996 resultados para THYROID-CARCINOMA


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Objectives: To examine the effects of triiodothyronine (T3), 17β-estradiol (E2), and tamoxifen (TAM) on transforming growth factor (TGF)-α gene expression in primary breast cancer cell cultures and interactions between the different treatments. Methods and results: Patients included in the study (no.=12) had been newly diagnosed with breast cancer. Fresh human breast carcinoma tissue was cut into 0.3-mm slices. These slices were placed in six 35-mm dishes on 2-ml organ culture medium. Dishes received the following treatments: dish 1: ethanol; dish 2: T3; dish 3: T3+TAM; dish 4: TAM; dish 5: E2; dish 6: E2+TAM. TGF-α mRNA content was normalized to glyceraldehyde-3-phosphate dehydrogenase mRNA levels. All tissues included in this study were positive for estrogen receptor (ER) and thyroid hormone receptor expression. Treatment with T3 for 48 h significantly increased TGF-α mRNA levels compared to controls (15-fold), and concomitant treatment with TAM reduced expression to 3.4-fold compared to controls. When only TAM was added to the culture medium, TGF-α mRNA expression increased 5.3-fold, significantly higher than with all other treatment modalities. Conclusion: We demonstrate that TGF-α mRNA expression is more efficiently upregulated by T3 than E2. Concomitant treatment with TAM had a mitigating effect on the T3 effect, while E2 induced TGF-α upregulation. Our findings show some similarities between primary culture and breast cancer cell lines, but also some important differences: a) induction of TGF-α, a mitogenic protein, by TAM; b) a differential effect of TAM that may depend on relative expression of ER α and β; and c) supraphysiological doses of T3 may induce mitogenic signals in breast cancer tissue under conditions of low circulating E2. ©2008, Editrice Kurtis.

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A decreased radioiodine uptake is frequently detected in differentiated thyroid carcinomas (DTC) and is associated with high recurrence rate and reduced survival. We investigated the correlation between NIS mRNA expression levels in the primary tumor and patient outcome using a quantitative real-time RT-PCR method. NIS expression was decreased in 17 DTC (21.04 +/- 39.66 pg Eq) compared to four autoimune thyroid disease (180.51 +/- 92.63 pg Eq) and 14 normal tissues (75.71 +/- 66.98 pg Eq) (p < 0.0001). The 17 thyroid differentiated carcinoma patients were submitted to surgery complemented by radioiodine ablation and had at least 24 months of follow-up, under levothyroxine continued suppressive therapy. According to their outcome, we could characterize a group of papillary carcinoma patients with aggressive carcinomas, whose NIS mRNA levels were markedly lower than a group with non-aggressive carcinomas (0.62 +/- 0.79 versus 54.87 +/- 53.79: p < 0.005). We suggest that the quantification of NIS mRNA relative levels in the primary tumor may predict poor outcome. (C) 2003 Elsevier Ireland Ltd. All rights reserved.

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It is believed that epigenetic mechanisms such as DNA methylation are important for the tumorigenesis and maintenance of the altered state of tumor cells. DNA methylation occurs by the addition of a methyl group to carbon 5 of cytosine, catalyzed by the enzyme DNA methyl-transferase, which can change the expression of a gene, including the tumor suppressor genes. In human squamous cell carcinoma, several features have shown the etiological role of genes in tumor development. Among them, FOXE1 gene (forkhead box E1 - thyroid transcription factor) is presented with an important role in susceptibility to disease. Similarly the FOXE1 methylation pattern could alter the expression of this gene in dogs and predisposed to tumor on. Therefore, this study aims to investigate in dogs, the validity of the strategy employed in humans to analyze the FOXE1 methylation status. DNA extraction from fresh frozen tumoral samples was performed by Wizard Genomic® DNA Purification Kit. The methylation status was determined by MSP-PCR (methylation-specific polymerase chain reaction), using 2.0 ng of DNA treated with sodium bisulphate. One hundred micrograms of bisulphite-modified DNA was amplified using primers specific for either methylated or unmethylated DNA (primers sequences are available at http://pathology2.jhu.edu/pancreas/primer.pdf). The analysis of fragments was loaded on to 7% polyacrylamide gels and silver nitrate staining. In this stage of technical approach, 60% were FOXE1 hypermethylated. In conclusion, it was observed that the standard technique for assessing the methylation pattern of gene FOXE1 in humans can be used for the same evaluation in dogs. The correlation of these molecular data with clinical and histopathological parameters may have diagnostic and prognostic value and still be used as a tumor marker for therapeutic decision and surgical approach

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OBJECTIVE: To assess the accuracy of preoperative imaging studies and clinical and endoscopic examinations for recurrent laryngeal carcinoma evaluation. STUDY DESIGN AND SETTING: A retrospective comparative study was performed at a university department on 42 recurrent laryngeal carcinomas. Surgical specimens were cut into whole-organ slices. Histologic findings were compared with the findings of the different preoperative diagnostic modalities. RESULTS: The craniocaudal tumor spread was correctly evaluated by endoscopy and imaging studies in 52% and 24%, respectively, and the contralateral tumor spread in 50% and 52%, respectively. The sensitivity, specificity, and accuracy for detection of tumor infiltration of the thyroid was 48%, 88%, and 64% and of the cricoid 47%, 80%, and 67%. The accuracy of recurrent tumor classification (crT) was 50%; most tumors were underclassified. CONCLUSION: The inadequately evaluated tumor spread and the inadequately classified recurrent tumors were underestimated and underclassified in most cases, respectively.

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Epidermal growth factor (EGF) has widespread growth effects, and in some tissues proliferation is associated with the nuclear localization of EGF and epidermal growth factor receptor (EGFR). In the thyroid, EGF promotes growth but differs from thyrotropin (TSH) in inhibiting rather than stimulating functional parameters. We have therefore studied the occurrence and cellular distribution of EGF and EGFR in normal thyroid, in Graves' disease, where growth is mediated through the thyrotropin receptor (TSHR), and in a variety of human thyroid tumors. In the normal gland the staining was variable, but largely cytoplasmic, for both EGF and EGFR. In Graves' disease there was strong cytoplasmic staining for both EGF and EGFR, with frequent positive nuclei. Nuclear positivity for EGF and particularly for EGFR was also a feature of both follicular adenomas and follicular carcinomas. Interestingly, nuclear staining was almost absent in papillary carcinomas. These findings document for the first time the presence of nuclear EGF and EGFR in thyroid. Their predominant occurrence in tissues with increased growth (Graves' disease, follicular adenoma, and carcinoma) may indicate that nuclear EGF and EGFR play a role in growth regulation in these conditions. The absence of nuclear EGF and EGFR in papillary carcinomas would suggest that the role played by EGF in growth control differs between papillary carcinoma and follicular adenomas/carcinomas of the thyroid.

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Retinoid therapy has been successful for the treatment of skin squamous cell carcinoma (SCC). A suppression of the predominant retinoid X receptor expressed in skin, retinoid X receptor α (RXRα), has been reported in skin SCC. These observations have led to the hypothesis that retinoid receptor loss contributes to the tumorigenic phenotype of epithelial cancers. To test this hypothesis, the RXRα gene was mapped in order to generate a targeting construct. Additionally the transcriptional regulation of the human RXRα a gene in keratinocytes was characterized after identifying the transcription initiation sites, the promoter, and enhancer regions of this gene. The structure is highly conserved between human and mouse. A nontumorigenic human skin-derived cell line called near diploid immortalized keratinocytes (NIKS) has the advantage of growing as organotypic raft cultures, under physiological conditions closely resembling in-vivo squamous stratification. We have exploited the raft culture technique to develop an in-vitro model for skin SCC progression that includes the NIKS cells, HaCaT cells, a premalignant cell line, and SRB 12-p9 cells, a tumorigenic SCC skin cell line. The differentiation, proliferation and nuclear receptor ligand response characteristics of this system were studied and significant and novel results were obtained. RXRs are obligate heterodimerization partners with many of the nuclear hormone receptors, including retinoic acid receptors (RARs), vitamin D3 receptors (VDR), thyroid hormone receptors (T3 R) and peroxisome proliferator activate receptors (PPARs), which are all known to be active in skin. Treatment of the three cell lines in raft culture with the RXR specific ligand BMS649, BMS961 (RARγ-specific), vitamin D3 (VDR ligand), thryoid hormone (T3R ligand) and clofibrate (PPARa ligand), and the combination of BMS649 with each of the 4 receptor partner ligands, resulted in distinct effects on differentiation, proliferation and apoptosis. The effects of activation of RXRs in each of the four-receptor pathways; in the context of skin SCC progression, with an emphasis on the VDR/RXR pathway, are discussed. These studies will lead to a better understanding of RXRα action in human skin and will help determine its role in SCC tumorigenesis, as well as its potential as a target for the prevention, treatment, and control of skin cancer. ^

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Though Hepatocellular Carcinoma is the fifth most common type of cancer, it is the third most deadly and incidence is on the rise. The disease, however, does not affect men and women at similar incidence rates. This thesis was designed to compare the differences in male and female incidence of hepatocellular carcinoma and other common cancer types through age standardized sex ratios for select countries, world-wide. Men were demonstrated an increase in incidence of liver cancer about five to ten years before women in Gharbiah Governorate. Results showed that males had excess incident cases, in decreasing magnitudes, of esophageal, bladder, lung, mouth, liver, stomach, kidney, rectal, lymphoid leukemia, pancreas, non-Hodgkin lymphoma, myeloid leukemia, and colon cancers. There was a slight excess of female gallbladder cancer incidence compared to men, while many more women than men were diagnosed with thyroid cancer. Among different race/ethnicities in the United States, sex ratios resembled US ratios more than those in their countries of origin; this was seen most significantly amongst Hispanic Whites. Sex ratios were generally wider in more developed countries, though more research is needed to determine if this is consistent for all cancer types and countries. Many facets of the disproportionate sex ratios need further exploration, including areas of hormone levels and cultural or lifestyle variances that may lead to differences among men and women and developed and developing countries.^

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INTRODUCTION: The dichotomization of non-small cell carcinoma (NSCLC) subtype into squamous (SQCC) and adenocarcinoma (ADC) has become important in recent years and is increasingly required with regard to management. The aim of this study was to determine the utility of a panel of commercially available antibodies in refining the diagnosis on small biopsies and also to determine whether cytologic material is suitable for somatic EGFR genotyping in a prospectively analyzed series of patients undergoing investigation for suspected lung cancer. METHODS: Thirty-two consecutive cases of NSCLC were first tested using a panel comprising cytokeratin 5/6, P63, thyroid transcription factor-1, 34betaE12, and a D-PAS stain for mucin, to determine their value in refining diagnosis of NSCLC. After this test phase, two further pathologists independently reviewed the cases using a refined panel that excluded 34betaE12 because of its low specificity for SQCC, and refinement of diagnosis and concordance were assessed. Ten cases of ADC, including eight derived from cytologic samples, were sent for EGFR mutation analysis. RESULTS: There was refinement of diagnosis in 65% of cases of NSCLC to either SQCC or ADC in the test phase. This included 10 of 13 cases where cell pellets had been prepared from transbronchial needle aspirates. Validation by two further pathologists with varying expertise in lung pathology confirmed increased refinement and concordance of diagnosis. All samples were adequate for analysis, and they all showed a wild-type EGFR genotype. CONCLUSION: A panel comprising cytokeratin 5/6, P63, thyroid transcription factor-1, and a D-PAS stain for mucin increases diagnostic accuracy and agreement between pathologists when faced with refining a diagnosis of NSCLC to SQCC or ADC. These small samples, even cell pellets derived from transbronchial needle aspirates, seem to be adequate for EGFR mutation analysis.

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Increased incidence of incidental cancer in patients operated for benign thyroid disease has been reported. We report our experience about incidental thyroid cancer (ITC) in order to better characterize this nosologic entity. Between 2001 and 2009 a total of 568 patients underwent surgery for benign thyroid disease. Patients with preoperative cytology undetermined or positive for malignancy were excluded. The most frequent indication for surgery was multinodular or diffuse nontoxic goiter. We performed total thyroidectomy in 499 cases and emithyroidectomy in 69 cases. Final histology revealed ITC in 53 patients (9.3%): 44 had papillary carcinoma (20 classic variant and 24 follicular variant), 4 follicular carcinoma, 4 medullary carcinoma and 1 primitive thyroid paraganglioma. The preoperative diagnosis was multinodular or diffuse goiter in 45 cases of ITC and uninodular goiter in 8 cases. We performed total thyroidectomy in 46 case, emithyroidectomy in 4 patients with past history of lobectomy, emithyroidectomy in 3 patients with following radicalization and central neck dissection. In 14 patients the tumor was multifocal and in 12 of these patients the tumor foci were bilateral. The lesion was a microcarcinoma in 34 cases. Mean diameter of the ITC was 1.14 cm. We retrospectively reconsidered the results of preoperative ultrasound examinations in relation to the exact position of the tumor in the specimens and we found a statistically significant association between echogenicity and papillary histotype. Twenty-six patients were followed up at our Hospital. The mean follow-up period was 38.2 months. A relapse was observed in 3/26 patients. Incidental thyroid cancer in patients operated for benign disease has its own surgical and oncological relevance. A correct preoperative assessment, with a careful selection of nodules for fine-needle aspiration cytology on the basis of ultrasound pattern, could better address the choice of surgical procedure. The non irrelevant incidence of incidental thyroid cancer, the eventuality of multifocality and bilaterality and the possible occurrence of relapse, support that total thyroidectomy without residuum is a valuable option for treating benign thyroid conditions such as multinodular goitre. When an incidental cancer is diagnosed after emithyroidectomy, a radicalization with central neck dissection could be considered. We suggest that natural history of papillary microtumors and the correct surgical approach for these lesions could be better defined with a more extensive use of “Porto proposal” criteria. Incidental thyroid cancer, Papillary microcarcinoma, Papillary microtumors, Total thyroidectomy.

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Understanding the molecular mechanisms of oral carcinogenesis will yield important advances in diagnostics, prognostics, effective treatment, and outcome of oral cancer. Hence, in this study we have investigated the proteomic and peptidomic profiles by combining an orthotopic murine model of oral squamous cell carcinoma (OSCC), mass spectrometry-based proteomics and biological network analysis. Our results indicated the up-regulation of proteins involved in actin cytoskeleton organization and cell-cell junction assembly events and their expression was validated in human OSCC tissues. In addition, the functional relevance of talin-1 in OSCC adhesion, migration and invasion was demonstrated. Taken together, this study identified specific processes deregulated in oral cancer and provided novel refined OSCC-targeting molecules.

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Current guidelines have advised against the performance of (131)I-iodide diagnostic whole body scintigraphy (dxWBS) to minimize the occurrence of stunning, and to guarantee the efficiency of radioiodine therapy (RIT). The aim of the study was to evaluate the impact of stunning on the efficacy of RIT and disease outcome. This retrospective analysis included 208 patients with differentiated thyroid cancer managed according to a same protocol and followed up for 12-159 months (mean 30 ± 69 months). Patients received RIT in doses ranging from 3,700 to 11,100 MBq (100 mCi to 300 mCi). Post-RIT-whole body scintigraphy images were performed 10 days after RIT in all patients. In addition, images were also performed 24-48 hours after therapy in 22 patients. Outcome was classified as no evidence of disease (NED), stable disease (SD) and progressive disease (PD). Thyroid stunning occurred in 40 patients (19.2%), including 26 patients with NED and 14 patients with SD. A multivariate analysis showed no association between disease outcome and the occurrence of stunning (p = 0.3476). The efficacy of RIT and disease outcome do not seem to be related to thyroid stunning.

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Most epidemiological studies concerning differentiated thyroid cancers (DTC) indicate an increasing incidence over the last two decades. This increase might be partially explained by the better access to health services worldwide, but clinicopathological analyses do not fully support this hypothesis, indicating that there are carcinogenetic factors behind this noticeable increasing incidence. Although we have undoubtedly understood the biology and molecular pathways underlying thyroid carcinogenesis in a better way, we have made very little progresses in identifying a risk profile for DTC, and our knowledge of risk factors is very similar to what we knew 30-40 years ago. In addition to ionizing radiation exposure, the most documented and established risk factor for DTC, we also investigated the role of other factors, including eating habits, tobacco smoking, living in a volcanic area, xenobiotics, and viruses, which could be involved in thyroid carcinogenesis, thus, contributing to the increase in DTC incidence rates observed.

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There is an increasing rate of papillary thyroid carcinomas that may never progress to cause symptoms or death. Predicting outcome and determining tumour aggressiveness could help diminish the number of patients submitted to aggressive treatments. We aimed to evaluate whether markers of the immune system response and of tumour-associated inflammation could predict outcome of differentiated thyroid cancer (DTC) patients. Retrospective cohort study. We studied 399 consecutive patients, including 325 papillary and 74 follicular thyroid carcinomas. Immune cell markers were evaluated using immunohistochemistry, including tumour-associated macrophages (CD68) and subsets of tumour-infiltrating lymphocytes (TIL), such as CD3, CD4, CD8, CD16, CD20, CD45RO, GRANZYME B, CD69 and CD25. We also investigated the expression of cyclooxygenase 2 (COX2) in tumour cells and the presence of concurrent lymphocytic infiltration characterizing chronic thyroiditis. Concurrent lymphocytic infiltration characterizing chronic thyroiditis was observed in 29% of the cases. Among all the immunological parameters evaluated, only the enrichment of CD8+ lymphocytes (P = 0·001) and expression of COX2 (P =0·01) were associated with recurrence. A multivariate model analysis identified CD8+ TIL/COX2 as independent risk factor for recurrence. A multivariate analysis using Cox's proportional-hazards model adjusted for the presence of concurrent chronic thyroiditis demonstrated that the presence of concurrent chronic thyroiditis had no effect on prognostic prediction mediated by CD8+ TIL and COX2. In conclusion, we suggest the use of a relatively simple pathology tool to help select cases that may benefit of a more aggressive approach sparing the majority of patients from unnecessary procedures.