Transcriptomic changes in human breast cancer progression as determined by serial analysis of gene expression

INTRODUCTION: Genomic and transcriptomic alterations affecting key cellular processes such us cell proliferation, differentiation and genomic stability are considered crucial for the development and progression of cancer. Most invasive breast carcinomas are known to derive from precursor in situ lesions. It is proposed that major global expression abnormalities occur in the transition from normal to premalignant stages and further progression to invasive stages. Serial analysis of gene expression (SAGE) was employed to generate a comprehensive global gene expression profile of the major changes occurring during breast cancer malignant evolution. METHODS: In the present study we combined various normal and tumor SAGE libraries available in the public domain with sets of breast cancer SAGE libraries recently generated and sequenced in our laboratory. A recently developed modified t test was used to detect the genes differentially expressed. RESULTS: We accumulated a total of approximately 1.7 million breast tissue-specific SAGE tags and monitored the behavior of more than 25,157 genes during early breast carcinogenesis. We detected 52 transcripts commonly deregulated across the board when comparing normal tissue with ductal carcinoma in situ, and 149 transcripts when comparing ductal carcinoma in situ with invasive ductal carcinoma (P < 0.01). CONCLUSION: A major novelty of our study was the use of a statistical method that correctly accounts for the intra-SAGE and inter-SAGE library sources of variation. The most useful result of applying this modified t statistics beta binomial test is the identification of genes and gene families commonly deregulated across samples within each specific stage in the transition from normal to preinvasive and invasive stages of breast cancer development. Most of the gene expression abnormalities detected at the in situ stage were related to specific genes in charge of regulating the proper homeostasis between cell death and cell proliferation. The comparison of in situ lesions with fully invasive lesions, a much more heterogeneous group, clearly identified as the most importantly deregulated group of transcripts those encoding for various families of proteins in charge of extracellular matrix remodeling, invasion and cell motility functions

Selective expression of lysyl oxidase (LOX) in the stromal reactions of broncho-pulmonary carcinomas

Lysyl oxidase (LOX) is the extracellular enzyme that initiates the main pathway of collagen and elastin cross-linking. LOX has also been correlated with the ras recision gene, a putative tumour suppressor isolated from revertants of ras-transformed fibroblasts. The present study investigates the potential correlation of LOX-dependent matrix protein cross-linking in the stromal reaction of lung carcinomas, with reference to the architecture of the main stromal reactions accompanying the neoplastic breast tissues. A strong LOX expression was associated with the hypertrophic scar-like stromal reaction found at the front of tumour progression in squamous carcinomas, adenocarcinomas, large cell carcinomas, or at sites of initial extense in bronchiolo-alveolar carcinomas. In contrast, little or no LOX expression was found within the stromal reaction of invasive carcinomas, small cell carcinomas, and neuro-endocrine carcinomas. The significance of LOX expression and of the stromal reaction are discussed, in light of data that associate LOX expression with tumours displaying a rather good prognosis

The Saccharomyces cerevisiae Cdc14 phosphatase is implicated in the structural organization of the nucleolus.

International audienceCdc14, a dual-specificity protein phosphatase, has been previously implicated in triggering exit from mitosis in the yeast Saccharomyces cerevisiae. Using immunofluorescence microscopy and immunogold labeling, we demonstrate that a functional HA-tagged version of the phosphatase Cdc14 localizes to the nucleolus. Moreover, Cdc14-HA co-localized with the nucleolar NOP2 and GAR1 proteins. By immunofluorescence, Cdc14-HA was found in the nucleolus during most of the mitotic cell cycle, except during anaphase-telophase when it redistributed along the mitotic spindle. While this work was in progress, the same pattern of Cdc14 localization was described by others (Visintin et al, Nature 398 (1999) 818). Constitutive overexpression of CDC14 was toxic and led to cell cycle arrest of cells, mainly in G1. This correlated with the appearance of abnormal nuclear structures. A genetic search for suppressors of the lethality associated with CDC14 overexpression identified YJL076W. Because overproduction of Yj1076w buffered the toxic effect of Cdc14 overproduction, this suggested that it might be a substrate of Cdc14. This has indeed been found to be the case by others who recently described Yj1076w/Netl as a nucleolar protein that physically associates with Cdc14 (Shou et al, Cell 97 (1999) 233). The present data confirm several recently uncovered aspects of the regulation of Cdc14 localization and activity and suggest that the level of expression of CDC14 influences the structural organization of the nucleolus

TISSUE IMMUNOTYPING OF TYPE-I AND TYPE-III COLLAGENS

International audiencexx

Characterization of Fat-Storing Cell Lines Derived From Normal and CCl\u3csub\u3e4\u3c/sub\u3e-Cirrhotic Livers. Differences in the Production of Interleukin-6

Liver fat-storing cells (FSC) play an important role in collagen deposition. During the induction of liver cirrhosis, FSC lose their fat droplets, acquire an actin-rich cytoskeleton and transform into myofibroblasts. Myofibroblasts have been associated with increased collagen production in cirrhotic livers. Cultured FSC resemble myofibroblasts. However, it is not known whether regulation of collagen gene expression is similar in FSC obtained from normal or cirrhotic livers. In this communication, we describe the characterization of two fat-storing cell lines, one from normal (NFSC) and one from CCl4-cirrhotic liver (CFSC), obtained after spontaneous immortalization in culture. We studied the effect of serum and various growth factors on cell proliferation. We determined the production of collagen and fibronectin and we analyzed the presence of mRNA transcripts of collagens type I, III, and IV, fibronectin laminin, transforming growth factor-β and interleukin-6. We found that CFSC have a greater serum-dependency than NFSC. NFSC grow with a mixture of insulin and epidermal growth factor, whereas CFSC proliferate only with platelet-derived growth factor. Although we did not find significant differences in the expression of mRNAs for collagen type I, fibronectin and transforming growth factor-β, collagen and fibronectin synthesis was increased 2- and 1.5-fold respectively. NFSC contained 1.6- and 2.0-fold more type III collagen and laminin mRNAs, respectively, than CFSC. Neither cell line expressed type IV collagen mRNA. NFSC but not CFSC produced interleukin-6. These results suggest that, except for the lack of transcripts of collagen type IV, both cell lines resemble primary cultures of FSC. However, significant differences in cell proliferation and interleukin-6 production between the two cell lines were found. We suggest that these cell lines could be useful tools to study possible differences in regulation of matrix production by FSC

<title language="eng">Trypanosoma cruzi antigens detected by immunoelectron microscopy in the spleen of mice serologically positive but parasitologically cured by chemotherapy. (Preliminary Report)

“Documento produzido em parceria ou por autor vinculado à Fiocruz, mas não consta à informação no documento”.Submitted by Ana Maria Fiscina Sampaio ([email protected]) on 2017-05-12T13:24:10Z No. of bitstreams: 1 Andrade SG Trypanosoma cruzi antigens detected....pdf: 382558 bytes, checksum: 230cacd593532d2e55269bfb1a27dcb4 (MD5)Approved for entry into archive by Ana Maria Fiscina Sampaio ([email protected]) on 2017-05-12T13:51:07Z (GMT) No. of bitstreams: 1 Andrade SG Trypanosoma cruzi antigens detected....pdf: 382558 bytes, checksum: 230cacd593532d2e55269bfb1a27dcb4 (MD5)Made available in DSpace on 2017-05-12T13:51:07Z (GMT). No. of bitstreams: 1 Andrade SG Trypanosoma cruzi antigens detected....pdf: 382558 bytes, checksum: 230cacd593532d2e55269bfb1a27dcb4 (MD5) Previous issue date: 1988UNDP/WORLD BANK/WHO Special Program and Conselho N acionai de Desenvolvimento Cientifico e Tecnológico - CNPq.Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilFundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilSem afiliaçãoSem afiliaçãoUniversidade Federal da Bahia. Faculdade de Medicina. Salvador, BA, Brasi

Selective expression of lysyl oxidase (LOX) in the stromal reactions of broncho-pulmonary carcinomas

Lysyl oxidase (LOX) is the extracellular enzyme that initiates the main pathway of collagen and elastin cross-linking. LOX has also been correlated with the ras recision gene, a putative tumour suppressor isolated from revertants of ras-transformed fibroblasts. The present study investigates the potential correlation of LOX-dependent matrix protein cross-linking in the stromal reaction of lung carcinomas, with reference to the architecture of the main stromal reactions accompanying the neoplastic breast tissues. A strong LOX expression was associated with the hypertrophic scar-like stromal reaction found at the front of tumour progression in squamous carcinomas, adenocarcinomas, large cell carcinomas, or at sites of initial extense in bronchiolo-alveolar carcinomas. In contrast, little or no LOX expression was found within the stromal reaction of invasive carcinomas, small cell carcinomas, and neuro-endocrine carcinomas. The significance of LOX expression and of the stromal reaction are discussed, in light of data that associate LOX expression with tumours displaying a rather good prognosis

Collagen immunotyping in human liver: light and electron microscope study.

International audienceTypes I, III, IV, and AB collagens have been extracted from human cirrhotic livers and specific antibodies have been raised in rabbits and purified. Histological immunofluorescent staining of collagen types in normal and fibrotic human livers reveals the respective distribution of the various collagens among the hepatic connective matrix and the modification of the normal pattern in fibrosis: types I and III appear to be the main components of the fibrotic connective matrix in enlarged portal spaces and of the Dissian reticulin framework; type IV collagen deposits are thickened around portal vessels and ducts and outline lobular capillarized sinusoids; type AB collagen appears as thin punctual deposits in portal and Dissian fibrotic connective matrix. Ultrastructural immunoperoxidase labeling of type I and III collagen makes it possible to identify the typical collagen fibers, using 65 nm periodicity, as type I collagen and the fibrillar associated network as type III collagen. Fibers of type I collagen are preferentially organized in large dense bundles in Dense Connective Matrix Organization (DCMO), since fibrillar type III collagen network is predominant in Loose Connective Matrix Organization (LCMO) surrounding vascular and biliary tracts.Types I, III, IV, and AB collagens have been extracted from human cirrhotic livers and specific antibodies have been raised in rabbits and purified. Histological immunofluorescent staining of collagen types in normal and fibrotic human livers reveals the respective distribution of the various collagens among the hepatic connective matrix and the modification of the normal pattern in fibrosis: types I and III appear to be the main components of the fibrotic connective matrix in enlarged portal spaces and of the Dissian reticulin framework; type IV collagen deposits are thickened around portal vessels and ducts and outline lobular capillarized sinusoids; type AB collagen appears as thin punctual deposits in portal and Dissian fibrotic connective matrix. Ultrastructural immunoperoxidase labeling of type I and III collagen makes it possible to identify the typical collagen fibers, using 65 nm periodicity, as type I collagen and the fibrillar associated network as type III collagen. Fibers of type I collagen are preferentially organized in large dense bundles in Dense Connective Matrix Organization (DCMO), since fibrillar type III collagen network is predominant in Loose Connective Matrix Organization (LCMO) surrounding vascular and biliary tracts