9 resultados para Lung Neoplasms -- genetics

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The authors analyzed several cytomorphonuclear parameters related to chromatin distribution and DNA ploidy in typical and atypical carcinoids and in small cell lung cancers. Nuclear measurements and analysis were performed with a SAMBA 200 (TITN, Grenoble, France) cell image processor with software allowing the discrimination of parameters computed on cytospin preparations of Feulgen-stained nuclei extracted from deparaffinized tumor tissues. The authors' results indicate a significant increase in DNA content--assessed by integrated optical density (IOD)--from typical carcinoids to small cell lung carcinomas, with atypical carcinoids showing an intermediate value. Parameters related to hyperchromatism (short and long run length and variance of optical density) also characterize the atypical carcinoids as being intermediate between typical carcinoids and small cell lung cancers. The systematic measurement of these cytomorphonuclear parameters seems to define an objective, reproducible "scale" of differentiation that helps to define the atypical carcinoid and may be of value in establishing cytologic criteria for differential diagnosis.

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BACKGROUND: Breast cancer is a heterogeneous disease. Predictive biological markers (BM) of responsiveness to therapy need to be identified. Evaluation of BM is mainly done at the primary site. However, in the adjuvant therapy of breast cancer, the main goal is control of micrometastases. It is still unknown whether heterogeneity in the expression of BM between the primary site and its micrometastases exists. OBJECTIVE: To evaluate the expression of some BM with potential predictive value from the primary breast cancer site and metastatic ipsilateral axillary lymph nodes. PATIENTS AND METHODS: Focality (percentage of positive cells) and intensity staining scores were evaluated for each marker. Freshly cut sections (4 microm) from embedded blocks of breast cancer fixed in formalin or bouin were put onto superfrost slides (Menzel-Gläser). Protein expression was evaluated immunohistochemically (IHC) using monoclonal antibodies against: topo II-alpha (clone KiS1, 1 microg/ml, Roche) with a trypsine pre-treatment (P); HSP27 (clone G3.1, 1/60, Biogenex), HSP70 (clone BRM.22, 1/80, Biogenex) and HER2 (clone CB11, 1/40, Novocastra; without P); p53 (clone D07, 1/750, Dako) and bcl-2 (clone 124, 1/60, Dako) with citrate buffer as P. RESULTS: Overall, the percentage of discordant marker status in the primary tumour and its metastatic lymph nodes was 2% for HER2, 6% for p53, 15% for bcl-2, 19% for topoisomerase II-alpha, 24% for HSP27 and 30% for HSP70. For the subgroup of patients with positive BM in the primary tumour, the percentage of discordance was 6% for HER2, 7% for p53, 14% for bcl-2, 19% for HSP70, 21% for topoisomerase II-alpha and 36% for HSP27. For the subgroup of patients with positive BM in the lymph nodes, the percentage of discordance was 9% for bcl-2, 15% for HER2 and p53, 21% for topoisomerase II-alpha, 22% for HSP27 and 25% for HSP70. CONCLUSIONS: 1) No biological marker had 100% concordant results. 2) Although some discordant cases might be explained by the limitations of the IHC technique, future studies aiming to evaluate the predictive value of BM in the adjuvant therapy of breast cancer should take into account a possible difference in BM expression between the primary and the metastatic sites.

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BACKGROUND: HER-2/neu status was determined by immunohistochemistry (IHC) and fluorescence in situ hybridisation (FISH) methods in more than 300 paraffin-embedded primary breast cancer samples. MATERIALS AND METHODS: HER-2/neu status was determined by FISH using the PathVysion kit (Vysis) and by IHC using either a monoclonal antibody CB11 or a cocktail of antibodies: the monoclonal TAB250 and the polyclonal pAb1. RESULTS: Of the 324 cases evaluable by IHC, 65 out of 318 (20%) and 24 out of 324 (7%) were scored as positive when using the antibody cocktail and the CB11, respectively. HER-2/neu gene amplification occured in 64 out of 324 cases (20%). Concordance of FISH and IHC was found in 285 out of 318 cases (90%) and 278 out of 324 cases (86%) using the cocktail and the CB11, respectively. CONCLUSION: The cost-effectiveness analysis revealed that the use of a sensitive IHC method followed by confirmation of positive results by FISH considerably decreased the FISH costs and may become standard practice for HER-2/neu evaluation.

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Fifty-one in vivo characterized autonomous single adenomas have been studied for functional parameters in vitro, for gene and protein expression and for pathology, and have been systematically compared to the corresponding extratumoral quiescent tissue. The adenomas were characterized by a high level of iodide trapping that corresponds to a high level of Na+ /iodide symporter gene expression, a high thyroperoxidase mRNA and protein content, and a low H2O2 generation. This explains the iodide metabolism characteristics demonstrated before, ie, the main cause of the "hot" character of the adenomas is their increased iodide transport. The adenomas spontaneously secreted higher amounts of thyroid hormone than the quiescent tissue and in agreement with previous in vivo data, this secretion could be further enhanced by thyrotropin (TSH). Inositol uptake was also increased but there was no spontaneous increase of the generation of inositol phosphates and this metabolism could be further activated by TSH. These positive responses to TSH are in agreement with the properties of TSH-stimulated thyroid cells in vitro and in vivo. They are compatible with the characteristics of mutated TSH receptors whose constitutive activation accounts for the majority of autonomous thyroid adenomas in Europe. The number of cycling cells, as evaluated by MIB-1 immunolabeling was low but increased in comparison with the corresponding quiescent tissue or normal tissue. The cycling cells are observed mainly at the periphery; there was very little apoptosis. Both findings account for the slow growth of these established adenomas. On the other hand, by thyroperoxidase immunohistochemistry, the whole lesion appeared hyperfunctional, which demonstrates a dissociation of mitogenic and functional stimulations. Thyroglobulin, TSH receptor, and E-cadherin mRNA accumulations were not modified in a consistent way, which confirms the near-constitutive expression of the corresponding genes in normal differentiated tissue. On the contrary, early immediate genes expressions (c-myc, NGF1B, egr 1, genes of the fos and jun families) were decreased. This may be explained by the proliferative heterogeneity of the lesion and the previously described short, biphasic expression of these genes when induced by mitogenic agents. All the characteristics of the autonomous adenomas can therefore be explained by the effect of the known activating mutations of genes coding for proteins of the TSH cyclic adenosine monophosphate (cAMP) cascade, all cells being functionally activated while only those at the periphery multiply. The reason of this heterogeneity is unknown.

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Induction of cell proliferation by mitogen or growth factor stimulation leads to the specific induction or repression of a large number of genes. To identify genes differentially regulated by the cAMP-dependent transduction pathway, which is poorly characterized so far, we used the cDNA expression array technology. Hybridizations of Atlas human cDNA expression arrays with (32)P-labeled cDNA probes derived from control or thyrotropin (TSH)-stimulated dog thyrocytes in primary culture generated expression profiles of hundreds of genes simultaneously. Among the genes that displayed modified expression, we selected the transcription factor ID3, whose expression was increased by a cAMP-dependent stimulus. ID3 overexpression after TSH stimulation was first verified by Northern blotting analysis, and its mRNA regulation was then investigated in response to a variety of agents acting on thyrocyte proliferation and/or differentiation. We show that: (1) ID3 mRNA induction was stronger after stimulation of the cAMP cascade, but was not restricted to this signaling pathway, as phorbol myristate ester (TPA) and insulin also stimulated mRNA accumulation; (2) in contrast, powerful mitogens for thyroid cells, epidermal growth factor and hepatocyte growth factor, did not significantly modify ID3 mRNA levels; (3) ID3 protein levels closely parallelled mRNA levels, as revealed by immunofluorescence experiments showing a nuclear signal regulated by TSH; (4) in papillary thyroid carcinomas, ID3 mRNA was downregulated. Our results suggest that ID3 expression might be more related to the differentiating process induced by TSH than to the proliferative action of this hormone.

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We report on a heart-lung transplant recipient who presented with pulmonary tuberculosis (TB) 2.5 months after transplantation and then developed a paradoxical reaction after 4 months of adequate anti-TB treatment. She eventually recovered with anti-TB and high-dose steroid treatments. METHODS: Using sequential bronchoalveolar lavages, we assessed the inflammatory response in the lung and investigated the alveolar immune response against a Mycobacterium tuberculosis antigen. RESULTS: The paradoxical reaction was characterized by a massive infiltration of the alveolar space by M. tuberculosis antigen-specific CD4(+) T cells and by the presence of a CD4(-)CD8(-) T lymphocyte subpopulation bearing phenotypic markers (CD16(+)/56(+)) classically associated with NK cells. CONCLUSION: This case report illustrates that even solid organ transplant recipients receiving intense triple-drug immune suppression may be able to develop a paradoxical reaction during TB treatment. Transplant physicians should be aware of this phenomenon in order to differentiate it from treatment failure.

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Overexpression and amplification of the HER-2 oncogene in patients with breast cancer has correlated with early onset of metastasis, resistance to hormonal therapy and some forms of chemotherapy, and shortened survival. Therefore, evaluation of this putative prognostic or predictive factor seems critical. Because different antibodies are used for the detection of the 185-kd HER-2 oncoprotein, we studied the sensitivity of 3 frequently used antibodies. Immunohistochemistry results were correlated with gene amplification level as assessed by fluorescence in situ hybridization. Protein overexpression was found in 17.2% and 12.5% of cases using antibodies against the external (TAB250) and internal (CB11) domains of the protein, respectively, and in 38.0% of cases using a rabbit polyclonal antibody. Fluorescence in situ hybridization was successful in all 160 tumors, and amplification was found in 37 tumors (23.1%). The monoclonal antibody TAB250 had the lowest misclassification rate, 9.6% (sensitivity, 67%; specificity, 97.5%).

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This study has investigated the effects of herpes simplex thymidine kinase gene (HSV-tk) transfer followed by ganciclovir treatment as adjuvant gene therapy to surgical resection in patients with recurrent glioblastoma multiforme (GBM). The study was open and single-arm, and aimed at assessing the feasibility and safety of the technique and indications of antitumor activity. In 48 patients a suspension of retroviral vector-producing cells (VPCs) was administered by intracerebral injection immediately after tumor resection. Intravenous ganciclovir was infused daily 14 to 27 days after surgery. Patients were monitored for adverse events and for life by regular biosafety assaying. Tumor changes were monitored by magnetic resonance imaging (MRI). Reflux during injection was a frequent occurrence but serious adverse events during the treatment period (days 1-27) were few and of a nature not unexpected in this population. One patient experienced transient neurological disorders associated with postganciclovir MRI enhancement. There was no evidence of replication-competent retrovirus in peripheral blood leukocytes or in tissue samples of reresection or autopsy. Vector DNA was shown in the leukocytes of some patients but not in autopsy gonadal samples. The median survival time was 8.6 months, and the 12-month survival rate was 13 of 48 (27%). On MRI studies, tumor recurrence was absent in seven patients for at least 6 months and for at least 12 months in two patients, one of whom remains recurrence free at more than 24 months. Treatment-characteristic images of injection tracks and intracavity hemoglobin were apparent. In conclusion, the gene therapy is feasible and appears to be satisfactorily safe as an adjuvant to the surgical resection of recurrent GBM, but any benefit appears to be marginal. Investigation of the precise effectiveness of this gene therapy requires prospective, controlled studies.

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SWAP-70-like adapter of T cells (SLAT) is a novel guanine nucleotide exchange factor for Rho GTPases that is upregulated in Th2 cells, but whose physiological function is unclear. We show that SLAT-/- mice displayed a developmental defect at one of the earliest stages of thymocyte differentiation, the double-negative 1 (DN1) stage, leading to decreased peripheral T cell numbers. SLAT-/- peripheral CD4+ T cells demonstrated impaired TCR/CD28-induced proliferation and IL-2 production, which was rescued by the addition of exogenous IL-2. Importantly, SLAT-/- mice were grossly impaired in their ability to mount not only Th2, but also Th1-mediated lung inflammatory responses, as evidenced by reduced airway neutrophilia and eosinophilia, respectively. Levels of Th1 and Th2 cytokine in the lungs were also markedly reduced, paralleling the reduction in pulmonary inflammation. This defect in mounting Th1/Th2 responses, which was also evident in vitro, was traced to a severe reduction in Ca2+ mobilization from ER stores, which consequently led to defective TCR/CD28-induced translocation of nuclear factor of activated T cells 1/2 (NFATc1/2). Thus, SLAT is required for thymic DN1 cell expansion, T cell activation, and Th1 and Th2 inflammatory responses.