Evaluation Of Estrogen Receptor Research Articles

Quantitation of estradiol receptors alpha and beta and progesterone receptors in human breast tumors by real-time reverse transcription-polymerase chain reaction: Correlation with protein assays

Hormone receptor content is the most useful parameter for predicting hormone response therapy in breast cancer. The high frequency of primary and secondary resistance to treatment makes it necessary to find out other parameters in order to improve the prediction of response to treatment. The newly described estrogen receptor β (ERβ) is a potential candidate. Using real-time quantitative RT-PCR, we evaluated estrogen receptor α (ERα), ERβ, and progesterone receptors (PR) in comparison with ERα and PR protein content measured with the enzyme immunoassay (EIA), in a retrospective series of 98 breast tumors. We obtained a highly significant correlation between mRNA and EIA assays for ERα and PR ( r=0.79 and r=0.71, respectively; P<0.001). We confirmed the low level of ERβ mRNA transcripts in comparison to ERα in breast tumors. We did not find any statistically significant correlation between the absolute ERβ mRNA level and ERα or PR mRNA level, and ERα or PR-EIA. We found a significant correlation between ERα mRNA and PR mRNA expressions. We did not find any correlation between ERβ mRNA and clinical features of the patients (age, menopausal status, tumor size, and nodal status), nor with the histological type of the tumor. In conclusion, the accuracy of the present quantitative RT-PCR assay makes it suitable for a routine clinical use. In addition, the present results suggest that, ERβ mRNA expression is independent of the classical parameters.

The 1993–94 patterns of care process survey for breast irradiation after breast-conserving surgery—comparison with the 1992 standard for breast conservation treatment

Purpose: To determine the patterns of evaluation and treatment in the U.S. of women with early breast cancer treated with breast-conserving surgery and irradiation in 1993–94, and to compare these with a similar survey in 1983 and with the 1992 Standard for Breast Conservation Treatment. Methods and Materials: In 1995–96, 727 randomly selected records of eligible patients treated from 1993–94 at 62 facilities representative of 3 practice types were reviewed. Results: Compared with the Process Survey (PS) in 1983, patients in the 1993–94 study had an older age distribution. In the current study, 70% of patients were ≥ 50 years of age, and 69% were post-menopausal, compared with 59% ≥ 50 years of age and 49% post-menopausal in 1983 ( p = 0.0087 and < 0.001, respectively). Work-up and evaluation in the 1993–94 PS were closely aligned with the standard and were considerably improved compared with 1983. In the 1983 study, 77% of patients underwent mammography, as compared to 97% in the 1993–94 study. In 1983, pathological size documentation was performed in 83% of patients; in 1993–94, this was performed in 95% of patients. An estrogen receptor evaluation was performed in 36% of patients in 1983; in 1993–94, that increased to 76%. In 1983, 28% of patients underwent progesterone receptor evaluation; in 1993–94, this increased to 72%. Only 3% of patients in 1993–94 were enrolled in a clinical trial. Radiation treatment parameters closely adhered to standard recommendations, improving substantially from 1983. In 1983, wedge or compensator use was recommended for 64% of patients; in 1993–94, for 95% of patients. In 1983, 4–8 MV photons were recommended for breast treatment in 67% of patients; in 1993–94, 90%. In 1983, bolus was avoided in 75% of patients; in 1993–94, in 94%. In 1983, the recommended breast dose for 89% of patients was 45–50 Gy (44–51 Gy in PS); in 1993–94 this had increased to 99% of patients. In 1983, electrons were recommended for primary site boost in 70% of patients; in 1993–94, for 94% of patients. Conclusion: There was an extensive shift to adherence to the 1992 standard in 1993–94, compared with the 1983 PS, although there is room for improvement in some areas.

Molecular markers for predicting response to tamoxifen in breast cancer patients.

Tamoxifen is one of the most effective treatments for breast cancer. Standard practice is to select patients who are likely to respond to this therapy through the evaluation of estrogen receptor (ER) and progesterone receptor (PR) in the primary tumor tissue. Over the past 25 yr that physicians have been using ER determination to guide tamoxifen use, numerous studies have demonstrated that this molecular marker is useful in predicting benefit from tamoxifen. ER has been analyzed for many years using ligand-binding assays. However, current practice involves the use of immunohistochemical-based assays to detect ERalpha Immunohistochemistry (IHC) has several advantages. For example, IHC evaluates tumor cell heterogeneity, can be used to study small samples, is less expensive, and allows direct correlation with multiple histopathological tumor features and other molecular markers. PR, an estrogen-responsive protein, can also be useful in predicting response to tamoxifen in specific clinical situations. In recent years, several other markers of tamoxifen response have been examined, including: pS2 (another estrogen-regulated protein), heat-shock proteins 27 and 70, bcl-2 protein, c-erbB-2 (HER-2/neu) oncoprotein, and mutated p53 tumor suppressor protein. In this article, we present an analysis of the data on these new molecular markers. Overall, from numerous studies, the data indicate that in addition to ERalpha bcl-2 is a potential candidate to help further improve our ability to predict response to tamoxifen. ER and bcl-2 are the most useful molecular markers to better identify breast cancer patients who will respond to tamoxifen and who will have prolonged survival.

Densitometric measurement in absolute values of estrogen receptors by immunohistochemistry in breast cancer frozen sections

Immunohistochemical evaluation is, at present, the most reliable method to evaluate estrogen receptors (ERs) in breast cancer samples. Various quantitative 'scoring' systems have been developed to evaluate both the percentage of ER-positive nuclei and the staining intensity. However, such methods show a high interobserver variability. Densitometric evaluation of ERs provides objective results; however, it is scarcely reproducible because results are expressed in arbitrary units. Reproducibly to quantitate, as fmol/mg protein, the cell content of ERs detected by immunohistochemistry in frozen sections of breast cancer, we set up a densitometric method by using the MCF-7 cell cultures as standard. MCF-7 cell cultures were stimulated with insulin and insulin-like growth factor (IGF-1) to express variable concentrations of ERs. To reveal ERs with the same antibody clone, the immunoenzymatic study was carried out by using the ER-EIA method, whereas immunohistochemical reactions were based on ER-immunocytochemical assay (ICA) method. A standard curve, obtained by plotting the ER fmol/mg protein (by the enzymatic assay in MCF-7 cells) versus the optical-density values (by analyzing the immunohistochemical stain on MCF-7 cytospins), was the reference of our method. This method was validated on four cases of human infiltrating breast carcinoma, and no statistically significant differences were observed between ER concentration measured with the EIA method and that obtained by immunohistochemistry.

Evaluation of estrogen receptor, antiestrogen binding sites and calmodulin for antiestrogen resistance of two clones derived from the MCF-7 breast cancer cell line

Estrogen receptor (ER), antiestrogen binding sites (AEBS) and calmodulin (CaM) are potential targets of antiestrogen (AE) action. To analyse further which of these targets are primarily involved in the antiproliferative activity of these drugs against human breast cancers, two cell clones, namely the RTx6 and LY-2 variants, selected from MCF-7 cells for their resistance to high doses of tamoxifen (TAM) and the Keoxifen (KEO) analog LY 117018, respectively, were studied for their sensitivity to hydroxytamoxifen (OH-TAM) and KEO as well as the strong calmodulin antagonist calmidazolium. The effects of these drugs on both cell growth and progesterone receptor (PgR) concentration were assessed. Binding properties for ER, AEBS and CaM of each compound were also measured. Our results confirmed that basal growth of RTx6 and LY-2 cells was more resistant to OH-TAM and KEO than parent MCF-7 cells, although both displayed a significant inhibition at the highest doses assessed. In regard to calmidazolium inhibition, each variant behaved as did the MCF-7 line indicating that a modification at the CaM level was not responsible for their lower sensitivity to AEs. Nor could the association of CaM to ER which did not differ among all cell lines. Resistance of these variants was not related to AEBS in view of the total lack of such sites in RTx6 cells. However, under estrogenic growth stimulation such sites may play some role, since LY-2 cells in the presence of estradiol displayed a real antiestrogen-resistant pattern while RTx6 cells were more sensitive than MCF-7 cells to OH-TAM. This property was not found in the antagonism against estradiol-induced PgR synthesis which was observed with each variant. Thus the PgR concentration of RTx6 cells was strongly down-regulated by OH-TAM and KEO and reduced in LY-2 cells to the same extent as in MCF-7 cells. All these observationsshow that AE resistance is not entirely related to ER mediated events and that alterations at the ER and CaM levels are unlikely to account for the lower AE sensitivity of the variants investigated.

Immunohistochemical analysis of estrogen and progesterone receptors in endometrium and peritoneal endometriosis: a new quantitative method

To evaluate estrogen receptors (ER) and progesterone receptors (PR) content in glandular and stromal cells of eutopic and ectopic endometrium. A recently advanced stereographic computer technology was applied for the investigation of steroid receptors. University hospital department of gynecology. Biopsies of endometrium and typical peritoneal endometriotic lesions were taken from 19 infertile patients with laparoscopically proved endometriosis. Endometrial biopsies were also taken from 15 patients without endometriosis. All of them were untreated. In normal endometrium, the highest concentrations of ER and PR occurred in the epithelial and stromal cells during the late proliferative phase of the menstrual cycle. Estrogen receptor and PR content declined throughout the secretory phase. Progesterone receptor content was found not to be significantly decreased in the stroma during the early secretory phase and quite high in the late secretory phase. In peritoneal endometriotic lesions, the highest concentrations of ER and PR were found during the late proliferative phase. When compared with normal endometrium, a lower ER content ans a similar PR content were observed, and the cyclic changes in peritoneal endometriosis lesions were also similar. A new computerized technology for the evaluation of ER and PR in eutopic and ectopic endometrium. Although the ER content was found to be lower in endometriotic tissue when compared with endometrium, the cyclic pattern was similar in both eutopic and ectopic endometrium. Progesterone receptor content was similar in both tissues, except during the late secretory phase in ectopic glandular epithelium in which a high persistent PR content was observed.

Steroid Therapy and the Endometrium: Biological and Clinical Implications

The benefits of estrogen replacement therapy in postmenopausal women include increased quality of life, relief from specific symptoms, and the prevention of osteoporosis, genitourinary atrophy, and cardiovascular diseases. Despite these advantages, this therapy has been reported to be associated with an increased frequency of endometrial hyperplasia and adenocarcinoma. In order to evaluate a possible relationship between the histological findings and stroma-derived growth regulators, 19 endometrial samples obtained from women undergoing both percutaneous (n = 11) and oral (n = 8) steroid replacement therapy were processed for histological and immunocytochemical evaluation of estrogen receptor (Er), progesterone receptor (Pr), and epidermal growth factor receptor (EGFr). Transdermal estradiol was given for 21 days and 10 mg medroxyprogesterone acetate (MAP) were added to the last 12 days; conjugated equine estrogens were given for 21 days and 10 mg MAP added to the last 12 days. Endometrial samples were obtained between days 17-18 of the sixth month of therapy. Proliferative and hyperplastic endometria showed immunoreactivity against Er, Pr, and EGFr. Atrophic endometria were always negative by immunocytochemistry. Our results suggest: 1) a relationship between histological findings and the receptor examined; 2) a crucial role for EGF in the regulation of endometrial proliferation.

A simple method for estrogen receptor antigen preservation in cytologic specimens containing breast carcinoma cells

We report a modified method to prepare cytologic specimens for the evaluation of estrogen receptors by immunocytochemistry. Cytologic samples were obtained by needle aspiration of tumor masses (nine patients) and body cavity fluids (nine patients). The cytologic material was divided, and slides for immunostaining were prepared according to two different techniques: (1) fixation of cells in suspension (modified method); and (2) fixation of cells adherent to slides (standard method). The results after immunostaining demonstrated that the number of cells adhering to slides prepared according to the modified method was greatly increased as compared with the number of cells remaining attached to slides prepared according to the standard method. There was no loss of cell groups or aggregates using the modified method. The antigenicity of estrophilin and the cell morphology were well-preserved for up to 30 days. With this modified method, cytologic samples may be stored and conveniently processed in batches, thereby improving the utilization of laboratory resources.

Comparative Evaluation of ER-ICA and Enzyme Immunoassay for the Quantitation of Estrogen Receptors in Breast Cancer

Evaluation of estrogen receptors (ERs) is essential for the treatment and prognosis of human breast cancer. The authors have undertaken a study of 225 primary breast cancers to compare the receptor values using immunohistochemistry and enzyme immunoassay (EIA) techniques. The results are compared with the biochemical assay with the use of the dextran-coated charcoal (DCC) method done on the same specimens. The overall concordance between ER-ICA and DCC was 77%. Ninety-seven percent concordance was observed for specimens with a positive ER-ICA score (greater than 70 and the DCC more than 10 fmol/mg protein). Ninety-two percent of tumors had negative results by ER-ICA when the DCC was less than 10 fmol/mg protein. When the ER-ICA score was plotted against the DCC or EIA value, a significant correlation was obtained with a P value of less than 0.001. The correlation between the ER-ICA score and the total ER content (cytosol and nuclear) assayed by EIA was similar to comparison with cytosol alone. The authors conclude that the ER-ICA can be useful in assessing ERs in breast especially in hypocellular or small tumors and in assessing the degree of heterogeneity in a given tumor. The immunohistochemical and biochemical assay methods are complementary and provide greatly needed information for the management of breast cancer.

Clinical Response to Busramustine (KM-2210) in Chronic Lymphocytic Leukemia: A Pilot Evaluation of Estrogen Receptor in Relation to Its Therapeutic Effect

Busramustine (KM-2210), the benzoate of a 17 beta-estradiol-chlorambucil conjugate, was administered to 11 patients with chronic lymphocytic leukemia (CLL) which included eight cases of B-cell CLL and three cases of T-cell CLL. Four patients had received prior chemotherapy. Busramustine was given orally at an initial daily dose of 50-100 mg continuously, and the dose was modified according to hematological improvement. Two cases of B-cell CLL achieved clinical complete responses, six cases including two of T-cell CLL and four of B-cell CLL achieved partial responses and one case of B-cell CLL achieved improvement. The partial and complete response rate was 72.7%. Four patients showed estrogen receptor activity of CLL cells ranging from 3.5 to 57.5 fmol/mg cytosol protein, but there seemed to be no correlation between the estrogen receptor activity of the CLL cells and the therapeutic effects of busramustine. Toxic effects included diarrhea (2/11) and estrogen-related symptoms including breast pain (4/11), genital bleeding (2/5), gynecomastia (2/6) and loss of libido (2/6). The findings of this preliminary study suggest that busramustine is effective in the treatment of CLL, irrespective of the presence of the estrogen receptor.

The Evaluation of Estrogen Receptor in Primary Breast Carcinoma by Computer-Assisted Image Analysis

A monoclonal antibody prepared against estrogen receptor has been shown to be specific and sensitive for the detection of estrogen receptor in human breast lesions by use of immunohistochemical methods. Two hundred selected cases of primary breast carcinoma were assayed for estrogen receptor content by biochemical and immunohistochemical procedures. Quantitative evaluation was by biochemical, immunohistochemical, and automated computer-assisted image analysis using the Cell Analysis System's CAS/100 machine (Lombard, IL). Quantitative estrogen receptor content was determined by dextran-coated charcoal analysis and sucrose density gradient analysis. Immunohistochemical evaluation incorporated both intensity and distribution of staining, yielding a subjective score, histologic score (HSCORE). An objective quantitation, also incorporating intensity and distribution of staining, was done by computer-assisted image analysis, quantitative immunocytochemical score (QIC SCORE). HSCORE analysis was done with and without methyl green counterstain with no loss of sensitivity. Comparison of QIC SCORE with the biochemical and immunohistochemical analysis of the tissues examined revealed excellent sensitivities and specificities. These data suggest that automated image analysis provides an effective qualitative and quantitative means of evaluating estrogen receptor content in human breast cancers.

Evaluation of estrogen receptors by immunocytochemistry on fine-needle aspiration biopsy specimens from breast tumors.

The estrogen receptor (ER) content of 31 surgically removed breast tumors (26 duct carcinomas, one lobular carcinoma, one papillary carcinoma, one colloid carcinoma, one duct carcinoma in situ, and one atypical fibroadenoma) was determined by a commercially available immunocytochemical method (Abbott Laboratories, ER-ICA) on cytologic material obtained by fine needle aspiration biopsy (FNAB) of surgical specimens. Immunocytochemical staining of cells by a peroxidase-antiperoxidase technique was evaluated on the basis of the percentage of positive cells and the intensity of staining. An immuno-staining score for cytologic (IS-CYTO) and histologic (IS-HISTO) material was defined and a threshold of positivity determined to facilitate the semi-quantitation of results and the comparison of cases. The results of immunostaining of cytologic material were compared with the evaluation of ER in corresponding tissue samples as determined by the radioligand binding assay using the dextran-coated charcoal procedure (ER-DCC) and by ER-ICA using cryostat sections of frozen tissue. The sensitivity, specificity, predictive value of a positive test, and test efficiency of ER-ICA in cytologic material as compared to ER-DCC was 96%, 83%, 96% and 93%, respectively. The IS-CYTO was significantly correlated with the IS-HISTO in corresponding histologic material (r = 0.72, P less than 0.001). In conclusion, the combination of ER-ICA with FNAB represents a useful new technique for the evaluation of ER which may be applied to small primary tumors, tumor recurrences, and metastases.

Evaluation of estrogen receptor in human prostate

Evaluation of estrogen receptor in human prostate

Bilateral ovariectomy in premenopausal patients with advanced breast cancer, after the evaluation of estrogen receptors and urinary androgen excretion

Eighty premenopausal patients with advanced breast cancer underwent bilateral ovariectomy. Clinical response was evaluated at 6 months from the operation and correlated with the presence or absence both of estrogen receptors and of elevated urinary androgen excretion. The results obtained show that both parameters considered are actually significant to predict the clinical response to ovariectomy, especially when both of them are concordant.