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M F Pichon

Publications and source records attributed to M F Pichon.

At least 37 records · Page 2Linked to original sources
PubMed1992

Oestrogen receptor negative-progesterone receptor positive phenotype in 1,211 breast tumours.

From 1,211 breast cancers, 15 oestrogen receptor (ER) negative-progesterone receptor (PgR) positive breast cancers by conventional dextran coated charcoal steroid binding assays in cytosol were reassessed using Elisa techniques with monoclonal antireceptors antibodies in the cytosolic and nuclear fractions, and immunocytochemistry on cryostat sections. Three categories of results were found in this series. Two tumours were false negative ER due to receptor sites occupancy by hormonal contraceptive treatment. A second group of ten tumours, with high PgR concentrations and immunoreactive ER, corresponds to non ER-binding forms of receptors. One PgR positive tumour was found to be devoid of PgR by using monoclonal antiPgR antibodies might contain a progesterone binding cyst protein. Only two tumours were found to be true ER negative-PgR positive by all methods. This rare phenotype deserves further study of the regulation of the PgR gene.

Adult↗
PubMed1990

Monoclonal antibodies against native ant denatured forms of estrogen-induced breast cancer protein (BCEI/pS2) obtained by expression in Escherichia coli.

Several vectors were used to express the complementary DNA for breast cancer estrogen-induced protein BCEI (also called pS2) in Escherichia coli. The best results were obtained by using the pUR 290 expression vector after deletion of the sequence encoding the signal peptide of the protein. In these conditions, beta-galactosidase-BCEI/pS2 fusion protein accounted for approximately 20% of total proteins in bacterial extracts. It was purified by chromatography on DEAE-Trisacryl or by gel electrophoresis and electroelution. Polyclonal antibodies were obtained by immunization of rabbits and goats, and monoclonal antibodies were raised in mice. Two types of monoclonal antibodies were obtained: one class recognized the native protein and was very efficient for the immunoprecipitation and immunopurification of the protein from breast cancer cells; a second class recognized the denatured protein and was especially effective for immunoblot studies. BCEI/pS2 could be detected by immunocytochemistry in breast cancer biopsies using monoclonal antibodies on frozen or paraffin-embedded sections. One of the antibodies (mBCEI11) exhibited high affinity for the protein and could be used at 1.9 micrograms/ml concentration for immunolabeling of histological sections. The mBCEI11 antibody was used in immunoaffinity chromatography to purify the peptide in a single step from culture media of estrogen-treated MCF-7 cells.

Antibodies↗
PubMed1989

Lymphocytic progesterone receptors in normal and pathological human pregnancy.

The progesterone receptor-specific monoclonal antibody (MoAb) mPRI was tested for its reactivity towards peripheral blood lymphocytes (PBL) of 49 healthy pregnant women, nine pregnant women with clinical symptoms of threatened preterm delivery, seven women with recurrent spontaneous abortion, ten women in labour and ten women with spontaneous abortion. Lymphocytes of 12 healthy age-matched non-pregnant volunteers were used as controls. Lymphocytes of nine healthy pregnant women at the 1st trimester of pregnancy and those of two non-pregnant donors were tested for the presence of estrogen and progesterone receptors by enzyme immunoassay. PBL of healthy pregnant women contained significantly more positive cells than those of non-pregnant controls. Furthermore, the number of receptor-containing cells increased in parallel with gestational age. In blood samples drawn during labour, as well as in those obtained from women with spontaneous abortion or clinical symptoms of threatened pre-term delivery, the percentage of positively stained lymphocytes was significantly lower than normal pregnancy values. This was also the case in peripheral blood of pregnant women with a history of recurrent spontaneous abortions.

Abortion, Habitual↗
PubMed1988

Modulation of estrogen receptors by phorbol diesters in human breast MCF-7 cell line.

Treatment of MCF-7 cells with 12-O-tetradecanoylphorbol 13-acetate (TPA) results in an inhibition of cell proliferation and a reduction in the number of estrogen receptors (ER), shown by binding studies and immunoassay. The decrease in ER concentration induced by phorbol ester derivatives parallels their growth inhibitory effect. Moreover, the estrogen receptor of TPA-resistant RPh4 cells (which are insensitive to the antiproliferative and morphological effects of TPA) is not affected by TPA treatment. The reduction in ER concentration appear to be a specific phenomenon since it contrasted with the 2-fold increase in total cell protein content which included an increase in progesterone receptor (PgR). We also found that addition of TPA does not affect estrogen induction of PgR.

Binding, Competitive↗
PubMed1986

Abbott monoclonal enzyme immunoassay measurement of estrogen receptors in human breast cancer: a European multicenter study.

A new enzyme immunoassay (Abbott ER-EIA Monoclonal) for the determination of estrogen receptor in cytosols from breast tumor specimens has been developed by Abbott Laboratories. To establish the correlation of the results from this new technique with currently existing steroid binding methods, a multicenter study was conducted in eight European laboratories. All participants followed the same protocol consisting of a familiarization phase, a proficiency evaluation, and a comparison of existing steroid binding methods with the new immunoassay using panel samples and clinical specimens. ER-EIA was compared with the multipoint dextran coated charcoal assay in six laboratories, four of which followed the EORTC protocol; of the remaining two laboratories, one used a single saturating dose assay, the other an isoelectric focusing assay. The results show no significant difference between reducing agents when used in the ER-EIA. Reproducibility for the immunoassay (interassay coefficient of variation, 6%, interlaboratory coefficient of variation, 11-19%) was somewhat better than that for the steroid binding methods (interlaboratory coefficient of variation, 12-32%). The correlation between the methods was dependent on the origin of the lyophilized specimens. In breast tumor samples, an excellent correlation, (not statistically different from 1) was found between the ER-EIA and the steroid binding method in six laboratories. One laboratory showed a slope of 1.1 for the correlation line; the laboratory using isoelectric focusing showed a slope of 1.9. The mean value determined by the enzyme immunoassay in premenopausal women was 74 fmol/mg cytosol protein, and in postmenopausal women it was 187 fmol/mg cytosol protein with no significant difference in the slope of the correlation line. Results suggest the usefulness of the new standardized enzyme immunoassay for routine use in the clinical laboratory.

Antibodies, Monoclonal↗
PubMed1985

Cloning of a gene expressed in human breast cancer and regulated by estrogen in MCF-7 cells.

Messenger RNAs (mRNAs) were prepared from MCF-7 breast cancer cells grown in the presence of estradiol. Complementary DNAs (cDNAs) were inserted into pBR322 plasmid and a library of 4400 recombinant bacterial clones was prepared. The clones were screened by in situ differential hybridization with cDNAs prepared from RNAs of MCF-7 cells grown either in the presence or absence of estradiol. Several estrogen-induced or estrogen-repressed clones were identified. One of them corresponded to a relatively frequent mRNA (0.8% of recombinant plasmids) of 650 nucleotides. The concentration of this mRNA was increased by estradiol (half maximal induction approximately 0.05 nM) but not by progesterone, dexamethasone, or dihydrotestosterone. Tamoxifen inhibited the effect of estradiol but was devoid of any agonistic activity when administered separately. This messenger was present in biopsies of breast cancer, but not in endometrium or liver. The cloned cDNA was sequenced. An open reading frame was found corresponding to a protein of less than 100 amino acids. A search of data banks showed no identity or marked similarity to previously published DNA or protein sequences, particularly to those of growth factors evoked by some characteristics of the coded polypeptide. The cloned cDNA probe was used to screen a library of Charon 4A phage containing human genomic fragments. Screening of 300,000 phages yielded two different recombinants hybridizing to the cDNA. Southern blot experiments using DNA from recombinant phage, MCF-7 cells, and placenta showed the presence of a unique gene exhibiting a similar restriction pattern in DNAs from malignant and nonmalignant tissues.

Amino Acid Sequence↗
PubMed1984

Relationship between ultrastructure and receptor content of human primary breast cancer.

The ultrastructure of 47 primary breast cancers was studied. For each tumour, the characteristics of approximately 200 malignant cells were examined. Eleven features were scored from 1 to 3 and multivariate analysis showed that seven of these could be used to define an ultrastructural index of differentiation. Differentiation at the ultrastructural level was associated with the presence of steroid receptors. Differentiated tumoral cells contained oestrogen receptor and progesterone receptor in 81.8% and 66.7% of cases, respectively. Poorly differentiated cells contained oestrogen receptors in 50% and progesterone receptor in 14.3% of cases. Comparison of histological grading by the method described by Scarff, Bloom & Richardson with the ultrastructural index of differentiation showed a rather loose correlation which was not significant in this group of 47 patients. The authors conclude that differentiation at tissue or cellular levels yields differing information, only the latter being closely correlated with steroid receptor presence.

Adenocarcinoma↗
PubMed1983

[Quality control of the assay of receptors in human breast tumors].

Many technical problems are encountered when measuring estradiol and progesterone receptors in breast tumors biopsies. They are due to both intrinsic characteristics of the tissue, and to receptors instability. Suggestions are made to establish an internal quality control in each laboratory at the different steps: obtention and storage of biopsies, purity checking of the reagents, control of the assay protocol, and calculations. Several methods to prepare control pools have been proposed. They use either mammary tumors or animal target organs, and stable concentrations of receptors have been obtained by storage in liquid nitrogen or lyophilization. Published studies have demonstrated important interlaboratory variations. These discrepancies might be in part reduced by using the same assay protocol in the different participating laboratories.

Breast Neoplasms↗
PubMed1983

[Hormone receptors and breast cancer prognosis].

Estradiol and progesterone assays in breast cancer have been developed for ten years and their clinical significance investigated in primary and metastatic tumors. The presence of estradiol and/or progesterone receptor is not related to the extension of the disease, the age of the patient or hormonal status. It seems to be related to the grade of histological differentiation. 1) Clear relationship exists between the presence of estradiol receptor and hormone dependency. 2) Estrogen receptor positive tumors demonstrate a more favorable outcome than the estrogen receptor negative one. According to recent data the presence of progesterone receptor is a better criteria than ER for long term pronostic.

Breast Neoplasms↗
PubMed1982

Estradiol and progesterone receptors content and response to norethisterone treatment in advanced breast cancer.

Twenty-six patients with advanced breast cancer and progressive disease were treated by norethisterone. Estradiol and progesterone receptors were measured before starting treatment, and in three cases after 2 to 4.75 months of therapy. Partial remissions (greater than 50% decrease of all lesions) or objective improvements (decrease of 20-50%) were obtained in 7 patients, with a mean duration of 6.7 months. Stabilization of the lesions (no change or decrease of less than 20% in the size of the target lesion) was observed in 7 patients. No clear-cut correlation was found between clinical response and presence in biopsies of estradiol and progesterone receptors. However, absence of response occurred more frequently if tumors did not contain progesterone receptors.

Adult↗
PubMed1981

Thyroid hormone receptors in human breast cancer.

Optimum conditions were established for preparation of nuclei from human breast cancer biopsies. Incubation of nuclei with various concentrations of L-3,3',5-[125I]triiodothyronine showed the presence of three binding systems: a high-affinity binding system (type I) (KD approximately 0.5 micro M); an intermediate-affinity saturable system (type II) (Kd approximately 0.5 micro M)p and a nonsaturable nonspecific system. Salt at high concentrations (0.4 M-KCl) extracted only type I triiodothyronine-binding protein, thus simplifying its study and quantification. Type I binding protein was shown to have the affinity for triiodothyronine and the hormonal specificity usually ascribed to thyroid hormone receptors. Its sedimentation coefficient was 3.6S at 0.4 M KCl. Extractable triiodothyronine receptors was measured in 58 individual biopsies of primary and metastatic breast cancer. It was present in all tumors, but its concentration was highly variable (average, 0.20 pmol/mg DNA; range 0.044 to 0.702). Triiodothyronine receptor concentration was not correlated with age or endocrine status of the patient or with extension or histological grading of the tumor. Moreover, there was no correlation with estradiol and progesterone receptor concentration.

Adult↗
PubMed1980

Estrogen receptors in human pituitary adenomas.

Estrogen-binding proteins were observed in the cytosol of human pituitary adenomas. The Kd for estradiol was 0.44 nM at 0 C, and hormonal specificity was that expected for estrogen receptors. Sucrose gradient sedimentation experiments revealed that receptors from different tumors existed in either the 8S or the 4S form or both. Of the 23 tumors examined, 14 contained estrogen receptors. Receptors were more often present and their concentration was higher in PRL-secreting adenomas (mean +/- SEM, 20.6 +/- 13.4 fmol/mg proteins; 7 determinations) than in GH-secreting adenomas (1.4 +/- 0.8 fmol/mg protein; 9 determinations) and chromophobe tumors (4.1 +/- 1.6 fmol/mg protein; 7 determinations). There was also a correlation between the presence of estrogen receptors and histological signs of cell proliferation and tumor growth.

Adenoma↗
PubMed1980

Relationship of presence of progesterone receptors to prognosis in early breast cancer.

The presence of progesterone receptors was found to be associated with a favorable prognosis in 98 patients with primary breast cancer. The occurrence of metastases was 3.6 times less probable in patients with progesterone receptor-positive tumors than in patients with progesterone receptor-negative tumors. There was also an inverse relationship between the concentration of progesterone receptor and the frequency of metastases. However, there was no statistical correlation between frequency of local recurrences and progesterone receptor content of the tumor. In patients displaying clinical or histological criteria of gravity, the presence of progesterone receptors allowed us to define subgroups with good prognosis. Thus, in women with progesterone receptor-positive cancers, metastases had occurred at 18 months, in only 5% of the 39 Grade III cancers and in none of the 25 cases with invaded axillary nodes. Measurement of estradiol receptor (105 patients including the previous 98 patients) was found to be less effective for guiding the prognosis of early breast cancer. Combined evaluation of estradiol and progesterone receptors did not provide any more information than did the determination of progesterone receptor alone.

Adult↗
PubMed1977

Characterization and assay of progesterone receptor in human mammary carcinoma.

[3H]Pregn-4-ene-3,20-dione ([3H]progesterone)-receptor complexes from human mammary carcinoma were found to be stabilized in the presence of glycerol. The dissociation rate constant was lowered and the equilibrium dissociation constant was decreased (KD=3 nM in the absence of glycerol and 1.1 nM in the presence of 30% glycerol), whereas no clear-cut effect on the association rate was observed and no change occurred in the concentration of binding sites. Cortisol was found to compete with [3H]progesterone only at concentrations higher than 1 muM. This made it possible to distinguish [3H]progesterone binding to the receptor from binding to corticosteroid-binding globulin. Synthetic progestins [6-chloro-17-acetoxypregna-4,6-diene-3,20-dione (chlromadinone acetate), 17alpha-ethinyl, 17-hydroxyestr-4-en-3-one (norethisterone), and 17,21-dimethyl-19-norpregna-4,9-diene-3,20-dione (R5020)] were found to have a high affinity for the receptor, whereas 5alpha-pregnane-3,20-dione had an affinity about one-half that of progesterone itself 5beta-Pregnane-3,20-dione, 17alpha-hydroxypregn-4-ene-3,20-dione (estradiol), 11beta,21-dihydroxy-pregn-4-ene-3,20-dione (corticosterone), estra-1,3,5(10)-triene-3,17beta-diol, and 17beta-hydroxyandrost-4-en-3-one (testosterone) were weak inhibitors of [3H]progesterone binding. Sedimentation on glycerol gradients showed different patterns in different tumors; i.e., [3H]progesterone specific binding having the characteristics of receptor was found either in the 8 S region, in the 4.5 S region, or in both. Activated progesterone-receptor complex from human mammary carcinoma cytosol was shown to bind to human DNA. An assay of the receptor based on these binding properties is described. This assay measures the total concentration of cytosol receptor since it makes possible the exchange of endogenous hormone for excess added [3H]progesterone. Of 55 biopsies examined by this method, 35 (64%) had a concentration of progesterone receptor-binding sites higher than 10 fmoles/mg protein. There was a positive correlation between the amounts of estrogen and progesterone receptors.

20-alpha-Dihydroprogesterone↗
PubMedDate not supplied

Comparison of Cyfra 21-1 and SCC assays in head and neck tumours.

Patients with head and neck tumours (HNT) have a high risk of early locoregional relapse that is difficult to diagnose. This study evaluated the usefulness of the serum Cyfra 21-1 assay compared to squamous cell carcinoma antigen (SCC) assay for monitoring such patients. Three hundred and twelve HNT patients, including 204 newly diagnosed patients, were followed up for a median of 446 days with serial serum assays for SCC and Cyfra 21-1. Untreated patients showed SCC and Cyfra 21-1 serum levels correlated with each other: concentration was correlated to clinical stage, tumour size (as T1 + T2 vs. T3 + T4) and nodal status. Cyfra 21-1, but not SCC, was related to the presence of metastases and the primary tumour site, with a univariate prognostic value for disease-free survival (p = 0.015). Cox's regression analysis showed that only Cyfra 21-1 was associated with a risk of relapse (p = 0.027). The random coefficient growth curve model applied to serial SCC and Cyfra 21-1 measurements of 111 patients showed that only Cyfra 21-1 exhibited a significant difference between patients with and without relapses. We found Cyfra 21-1 to be more closely related to initial clinical data and disease evolution than SCC, and therefore propose the use of Cyfra 21-1 for monitoring head and neck cancers.

Adenocarcinoma↗
PubMedDate not supplied

Prognostic value of CA 15.3 kinetics for metastatic breast cancer.

Up to 80% of breast cancer patients developing metastases have high levels of CA 15.3. We studied the prognostic implications of CA 15.3 kinetics in 119 patients before and at first metastasis by univariate and multivariate statistics. At first metastasis, CA 15.3 was elevated in 82.4% of patients, with a lead time (median 162 days) in 42.0% of them. Kaplan-Meier analysis showed overall survival (median 1477 days) to be significantly related to estrogen receptor (ER) and progesterone receptor (PgR) status (p=0.0001) and tumor size (p=0.025). The interval between diagnosis and first abnormal CA 15.3 (p=0.0001), the CA 15.3 concentration (p=0.013), and the presence or absence of a lead time (p=0.001) also had prognostic value. ER and PgR status (p=0.0005 and p=0.0103, respectively), metastasis-free interval (p=0.0003), existence of a CA 15.3 lead time (p=0.0028), and days from diagnosis to first abnormal CA 15.3 (p=0.0055) entered in the Cox model. After first metastasis (median survival 573 days), ER and PgR status (p=0.0001 and p=0.0004, respectively), existence of a lead time for CA 15.3 (p=0.0138), and the concentration of first abnormal CA 15.3 (p=0.0145) had individual prognostic value. In the Cox model ER status (p=0.0001), nodal status (p=0.0191), existence of a lead time for CA 15.3 (p=0.0033), days from diagnosis to first abnormal CA 15.3 (p=0.0132), and concentration of first abnormal CA 15.3 (p=0.0320) were found to be independent prognostic variables. Compared to a matched historical control group that was not monitored by CA 15.3 assaying (n=140), the study group had a significantly longer survival after the first metastasis (p=0.0005). In conclusion, the kinetics of CA 15.3 before the first metastasis is of prognostic value. When associated with 18-fluorodeoxyglucose imaging, serial CA 15.3 assays may help to implement early treatment of metastases.

Adult↗