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P Birembaut

Publications and source records attributed to P Birembaut.

At least 55 records · Page 3Linked to original sources
PubMed1999

[Oncogenic mucosal human papillomaviruses in Bowen's disease of the hands].

INTRODUCTION: The association between genital Bowen Disease (BD) and human papillomavirus (HPV) especially HPV-16 infection is well known, but it is more rarely related to extragenital BD. The aim of this study was to detect the presence of oncogenic HPV infection in the BD of the hands considering the histology and the presence of oncogenic HPV detected by in situ hybridization (ISH) and polymerase chain reaction (PCR). MATERIAL AND METHODS: Eleven formalin-fixed and paraffin-embedded samples of BD of the hands were selected. We looked for koilocytosis using standard histological procedure. ISH was performed using genomic HPV DNA probes types 16, 18 and 33 labeled with digoxigenin. Next, with a new amplification system using biotinyled tyramide (Kit Dako Gen Point K620) was used to detect hybrids. Otherwise, Baay's HPV type specific primers (type 16, 18, 31 et 33) were chosen for PCR. RESULTS: Koilocytosis were observed in all cutaneous samples. HPV 16 was detected in 9/11 cases (82 p. 100): 2/10 with ISH and 9/11 with PCR. DISCUSSION: We report here the largest series of BD of the hands, associated with HPV type 16 infection. This high rate (82 p. 100) compared to the other series is linked to the high sensitivity of PCR and is increased by the choice of Baay's oligonucleotide primers. Besides, the low HPV rate (2/10) by ISH, is similar to those obtained in the other series. Although ISH is less sensitive than PCR, the morphological study was useful to argue the pathogenicity of HPV. Finally, the high prevalence of genital oncogenic HPV on the hands, plaid in the scratching hypothesis resulting in autoinoculation from HPV lesions in the genital region.

Aged↗
PubMed1999

Increased serum stromelysin-1 levels in systemic lupus erythematosus: lack of correlation with disease activity.

OBJECTIVE: In view of evidence that stromelysin-1 and collagenase-1 are involved in tissue injury in inflammatory joint diseases, we sought to determine whether matrix metalloproteinases (MMP) are implicated in the pathophysiology of systemic lupus erythematosus (SLE). METHODS: Seventy-three patients with SLE and 39 healthy subjects were evaluated. Serum levels of MMP and tissue inhibitor of metalloproteinases were measured. RESULTS: Serum stromelysin-1 levels were significantly increased in patients with SLE (416+/-252 ng/ml) compared to healthy subjects (125+/-93 ng/ml). No correlation between serial measurements of stromelysin-1 and disease activity in SLE patients was noted. Serum collagenase-1, gelatinase A, and TIMP-1 levels were not increased in SLE. CONCLUSION: Serum concentrations of stromelysin-1 are increased in SLE, but the levels do not correlate with disease activity.

Disease Progression↗
PubMed1998

Comparative analysis of human papillomavirus detection by hybrid capture assay and routine cytologic screening to detect high-grade cervical lesions.

A commercial HPV detection test, Hybrid Capture (HC), designed to detect 14 HPV types divided into high-risk and low-risk groups, has been evaluated. A total of 1064 scrapes from 1028 unselected women attending routine cytologic screening were tested and results were compared with those of classic cytologic screening and cervical biopsies. The reliability of the test was also evaluated on 38 fresh conization samples. HPV DNA was detected in 108 women (10.5%), including 90 infected by a high-risk HPV (8.8%); 25 high-grade lesions were detected histologically, and high-risk HPV was found in 16 of these 25 women (64%), and in 27 (71%) of the 38 conization samples. The overall sensitivity of HC in detecting high-grade SIL on cervical scrapes and conization samples was 71.2%, while its positive predictive value was 17.8%. Classic cytologic screening appeared to be the most sensitive method (84%) for detecting high-grade SIL, with a positive predictive value of 91.3%. The lower sensitivity of HC limits its use for screening high-grade lesions on a large scale, even though it may be useful for reducing cytologically false-negative results. Moreover, the quantitative approach provided by the HC assay for assessment of the viral load cannot clearly distinguish among cases with or without high-grade lesions.

Adolescent↗
PubMed1998

A comparative study of cryogenic lesions in organ-cultured human skin and in reconstituted human skin equivalent.

Cryosurgery is a technique that is widely used in the treatment of cutaneous tumors. However, there are still features of healing in cryosurgery wounds that are incompletely understood and necessitate further study. In the present paper, we describe two in vitro models that were developed to study the initial stages of development of the cryolesion: reconstituted human skin and organ-cultured human skin. Cryolesions were generated in both models by applying a 2-mm-diameter cryoprobe at -196 degrees C for 35 s. Histological features were analyzed at days 0, 3, 5, and 14 following cryotreatment and showed epidermal detachment and keratinocyte necrosis very close to the findings reported in vivo. Results were similar in the two models. Gross alteration of the dermal architecture was noticed beneath the cryolesion, particularly in the reconstituted skin model. Cell proliferation was investigated at days 0, 3, and 5 by [3H]thymidine incorporation and Ki-67 antigen immunolabeling. In the case of organ-cultured skin, a significant increase in keratinocyte and fibroblast proliferation was observed at day 3, compared to the controls. At day 5, a return to the basic level was noticed. This was not observed in the reconstituted skin model at either day 3 or day 5. These data led us to propose that organ-cultured skin may be a useful model for evaluating the response of human skin to freezing; reconstituted skin was not adequate for this purpose.

Cryosurgery↗
PubMed1998

Decreased number of nucleolar organizing regions in collagen lattice cultured fibroblasts.

Dermal fibroblasts cultivated in tridimensional matrices (lattices) of collagen exhibit a very low metabolic activity, and a low protein synthesis in particular. We have previously shown that ribosomal RNA content and half-life were decreased in collagen lattice cultured fibroblasts when compared to monolayer cultured fibroblasts. In this study, we seeded fibroblasts in collagen lattices and investigated the influence of matrix on the number of nucleolar organizing regions. We found that fibroblasts in fully retracted lattices exhibited a significant decrease of 45% (P < 0.001) in the number of nucleolar organizing regions when compared to monolayer cultured fibroblasts. This decrease was correlated to the decrease in ribosomal RNA content. These data suggest that extracellular matrix induces early alterations of synthesis and/or processing of ribosomal RNAs, explaining, at least partly, the resulting low metabolic activity.

Adult↗
PubMed1998

Membrane-type metalloproteinases in tumor invasion.

Matrix metalloproteinases (MMPs) are members of a multigene family of zinc-dependent enzymes involved in the degradation of numerous extracellular matrix (ECM) components. Among these enzymes, membrane-type MMPs (MT-MMPs) play a major role in the activation of progelatinase A (MMP-2). The molecular structure of these enzymes is characterized by a transmembrane domain and the presence of an insertion of 11 amino-acids between the pro-peptide and the catalytic domains, which may be cleaved by furin-like enzymes leading to the activated form of the enzymes. MT1-MMP appears to play a dual role in extracellular matrix remodeling through activation of progelatinase A and procollagenase 3 and direct cleavage of some ECM macromolecules such as gelatin, type I collagen and fibronectin. Tissue inhibitor of MMPs-2 (TIMP-2) serves as an intermediate in progelatinase A activation by binding to MT1-MMP and progelatinase A on the plasma membrane. In vivo, MT1-MMP is overexpressed in malignant tumor tissues in which it was mainly localized in stromal cells surrounding the neoplastic tissue. These peritumoral fibroblasts, under particular stimuli, would be induced to overexpress MT1-MMP and consequently activate gelatinase A leading to ECM degradation. The expression of MT1-MMP is however observed in vitro in the invasive tumor cells which might represent an late stage of tumor progression. All these data confirm the important role of MT-MMPs in tumor invasion and highlight a cooperation between tumor and stromal cells for the production of these enzymes. The contribution of MMPs in a metastatic process leads to the development of novel therapies using inhibitors of these enzymes. Among a multitude of synthetic inhibitors generated, Marimastat is already clinically employed in cancer treatment.

Animals↗
PubMed1998

Association of fibroblastoid features with the invasive phenotype in human bronchial cancer cell lines.

The acquisition of a metastatic phenotype by epithelial cells implicates a series of changes altering their differentiation, their overall behavior and morphology. In the present study, we have examined the relationships between the cellular morphology, E-cadherin expression, matrix metalloproteinases expression and in vitro invasive properties in two human bronchial immortalized cell lines. The (16HBE14o-) cell line which did not show any invasive abilities in the Boyden chamber assay displayed a typical epithelial morphology in monolayer, expressed high levels of E-cadherin and synthesized neither MMP-2 and MT1-MMP nor vimentin. In contrast, the BZR cell line which was highly invasive displayed a more elongated phenotype in monolayer, did not produce E-cadherin but expressed vimentin, MMP-2 and MT1-MMP. Our data therefore suggest that the metastatic progression of broncho-pulmonary cancer cells results in a cellular dedifferentiation and the gain of some mesenchymal attributes (loss of E-cadherin and expression of vimentin) associated with enhanced degradative properties (expression of metalloproteinases).

Bronchial Neoplasms↗
PubMed1998

DNA-EIA to detect high and low risk HPV genotypes in cervical lesions with E6/E7 primer mediated multiplex PCR.

BACKGROUND: Oncogenicity of human papillomavirus (HPV) DNA in premalignant and malignant uterine cervical diseases is mainly induced by E6/E7 open reading frame (ORF). The presence of an oncogenic HPV DNA may be a diagnostic marker for the detection of cytologically negative smears. AIMS: To evaluate an original polymerase chain reaction enzyme immunoassay (PCR-EIA) for the detection and typing of oncogenic and non-oncogenic HPV types. METHODS: The test was an original multiplex labelled PCR-EIA for the detection and typing of oncogenic and non-oncogenic HPV using three consensus sequence primers within the oncogenic E6/E7 ORF. One primer was dinitrophenyl (DNP) labelled and the DNP labelled amplimers could be further hybridised with specific biotinylated oligoprobes mixed in only two cocktails: oncogenic (16, 18, 31, 33, 35, 52, and 58) and non-oncogenic (6 and 11) HPV types in only two wells; then biotinylated oligoprobes were deposited in streptavidin-coated microplates. The PCR-EIA was validated on HPV plasmids (types 6, 11, 16, 18, 31, 35, 52, and 58) and used to evaluate cervical scrapes from 181 patients (median age 32 years) at high risk for cervical cancer. RESULTS: HPV were detected in the cervical scrapes of 88 of 181 patients (48.6%); nine with non-oncogenic HPV (5.0%) and 79 with oncogenic HPV (43.6%) including 29 coinfections with oncogenic and non-oncogenic HPV. The number of oncogenic HPV infections increased with the presence of high grade lesions: 95.8% of the cervical scrapes from patients with high grade lesions contained oncogenic HPV compared with 32.1% of the specimens from patients without any lesions detectable by colposcopy and/or by cytological examination of the cervical smears. Moreover, 60% of cervical scrapes exhibiting low grade lesions contained oncogenic HPV. CONCLUSIONS: This test is simple, specific, sensitive, safe, fast, reproducible, and easy to use in routine practice. Thus, it is possible to detect simultaneously on a simple cervical scrape, two kinds of HPV--oncogenic and non-oncogenic--in just two microplate wells with non-isotopic oligoprobes.

Adult↗
PubMed1998

Hybrid capture II, a new sensitive test for human papillomavirus detection. Comparison with hybrid capture I and PCR results in cervical lesions.

AIM: To test a new assay for the detection of human papillomavirus (HPV) DNA, hybrid capture II (HC II), compared with the previous commercialized hybrid capture I (HC I) and polymerase chain reaction (PCR) results on cervical scrapes from fresh cone excision biopsy samples. METHODS: The three methods were used on cervical scrapes from 42 fresh cone excision biopsy samples. There were nine metaplastic and inflammatory lesions, five low grade lesions, and 28 high grade lesions. PCR was performed using the general primers GP5+/GP6+. The viral load of high risk HPV DNA was estimated by the ratio of relative light units to positive control values in the samples. RESULTS: The sensitivity of HC I for the detection of high grade lesions was 71.4%, while it was 92.8% for HC II and 96.4% for the PCR. Considering only the absence of detectable cervical in situ neoplasia, the specificity was 88.9% for HC I, 66.7% for HC II, and 66.7% for PCR. With HC II, for a ratio of cervical sample to normal control of > 200, the sensitivity for the detection of high grade lesion was only 34.6% with a specificity of 66.7%. CONCLUSIONS: HPV detection with the HC II assay is more sensitive than the previous HC I and represents a more convenient and easier test than PCR for routine use. Nevertheless the viral load estimated with this test cannot be a reliable predictive indicator of high grade lesions.

Cervix Uteri↗
PubMed1997

Expression of matrix metalloproteinases and their inhibitors in human bronchopulmonary carcinomas: quantificative and morphological analyses.

The expression of various matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) in 88 primary bronchopulmonary cancers and in 13 neighbouring pulmonary parenchyma samples was quantified by Northern-blot analysis, and morphologically examined by in situ hybridization and immunohistochemistry in order to evaluate the involvement of MMPs in the pathophysiology of these carcinomas and to look for potential markers of aggressivity of lung tumours. Northern-blot analysis showed that the predominantly expressed MMPs in bronchopulmonary cancers were gelatinase A (66%), its activator MT1-MMP (membrane-type-1 matrix metalloproteinase) (56%) and stromelysin-3 (61%). MMP expression frequencies and mRNA levels increased progressively with malignant phenotype, lack of differentiation and TNM stage of the tumours, whereas TIMP expression decreased very early during tumour progression. Moreover, the principal MMPs were significantly co-expressed in primary tumours, suggesting their co-regulation. Morphological studies revealed the expression of MMPs and TIMPs essentially in stromal cells in close contact with tumour clusters. These results indicate that tumour progression in bronchopulmonary carcinomas implies a progressive disruption of the MMP/TIMP balance leading to an excess of several MMPs that act in concert in vivo. Furthermore, the fact that stromal cells are the principal source of MMPs emphasizes the close cooperation between host cells and cancer cells in tumour invasion.

Blotting, Northern↗
PubMed1997

Distribution of a1(IV) and a3(IV) chains of type IV collagen in lung tumours.

Tumour invasion is associated with strong remodelling of the extracellular matrix, including the basement membrane (BM). The major structural component of BMs is type IV collagen, which is composed of an association of three a chains. In this study, the distribution of the a1 and a3 chains in both normal and neoplastic lung tissues has been examined by immunohistochemistry, using specific monoclonal antibodies. In normal tissues, the a1(IV) chain was found in all BMs, whereas the a3(IV) chain was only found in alveolar BMs. In 36 lung tumours, the a1(IV) chain was detected in all cases, with irregular positivity around tumour clusters and in the stroma. It was noteworthy that this stromal distribution was particularly associated with the presence of cancer cells, whatever their invasive properties. In contrast, in 22 tumours out of 36, the a3(IV) chain was only found at the interface between invasive tumour clusters and stroma, with a linear and disrupted pattern. These data show a distinctive distribution of type IV collagen chains in lung tumours, with expression of a1(IV) chain and likely neosynthesis of the a3(IV) chain around some invasive tumour clusters. The results suggest the involvement of these BM components in the process of tumour invasion.

Antibodies, Monoclonal↗
PubMed1997

Expression of stromelysin-3 in the human placenta and placental bed.

Human placentation is mediated by fetal trophoblastic cells which penetrate into the decidualized uterine endometrium. Trophoblast invasion requires the precisely regulated secretion of specific proteinases able to degrade the endometrial basement membranes and extracellular matrix. To document further the involvement of these proteinases during human placentation, we evaluated in vivo the expression of stromelysin-3, a member of the metalloproteinase family, during the first and third trimesters of pregnancy, by means of immunohistochemistry, in situ hybridization and Northern blot analysis. Human extravillous trophoblasts invading the maternal decidua produced stromelysin-3 during both, the first and third trimesters of pregnancy, but to a lesser extent during the latter. In floating villi, stromelysin-3 expression was restricted to the syncytiotrophoblasts that line intervillous vascular spaces. In conclusion, stromelysin-3 is expressed by differentiated, non-proliferative villous and extravillous trophoblastic cells in early and late placental beds and villi, and its pattern of expression evolves during pregnancy. Our observations suggest that stromelysin-3 could play a role in human placentation.

Blotting, Northern↗
PubMed1997

Induction of membrane-type matrix metalloproteinase 1 (MT1-MMP) expression in human fibroblasts by breast adenocarcinoma cells.

Membrane-type matrix metalloproteinase 1 (MT1-MMP) has been recently described as an activator of proMMP-2 (MMP-2) which is involved in tumor invasion. We have shown by in situ hybridization that MT1-MMP is produced by stromal cells in close contact to preinvasive and invasive tumor cells of breast carcinomas. Of particular interest was the observation that some fibroblasts express this enzyme in focal areas in preinvasive lesions, suggesting that particular tumor cells may stimulate fibroblasts to produce MT1-MMP. We have therefore compared the ability of two different breast cancer cell lines, one non-invasive (MCF7) and one invasive (MDA-MB-231) to stimulate MT1-MMP production in human fibroblasts with consequent proMMP-2-activation. The MDA-MB-231 conditioned medium induced MT1-MMP mRNAs in human fibroblasts and a parallel activation of proMMP-2 whereas MCF7 conditioned medium did not have any effect. These results suggest the existence of soluble factor(s) secreted by invasive or some preinvasive breast tumor cells which stimulate fibroblasts to produce and activate MMPs, and emphasize the cooperation between cancer and stromal cells in tumor invasion.

Blotting, Northern↗
PubMed1997

Expression of c-ets-1 mRNA is associated with an invasive, EMT-derived phenotype in breast carcinoma cell lines.

We have previously observed in vitro that some stromal proteinases (MMP-2, MT1-MMP) were expressed or activated by invasive carcinoma cell lines exhibiting mesenchymal features, presumably acquired through an epithelial to mesenchymal transition (EMT). To examine the potential contribution of c-ets-1 to this phenotype, we have compared here the expression of c-ets-1 with invasiveness in vitro and expression of vimentin, E-cadherin, uPA, MMP-1 and MMP-3 in a panel of human breast cancer cell lines. Our results clearly demonstrate an association between c-ets-1 expression and the invasive, EMT-derived phenotype, which is typified by the expression of vimentin and the lack of E-cadherin. While absent from the two non-invasive, vimentin-negative cell lines, c-ets-1 was abundantly expressed in all the four vimentin-positive lines. However, we could not find a clear quantitative or qualitative relationship between the expression of c-ets-1 and the three proteinases known to be regulated by c-ets-1, except that when they were expressed, it was only in the invasive c-ets-1-positive lines. UPA mRNAs were found in three of the four vimentin-positive lines, MMP-1 in two of the four, and MMP-3 could not be detected in any of the cell lines. Intriguingly, MDA-MB-435 cells, which exhibit the highest metastatic potential of these cell lines in nude mice, expressed vimentin and c-ets-1, but lacked expression of these three proteinases, at least under the culture conditions employed. Taken together, our results show that c-ets-1 expression is associated with an invasive, EMT-derived phenotype in breast cancer cells, although it is apparently not sufficient to ensure the expression of uPA, MMP-1 or MMP-3, in the vimentin-positive cells. Such proteases regulation is undoubtedly qualified by the cellular context. This study therefore advances our understanding of the molecular regulation of invasiveness in EMT-associated carcinoma progression, and suggests that c-ets-1 may contribute to the invasive phenotype in carcinoma cells.

Breast Neoplasms↗
PubMed1997

MT1-MMP correlates with MMP-2 activation potential seen after epithelial to mesenchymal transition in human breast carcinoma cells.

We have previously reported that human breast carcinoma (HBC) cell lines expressing the mesenchymal intermediate filament protein vimentin (VIM+) are highly invasive in vitro, and highly metastatic in nude mice when compared to their VIM- counterparts. Since only VIM+ cell lines can be induced to activate matrix metalloproteinase-2 (MMP-2) upon stimulation with Concanavalin A (Con A), we have examined here membrane type 1 MMP (MT1-MMP), a cell surface activator of MMP-2. Northern analysis reveals baseline expression of MT1-MMP in five of the six VIM+ cell lines studied (MDA-MB-231, MDA-MB-435, BT-549, Hs578T, MCF-7(ADR)), each of which showed variable activation of exogenous MMP-2 after treatment with Con A. In contrast, the four VIM-, poorly invasive HBC cell lines studied (MCF-7, T47D, MDA-MB 468, ZR-75-1) lacked baseline MT1-MMP mRNA expression, and showed no induction of either MT1-MMP expression or MMP-2-activation with Con A. Such differential MT1-MMP expression was confirmed in vivo using in situ hybridization analysis of nude mouse tumor xenografts of representative cell lines. Western analysis of the MDA-MB-231 cells revealed baseline membrane expression of a 60 kDa species, which was strongly induced by Con A treatment along with a weaker band co-migrating with that from MT1-MMP-transfected COS-1 cells (63 kDa), presumably representing latent MT1-MMP. MT1-MMP immunofluorescence strongly decorated Con A-stimulated MDA-MB-231 cells in a manner consistent with membranous staining, but did not decorate the unstimulated MDA-MB-231 cells or MCF-7 cells under either condition. Collectively, the results suggest the constitutive production of active MT1-MMP which is unavailable for either MMP-2 activation or immuno-decoration until Con A treatment. Since VIM expression arises by virtue of the so-called epithelial to mesenchymal transition (EMT) in invasive embryonic epithelia, we propose that this represents a major metastasis mechanism in breast carcinomas. MT1-MMP on the surface of such 'fibroblastoid' carcinoma cells may mediate a paracrine loop for the utilization of stromally produced MMP-2, and contribute to the poorer survival associated with VIM+ breast carcinomas.

Animals↗
PubMed1997

Simultaneous effects of aneuploidy and oncogenic human papillomavirus on histological grade of cervical intraepithelial neoplasia.

OBJECTIVE: To investigate whether ploidy and oncogenic human papillomavirus types can be correlated with the histological grade of cervical intraepithelial neoplasia (CIN) in the same tissue sections. DESIGN: Histological data were obtained from 292 dysplastic lesions of the cervix and classified according to the CIN and the Bethesda terminologies. The samples were analysed using Feulgen-stained image analysis cytometry for ploidy and Human papillomaviruses DNA typing by in situ hybridisation, respectively. SETTING: Colposcopy Clinic at Alfred Fournier Institute, Paris. POPULATION: Three hundred and forty women referred for an abnormal cervical smear. RESULTS: The ploidy data strongly segregate high grade from low grade squamous intraepithelial lesions (aneuploidy 78% versus 21%; P < 0.0001). There was a significant association between aneuploidy and the severity of the lesions (94% for CIN 3, 55% for CIN 2 and 14% for CIN 1; P < 0.0001). Both classifications showed a significant association of histological grade with oncogenic human papillomavirus types (HPV 16-18-33; 20% in low grade and 78% in high grade squamous intraepithelial lesions, 31% and 75% in CIN 1 and CIN 3, respectively; P < 0.0001). The simultaneous effects of these viruses and ploidy demonstrate an association in aneuploid cells between the presence of oncogenic human papillomavirus types and histological grade (76% and 18% in high and low grade squamous intraepithelial lesions, respectively; P < 0.0001). Such an association was not observed in diploid cells (20% in both low and high grade squamous intraepithelial lesions). CONCLUSIONS: High risk human papillomavirus types do not exert and an independent effect on the histological grade of cervical intraepithelial neoplasia.

Aneuploidy↗
PubMed1997

Tumor collagenase stimulatory factor (TCSF) expression and localization in human lung and breast cancers.

Tumor cell-derived collagenase stimulatory factor (TCSF) stimulates in vitro the biosynthesis of various matrix metalloproteinases involved in tumor invasion, such as interstitial collagenase, gelatinase A, and stromelysin 1. The expression of TCSF mRNAs was studied in vivo, using in situ hybridization and Northern blotting analysis, in seven normal tissues and in 22 squamous cell carcinomas of the lung, and in seven benign proliferations and in 22 ductal carcinomas of the mammary gland. By in situ hybridization, TCSF mRNAs were detected in 40 of 44 carcinomas, in pre-invasive and invasive cancer cells of both lung and breast cancers. TCSF mRNAs and gelatinase A mRNAs were both visualized in the same areas in serial sections in breast cancers, and were expressed by different cells, tumor cells, and fibroblasts. The histological results were confirmed by Northern blot analysis, which showed a higher expression of TCSF mRNAs in cancers than in benign and normal tissues. These observations support the hypothesis that TCSF is an important factor in lung and breast tumor progression.

Antigens, CD↗