afimoxifene and Ovarian-Neoplasms

Anti-tumor efficacy of Gatipotuzumab, a therapeutic antibody targeting Tumor-Associated Mucin-1 (TA-MUC1), in relapsed ovarian cancer (OC) appeared to be rather heterogeneous. Whether adding a second anti-neoplastic drug may augment response towards Gatipotuzumab, has not been elucidated so far. Since it is known that anti-MUC1 antibodies may alter estrogen receptor activity in breast cancer, this potential interplay was investigated in OC. The correlation between TA-MUC1, estrogen receptors (ERs) and another 12 protein markers as well as their correlation with clinico-pathological parameters in 138 ovarian cancer cases was studied. Finally, Gatipotuzumab and 4-Hydroxy-TTamoxifen (4-OHT) as well as the combination of both was tested for its impact on cell viability in COV318, OV-90, OVCAR-3, and SKOV-3 cells. A strong positive correlation between TA-MUC1 and ERs was detected in OC tissue. Those cases missing ERs but staining positive for TA-MUC1 had significantly reduced overall survival. The combination of 4-OHT and Gatipotuzumab significantly reduced cell viability and was more effective than treatment with Gatipotuzumab alone. Co-stimulation with Gatipotuzumab enhanced the efficacy of 4-OHT in OVCAR-3 and SKOV-3. The data suggest an interplay of TA-MUC1 and ERs in OC. Whether the combination of Gatipotuzumab and TTamoxifen may enhance efficacy of either of the two drugs

Topics: Antibodies, Monoclonal, Humanized; Antineoplastic Combined Chemotherapy Protocols; Cell Line, Tumor; Cell Proliferation; Cell Survival; Epitopes; Female; Humans; Mucin-1; Ovarian Neoplasms; Receptors, Estrogen; Tamoxifen

The fallopian tube epithelium is one of the potential sources of high-grade serous ovarian cancer (HGSC). The use of estrogen only hormone replacement therapy increases ovarian cancer (OVCA) risk. Despite estrogen's influence in OVCA, selective estrogen receptor modulators (SERMs) typically demonstrate only a 20 % response rate. This low response could be due to a variety of factors including the loss of estrogen receptor signaling or the role of estrogen in different potential cell types of origin. The response of fallopian tube epithelium to SERMs is not known, and would be useful when determining therapeutic options for tumors arising from this cell type, such as HGSC.. Using normal murine derived oviductal epithelial cells (mouse equivalent to the fallopian tube) estrogen receptor expression was confirmed and interaction with its ligand, estradiol, triggered mRNA and protein induction of progesterone receptor (PR). The SERMs 4-hydroxytamoxifen, raloxifene and desmethylarzoxifene, functioned as estrogen receptor antagonists in oviductal cells. Cellular proliferation and migration assays suggested that estradiol does not significantly impact cellular migration and increased proliferation. Further, using RNAseq, the oviduct specific transcriptional genes targets of ER when stimulated by estradiol and 4-hydroxytamoxifen signaling were determined and validated. The RNA-seq revealed enrichment in proliferation, anti-apoptosis, calcium signaling and steroid signaling processes. Finally, the ER and PR receptor status of a panel of HGSC cell lines was investigated including Kuramochi, OVSAHO, OVKATE, OVCAR3, and OVCAR4. OVSAHO demonstrated receptor expression and response, which highlights the need for additional models of ovarian cancer that are estrogen responsive.. Overall, the fallopian tube has specific gene targets of estrogen receptor and demonstrates a tissue specific response to SERMs consistent with antagonistic action.

Topics: Animals; Antineoplastic Agents, Hormonal; Carcinoma in Situ; Cell Line, Tumor; Drug Resistance, Neoplasm; Estradiol; Estrogen Antagonists; Estrogens; Fallopian Tubes; Female; Gene Expression Regulation, Neoplastic; Genome; Humans; Mice; Neoplasms, Cystic, Mucinous, and Serous; Ovarian Neoplasms; Piperidines; Raloxifene Hydrochloride; Receptors, Estrogen; Tamoxifen; Thiophenes; Transcriptome

Follicle stimulating hormone receptor (FSHR) and luteinizing hormone receptor (LHCGR) were demonstrated to impact upon survival of patients suffering from epithelial ovarian cancer (EOC). Though structure wise the G-protein coupled estrogen receptor (GPER/GPR30) is related to FSHR/LHCGR, its prognostic impact in EOC remains controversial. We recently found that FSHR negative patients represent a specific EOC subgroup that may behave differently in respect to both treatment response and prognosis. Hence, the current study aimed to analyze how GPER may interact with the FSHR/LHCGR system in EOC and whether the prognostic significance of GPER in EOC cases (n=151) may be dependent on the FSHR/LHCGR immunophenotype of the tumor. Ovarian cancer cell lines were used to study how FSH and LH regulate GPER and whether GPER activation differentially affects in vitro cell proliferation in presence/absence of activated FSHR/LHCGR. In EOC tissue, GPER correlated with FSHR/LHCGR and was related to prolonged overall survival only in FSHR/LHCGR negative patients. Although GPER was found to be specifically induced by LH/FSH, GPER agonists (4-Hydroxy-Tamoxifen, G1) reduced EOC cell proliferation only in case of LH/FSH unstimulated pathways. To the same direction, only patients characterized as LHCGR/FSHR negative seem to gain from GPER in terms of survival. Our combined tissue and in vitro results support thus the hypothesis that GPER activation could be of therapeutic benefit in LHCGR/FSHR negative EOC patients. Further studies are needed to evaluate the impact of GPER activation on a clinical scheme.

Topics: Antineoplastic Agents; Biomarkers, Tumor; Carcinoma, Ovarian Epithelial; Cell Line, Tumor; Female; Gene Expression Regulation, Neoplastic; Humans; Middle Aged; Neoplasm Staging; Neoplasms, Glandular and Epithelial; Ovarian Neoplasms; Prognosis; Receptor Cross-Talk; Receptors, Estrogen; Receptors, FSH; Receptors, G-Protein-Coupled; Receptors, LH; Retrospective Studies; Selective Estrogen Receptor Modulators; Signal Transduction; Survival Analysis; Tamoxifen

Most ovarian cancers are estrogen-positive and hormonal treatments using anti-estrogens or aromatase inhibitors are under investigation for treating the tumors that are resistant to conventional therapies. In this study, the long-term effects of two anti-estrogens, namely 4-hydroxytamoxifen and fulvestrant (or ICI182,780), were investigated in ERα-positive BG1 epithelial ovarian cancer cells. To this aim, cells were grown in the presence of anti-estrogen concentrations that were sufficient to saturate the estrogen receptors, but were neither cytotoxic nor cytostatic as indicated by the absence of inhibition of cell proliferation. In these conditions and despite the lack of cytostatic effect of the drugs, long-term treatment (3 months) with the pure anti-estrogen fulvestrant induced a specific, reproducible and irreversible inhibition of ERα expression. This inhibition was accompanied by loss of estrogen-induced cell proliferation and gene expression as indicated by the analysis of several estrogen-responsive genes. ERα down-regulation was not linked to deregulated expression of transcription factors which drive ERα transcription and did not involve DNA methylation or histone deacetylation. Altogether, these results demonstrate that non-cytotoxic concentrations of pure anti-estrogens affect estrogen signaling and might be relevant for the treatment for ovarian cancers.

Topics: Cell Line, Tumor; Cell Proliferation; Estradiol; Estrogen Antagonists; Estrogen Receptor alpha; Estrogens; Female; Fulvestrant; Gene Expression Regulation; Humans; Ovarian Neoplasms; RNA, Messenger; Signal Transduction; Tamoxifen

Interactions between estrogen receptor signaling and the PI3K/Akt pathway are present in estrogen-dependent cancer cells. Therapeutical inhibition of each of these pathways has been proven to exert antitumoral effects. Inhibition of mammalian target of rapamycin (mTOR), a downstream target of Akt, is able to restore tamoxifen response in tamoxifen-resistant breast cancer cells. Given that Akt and mTOR phosphorylation also is frequently detected in ovarian and endometrial cancer, we intended to find out to what extent mTOR inhibitor RAD001 (everolimus) and tamoxifen add to each other's effects on growth and apoptosis of cancer cell lines derived from these tissues when given concomitantly.. OVCAR-3 and SK-OV-3 ovarian cancer cells, HEC-1A endometrial adenocarcinoma cells and MCF-7 breast cancer cells were treated with different concentrations of mTOR inhibitor RAD001 alone or in combination with 4-OH tamoxifen. Relative numbers of viable cells were assessed by means of the resazurin-based Cell Titer Blue assay, cellular apoptosis was examined by measurement of activated caspases 3 and 7 by means of the luminometric Caspase-Glo assay.. Treatment with RAD001 resulted in growth inhibition of all employed cancer cell lines in a dose-dependent manner, and SK-OV-3 ovarian cancer cells proved to be most sensitive to this drug. Moreover, we report the observation of additive, but not synergistical growth inhibitory effects of a combination treatment with RAD001 and 4-OH TAM on SK-OV-3 and OVCAR-3 ovarian cancer cells and MCF-7 breast cancer cells in vitro, whereas no such effect was observed in HEC-1A endometrial adenocarcinoma cells. Combination treatment with both drugs was demonstrated to be superior to single treatment with lower concentrations (0.1 and 1 nM) of RAD001 or standard concentrations of 4-OH TAM. Furthermore, RAD001 increased the apoptotic effect triggered by high 4-OH TAM concentrations in SK-OV-3 ovarian cancer cells.. Combination treatment with RAD001 and 4-OH TAM in vitro exerts an additive antitumoral effect on ovarian cancer cells and MCF-7 breast cancer cells. The significance of these data in the clinical situation has to be evaluated in further studies.

Topics: Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Breast Neoplasms; Cell Growth Processes; Cell Line, Tumor; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Drug Synergism; Endometrial Neoplasms; Everolimus; Female; Humans; Ovarian Neoplasms; Protein Kinases; RNA, Messenger; Sirolimus; Tamoxifen; TOR Serine-Threonine Kinases

Tamoxifen, which is widely used in the treatment of breast cancer, also has a beneficial effect on cisplatin-refractory ovarian cancer. In this study, we investigated the long-term effects of this drug on estrogen-receptor-positive ovarian cancer cells.. We performed an in vitro selection process by long-term treatment of BG-1 ovarian cancer cells with 4-hydroxy tamoxifen (4-OH TAM). Drug effects on cell growth were determined by measurement of relative cell numbers (MTS assay), the apoptotic effects of 4-OH TAM were determined by analysis of poly (ADP-ribose) polymerase (PARP) cleavage and by ELISA measurement of DNA-histone complexes in cytoplasm.. Analysis of BG-1(LT) ovarian cancer cells isolated after 5 months of long-term treatment with 4-OH TAM revealed both a significantly reduced apoptotic and antiproliferative effect of this drug. Further experiments to examine expression changes of the receptor tyrosine kinases EGFR, HER2 and estrogen receptor alpha did not reveal any alterations in BG-1(LT) if compared to wild-type cells. In contrast, in this cell line, a significant alteration in the expression of estrogen receptor beta was observed.. Our findings indicate that long-term treatment with 4-OH TAM is able to diminish both the antiproliferative and apoptotic action of this drug on BG-1 ovarian cancer cells. Our data suggest that the responsiveness of ovarian cancer cells to 4-OH TAM decreases after long-term treatment with this drug in vitro like previously observed after long-term treatment of breast cancer cells.

Topics: Apoptosis; Cell Growth Processes; Cell Line, Tumor; ErbB Receptors; Estrogen Receptor alpha; Estrogen Receptor beta; Female; Humans; Ovarian Neoplasms; Poly(ADP-ribose) Polymerases; Receptor Protein-Tyrosine Kinases; Receptor, ErbB-2; Receptors, Estrogen; Tamoxifen

Anthocyanins, which are natural plant pigments from the flavonoid family, represent substantial constituents of the human diet. Because some other bioflavonoids are known to have estrogenic activity, the aim of this study was to determine the estrogenic activity of the anthocyanine aglycones. Binding affinity to the estrogen receptor-alpha was 10,000- to 20,000-fold lower than that of the endogenous estrogen estradiol. In the estrogen receptor-positive cell line MCF-7, the anthocyanidins induced expression of a reporter gene. The tested anthocyanidins showed estrogen-inducible cell proliferation in two cell lines (MCF-7 and BG-1), but not in the receptor-negative human breast cancer cell line MDA-MB-231. The phytoestrogen-induced cell proliferation could be blocked by addition of the receptor antagonist 4-hydroxytamoxifen. Combination treatments with the endogenous estrogen estradiol resulted in a reduction of estradiol-induced cell proliferation. Overall, the tested anthocyanidins exert estrogenic activity, which might play a role in altering the development of hormone-dependent adverse effects.

Topics: Anthocyanins; Breast Neoplasms; Cell Division; Estradiol; Estrogen Receptor alpha; Estrogens; Estrogens, Non-Steroidal; Female; Gene Expression; Humans; Isoflavones; Ovarian Neoplasms; Phytoestrogens; Plant Preparations; Receptors, Estrogen; Tamoxifen; Transcription, Genetic; Tumor Cells, Cultured

Estrogens are mitogens that stimulate the growth of both normal and transformed epithelial cells of the female reproductive system. The effect of estrogens is mediated through the estrogen receptors, which are ligand-regulated transcription factors. Tamoxifen, a selective estrogen receptor modulator, functions as an estrogen receptor antagonist in breast but an agonist in uterus. In the current study, we show that coexpression of a constitutively active MEKK1, but not RAF or MEKK2, significantly increases the transcriptional activity of the receptor in endometrial and ovarian cancer cells. The expression of wild-type MEKK1 and an active Rac1, which functions upstream of MEKK1, also increased the activity of the receptor while coexpression of dominant negative MEKK1 blocked the Rac1 induction, indicating that endogenous MEKK1 is capable of activating the receptor. Additional experiments demonstrated that the MEKK1-induced activation was mediated through both Jun N-terminal kinases and p38/Hog1 and was independent of the known phosphorylation sites on the receptor. p38, but not Jun N-terminal kinases, efficiently phosphorylated the receptor in immunocomplex kinase assays, suggesting a differential involvement of the two kinases in the receptor activation. More importantly, the expression of the constitutively active MEKK1 increased the agonistic activity of 4-hydroxytamoxifen to a level comparable to that of 17beta-estradiol and fully blocked its antagonistic activity. These findings suggest that the uterine-specific agonistic activity of the tamoxifen compound may be determined by the status of kinases acting downstream of MEKK1.

Topics: Endometrial Neoplasms; Enzyme Activation; Enzyme Inhibitors; Estrogen Antagonists; Estrogen Receptor alpha; Female; Flavonoids; Humans; Imidazoles; JNK Mitogen-Activated Protein Kinases; MAP Kinase Kinase Kinase 1; MAP Kinase Kinase Kinase 2; MAP Kinase Kinase Kinases; Mitogen-Activated Protein Kinases; Ovarian Neoplasms; p38 Mitogen-Activated Protein Kinases; Phosphorylation; Protein Serine-Threonine Kinases; Proto-Oncogene Proteins c-raf; Pyridines; Receptors, Estrogen; Tamoxifen; Transcription, Genetic; Tumor Cells, Cultured

The human estrogen receptor (ER) is a ligand-inducible transcription factor that contains two transcriptional activation functions, one located in the NH2-terminal region of the protein (AF-1) and the second in the COOH-terminal region (AF-2). Antiestrogens, such as trans-hydroxytamoxifen (TOT), have partial agonistic activity in certain cell types, and studies have implied that this agonism is AF-1-dependent. We have made progressive NH2-terminal and other segment deletions and ligations in the A/B domain, and studied the transcriptional activity of these mutant ERs in ER-negative MDA-MB-231 human breast cancer and HEC-1 human endometrial cancer cells. Using several estrogens and several partial agonist/antagonist antiestrogens, we find that estrogens and antiestrogens require different regions of AF-1 for transcriptional activation. Deletion of the first 40 amino acids has no effect on receptor activity. Antiestrogen agonism is lost upon deletion to amino acid 87, while estrogen agonism is not lost until deletions progress to amino acid 109. Antiestrogen agonism has been further defined to require amino acids 41-64, as deletion of only these amino acids results in an ER that exhibits 100% activity with E2, but no longer shows an agonist response to TOT. With A/B-modified receptors in which antiestrogens lose their agonistic activity, the antiestrogens then function as pure estrogen antagonists. Our studies show that in these cellular contexts, hormone-dependent transcription utilizes a range of the amino acid sequence within the A/B domain. Furthermore, the agonist/antagonist balance and activity of antiestrogens such as TOT are determined by specific sequences within the A/B domain and thus may be influenced by differences in levels of specific factors that interact with these regions of the ER.

Topics: Binding Sites; Breast Neoplasms; Estradiol; Estrogen Antagonists; Estrogens; Female; Gene Expression Regulation; Gene Expression Regulation, Neoplastic; Humans; Ligands; Ovarian Neoplasms; Receptors, Estrogen; Sequence Deletion; Structure-Activity Relationship; Tamoxifen; Transcription, Genetic; Transcriptional Activation; Tumor Cells, Cultured

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.

Topics: Cathepsin D; Cell Division; Dihydrotestosterone; Electrophoresis, Polyacrylamide Gel; Enzyme Precursors; Estradiol; Estrogen Antagonists; Female; Humans; Molecular Weight; Ovarian Neoplasms; Precipitin Tests; Proteins; Tamoxifen; Tumor Cells, Cultured

The influence of estrogen (E) and antiestrogen (AES) on the in vitro growth of BG-1 ovarian carcinoma cells, which express steroid receptors was examined (K. R. Geisinger, T. E. Kute, M. J. Pettenati, C. E. Welander, Y. Dennard, L. A. Collins, and M. E. Berens, Characterization of a human ovarian carcinoma cell line with estrogen and progesterone receptors, Cancer 63, 280-288, 1989). All determinations were simultaneously referenced under similar conditions to MCF-7 cells, a well-established cell line for modeling hormonal responses in breast cancer. In "complete" media containing fetal calf serum (FCS, 10%), MCF-7 cell numbers increased approximately 7 x in 7 days, remaining at this level Days 8-15. In contrast, BG-1 cells achieved similar numbers by Day 7, but showed apparent exponential growth over Days 8-15 to 15-20 x. Phenol red-free media containing 10% FCS (less than 20 pg estradiol (E2)/ml by RIA) was used to assess responses to E and AES. Growth of both MCF-7 and BG-1 cells slowed in E-free media. E2 (10 nM) stimulated the growth of both cell lines, yet was responsible for exponential increases during Days 8-15 only in BG-1 cell numbers (50-70 x). The metabolically active AES (4OH-tamoxifen, 50 nM) reduced E2-stimulated MCF-7 growth to 3-4 x, while tamoxifen (50 nM) had no effect. Rescue with 10 microM E2 fully overcame the AES inhibition of MCF-7 proliferation. In contrast, BG-1 cells experienced significant E2-stimulated growth reductions in the presence of either 4OH-tamoxifen or tamoxifen. E2 was observed to rescue BG-1 cells from both of these antagonists. We conclude that BG-1 ovarian carcinoma cells respond in vitro to E and AES. Moreover, by virtue of responses to tamoxifen, BG-1 cells may have an intrinsic capacity to hydroxylate tamoxifen to its active metabolite. This property of ovarian carcinoma cells might be worth exploiting in the design of more effective combination chemotherapy regimens.

Topics: Carcinoma; Cell Division; Culture Media; Estradiol; Estrogen Antagonists; Estrogens; Female; Humans; Ovarian Neoplasms; Tamoxifen; Tumor Cells, Cultured

An epithelial ovarian cancer cell line, PE04, has been shown to contain high levels of cytosolic estrogen receptor-like binding. Analysis of PE04 cytosol on low-salt sucrose density gradients demonstrated 7-9S binding of [3H]17 beta-estradiol, with specificity consistent with that of an estrogen receptor. When compared with the proliferation of cells grown in monolayer without steroids, a 50% increase in growth rate of the cell line was observed by treatment with 17 beta-estradiol (E2). Growth stimulation was dose-dependent and maximal at 10(-10) M. The E2 effect on substrate-independent growth was more striking; 3 x 10(-9) M produced a 30-fold increase in cloning efficiency. Treatment with 4-hydroxytamoxifen resulted in a dose-dependent inhibition (maximal at 3 x 10(-9) M) of cell growth, which was reversible by E2. Although treatment with estrogen in systems containing functional estrogen receptor commonly results in progesterone receptor synthesis, E2 induction of progesterone receptor could not be demonstrated in this cell line. The endocrine characteristics of PE04 contrast with those of another ovarian cancer cell line, NIH:OVCAR-3, in which E2 induces progesterone receptor but does not stimulate cell proliferation. This is the first report of an ovarian cancer cell line in which the clinically important end-effect of estrogen, cell growth, has been observed. Furthermore, retention of a mitogenic response to estrogen in the apparent absence of progesterone receptor induction has not been described previously in model systems.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adenocarcinoma, Mucinous; Cell Division; Cell Line; Dose-Response Relationship, Drug; Estradiol; Estrogen Antagonists; Estrogens; Female; Humans; Ovarian Neoplasms; Promegestone; Receptors, Estrogen; Tamoxifen; Time Factors; Tumor Cells, Cultured

The steroid hormone receptor content of 32 malignant ovarian tumors was compared with the in vitro effectiveness of 4 hydroxytamoxifen (OH-TAM) and medroxy-progesterone acetate (MPA) tested in the Human Tumor Colony Forming Assay (HTCFA). The sensitivity for the receptor determination was 5 fmol/mg cytosol protein. Estrogen receptors (ER) and progesterone receptors (PR) were found in 15 (47%) and 13 (41%) of the tumors respectively. As standard criteria for the HTCFA, a minimum of 30 colonies with a diameter of more than 60 microns and 100 microns was used in the control group. The in-vitro sensitivity of ovarian tumors to OH-TAM and MPA was independent on the ER or PR content, and amounted to 9% for OH-TAM and 6% for MPA. However, all 12 ER-PR-tumors proved resistant to OH-TAM and MPA. 18 ovarian tumors showed a sufficient colony growth, even in the size class exceeding 100 microns. With a minimum colony size of 60 microns and 100 microns, 17% and 33% respectively were sensitive to OH-TAM. A similar effect on the proliferative capacity of the Tumor Colony Forming Units (TCFUs), unrelated to PR, was observed with MPA. Dependent on colony size, we found an increasing sensitivity against MPA from 11% to 22%. The in-vitro effectiveness of both OH-TAM and MPA in the clonogenic assay of malignant ovarian tumors was certainly not as potent as suggested by the results obtained in biochemical steroid hormone receptor analysis. To prove the hormonal response in the HTCFA, it is necessary to determine number and size of the colonies as an expression of their proliferative potential.

Topics: Adenocarcinoma; Colony-Forming Units Assay; Cystadenocarcinoma; Female; Granulosa Cell Tumor; Humans; Krukenberg Tumor; Medroxyprogesterone; Medroxyprogesterone Acetate; Neoplasms, Hormone-Dependent; Ovarian Neoplasms; Receptors, Estrogen; Receptors, Progesterone; Tamoxifen; Tumor Cells, Cultured

As previously reported, ovarian epithelial carcinomas may respond to endocrine therapy. We examined the direct effect of progesterone, medroxyprogesteroneacetate, gestoneron, 17-beta-estradiol, tamoxifen, 4-OH-tamoxifen, or N-desmethyltamoxifen on the proliferative capacity of ovarian carcinoma cells by means of the colony assay described by Hamburger and Salmon. The growth rate of 25 tested tumors (ascitic fluid, primary tumor, metastases) was 68%. The plating efficiency was 0.078%. Beside the drug testing estrogen and progesterone receptor levels were determined. The inhibition of colony survival was slightest with 17-beta-estradiol, more pronounced with medroxyprogesteroneacetate, gestoneron, N-desmethyltamoxifen, and progesterone, and greatest with 4-OH-tamoxifen and tamoxifen. Significant and dose-dependent inhibition of greater than 70% was observed with tamoxifen and 4-OH-tamoxifen in 80% of the tested tumors. There was no significant correlation between the in vitro responsiveness and the level of hormonal act not only via an estrogen receptor but also via an antiestrogen-binding site.

Topics: Adenocarcinoma; Aged; Cell Division; Cells, Cultured; Estradiol; Estrogen Antagonists; Ethanol; Female; Gestonorone Caproate; Humans; Medroxyprogesterone; Medroxyprogesterone Acetate; Middle Aged; Neoplasm Metastasis; Neoplastic Stem Cells; Ovarian Neoplasms; Progesterone; Receptors, Estrogen; Receptors, Progesterone; Tamoxifen

Methods and evaluation of the human tumor stem cell assay (HTSCA) are described. Advantages and disadvantages of the test system are elaborated. The in vitro/in vivo correlation in the drug screening of human ovarian carcinomas shows that the prediction of sensitivity to a cytotoxic agent is only possible in 64%. Prediction of drug resistance, however, seems to be possible in 95%. The number of patients that profit from the HTSCA seems to be only less than 10%. Our investigations describe the influence of various hormones and antiestrogens on the colony formation of human ovarian carcinoma cells. Tamoxifen and his major metabolite 4-hydroxy-tamoxifen were the most active agents. Both compounds inhibit the colony survival (70% at pharmacological concentrations) of 60% of the screened ovarian carcinomas. A significant correlation to the quantitative level of estrogen or progesterone receptors could not be proved. Colony formation of ovarian carcinoma cells was compared in the HTSCA as described by Hamburger and Salmon and in a methylcellulose-monolayer system. Our results show that the colony formation corresponds to the results of the original HTSCA: Cloning ovarian carcinoma cells in the methylcellulose-monolayer, however, seems to be technically easier and faster.

Topics: Agar; Antineoplastic Agents; Carcinoma; Cells, Cultured; Colony-Forming Units Assay; Drug Resistance; Estradiol; Female; Hormones; Humans; Medroxyprogesterone; Medroxyprogesterone Acetate; Methylcellulose; Ovarian Neoplasms; Progesterone; Prognosis; Tamoxifen; Tumor Stem Cell Assay

A monoclonal antibody (D-547) against human breast cancer oestrogen receptor was used to demonstrate that the oestrogen receptor in ovarian epithelial carcinomata binds [3H]monohydroxytamoxifen. This binding was observed in sedimentation velocity analyses of both cytosol and nuclear compartments. Binding of [3H]monohydroxytamoxifen to the antibody-recognized moiety could be inhibited by diethylstilboestrol or oestradiol, but not by androgen, progestin or corticoid, indicating oestrogen specificity for the binding site. The sedimentation coefficient of the antibody-recognized [3H]monohydroxytamoxifen binding moiety was similar to that when 16 alpha-[125I]iodo-oestradiol was used as the ligand.

Topics: Antibodies, Monoclonal; Centrifugation, Density Gradient; Estradiol; Estrogen Antagonists; Female; Humans; Ovarian Neoplasms; Receptors, Estrogen; Tamoxifen