Gustavo Baretton

Carl Gustav Carus-Institut , Pforzheim, Baden-Wuerttemberg, Germany

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Publications (34)156.55 Total impact

  • Article: Interplay between neural-cadherin and vascular endothelial-cadherin in breast cancer progression.
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    ABSTRACT: INTRODUCTION: Deregulation of cadherin expression, in particular the loss of epithelial (E)-cadherin and gain of neural (N)-cadherin, has been implicated in carcinoma progression. We previously showed that endothelial cell-specific vascular endothelial (VE)-cadherin can be expressed aberrantly on tumor cells both in human breast cancer and in experimental mouse mammary carcinoma. Functional analyses revealed that VE-cadherin promotes tumor cell proliferation and invasion by stimulating transforming growth factor (TGF)-beta signaling. Here, we investigate the functional interplay between N-cadherin and VE-cadherin in breast cancer. METHODS: The expression of N-cadherin and VE-cadherin was evaluated by immunohistochemistry in a tissue microarray with 84 invasive human breast carcinomas. VE-cadherin and N-cadherin expression in mouse mammary carcinoma cells was manipulated by RNA-interference or overexpression, and cells were then analyzed by immunofluorescence, reverse transcriptase-polymerase chain reaction, and western blot. Experimental tumors were generated by transplantation of the modified mouse mammary carcinoma cells into immunocompetent mice. Tumor growth was monitored, and tumor tissue was subjected to histological analysis. RESULTS: VE-cadherin and N-cadherin were largely co-expressed in invasive human breast cancers. Silencing of N-cadherin in mouse mammary carcinoma cells led to decreased VE-cadherin expression and induced changes indicative of mesenchymal-epithelial transition, as indicated by re-induction of E-cadherin, localization of beta-catenin at the cell membrane, decreased expression of vimentin and SIP1, and gain of epithelial morphology. Suppression of N-cadherin expression inhibited also tumor growth in vivo, even when VE-cadherin expression was forced. CONCLUSIONS: Our results highlight the critical role of N-cadherin in breast cancer progression and show that N-cadherin is involved in maintaining the malignant tumor cell phenotype. The presence of N-cadherin prevents the re-expression of E-cadherin and localization of beta-catenin at the plasma membrane of mesenchymal mammary carcinoma cells. N-cadherin is also required to maintain the expression of VE-cadherin in malignant tumor cells but not vice versa. Thus, N-cadherin acts in concert with VE-cadherin to promote tumor growth.
    Breast cancer research: BCR 12/2012; 14(6):R154. · 5.24 Impact Factor
  • Article: Rab31 expression levels modulate tumor-relevant characteristics of breast cancer cells.
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    ABSTRACT: BACKGROUND: Rab proteins constitute a large family of monomeric GTP-binding proteins that regulate intracellular vesicle transport. Several Rab proteins, including rab31, have been shown to affect cancer progression and are related with prognosis in various types of cancer including breast cancer. Recently, the gene encoding rab31 was found to be overexpressed in estrogen receptor-positive breast cancer tissue. In a previous study we found a significant association of high rab31 mRNA expression with poor prognosis in node-negative breast cancer patients. In the present study, we aimed to investigate the impact of rab31 (over)-expression on important aspects of tumor progression in vitro and in vivo. METHODS: Breast cancer cells displaying low (MDA-MB-231) or no (CAMA-1) endogenous rab31 expression were stably transfected with a rab31 expression plasmid. Batch-transfected cells as well as selected cell clones, expressing different levels of rab31 protein, were analyzed with regard to proliferation, cell adhesion, the invasive capacity of tumor cells, and in vivo in a xenograft tumor model. Polyclonal antibodies directed to recombinantly expressed rab31 were generated and protein expression analyzed by immunohistochemistry, Western blot analysis, and a newly developed sensitive ELISA. RESULTS: Elevated rab31 protein levels were associated with enhanced proliferation of breast cancer cells. Interestingly, weak to moderate overexpression of rab31 in cell lines with no detectable endogenous rab31 expression was already sufficient to elicit distinct effects on cell proliferation. By contrast, increased expression of rab31 in breast cancer cells led to reduced adhesion towards several extracellular matrix proteins and decreased invasive capacity through MatrigelTM. Again, the rab31-mediated effects on cell adhesion and invasion were dose-dependent. Finally, in a xenograft mouse model, we observed a significantly impaired metastatic dissemination of rab31 overexpressing MDA-MB-231 breast cancer cells to the lung. CONCLUSIONS: Overexpression of rab31 in breast cancer cells leads to a switch from an invasive to a proliferative phenotype as indicated by an increased cell proliferation, reduced adhesion and invasion in vitro, and a reduced capacity to form lung metastases in vivo.
    Molecular Cancer 08/2012; 11(1):62. · 3.99 Impact Factor
  • Article: Overexpression of the urokinase receptor splice variant uPAR-del4/5 in breast cancer cells affects cell adhesion and invasion in a dose-dependent manner and modulates transcription of tumor-associated genes.
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    ABSTRACT: Abstract mRNA levels of the urokinase receptor splice variant uPAR-del4/5 are associated with prognosis in breast cancer. Its overexpression in cancer cells affects tumor biologically relevant processes. In the present study, individual breast cancer cell clones displaying low versus high uPAR-del4/5 expression were analyzed demonstrating that uPAR-del4/5 leads to reduced cell adhesion and invasion in a dose-dependent manner. Additionally, matrix metalloproteinase-9 (MMP-9) was found to be strongly up-regulated in uPAR-del4/5 overexpressing compared to vector control cells. uPAR-del4/5 may thus play an important role in the regulation of the extracellular proteolytic network and, by this, influence the metastatic potential of breast cancer cells.
    Biological Chemistry 07/2012; · 2.96 Impact Factor
  • Article: Clonal evolution including partial loss of human leukocyte antigen genes favoring extramedullary acute myeloid leukemia relapse after matched related allogeneic hematopoietic stem cell transplantation.
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    ABSTRACT: Relapse of acute myeloid leukemia (AML) after allogeneic hematopoietic stem cell transplantation (HSCT) leaves few therapeutic options, and mechanisms of immune escape of recurring leukemic cells remain poorly understood. Recently, acquired loss of mismatched human leukocyte antigen (HLA) was demonstrated in patients with AML undergoing haploidentical allogeneic HSCT and was suggested not to occur in HLA-matched HSCT. We hypothesized that this mechanism applies to extramedullary AML relapse which occurs frequently after allogeneic HSCT and might also not be restricted to haploidentical HSCT. DNA from extramedullary AML relapse after HSCT was compared with bone marrow at diagnosis with array comparative genomic hybridization to investigate relapse-specific genomic aberrations in relapsing AML after allogeneic HSCT. Formalin-fixed, paraffin-embedded tissues from the same points of time were assessed for HLA, major histocompatibility complex class I chain-related gene A, and TAP2 immunohistochemistry staining to assess cell surface expression of deleted loci encoded on chromosome 6p. Array comparative genomic hybridization revealed a partial loss of chromosome 6p in extramedullary myeloid sarcoma relapse of AML after sustained complete remission was achieved through matched related allogeneic HSCT. Among others, a deleted region 6p21.32-p21.33, which included several HLA class I genes, was detected. These results suggest that the loss of HLA class I haplotype also occurs in AML relapse after HLA-matched related HSCT. Partial loss of several HLA class I genes and subsequent reduced presentation of minor histocompatibility antigens and reduced ligation of activating natural killer-cell receptors may explain the loss of graft-versus-leukemia response and extramedullary AML relapse in tissue with reduced immunologic surveillance.
    Transplantation 02/2012; 93(7):744-9. · 4.00 Impact Factor
  • Article: mRNA expression levels of the biological factors uPAR, uPAR-del4/5, and rab31, displaying prognostic value in breast cancer, are not clinically relevant in advanced ovarian cancer.
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    ABSTRACT: High tumor tissue mRNA expression of the tumor biological factors uPAR, uPAR-del4/5, or rab31 is associated with shorter distant metastasis-free and overall survival in breast cancer patients. To evaluate whether these factors are also clinically relevant in ovarian cancer, we quantified the respective mRNA levels in primary tumor tissue of advanced ovarian cancer patients (n=103) and evaluated their association with clinicopathological parameters and patients' prognosis. mRNA expression levels of all three markers did not show any significant association with overall or progression-free survival, demonstrating that these factors have no prognostic value in advanced ovarian cancer.
    Biological Chemistry 08/2011; 392(11):1047-51. · 2.96 Impact Factor
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    Article: Combined mRNA expression levels of members of the urokinase plasminogen activator (uPA) system correlate with disease-associated survival of soft-tissue sarcoma patients.
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    ABSTRACT: Members of the urokinase-type plasminogen activator (uPA) system are up-regulated in various solid malignant tumors. High antigen levels of uPA, its inhibitor PAI-1 and its receptor uPAR have recently been shown to be associated with poor prognosis in soft-tissue sarcoma (STS) patients. However, the mRNA expression of uPA system components has not yet been comprehensively investigated in STS patients. The mRNA expression level of uPA, PAI-1, uPAR and an uPAR splice variant, uPAR-del4/5, was analyzed in tumor tissue from 78 STS patients by quantitative PCR. Elevated mRNA expression levels of PAI-1 and uPAR-del4/5 were significantly associated with clinical parameters such as histological subtype (P = 0.037 and P < 0.001, respectively) and higher tumor grade (P = 0.017 and P = 0.003, respectively). In addition, high uPAR-del4/5 mRNA values were significantly related to higher tumor stage of STS patients (P = 0.031). On the other hand, mRNA expression of uPA system components was not significantly associated with patients' survival. However, in STS patients with complete tumor resection (R0), high PAI-1 and uPAR-del4/5 mRNA levels were associated with a distinctly increased risk of tumor-related death (RR = 6.55, P = 0.054 and RR = 6.00, P = 0.088, respectively). Strikingly, R0 patients with both high PAI-1 and uPAR-del4/5 mRNA expression levels showed a significant, 19-fold increased risk of tumor-related death (P = 0.044) compared to the low expression group. Our results suggest that PAI-1 and uPAR-del4/5 mRNA levels may add prognostic information in STS patients with R0 status and distinguish a subgroup of R0 patients with low PAI-1 and/or low uPAR-del4/5 values who have a better outcome compared to patients with high marker levels.
    BMC Cancer 06/2011; 11:273. · 3.01 Impact Factor
  • Article: Mutational status of KIT and PDGFRA and expression of PDGFRA are not associated with prognosis after curative resection of primary gastrointestinal stromal tumors (GISTs)
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    ABSTRACT: Background The aim of this study was to investigate if immunohistochemical expression and mutational status of KIT and PDGFRA in GISTs are associated with the clinical course and disease-free survival after curative resection of the primary tumor without adjuvant systemic therapy.Methods Paraffin-embedded tumor sections of 95 GISTs were analyzed for KIT and PDGFRA expression by immunohistochemistry. PDGFRA expression was judged using a scoring system subdividing tumors in negative/weak and strong immunoreactivity groups. For mutation analysis, exons 9, 10, 11, 13, and 17 of KIT and exons 10, 12, 14, and 18 of PDGFRA were sequenced.ResultsOf 95 R0-resected GISTs, 69% showed strong PDGFRA immunoreactivity. Gastric GISTs revealed a significantly higher rate of strong PDGFRA immunoreactivity (P = 0.01) and longer DFS (P = 0.015) than GISTs of the small intestine. KIT mutations were detected in 43 of 63 (68.3%) completely sequenced cases while PDGFRA mutations were identified in 6 cases (10%). In multivariate analysis, neither KIT/PDGFRA expression nor mutational status of KIT or PDGFRA were independent prognostic factors. Only mitotic rate predicted recurrence independently.Conclusion Our data do not support the notion that expression of PDGFRA or mutations in KIT or PDGFRA are independent prognostic factors after curative resection of primary GIST. J. Surg. Oncol. 2011;104:59–65. © 2011 Wiley-Liss, Inc.
    Journal of Surgical Oncology 03/2011; 104(1):59 - 65. · 2.10 Impact Factor
  • Article: Gene expression analysis of HUVEC in response to TF-binding.
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    ABSTRACT: Tissue factor (TF), the cofactor for factor VII/VIIa (FVII/FVIIa) and initiator of the extrinsic pathway, is transiently expressed on intravascular cells under control of cytokines and growth factors. In addition, endothelial cells express a binding site for external TF. In the present study, we investigated gene expression of endothelial cells derived from human umbilical veins (HUVEC) in response to TF-binding to identify differentially expressed genes. HUVEC were treated with recombinant relipidated TF (Innovin) versus nontreated cells, as well as TF/FVIIa versus FVIIa alone. TF binding was measured by ELISA. Gene expression profiles were examined using HG-U133 plus 2.0 arrays (Affymetrix). Gene expression analysis of HUVEC showed 148 up-regulated and 29 down-regulated genes 4h after TF binding. Notably, the genes, which were significantly up- and down-regulated, either by TF alone or by the complex of TF/FVIIa, exhibited a complete overlap, indicating that activation of endothelial cells after binding of external added TF does not depend on FVIIa as has been demonstrated for TF-expressing cells. TF-mediated regulation of gene expression of several genes, involved in regulation of apoptosis, cell adhesion, cell motility, and angiogenesis, was confirmed by qPCR. Furthermore, in case of SELE, TGFB2, TNFAIP3, TNFSF4, TNFSF18, TAGLN, CXCL1, PCF11 antibodies directed to TF clearly inhibited TF-mediated regulation of gene expression. The results demonstrate that interaction of TF with HUVEC via a binding site, independent from FVIIa, may result in regulation of a variety of genes involved in arteriosclerosis, cancer, and cardiovascular diseases.
    Thrombosis Research 03/2011; 127(3):259-63. · 2.44 Impact Factor
  • Article: Mutational status of KIT and PDGFRA and expression of PDGFRA are not associated with prognosis after curative resection of primary gastrointestinal stromal tumors (GISTs).
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    ABSTRACT: The aim of this study was to investigate if immunohistochemical expression and mutational status of KIT and PDGFRA in GISTs are associated with the clinical course and disease-free survival after curative resection of the primary tumor without adjuvant systemic therapy. Paraffin-embedded tumor sections of 95 GISTs were analyzed for KIT and PDGFRA expression by immunohistochemistry. PDGFRA expression was judged using a scoring system subdividing tumors in negative/weak and strong immunoreactivity groups. For mutation analysis, exons 9, 10, 11, 13, and 17 of KIT and exons 10, 12, 14, and 18 of PDGFRA were sequenced. Of 95 R0-resected GISTs, 69% showed strong PDGFRA immunoreactivity. Gastric GISTs revealed a significantly higher rate of strong PDGFRA immunoreactivity (P = 0.01) and longer DFS (P = 0.015) than GISTs of the small intestine. KIT mutations were detected in 43 of 63 (68.3%) completely sequenced cases while PDGFRA mutations were identified in 6 cases (10%). In multivariate analysis, neither KIT/PDGFRA expression nor mutational status of KIT or PDGFRA were independent prognostic factors. Only mitotic rate predicted recurrence independently. Our data do not support the notion that expression of PDGFRA or mutations in KIT or PDGFRA are independent prognostic factors after curative resection of primary GIST.
    Journal of Surgical Oncology 03/2011; 104(1):59-65. · 2.10 Impact Factor
  • Article: Prognostic relevance of tumour cell-associated uPAR expression in invasive ductal breast carcinoma.
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    ABSTRACT: The urokinase-type plasminogen activator receptor (uPAR) is a key molecule for pericellular proteolysis in tumour cell invasion and metastasis. The aim was to evaluate the prognostic impact of uPAR in invasive breast cancer dependent on which cell types within the tumour express uPAR. uPAR expression was analysed by immunohistochemistry in 270 tumour tissue specimens of invasive ductal breast carcinomas using tissue microarrays. For evaluation of uPAR immunoexpression we used the epitope-mapped, uPAR domain II-specific monoclonal antibody IID7. High uPAR score values in both tumour cells (uPAR-Tc) and stromal cells were significantly related to high tumour grade (G3), and inversely correlated with oestrogen receptor status. On multivariate analysis, high uPAR-Tc values contributed independent prognostic information for disease-free survival (hazard ratio 1.93, P = 0.007) when adjusted for prognostically relevant clinicopathological parameters, whereas uPAR expression in stromal cells was not related to prognosis. In addition, elevated uPAR-Tc values were found to be prognostic indicators in clinically relevant subgroups of patients with invasive breast cancer. In invasive breast cancer uPAR expression in invasive carcinoma cells, but not in stromal cells, has a significant impact on patients' prognosis, and contributes to a more aggressive tumour phenotype.
    Histopathology 09/2010; 57(3):461-71. · 3.08 Impact Factor
  • Article: Living with severe dysphagia for 10 years: consequence of misdiagnosis.
    Scandinavian journal of gastroenterology 11/2009; 45(1):122-3. · 2.08 Impact Factor
  • Article: Comparative genomic hybridization-based oncogenetic tree model for genetic classification of breast cancer.
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    ABSTRACT: To describe a genetic progression pathway in breast cancer by a maximum likelihood-based tree model representing the dependencies between chromosomal imbalances. One hundred six cases were studied by comparative genomic hybridization, followed by maximum likelihood estimation of an oncogenetic tree model. The tree model identified 3 clusters with correlated chromosomal imbalances. The first cluster included losses at 4q, 5q, 6q, 9p, 13q and a gain at 17q; the second cluster included gains at 1q, 8q, 16p and 20q; the third cluster included losses at 8p, 11q, 16q and 18q. The imbalances nearest the root of the tree were the loss at 13q (cluster 1), the gain at 1q (cluster 2) and the loss at 18q (cluster 3), reflecting an early change in breast cancer evolution. Cox regression analysis revealed the tumor stage and the grade as relevant for overall survival (p = 0.001) and the tumor stage, the grade and the loss at 16q as relevant for disease-free survival (p = 0.001). Methods like oncogenetic tree analysis provide insights into the genetic progression of breast cancer and may extract relevant markers detected by screening methods like comparative genomic hybridization for further studies.
    Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology 05/2009; 31(2):101-8. · 0.41 Impact Factor
  • Article: Analysis of the pancreatic tumor progression by a quantitative proteomic approach and immunhistochemical validation.
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    ABSTRACT: To increase the knowledge about the development of pancreatic ductal adenocarcinoma, (PDAC) detailed analysis of the tumor progression is required. To identify proteins differentially expressed in the pancreatic intraepithelial neoplasia (PanIN), the precursor lesions of PDAC, we conducted a quantitative proteome study on microdissected PanIN cells. Proteins from 1000 microdissected cells were subjected to a procedure combining fluorescence dye saturation labeling with high resolution two-dimensional gel electrophoresis (2-DE). Differentially regulated protein spots were identified using protein lysates from PDAC tissues as a reference proteome followed by nanoLC-ESI-MS/MS. Thirty-seven single lesions of different PanIN grade (PanIN 1A/B, PanIN 2, PanIN 3) from nine patients were analyzed. Their protein expression was compared with each other, with PDAC cells and with normal ductal cells. The differential expression of differentially regulated protein spots was validated by means of immunohistochemistry using tissue microarrays. Of 2500 protein spots, 86 were found to be significantly regulated (p < 0.05, ratio > 1.6) during PanIN progression. Thirty-one nonredundant proteins were identified by mass spectrometry. Immunohistochemistry revealed that the differential expression of the selected candidate proteins major vault protein (MVP), anterior gradient 2 (AGR 2) and 14-3-3 sigma, annexin A4, and S100A10 could be successfully validated in PanIN lesions. The highly sensitive and robust proteome analysis revealed differentially regulated proteins involved in pancreatic tumor progression. The analysis of normal preneoplastic and neoplastic pancreatic tissue establishes a basis for identification of candidate biomarkers in PanIN progression that can be detected in pancreatic juice and in serum or are candidates for in vivo imaging approaches.
    Journal of Proteome Research 05/2009; 8(4):1647-56. · 5.11 Impact Factor
  • Article: Budesonide is effective in treating lymphocytic colitis: a randomized double-blind placebo-controlled study.
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    ABSTRACT: Budesonide is effective in treating collagenous colitis, but no treatment is established for lymphocytic colitis. We performed a randomized, double-blind, placebo-controlled study to evaluate the effects of budesonide in patients with lymphocytic colitis. Forty-two patients (median age, 61 years) with lymphocytic colitis and chronic diarrhea were randomly assigned to groups that were given oral doses of budesonide (9 mg/d) or placebo for 6 weeks. Nonresponders at week 6 were given open-label budesonide (9 mg/d) for 6 additional weeks. A complete colonoscopy and histologic and quality-of-life analyses were performed at baseline and at week 6. The primary end point was clinical remission at 6 weeks, with last observation carried forward (LOCF). All patients who left the study in clinical remission were followed for relapse. At week 6, 86% of patients given budesonide were in clinical remission (with LOCF) compared with 48% of patients given placebo (P = .010). Furthermore, open-label budesonide therapy induced clinical remission in 7 of 8 patients given placebo. Histologic remission was observed in 73% of patients given budesonide compared with 31% given placebo (P = .030). Only 1 patient discontinued budesonide therapy prematurely. During a mean follow-up period of 14 months, 15 patients (44.1%) experienced a clinical relapse (after a mean of 2 months); 8 of the relapsing patients were retreated with and responded again to budesonide. Budesonide effectively induces clinical remission in patients with lymphocytic colitis and significantly improves histology results after 6 weeks. Clinical relapses occur but can be treated again with budesonide.
    Gastroenterology 04/2009; 136(7):2092-100. · 11.68 Impact Factor
  • Article: Oral budesonide for maintenance treatment of collagenous colitis: a randomized, double-blind, placebo-controlled trial.
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    ABSTRACT: Oral budesonide effectively induces clinical remission in patients with collagenous colitis, a debilitating illness characterized by chronic watery/loose diarrhea, but there is a high rate of relapse after treatment cessation. This randomized, double-blind, placebo-controlled, multicenter study evaluated the efficacy and safety of long-term therapy with oral budesonide (Entocort CIR capsules) for maintenance of clinical remission of collagenous colitis. Patients were aged >18 years with histologically proven collagenous colitis and >3 watery/loose stools per day on >or=4 of the prior 7 days. Open-label oral budesonide 9 mg/d was administered to all patients for 6 weeks. Patients in clinical remission (<or=3 stools per day) at week 6 were subsequently randomized to double-blind oral treatment with budesonide 6 mg/d or matching placebo for 6 months. Relapse was defined as >3 stools per day on >or=4 consecutive days (and included patients withdrawn because of adverse events). Of 48 enrolled patients, 46 (96%) achieved clinical remission at week 6 and were randomized to maintenance budesonide or placebo. There were 21 relapses during maintenance therapy, and almost all occurred during the first 2 months. Budesonide therapy was associated with a significantly lower cumulative rate of relapse compared with placebo (6/23 [26%] and 15/23 [65%], respectively; P = .022), and high correlation between clinical remission and histologic improvement was observed. Budesonide was well tolerated with no serious adverse events. Oral budesonide 6 mg/d is efficacious and well tolerated for long-term maintenance of clinical remission in patients with collagenous colitis.
    Gastroenterology 08/2008; 135(5):1510-6. · 11.68 Impact Factor
  • Article: Vascular endothelial cadherin promotes breast cancer progression via transforming growth factor beta signaling.
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    ABSTRACT: Epithelial-to-mesenchymal transition (EMT) is an important event during carcinoma progression and leads to increased tumor cell malignancy. Here, we show that vascular endothelial (VE)-cadherin is induced during EMT in mammary tumor cells and is aberrantly expressed in invasive human breast carcinomas. VE-cadherin enhanced the capacity of fibroblastoid tumor cells to proliferate, form cord-like invasive structures, and adhere to endothelial cells, characteristics that are key contributors to their increased malignancy and metastatic potential. Consistently, VE-cadherin expression in malignant fibroblastoid tumor cells promoted the growth of experimental mammary carcinomas in vivo. Analysis of the signaling mechanisms involved revealed that VE-cadherin expression influences the levels of Smad2 phosphorylation and expression of target genes of transforming growth factor-beta (TGF-beta), a major mediator of advanced tumor progression and malignant tumor cell proliferation. VE-cadherin might thus promote tumor progression not only by contributing to tumor angiogenesis but also by enhancing tumor cell proliferation via the TGF-beta signaling pathway. This article provides evidence for a novel function of VE-cadherin in tumor progression and reveals a previously unknown molecular link between VE-cadherin expression and TGF-beta signaling. Our findings may have important implications for the clinical application of anti-VE-cadherin strategies.
    Cancer Research 04/2008; 68(5):1388-97. · 7.86 Impact Factor
  • Article: Cup-like acute myeloid leukemia: new disease or artificial phenomenon?
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    ABSTRACT: We investigated cup-like nuclear morphology of acute myeloid leukemia blasts in 266 randomly selected patients and its association with hematologic findings, disease markers and outcome data. Cup-like acute myeloid leukemia was diagnosed in 55 patients (21%). It was associated with female sex, high white blood cell and blast cell counts, normal karyotype, and low CD34 and HLA-DR expression. Mutations of FLT3, NPM1 or both were detected in 84.9% compared with 58.1% in cases without this morphology (p=0.001). There was no influence on response to treatment or survival. Therefore, cup-like nuclear morphology is an indicator of normal karyotype and should guide more specific molecular analyses.
    Haematologica 03/2008; 93(2):283-6. · 6.42 Impact Factor
  • Article: Chromosomal genotype in breast cancer progression: comparison of primary and secondary manifestations.
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    ABSTRACT: The purpose of this study was to compare the chromosomal genotype between breast cancers with and without secondary manifestations and between primary tumors and their secondary manifestations. Eighty six breast cancers, twenty lymph node metastases, ten distant metastases and ten local recurrences were analyzed by comparative genomic hybridization. Tumors with local recurrences showed significant more frequent losses at 2q32 than the tumors without recurrences. Lymph node positive cases showed significant more frequent losses at 9p21 than node negative cases. Lymph node metastases exhibited significant more frequent losses at 7q11, 14q24.3-q31 and 17q22-q24 than their primary tumors. In cases with distant metastases, losses at 5q23 were more frequent than in those without, but not reaching the significance level. The distant metastases showed significant more frequent losses at 5p15, 12q24 and 17q22-q24 than the primary tumors. These results reveal strong evidence that the potential for progression is determined in the primary tumor and that different ways of the development of local recurrences, lymph node and distant metastases exist. After confirmation of the results by interphase FISH on tissue micro arrays, the detection of these specific chromosomal imbalances may contribute to a more individual prediction of prognosis in breast cancer.
    Cellular oncology: the official journal of the International Society for Cellular Oncology 02/2008; 30(1):39-50. · 4.17 Impact Factor
  • Article: Urokinase receptor splice variant uPAR-del4/5-associated gene expression in breast cancer: identification of rab31 as an independent prognostic factor.
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    ABSTRACT: To evaluate the pure prognostic impact of the uPA-receptor splice variant uPAR-del4/5 for lymph node-negative breast cancer patients, and to identify differentially expressed genes associated with high or low uPAR-del4/5 mRNA levels. mRNA transcript levels were measured by real-time PCR in tumor samples from 280 node-negative breast cancer patients who had not received adjuvant systemic therapy. Endpoints were distant metastasis-free survival (DMFS) and overall survival (OS). Gene expression analysis was performed with RNA isolated from breast cancer tissue and breast cancer cell lines using Affymetrix U133a GeneChips. In multivariate analysis, uPAR-del4/5 significantly contributed to the base model of traditional prognostic factors for DMFS (HR = 3.29, P < 0.001) and OS (HR = 2.87, P = 0.002). Using microarrays, seven genes were found to be up-regulated in tumor samples and cancer cell lines with high uPAR-del4/5 mRNA expression. The gene encoding rab31, a member of the Ras oncogene family, was selected for quantitative analysis of mRNA expression in the set of 280 patients. High rab31 values were significantly associated with worse outcome of patients for DMFS (HR = 2.27, P < 0.001) and OS (HR = 2.01, P = 0.008) in multivariate analysis, independent from uPAR-del4/5. The patient subgroup with high uPAR-del4/5 and rab31 levels showed the worst DMFS and OS (P < 0.001, both) compared with tumors with low values of both factors. Our results suggest that uPAR-del4/5 and rab31 mRNA represent independent prognostic markers in breast cancer and may be components of different, but possibly associated, tumor-relevant signaling pathways.
    Breast Cancer Research and Treatment 10/2007; 111(2):229-40. · 4.43 Impact Factor
  • Article: Cytogenetic and molecular genetic analyses of giant cell glioblastoma multiforme reveal distinct profiles in giant cell and non-giant cell subpopulations.
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    ABSTRACT: We have comparatively analyzed mechanisms associated with chromosomal and microsatellite instability in giant cell glioblastoma multiforme (gcGBM) and classic GBM. This included microsatellite instability (MSI), loss of expression of four major mismatch repair (MMR) proteins, aberrations of five chromosomes, EGFR copy number, and TP53 mutations. MSI was more frequent among gcGBM (30 vs. 7.8%, P = 0.054). TP53 mutations were more commonly observed in gcGBM (83.3%), whereas EGFR was amplified in just one gcGBM (8.3%). By tumor cell phenotype-specific cytogenetic analysis of gcGBM, increased chromosome copy numbers were identified in 72-84% of giant cells but in only 4-14% of nongiant cells; in classic GBM, intermediate frequencies were noted (11-49%). Chromosome 10 deletions were found in nongiant cells of all gcGBM cases but in only approximately 45% of the cell population in classic GBM. The present study shows a distinct pattern of cytogenetic alterations in nongiant and giant cell phenotypes in gcGBM and suggests that multinuclear giant cells evolve from nongiant tumor cells at an early tumor stage. Furthermore, the data point to differences in the profile of chromosomal and microsatellite instability in gcGBM and classic GBM that might underscore the distinct pathological features of both tumor subtypes.
    Cancer Genetics and Cytogenetics 06/2007; 175(1):26-34. · 1.39 Impact Factor