells due to the changed expression of proteins related to tumor growth and cellular invasion. Furthermore, intrinsically genetic conditions also played important roles over the cells, despite the culture model employed.

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Background. Previous knowledge of cervical lymph node compromise may be crucial to choose the best treatment strategy in oral squamous cell carcinoma (OSCC). Here we propose a set four genes, whose mRNA expression in the primary tumor predicts nodal status in OSCC, excluding tongue. Material and methods. We identified differentially expressed genes in OSCC with and without compromised lymph nodes using Differential Display RT-PCR. Known genes were chosen to be validated by means of Northern blotting or real time RT-PCR (qRT-PCR). Thereafter we constructed a Nodal Index (NI) using discriminant analysis in a learning set of 35 patients, which was further validated in a second independent group of 20 patients. Results. Of the 63 differentially expressed known genes identified comparing three lymph node positive (pN+) and three negative (pN0) primary tumors, 23 were analyzed by Northern analysis or RT-PCR in 49 primary tumors. Six genes confirmed as differentially expressed were used to construct a NI, as the best set predictive of lymph nodal status, with the final result including four genes. The NI was able to correctly classify 32 of 35 patients comprising the learning group (88.6%; p = 0.009). Casein kinase 1alpha1 and scavenger receptor class B, member 2 were found to be up regulated in pN + group in contrast to small proline-rich protein 2B and Ras-GTPase activating protein SH3 domain-binding protein 2 which were upregulated in the pN0 group. We validated further our NI in an independent set of 20 primary tumors, 11 of them pN0 and nine pN+ with an accuracy of 80.0% (p = 0.012). Conclusions. The NI was an independent predictor of compromised lymph nodes, taking into the consideration tumor size and histological grade. The genes identified here that integrate our "Nodal Index" model are predictive of lymph node metastasis in OSCC.

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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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Background Up-regulation of S100A7 (Psoriasin), a small calcium-binding protein, is associated with the development of several types of carcinomas, but its function and possibility to serve as a diagnostic or prognostic marker have not been fully defined. In order to prepare antibodies to the protein for immunohistochemical studies we produced the recombinant S100A7 protein in E. coli. mRNA extracted from human tracheal tumor tissue which was amplified by RT-PCR to provide the region coding for the S100A7 gene. The amplified fragment was cloned in the vector pCR2.1-TOPO and sub-cloned in the expression vector pAE. The protein rS100A7 (His-tag) was expressed in E. coli BL21::DE3, purified by affinity chromatography on an Ni-NTA column, recovered in the 2.0 to 3.5 mg/mL range in culture medium, and used to produce a rabbit polyclonal antibody anti-rS100A7 protein. The profile of this polyclonal antibody was evaluated in a tissue microarray. Results The rS100A7 (His-tag) protein was homogeneous by SDS-PAGE and mass spectrometry and was used to produce an anti-recombinant S100A7 (His-tag) rabbit serum (polyclonal antibody anti-rS100A7). The molecular weight of rS100A7 (His-tag) protein determined by linear MALDI-TOF-MS was 12,655.91 Da. The theoretical mass calculated for the nonapeptide attached to the amino terminus is 12,653.26 Da (delta 2.65 Da). Immunostaining with the polyclonal anti-rS100A7 protein generated showed reactivity with little or no background staining in head and neck squamous cell carcinoma cells, detecting S100A7 both in nucleus and cytoplasm. Lower levels of S100A7 were detected in non-neoplastic tissue. Conclusions The polyclonal anti-rS100A7 antibody generated here yielded a good signal-to-noise contrast and should be useful for immunohistochemical detection of S100A7 protein. Its potential use for other epithelial lesions besides human larynx squamous cell carcinoma and non-neoplastic larynx should be explored in future.

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Non-small-cell lung cancer (NSCLC) represents the leading cause of cancer death worldwide, and 5-year survival is about 16% for patients diagnosed with advanced lung cancer and about 70-90% when the disease is diagnosed and treated at earlier stages. Treatment of NSCLC is changed in the last years with the introduction of targeted agents, such as gefitinib and erlotinib, that have dramatically changed the natural history of NSCLC patients carrying specific mutations in the EGFR gene, or crizotinib, for patients with the EML4-ALK translocation. However, such patients represent only about 15-20% of all NSCLC patients, and for the remaining individuals conventional chemotherapy represents the standard choice yet, but response rate to thise type of treatment is only about 20%. Development of new drugs and new therapeutic approaches are so needed to improve patients outcome. In this project we aimed to analyse the antitumoral activity of two compounds with the ability to inhibit histone deacethylases (ACS 2 and ACS 33), derived from Valproic Acid and conjugated with H2S, in human cancer cell lines derived from NSCLC tissues. We showed that ACS 2 represents the more promising agent. It showed strong antitumoral and pro-apoptotic activities, by inducing membrane depolarization, cytocrome-c release and caspase 3 and 9 activation. It was able to reduce the invasive capacity of cells, through inhibition of metalloproteinases expression, and to induce a reduced chromatin condensation. This last characteristic is probably responsible for the observed high synergistic activity in combination with cisplatin. In conclusion our results highlight the potential role of the ACS 2 compound as new therapeutic option for NSCLC patients, especially in combination with cisplatin. If validated in in vivo models, this compound should be worthy for phase I clinical trials.

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Proteins of the lysyl oxidase (LOX) family are important modulators of the extracellular matrix. However, they have an important role in the tumour development as well as in tumour progression. To evaluate the diagnostic and prognostic value of the LOX protein in oral and oropharyngeal squamous cell carcinoma (OSCC) we performed QRT-PCR and immunohistochemical analysis on two tissue microarrays (622 tissue samples in total). Significantly higher LOX expression was detected in high grade dysplastic oral mucosa as well as in OSCC when compared to normal oral mucosa (P < 0.001). High LOX expression was correlated with clinical TNM stage (P = 0.020), lymph node metastases for the entire cohort (P < 0.001), as well as in the subgroup of small primary tumours (T1/T2, P < 0.001). Moreover, high LOX expression was correlated with poor overall survival (P = 0.004) and disease specific survival (P = 0.037). In a multivariate analysis, high LOX expression was an independent prognostic factor, predicting unfavourable overall survival. In summary, LOX expression is an independent prognostic biomarker and a predictor of lymph node metastasis in OSCC. Moreover, LOX overexpression may be an early phenomenon in the pathogenesis of OSCC and thus an attractive novel target for chemopreventive and therapeutic strategies.

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Cyclooxygenase-2 (COX-2) inhibitors mediate a systemic antitumor activity via antiangiogenesis and seem to enhance the response of primary tumors to radiation. Radiosensitizing effects of COX-2 inhibition have not been reported for bone metastases. Therefore, the aim of this study was the investigation of the radiosensitizing effects of the selective COX-2 inhibitor celecoxib in secondary bone tumors of a non-small cell lung carcinoma in vivo.

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PURPOSE: The cyclin D1 (CCND1) A870G gene polymorphism is linked to the outcome in patients with resectable non-small cell lung cancer (NSCLC). Here, we investigated the impact of this polymorphism on smoking-induced cancer risk and clinical outcome in patients with NSCLC stages I-IV. METHODS: CCND1 A870G genotype was determined by polymerase chain reaction (PCR) and restriction fragment length polymorphism analysis (RFLP) of DNA extracted from blood. The study included 244 NSCLC patients and 187 healthy control subjects. RESULTS: Patient characteristics were: 70% male, 77% smokers, 43% adenocarcinoma, and 27% squamous cell carcinoma. Eighty-one percent of the patients had stages III-IV disease. Median age at diagnosis was 60 years and median survival was 13 months. Genotype frequencies of patients and controls both conformed to the Hardy Weinberg equilibrium. The GG genotype significantly correlated with a history of heavy smoking (>or=40 py, P=0.02), and patients with this genotype had a significantly higher cigarette consumption than patients with AA/AG genotypes (P=0.007). The GG genotype also significantly correlated with tumor response or stabilization after a platinum-based first-line chemotherapy (P=0.04). Survival analysis revealed no significant differences among the genotypes. CONCLUSION: Evidence was obtained that the CCND1 A870G gene polymorphism modulates smoking-induced lung cancer risk. Further studies are required to explore the underlying molecular mechanisms and to test the value of this gene polymorphism as a predictor for platinum-sensitivity in NSCLC patients.