Biomedical subjects

T Maudelonde

Publications and source records attributed to T Maudelonde.

At least 37 records · Page 2Linked to original sources

PubMed1996

Identification of prometalloproteinase-3 as a major protein secreted by human endometrial fibroblasts and inhibited by coculture with trophoblast cells.

To assess endometrial fibroblast-cytotrophoblast interactions, we used a coculture system allowing analysis of the potential cell morphology modifications and protein secretion variations possibly involved in endometrial invasion arrest. Stromal cells and cytotrophoblasts were isolated from endometrial biopsies and first-trimester placental villi, respectively. In our culture conditions, a 57-kDa protein that was secreted by cultured fibroblasts but was absent in the 4-day coculture medium was found to be identical to prometalloproteinase-3 (proMMP-3) through determination of amino acid sequences of NH2-terminal and internal peptides. Northern blotting analysis of endometrial fibroblast total RNA showed a 38.6% metalloproteinase-3 (MMP-3) mRNA inhibition by 4-day 10(-6) M R5020 treatment. Inhibition of proMMP-3 secretion was weak when cytotrophoblasts were cultured for 4 days in a polycarbonate membrane insert over cultured fibroblasts without possible cell contact in spite of high levels of progesterone produced by cytotrophoblasts. Furthermore, cytotrophoblasts cultured on a monolayer of endometrial fibroblasts became syncytia, and most of the fibroblasts were decidualized. The closeness of the two cell types allowed paracrine relationships that might facilitate the progesterone action. Since MMP-3 is known to activate collagenases, inhibition of its secretion by cell contact might be a mechanism of invasion arrest for trophoblast cell migration.

Amino Acid Sequence↗

PubMed1994

[Steroid hormone receptors].

Steroid receptors belong to a superfamily of hydrosoluble nuclear proteins which regulate transcription of a number of genes. In the absence of hormone, they are bound to proteins which maintain the receptors in an inactive state but prepared for binding with the hormone. In the presence of the hormone, the receptor is activated, which is reflected by modification of its physico-chemical constants and dissociation of associated proteins. This hormone-receptor complex forms a homodimer and binds to DNA at the regulatory regions of the genes involved, which is termed "hormone response element". The receptors are constituted of 5 to 6 domains, each responsible for one or several functions. The hormone binding domain (region E) and DNA binding domain (region C) are the most highly conserved. Progress in the comprehension of the mechanism of action of these receptors has led to the development of antihormones which are important in the treatment of hormone-dependent cancer. With progress in molecular biology, it is now possible to detect mutants of the receptors or their absence in syndromes involving hormonal resistance.

Humans↗

PubMed1994

[Estrogen receptors and breast cancer].

Activation of oestrogen receptor has a promoting effect in early steps of mammary carcinogenesis. Loss of oestrogen receptor, or of its functionality is associated to more aggressive and hormone unresponsive breast cancers. Anti-oestrogens are antiproliferative agents inhibiting oestrogens and growth factors action by binding to the oestrogen receptor. Assay of oestrogen and progesterone receptors, in the cytosol of primary breast cancer provides information on the differentiation and prognosis of the tumour and on the efficacy of endocrine treatment. Several oestrogen receptor variants have been detected in breast cancer, but their significance remains hypothetical. They could act in a positive constitutive fashion (e.g. anomaly of the hormone binding site with conservation of the DNA binding site) or be nonfunctional (e.g. anomaly of the DNA binding domain and or transactivation). They are often associated in the tumor with normal wild type receptors and could decrease their activity by forming nonfunctional heterodimers.

Breast Neoplasms↗

PubMed1994

Cathepsin D cytosolic assay and immunohistochemical quantification in human prostate tumors.

We quantified cathepsin D by immunoradiometric assay (IRMA) and quantitative immunohistochemistry in fifteen human prostate cancers, seventeen BPH, and nine normal prostates. The cytosolic cathepsin D concentration was higher in prostatic carcinoma (mean: 31.5 pmol/mg cytosol proteins; range: 10.2-66.2) than in normal prostate (16.0 pmol/mg cytosol proteins; 7.2-25.5; P = 0.01). Prostatic hyperplasia showed intermediate values (20.2 pmol/mg cytosol proteins; 7.6-33.9). Immunostaining of cathepsin D and prostatic acid phosphatase on serial frozen sections of prostate tissues was only observed in glandular epithelial cells. Immunostaining was quantified by computer-assisted image analysis as an quantitative immuno-cytochemical score (QIC score) expressed in arbitrary units (A.U.). QIC scores for cathepsin D were dispersed and had a tendency to be higher in benign prostatic hyperplasia (mean: 178.3 A.U.; range: 95-297) compared to normal prostate (85.2 A.U.; 2-173 P < 0.01) and prostatic carcinoma (90.0 A.U.; 21-179 P = 0.0002). Prostatic cathepsin D levels in cytosols or immunostaining sections were independent of other clinicobiological parameters.

Acid Phosphatase↗

PubMed1994

Cathepsin D immunostaining in paraffin-embedded breast cancer cells and macrophages: correlation with cytosolic assay.

High cathepsin D (cath-D) concentration in breast cancer cytosol is associated with increased risk of metastasis. To specify the relative contribution of the different cells types responsible for cath-D level in cytosol, we validated semiquantitative cath-D immunoperoxidase staining on formalin-fixed, paraffin-embedded sections, using the M1G8 monoclonal antibody, one of the two antibodies of the cytosolic assay. Using computer-aided image analysis, cath-D level in cancer cells was estimated by integrating both staining intensity in each cell and proportion of stained cells. We confirmed on 41 primary breast cancers a higher expression of cath-D in cancer cells compared with peritumoral mammary glands. Cancer cell staining was mostly in lysosomes and for some invasive ductal carcinomas in large vesicles corresponding to phagosomes. Lymphocytes and fibroblasts were not or were only weakly stained. Macrophages also were stained for cath-D, generally on the periphery of the tumor area. The cytosolic cath-D level was correlated with cath-D expression in cancer cells (r = .76; P = 1 x 10(-4)) rather than with the number of macrophages in the tumor (r = .29; P = .09), as determined by use of the specific anti-CD68 antibody. There was a significant increase in the tissue cath-D level in tumors containing large vesicles compared with tumors without large vesicles. This approach provides a means to separately estimate the prognostic significance of cath-D expression in cancer cells and macrophages when evaluating risk of metastasis.

Breast Neoplasms↗

PubMed1994

In vivo stimulation by tamoxifen of cathepsin D RNA level in breast cancer.

We have previously shown that 3 weeks of treatment with tamoxifen, of patients with primary breast carcinomas, increased cytosolic cathepsin D protein in oestrogen receptor (ER) positive tumours [Maudelonde et al., Cancer 1989, 63, 1265-1270]. In order to investigate the mechanism of this increase and to eliminate a transient flare-up effect, we semi-quantified cathepsin D RNA levels by in situ hybridisation in 32 breast carcinomas from patients treated with tamoxifen for 3 weeks prior to surgery and in 35 breast cancer patients receiving no tamoxifen. We found that tamoxifen increased cathepsin D RNA level regardless of the ER status of the tumours. In ER positive tumours, tamoxifen increased the cathepsin D RNA level to the same extent as cytosolic cathepsin D protein but not in ER negative tumours. The induction of cathepsin D RNA by tamoxifen in ER positive tumours was probably due to its agonist activity, also observed in vitro in breast cancer cell lines. These results suggest that the cathepsin D gene is inducible by oestrogens in ER positive breast cancer as it is in breast cancer cell lines.

Aged↗

PubMed1993

Correlation between mannose-6-phosphate/IGFII receptor and cathepsin D RNA levels by in situ hybridization in benign and malignant mammary tumors.

We evaluated levels of mannose-6-phosphate/insulin growth factor-II receptor (M6P/IGFII-R) RNA in 37 breast cancer tumors by quantitative in situ hybridization using a computer-aided image analyzer and compared them to cathepsin D RNA and protein levels in the same tissues. Breast cancer cells expressed more cathepsin D and M6P/IGFII-R RNA than fibroblasts in the same tumors. We found a significant increase of cathepsin D RNA (P = 1 x 10(-5)) and M6P/IGFII-R RNA (P = 0.02) in breast cancer cells compared to epithelial cells of benign mastopathies. There was a positive correlation (r = 0.65; P = 1 x 10(-5)) between M6P/IGFII-R and cathepsin D RNA levels measured on serial sections. This contrasted with the inverse relationship of these 2 RNA species in breast cancer cell lines where estrogen down-regulates M6P/IGFII receptor RNA levels. Moreover, in vivo we found no correlation between the M6P/IGFII-R RNA level and menopausal or estrogen receptor status, suggesting that the in vivo regulation of M6P/IGFII-R RNA differs from its in vitro regulation in cell lines. The M6P/IGFII-R RNA level was not correlated with cathepsin D status, histological grade, and tumor size but was significantly higher in lymph node-positive tumors (P = 0.047). The M6P/IGFII-R could therefore be an additional parameter to predict aggressive breast cancers, complementing cathepsin D assays and other more classical prognostic parameters.

Breast Diseases↗

PubMed1993

A prospective study of the prognostic value of cathepsin D levels in breast cancer cytosol.

BACKGROUND: Cathepsin D is a lysosomal protease overexpressed and abnormally secreted in most breast cancer cells. Several retrospective clinical studies have shown that cathepsin D is an independent prognostic factor in breast cancer that is associated with a higher risk of recurrence and a shorter overall survival. METHODS: To the authors' knowledge, this is the first prospective study in which the prognostic value of cathepsin D was studied in 123 patients with primary breast cancer who were followed for 5 years between March 1985 and December 1990. Cathepsin D concentrations in breast cancer cytosol were measured using a solid-phase sandwich immunoenzymatic assay. The most significant prognostic factors were identified by multivariate analysis using the Cox proportional-hazards method. RESULTS: The median value of cathepsin D was 20.8 pmol/mg of protein, which was approximately half than the median value found in subsequent assays done using a commercially available kit and reported in most retrospective studies. The cathepsin D status or level was correlated only with axillary lymph node involvement. A univariate analysis showed that high levels of cathepsin D (> 20 pmol/mg of protein) were correlated with a higher risk of recurrence and a shorter overall survival (P < 0.01 and P < 0.03, respectively). Using multivariate analysis, a high cathepsin D level, a negative progesterone receptor status, and lymph node involvement were the most important factors for predicting relapse-free survival (P = 0.02, P < 0.01, and P < 0.05, respectively). The cathepsin D level had prognostic value in patients with node-positive disease (P = 0.001) and appeared to be particularly useful in association with the progesterone receptor status by isolating a high-risk subgroup of patients (high cathepsin D level; negative progesterone receptor status). CONCLUSIONS: This first prospective study confirmed the prognostic value of the cathepsin D level in association with other major prognostic factors. The next step will be to determine whether the subset of patients with high cathepsin D levels would benefit from adjuvant therapy.

Adult↗

PubMed1993

Immunoradiometric assay of pro-cathepsin D in breast cancer cytosol: relative prognostic value versus total cathepsin D.

In breast cancer cell lines, the maturation of pro-cathepsin D into enzymatically active cathepsin D is altered, leading to its increased secretion. In order to specifically assay pro-cathepsin D (52 kD form) in breast cancer cytosol, we monitored a solid phase sandwich radioimmunoassay using D9H8 and D7E3 monoclonal antibodies raised against human pro-cathepsin D from MCF7 cells. Pro-cathepsin D was assayed in 108 primary breast cancer cytosols in which total cathepsin D was previously found to be correlated with metastasis. Pro-cathepsin D concentrations were found to be correlated with total cathepsin D and with lymph node invasion, and was slightly higher in premenopausal patients. By contrast, Cox multiparametric analysis showed that pro-cathepsin D status had no prognostic value for survival, or metastasis free survival contrary to total cathepsin D status. This first study shows the technical validity of the pro-cathepsin D assay but indicates that it has less value as a prognostic marker than total cathepsin D. This study also shows that the proportion of pro-cathepsin D recovered in vivo (1-6%) is much less than that produced in cell lines and suggests that the secreted pro-enzyme might be activated in the tumour extracellularly or following its reinternalisation.

Biomarkers, Tumor↗

PubMed1993

Potential value of increased MYC but not ERBB2 RNA levels as a marker of high-risk mastopathies.

MYC and ERBB2 levels were measured in 38 benign breast diseases using a semiquantitative in situ hybridization technique. Mean levels of MYC and ERBB2 gene expression in benign tissues were similar to those measured in 15 breast cancers with no amplification at the loci concerned. Interestingly, MYC but not ERBB2 RNA levels were increased (t-test, P = 0.03) in benign mastopathies of patients with a first-degree (mother/sister) family history (FH) of breast cancer. Among patients without a first-degree FH, MYC RNA levels were significantly higher (t-test, P = 0.02) during the follicular (preovulatory) than the luteal (post-ovulatory) phase and also significantly higher than levels observed in patients with no menstrual cycle (peri- or postmenopausal) (P = 0.004), indicating an in vivo hormonal regulation of MYC. After exclusion of the first-degree FH patients a higher MYC expression was detected in atypia than in other histological types at the follicular but not at the luteal phase, suggesting an increased sensitivity of these high-risk lesions to estrogens. We propose that in addition to a family history and proliferative atypia, elevated MYC RNA levels during the post-ovulatory phase could potentially be used as a marker of the risk of developing breast cancer. The increase in MYC RNA in high-risk breast diseases also suggests that MYC deregulation might be involved in the early stages of mammary carcinogenesis.

Breast Diseases↗

PubMed1992

Immunostaining of cathepsin D in breast cancer: quantification by computerised image analysis and correlation with cytosolic assay.

Cathepsin-D (cath-D) was quantified in 34 breast cancer specimens by immunohistochemical staining of frozen sections with a computer image analysis and the results were compared with the corresponding cytosolic assay. Cath-D concentrations varied from 0 to 420 arbitrary units (AU). Tumour cells were more intensely stained than peritumoral tissue with the D7E3 mouse monoclonal antibody than with rabbit polyclonal antibodies. There was a good correlation (r = 0.80) between cath-D values obtained either by immunohistochemistry with D7E3 antibody or by cytosolic immunoenzymatic assay. However, with a cut-off of 50 AU, 3 out of 25 patients had higher immunohistochemical values and 2 had higher cytosolic values. Therefore, quantification of cath-D concentration in tissue section by immunostaining and a computerised image analyser, which is the only technique available for small tumours, should provide similar prognostic information to that obtained by assaying cath-D in the cytosol.

Animals↗

PubMed1992

Estradiol stimulates cell growth and secretion of procathepsin D and a 120-kilodalton protein in the human ovarian cancer cell line BG-1.

Ovarian cancers are highly invasive. In a first attempt to define the hormones and factors involved in the control of tumor invasion and metastasis, we have used the human ovarian cancer cell line BG-1 which contains both estrogen and progesterone receptors. Protein synthesis and secretion was assayed by [35S]methionine incorporation and polyacrylamide gel electrophoresis followed by fluorography. Three responses to estradiol were found: 1) procathepsin D secretion was increased, whereas the corresponding intracellular proteins were not significantly affected; 2) an abundant but nonidentified 120-kilodalton (kDa) estrogen-induced secreted glycoprotein, different from CA125, was detected for the first time; and 3) the number of cells as determined by DNA assay was markedly stimulated, reaching a higher level of confluency. The antiestrogen OH-tamoxifen was weakly agonist at low concentrations to stimulate cell growth but was a pure antagonist on the 120-kDa protein. The steroid specificity of these responses strongly suggests that they are mediated by the estrogen receptor. We conclude that cathepsin D secretion is specifically stimulated by estrogen in this ovarian cancer cell line as it is in estrogen receptor-positive breast cancer cells. Both cathepsin D and a newly described 120-kDa secreted glycoprotein are potential markers of hormone responsiveness and/or aggressiveness which deserve to be further studied in clinical ovarian cancers.

Cathepsin D↗

PubMed1992

Cathepsin D concentration in breast cancer cytosols: correlation with disease-free interval and overall survival.

Cathepsin D (CD) is an aspartyl protease implicated in cancer metastasis. In this study of 331 patients, we show that patients with primary breast carcinomas containing high concentrations of CD have a significantly shorter disease-free interval (chi-square = 4.28, P < 0.05) and overall survival (chi-square = 7.7, P < 0.01) than patients with low concentrations. CD as a prognostic marker for overall survival was equally valuable for women younger (chi-square = 4.39, P < 0.05) and older (chi-square = 3.97, P < 0.05) than 50 years. CD was also a significant prognostic marker for overall survival within the estradiol receptor (ER)-positive subgroup of patients (chi-square = 5.79, P < 0.025), but not in the ER-negative subgroup. Patients with tumors containing high concentrations of CD and low concentrations of ER had shorter disease-free intervals (chi-square = 15.1, P < 0.001) and lower overall survival (chi-square = 20.9, P < 0.001) than patients with high concentrations of ER but low concentrations of CD.

Biomarkers, Tumor↗

PubMed1991

Progestin treatment depresses estrogen receptor but not cathepsin D levels in needle aspirates of benign breast disease.

We studied the effect of a progestin (lynestrenol) on estrogen receptors (ER) and cathepsin D (cath-D) levels immunochemically in successive fine needle aspirates of benign breast disease. Fibrocystic disease was the main pathology (43 out of 47 patients). Thirty-one patients were treated with 10 mg of lynestrenol daily from the fifth to the twenty-fifth day of the menstrual cycle for 1 to 3 months. Sixteen untreated patients were used as controls. Lynestrenol significantly decreased the percentage of ER stained cells. This is in agreement with the antiestrogenic effect of progestin and, for the first time, indicates that in vivo progestin may decrease the stimulatory effect of estrogens on mammary cells by decreasing their estrogen receptor content. No effect of progestin on cath-D level was found throughout the whole population. However, this level varied more between aspirates of each patient in the treated group than in the control group, suggesting heterogeneity in patient responses to progestin. Since cath-D may have a role in carcinogenesis, clinical follow-up of these patients and more detailed studies are required to determine whether this progestin-challenge test has any value for detecting high risk mastopathies and for predicting effectiveness of treatment.

Adult↗

PubMed1991

Increased plasma cathepsin D concentration in hepatic carcinoma and cirrhosis but not in breast cancer.

Using a sandwich enzyme-linked immunoassay, plasma total cathepsin D concentration was assayed in 40 breast cancer patients and 84 patients with various liver diseases and compared to that of 52 normal subjects. There were no significant variations found in breast cancer patients related to tumor size, node invasiveness or metastases. In normal women, cathepsin D levels were slightly but not significantly increased in the luteal phase and in pregnancy. By contrast, plasma cathepsin D concentration was significantly increased in 70-75% of patients with liver disease (cirrhosis, hepatocarcinoma, hepatitis), but not in those with liver steatosis. Cathepsin D was independent of most of the plasma hepatic function tests and was correlated with alpha-fetoprotein in cirrhosis and with alpha-fucosidase in primary hepatocellular carcinoma. We conclude that plasma cathepsin D is not a useful marker in breast cancer. However, since the cellular level of this protease is associated with risk of metastasis in breast cancer, clinical follow-up will be required to test whether high cathepsin D plasma concentration has any prognostic value in liver cirrhosis and primary hepatocarcinoma.

Breast Neoplasms↗

PubMed1991

Decrease of c-erbB-2 and c-myc RNA levels in tamoxifen-treated breast cancer.

The c-myc, c-erbB-2, hst and int-2 oncogenes are frequently amplified and/or overexpressed in human breast carcinomas. We studied the effect of tamoxifen on RNA levels of these oncogenes in 19 breast cancer patients treated for 3 weeks prior to surgery as compared with 22 control patients. RNA levels were measured by in situ hybridization coupled with computer-aided quantification. c-myc and c-erbB-2 expression was high in the control population (mean values: 23.4 and 29.1 grains/cell respectively) and significantly decreased in the tamoxifen-treated population (mean values: 14.6 and 7.4 grains/cell respectively) (P = 0.018, P = 0.003 respectively); hst and int-2 RNA levels were low (2-6 grains/cell) and not significantly altered by the treatment. There was a correlation between gene amplification and expression for c-erbB-2 (P = 0.0005) and hst (P = 0.02) in the control population. Elevated c-erbB-2 RNA level was correlated with the absence of estrogen (P = 0.02) or progesterone (P = 0.05) receptors. In the ER+ population, the tamoxifen-treated group had significantly lower c-myc expression levels than the control group (P = 0.04) which is in agreement with the estrogen induction of c-myc in ER+ T47D cell line and its inhibition by antiestrogens. Surprisingly, c-erbB-2 expression in the tamoxifen-treated group was significantly diminished in the ER- (P = 0.02) and PR- (P = 0.01) populations. This effect was not observed in the ER- BT474 cell line. These results suggest that in vivo tamoxifen decreases c-myc and c-erbB-2 RNA levels in breast cancer cells via two different mechanisms. To our knowledge this is the first evidence of in vivo down regulation of a gene by tamoxifen in ER- breast cancer cells.

Adult↗

PubMed1991

[Synthetic steroid anti-hormones].

Steroid antagonists are competitive inhibitors of the corresponding hormone for binding to its specific receptor. Their antagonist action depends on their metabolism and on partial antagonist action depends on their metabolism and on partial agonist effect which is variable with the species, the tissue or regulated gene. Their action in tumoral proliferation is exerted via autocrine, paracrine or endocrine pathways. In addition they may have their own effect mediated by the corresponding steroid receptor (ex: antiestrogen, antiprogestin...) or by specific binding sites (ex: tamoxifen binding sites). They are prescribed in the treatment of hormone dependent cancers. Some sex-steroid antagonists are largely used in adjuvant therapy because of their good clinical tolerance. Study of their interest as a chemopreventive agent in cancer is actually in progress. Pure antihormones could be highly interesting in advanced cancers but they might have secondary effects in long term therapy. In spite of available steroid antagonists have widely proven to be valuable tools in the treatment of breast cancer, the ideal anti-steroid compound should be pure antagonist in the considered target tissue and partial antagonist in the others.

Animals↗

PubMed1991

Cathepsin D concentration in breast cancer cytosols: correlation with biochemical, histological, and clinical findings.

Cathepsin D (CD, EC 3.4.23.5) is a lysosomal protease induced by estrogen in certain estrogen receptor (ER)-positive breast cancer cell lines but produced constitutively by ER-negative cell lines. Our aims in this investigation were to study the distribution of CD in human breast cancers and to relate its concentrations to various biochemical, histological, and clinical characteristics. The concentrations of CD were significantly higher in breast carcinomas than in either normal breast tissues or benign breast tumors. In primary carcinomas, CD concentrations did not correlate with the concentrations of ER or with the estrogen-inducible protease t-PA. However, CD concentrations did correlate weakly but significantly with both UK-PA antigen and UK-PA activity. Also, CD concentrations did not correlate with either tumor stage or axillary node status but did correlate significantly with tumor grade. Patients with cancers containing high concentrations of CD had a significantly shorter overall survival than did patients with low concentrations of the enzyme.

Breast Neoplasms↗