Demonstration of oestrogen receptors in paraffin wax sections of breast carcinoma using the monoclonal antibody 1D5 and microwave oven processing

The Co-Expression of Estrogen Receptors ERα, ERβ, and GPER in Endometrial Cancer

Estrogens have important roles in endometrial cancer (EC) and exert biological effects through the classical estrogen receptors (ERs) ERα and ERβ, and the G-protein-coupled ER, GPER. So far, the co-expression of these three types of ERs has not been studied in EC. We investigated ERα, ERβ, GPER mRNA and protein levels, and their intracellular protein distributions in EC tissue and in adjacent control endometrial tissue. Compared to control endometrial tissue, immunoreactivity for ERα in EC tissue was weaker for nuclei with minor, but unchanged, cytoplasmic staining; mRNA and protein levels showed decreased patterns for ERα in EC tissue. For ERβ, across both tissue types, the immunoreactivity was unchanged for nuclei and cytoplasm, although EC tissues again showed lower mRNA and protein levels compared to adjacent control endometrial tissue. The immunoreactivity of GPER as well as mRNA levels of GPER were unchanged across cancer and control endometrial tissues, while protein levels were lower in EC tissue. Statistically significant correlations of estrogen receptor α (ESR1) versus estrogen receptor β (ESR2) and GPER variant 3,4 versus ESR1 and ESR2 was seen at the mRNA level. At the protein level studied with Western blotting, there was significant correlation of ERα versus GPER, and ERβ versus GPER. While in clinical practice the expression of ERα is routinely tested in EC tissue, ERβ and GPER need to be further studied to examine their potential as prognostic markers, provided that specific and validated antibodies are available.

Hemagglutinin protease secreted by V. cholerae induced apoptosis in breast cancer cells by ROS mediated intrinsic pathway and regresses tumor growth in mice model

Conventional anticancer therapies are effective but have side effects, so alternative targets are being developed. Bacterial toxins that can kill cells or alter the cellular processes like proliferation, apoptosis and differentiation have been reported for cancer treatment. In this study we have shown antitumor activity of hemagglutinin protease (HAP) secreted by Vibrio cholerae. One µg of HAP showed potent antitumor activity when injected into Ehrlich ascites carcinoma (EAC) tumors in Swiss albino mice. Weekly administration of this dose is able to significantly diminish a large tumor volume within 3 weeks and increases the survival rates of cancerous mice. HAP showed apoptotic activity on EAC and other malignant cells. Increased level of pro-apoptotic p53 with increased ratio of pro-apoptotic Bax to anti-apoptotic Bcl-2 signify that HAP induced apoptogenic signals lead to death of the tumor cells. In vivo and ex vivo studies suggest that mitochondrial dependent intrinsic pathway is responsible for this apoptosis. The level of ROS in malignant cells is reported to be higher than the normal healthy cells. HAP induces oxidative stress and increases the level of ROS in malignant cells which is significantly higher than the normal healthy cells. As a result the malignant cells cross the threshold level of ROS for cell survival faster than normal healthy cells. This mechanism causes HAP mediated apoptosis in malignant cells, but normal cells remain unaltered in the same environment. Our study suggests that HAP may be used as a new candidate drug for cancer therapy.

Prognostic Biomarkers and EBV Infection Research in Diffuse Large B-Cell Lymphoma of the Palatine Tonsils

Diffuse large B-cell lymphoma represents approximately 30%–40% of all diagnoses of non-Hodgkin's Lymphoma and may represent up to 80% of all lymphomas that arise in the palatine tonsils. Several studies have attempted to correlate clinical, laboratorial, and tissue factors with the prognosis of the lymphomas, such as the International Prognostic Index, the tissue expression of some proteins, and the lymphocyte count at the time of diagnosis, as well as to correlate Epstein-Barr virus (EBV) infection with worse prognoses. Patients with palatine tonsil DLBCL, from Salvador, Bahia, Brazil, were studied in order to identify prognostic factors. Twenty-four patients with DLBCL were studied. The factors that negatively influenced the patients' survival rates were the lymphocyte count at the time of diagnosis <1.000/mm³ and the Bcl-2 protein expression. There was no CD5 expression in these lymphomas, and neither was there an association with EBV infection.

Adenocarcinoma of the esophagogastric junction: relationship between clinicopathological data and p53, cyclin D1 and Bcl-2 immunoexpressions

CONTEXT

Esophagogastric junction adenocarcinoma has an aggressive behavior, and TNM (UICC) staging is not always accurate enough to categorize patient's outcome.

OBJECTIVES

To evaluated p53, cyclin D1 and Bcl-2 immunoexpressions in esophagogastric junction adenocarcinoma patients, without Barrett's esophagus, and to compared to clinicopathological characteristics and survival rate.

METHODS

Tissue sections from 75 esophagogastric junction adenocarcinomas resected from 1991 to 2003 were analyzed by immunohistochemistry for p53, cyclin D1 and Bcl-2 using streptavidin-biotin-peroxidase method. The mean follow-up time was 60 months SD = 61.5 (varying from 4 to 273 months).

RESULTS

Fifty (66.7%) of the tumors were intestinal type and 25 (33.3%) were diffuse. Vascular, lymph node and perineural infiltration were verified in 16%, 80% and 68% of the patients, respectively. The patients were distributed according to the TNM staging in IA in 4 (5.3%), IB in 10 (13.3%), II in 15 (20%), IIA in 15 (20%), IIIB in 15 (20%) and IV in 16 (21.3%). Immunohistochemical analysis was positive for p53, cyclin D1 and bcl-2 in 68%, 18.7% and 100%, respectively. There was no association between immunoexpression and vascular and/or perineural invasions, clinicopathological characteristics and patients' survival rate.

CONCLUSION

In this selected population, there was no association between the immunomarkers, p53, cyclin D1 and bcl-2 and clinicopathological data and/or overall survival.

[Expression of cell proliferation and apoptosis biomarkers in skin spinocellular carcinoma and actinic keratosis]

BACKGROUND

Skin cancer is the most frequent type of human cancer and has shown an increase in its incidence. In many cases, before the onset of the carcinoma, there might be a precursor lesion--actinic keratosis, which can develop into squamous cell carcinoma. Studies have been carried out in order to determine the parameters that have prognostic significance in predicting those tumors which have more aggressive behavior.

OBJECTIVE

To evaluate the expression of markers of cell proliferation (PCNA, Ki-67) and apoptosis (p53,Bcl-2) in patients with squamous cell carcinoma and actinic keratosis.

METHOD

We studied samples from 30 patients, ten patients of squamous cell carcinoma, ten with actinic keratosis and ten lesion-free samples from blepharoplasty.

RESULTS

p53 protein was expressed in all cases with different quantitative patterns. Bcl-2 was expressed at low intensity in six cases of actinic keratosis in the skin from blepharoplasty and negative in cases of squamous cell carcinoma. PCNA showed intense expression in all samples. Ki-67 showed variable expression in cases of keratosis and carcinoma and negative in the skin from the eyelid.

CONCLUSION

The high expression of Ki-67 associated with low expression of Bcl-2 indicates proliferation in the carcinoma group. Thus, expression of p53 and Bcl-2 in patients with actinic keratosis indicates cell immortalization.

c-erbB-2 and the "triple-state" in early breast carcinomas

Although c-erbB-2 expression is, in general terms, an ominous prognostic indicator in breast carcinomas, there are suggestions that lack of this oncogene, when combined with analogous lack of estrogen (ER negative) and progesterone receptors (PgR negative)-"triple-negative phenotype", is linked with an equally poor prognosis. We investigated this hypothesis in a series of early ductal breast carcinomas. A total of 116 specimens with early breast cancer, defined as tumors of < or =2 cm in size and clinically negative axilla, were studied immunohistochemically for ER, PgR, and c-erbB-2 expression. The median follow-up was 131 months (range 62-245 months). ER positive tumors had a favorable clinical course, compared to ER negative neoplasms, but only for the first 10 years of follow-up (P = 0.04). Prognosis was poorer for the PgR negative cases, relative to PgR positive tumors (P = 0.005), but this stood true for the entire investigation period. Triple-negative breast carcinomas had a poor prognosis, while triple-positive tumors had a favorable outcome. However, if triple-positive and triple-negative cases were excluded from the original sample, the remaining c-erbB-2 positive cases were connected with poor prognosis, relative to the remaining c-erbB-2 negative tumors. c-erbB-2 oncogene has a complex biological role in early breast carcinomas for its expression characterizes subgroups of patients with both favorable (triple-positive phenotype) and unfavorable prognosis (c-erb-B2 positive cases after excluding triple-positive and triple-negative tumors)-a phenomenon presumably due to activation of different biological pathways. Elucidation of these pathways may determine subgroups of patients with tumors requiring different targeted agents.

Association between DNA damage, DNA repair genes variability and clinical characteristics in breast cancer patients

The cell's susceptibility to DNA damage and its ability to repair this damage are important for cancer induction, promotion and progression. In the present work we determined the level of basal (total endogenous) and endogenous oxidative DNA damage as well as polymorphism of the DNA repair genes: RAD51 (135 G/C), XRCC3 (Thr241Met), OGG1 (Ser326Cys) and XPD (Lys751Gln) in peripheral blood lymphocytes of 41 breast cancer patients and 48 healthy individuals. DNA damage was evaluated by alkaline comet assay with DNA repair enzymes: Endo III and Fpg, preferentially recognizing oxidized DNA bases. The genotypes of the polymorphisms were determined by restriction fragment length polymorphism PCR. We observed a strong association between breast cancer occurrence and the genotypes C/C of the RAD51-135G/C polymorphism, Ser/Ser of the OGG1-Ser326Cys and Lys/Gln of the XPD-Lys751Gln, whereas the genotypes G/C of the RAD51-135G/C and Lys/Lys of the XPD-Lys751Gln exerted a protective effect against breast cancer. We also found that individuals with the G/C genotype of the RAD51-135G/C polymorphism and with the Lys/Lys genotype of the XPD-Lys751Gln polymorphism displayed a lower extent of basal and oxidative DNA damage. A strong association between higher level of oxidative DNA damage and the Lys/Gln genotype of the latter polymorphism was found. We also correlated genotypes with clinical characteristics of breast cancer patients. We observed a strong association between the G/C genotype of the RAD51-135 G/C polymorphism and the expression of the progesterone receptor and between both alleles of the OGG1-Ser326Cys polymorphism and lymph node metastasis. Our results suggest that the polymorphism of the RAD51, OGG1 and XPD genes may be linked with breast cancer by the modulation of the cellular response to oxidative stress and these polymorphisms may be considered as markers in breast cancer along with the genetic or/and environmental indicators of oxidative stress.

Association of low repair efficiency with high hormone receptors expression and SOD activity in breast cancer patients

OBJECTIVES

To evaluate the antioxidant status and repair capacity in breast cancer patients as well as the relationship between these parameters and expression of critical proteins in breast cancer tissue.

DESIGN AND METHODS

Blood samples were obtained from 25 female breast cancer patients and 19 healthy women. The antioxidant status was determined by the concentration of thiobarbituric-reactive substances (TBARS) and activity of superoxide dismutase (SOD) and catalase (CAT). The basal DNA damage and repair capacity in lymphocytes were evaluated by comet assay. The expression of p53, c-erbB2, Ki-67, estrogen receptor (ER) and progesterone receptor (PR) in cancer tissue was detected by immunohistochemical staining.

RESULTS

The breast cancer patients presented significantly elevated endogenous DNA damage in lymphocytes and lower susceptibility to DNA damage induced by H(2)O(2) when compared to the control group. There is a negative correlation between TBARS and sensitivity to peroxide induced DNA damage in patients. The percentage of residual damage after H(2)O(2) treatment followed by 3h of post-incubation is significantly higher in patients and also correlates positively with SOD activity, ER and PR expression and negatively with the basal DNA damage.

CONCLUSIONS

Our results demonstrate low repair capacity in lymphocytes of breast cancer patients and suggest that the regulation of DNA repair is sensitive to cellular redox state and can be modulated by ER/PR status.

Development of New Rabbit Monoclonal Antibody to Progesterone Receptor (Clone SP2)

Evaluation of estrogen and progesterone receptor (ER, PgR) status in breast cancer is widely used for the prediction of the response to endocrine therapy and as a biologic parameter closely related to disease prognosis. The IHC method is considered to be a specific, sensitive, and economical method for determining ER and PgR status. The authors developed the first rabbit anti-PgR mAb (clone SP2) used in IHC on formalin-fixed, paraffin-embedded tissue sections from breast carcinomas. This new antibody, compared with currently available anti-PgR antibodies, has important advantages, including its reactivity even without heat-based antigen retrieval of fixed-embedded tissue sections in IHC and the predominance of nuclear immunostaining with only very low cytoplasmic signal. A comparative study of IHC on 107 histologic specimens from breast cancer cases showed that SP2 yields the same results as the wellknown mouse mAb to PgR (clone 1A6). The antibody affinity of SP2 is 12 times higher than that of 1A6. Thus, SP2 may prove of great value in the assessment of PgR status in human breast cancer.

Prognostic Significance of Estrogen Receptor Beta in Epithelial Hyperplasia of Usual Type With Known Outcome

The prognostic significance of ER-alpha expression in benign proliferative breast disease has been confirmed in epithelial hyperplasia of usual type (HUT). However, little is known about the role of ER-beta in these lesions. Therefore, this study was performed to test the hypothesis that, in HUT lesions, the ratio of ER-alpha:ER-beta is an accurate determinant of breast cancer risk and of predicting subsequent progression to invasive breast cancer. This case-control study analyzed a cohort of benign proliferative breast lesions and foci of ductal HUT in 117 patients with long follow-up (20 years). These foci were analyzed by morphometric image analysis together with immunohistochemistry using monoclonal antibodies to ER-beta1 and to ER-alpha. The data were compared with ER-beta expression in all breast carcinomas that subsequently developed in the same patients as well as to ER-alpha expression in the corresponding tissues. In cases that progressed to carcinoma, the ratio of ER-alpha to ER-beta in HUT was significantly higher (P < 0.001) than in those that did not progress. None of the HUT foci from patients who progressed to breast cancer were simultaneously ER-alpha negative and ER-beta positive. Using both ER-beta and ER-alpha in a logistic model demonstrated a 75% correct classification rate for the cohort studied. These findings confirm the diagnostic and prognostic value of defining the ER-alpha and ER-beta status of HUT lesions identified morphologically. The data support the hypothesis that high ER-alpha:ER-beta levels characterize those cases within HUT likely to progress to breast cancer. The data also reveal that a reduced level of ER-beta relative to ER-alpha is an accurate predictor of individual cases of HUT likely to progress to invasive breast carcinoma, thus supporting the concept that ER-alpha transcriptional activity is directly modulated by ER-beta.

Development of New Rabbit Monoclonal Antibody to Estrogen Receptor

Evaluation of estrogen and progesterone receptors in breast cancer is widely used for the prediction of the response to endocrine therapy and as a biologic parameter closely related to disease prognosis. Immunohistochemistry is considered a specific, sensitive, and economic method for the determination of estrogen receptor/progesterone receptor status. The authors developed the first rabbit antiestrogen receptor monoclonal antibody (clone SP1) used in immunohistochemistry on formalin-fixed, paraffin-embedded tissue sections especially from breast carcinomas. This new antibody, compared with currently available antiestrogen receptor antibodies, has important advantages, including its reactivity even without heat-based antigen retrieval of fixed, embedded tissue sections in immunohistochemistry, and the predominance of nuclear immunostaining with only a very low cytoplasmic signal. A comparative study of immunohistochemistry on 61 histologic specimens from breast cancer cases showed that SP1 yields the same results as the well-known, standardized mouse monoclonal antibody to estrogen receptor (clone 1D5). Antibody affinity of SP1 is 8 times higher than that of 1D5. Thus, SP1 may prove of great value in the assessment of estrogen receptor status in human breast cancer.

Wild-type oestrogen receptor beta (ERbeta1) mRNA and protein expression in Tamoxifen-treated post-menopausal breast cancers

This study has tested the hypothesis that comparison of protein and mRNA expression for ERα and ERβ1 by human breast cancers provides novel information relating to the clinical and pathological characteristics of human breast cancers. Expression of ERα and ERβ1 was identified in 167 invasive cancers from postmenopausal women treated only with endocrine therapy. The cohort included 143 cases receiving only adjuvant Tamoxifen following surgery. ERα and ERβ1 expression was analysed by immunohistochemistry and reverse transcription RT–PCR and compared with clinical progression of individual cancers. ERα protein was closely associated with the corresponding RNA detected by RT–PCR (Chi-square, P<0.001). In contrast, ERβ1 protein and mRNA were inconsistent. Although an association was identified between ERα and ERβ mRNAs (Chi-square, P<0.001) and between ERα protein and ERβ1 mRNA (Chi-square, P<0.027), no association was identified for the ERα and ERβ1 proteins detected by immunohistochemistry. ERβ1 was not associated with outcome. However, in the absence of ERα, ERβ1 protein expression was associated with elevated cell proliferation. There was a trend for the ERβ1 protein-positive cases to have a worse outcome, both within the group as a whole as well as within the ERα-positive Tamoxifen-treated cases. This study has confirmed the hypothesis that expression of ERα is an important determinant of breast cancer progression, and has further demonstrated that ERβ1 may play a role in the response of breast cancers to endocrine therapy.

Comparison of Immunoexpression of 2 Antibodies for Estrogen Receptors (1D5 and 6F11) in Breast Carcinomas Using Different Antigen Retrieval and Detection Methods

The importance of in situ immunodetection of hormone receptors for therapy planning and prognostic evaluation in patients with breast carcinoma is well established. Sensitive detection methods are of utmost importance, especially in poorly fixed tissues, which are not uncommon in routine pathologic practice. The purpose of the present study is to compare immunoexpression of estrogen receptors in 20 cases of invasive ductal carcinoma using two antibodies, 1D5 and 6F11, and to verify the effect of different antigen retrieval solutions and detection systems. Immunoperoxidase was performed on paraffin sections using 1D5 and 6F11 as primary antibodies. Heat-induced antigen retrieval was performed using citrate buffer (pH 6.0) or Tris-EDTA buffer (pH 8.9). Detection was achieved using the following systems: EnVision, EnVision Plus, and labeled streptavidin-biotin peroxidase complex. Reaction was semiquantified from 0 to 4. There were no differences between the two markers, 1D5 and 6F11, except when 6F11 was used with EnVision and citrate buffer, in which case weaker reactivity was observed. Only in this combination (6F11/EnVision) was EDTA buffer significantly better than citrate. Labeled streptavidin-biotin peroxidase complex presented the best results, followed by EnVision Plus.

A three-dimensional organotypic culture of the human uterine exocervix for studying mucosal epithelial differentiation and migrating leukocytes

We report on a three-dimensional organotypic culture in vitro of explants from the human uterine exocervix. Exocervical fragments (2-3 mm3) from pre-menopausal women were cultured on sponges submerged in Dulbecco's Modified Eagle's Medium containing p-nonylphenol and 10% fetal bovine serum for up to 3 weeks and the viability and cellular responses were assayed. The fragments were analyzed by immunohistochemistry for the expression and distribution of a broad spectrum of cellular markers: p63, Ki-67, involucrin, high molecular weight cytokeratins, estrogen receptor-alpha, vimentin, CD45, and CD31. The fragments preserved their tissue architecture and cellular heterogeneity comparable to that observed in exocervical tissue in vivo. Prior to culture, the original epithelium was composed of stratified multilayered keratinocytes with integrated monocyte/dendritic-like cells in the basal and suprabasal layers. The epithelium began to exfoliate in culture and within 4 days appeared to have lost its differentiated high-zone layers of keratinocytes. After 10 days a new epithelium, slightly different from the original one, was formed; it displayed an increasing prominence of basal and suprabasal keratinocyte layers, containing infiltrating leukocytes that had probably migrated from the submucosa. The epithelium subsequently lost its organization, concomitant with a progressive involution of the stroma. Subepithelial capillaries appeared to be well maintained throughout the culture period. Aside from the maintenance of cellular heterogeneity within the fragments of exocervix, these culture systems are a valuable tool for studying the mechanisms of epithelial regeneration, and may prove to be a useful model for studying mucosal immunity.

Optimal fixation conditions for immunocytochemical analysis of estrogen receptor in cytologic specimens of breast carcinoma

BACKGROUND

The techniques for immunostaining estrogen receptor (ER) in cytologic specimens have varied, as have the detection rates. The authors compared various fixation methods for their effect on ER detection in cytologic smears of breast carcinoma.

METHODS

Smears were prepared by gently scraping the cut surfaces of 47 resected breast carcinoma specimens and placing immediately in 1 of the following conditions: 1) a sequence of 10% formalin-methanol-acetone fixatives at -20 degrees C (Abbott method); 2) 10% formalin at room temperature; and 3) Carnoy's fixative at room temperature and then Papanicolaou stained (Carnoy's-Pap). Destaining of Carnoy's-Pap smears (Carnoy's-dPap) was initially attempted before ER staining. One set of smears was also air-dried for 3 minutes before using the Abbott method. Smears and corresponding tissue sections were immunostained with anti-ER antibody 6F11 using a similar protocol except for antigen retrieval, which was not initially applied on cytologic slides. All the ER-negative smears that had been fixed with 10% formalin or Carnoy's-Pap were restained after antigen retrieval. Agreement between cytologic and histologic findings was expressed by both concordance and the kappa coefficient.

RESULTS

ER detection in smears processed with the Abbott method correlated best with findings from tissue samples, with an overall correlation of 91.5% (kappa = 0.80). Findings from air-dried smears were less optimal (concordance, 84.4%; kappa = 0.65), followed by Carnoy's-Pap (concordance, 71.4%; kappa = 0.45), formalin (concordance, 31%; kappa = 0.05), and Carnoy's-dPap (concordance, 29.4%; kappa = 0.04). Antigen retrieval converted most of the ER-negative smears to positive (18 of 20 smears in formalin and 6 of 8 smears in Carnoy's-Pap), leading to a final concordance of 93% and kappa = 0.83 for both conditions. Antigen retrieval also led to stronger staining intensity without causing false positivity.

CONCLUSIONS

Antigen retrieval was found to greatly improve ER immunodetectability and staining intensity in formalin-fixed and Carnoy's-Pap smears. The former may offer an alternative to the Abbott method because of its easiness and the latter can be reliably used in archival Pap-stained smears for retrospective analysis of ER. Air-drying, destaining Pap smear, and fixation in formalin or Carnoy's-Pap without antigen retrieval are not recommended.

Increased risk of malignant progression in benign proliferating breast lesions defined by expression of heat shock protein 27

Heat shock protein 27 (hsp-27) is a regulator of oestrogen receptor (ER) expression and a modulator of intracellular homeostasis. In this laboratory, Shaaban et al demonstrated the importance of ER-α, together with Ki67, in enhancing the progression of benign breast lesions of defined morphological types. To better understand the mechanisms by which ER-α promotes breast neoplasia, this study was performed to test the hypothesis that the roles of ER-α and hsp-27 may be defined by their quantitative expression in proliferative breast lesions of varying histological risk. The expression of hsp-27 was identified using a specific monoclonal antibody and analysed to assess the proportion of positive epithelial cells using digitised morphometric image analysis. The expression of ER-α was analysed by immunohistochemistry and Western blotting in a variety of benign (HUMA121) and malignant mammary cell lines, including ER-α(+) (MCF7, ZR-75, T47D) and ER-α(−) (MDA-MB 231) breast cancer cell lines. The data confirm that, during progression from normal through proliferative breast lesions to in situ cancer, there was a significant increase in both the proportion and the optical density of the epithelial cells expressing hsp-27. The mean levels of expression ranged from 7.4% of the total number of epithelial cells in normal lobules to 25.17% of epithelial cells in hyperplasias of usual type (HUT) to 61.1% of epithelial cells in ductal carcinoma in situ (P<0.001). The study has confirmed the expression of hsp-27 to be closely associated with ER-α(+) expression, and that its regulated expression occurs early along the mammary oncogenic pathway, supporting the initial hypothesis. It is our proposal that the differential expression of hsp-27 modulates the phenotypic behaviour of morphologically benign epithelial cells and hence may be an important determinant in initiating, or promoting, a population of human mammary cancers.

Declining estrogen receptor-beta expression defines malignant progression of human breast neoplasia

It has been shown that the risk of breast cancer developing in certain morphologically identifiable benign breast lesions correlates with expression of estrogen receptor alpha (ER-alpha). Although ER-alpha and ER-beta genes share a large degree of homology, it is generally thought that their distribution and functions are substantially different in many tissues. Recent development of reliable antibodies to ER-beta has provided this first opportunity to test the hypothesis that the likelihood of malignant transformation in morphologically benign breast lesions can be accurately defined by the distribution and level of ER-beta expression relative to that of ER-alpha. Using a monoclonal antibody, ER-beta protein expression has been analyzed in 53 normal breasts and compared with a cohort of histologically distinct breast lesions of different prognostic risk (54 hyperplasia of usual type, 35 ductal carcinoma in situ, and 141 invasive cancers). All of these tissues were also assessed for ER-alpha. Expression of ER-beta protein was also analyzed in an additional spectrum of benign breast lesions with low or negligible risk of progression to malignancy. The median proportion of cells expressing ER-beta was highest in normal breast lobules (median 94.33%, interquartile range 78.25-99.00) but declined significantly through usual ductal hyperplasia (median 76.67, interquartile range 49.17-95.00, P = 0.002) and ductal carcinoma in situ (median 70.00, interquartile range 59.00-85.00, P = 0.009) to invasive cancer (median 60.00, interquartile range 50.00-80.00, P < 0.001). An appreciable proportion (33.81%) of ER-alpha-negative invasive cancers expressed ER-beta. A high but variable level of ER-beta expression occurred in the benign lesions. The data from the intact histologic tissues were evaluated with respect to the relative expression of ER-alpha and ER-beta in five mammary cell lines of different behavioral phenotype (MCF7, ZR-75, T47D, MDAMB231, HUMA121). The highly significant differences in expression and distinct tissue distributions of ER-alpha and ER-beta within the histologic lesions of defined risk, together with the data from the cell lines, support the original hypothesis that the tissue concentration, relative occurrence, and/or interaction of these two types of estrogen receptor may play an important role in modulating mammary tumorigenesis.

Aberrant P-cadherin expression: is it associated with estrogen-independent growth in breast cancer?

Breast carcinomas represent a heterogeneous group of tumors, with a diverse biologic behavior, outcome, and response to therapy. Recent studies have demonstrated that alterations in the expression of adhesion molecules in cancer cells are related to aggressiveness and poor prognosis. The aim of our study was to investigate the expression of P-cadherin in breast carcinomas and correlate it with estrogen receptor (ER) status. We selected 73 ductal carcinomas in situ (DCIS) and 149 invasive carcinomas of the breast, and assessed the expression of P-cadherin as well as other biologic markers. P-cadherin expression showed a strong inverse correlation with ER expression in both types of breast carcinoma (in situ and invasive). P-cadherin-positive and ER-negative tumors were related to a higher histologic grade, a high proliferation rate, and expression of c-erbB-2. We demonstrated that P-cadherin identifies a subgroup of breast carcinomas that lacks ER expression, and correlates with higher proliferation rates and other predictors of aggressive behavior. We believe that these tumors represent an advanced step in cancer progression, and our data support the hypothesis that an estrogen-independent pathway regulates P-cadherin expression.

Oestrogen receptor negativity as a marker for high-grade ductal carcinoma in situ of the breast

AIMS

To compare the morphological and immunohistochemical characteristics of oestrogen receptor (ER)-negative and ER-positive ductal carcinoma in situ (DCIS) of the breast, in an attempt to establish more objective criteria for the classification of DCIS.

METHODS AND RESULTS

Sections of 64 cases of in-situ carcinoma of the breast were stained for ER, progesterone receptors (PgR), androgen receptors (AR), c-erbB-2 and p53, using the immunoperoxidase technique. The cases included 60 DCIS and four lobular carcinoma in situ (LCIS). Four DCIS lesions were associated with foci of microinvasion. The 60 DCIS cases included 31 high grade, 23 intermediate grade and six low grade. Twenty-four DCIS cases (40%) were ER-negative and 36 were positive. ER negativity was significantly associated with high nuclear grade (88% versus 27% for ER-positive cases, P < 0.001), PgR negativity (100% versus 25%, P < 0.001), c-erbB-2 positivity (79% versus 14%, P < 0.001) and p53 positivity (58% versus 6%, P < 0.001). There was no difference between ER-negative and -positive DCIS as regards AR expression, with 91% of cases in each group being AR-positive. Of the four cases of DCIS with microinvasion, three were ER- and PgR-negative, all four were c-erbB-2-positive and AR-positive and one was p53-positive. None of the four LCIS was ER, PgR or AR-negative and none was c-erbB-2- or p53-positive.

CONCLUSIONS

There is a highly significant direct relationship between ER negativity in DCIS and high nuclear grade, PgR negativity and c-erbB-2 and p53 positivity. We suggest that immunohistological assessment of ER status may help in providing a more objective way of classifying DCIS.

Evaluation of seven oestrogen receptor beta antibodies for immunohistochemistry, western blotting, and flow cytometry in human breast tissue

Two oestrogen receptors, ER alpha and ER beta, exist. While much is known about ER alpha, the role of ER beta is still undefined, especially at the protein level. The aim of this study was to determine the utility of seven ER beta antibodies (14C8, 8D5, PAI313, PPG5/10, N19, 9.88, and D7N) raised against different domains of ER beta in three commonly used laboratory applications, namely immunohistochemistry, western blot, and flow cytometry, using human breast material. For immunohistochemical analysis of frozen material, PAI313 and D7N gave stronger and more specific signals than 14C8, 8D5, and PPG5/10. In paraffin sections, 14C8, closely followed by PPG5/10, gave by far the most superior nuclear immunoreactivity, compared with the other antibodies tested. In general, flow cytometry results mirrored the immunohistochemistry data for paraffin sections, with antibodies ranked 14C8 > 8D5> or = PAI-313 > PPG5/10 >D7N. For western blotting, 8D5 and D7N yielded the strongest and most consistent bands, with weaker bands seen with the others. It is concluded that ER beta protein can be detected using specific antibodies. However, there is considerable variation between the specificity and application of these antibodies, highlighting the fact that careful optimization is required when selecting an antibody for use in a particular laboratory technique.

Morphologic spectrum of estrogen receptor-negative breast carcinoma

CONTEXT

Estrogen receptor (ER)-negative breast carcinomas are a heterogeneous group of breast cancers that are generally thought to be aggressive.

OBJECTIVE

To determine the morphologic and immunohistochemical spectrum of a consecutive series of ER-negative breast carcinomas, in an attempt to understand the pathogenesis and behavior of these lesions.

DESIGN

Seventy-four consecutive cases of ER-negative invasive carcinomas were studied. Hematoxylin-eosin-stained sections were reviewed, and new sections were stained for c-erbB-2, p53, vimentin, and androgen and prolactin receptors. The findings were correlated with the axillary lymph node status as a measure of tumor aggressiveness.

SETTING

The histopathology department of a tertiary referral teaching hospital.

RESULTS

The tumors included 50 (68%) invasive ductal carcinomas, 21 (28%) medullary/atypical medullary carcinomas, and 1 each of invasive lobular, apocrine, and papillary carcinoma. Some of the invasive ductal cases had distinctive features that are described in this report. Maximum tumor diameter varied between 5 and 100 mm. Sixty tumors (81%) were grade 3, 13 (18%) were grade 2, and 1 (1%) was grade 1. Of the 60 cases in which the axillary node status was known, 34 (57%) had metastases, and 26 did not. Tumors associated with positive nodes were significantly larger than those associated with negative nodes (37.2 vs 17.8 mm, P <.001). A higher percentage of node-negative tumors were c-erbB-2 positive (42% vs 21%, P <.05). There were no differences between the 2 groups with regard to histologic type, tumor grade, or the expression of p53, vimentin, or androgen or prolactin receptors.

CONCLUSIONS

Many ER-negative breast carcinomas have distinctive microscopic features. Not all ER-negative tumors are aggressive, as judged by the absence of lymph node metastases in 43% of cases in this series. Tumor size is the most important indicator for the likelihood of the presence of lymph node metastases. The wide range of tumor sizes encountered in this series suggests that the ER status of a tumor is determined early in its natural history and supports the existence of 2 separate pathways for the development of ER-negative and ER-positive breast carcinomas.

Breast cancer risk in usual ductal hyperplasia is defined by estrogen receptor-alpha and Ki-67 expression

The hypothetical multistep model for breast carcinogenesis indicates that invasive carcinoma arises via a series of intermediate hyperplastic lesions through various grades of atypia to in situ and invasive carcinoma. Non-atypical hyperplasia [hyperplasia of usual type (HUT)] is a nonobligate precursor of breast cancer. Although its further morphological subclassification is unlikely, refining is more likely to depend on defining biological markers of risk. Having assembled a cohort of benign proliferative breast lesions of known outcome, we studied the expression of estrogen receptor-alpha (ER-alpha) and Ki-67 using morphometric image analysis as well as dual-labeled immunofluorescence in HUT foci and in surrounding normal lobules of 25 patients that progressed to breast cancer and 19 controls. Those patients that progressed to breast cancer (cases) showed significantly higher ER-alpha [median, 57.00% of cells within individual HUT foci; interquartile range (IQ), 33.48 to 67.78] and Ki-67 (median, 3.82%; IQ, 0.85 to 11.28) expression in their HUT foci compared with controls (ER-alpha median, 30.27%; IQ, 19.75 to 52.50 and Ki-67 median, 0.77%; IQ, 0.0458 to 1.72, P = 0.008 and <0.001). No significant difference in expression of dual-stained cells was found between cases and controls. Although normal lobules from cases showed higher ER-alpha expression compared with controls, this was not statistically significant. Our data point to a previously undescribed hormone-dependent pathway in this particular group of breast neoplasms and suggest the possibility of selective hormonal therapy to suppress the proliferative potential of these benign but high-risk breast lesions. The findings of this study might have important implications for improving breast cancer screening and management strategies.

Steroid hormone receptors in parotid gland cystadenolymphoma (Warthin's tumour)

The aetiopathogenesis of cystadenolymphoma is mostly unknown. Cystadenolymphomas have a significantly higher incidence in the male than the female population. This might be as a result of endocrine dependency in this kind of tumour. The purpose of the present study was to determine the sex hormone receptor status in cystadenolymphoma. Tissue samples of cystadenolymphoma, pleomorphic adenoma and normal samples of the parotid gland were examined immunohistochemically for oestrogen and progesterone receptors. Progesterone-positive cells could be found in the salivary duct system of normal glands and in the epithelial components of cystadenolymphomas. There was no evidence for the presence of oestrogen receptor in any sample studied. The evidence of progesterone receptors in cystadenolymphoma may implicate a potential role of endocrine factors in the development of this tumour.

Estrogen receptor status in primary breast cancer: iodine 123-labeled cis-11beta-methoxy-17alpha-iodovinyl estradiol scintigraphy

PURPOSE

To determine the sensitivity of iodine 123 ((123)I)-labeled cis-11beta-methoxy-17alpha-iodovinyl estradiol (Z-MIVE) scintigraphy for the detection of estrogen receptors in patients with primary breast carcinoma.

MATERIALS AND METHODS

In 22 patients, estrogen receptor status was assessed with planar scintigraphy and single photon emission computed tomography (SPECT) 4 hours after the injection of 185 MBq (123)I-labeled Z-MIVE. For histologic and estrogen receptor immunohistochemical analysis, breast carcinoma tissue was obtained in all patients by means of biopsy or resection of the primary tumor. Two experienced physicians semiquantitatively scored the scintigraphic and immunohistochemical findings. The uptake ratio at scintigraphy and the immunohistologic staining intensity were scored as negative, weak, intermediate, or strong.

RESULTS

All patients had histologically proven breast cancer. Immunohistologic staining for estrogen receptors yielded negative findings in four patients and positive findings in 18 (weak staining, n = 2; intermediate staining, n = 6; strong staining, n = 10). Planar (123)I-labeled Z-MIVE scintigraphic findings were negative in five patients and positive in 17 (weak uptake, n = 2; intermediate uptake, n = 10; strong uptake, n = 5), resulting in one false-negative finding. Findings at (123)I-labeled Z-MIVE SPECT were negative in four patients and positive in 18. The sensitivities of (123)I-labeled Z-MIVE scintigraphy for estrogen receptors were 100% with SPECT and 94% with planar scintigraphy. The correlation between immunohistologic and planar scintigraphic scores of estrogen receptor status was 0.72 (P <.01).

CONCLUSION

(123)I-labeled Z-MIVE scintigraphy is a sensitive noninvasive tool for the detection of estrogen receptors in patients with breast cancer.

Comparative tissue distribution of the processing enzymes "prohormone thiol protease," and prohormone convertases 1 and 2, in human PTHrP-producing cell lines and mammalian neuroendocrine tissues

Peptide hormones are generated by proteolytic processing of their respective protein precursors by several prohormone processing proteases. The peptide hormone PTHrP is widely expressed in normal and malignant tissues, where proPTHrP undergoes proteolytic processing to generate PTHrP peptides with distinct biological actions. In this study, the tissue distribution of the prohormone processing enzymes PTP, PC1, and PC2 were compared by immunohistochemistry in human PTHrP-producing cancer cell lines, and in mammalian neuroendocrine and other tissues from rat and bovine that contain peptide hormones. PTP, PC1, and PC2 were prominently expressed in PTHrP-expressing human cancer cell lines originating from tumors of the breast, lung, prostate, as well as lymphoma. These processing enzymes also showed significant expression in normal mammalian neuroendocrine tissues from bovine and rat, including pituitary, hypothalamus, adrenal medulla, pancreas, and other tissues. Most neuroendocrine tissues contained prominent levels of at least two of the three processing enzymes examined, and all tissues contained at least one of these three enzymes. Differential expression of processing enzyme proteins was also demonstrated by Western blots. The differential expression of PTP, PC1, and PC2 observed in certain cancer and normal neuroendocrine cell types postulates selective roles for these processing enzymes in different tissues for generating biologically active peptide hormones. These results support the importance of these processing enzymes in their hypothesized roles in prohormone processing.

Comparison of five different antibodies in the immunohistochemical assay of estrogen receptor alpha in human breast cancer

BACKGROUND

Estrogen receptor alpha (ER) expression is the best prognostic and predictive factor of hormone dependency of human breast cancers. Unlike enzyme immunoassay (EIA), which has been widely used to evaluate ER status in breast cancer, immunohistochemical assay (IHC) can detect ER in a small amounts of tissue with detailed localization. Although there is a sufficient number of ER antibodies against various regions of the protein, the reliability of IHC staining is only well understood for a few. IHC and EIA for the evaluation of the ER status of human breast cancer, therefore, should be compared using the same breast cancer tissues.

METHODS

Five different ER antibodies (1D-5, C-314, G-20, C-311 and HC-20) that identify different amino acid sequences were used. The evaluation of ER status by IHC using these antibodies was compared with EIA concomitantly in 97 primary human breast cancer tissues

RESULTS

The positivity rate for EIA was 68%. That of IHC for antibodies 1D-5, C-314, G-20, C-311 and HC-20 was 50.5%, 47.4%, 46.4%, 44.3% and 57.7%, respectively. The concordance between EIA was 76.3% for 1D-5 and 77.3% for HC-20, which is statistically highly significant (p<0.0001); Other antibodies were not.

CONCLUSIONS

HC-20 is most suitable in the evaluation of the ER status of human breast cancers using the IHC method. Although antibody 1D-5 is also available, C-314, G20 and C-311 are unreliable in such an evaluation.

Expression of TGF-alpha and EGFR in Breast Cancer and its Relation to Angiogenesis

Immunohistochemical analysis of the expression of transforming growth factor alpha (TGF-alpha) and its receptor, epidermal growth factor receptor (EGFR), was performed in a series of 86 invasive carcinomas of the breast. TGF-alpha immunostaining was observed in the majority of the cases (72.1%), both in epithelial cells and in adjacent stromal cells. EGFR was also present in tumors (34.2%) and in the endothelial cells (46.1% of the cases) near the tumors. A significant association was observed between TGF-alpha expression and angiogenesis evaluated by immunohistochemistry using an antibody against factor VIII-related antigen. No association was observed between TGF-alpha expression and other clinicopathologic features. In contrast, EGFR expression in the tumor was associated with features of poor prognosis, such as tumor size, histologic grade, lymph node status, estrogen receptor content, p53 expression, sialyl-Tn expression, and age. The presence of EGFR in endothelial cells was correlated to young patient age. We also observed an association of EGFR in endothelial cells and angiogenesis in tumors with a size of less than 2 cm. Inversely, in larger tumors, angiogenesis was only associated with tumor TGF-alpha expression. These results indicate that endothelial EGFR may play a role in the early steps of breast cancer angiogenesis.

A novel flow cytometric steroid hormone receptor assay for paraffin-embedded breast carcinomas: an objective quantification of the steroid hormone receptors and direct correlation to ploidy status and proliferative capacity in a single-tube assay

Semiquantitative estimation of steroid hormone receptors by immunohistochemistry applied to paraffin sections is common practice in surgical pathology. Flow cytometric (FCM) analysis of estrogen receptor (ER) and progesterone receptor (PR) levels provides a faster and more objective quantitative assay. However, a major problem in such FCM analyses of solid tumor samples is the admixture of tumor cells with normal epithelial, stromal, and inflammatory cells. The aim of the underlying study was to investigate the applicability of a recently developed multiparameter flow cytometric methodology for the accurate estimation of the fraction of steroid hormone receptor-positive tumor cells and to explore whether this multiparameter approach allows the detection of specific, clinically relevant subsets of tumors, based on a combination of ploidy level, steroid hormone receptor status, and cell cycle characteristics. For this purpose, samples of 42 breast cancer patients, from which routine immunohistochemistry for ER and PR also was available, were analyzed. From each case, a cell suspension was prepared from the paraffin block by applying a heating and short pepsin digestion step to 50-microm-thick sections. These cell suspensions were double-immunostained for cytokeratin to identify the epithelial cells, and ER or PR, whereas DNA was quantitatively stained with propidium iodide using an optimized protocol. In the entire group of breast tumors, the percentages of ER- and PR-positive cells were registered in the epithelial subfraction, in combination with DNA ploidy and S phase fraction (SPF). A significant correlation was found between the fraction of hormone receptor-positive cells as found by the immunohistochemical and FCM procedures. For ER, a correlation coefficient of r = .87 was found, and for PR r = .62, both P < .0001. It became clear that all the diploid breast tumors had more than 30% tumor cells positive for ER with a SPF lower than 10%, whereas aneuploid tumors contained on average a smaller percentage of steroid hormone receptor-positive cells, and simultaneously an SPF greater than 10%. Our results show that this multiparameter FCM analysis allows an objective and reproducible quantification of the fraction of steroid hormone receptor-positive cells in the relevant epithelial cell compartment in relation to DNA ploidy status and proliferative capacity in a single-tube assay.

Prognostic significance of oestrogen receptor beta in breast cancer

BACKGROUND

Endocrine therapy for breast cancer is now well established and with the identification of a second oestrogen receptor, ERbeta, 3 years ago it is timely to review the possible significance of this receptor in breast cancer management.

METHODS

An up-to-date review of the current literature concerning the role and possible implications of ERbeta in human breast cancer was undertaken.

RESULTS

Wild-type and variant ERbeta are expressed in human breast tumours. Expression of ERbeta correlates with accepted prognostic indicators including lymph node status and tumour grade. Furthermore, levels of ERbeta messenger RNA alter during carcinogenesis and are upregulated in breast tumours that develop antioestrogen resistance.

CONCLUSION

ERbeta has potential as a novel clinical prognostic marker in breast cancer, particularly in determining tumours that are resistant to tamoxifen.

P53 in breast carcinomas: association between presence of mutation and immunohistochemical expression using a semiquantitative approach

The aim of this study was to evaluate the concordance between the presence of p53 mutations in breast carcinomas expressing the protein by immunohistochemistry. A series of 60 breast carcinomas was evaluated by immunohistochemistry using monoclonal antibodies against p53 protein (DO 7 and PAb 1801). Twenty cases classified as being positive for p53 according to the current approach (if 5% or more of neoplastic cells contained reaction product in the nucleus) were used for molecular studies. These cases were re-assessed semi-quantitatively using a scoring system based on intensity and percentage of stained cells. DNA was phenol-chloroform extracted from microdissected normal and tumour cells obtained from formalin-fixed, paraffin-embedded tissue sections. Mutations in the p53 gene were analysed by SSCP (single strand conformational polymorphism) with primers covering exons 2-3 to 11. Ten out of the 20 p53-positive cases presented mutations detected by SSCP analysis. Mutations have been found in several exons ranging from exon 4 to exon 10. We observed a positive relationship between the presence of mutations and immunohistochemical evaluation of p53 protein expression using a semiquantitative scoring system. All cases with more than 2/3 stained tumour cells and strong intensity of staining exhibited p53 mutations. At variance, no p53 mutations were found in cases with less than 1/3 stained tumour cells and moderate intensity of staining. Therefore, only the identification of positivity for p53 detected by immunohistochemistry did not always reflect the detection of p53 mutations in breast cancer, however the use of a semi-quantitative approach seems to be useful as an indicator of the presence of mutation.

Breast carcinoma developing in patients on hormone replacement therapy: a histological and immunohistological study

AIM

To study the histopathological features of breast carcinoma developing in postmenopausal patients on hormone replacement therapy (HRT).

METHODS

The sample comprised 60 patients with invasive breast carcinoma including 31 who had received HRT at or shortly before presentation, and 29 who had not. Details concerning their tumour size, histological type and grade, lymph node status, and oestrogen and progesterone receptor status were compared. Immunoperoxidase staining for Bcl-2, p53, and E-cadherin was carried out on paraffin sections of all 60 patients. The results were then statistically analysed.

RESULTS

Tumours detected in HRT patients were significantly smaller (mean 17 mm v 25 mm; p = 0.0156) and of a lower histological grade (p = 0.0414) than those detected in non-HRT patients. The incidence of invasive lobular carcinoma was slightly higher in HRT patients (19% v 14%). Immunohistologically, 87% of HRT tumours were Bcl-2 positive (compared with 79% in the control group), 29% were p53 positive (45% in the control), and 48% were E-cadherin positive (72% in the control group). Although the differences were not statistically significant there was a trend towards higher incidence of p53 negative and E-cadherin negative tumours in HRT patients.

CONCLUSIONS

Breast carcinomas detected in patients on HRT have a significantly higher incidence of two favourable prognostic features (small size and a low histological grade). They also show a trend, statistically not significant, of being p53 negative and E-cadherin negative; this may be related to the slightly higher incidence of invasive lobular tumours in these patients.

Short-term primary culture of epithelial cells derived from human breast tumours

As experimental models for breast cancer, most studies rely on established human breast cancer cell lines. However, many of these lines were established over 20 years ago, many from pleural effusions rather than the primary tumour, so the validity of using them as representative models is questionable. This paper describes our experiences, over a 3-year period, in establishing short-term epithelial-cell-enriched preparations from primary breast tumours based on differential centrifugation followed by culture in selective media. Epithelial cells were successfully cultured from 55% of samples, but culture success did not appear to be correlated with tumour histology, stage, grade or node status. Epithelial cell-enriched cultures were immunopositive for broad-spectrum cytokeratin and epithelial membrane antigen (EMA). Positivity for keratin 19 confirmed that the cultures contained tumour-derived cells, which additionally showed significantly higher activity of the reductive pathway of the steroid-converting enzyme 17beta-hydroxysteroid dehydrogenase type I. That the cultures contained tumour and not normal epithelial cells was further substantiated by the complete absence of the calmodulin-like gene NB-1 in tumour-derived cultures; this is only associated with normal breast epithelia. Eighty-five per cent of cultures established from oestrogen receptor (ER)-positive tumours expressed ER in vitro; this was functional in 66% of cultures, although ER-positive phenotype was gradually lost over time. In conclusion, epithelial cells can be isolated and maintained as short-term cultures from primary breast tumours irrespective of histopathological or clinical details, providing a model system with a greater biological and clinical relevance than breast cancer cell lines.

Correlation between the growth of uterine leiomyomata and estrogen and progesterone receptor content in needle biopsy specimens

OBJECTIVE

To examine the relationship between estrogen receptor (ER) and progesterone receptor (PR) content in needle biopsy specimens and the growth of uterine leiomyomata after biopsy.

DESIGN

Prospective clinical study.

SETTING

University teaching hospital.

PATIENT(S)

Thirty-one women with uterine leiomyomata and a normal menstrual cycle.

INTERVENTION(S)

Transcervical needle biopsy of uterine leiomyomata.

MAIN OUTCOME MEASURE(S)

The relationships between histologic features (smooth muscle content, immunohistochemical expression of ER and PR) and the percent increase over a 12-month observation period in the volume of the largest myoma nodule measured by magnetic resonance imaging were analyzed.

RESULT(S)

Both the density and intensity of immunohistochemical staining of PRs in uterine leiomyoma tissue showed significant positive correlation with leiomyoma growth.

CONCLUSION(S)

The growth of uterine leiomyomata can be determined by histologic and immunohistochemical analysis of needle biopsy specimens from uterine leiomyomata.

Clinicopathologic features and incidence of invasive lobular carcinoma in Japanese women

Intending to clarify the true incidence of invasive lobular carcinoma of the breast in Japanese women as well as the frequency of unilateral multicentricity, 362 cases of clinically defined monocentric breast cancer without pre-operative biopsy (previously fine needle aspiration or needle biopsy were routinely carried out for every case) were examined by whole mammary gland serial sectioning. On the basis of pathology and the World Health Organization classification of breast tumors, each case was assigned to one of two main histologic types: invasive lobular carcinoma (ILC) or invasive ductal carcinoma (IDC). Invasive lobular carcinoma was further separated into classic and variant types by employing previously published criteria. Twenty-one cases of ILC (5.8%) were diagnosed, which is more than in most previous Japanese studies. Unilateral multicentric breast carcinoma was detected in 9.5% of ILC and 16.1% of IDC (the difference was found not significant). Microscopically, ILC tumors were found to be, on average, larger than IDC. Patients with classic type ILC tended to be younger than those with variant type or IDC. Estrogen receptor expression was found more frequently in variant type ILC than in classic type. These results suggest that the incidence of invasive lobular carcinoma of the breast in Japanese women is low and that unilateral multicentricity is not significantly higher in ILC than in IDC.

Immunoperoxidase staining for estrogen and progesterone receptors in archival formalin fixed, paraffin embedded breast carcinomas after microwave antigen retrieval

Immunoperoxidase staining was performed for estrogen and progesterone receptors in 93 cases of primary breast carcinoma. Breast tumor samples were fixed in formalin and embedded in paraffin. Antigen retrieval was performed by microwave heating in citrate buffer, pH 6.0, using precisely defined and reproducible conditions. The cases studied included material from the current year and from paraffin blocks retrieved from archival storage dating back to 1981. In all cases, estrogen and progesterone receptor values determined by biochemical assay were available for comparison with the immunohistochemical results. We found 94% agreement of results between the two methods.

Constitutive co-expression of estrogen and progesterone receptor mRNA in human meningiomas by RT-PCR and response of in vitro cell cultures to steroid hormones

Although it is well recognised that human meningiomas are rich in progesterone receptor (PgR), controversy has existed about the presence of the estrogen receptor (ER) in these tumours. We have investigated the presence of both ER and PgR in a series of 20 human meningiomas, spanning the main histological groups, using reverse transcription linked PCR (RT-PCR). Total RNA was extracted from whole tissues and reverse transcribed to yield cDNA. This was amplified using primers specifically designed to detect ER and PgR. All samples co-expressed ER and PgR mRNA, irrespective of tumour classification, patient age or sex. In general, transcripts for PgR appeared considerably stronger than those for ER, and although this was a purely qualitative study, it suggests increased expression of PgR. Addition of exogenous 17beta-estradiol or progesterone to meningioma cell cultures showed that 2/4 cultures responded to these steroids. Our results confirm that human meningiomas do express gene transcripts for ER, and that previous failures to detect ER in these tumours may be due to the lack of sensitivity of the techniques employed. However, these receptors may not be functional in all tumours.

Oestrogen and progesterone receptor assessment in core biopsy specimens of breast carcinoma

AIMS

To assess the suitability of core biopsy specimens for the immunohistological assessment of oestrogen and progesterone receptors in breast carcinoma.

METHODS

Thirty consecutive cases of clinically palpable breast carcinoma, from which both core and excision biopsy specimens were available, were examined. Routinely processed paraffin wax sections were stained using the specific monoclonal antibodies 1D5 (Dako) for oestrogen receptor and NCL-PGR (Novocastra) for progesterone receptor, after an antigen retrieval step using a pressure cooker. Staining results were assessed using the H score system with the results being expressed as negative, weakly positive, moderately positive or strongly positive.

RESULTS

Twenty six biopsy specimens contained enough tumour tissue for assessment. Absolute agreement between scoring categories was seen in 19 (73%) cases for oestrogen receptors. However, when all positive categories were added together, agreement between core and excision biopsy specimens increased to 93% (24 cases). Disagreement was seen only in two cases which stained positive in the core biopsy specimens and negative in the excision biopsy specimens. For progesterone receptors, the absolute agreement between all scoring categories was seen only in 11 (42%) cases. When all positive categories were considered together, agreement increased to 69% (18 cases). Five cases were progesterone receptor positive in core but not in excisional biopsy specimens, while three cases were negative in core but positive in excisional biopsy specimens.

CONCLUSIONS

The results suggest that core biopsy specimens can be reliably used for oestrogen receptor assessment, but are less reliable for progesterone receptor assessment, probably because of a greater heterogeneity of progesterone receptor staining.

Presence of exon 5-deleted oestrogen receptor in human breast cancer: functional analysis and clinical significance

A variant form of the human oestrogen receptor (ER) mRNA lacking sequences encoded within exon 5 has been described (Fuqua SAW, Fitzgerald SD, Chamness GC, Tandon AK, McDonnell DP, Nawaz Z, O'Malloy BW, McGuire WL 1991, Cancer Res 51: 105-109). We have examined the expression of the exon 5-deleted ER (HE delta5) mRNA variant in breast biopsies using reverse transcriptase polymerase chain reaction (RT - PCR). HE delta5 mRNA was present in only 13% of non-malignant breast tissues compared with 32% of carcinomas (95% CI, P=0.05). Presence of the HE delta5 mRNA was associated with the presence of immunohistochemically detected ER (P=0.015) and progesterone receptor (PR) (P=0.02). There was a positive correlation between the presence of HE delta5 and disease-free survival (P=0.05), suggesting that the presence of HE delta5 may be an indicator of better prognosis. We have raised a monoclonal antibody specific to the C-terminal amino acids of HE delta5. This antibody recognized the variant but not the wild-type ER protein. We show that HE delta5 protein is present in breast cancer using immunohistochemical techniques. We also analysed trans-activation by HE delta5 in mammalian cells and showed that, in MCF-7 cells, HE delta5 competes with wild-type ER to inhibit ERE-dependent trans-activation. Our results indicate that this variant is unlikely to be responsible for endocrine resistance of breast cancer, but its presence at both the mRNA and protein level suggest that it may, nevertheless, be involved in regulating the expression of oestrogen-responsive genes in breast cancer.

Comparison of two monoclonal antibodies for the detection of estrogen receptors in primary breast carcinomas

A new monoclonal antibody against estrogen receptor (ID5, Dako) has shown promising results when applied to formalin fixed, paraffin embedded tissue. In order to determine whether this antibody can compete in specificity and sensitivity with the ER-ICA antibody (Abbott Laboratories), a comparative, prospective study of the two antibodies was carried out on paraffin embedded and fresh frozen tissue in three laboratories. Two hundred and fifteen breast carcinomas were examined. Formalin fixed, paraffin embedded tissue was available from 215 tumors, and fresh frozen tissue from 189 of the tumors. Of these, 124 tumors were also investigated by the enzyme-linked immunosorbent assay. The results from each of the three laboratories correspond with those obtained for the whole material. The percentage of tumors positive for estrogen receptors within the different methods, was as follows: 71% by ID5 on paraffin sections, 50% by ER-ICA on paraffin sections, 65% ER-ICA on frozen sections and 88% by the EIA. When comparing the different immunohistochemical results and the EIA in 2 x 2 tables, agreement was reached in 69% to 91% of the cases. The best agreement (91%) was found between results obtained with the ID5 antibody used on formalin fixed, paraffin embedded tissue and the ER-ICA kit used on fresh frozen tissue. The advantages of using the ID5 antibody are associated with its applicability to formalin fixed, paraffin embedded tissue: improved morphology, reproducibility, retrospective studying and low costs. Finally, it is reproducible not only within the same laboratory but also among different laboratories.

Immunohistochemical assay for oestrogen receptors in paraffin wax sections of breast carcinoma using a new monoclonal antibody

The aim of this study was to evaluate the utility of a new monoclonal antibody (AER311) that targets the oestrogen receptor (ER) in an immunohistochemical assay (IHA) applied to breast cancers. Ninety-seven cases of invasive ductal carcinoma were studied by AER311-IHA using a pressure-cooking antigen retrieval technique applied to formaldehyde-fixed, paraffin-embedded tissue sections; immunostaining was assessed by semi-quantitative scoring (H score). There was 80 per cent concordance between the ER status measured by dextran-coated charcoal (DCC) assay and AER311-IHA, with 63/97 (65 per cent) tumours positive and 15/97 (15 per cent) tumours negative by both assays. Of the 12 DCC-positive cases that were negative by AER311-IHA, 11 were borderline positive (3-8 fmol/mg). Similarly, six of seven DCC-negative cases that scored positive by AER311-IHA had only borderline positive H scores (< 50). When AER311-IHA was compared with ID5-IHA, there was good concordance in ER status (77 per cent) and a significant correlation (r = 0.7, P < 0.001) between H scores. Nevertheless, the correlation between ER level determined by AER311-IHA and that measured by DCC (r = 0.53, P < 0.001) was higher than that for 1D5-IHA (r = 0.32, P = 0.002). AER311-IHA can therefore provide reliable information about the ER status of breast carcinoma on paraffin sections and is an acceptable alternative to other commercially available monoclonal antibodies.

Estrogen receptor immunocytochemistry in paraffin embedded tissues with ER1D5 predicts breast cancer endocrine response more accurately than H222Sp gamma in frozen sections or cytosol-based ligand-binding assays

BACKGROUND

Historically, estrogen receptor (ER) determinations have been made by the ligand-binding assay of tumor homogenates, primarily by the dextran-coated charcoal method (DCC). Immunocytochemical assays (ICA) for ER are more recent and have been executed mostly on frozen sections with the monoclonal antibody H222Sp gamma (H222). Lately, new monoclonal antibodies derived by recombinant ER technology have been developed that work well on paraffin embedded, formalin fixed tissue sections. However, there is little information as to whether such assays prognosticate endocrine response.

METHODS

Using antigen retrieval, the immunoglobulin G1 monoclonal antibody ER1D5, and the streptavidin-biotin detection system, 74 patients with breast cancer in whom endocrine response was known were assayed and the results compared with ER by DCC and ER by ICA in frozen section with H222.

RESULTS

ER1D5 in paraffin provided the highest correlation with endocrine response (Kendall's tau [r] = 0.57; P<0.001) whereas ER by DCC failed to correlate (r= -0.002; P<0.99). ER1D5 in paraffin correlated weakly though significantly with DCC (Kappa Statistic [K] = 0.204; P<0.02). H222 in frozen sections also correlated moderately with endocrine response (r = 0.34; P<0.001).

CONCLUSIONS

ER can be detected in routine tissue sections processed with antigen retrieval and ER1D5, and can be relied upon to provide accurate prognostic information regarding response to endocrine therapies in breast cancer patients.

Oestrogen receptor analysis of paraffin sections and cytosol samples of primary breast cancer in relation to outcome after adjuvant tamoxifen treatment. The South Sweden Breast Cancer Group

The aim of the present study was to compare oestrogen receptor (ER) analysis results obtained in cytosols of frozen breast cancer tissue (using biochemical assay) with those obtained in paraffin-embedded tissue (using immunoperoxidase staining with monoclonal antibodies (DAKO-ER, 1D5), and an ER positivity cut-off level of >10% stained nuclei). In 86% (84/98) of the samples the same ER status (28 negative and 56 positive) was obtained with both procedures. In eight cases, the paraffin section was ER positive but the corresponding cytosol sample ER negative, whereas six cases showed the opposite pattern. The ER positive subgroup manifested better outcome after adjuvant treatment than the ER negative subgroup (p = 0.003 (cytosol), and p = 0.004 (paraffin)). As compared with the percentage of stained nuclei, staining intensity yielded no additional information. Although the results of ER analysis of paraffin-embedded material seem promising, it is too early to prefer it to frozen tissue, though this would be useful when no frozen tissue is available.

New aspects in the histological diagnosis of breast carcinoma

The wide use of mammographic screening and breast conservation surgery, as well as the introduction of a variety of new morphological and immunohistological assessment methods, has markedly changed the practice of breast histopathology. These changes have led to the emergence of new macroscopic and microscopic interpretation demands and difficulties. It is hoped that in the future the role played by diagnostic histopathology in the management of breast cancer will continue to be refined, so that it can provide more detailed information about individual tumors that will help in deciding the most likely approach to obtain the best treatment results.

Multistep progression from an oestrogen-dependent growth towards an autonomous growth in breast carcinogenesis

We investigated the relationship between hormone receptor status and cellular proliferation in a series of proliferative epithelial breast lesions in an attempt to clarify the putative role of this interaction in the process of breast carcinogenesis. The separation of oestrogen receptor (ER) positive and ER negative cases revealed that in hyperplastic breast epithelium (with and without atypia) the ER positive cases had a higher proliferation rate than that of ER negative cases. Conversely, in ductal carcinomas (both in situ and invasive), ER negative cases had rates of proliferation higher than those observed among the ER positive cases. The observation of higher proliferation in ER positive benign proliferative breast lesions fits with the concept of an initial hormone-dependent status in breast carcinogenesis. According to this assumption, activation of ER by hormone increases the possibility that cells may undergo malignant transformation. Although we are limited by our static view of the process, our results point to the existence of successive steps of progression from a hormone-dependent towards an autonomous growth. The demonstration of higher proliferation in ER-negative carcinomas, from the in situ phase onwards, reinforces the hypothesis that breast cancer progression is paralleled by a progressive hormone independence.

Estimation of estrogen receptor content in fine-needle aspirates from breast cancer using the monoclonal antibody 1D5 and microwave oven processing: correlation with paraffin embedded and frozen sections determinations

We describe a method of immunocytochemically assessing estrogen receptor (ER) status on alcohol-fixed smears obtained by fine-needle aspiration (FNA) from breast cancer patients, using a commercially available monoclonal antibody (1D5) with microwave oven processing. A series of 31 cases of aspirates from breast cancer were analysed and the results were compared with assessment by ER immunocytochemical assay using the same procedure on formalin-fixed tissue and with assessment by ER-ICA assay on frozen sections. The results were scored semiquantitatively using a five grade scoring system. Of the 31 cases examined, 21 were positive at least by two methods and 10 were negative for all three determinations. The results obtained in the ER immunocytochemical assay on aspirates and paraffin-sections using the antibody 1D5 and those obtained on frozen sections using the antibody H222 were closely similar. In only one case was it not possible to interpret the reaction in the cytological specimen because there was a strong background in the smear. In general, we obtained more intense positivity with the antibody 1D5 in aspirates and formalin-fixed material than with the antibody H222 in frozen sections. The scoring results of the three methods were almost identical. We conclude that the application of ER method on alcohol-fixed smears will eliminate the need for using a special fixation procedure and will provide several advantages, such as: improvement in morphological concomitant analysis, utilization whenever malignancy is found without necessity to re-aspirate the patient, and adequacy of archival material.