Publications by authors named "Magdelenat H"

Unlabelled: This retrospective analysis was designed to confirm the predictive role of urokinase-type plasminogen activator (uPA) and plasminogen activator inhibitor type I (PAI-1) in the outcome of early stage, node-negative breast cancer patients.

Patients And Methods: Node-negative patients having not received adjuvant chemotherapy, and for whom frozen samples were available, were selected.

Results: Among the 169 patients included, 56.

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Hepatic and lung metastases are the leading causes of mortality and major indicators of aggressiveness in colorectal cancer. The underlying molecular mechanisms contributing to the development of metastasis are still unclear. Here, we designed a novel approach to explore gene expression profiles associated with metastasis in human colorectal cancer (hCRC).

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Proteasome-mediated proteolysis is a mechanism for mediating important regulatory proteins within the cell. Proteins that have been targeted for degradation by the proteasome are convalently tagged with a poly-ubiquitin protein chain prior to be recognized by the 19S subunit of proteasome. This degradation system controls the expression of a wide variety of cellular targets including tumor suppressors such as p53, inhibitor of nuclear factor NFkappaB, cyclin-dependent kinase inhibitors such as p21 and p27.

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Mucin O-glycosylation is characterized in cancer by aberrant expression of immature carbohydrate structures (Tn, T, and sialyl-Tn antigens). The UDP-N-acetyl-D-galactosamine: polypeptide N-acetylgalactosaminyltransferases (ppGalNAc-T) family enzymes regulate the initial steps of mucin O-glycosylation and could be responsible for the altered glycosylation observed in cancer. Considering that we recently found the ppGalNAc-T6 mRNA expressed in breast carcinomas, we produced a highly specific monoclonal antibody (MAb T6.

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Completion of the working draft of the human genome has made it possible to analyze the expression of genes according to their position on the chromosomes. Here, we used a transcriptome data analysis approach involving for each gene the calculation of the correlation between its expression profile and those of its neighbors. We used the U133 Affymetrix transcriptome data set for a series of 130 invasive ductal breast carcinomas to construct chromosomal maps of gene expression correlation (transcriptome correlation map).

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Estrogen is the main hormone involved in the development and growth of hormone-dependent breast cancer. Endocrine adjuvant treatment in recent years focused primarily on the use of SERMs, mainly tamoxifen. Tamoxifen actions are complex.

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Disseminated tumor cells (DTC) in bone marrow are independently related to poor outcome in patients with breast cancer. Phenotypic characterization of DTC may be useful to improve evaluation of the metastasizing potential of DTC and also to more accurately target aggressive tumor cells. DTC were screened in bone marrow aspirates from breast cancer patients by immunocytochemistry with an anticytokeratin (anti-CK) antibody (A45B/B3).

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Quantitative reverse transcription-polymerase chain reaction (RT-PCR) used to detect minor changes in specific mRNA concentrations may be associated with poor reproducibility. Stringent quality control is therefore essential at each step of the protocol, including the PCR procedure. We performed inter-laboratory quality control of quantitative PCR between two independent laboratories, using in-house RT-PCR assays on a series of hormone-related target genes in a retrospective consecutive series of 79 breast tumors.

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Aims: To determine whether cell size is related to HER-2/neu status and/or to Akt activation in breast carcinomas. HER-2/neu overexpression is observed in 20-30% of invasive breast carcinomas with poor pronostic features, but little is known about the cell phenotype associated with HER-2/neu activation. Akt has been found to be involved in the HER-2/neu signal transduction pathway and Akt activation has been associated with increased cell size in various models.

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Motivation: Multiclass response (MCR) experiments are those in which there are more than two classes to be compared. In these experiments, though the null hypothesis is simple, there are typically many patterns of gene expression changes across the different classes that led to complex alternatives. In this paper, we propose a new strategy for selecting genes in MCR that is based on a flexible mixture model for the marginal distribution of a modified F-statistic.

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Factors such as warm ischemia and time at room temperature before tissue treatment may influence the results of mRNA expression analyses on tissue specimens obtained during surgery. We evaluated the effect of these factors on RNA integrity and mRNA expression levels by incubating freshly obtained mouse liver tissue at 25 or 37 degrees C for periods of 0-4 h. Changes in the mRNA expression levels of seven genes, Tbp, Eef1a, Fos, Junb, Myc, Vegf, and Glut2, were determined by real-time reverse transcription-polymerase chain reaction.

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The aim of this study was to investigate the relationship between the detection of micrometastatic cells by immunocytochemistry (ICC) with an anticytokeratin antibody and cytokeratin fragment (CYFRA 21-1) expression detected by an immunofluorescent assay in bone marrow of breast cancer patients. Micrometastatic CK+ cells were screened with a pancytokeratin antibody A45 B/B3 from bone marrow aspiration samples of 102 breast cancer patients (65 primary tumors, 10 local recurrences and 27 distant metastases). CYFRA 21-1 levels were assessed in bone marrow supernatant of these patients before collection of the mononucleated interface cells on a Ficoll-Hypaque density gradient and in 20 control patients.

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Mutations in the tumor-suppressor gene p53 have been associated with advanced colorectal cancer (CRC). Irinotecan (CPT-11), a DNA topoisomerase 1 inhibitor, has been recently incorporated to the adjuvant therapy. Since the DNA-damage checkpoint depends on p53 activation, the status of p53 might critically influence the response to CPT-11.

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Purpose: The presence of tumor cells in bone marrow has been reported to represent an important prognostic indicator in breast cancer, but the clinical significance of circulating cells in peripheral blood is less well known. The aim of this study was to evaluate the feasibility of identifying cytokeratin (CK)-expressing cells in peripheral blood with an automat-assisted immunohistochemical detection system and to compare it with detection of tumor cells in bone marrow samples.

Experimental Design: Cytospun Ficoll fractions of peripheral blood and bone marrow were obtained simultaneously in 114 breast cancer patients at different stages of the disease (I to IV) before treatment with chemotherapy.

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The aim of this study was to determine the efficiency of the Hybrid Capture 2 (HC2; Digene, Gaithersburg, MD) human papillomavirus (HPV) assay for the detection of cervical neoplasia. Of the 1,785 patients recruited, 462 (25.88%) were referred for colposcopy owing to previously detected cytologic abnormalities, and 1,323 (74.

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Using a quantitative real-time RT-PCR technique we have compared the expression of a number of genes in two different human breast cancer model systems for development of acquired resistance to antiestrogens. The model system developed at the Danish Cancer Society comprises the cell lines MCF-7, MCF-7/TAMR-1, MCF-7/182R-6 and MCF-7/182R-7, and the model system developed at the Lombardi Cancer Research Center consists of the cell lines MCF-7/LCC1, MCF-7/LCC2 and MCF-7/LCC9. The findings on the well-known parameters estrogen receptor (ER)alpha, progesterone receptor (PR) and epidermal growth factor receptor (EGFR) are in good agreement with previous reports, thus documenting the usefulness of the real-time RT-PCR technique for multiparametric RNA analysis.

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In this report we present an extension of the pooled analysis of the prognostic impact of urokinase-type plasminogen activator (uPA) and its inhibitor PAI-I in breast cancer patients. We analyzed a different endpoint, metastasis-free survival (MFS). We checked the consistency of the estimates for uPA and PAI-1 for relapse-free survival (RFS) and MFS exploring possible sources of heterogeneity.

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There is increasing statistical evidence that the presence of tumour cells in bone marrow detected by immunocytochemistry represents an important prognostic indicator in breast cancer, but their individual capacity to become clinical metastases is unknown. The aim of this study was to assess the proliferative capacity of these occult metastatic cells in the bone marrow of patients with various stages of breast cancer. We obtained bone marrow aspirates from 60 patients with breast cancer before treatment with chemotherapy: 17 stage II, 12 stage III and 31 stage IV.

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B-cell chronic lymphoid leukemia (BCLL) is a highly heterogeneous human malignancy, presumably reflecting specific molecular alterations in gene expression and protein activity that are thought to underlie the variable disease outcome. Most B-CLL cell samples undergo apoptotic death in response to DNA damage. However, a clinically distinct aggressive subset of B-CLL is completely resistant in vitro to irradiation-induced apoptosis.

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Hormone receptor content is the most useful parameter for predicting hormone response therapy in breast cancer. The high frequency of primary and secondary resistance to treatment makes it necessary to find out other parameters in order to improve the prediction of response to treatment. The newly described estrogen receptor beta (ERbeta) is a potential candidate.

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The ubiquitin system regulates diverse biological processes such as DNA replication and repair, biogenesis of ribosome, peroxisome and nucleosome, cell cycle, stress response and signal transduction pathways. Thus, the reported role of the ubiquitin system in apoptotic death control as well the alteration of its control in carcinogenesis should come as no surprise. Indeed, we and other groups have reported that the ubiquitin system is involved in apoptotic cell death of normal human lymphocytes and that this control is altered in B lymphocytes derived from chronic lymphocytic leukemia patients (B-CLL), rendering these malignant cells hypersensitive to specific inhibition of protein degradation/processing through proteasomal function.

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Background: Urokinase-type plasminogen activator (uPA) and its inhibitor (PAI-1) play essential roles in tumor invasion and metastasis. High levels of both uPA and PAI-1 are associated with poor prognosis in breast cancer patients. To confirm the prognostic value of uPA and PAI-1 in primary breast cancer, we reanalyzed individual patient data provided by members of the European Organization for Research and Treatment of Cancer-Receptor and Biomarker Group (EORTC-RBG).

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The current extension of the indications for adjuvant chemotherapy, which predisposes to early menopause, and the media coverage of the benefits of hormone replacement therapy (HRT) have led patients with a history of breast cancer to seek treatments for estrogen deprivation. In breast cancer survivors, most physicians avoid HRT because of concern regarding the potential promotion of growth of occult malignant cells by estrogens, due to the estrogen dependence of breast cancer. Soy phytoestrogens are being promoted as the 'natural alternative' to HRT and have been available without restrictions for several years as nutritional supplements.

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Aims: The hormone receptor (HR) status of breast cancer is an important prognostic factor and predictive parameter of the response to hormone therapy. Enzyme immunoassay (EIA) is currently the standard for determination of HR, but immunohistochemistry (IHC) represents a potentially useful alternative. We used IHC to determine HR status in a large prospective study and compared the results to those obtained by EIA.

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