References of "Nusgens, Betty"
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See detailIn vitro modulation of human gingival epithelial cell attachment and migration by minocycline-HCL.
Van Heusden, Alain ULg; Nusgens, Betty ULg; Goffinet, Gerhard ULg et al

in Journal of Periodontal Research (1998), 33(6), 377-85

Although the influence of tetracyclines on periodontal connective tissue cells has been the topic of many in vitro and in vivo studies, data regarding their effects on gingival epithelial cells are scarce ... [more ▼]

Although the influence of tetracyclines on periodontal connective tissue cells has been the topic of many in vitro and in vivo studies, data regarding their effects on gingival epithelial cells are scarce. The present in vitro study was designed to examine the influence of minocycline, a semi-synthetic analog of tetracycline, on human gingival keratinocyte (HGK) attachment and migration. Attachment tests were performed with HGK prelabeled by tritiated amino-acids. Increasing concentrations of minocycline (10, 50, 100 micrograms/ml) in the medium produced no significant modification of cell adhesion kinetics compared to control conditions, except for 100 micrograms/ml which statistically significantly (p < 0.05) reduced the number of attached cells beyond 6 h. A 24-h cell preincubation in 10 micrograms/ml of minocycline did not alter the kinetics of HGK attachment. Scanning electron microscopic observations of attached HGK showed that the presence of 10 micrograms/ml of minocycline in the "attachment medium" induced the production of multiple filopodial extensions. Migration tests in Boyden chambers for 40 h demonstrated that HGK preincubation for 24 h in a 10 micrograms/ml minocycline-HCl solution increased significantly (p < 0.005) cell migration towards a gradient of fetal calf serum. The presence of 10 micrograms/ml of minocycline in contact with the keratinocytes in the upper compartment of the migration chambers also produced a significant (p < 0.005) result. In contrast, the presence of minocycline in the lower compartments did not produce any chemoattractive effect. Within the limits of their significance, these results suggest that, at concentrations not beyond 50 micrograms/ml, minocycline could fasten the periodontal wound coverage by epithelial cells and allow the normal reformation of a junctional epithelium. [less ▲]

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See detailAngiogenesis by Fibroblast Growth Factor 4 Is Mediated through an Autocrine Up-regulation of Vascular Endothelial Growth Factor Expression
Deroanne, Christophe ULg; Hajitou, Amin; Calberg-Bacq, Claire-M. et al

in Cancer Research (1997), 57

The infection of normal mouse mammary EF43 cells by a retroviral vector carrying either Fgf-3 (EF43.Fgf-3) or Fgf-4 (EF43.Fgf-4) cDNA resulted in the transformation of cells displaying different ... [more ▼]

The infection of normal mouse mammary EF43 cells by a retroviral vector carrying either Fgf-3 (EF43.Fgf-3) or Fgf-4 (EF43.Fgf-4) cDNA resulted in the transformation of cells displaying different tumorigenic potentials in nude mice (A. Hajitou and C-M. Calberg-Bacq, Int. J. Cancer, 63: 702-709, 1995). EF43.Fgf-4 produced rapidly developing tumors at all sites of inoculation, whereas EF43.Fgf-3 produced slowly growing tumors only in the mammary fat pad. Cells infected with the vector carrying the selection gene alone (EF43.C) were not tumorigenic. The angiogenic properties of these cells were tested in an in vitro angiogenesis model using human umbilical vein endothelial cells (HUVECs) cultured at the surface of a type I collagen gel and their capacity to form tube-like structures on invasion of the gel. Only the conditioned medium (CM) of EF43.Fgf-4 induced an angiogenic morphotype in HUVECs. In parallel, the mRNA expression of matrix metalloproteinase 1 and c-ETS-1 was increased in the HUVECs displaying a differentiated phenotype, whereas the tissue inhibitor of matrix metalloproteinase 1 mRNA level was decreased. Recombinant human fibroblast growth factor 4 (FGF-4) did not induce an angiogenic phenotype in HUVECs by itself. By Western blot analysis, a high expression of vascular endothelial growth factor (VEGF) was detected in the EF43.Fgf-4 CM. This result was confirmed by Northern blot analysis of total RNA extracted from the three cell types; the steady-state level of VEGF mRNA was low and equivalent in EF43.C and EF43.Fgf-3, whereas it was strongly increased in EF43.Fgf-4. Culturing EF43 cells carrying only the selection gene with increasing concentrations of recombinant human FGF-4 resulted in a dose-dependent stimulation of VEGF. The induction of the angiogenic morphotype and the parallel modulations of the biosynthetic phenotype in HUVECs were completely suppressed by adding a neutralizing antibody directed against VEGF to EF43.Fgf-4 CM. Furthermore, inhibition of protein kinase C by bisindoylmaleimide suppressed the angiogenic phenotype induced by the CM of EF43.Fgf-4. Our results point to an indirect angiogenic activity of FGF-4 through the autocrine induction of VEGF secretion by EF43.Fgf-4 cells, an original signaling pathway that might be significant in tumor progression and metastasis. [less ▲]

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See detailcDNA cloning and expression of bovine procollagen I N-proteinase: a new member of the superfamily of zinc-metalloproteinases with binding sites for cells and other matrix components.
Colige, Alain ULg; Li, S. W.; Sieron, A. L. et al

in Proceedings of the National Academy of Sciences of the United States of America (1997), 94(6), 2374-9

Procollagen N-proteinase (EC 3.4.24.14) cleaves the amino-propeptides in the processing of type I and type II procollagens to collagens. Deficiencies of the enzyme cause dermatosparaxis in cattle and ... [more ▼]

Procollagen N-proteinase (EC 3.4.24.14) cleaves the amino-propeptides in the processing of type I and type II procollagens to collagens. Deficiencies of the enzyme cause dermatosparaxis in cattle and sheep, and they cause type VIIC Ehlers-Danlos syndrome in humans, heritable disorders characterized by accumulation of pNcollagen and severe skin fragility. Amino acid sequences for the N-proteinase were used to obtain cDNAs from bovine skin. Three overlapping cDNAs had an ORF coding for a protein of 1205 residues. Mammalian cells stably transfected with a complete cDNA secreted an active recombinant enzyme that specifically cleaved type I procollagen. The protein contained zinc-binding sequences of the clan MB of metallopeptidases that includes procollagen C-proteinase/BMP-1. The protein also contained four repeats that are homologous to domains found in thrombospondins and in properdin and that can participate in complex intermolecular interactions such as activation of latent forms of transforming growth factor beta or the binding to sulfatides. Therefore, the enzyme may play a role in development that is independent of its role in collagen biosynthesis. This hypothesis was supported by the observation that in some tissues the levels of mRNA for the enzyme are disproportionately high relative to the apparent rate of collagen biosynthesis. [less ▲]

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See detailDecrease of Plasma Vitamin E (Alpha-Tocopherol) Levels in Patients with Abdominal Aortic Aneurysm
Sakalihasan, Natzi ULg; Pincemail, Joël ULg; Defraigne, Jean-Olivier ULg et al

in Annals of the New York Academy of Sciences (1996), 800

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See detailLes champs électromagnétiques de faible intensité produisent une vague calcique dans les fibroblastes
Bomans, J.; Lambert, C. A.; Scarpa, B. et al

in Bulletin et Mémoires de l'Académie Royale de Médecine de Belgique (1996), 151(3-4), 243-9250-2

Human fibroblasts display a Ca2+ wave after irradiation with an electromagnetic field (EMF) of low intensity (100 to 900 microT) as seen by LASER confocal microscopy and excitation of Fluo 3. The number ... [more ▼]

Human fibroblasts display a Ca2+ wave after irradiation with an electromagnetic field (EMF) of low intensity (100 to 900 microT) as seen by LASER confocal microscopy and excitation of Fluo 3. The number of excited cells is proportional to the intensity of EMF between 100 and 900 microT. Cellular activation by a dialysable serum factor is required to induce the Ca2+ wave. It also depends on extracellular Ca2+ and active tyrosine kinases and phospholipase C gamma. [less ▲]

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See detailModulation of expression and assembly of vinculin during in vitro fibrillar collagen-induced angiogenesis and its reversal.
Deroanne, Christophe ULg; Colige, Alain ULg; Nusgens, Betty ULg et al

in Experimental Cell Research (1996), 224(2), 215-23

A model of collagen-induced in vitro angiogenesis was used to investigate the modulation of expression and assembly of focal adhesion plaque-associated proteins during the process of differentiation ... [more ▼]

A model of collagen-induced in vitro angiogenesis was used to investigate the modulation of expression and assembly of focal adhesion plaque-associated proteins during the process of differentiation. Human umbilical vein endothelial cells (HUVEC), first attached on an adhesive substratum (gelatin-, fibronectin-, or laminin-coated dish) or adherent collagen gel and then covered by an overlaying collagen get, organized within 3-4 days in tube-like structures (TLS). Removing the overlaying collagen gel from fully differentiated HUVEC induced a reversion of the process and HUVEC returned to a monolayer pattern. Modulations of focal adhesion-associated proteins occurring in HUVEC during the in vitro differentiation process and its reversal were investigated by Western blot analysis. A significant decrease of expression of vinculin, the integrin alpha2 subunit, talin, alpha-actinin, and actin was observed in TLS whereas the amount of FVIII-related antigen did not vary as compared to control monolayer cultures. During reversal, all the reduced proteins were markedly reexpressed. Human skin fibroblasts (HSF), submitted to the same experimental conditions, did not form TLS. Most of the focal adhesion proteins in HSF were similarly modulated by an overlaying collagen gel with the exception of vinculin, which was not modified. This particular protein was therefore more thoroughly investigated. In a nondifferentiated monolayer of HUVEC, a significant proportion of vinculin was organized into a detergent-resistant juxtamembranous structure (focal adhesion plaque) which disassembled early in TLS formation and reassembled during the reversal of the process. The reduction of vinculin during TLS formation was preceded by a downregulation of its mRNA while this mRNA was upregulated during reversal of the morphotype. These results suggest that the modulations of the cytoskeletal and focal adhesion proteins and more specifically of vinculin coupled to its subcellular redistribution are critical and early events in the cascade of mechanochemical signaling during in vitro angiogenesis induced by fibrillar collagen. [less ▲]

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See detailInvestigation of the Relationship between Osteoporosis and the Collagenase Gene by Means of Polymorphism of the 5'upstream Region of This Gene
Thiry-Blaise, L. M.; Taquet, A. N.; Reginster, Jean-Yves ULg et al

in Calcified Tissue International (1995), 56

Osteoporosis is a slowly progressing disease resulting from an imbalance between bone accretion and degradation. As interstitial collagenase is a key enzyme in the degradation of bone matrix, we ... [more ▼]

Osteoporosis is a slowly progressing disease resulting from an imbalance between bone accretion and degradation. As interstitial collagenase is a key enzyme in the degradation of bone matrix, we investigated a possible relationship between the collagenase gene and osteoporosis. Analysis of an amplified genomic DNA fragment from -524 to +52 by denaturing gradient gel electrophoresis and sequencing allowed us to detect three dimorphic sites upstream of base -300, one of them leading to a BanI restriction site. None of the sites could be directly associated with osteoporosis. The allele frequencies of the three dimorphic sites were estimated. The interallelic ratios were high, thus providing new useful genetic markers for linkage analysis. When comparing these ratios in osteoporotic and nonosteoporotic subjects, no significant differences could be observed. [less ▲]

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See detailInvolvement of MMP2 and MMP9 in the development of abdominal aortic aneurysms.
SAKALIHASAN, Natzi ULg; DELVENNE, Philippe ULg; Nusgens, Betty ULg et al

in Cell Biology International (1995), 19(3), 250-51

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See detailExtracellular matrix proteins and basement membrane identification in bovine ovaries and significance for the attachment of cultured preantral follicles
Figueiredo, J. R.; Hulshof, S. C. J.; Thiry, Marc ULg et al

in Theriogenology (1995), 43(5), 845-858

Described in the present paper is the immunolocalization of the extracellular matrix proteins (e.g., fibronectin, collagen Types I and III) in the bovine ovary, with special attention to preantral ... [more ▼]

Described in the present paper is the immunolocalization of the extracellular matrix proteins (e.g., fibronectin, collagen Types I and III) in the bovine ovary, with special attention to preantral follicles. In addition, we have shown, histochemically and ultrastructurally, that mechanically isolated bovine preantral follicles are surrounded by an intact basement membrane. After 24 h of culture in serum-free medium, only 20.4% of these follicles attached to a plastic substrate. We showed that covering the plastic with extracellular matrix proteins (i.e., fibronectin, collagen Type I and matrigel) significantly increased the percentage of attached follicles to 76.0, 65.2 and 80.4%, respectively, while laminin had no effect (18.6%). When preantral follicles were embedded within three-dimensional collagen gels, no loss of follicles was observed. Restoring surface interactions between preantral follicles and the extracellular matrix in vitro, either in a two- or a three-dimensional system, might be important for maintaining follicular viability and growth in the future. [less ▲]

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See detailCharacterization and partial amino acid sequencing of a 107-kDa procollagen I N-proteinase purified by affinity chromatography on immobilized type XIV collagen.
Colige, Alain ULg; Beschin, A.; Samyn, B. et al

in Journal of Biological Chemistry (1995), 270(28), 16724-30

Procollagen I N-proteinase (EC 3.4.24.14), the enzyme that specifically processes type I and type II procollagens to collagen, was isolated from extracts of fetal calf skin. After two chromatographic ... [more ▼]

Procollagen I N-proteinase (EC 3.4.24.14), the enzyme that specifically processes type I and type II procollagens to collagen, was isolated from extracts of fetal calf skin. After two chromatographic steps on concanavalin A-Sepharose and heparin-Sepharose, the semi-purified preparation was used to produce monoclonal antibodies. One reacting antibody was found to recognize not the enzyme itself but type XIV collagen on which the enzyme was bound. This binding, highly sensitive to ionic conditions (plH, salt concentrations) but not affected by non-ionic detergents, was used for affinity chromatography that strongly improved the purification procedure. The enzyme is extensively characterized: 1) it has a molecular mass of 107 kDa as determined by polyacrylamide gel electrophoresis in presence of SDS and of about 130 kDa when estimated by gel filtration on a Sephacryl-S300; 2) in standard assay (pH 7.5, 0.2 M NaCl, 35 degrees C), the activation energy for reaction with amino procollagen type I was 17,000 calories per mole. In the same conditions, Km and Vmax values were, respectively, 435 and 39 nM per hour but varied strongly with pH and salt concentration; 3) the enzyme cleaved the NH2-terminal propeptide of type I procollagen at the specific site, the Pro-Gln bond in the alpha 1 type I procollagen chain; 4) the enzyme contained a high proportion of Gly, Asx, and Glx residues but no Hyp or Hyl; 5) partial amino acid sequences obtained from internal peptides of the enzyme displayed no significant homology with known sequences. The association of procollagen I N-proteinase with a FACIT (fibril-associated collagens with interrupted triple helices) collagen as found here might be of physiological significance. [less ▲]

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See detailThe physiological status of the ovarian donor affects the in-vitro development of isolated bovine preantral follicles
FIGUEIREDO, J. R.; HULSHOF, S. C. J.; VANDENHURK, R. et al

in Theriogenology (1994), 42(8), 1303-1310

Described in the present paper is the effect of the physiological status of the ovarian donor on the development of isolated bovine preantral follicles during 5 d of culture. The preantral follicles were ... [more ▼]

Described in the present paper is the effect of the physiological status of the ovarian donor on the development of isolated bovine preantral follicles during 5 d of culture. The preantral follicles were isolated mechanically from ovaries of calves, or nonpregnant, pregnant and postpartum cows collected at the slaughterhouse. There were no differences observed among calves, nonpregnant and pregnant cows, neither in the percentages of morphologically normal follicles, nor in the mean diameter increase during culture. However, preantral follicles isolated from postpartum animals had a lower viability during culture, as demonstrated by significantly lower percentages of morphologically normal and growing follicles as well as by a levier mean diameter increase. Our findings show that the ovarian source may affect development of bovine preantral follicles in vitro, especially when preantral follicles from postpartum cows were used. [less ▲]

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See detailPreservation of Oocyte and Granulosa Cell Morphology in Bovine Preantral Follicles Cultured in Vitro
Figueiredo, J. R.; Hulshof, S. C.; Van den Hurk, R. et al

in Theriogenology (1994), 41(6), 1333-46

Described in the present paper is a culture system that preserves oocyte and granulosa cell morphology in bovine preantral follicles during 5 d in vitro. The effects of additional hypoxanthine and energy ... [more ▼]

Described in the present paper is a culture system that preserves oocyte and granulosa cell morphology in bovine preantral follicles during 5 d in vitro. The effects of additional hypoxanthine and energy substrata (i.e., pyruvate and glutamine) on the morphology of cultured preantral follicles were investigated. It was shown that addition of a mixture of pyruvate, glutamine and hypoxantine to the culture medium increased the percentage of follicles with an intact oocyte from 29.4 to 78.6%. Morphological criteria are described to discriminate between normal and degenerated preantral follicles during culture by inverted microscopy. In addition, the importance of histological evaluation to judge the quality of oocyte and granulosa cells is demonstrated. [less ▲]

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See detailEnhancement of Tumorigenicity of Human Breast Adenocarcinoma Cells in Nude Mice by Matrigel and Fibroblasts
Noël, Agnès ULg; Gillet, Marie-Claire ULg; Purnell, G. et al

in British Journal of Cancer (1993), 68(5), 909-15

The failure of MCF7 cells to induce the formation of tumours after sub-cutaneous inoculation into athymic nude mice can be obviated by the simultaneous injection of an extract of basement membrane ... [more ▼]

The failure of MCF7 cells to induce the formation of tumours after sub-cutaneous inoculation into athymic nude mice can be obviated by the simultaneous injection of an extract of basement membrane proteins (matrigel). Tumour growth is promoted and the latency period is low (2 to 4 weeks). In the absence of matrigel, the simultaneous inoculation of fibroblasts and MCF7 cells also resulted in the development of tumours, but with a longer latency period (about 2 months). The tumorigenic synergy between matrigel and fibroblasts was evidenced by co-inoculating MCF7 cells MDA-MB 231 cells with fibroblasts and matrigel. This co-inoculation decreased the delay of appearance of the tumours and/or accelerated the tumour growth, depending upon the number of fibroblasts injected. Repeated injections of fibroblasts conditioned medium, at the site of inoculum of tumour cells also enhanced tumour growth, suggesting the involvement of soluble factors secreted by fibroblasts. Histologically, tumours induced by co-inoculation of tumour cells and fibroblasts contained more stromal structures including vimentin-positive cells, fibronectin and interstitial collagens. These data suggest that human tumours may be reconstituted and grown in athymic nude mice using basement membrane components and fibroblasts as inductors. [less ▲]

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See detailInteractions between Tumoral Mcf7 Cells and Fibroblasts on Matrigel and Purified Laminin
Noël, Agnès ULg; Nusgens, Betty ULg; Lapiere, C. H. et al

in Matrix (Stuttgart, Germany) (1993), 13(4), 267-73

A reconstituted basement membrane (matrigel) and/or fibroblasts promote the growth of human breast tumors in athymic nude mice. We have investigated in vitro the effect of matrigel or purified ... [more ▼]

A reconstituted basement membrane (matrigel) and/or fibroblasts promote the growth of human breast tumors in athymic nude mice. We have investigated in vitro the effect of matrigel or purified glycoproteins (laminin and fibronectin) on tumoral MCF7 cells-fibroblasts interactions. In coculture on matrigel, MCF7 cells organized into clusters attached on top of fibroblasts aggregates. During the process resulting in tumor cells-fibroblasts aggregation, fibroblasts actively migrated while MCF7 cells were passively transported. Using purified proteins, specific antibodies and synthetic peptides, we show that cell aggregation induced by immobilized and soluble laminin is antagonized by exogenous fibronectin or fibronectin synthesized by fibroblasts. [less ▲]

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See detailDifferent Mechanisms of Extracellular Matrix Remodeling by Fibroblasts in Response to Human Mammary Neoplastic Cells
Noël, Agnès ULg; Munaut, Carine ULg; Nusgens, Betty ULg et al

in Invasion & Metastasis (1993), 13(2), 72-81

Human breast tumors are often associated with a fibrotic reaction termed desmoplasia. Tumor cells may indirectly modulate the composition of the extracellular matrix by influencing fibroblast properties ... [more ▼]

Human breast tumors are often associated with a fibrotic reaction termed desmoplasia. Tumor cells may indirectly modulate the composition of the extracellular matrix by influencing fibroblast properties. They may also directly interact with collagen fibrils leading to retraction of the matrix. We have studied in vitro the influence of various human mammary tumor cells on the proliferation rate of normal human fibroblasts and on their level of collagen synthesis, as well as their release of collagenase activity. Interactions between neoplastic cells and collagen matrix were investigated by incorporation of tumor cells in collagen gels (lattices) and measurement of their retraction. All cells tested (HBL100, SW613, SA52, MDA-MB-231, MCF7, MCF7/6, MCF7 ras, BT20 and T47D) were able to modulate the composition of the extracellular matrix by one or several of the mechanisms investigated. Our results also demonstrate an opposite regulation of collagen and collagenase production. The effects on the collagen metabolism and on fibroblast proliferation are probably mediated by soluble cytokines since they are reproduced by incubating the fibroblasts in the presence of medium conditioned by tumor cells. The desmoplastic reaction may thus result from different mechanisms dependent upon tumor cell types. [less ▲]

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See detailThe Stimulation of Fibroblasts' Collagen Synthesis by Neoplastic Cells Is Modulated by the Extracellular Matrix
Noël, Agnès ULg; Munaut, Carine ULg; Nusgens, Betty ULg et al

in Matrix (Stuttgart, Germany) (1992), 12(3), 213-20

Human fibroblasts cocultured with neoplastic MCF7 cells produce increased amounts of collagen. A maximal stimulation requires direct cell-cell contacts between tumor cells and fibroblasts. However, this ... [more ▼]

Human fibroblasts cocultured with neoplastic MCF7 cells produce increased amounts of collagen. A maximal stimulation requires direct cell-cell contacts between tumor cells and fibroblasts. However, this effect could be reproduced, although to a lesser extent, by medium conditioned by MCF7 cells, suggesting that it is mediated by a factor produced by MCF7 cells and secreted, at least partly, under a soluble form (Noel et al., 1992). This Collagen Stimulating Factor ("COSF") present in the culture medium displayed a molecular mass between 3,500 to 10,000 daltons, bound to heparin and appeared to be different from the growth factors described until now. The "COSF" can be released from the surface of MCF7 cells by treatment with heparin. The aim of the present work was to investigate the influence of various extracellular matrix components on the production and the release of "COSF". A 3- to 4-fold enhancement of collagen synthesis was observed in coculture on plastic and collagen type I substrates without significant modification of the non-collagen proteins. The increased collagen synthesis was paralleled by an elevation of specific collagen mRNAs level suggesting a regulation at a pretranslational level. On the opposite, in the presence of soluble or insoluble laminin, this stimulation was abolished. Similarly, coculture on "reconstituted basement membrane matrix", matrigel, did not increase collagen production. The "COSF" was found to bind to matrigel and could be released from the basement membrane matrix by treatment with heparin. [less ▲]

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See detailModulation of Collagen and Fibronectin Synthesis in Fibroblasts by Normal and Malignant Cells
Noël, Agnès ULg; Munaut, Carine ULg; Boulvain, A. et al

in Journal of Cellular Biochemistry (1992), 48(2), 150-61

The influence of various normal and malignant human cells on the level of collagen synthesis by human fibroblasts was tested in coculture. As revealed by immunoperoxidase staining, in cocultures with ... [more ▼]

The influence of various normal and malignant human cells on the level of collagen synthesis by human fibroblasts was tested in coculture. As revealed by immunoperoxidase staining, in cocultures with breast adenocarcinoma cells (MCF7, SA52, T47D) fibroblasts synthesized collagen while tumor cells did not. Fibroblasts displayed increased collagen production without change in the overall protein synthesis. Several other types of cells derived from normal human tissues (keratinocytes, normal mammary cells) or from fibrosarcoma, melanoma, cervical carcinoma, choriocarcinoma, or other breast adenocarcinoma (SW613, MDA, BT20) did not affect collagen synthesis of fibroblasts. Although to a lesser extent, this stimulating effect was reproduced by using the conditioned medium (CM) of the active cells but not with CM of the other cell types. A slight stimulation was also obtained when tumoral MCF7 cells and fibroblasts shared the same medium but were physically separated, suggesting that close contact was required for optimal stimulation of collagen synthesis. The collagen synthesis stimulating activity was not related to a modification of fibroblast proliferation rate. The production of collagen types I, III, and VI and fibronectin were increased in cocultures of fibroblasts with MCF7 cells. The increased synthesis of collagen types I and III and fibronectin was paralleled by similar changes in the steady-state level of their mRNAs. On the contrary, the increased production of collagen type VI appeared regulated at a post-transcriptional level. [less ▲]

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See detailEvidence for a relationship between Ehlers-Danlos type VII C in humans and bovine dermatosparaxis.
Nusgens, Betty ULg; Verellen-Dumoulin, C.; Hermanns-Le, Trinh ULg et al

in Nature Genetics (1992), 1(3), 214-7

Ehlers-Danlos (ED) syndrome type VII is characterized by the accumulation of collagen precursors in connective tissues. ED VII A and B are caused by mutations in the genes of alpha 1 and alpha 2 collagen ... [more ▼]

Ehlers-Danlos (ED) syndrome type VII is characterized by the accumulation of collagen precursors in connective tissues. ED VII A and B are caused by mutations in the genes of alpha 1 and alpha 2 collagen I which result in the disruption of the cleavage site of procollagen I N-proteinase. The existence of ED VII C in humans has been hypothesized on the basis of a disorder in cattle and sheep related to the absence of the enzyme. We now present evidence for the existence of this disease in humans, characterized by skin fragility, altered polymers seen as hieroglyphic pictures with electron microscopy, accumulation of p-N-alpha 1 and p-N-alpha 2 collagen type I in the dermis and absence of processing of the p-N-I polypeptides in fibroblast cultures. [less ▲]

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