References of "Castronovo, Vincenzo"
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See detailThe spectrum of 67-kD laminin receptor expression in breast carcinoma progression.
Viacava, P.; Naccarato, A. G.; Collecchi, P. et al

in Journal of Pathology (The) (1997), 182(1), 36-44

Laminin is a glycoprotein of the basement membrane (BM), involved in a variety of normal and pathological cellular events including tumour invasion and metastasis. Cells bind laminin through different ... [more ▼]

Laminin is a glycoprotein of the basement membrane (BM), involved in a variety of normal and pathological cellular events including tumour invasion and metastasis. Cells bind laminin through different types of receptor. The 67-kD laminin receptor (67LR) is a cell-surface protein which binds laminin with high affinity. 67LR expression has been shown to increase in neoplastic cells, compared with normal tissues, and 67LR seems to play an important role during the first steps of neoplastic progression. In this study, 67LR expression was analysed during the morphological phases of breast cancer progression from normal tissue to invasive carcinoma. A total of 506 formalin-fixed, paraffin-embedded normal breast structures and lesions were stained by immunohistochemistry usign the MLuC5 monoclonal antibody, which is specific for 67LR. The results show that in normal breast and in any kind of breast lesion, myoepithelial and endothelial cells express 67LR. While 67LR is not seen in the epithelium of normal breast, cysts, adenosis, and benign tumours, it is expressed in the epithelial cells of several hyperplasias and carcinomas in situ, both ductal and lobular, as well as in all invasive carcinomas. The 67LR-positive cell subpopulation expands from hyperplastic lesions to invasive carcinoma, suggesting that 67LR could be related to the induction and progression of breast cancer. [less ▲]

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See detailNew insights into the metastasis-associated 67 kD laminin receptor.
Menard, S.; Castronovo, Vincenzo ULg; Tagliabue, E. et al

in Journal of Cellular Biochemistry (1997), 67(2), 155-65

The interactions between tumor cells and laminin or other components of the extracellular matrix have been shown to play an important role in tumor invasion and metastasis. These interactions are mediated ... [more ▼]

The interactions between tumor cells and laminin or other components of the extracellular matrix have been shown to play an important role in tumor invasion and metastasis. These interactions are mediated by different cell surface molecules, including the monomeric 67 kD laminin receptor. This molecule appears to be very peculiar since so, far only a full-length gene encoding a 37 kD precursor protein has been isolated and the mechanism by which the precursor reaches the mature form is not understood. Based on clinical data, which clearly demonstrate the importance of the receptor in tumor progression, studies were conducted to define the structure, expression, and function of this laminin receptor as a step toward developing therapeutic strategies that target this molecule. The data suggest that acylation of the precursor is the key mechanism in maturation of the 67 kD form. The function of the membrane receptor is to stabilize the binding of laminin to cell surface integrins, acting as an integrin-accessory molecule, although homology of the gene encoding the receptor precursor with other genes suggests additional functions. Downregulation of the receptor expression on tumor cells might open new therapeutic approaches to decrease tumor aggressiveness. [less ▲]

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See detailDifferential expression of galectin 3 and galectin 1 in colorectal cancer progression.
Sanjuan, X.; Fernandez, P. L.; Castells, A. et al

in Gastroenterology (1997), 113(6), 1906-15

BACKGROUND & AIMS: Galectins are beta-galactoside-binding proteins possibly involved in tumor progression. The aim of this study was to determine the pattern of galectin 3 and galectin 1 expression and ... [more ▼]

BACKGROUND & AIMS: Galectins are beta-galactoside-binding proteins possibly involved in tumor progression. The aim of this study was to determine the pattern of galectin 3 and galectin 1 expression and involvement in colorectal cancer progression. METHODS: Galectin 3 expression was examined immunohistochemically in 39 samples of normal mucosae, 25 adenomas, 87 carcinomas, and 39 lymph node metastases. Galectin 1 was analyzed in 25 samples of mucosae, 15 adenomas, 25 carcinomas, and 11 metastases. Western blot analysis was also performed. RESULTS: All normal mucosae showed strong nuclear galectin 3 expression, which was down-regulated in the neoplastic progression, because only 60% of adenomas, 48% of carcinomas, and 44% of metastases were strongly positive (P < 0.0001). Cytoplasmic expression was down-regulated in adenomas (16%) but increased again in carcinomas (64%) (P < 0.0001). Galectin 1 expression was mainly detected in stromal cells and correlated with tumor progression from normal mucosae to adenomas and carcinomas (P < 0.0001). CONCLUSIONS: Galectin 3 expression is down-regulated in the initial stages of neoplastic progression, whereas a dissociated cytoplasmic expression increases in later phases of tumor progression. Galectin 1 in colorectal mucosa is predominantly a stromal product whose overexpression is associated with the neoplastic progression of colorectal cancer. [less ▲]

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See detailChanges in the Distribution Pattern of Galectin-1 and Galectin-3 in Human Placenta Correlates with the Differentiation Pathways of Trophoblasts
Maquoi, Erik ULg; van den Brule, F. A.; Castronovo, Vincenzo ULg et al

in Placenta (1997), 18(5-6, Jul-Aug), 433-9

Human placentation is a complex biological phenomenon that results from precisely regulated interactions between cells and the extracellular matrix. Galectin- 1 and galectin-3 belong to a newly defined ... [more ▼]

Human placentation is a complex biological phenomenon that results from precisely regulated interactions between cells and the extracellular matrix. Galectin- 1 and galectin-3 belong to a newly defined family of galactose-binding lectins that can bind several glycoconjugates such as the basement membrane glycoprotein laminin, and are involved in many biological events including cell adhesion. In this study, the expression of these two galectins in first and third trimester normal human placenta was examined using single and double immunohistochemical staining and specific antibodies for galectins and cytokeratins. Galectin-3 was detected in all trophoblastic lineages including villous cytotrophoblasts and extravillous trophoblasts (trophoblastic cell columns, infiltrating trophoblasts, endovascular trophoblasts and placental bed giant cells). On the contrary, galectin-1 distribution was restricted to endometrium. A reduction of galectin-3 expression was observed from the villous trophoblasts to the trophoblastic cell columns. This pattern correlated with the switch from a proliferative to a migratory phenotype. Galectin-1 and galectin-3 were both detected in maternal decidual cells. Our data demonstrate a specific pattern of galectin-1 and galectin-3 expression in trophoblastic tissue, and suggest these lectins could contribute to cell-cell and cell matrix interactions of trophoblast during placentation. [less ▲]

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See detailAntisense galectin-3 alters thymidine incorporation in human MDA-MB435 breast cancer cells
van den Brûle, Frédéric; Bellahcene, Akeila ULg; Jackers, Pascale ULg et al

in International Journal of Oncology (1997), 11(2), 261-264

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See detailLoss of type IV collagen alpha 5 and alpha 6 chains in human invasive prostate carcinomas
Dehan, Pierre ULg; Waltregny, David ULg; Beschin, Alain et al

in American Journal of Pathology (1997), 151(4), 1097-104

Type IV collagen, a major component of basement membranes, is organized in a network responsible for the mechanical resistance of the basement membranes. It also plays a key role in epithelial cell ... [more ▼]

Type IV collagen, a major component of basement membranes, is organized in a network responsible for the mechanical resistance of the basement membranes. It also plays a key role in epithelial cell adhesion to basement membranes. This study was designed to investigate the distribution of type IV collagen alpha-chains in normal, preneoplastic, and malignant prostate basement membranes. For this purpose, immunohistochemistry using specific antibodies raised against the different alpha-chains of type IV collagen was performed in eight normal samples, six prostatic intraepithelial neoplasia, and 20 malignant lesions of the prostate. Our results demonstrate the presence of the "novel" alpha 5 (IV) and alpha 6 (IV) chains along with the "classical" alpha 1 (IV)/alpha 2 (IV) chains in the basement membrane of the normal prostate gland. The alpha 3 (IV) chain was never detected in any prostate specimen. Prostatic intraepithelial neoplasia showed a similar immunostaining pattern to that found in normal glands. In cancer gland basement membranes, we demonstrate for the first time a specific loss of the alpha 5 (IV) and alpha 6 (IV) chains, whereas the classical alpha 1 (IV) and alpha 2 (IV) chains were consistently exhibited. Additionally, type VII collagen colocalized with alpha 5 (IV) collagen chain, and these two proteins, which were always observed in normal and prostatic intraepithelial neoplasia gland basement membranes, were lost in invasive carcinoma basement membranes. This observation raises questions about the possible association or cooperation between alpha 5 (IV)/alpha 6 (IV) chains and anchoring fibrils in prostate glands basement membrane. [less ▲]

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See detailOverexpression of the 67-kD laminin receptor correlates with tumor progression in human prostate cancer
Waltregny, David ULg; de Leval, Laurence ULg; Ménard, Sylvie et al

in Proceedings of the American Association for Cancer Research (1997), 38

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See detailIndependent prognostic value of the 67-kD laminin receptor in human prostate cancer
Waltregny, David ULg; de Leval, Laurence ULg; Ménard, Sylvie et al

in British Journal of Urology (1997), 80(Suppl. 2), 231

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See detailIndependent value of the 67-kilodalton laminin receptor in human prostate cancer
Waltregny, David ULg; de Leval, Laurence ULg; Ménard, Sylvie et al

in Acta Clinica Belgica (1997), 52(2), 93

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See detail67-kD laminin receptor expression correlates with worse prognostic indicators in non-small cell lung carcinomas.
Fontanini, G.; Vignati, S.; Chine, S. et al

in Clinical Cancer Research : An Official Journal of the American Association for Cancer Research (1997), 3(2), 227-31

Tumor samples obtained from 72 patients resected for non-small cell lung cancer were stained immunohistochemically using an immunoperoxidase method and the MLuC5 monoclonal antibody specific for the 67 ... [more ▼]

Tumor samples obtained from 72 patients resected for non-small cell lung cancer were stained immunohistochemically using an immunoperoxidase method and the MLuC5 monoclonal antibody specific for the 67-kDa laminin receptor. Sixty-one of 72 patients (84.7%) displayed a MLuC5-positive reaction, which was usually localized in both the inner surface of the plasmatic membranes and the cytoplasm of neoplastic cells. When we compared the laminin receptor expression with clinicopathological and biological parameters such as histotype, grading, T status, N status, ploidy, proliferative activity, vessel invasion, and p53 protein accumulation, the following results were observed: (a) the mean expression of the receptor was higher in the group of patients with metastatic nodal involvement than in those with uninvolved lymph nodes (P = 0.02); (b) a high Ki-67 score (>13% of positive cells) was observed in tumors with a higher mean value of laminin receptor (P = 0.004); (c) the tumors harboring neoplastic emboli in their vessels showed a higher laminin receptor immunoreactivity (P = 0.02); and (d) a borderline association was found between the high mean value of laminin receptor immunopositivity and p53 accumulation in neoplastic cell nuclei (P = 0.05). Our observations indicate that detection of high tissue levels of 67-kDa laminin receptor is associated with an invasive phenotype in non-small cell lung cancer and may provide further information in the biological characterization of this type of cancer. [less ▲]

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See detailIndependent prognostic value of the 67-kd laminin receptor in human prostate cancer
Waltregny, David ULg; de Leval, Laurence ULg; Menard, Sylvie et al

in Journal of the National Cancer Institute (1997), 89(16), 1224-7

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See detailEnhancement of Tamoxifen-Induced E-Cadherin Function by Ca2+ Channel Antagonists in Human Breast Cancer Mcf7/6 Cells
Charlier, Corinne ULg; Bruyneel, E.; Lechanteur, Chantal ULg et al

in European Journal of Pharmacology (1996), 317(2-3), 413-6

Despite its intensive use in adjuvant breast cancer therapy for more than 30 years, the exact mechanisms of action of tamoxifen have not yet been fully characterized. Tamoxifen was recently shown to ... [more ▼]

Despite its intensive use in adjuvant breast cancer therapy for more than 30 years, the exact mechanisms of action of tamoxifen have not yet been fully characterized. Tamoxifen was recently shown to restore the E-cadherin function of human breast cancer MCF7/6 cells and to suppress their invasive phenotype. Because tamoxifen interacts with targets implicated in Ca2+ homeostasis, we explored the possibility that the restoration of E-cadherin function in MCF7/6 cells induced by this drug could be affected by Ca2+ modulators. Two different Ca2+ channel antagonists (verapamil and nifedipine) potentiated the effect of tamoxifen on E-cadherin function, as evaluated with a fast cell aggregation assay. These molecules decreased the tamoxifen concentration needed to restore the E-cadherin function from 10(-6) M to 10(-7) M. When incubated with a Ca2+ channel agonist, Bay K8644 (methyl-1,4-dihydro-2,6-dimethyl-3-nitro-4-(2-trifluoro-methylphenyl)- pyridine-5-carboxylate), the effect of tamoxifen on E-cadherin function was completely abolished. These results demonstrate that the restoration of the E-cadherin function induced by tamoxifen depends, at least in part, on a Ca2+ pathway, and support the evidence of an effect of tamoxifen on Ca(2+)-dependent mechanisms. Our data also suggest that Ca2+ channel modulators could make it possible to decrease the dose of tamoxifen administered to patients without reducing the therapeutic effects. [less ▲]

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See detailIdentification of the active gene coding for the metastasis-associated 37LRP/p40 multifunctional protein.
Clausse, Nathalie; Jackers, Pascale ULg; Jares, P. et al

in DNA & Cell Biology (1996), 15(12), 1009-23

A 37LRP/p40 polypeptide is of major interest because it is consistently up-regulated in cancer cells in correlation with their invasive and metastatic phenotype. Furthermore, this polypeptide presents ... [more ▼]

A 37LRP/p40 polypeptide is of major interest because it is consistently up-regulated in cancer cells in correlation with their invasive and metastatic phenotype. Furthermore, this polypeptide presents intriguing multifunctional properties because it has been characterized as the precursor of the metastasis-associated 67-kD laminin receptor (67LR) and as a cytoplasmic ribosomal-associated protein. The isolation of the 37LRP/p40 gene is a prerequisite for identifying the molecular mechanisms responsible for the constant up-regulation of the 67LR expression in cancer cells. To date, the active 37LRP/p40 gene has never been identified in any species due to the existence of multiple pseudogenes in most vertebrates genomes. In this study, we report for the first time the gene structure and potential regulatory sequences of the 37 LRP/p40 gene. The chicken genome was selected to undergo this characterization because it is the only known vertebrate that bears a single 37 LRP/p40 gene copy. The 37 LRP/p40 active gene is composed of 7 exons and 6 introns and bears features characteristic of a ribosomal protein gene. It does not bear a classical TATA box and it exhibits several transcription initiation sites as demonstrated by RNase protection assay and primer extension. Analysis of potential regulatory regions suggests that gene expression is driven not only by the 5' genomic region but also by the 5' untranslated and intron 1 sequences. On the basis of gene structure and extensive protein evolutionary study, we found that the carboxyterminal domain of the protein is a conserved lock-and-key structure/function domain that could be involved in the biosynthesis of the higher-molecular-weight 67-kD laminin receptor in vertebrates, whereas the central core of the protein would be responsible for the ribosome associated function. The first identification of the active 37LRP/p40 gene presented in this study is a critical step toward the isolation of the corresponding human gene and the understanding of the molecular mechanisms involved in the up-regulation of its expression during tumor invasion and metastasis. [less ▲]

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See detailTnp-470 (Agm-1470): Mechanisms of Action and Early Clinical Development
Castronovo, Vincenzo ULg; Belotti, D.

in European Journal of Cancer (1996), 32A(14), 2520-7

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See detailExpression of the 67-Kd Laminin Receptor, Galectin-1, and Galectin-3 in Advanced Human Uterine Adenocarcinoma
van den Brule, F. A.; Buicu, C.; Berchuck, A. et al

in Human Pathology (1996), 27(11), 1185-91

Alterations of tumor cell interactions with laminin, a basement membrane glycoprotein, are consistent features of the invasive and metastatic phenotype. Qualitative and quantitative changes in the ... [more ▼]

Alterations of tumor cell interactions with laminin, a basement membrane glycoprotein, are consistent features of the invasive and metastatic phenotype. Qualitative and quantitative changes in the expression of cell surface laminin-binding proteins have been correlated with the ability of cancer cells to cross basement membranes during the metastatic cascade. Such phenotypic modifications are usually associated with poor prognosis. In this study, the authors examined the possibility that expression of three laminin-binding proteins, the 67-kD laminin receptor (67LR), galectin-1, and galectin-3, is altered in human endometrial cancer in a fashion similar to that reported in other carcinomas, such as breast, colon, and ovarian cancer. Twenty advanced uterine adenocarcinomas were analyzed for expression of these three molecules using immunoperoxidase staining and specific antibodies. The authors found a significant increase in the expression of the 67LR and galectin-1 in cancer cells compared with normal adjacent endometrium (P = .0004 and .0022, respectively). As observed in other carcinomas, a significant down-regulation of galectin-3 expression was found in endometrial cancer cells compared with normal mucosa (P = .02). In the galectin-3 positive tumors, galectin-3 was detected in the cytoplasm and/or nucleus of cancer cells. Interestingly, tumors in which galectin-3 was detected only in the cytoplasm were characterized by deeper invasion of the myometrium than lesions where galectin-3 was found both in nucleus and cytoplasm (P = .02). This study shows an alteration of nonintegrin laminin-binding protein expression in advanced human endometrial cancer. Further studies on larger populations should determine the prognostic value of the detection of these laminin-binding proteins in endometrial carcinoma. Inverse modulation of the 67LR and galectin-3 appears to be a phenotypical feature of invasive carcinoma. [less ▲]

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See detailExpression of Bone Sialoprotein in Primary Human Breast Cancer Is Associated with Poor Survival
Bellahcene, Akeila ULg; Menard, S.; Bufalino, R. et al

in International Journal of Cancer = Journal International du Cancer (1996), 69(4), 350-3

We have recently demonstrated that bone sialoprotein (BSP), a bone-matrix protein involved in hydroxyapatite crystal formation, is ectopically expressed in human breast cancers. We explored a possible ... [more ▼]

We have recently demonstrated that bone sialoprotein (BSP), a bone-matrix protein involved in hydroxyapatite crystal formation, is ectopically expressed in human breast cancers. We explored a possible association between expression of BSP in primary breast cancer and patients' survival. We analyzed BSP expression in 454 breast-cancer patients by immunohistochemistry on archival paraffin-embedded material using an anti-BSP polyclonal antibody. BSP expression was correlated to survival, tumor size, axillary lymph-node status and first site of distant metastasis. Of the breast cancers analyzed, 89% expressed detectable amounts of BSP. We found a statistical association between expression of BSP and poor prognosis as indicated by survival curves analyzed using the log rank and the Gehan methods. BSP expression was significantly higher in breast-cancer patients with axillary lymph-node involvement. Interestingly, survival of patients with positive lymph nodes but BSP-negative tumors was significantly higher than that of patients with no lymph-node involvement but BSP-positive cancers. The frequency of bone metastases was higher in the group of patients with BSP-positive tumors (22%) than in the group with BSP-negative cancers (7%). There was a significant increase in the incidence of lung metastases in patients whose tumors were negative for BSP. Our data show that bone sialoprotein expression in breast cancer is associated with poor prognosis. BSP detection also appears to be a valuable marker with which to identify, among the lymph-node-negative patients, those who have high risk of disease progression. [less ▲]

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See detailIsolation from a multigene family of the active human gene of the metastasis-associated multifunctional protein 37LRP/p40 at chromosome 3p21.3.
Jackers, Pascale ULg; Minoletti, Fabiola; Belotti, Dorina et al

in Oncogene (1996), 13(3), 495-503

The 37 kD precursor of the 67 kD laminin receptor (37LRP) is a polypeptide whose expression is consistently upregulated in aggressive carcinoma. Interestingly, the 37LRP appears to be a multifunctional ... [more ▼]

The 37 kD precursor of the 67 kD laminin receptor (37LRP) is a polypeptide whose expression is consistently upregulated in aggressive carcinoma. Interestingly, the 37LRP appears to be a multifunctional protein involved in the translational machinery and has also been identified as p40 ribosome-associated protein. Although highly conserved cDNAs corresponding to this polypeptide have been isolated from several species including vertebrates, invertebrates, plants and prokaryotes, characterization of any of the corresponding active genes has never been reported. In this study, we have cloned an intron-containing fragment which permitted us to isolate the active 37LRP/p40 human gene. This gene contains seven exons and six introns. Ribonuclease protection experiments suggest multiple transcription start sites. The promoter area does not bear a TATA box but contains four Sp1 sites. The first intron is also GC rich containing five Sp1 sites. Intron 4 contains the full sequence of the small nuclear RNA E2 and two Alu sequences are found in intron 3. Fluorescent in situ hybridization localized the 37LRP/p40 active gene on chromosome 3 in the locus 3p21.3 which, interestingly, is a hot spot for genetic alterations in several cancers and particularly in small cell lung carcinoma. [less ▲]

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See detailExpression of the 67 Kd Laminin Receptor in Human Ovarian Carcinomas as Defined by a Monoclonal Antibody, Mluc5
van den Brule, F. A.; Castronovo, Vincenzo ULg; Menard, S. et al

in European Journal of Cancer (1996), 32A(9), 1598-602

Previous immunohistochemical data from our laboratory have demonstrated that expression of the 67 kD laminin receptor (67LR), a cancer-associated, high-affinity laminin-binding protein, is upregulated in ... [more ▼]

Previous immunohistochemical data from our laboratory have demonstrated that expression of the 67 kD laminin receptor (67LR), a cancer-associated, high-affinity laminin-binding protein, is upregulated in ovarian carcinoma cells compared with normal serosal cells, and that this increased expression in cancer cells could be related to patient outcome. The aim of this study was to validate MLuC5, a monoclonal antibody that recognises the 67LR, as a tool to perform future immunohistochemical studies on larger populations of ovarian carcinoma patients. Expression of the 67LR was determined in 51 primary human ovarian carcinoma samples using immunohistochemistry and MLuC5. The 67LR was detected in ovarian carcinoma cell clusters of variable extent. Analysis of the data determined that 67LR expression was significantly increased in the samples from patients with disease progression, compared with those with no evidence of disease after completion of primary therapy, and in pooled grade 2 and 3 tumours compared to borderline and grade 1 tumours (P < 0.05, chi-squared test). No other significant correlation between 67LR expression and other clinicopathological parameters could be established. These data suggest that the 67LR is correlated to ovarian tumour progression. Detection of the 67LR using this monoclonal antibody could constitute an interesting parameter in prognosis determination of ovarian cancer. [less ▲]

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See detailDetection of Bone Sialoprotein in Human Breast Cancer Tissue and Cell Lines at Both Protein and Messenger Ribonucleic Acid Levels
Bellahcene, Akeila ULg; Antoine, Nadine ULg; Clausse, N. et al

in Laboratory Investigation : Journal of Technical Methods & Pathology (1996), 75(2), 203-10

The recent demonstration that bone sialoprotein (BSP) can be detected in human breast cancer tissue by immunoperoxidase suggests that this phosphoprotein is ectopically expressed by malignant mammary ... [more ▼]

The recent demonstration that bone sialoprotein (BSP) can be detected in human breast cancer tissue by immunoperoxidase suggests that this phosphoprotein is ectopically expressed by malignant mammary epithelial cells. Its detection in human breast cancer cells raises questions about its potential role(s) during breast cancer progression. Because BSP is secreted and is present in the serum, the positivity of breast cancer cells for BSP could have been the result of an uptake of the circulating phosphoprotein by the cells rather than of an intrinsic expression. We examined the expression of BSP at both the protein and mRNA levels in nine human breast cancer samples as well as in three human breast cancer cell lines (MCF-7, T47-D, and MDA-MB-231) using immunohistochemistry, flow cytometric analysis, immunoblot, and reverse-transcriptase PCR. BSP was detected at both protein and mRNA levels in human breast cancer tissue and in the three human breast cancer cell lines. Using a specific polyclonal anti-BSP antibody, we showed by both fluorescence-activated cell sorter analysis and immunohistochemistry experiments that all of the human breast cancer cell lines studied express BSP. This was localized at the cell surface and in the cytosol of the estrogen receptor-positive MCF-7 and T47-D cell lines, whereas it was detected only in the cytosol of the estrogen receptor-negative MDA-MB-231 cells. Using the same polyclonal anti-BSP antibody, we were able to identify an approximately 97-kd band on total protein extracts from the three cell lines by immunoblotting. Reverse-transcriptase PCR reactions using specific oligonucleotides performed on total RNA of nine human breast cancer biopsy samples and the three cell lines demonstrated the presence of BSP mRNA in all of the samples examined. This study is the first demonstration that human malignant breast epithelial cell lines express BSP at the protein and mRNA levels. Our study identified MCF-7, T47-D, and MDA-MB-231 cells as useful models for the examination of the molecular mechanisms involved in the ectopic expression of BSP in breast malignant lesions. [less ▲]

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See detailDetection of Hoxa1 Expression in Human Breast Cancer
Chariot, Alain ULg; Castronovo, Vincenzo ULg

in Biochemical and Biophysical Research Communications (1996), 222(2), 292-7

Homeodomain-containing proteins are transcription factors that regulate the coordinated expression of multiple genes involved in development, differentiation and malignant transformation. To better ... [more ▼]

Homeodomain-containing proteins are transcription factors that regulate the coordinated expression of multiple genes involved in development, differentiation and malignant transformation. To better understand the role played by these proteins in breast cancer cells, we demonstrate, using semi-quantitative RT-PCR experiments, that progestin induces HOXA1 mRNAs in MCF7 cells. This is the first evidence of regulation of a HOX gene by steroids. Moreover, we detected HOXA1 expression in a variety of human breast cancer lesions, suggesting that HOXA1 may be required for the establishment of breast cancer cells phenotype. We propose that HOXA1 gene could be one of the orchestrators that regulate breast epithelial cell differentiation and that alteration of HOXA1 expression could play a role in breast cancer progression. [less ▲]

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