We have investigated the effect of estrogen on p53 cellular location and its influence on tumor c... more We have investigated the effect of estrogen on p53 cellular location and its influence on tumor cell susceptibility to tumor necrosis factor (TNF)-mediated cytotoxic action. For this purpose, we have used the TNF-sensitive human breast adenocarcinoma MCF-7 and its derivative, the TNF-resistant 1001 clone. Our data indicate that although estrogen receptor (ER)a is present in both cell lines, estrogen treatment (1 Â 10 À8 M) has an influence only on the MCF-7 cells and protects these cells from the TNF cytotoxicity. This protective effect is associated with translocation of p53 from the nucleus to the cytoplasm in p53 wild-type MCF-7 and not in p53-mutated 1001 cells. The translocation of p53 in MCF-7 cells results in a decrease in its transcriptional activity, as revealed by diminished p21 WAF1/CIP1 induction and an altered ratio of Bax and Bcl-2 proteins. The estrogen-induced effects are reversed by the selective estrogen inhibitor 182, 780 (1 Â 10 À6 M). Interestingly, transient transfection of MCF-7 cells with ERb but not ERa cDNA encoding plasmid results in retention of p53 in the nucleus, a subsequent potentiation of its transcriptional activity, and in an increased MCF-7 sensitivity to TNF. The estrogen effects on p53 location and transcriptional activity may involve the mdm2 protein since both events were reversed following MCF-7 transfection with plasmid encoding the ARF cDNA. These studies suggest that estrogen-induced MCF-7 cell survival in the presence of TNF requires a transcriptionally active p53 and, more importantly, indicate that introduction of ERb can attenuate the estrogen effects on the p53 protein location, its transcriptional activity and also results in a potentiation of cell sensitivity to TNF-mediated cell death.
Cette thèse de doctorat a été numérisée par l'Université libre de Bruxelles. L'auteur qui s'oppos... more Cette thèse de doctorat a été numérisée par l'Université libre de Bruxelles. L'auteur qui s'opposerait à sa mise en ligne dans DI-fusion est invité à prendre contact avec l'Université
In recent years, it has been repeatedly demonstrated that estrogen receptor (ER) assays are usefu... more In recent years, it has been repeatedly demonstrated that estrogen receptor (ER) assays are useful as a therapeutic guide in the treatment of advanced breast cancer. The validity of this tool in predicting the results of endocrine treatments has been confirmed in our laboratory [1, 2] as well as in many others (review article, ref. [3]). Moreover, we found that among several variables known to have a predictive value, receptor concentration was the one most significantly related to the therapeutic response; the presence or absence of ER was of lesser value [1,2].
Editorial on the Research Topic Underlying molecular interconnections of the estrogen receptor al... more Editorial on the Research Topic Underlying molecular interconnections of the estrogen receptor alpha and associated factors involved in breast cancer development: The way to new therapeutic approaches Estrogen receptors (ER)a and b contribute to the evolution of hormone-dependent breast cancers, an evolution that may be counteracted by antiestrogens or aromatase inhibitors which block estrogen synthesis. Implication of ERa in this therapy justifies its selection for this publication, although ERb may contribute through specific antagonist activity. ERa (as all steroid hormone receptors) belongs to the family of "nuclear receptors", which modulate the expression of genes working as transcription factors. The localization of a large majority of the active receptors within the cell nucleus justifies this classification terminology, even if a palmitoylated receptor form anchored at the plasma membrane operates by inducing transient signal transduction pathways. In fact, both receptor pools usually cooperate, the membrane receptor acting largely before the nuclear form to generate coherent and irreversible transcriptions to maintain homeostasis or induce evolution to satisfy extra-and intra-cellular requirements. In this context, a complementary G protein coupled-estrogen receptor structurally distinct from ERa localized within the plasma membrane-GPR30-should be mentioned, as it interacts with a "coregulator" recruitment hub of ERa (aa 295-311). The presence of GPR30 together with a truncated receptor form (ERa36) present in ERa-negative cells opens Frontiers in Endocrinology frontiersin.org 01
ChemInform Abstract Several diarylindoles (I) are synthesized by standard procedures described in... more ChemInform Abstract Several diarylindoles (I) are synthesized by standard procedures described in the literature and their estrogen receptor affinity is tested. (1H-NMR-data).
The synthesis of 4′, a titanocene derivative of the anticancer drug tamoxifen is presented togeth... more The synthesis of 4′, a titanocene derivative of the anticancer drug tamoxifen is presented together with its biochemical properties. Compound 4′ is prepared by a McMurry coupling followed by a ligand exchange. Compound 4′ reveals an unexpected proliferative effect on the hormone-dependent cell line MCF7. Surprisingly this effect is also observed with Cp2TiCl2 alone.
Synthesis of 7, a ferrocene derivative of the antiestrogenic drug hydroxytamoxifen bearing a basi... more Synthesis of 7, a ferrocene derivative of the antiestrogenic drug hydroxytamoxifen bearing a basic chain-O(CH 2) n N(CH 3) 2 with n= 4 is presented, together with both studies of its antiproliferative effect on the hormone-dependent MCF7 cell line (estrogen receptor positive cells) and of its genotoxicity. This molecule is easily prepared via a McMurry coupling reaction. The antiproliferative effect found for 7 at an incubation molarity of 1 mM was very close to that found for the usual reference molecule, namely OH-tamoxifen. In addition to its structural antiestrogenic effect, 7 showed cytotoxic activity probably due to the vectored ferrocene. This genotoxic component was confirmed by a 3D (damaged DNA detection) test, that permits identification and quantification of lesions induced on DNA. Some key interactions of 7 docked into the alpha-estrogen receptor binding site were also shown.
A series of ferrocene derivatives based upon the structure of the antiestrogenic drug tamoxifen o... more A series of ferrocene derivatives based upon the structure of the antiestrogenic drug tamoxifen or of its active metabolite hydroxytamoxifen has been prepared and named by analogy ferrocifens and hydroxyferrocifens. This series includes 1‐[4‐(O(CH2)nNMe2)phenyl]‐1‐phenyl‐2‐ferrocenyl‐but‐1‐ene and 1‐[4‐(O(CH2)nNMe2)phenyl]‐1‐(4‐hydroxyphenyl)‐2‐ferrocenyl‐but‐1‐ene, with n=2, 3, 5 and 8, and 1‐[4‐(O(CH2)2NMe2)phenyl]‐1‐(4‐hydroxyphenyl)‐2‐ferrocenylethene. Most of these molecules have been synthesised by McMurry cross‐coupling of the appropriate ketones, except for the ethene complexes, which were prepared by a four‐step reaction sequence starting from the ferrocenylacetic acid. All these compounds were obtained as mixtures of Z and E isomers. The isomers were separated in the cases of the ferrocenyl derivatives of tamoxifen and hydroxytamoxifen (n=2). No isomerisation of the Z and E isomers occurred in DMSO after one day, while a 50:50 mixture of the isomers was obtained within one hour in chloroform. The X‐ray structure of (E)‐1‐[4‐(O(CH2)2NMe2)phenyl]‐1‐(4‐hydroxyphenyl)‐2‐ferrocenyl‐but‐1‐ene has been determined. The relative binding affinity (RBA) values of the hydroxyferrocifens for the estrogen receptor alpha (ERα) was good to moderate, with values decreasing progressively with the length of the basic chain. The RBA values found for the estrogen receptor beta (ERβ) are equal to or slightly less than those found for the alpha form. The lipophilicity of the hydroxyferrocifens are superior to the values found for estradiol and increase with lengthening of the chain. The antiproliferative effects of the four hydroxyferrocifens with n=2, 3, 5 and 8 were studied on four breast cancer cell lines (MCF7, MDA‐MB231, RTx6 and TD5) possessing different levels of ERα. On MCF7 cells containing high levels of ERα, hydroxyferrocifens behave as antiestrogens. At a molarity of 1 μM the effect is close to that of hydroxytamoxifen (used for reference) when n=2 or 5, more marked when n=3, and weaker when n=8. Ferrocene alone has no effect. For the MDA‐MB231 cells, classed as a hormone‐independent breast cancer cell line, on the other hand, the hydroxyferrocifens show remarkable antiproliferative behaviour while the hydroxytamoxifen is completely inactive. Hydroxyferrocifens therefore show the unique property of being active both on hormone‐dependent and on hormone‐independent breast cancer cell lines. The molecular modelling study provides some clues for understanding of the antagonist effect of these molecules, while an additional cytotoxic effect due to the vectorised ferrocenyl unit is revealed in some occasions.
The interest of estrogen receptor assays has been pointed out by numerous authors [1], especially... more The interest of estrogen receptor assays has been pointed out by numerous authors [1], especially with reference to the determination of potential responders to endocrine therapy among generalized breast cancer patients. The relationship between the estrogen receptor level in breast primaries and other prognostic factors remains a matter of controversy and is the subject of the following article, which is based on a series of 490 previously unreported cases.
Specific quantitative techniques have been used to measure the cytoplasmic estradiol-binding prot... more Specific quantitative techniques have been used to measure the cytoplasmic estradiol-binding protein (EBP) in human mammary carcinoma tissue specimens. Sucrose gradient centrifugation reveals EBP to sediment at 8S and 4S. Variable quantities of nonspecific estradiol binding occurs in the 4S region of the sucrose gradient necessitating controls to insure specificity of the estradiol protein interaction. Using dextran-coated charcoal to separate bound from free estradiol Scatchard analysis finds the dissociation constant of the estradiol EBP interaction to be 2.6 X 10-1O M, indicative of the very high affinity of the ligand for the EBP. Quantitation of EBP sites in 64 primary and metastatic human breast tumors demonstrates a continuous spectrum of values from 0 to 612 fmol per mg of cytoplasmic protein. Specific 8S binding in the sucrose gradient centrifugation was not detected in specimens containing less than 9.0 fmol EBP per mg cytoplasmic protein. Since data from animal breast tumors and preliminary evidence from human breast tumors indicates an excellent correlation between the presence of abundant tumor EBP and endocrine-induced breast cancer regressions, precise quantitation of EBP in all human primary tumors may prove to be an excellent prognosticator of endocrine therapy in metastatic breast cancer.
Abstract Samples from 77 primary and 65 metastatic human breast cancers were assayed for specific... more Abstract Samples from 77 primary and 65 metastatic human breast cancers were assayed for specific cytoplasmic estrogen receptors. Cytosol preparations were incubated with increasing amounts of 3 H-estradiol- 17 β. The unbound radioactivity was removed by charcoal-coated dextran. Saturable high affinity binding sites were detected in 56% of the primary and 37% of the metastatic tumors. The binding constants of these receptor sites for estradiol were quite variable; most ranged from 1·0 to 20 × 10 −10 M, but some were larger (up to 108 × 10 −10 M). The concentrations of binding sites were distributed within a continuous range from 5 to 1330 femtomoles per mg protein. This wide range was not ascribable only to variations in amounts of contaminating serum proteins. Receptors were detected in only 8% of cytosol preparations containing less than 2 mg protein per ml; in contrast they were detected in 53% of cases with higher protein concentration. This indicates that at low protein concentration, false negative results are likely to occur. Detectable amounts of receptors were not found in sera or samples from normal mammary gland, nipple, areola, skin and non-invaded lymph nodes. The reliability of a simplified procedure based on isotopic dilution of the labelled estradiol, to be used with very small tumor tissue samples, was studied. It compared quite well with the other one except in case of very low concentrations of receptor. No relationship was found between the occurrence of receptor and the age of the patient or the histological type of the tumor. There was also no relationship between the occurrence of receptors in the primary tumor and presence or absence of metastatic axillary lymph nodes. However, when present, the latter had the same characteristics with respect to the receptor as the corresponding primary, with only one exception. In cases of metastatic tumors, no correlation was observed with the free interval.
The discovery of a panel of peptides produced by normal and cancerous cells and capable of stimul... more The discovery of a panel of peptides produced by normal and cancerous cells and capable of stimulating cell growth in an autocrine and paracrine fashion has been witnessed in recent years. This article focusses on the local growth factors thought to play a role in the biology of breast cancer and reviews which growth factors' receptors have been associated with prognosis of primary breast cancer. The potential of those growth factors for the development of new anticancer treatment strategies is also briefly discussed.
Hétérogénéité structurale du récepteur d'oestrogènes dans le cancer mammaire humain (Unpublished ... more Hétérogénéité structurale du récepteur d'oestrogènes dans le cancer mammaire humain (Unpublished doctoral dissertation).
Polychemotherapy and hormonal therapy are currently the major therapeutic modalities in advanced ... more Polychemotherapy and hormonal therapy are currently the major therapeutic modalities in advanced breast cancer. The former is the most effective (≥ 50 percent response rate) but the second is less toxic, with a response rate of about 30%. The recent development of estrogen receptor determination in breast cancer tissue samples has improved the clinician’s ability to use these modalities either separately or together in an optimum manner.
I. Receptor Assays.- Classical Methods.- Sampling and Storage of Breast Cancer Tissue for Steroid... more I. Receptor Assays.- Classical Methods.- Sampling and Storage of Breast Cancer Tissue for Steroid Receptor Assays.- Routine Assays for Steroid Hormone Receptors.- Mathematical Analysis of Data from Receptor Assays.- New Methods.- Estrogen and Progestin Receptor Analysis in Human Breast Cancer by Isoelectric Focusing in Slabs of Polyacrylamide Gel.- Estrogen Receptor Analysis on Fine Needle Aspirates from Human Breast Carcinoma.- Estrogen and Progestin Receptors on Drill Biopsy Samples of Human Mammary Tumors.- The Value of Determination of Nuclear Oestrogen Receptors in Breast Cancer Biopsies.- Histochemical Methods.- Immunocytochemical Demonstration of Steroid Receptors.- Use of Fluorescent Sex-Steroid Conjugates for the Histochemical Detection of Breast Cancer Cell Receptors: A Critique.- Microscopic Visualization of Steroid Receptor Sites: A Mirage?.- I: A Critical Summary 86 R. J. B. King.- II. Quality Control.- Quality Control of Estrogen and Progesterone Receptor Analyses in Denmark.- Results of External Quality Control Trials Performed by the German Cooperative Group for Receptor Assay Standardization.- British Interlaboratory Quality Assessment of Steroid Receptor Assays.- Quality Control Program for Estradiol Receptor Determination: The Italian Experience.- Quality Control of Steroid Receptor Assays in the Netherlands.- Quality Control of Clinical Steroid Receptor Assays in Sweden.- Interlaboratory Variability in the Determination of Estrogen Receptor and Progesterone Receptor Content in Human Breast Tumors.- Standardization of Steroid Receptor Analysis in Breast Cancer Biopsies: EORTC Receptor Group.- II: A Critical Summary 136 G. Leclercq.- III. Biology of the Primary Tumor.- Estrogen Receptors and Distribution of Prognostic Factors in Primary Breast Cancer.- Influence of Intratumoral Estradiol Biosynthesis on Estrogen Receptors.- Influence of Endogenous Hormone Levels on Tumor Estradiol and Progesterone Receptors.- Inflammatory Tumors of the Human Breast: Determination of Estrogen and Progesterone Receptors.- Relationship Between Estrogen Receptors and Cellular Proliferation.- Relationship of Stromal Elastosis to Steroid Receptors in Human Breast Carcinoma.- III: A Critical Summary 176 G. Contesso, J. C. Delarue, F. May-Levin, H. Sancho-Gamier, H. Mouriesse.- IV. The Course of Disease.- Estrogen Receptor Variations in Neoplastic Tissue During the Course of Disease in Patients with Recurrent Breast Cancer.- The Prognostic Value of Progesterone Receptors in Primary Breast Cancer.- Estrogen and Progesterone Receptors as Prognostic Factors in Early Breast Cancer.- IV: A Critical Summary 199 L. Santi.- V. Treatments.- Adjuvant Treatment.- Relationship Between Estrogen Receptors and CMF Adjuvant Chemotherapy.- New Adjuvant Trials for Resectable Breast Cancer at the Istituto Nazionale Tumori of Milan.- Effect of Adjuvant Therapy in Primary Breast Cancer in Relation to the Estrogen Receptor Level.- V: A Critical Summary.- Palliative Treatment.- Endocrine Surgery in Breast Cancer.- Treatment of Advanced Breast Cancer with Tamoxifen.- Therapeutic Activity of Medroxyprogesterone Acetate in Metastatic Breast Cancer: A Correlation Between Estrogen Receptors and Various Dosages.- Estrogen Receptor Status and the Clinical Response to a Combination of Aminoglutethimide and Cortisol in Advanced Breast Cancer.- Steroid Receptors in Megestrol Acetate Therapy.- Protocols Based on Steroid Receptors: Great Britain.- Currently Active Protocols in the EORTC Breast Cancer Cooperative Group.- The Place of Hormone Receptors in the Elaboration of a Therapeutic Strategy Against Breast Cancer.- V: A Critical Summary.- VI. Prospects for Future Tests of Hormone Dependence.- Peroxidase Activity as a Marker for Estrogen Action in Rat Uteri and Human Mammary Carcinomas.- Estrogen-Induced Proteins in Human Breast Cancer Cells.- Stimulation by 17?-Estradiol of a Secreted Glycoprotein in MCF-7 Cells and Human Breast Cancer.- Estrogen Action on the Synthesis and Secretion of a Broad Spectrum of Proteins in Mammary Tumor Cells.- VII. Laboratories Performing Receptor Assays.- Austria.- Belgium (and Luxembourg).- Denmark.- Federal Republic of Germany.- France.- Great Britain.- Ireland.- Italy.- The Netherlands.- Spain.- Sweden (and Norway).- Switzerland.
A novel series of estrone derivatives having a free 3-phenolic group with the 2-or 4-position sub... more A novel series of estrone derivatives having a free 3-phenolic group with the 2-or 4-position substituted with a thiourea function was synthesized. None of the products showed significant binding to the estrogen receptor, and the cytotoxic activity on MCF-7 cells for VII and X was weak. Keyphrases 0 Estrone 2-and 4-thiourea derivatives-free phenolic group, synthesis, binding to the estrogen receptor, cytotoxic activity Steroidal thiourea derivatives-2-or 4-position of cstrone, synthesis binding to the estrogen receptor, cytotoxic activity
Human mammary carcinoma cell lines (MCF‐7) were analysed for their hormone sensitivity before and... more Human mammary carcinoma cell lines (MCF‐7) were analysed for their hormone sensitivity before and after transfection with a v‐Ha‐ras oncogene or with a neomycin‐resistance gene followed by selection in vitro or in vivo. Our aim was to test how the expression of the ras oncogene would influence the estradiol sensitivity of MCF‐7 cells. In culture, MCF‐7 cells expressing the viral p21 oncogene product, as compared to parental MCF‐7 cells and their control derivatives, showed lower levels of a 67‐kDa estrogen receptor. Progesterone receptors, however, remained sensitive to up‐regulation by estrogens. The oncogene‐expressing cells were less sensitive than all controls to stimulation of proliferation by 10‐8M estradiol or to inhibition of proliferation by 2‐CH3‐4‐OH tamoxifen, and this was not dependent upon the type of culture medium used. After s. c. or i. p. injection into female athymic nude mice, ovariectomized or left intact, the growth of MCF‐7 cells expressing the ras oncogene pr...
We have investigated the effect of estrogen on p53 cellular location and its influence on tumor c... more We have investigated the effect of estrogen on p53 cellular location and its influence on tumor cell susceptibility to tumor necrosis factor (TNF)-mediated cytotoxic action. For this purpose, we have used the TNF-sensitive human breast adenocarcinoma MCF-7 and its derivative, the TNF-resistant 1001 clone. Our data indicate that although estrogen receptor (ER)a is present in both cell lines, estrogen treatment (1 Â 10 À8 M) has an influence only on the MCF-7 cells and protects these cells from the TNF cytotoxicity. This protective effect is associated with translocation of p53 from the nucleus to the cytoplasm in p53 wild-type MCF-7 and not in p53-mutated 1001 cells. The translocation of p53 in MCF-7 cells results in a decrease in its transcriptional activity, as revealed by diminished p21 WAF1/CIP1 induction and an altered ratio of Bax and Bcl-2 proteins. The estrogen-induced effects are reversed by the selective estrogen inhibitor 182, 780 (1 Â 10 À6 M). Interestingly, transient transfection of MCF-7 cells with ERb but not ERa cDNA encoding plasmid results in retention of p53 in the nucleus, a subsequent potentiation of its transcriptional activity, and in an increased MCF-7 sensitivity to TNF. The estrogen effects on p53 location and transcriptional activity may involve the mdm2 protein since both events were reversed following MCF-7 transfection with plasmid encoding the ARF cDNA. These studies suggest that estrogen-induced MCF-7 cell survival in the presence of TNF requires a transcriptionally active p53 and, more importantly, indicate that introduction of ERb can attenuate the estrogen effects on the p53 protein location, its transcriptional activity and also results in a potentiation of cell sensitivity to TNF-mediated cell death.
Cette thèse de doctorat a été numérisée par l'Université libre de Bruxelles. L'auteur qui s'oppos... more Cette thèse de doctorat a été numérisée par l'Université libre de Bruxelles. L'auteur qui s'opposerait à sa mise en ligne dans DI-fusion est invité à prendre contact avec l'Université
In recent years, it has been repeatedly demonstrated that estrogen receptor (ER) assays are usefu... more In recent years, it has been repeatedly demonstrated that estrogen receptor (ER) assays are useful as a therapeutic guide in the treatment of advanced breast cancer. The validity of this tool in predicting the results of endocrine treatments has been confirmed in our laboratory [1, 2] as well as in many others (review article, ref. [3]). Moreover, we found that among several variables known to have a predictive value, receptor concentration was the one most significantly related to the therapeutic response; the presence or absence of ER was of lesser value [1,2].
Editorial on the Research Topic Underlying molecular interconnections of the estrogen receptor al... more Editorial on the Research Topic Underlying molecular interconnections of the estrogen receptor alpha and associated factors involved in breast cancer development: The way to new therapeutic approaches Estrogen receptors (ER)a and b contribute to the evolution of hormone-dependent breast cancers, an evolution that may be counteracted by antiestrogens or aromatase inhibitors which block estrogen synthesis. Implication of ERa in this therapy justifies its selection for this publication, although ERb may contribute through specific antagonist activity. ERa (as all steroid hormone receptors) belongs to the family of "nuclear receptors", which modulate the expression of genes working as transcription factors. The localization of a large majority of the active receptors within the cell nucleus justifies this classification terminology, even if a palmitoylated receptor form anchored at the plasma membrane operates by inducing transient signal transduction pathways. In fact, both receptor pools usually cooperate, the membrane receptor acting largely before the nuclear form to generate coherent and irreversible transcriptions to maintain homeostasis or induce evolution to satisfy extra-and intra-cellular requirements. In this context, a complementary G protein coupled-estrogen receptor structurally distinct from ERa localized within the plasma membrane-GPR30-should be mentioned, as it interacts with a "coregulator" recruitment hub of ERa (aa 295-311). The presence of GPR30 together with a truncated receptor form (ERa36) present in ERa-negative cells opens Frontiers in Endocrinology frontiersin.org 01
ChemInform Abstract Several diarylindoles (I) are synthesized by standard procedures described in... more ChemInform Abstract Several diarylindoles (I) are synthesized by standard procedures described in the literature and their estrogen receptor affinity is tested. (1H-NMR-data).
The synthesis of 4′, a titanocene derivative of the anticancer drug tamoxifen is presented togeth... more The synthesis of 4′, a titanocene derivative of the anticancer drug tamoxifen is presented together with its biochemical properties. Compound 4′ is prepared by a McMurry coupling followed by a ligand exchange. Compound 4′ reveals an unexpected proliferative effect on the hormone-dependent cell line MCF7. Surprisingly this effect is also observed with Cp2TiCl2 alone.
Synthesis of 7, a ferrocene derivative of the antiestrogenic drug hydroxytamoxifen bearing a basi... more Synthesis of 7, a ferrocene derivative of the antiestrogenic drug hydroxytamoxifen bearing a basic chain-O(CH 2) n N(CH 3) 2 with n= 4 is presented, together with both studies of its antiproliferative effect on the hormone-dependent MCF7 cell line (estrogen receptor positive cells) and of its genotoxicity. This molecule is easily prepared via a McMurry coupling reaction. The antiproliferative effect found for 7 at an incubation molarity of 1 mM was very close to that found for the usual reference molecule, namely OH-tamoxifen. In addition to its structural antiestrogenic effect, 7 showed cytotoxic activity probably due to the vectored ferrocene. This genotoxic component was confirmed by a 3D (damaged DNA detection) test, that permits identification and quantification of lesions induced on DNA. Some key interactions of 7 docked into the alpha-estrogen receptor binding site were also shown.
A series of ferrocene derivatives based upon the structure of the antiestrogenic drug tamoxifen o... more A series of ferrocene derivatives based upon the structure of the antiestrogenic drug tamoxifen or of its active metabolite hydroxytamoxifen has been prepared and named by analogy ferrocifens and hydroxyferrocifens. This series includes 1‐[4‐(O(CH2)nNMe2)phenyl]‐1‐phenyl‐2‐ferrocenyl‐but‐1‐ene and 1‐[4‐(O(CH2)nNMe2)phenyl]‐1‐(4‐hydroxyphenyl)‐2‐ferrocenyl‐but‐1‐ene, with n=2, 3, 5 and 8, and 1‐[4‐(O(CH2)2NMe2)phenyl]‐1‐(4‐hydroxyphenyl)‐2‐ferrocenylethene. Most of these molecules have been synthesised by McMurry cross‐coupling of the appropriate ketones, except for the ethene complexes, which were prepared by a four‐step reaction sequence starting from the ferrocenylacetic acid. All these compounds were obtained as mixtures of Z and E isomers. The isomers were separated in the cases of the ferrocenyl derivatives of tamoxifen and hydroxytamoxifen (n=2). No isomerisation of the Z and E isomers occurred in DMSO after one day, while a 50:50 mixture of the isomers was obtained within one hour in chloroform. The X‐ray structure of (E)‐1‐[4‐(O(CH2)2NMe2)phenyl]‐1‐(4‐hydroxyphenyl)‐2‐ferrocenyl‐but‐1‐ene has been determined. The relative binding affinity (RBA) values of the hydroxyferrocifens for the estrogen receptor alpha (ERα) was good to moderate, with values decreasing progressively with the length of the basic chain. The RBA values found for the estrogen receptor beta (ERβ) are equal to or slightly less than those found for the alpha form. The lipophilicity of the hydroxyferrocifens are superior to the values found for estradiol and increase with lengthening of the chain. The antiproliferative effects of the four hydroxyferrocifens with n=2, 3, 5 and 8 were studied on four breast cancer cell lines (MCF7, MDA‐MB231, RTx6 and TD5) possessing different levels of ERα. On MCF7 cells containing high levels of ERα, hydroxyferrocifens behave as antiestrogens. At a molarity of 1 μM the effect is close to that of hydroxytamoxifen (used for reference) when n=2 or 5, more marked when n=3, and weaker when n=8. Ferrocene alone has no effect. For the MDA‐MB231 cells, classed as a hormone‐independent breast cancer cell line, on the other hand, the hydroxyferrocifens show remarkable antiproliferative behaviour while the hydroxytamoxifen is completely inactive. Hydroxyferrocifens therefore show the unique property of being active both on hormone‐dependent and on hormone‐independent breast cancer cell lines. The molecular modelling study provides some clues for understanding of the antagonist effect of these molecules, while an additional cytotoxic effect due to the vectorised ferrocenyl unit is revealed in some occasions.
The interest of estrogen receptor assays has been pointed out by numerous authors [1], especially... more The interest of estrogen receptor assays has been pointed out by numerous authors [1], especially with reference to the determination of potential responders to endocrine therapy among generalized breast cancer patients. The relationship between the estrogen receptor level in breast primaries and other prognostic factors remains a matter of controversy and is the subject of the following article, which is based on a series of 490 previously unreported cases.
Specific quantitative techniques have been used to measure the cytoplasmic estradiol-binding prot... more Specific quantitative techniques have been used to measure the cytoplasmic estradiol-binding protein (EBP) in human mammary carcinoma tissue specimens. Sucrose gradient centrifugation reveals EBP to sediment at 8S and 4S. Variable quantities of nonspecific estradiol binding occurs in the 4S region of the sucrose gradient necessitating controls to insure specificity of the estradiol protein interaction. Using dextran-coated charcoal to separate bound from free estradiol Scatchard analysis finds the dissociation constant of the estradiol EBP interaction to be 2.6 X 10-1O M, indicative of the very high affinity of the ligand for the EBP. Quantitation of EBP sites in 64 primary and metastatic human breast tumors demonstrates a continuous spectrum of values from 0 to 612 fmol per mg of cytoplasmic protein. Specific 8S binding in the sucrose gradient centrifugation was not detected in specimens containing less than 9.0 fmol EBP per mg cytoplasmic protein. Since data from animal breast tumors and preliminary evidence from human breast tumors indicates an excellent correlation between the presence of abundant tumor EBP and endocrine-induced breast cancer regressions, precise quantitation of EBP in all human primary tumors may prove to be an excellent prognosticator of endocrine therapy in metastatic breast cancer.
Abstract Samples from 77 primary and 65 metastatic human breast cancers were assayed for specific... more Abstract Samples from 77 primary and 65 metastatic human breast cancers were assayed for specific cytoplasmic estrogen receptors. Cytosol preparations were incubated with increasing amounts of 3 H-estradiol- 17 β. The unbound radioactivity was removed by charcoal-coated dextran. Saturable high affinity binding sites were detected in 56% of the primary and 37% of the metastatic tumors. The binding constants of these receptor sites for estradiol were quite variable; most ranged from 1·0 to 20 × 10 −10 M, but some were larger (up to 108 × 10 −10 M). The concentrations of binding sites were distributed within a continuous range from 5 to 1330 femtomoles per mg protein. This wide range was not ascribable only to variations in amounts of contaminating serum proteins. Receptors were detected in only 8% of cytosol preparations containing less than 2 mg protein per ml; in contrast they were detected in 53% of cases with higher protein concentration. This indicates that at low protein concentration, false negative results are likely to occur. Detectable amounts of receptors were not found in sera or samples from normal mammary gland, nipple, areola, skin and non-invaded lymph nodes. The reliability of a simplified procedure based on isotopic dilution of the labelled estradiol, to be used with very small tumor tissue samples, was studied. It compared quite well with the other one except in case of very low concentrations of receptor. No relationship was found between the occurrence of receptor and the age of the patient or the histological type of the tumor. There was also no relationship between the occurrence of receptors in the primary tumor and presence or absence of metastatic axillary lymph nodes. However, when present, the latter had the same characteristics with respect to the receptor as the corresponding primary, with only one exception. In cases of metastatic tumors, no correlation was observed with the free interval.
The discovery of a panel of peptides produced by normal and cancerous cells and capable of stimul... more The discovery of a panel of peptides produced by normal and cancerous cells and capable of stimulating cell growth in an autocrine and paracrine fashion has been witnessed in recent years. This article focusses on the local growth factors thought to play a role in the biology of breast cancer and reviews which growth factors' receptors have been associated with prognosis of primary breast cancer. The potential of those growth factors for the development of new anticancer treatment strategies is also briefly discussed.
Hétérogénéité structurale du récepteur d'oestrogènes dans le cancer mammaire humain (Unpublished ... more Hétérogénéité structurale du récepteur d'oestrogènes dans le cancer mammaire humain (Unpublished doctoral dissertation).
Polychemotherapy and hormonal therapy are currently the major therapeutic modalities in advanced ... more Polychemotherapy and hormonal therapy are currently the major therapeutic modalities in advanced breast cancer. The former is the most effective (≥ 50 percent response rate) but the second is less toxic, with a response rate of about 30%. The recent development of estrogen receptor determination in breast cancer tissue samples has improved the clinician’s ability to use these modalities either separately or together in an optimum manner.
I. Receptor Assays.- Classical Methods.- Sampling and Storage of Breast Cancer Tissue for Steroid... more I. Receptor Assays.- Classical Methods.- Sampling and Storage of Breast Cancer Tissue for Steroid Receptor Assays.- Routine Assays for Steroid Hormone Receptors.- Mathematical Analysis of Data from Receptor Assays.- New Methods.- Estrogen and Progestin Receptor Analysis in Human Breast Cancer by Isoelectric Focusing in Slabs of Polyacrylamide Gel.- Estrogen Receptor Analysis on Fine Needle Aspirates from Human Breast Carcinoma.- Estrogen and Progestin Receptors on Drill Biopsy Samples of Human Mammary Tumors.- The Value of Determination of Nuclear Oestrogen Receptors in Breast Cancer Biopsies.- Histochemical Methods.- Immunocytochemical Demonstration of Steroid Receptors.- Use of Fluorescent Sex-Steroid Conjugates for the Histochemical Detection of Breast Cancer Cell Receptors: A Critique.- Microscopic Visualization of Steroid Receptor Sites: A Mirage?.- I: A Critical Summary 86 R. J. B. King.- II. Quality Control.- Quality Control of Estrogen and Progesterone Receptor Analyses in Denmark.- Results of External Quality Control Trials Performed by the German Cooperative Group for Receptor Assay Standardization.- British Interlaboratory Quality Assessment of Steroid Receptor Assays.- Quality Control Program for Estradiol Receptor Determination: The Italian Experience.- Quality Control of Steroid Receptor Assays in the Netherlands.- Quality Control of Clinical Steroid Receptor Assays in Sweden.- Interlaboratory Variability in the Determination of Estrogen Receptor and Progesterone Receptor Content in Human Breast Tumors.- Standardization of Steroid Receptor Analysis in Breast Cancer Biopsies: EORTC Receptor Group.- II: A Critical Summary 136 G. Leclercq.- III. Biology of the Primary Tumor.- Estrogen Receptors and Distribution of Prognostic Factors in Primary Breast Cancer.- Influence of Intratumoral Estradiol Biosynthesis on Estrogen Receptors.- Influence of Endogenous Hormone Levels on Tumor Estradiol and Progesterone Receptors.- Inflammatory Tumors of the Human Breast: Determination of Estrogen and Progesterone Receptors.- Relationship Between Estrogen Receptors and Cellular Proliferation.- Relationship of Stromal Elastosis to Steroid Receptors in Human Breast Carcinoma.- III: A Critical Summary 176 G. Contesso, J. C. Delarue, F. May-Levin, H. Sancho-Gamier, H. Mouriesse.- IV. The Course of Disease.- Estrogen Receptor Variations in Neoplastic Tissue During the Course of Disease in Patients with Recurrent Breast Cancer.- The Prognostic Value of Progesterone Receptors in Primary Breast Cancer.- Estrogen and Progesterone Receptors as Prognostic Factors in Early Breast Cancer.- IV: A Critical Summary 199 L. Santi.- V. Treatments.- Adjuvant Treatment.- Relationship Between Estrogen Receptors and CMF Adjuvant Chemotherapy.- New Adjuvant Trials for Resectable Breast Cancer at the Istituto Nazionale Tumori of Milan.- Effect of Adjuvant Therapy in Primary Breast Cancer in Relation to the Estrogen Receptor Level.- V: A Critical Summary.- Palliative Treatment.- Endocrine Surgery in Breast Cancer.- Treatment of Advanced Breast Cancer with Tamoxifen.- Therapeutic Activity of Medroxyprogesterone Acetate in Metastatic Breast Cancer: A Correlation Between Estrogen Receptors and Various Dosages.- Estrogen Receptor Status and the Clinical Response to a Combination of Aminoglutethimide and Cortisol in Advanced Breast Cancer.- Steroid Receptors in Megestrol Acetate Therapy.- Protocols Based on Steroid Receptors: Great Britain.- Currently Active Protocols in the EORTC Breast Cancer Cooperative Group.- The Place of Hormone Receptors in the Elaboration of a Therapeutic Strategy Against Breast Cancer.- V: A Critical Summary.- VI. Prospects for Future Tests of Hormone Dependence.- Peroxidase Activity as a Marker for Estrogen Action in Rat Uteri and Human Mammary Carcinomas.- Estrogen-Induced Proteins in Human Breast Cancer Cells.- Stimulation by 17?-Estradiol of a Secreted Glycoprotein in MCF-7 Cells and Human Breast Cancer.- Estrogen Action on the Synthesis and Secretion of a Broad Spectrum of Proteins in Mammary Tumor Cells.- VII. Laboratories Performing Receptor Assays.- Austria.- Belgium (and Luxembourg).- Denmark.- Federal Republic of Germany.- France.- Great Britain.- Ireland.- Italy.- The Netherlands.- Spain.- Sweden (and Norway).- Switzerland.
A novel series of estrone derivatives having a free 3-phenolic group with the 2-or 4-position sub... more A novel series of estrone derivatives having a free 3-phenolic group with the 2-or 4-position substituted with a thiourea function was synthesized. None of the products showed significant binding to the estrogen receptor, and the cytotoxic activity on MCF-7 cells for VII and X was weak. Keyphrases 0 Estrone 2-and 4-thiourea derivatives-free phenolic group, synthesis, binding to the estrogen receptor, cytotoxic activity Steroidal thiourea derivatives-2-or 4-position of cstrone, synthesis binding to the estrogen receptor, cytotoxic activity
Human mammary carcinoma cell lines (MCF‐7) were analysed for their hormone sensitivity before and... more Human mammary carcinoma cell lines (MCF‐7) were analysed for their hormone sensitivity before and after transfection with a v‐Ha‐ras oncogene or with a neomycin‐resistance gene followed by selection in vitro or in vivo. Our aim was to test how the expression of the ras oncogene would influence the estradiol sensitivity of MCF‐7 cells. In culture, MCF‐7 cells expressing the viral p21 oncogene product, as compared to parental MCF‐7 cells and their control derivatives, showed lower levels of a 67‐kDa estrogen receptor. Progesterone receptors, however, remained sensitive to up‐regulation by estrogens. The oncogene‐expressing cells were less sensitive than all controls to stimulation of proliferation by 10‐8M estradiol or to inhibition of proliferation by 2‐CH3‐4‐OH tamoxifen, and this was not dependent upon the type of culture medium used. After s. c. or i. p. injection into female athymic nude mice, ovariectomized or left intact, the growth of MCF‐7 cells expressing the ras oncogene pr...
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