Relationships between oestrogen receptor,epidermal growth factor receptor, ER-D5, and P24 oestrogen regulated protein in human breast cancer

Study on the Prognostic Values of Dynactin Genes in Low-Grade Glioma

OBJECTIVE

This present study aims to investigate the potential prognostic values of dynactin genes (DCTN) for predicting the overall survival (OS) in low-grade glioma (LGG) patients.

METHODS

The DCTN mRNA expression data were downloaded from The Cancer Genome Atlas database containing 518 patients with LGG. The Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses for DCTN genes were performed by using Database for Annotation, Visualization, and Integrated Discovery platform, and their enrichment results were verified by using the Biological Networks Gene Ontology tool. Next, the correlations between DCTN genes and LGG were identified by Pearson correlation coefficient analysis. The OS was estimated by Kaplan-Meier survival analysis. The cBio Cancer Genomics Portal was used to analyze the mutations of DCTN genes and their effects on the prognosis of LGG. The correlation between the abundance of immune infiltration and tumor purity of DCTN genes were predicted by The Tumor Immune Estimation Resource.

RESULTS

Our research showed that the mRNA expression of DCTN4 in tumor tissues was much higher (P < 0.01) than that in normal tissues. Meanwhile, there was a certain correlation between the DCTN genes. Survival analysis showed that the high expression of DCTN1, DCTN3, DCTN4, DCTN6, and their co-expression were significantly correlated with favorable OS in LGG patients (P < 0.05). In DCTN2, a high mutation rate was observed. Further research showed that the genetic alteration in DCTN genes was related to a poor OS and progression-free survival of LGG patients. The expression of DCTN genes had a certain correlation with immune infiltrating cells.

CONCLUSION

Our study showed that the high expressions of DCTN1, DCTN3, DCTN4, and DCTN6 were associated with a favorable OS of LGG patients, indicating that these DCTN genes are potential biomarkers for evaluating the prognosis of LGG patients.

Combined lentiviral and RNAi technologies for the delivery and permanent silencing of the hsp25 gene

Elevated heat shock protein 27 (Hsp27) expression has been found in a number of tumors, including breast, prostate, gastric, uterine, ovarian, head and neck, and tumor arising from the nervous system and urinary system, and determined to be a predictor of poor clinical outcome. Although the mechanism of action of Hsp27 has been well documented, there are currently no available inhibitors of Hsp27 in clinical trials. RNA interference (RNAi) has the potential to offer more specificity and flexibility than traditional drugs to silence gene expression. Not surprisingly, RNAi has become a major focus for biotechnology and pharmaceutical companies, which are now in the early stages of developing RNAi therapeutics, mostly based on short interfering RNA (siRNAs), to target viral infection, cancer, hypercholesterolemia, cardiovascular disease, macular degeneration, and neurodegenerative diseases. However, the critical issues associated with RNAi as a therapeutic are delivery, specificity, and stability of the RNAi reagents. To date, the delivery is currently considered the biggest hurdle, as the introduction of siRNAs systemically into body fluids can result in their degradation, off-target effects, and immune detection. In this chapter, we discuss a method of combined lentiviral and RNAi-based technology for the delivery and permanent silencing of the hsp25 gene.

Antiangiogenic strategies in breast cancer management

Angiogenesis is considered one of the key mechanisms of tumour growth and survival. Therefore it represents an ideal pharmaceutical target. Many antiangiogenic agents have been developed so far in several solid tumours and also in breast cancer. Vascular endothelial growth factor (VEFG) is the main target and both monoclonal antibodies and small molecules belonging to the tyrosine kinase inhibitors directed against VEGF(R) have been developed. Some other therapeutic approaches have shown to exert some antiangiogenic activity, such as hormonal agents, metronomic chemotherapy, bisphosphonates and others. In this paper we provide an introduction of the current data supporting the angiogenesis in breast cancer and a review of the most relevant antiagiogenic therapies which have been investigated so far.

A phase II placebo-controlled trial of neoadjuvant anastrozole alone or with gefitinib in early breast cancer

PURPOSE

Increased epidermal growth factor receptor (EGFR) expression may promote breast cancer resistance to endocrine therapy. We have therefore investigated whether neoadjuvant gefitinib, an EGFR inhibitor, might overcome biologic and clinical resistance to neoadjuvant anastrozole in a phase II placebo-controlled trial.

PATIENTS AND METHODS

Postmenopausal women with stage I to IIIB hormone receptor-positive early breast cancer received anastrozole 1 mg daily for 16 weeks and were randomly assigned at a ratio of 2:5:5 to receive, in addition, gefitinib 250 mg/d orally for 16 weeks: placebo 1 tablet/d orally for 2 weeks and then gefitinib for 14 weeks or placebo for 16 weeks. The primary end point was biologic change in proliferation as measured by Ki67 at 2 and 16 weeks; the main secondary end point was overall objective response (OR).

RESULTS

Two hundred six women were randomly assigned. Mean changes in Ki67 with anastrozole and gefitinib versus anastrozole alone were -77.4% and -83.6%, respectively, between baseline and 16 weeks (geometric mean ratio = 1.37; 95% CI, 0.79 to 2.39; P = .26), -80.1% and -71.3% between baseline and 2 weeks (geometric mean ratio = 0.70; 95% CI, 0.39 to 1.25; P = .22) and -19.3% and -43% (geometric mean ratio = 1.42; 95% CI, 0.86 to 2.35; P = .16) between 2 and 16 weeks. ORs in the combination and anastrozole alone groups were 48% and 61% (estimated difference = -13.1%; 95% CI, -27.3% to 1.2%), respectively, with a nonsignificant trend against the combination (P = .08) and 48% versus 72% (estimated difference = -24.1%; 95% CI, -45.3% to -2.9%) in the progesterone-receptor-positive subgroup, which was significant (P = .03) and consistent with Ki67 changes. Common treatment-related adverse events included diarrhea, rash, alopecia, dry skin, and nausea. There was no evidence of a pharmacokinetic interaction.

CONCLUSION

Addition of gefitinib to neoadjuvant anastrozole had no additional clinical or biologic effect, failing to support our original hypothesis.

Analysis of the level of mRNA expression of the membrane regulators of complement, CD59, CD55 and CD46, in breast cancer

We have examined the relative mRNA expression of the complement (C) regulatory proteins CD59, CD55 and CD46 in RNA isolated from 50 primary breast cancer specimens using a semiquantitative RT-PCR approach. Having normalized the mRNA expression levels of the C regulators relative to actin, we subsequently correlated their expression with estrogen receptor (ER) and various clinical, pathologic and biochemical features of the disease. CD59 and CD46 were detected in all clinical biopsies, while CD55 mRNA was detected in the majority of samples. The comparative levels of expression between the 3 regulators analyzed, using Spearman rank correlation test, revealed a significant association (p = 0.01; r = 0.36) between CD46 and CD59. CD46 exhibited the most striking pattern of association, with increased levels of expression being associated with ER-positive samples and lower levels of expression associated with a loss of differentiation and epidermal growth factor receptor positivity. Application of Spearman rank correlation test revealed CD46 expression was significantly associated with expression of ER at the level of protein (p = 0.031; r = 0.31) and mRNA (p < 0.001; r = 0.52). CD46 expression also correlated with insulin-like growth factor receptor-positive samples using Spearman rank correlation test (p = 0.016; r = 0.34), but negatively associated with tumor samples either exhibiting histologic grade 3 when compared to grades 1 or 2 or displaying elevated levels of inflammatory cell infiltrate. Immunohistochemical analysis of a limited series (n = 8) of paraffin-embedded breast cancers indicated that the level of CD46 protein expression directly associates with that of the mRNA and, where prominent, is localized in the tumor epithelial cell population, including at the plasma membrane. These data provide new information on expression of these important regulators in breast cancer and suggest that CD46 should be evaluated as a novel prognostic indicator.

Expression of ER-D5 and EGFr in laryngeal carcinoma and pre-malignant epithelium

The expression of estrogen receptors was biochemically assessed in a series of 46 cases of consecutive laryngeal carcinomas. ER-D5 and EGFr were also immunohistochemically detected in 44 and 46 cases respectively. There was no correlation between the expression of these molecules and the typical anatomo-clinical prognostic parameters of laryngeal tumors. The concomitant expression of estrogen receptors, ER-D5 and EGFr was also investigated in normal, hyperplastic and dysplastic epithelium. An increasing expression of ER-D5 and EGFr from normal to hyperplastic and dysplastic epithelium was noted. These data suggest a possible role of hormone receptors in the laryngeal carcinogenesis.

Comparison of radioligand assay and immunostaining for epidermal growth factor receptor in human breast cancer

Epidermal growth factor (EGF) receptor status is a useful prognostic indicator in women with breast cancer. Lack of standardization and correlation of methodology for the detection of EGF receptor has hampered its further evaluation. EGF receptor status was ascertained by immunohistochemistry and radioligand assay in 120 breast cancers. Of 52 tumours negative for EGF receptor on radioligand assay, 47 were negative on immunohistochemistry and, of 68 tumours positive for the receptor on assay, 52 were positive on immunohistochemistry. If the more widely evaluated radioligand assay is assumed to be the 'gold standard', immunohistochemistry has a sensitivity of 81 per cent and a specificity of 91 per cent.

Heat shock proteins and drug resistance

Heat shock proteins (hsp's) are induced in cells when exposed to different environmental stressful conditions. We have found that breast cancer cells sometimes express high levels of several hsp's, which may both augment the aggressiveness of these tumors and make them more resistant to treatment. We have shown that hsp70 is an ominous prognostic sign as detected by Western blot assays in node-negative breast tumors, and that hsp27 increases specific resistance to doxorubicin in breast cancer cell lines. These findings have direct clinical application, and suggest that modulating hsp expression may be a therapeutic target for reversal of hsp-associated detrimental cellular effects.

Oestrogen receptor, progesterone receptor, pS2, ERD5, HSP27 and cathepsin D in invasive ductal breast carcinomas

Hormonal receptors and markers for prognostic evaluation were detected immunohistochemically in 196 infiltrating ductal breast carcinomas. Immunohistochemical detection of progesterone and oestrogen receptor is a method giving results generally concordant with those of the binding assay. However, immunohistochemical detection seems better. It allows the detection of hormonal receptors on small carcinomas, it is not modified by the endogenous hormones, and it has a slightly better correlation with prognosis and with the response to hormone therapy. Immunohistochemical detection of progesterone receptor has a prognostic value, sorting a negative subgroup with a poor prognosis from the oestrogen receptor positive tumours. These results can be obtained without quantitative immunohistological methods. ERD5, pS2, HSP27 and cathepsin D are associated with oestrogen receptor positivity. pS2 and HSP27 are interesting markers. They characterize a subgroup of oestrogen receptor negative tumours with a good prognosis. Moreover, pS2 is a marker of response to hormone therapy. ERD5 and cathepsin D do not appear to be of value as markers of prognosis.

Immunohistochemical study of estrogen receptors and the responsiveness to estrogen in papillary thyroid carcinoma

BACKGROUND

Epidemiologic data suggested that the differentiated thyroid carcinoma was affected by sex hormones, especially estrogen.

METHODS

The authors have immunohistochemically studied estrogen receptors (ER) in papillary thyroid carcinoma in women. Two anti-ER monoclonal antibodies, D5 and H222, were used. The authors then investigated the responsiveness to estrogen of thyroid neoplasms using primary culture of surgically resected thyroid tissues. The proliferative activity of cultured cells was measured by the bromodeoxyuridine (BrdU) labeling index (LI).

RESULTS

Twenty-six percent of the specimens (18/70) showed positive staining with D5, but only 5.6% of the specimens (2/36) showed positive staining with H222. The BrdU LI of ER-positive papillary thyroid carcinoma increased with the addition of estradiol.

CONCLUSIONS

These findings indicate that estrogen may affect the proliferation of ER-positive papillary thyroid carcinoma.

Immunohistochemical study of estrogen receptor and estradiol on papillary thyroid carcinoma in young patients

We have immunohistochemically examined estrogen receptors (ER) and estradiol (E2) on papillary thyroid carcinoma in young females under the age of 25 years. The 10 young females in this study were compared with 64 females 30 years of age or older who underwent surgery for treatment of papillary thyroid carcinoma. We did not find any significant difference in the incidences of positive staining for E2 between the two groups. Of the specimens obtained from the young patients, 80% (8/10) showed positive staining for ER; this was significantly higher (P < 0.01) than that observed in patients 30 years of age or older (25%). We think that, especially in youth, estrogen may play an important role as a promoting factor. This indication needs further study.

Prognostic value of epidermal growth factor receptor expression in cervical carcinoma

AIMS

To investigate the pattern of epidermal growth factor receptor expression and its prognostic value in the three main types of cervical carcinoma.

METHODS

62 cases of stage IB/IIA cervical carcinoma, all with a minimum of five years of follow up, were studied. Representative sections were stained for mucin to permit accurate tumour typing and a standard avidin-biotin immunoperoxidase technique using the polyclonal antibody 12E was used to demonstrate the presence of epidermal growth factor receptor.

RESULTS

A proportion of all three tumour types expressed epidermal growth factor receptor, it being most common in squamous cell carcinomas (50%). Overall, there was a correlation between epidermal growth factor expression and mortality. This was particularly obvious in the absence of lymph node metastases. When the individual tumour types were considered this association with prognosis was not demonstrable for squamous cell carcinomas or adenocarcinomas but was a very prominent feature of adenosquamous carcinomas.

CONCLUSIONS

Immunohistochemical demonstration of epidermal growth factor receptor expression may be useful in identifying those patients with a poor prognosis, particularly those with adenosquamous carcinomas which have not metastasised to the regional lymph nodes.

Relationship between c-erbB-2 protein product expression and response to endocrine therapy in advanced breast cancer

Of 221 patients with breast cancer of known epidermal growth factor receptor (EGFR) and oestrogen receptor (ER) status, 99 had developed recurrences during the period of follow-up (range 3-60 months, median 24 months). Of these, 72 received endocrine therapy as first-line treatment for relapse. Immunohistochemical assessment of c-erbB-2 protein product expression was made using paraffin-embedded tumour tissue from 65 of these 72 patients. Including patients whose disease remained stable for more than 6 months with those showing an objective response (CR or PR for more than 3 months), only one (7%) of 14 c-erbB-2 positive tumours responded to endocrine manipulation compared with 19 (37%) of 51 c-erbB-2 negative tumours (P less than 0.05). Coexpression of c-erbB-2 reduced the response rate of ER positive patients from 48% to 20% and of ER negative cases from 27% to 0% (P less than 0.01). EGFR and c-erbB-2 protein appeared to have additive effects in reducing the likelihood of response, and none of eight patients with EGFR positive, c-erbB-2 positive tumours derived benefit from endocrine therapy. The results of this study suggest that c-erbB-2 protein overexpression, a marker of poor prognosis in breast cancer, is associated with a lack of response to endocrine therapy on relapse, and particularly in combination with EGFR may be useful in directing therapeutic choices.

Epidermal growth factor receptors in human breast cancer: a plea for standardisation of assay methodology

In a prospective study 200 primary human breast cancer specimens were analysed for epidermal growth factor receptor (EGFR) content by means of a multiple point ligand binding assay, proposed by the EORTC Receptor Study Group to be the standard EGFR assay. In 54% of the tumours the presence of saturable high affinity binding sites for epidermal growth factor could be demonstrated. The median EGFR level was 34 fmol/mg of membrane protein, the median Kd 0.50 nmd. Univariate analysis of the EGFR data stratified according to patient age, menopausal status, tumour size, axillary lymph node status, histological tumour type, tumour differentiation grade or the tumours' steroid hormone receptor status showed EGFR to be positively associated with younger age (P = 0.03), tumour dedifferentiation (P = 0.04) and steroid hormone receptor negativity (P less than 0.001). No association between EGFR and menopausal status, tumour size, axillary lymphnode status or histological tumour type could be demonstrated.

Determination of estrogen receptors in paraffin-embedded tissue. Techniques and the value in breast cancer treatment

Estrogen receptor (ER) analysis in breast cancer has been used in three clinical situations: to select patients with advanced breast cancer for hormonal therapy, as a prognostic parameter, and for selection of women with early breast cancer to adjuvant hormonal treatment. ER has traditionally been measured using labelled hormone in binding assays--often in dextran-coated charcoal assays (DCC). Monoclonal antibodies to ER has permitted development of a solid phase enzyme immunoassay (ER-EIA) used for quantitative determination of ER in tissue homogenates, and have also been used for determination of ER using an immunohistochemical assay in frozen sections (ER-ICA) or in formalin-fixed, paraffin-embedded tissue (ER-PAR). A large number of studies has compared ER-EIA with ER-DCC assays. There is a good linear correlation between the two types of assay but ER-EIA measure more ER and classify a larger fraction of tumors ER-positive than conventional ER assays. Lack of clinical data makes the significance of this uncertain. Numerous studies have reported on the correlation between ER-ICA and ER-DCC or ER-EIA. There is a good correlation among the assays on classification of ER status with a median 86% concordance, but a somewhat poorer correlation between semiquantified ER of immunohistochemical assays and ER determined by the quantitative methods (median coefficient of correlation 0.67). There is a large variation in the cut-off level for definition of ER-positive in immunohistochemical assays emphasizing the need for quality control studies. The major problem involved in ER analysis in paraffin-embedded tissue is a considerable loss of immunoreactivity compared to sections from frozen tissue. This can partly be overcome by modifications of the immunohistochemical technique using enzyme pretreatment and other amplification systems, but the sensitivity of ER-PAR remains lower than ER-ICA despite these modifications, and the ER status is less reliably determined in tumors with low ER contents (< 100 fmol). The prognostic value of ER-PAR was evaluated with a multivariate analysis. The endpoint was disease-free interval in systemically untreated patients with early breast cancer, and the variables used were: ER-DCC, ER-PAR, age, tumor size, tumor grade, and nodal status. A total of 133 patients from the Danish Breast Cancer Cooperative Group's (DBCG) 77c protocols had a complete set of variables. The analysis showed that only nodal status, ER-DCC, and tumor grade were significant and independent prognostic variables. An overview of larger multivariate studies on mainly node-negative patients failed to show independent prognostic significance of ER-DCC.(ABSTRACT TRUNCATED AT 400 WORDS)

Immunohistochemical and other features of breast carcinomas presenting clinically compared with those detected by cancer screening

Features of 111 mammary carcinomas derived from breast cancer screening were compared with those of 69 carcinomas presenting 'clinically'. Screen detected cancers were smaller, had less likelihood of nodal metastases, included a higher proportion of in situ tumours and if invasive, tended to be of lower grade. Using immunohistochemical methods, the expression of c-erbB-2 oncoprotein, epidermal growth factor receptor (EGFR) and cathepsin D were compared in the two groups. A similar proportion of screened and unscreened tumours expressed c-erbB-2 oncoprotein and EGFR but expression of the oestrogen regulated protein cathepsin D was significantly more frequent in the screened group (P less than 0.05). Although a relatively small series, the results suggest a biological difference between 'screened' and 'clinical' tumours.

Long-term survival in breast cancer related to overexpression of the c-erbB-2 oncoprotein: an immunohistochemical study using monoclonal antibody NCL-CB11

In a previous series we have shown poor short-term (3-5 years) survival for patients with tumours overexpressing the c-erbB-2 oncoprotein. In this study we employed archival paraffin-embedded tissue from patients who underwent mastectomy 10-12 years prior to assessment (n = 187). Immunohistochemical staining was carried out by an indirect immunoperoxidase technique using the novel monoclonal antibody NCL-CB11. Tumours were scored according to intensity of membrane staining. Patient and tumour information was obtained by scrutiny of clinical records. Survival analysis was carried out for both time to relapse and time to death, using the log rank test. Patients with tumours demonstrating intense membrane staining had a poor prognosis compared with the rest, with a steeply sloped survival curve over the first 4 years; the survival difference was still evident at 12 years follow-up (P less than 0.001). The survival advantage for c-erbB-2 negative patients was maintained in lymph node negative patients (P less than 0.001). However, c-erbB-2 status did not influence survival in the node positive group, where all patients had a uniformly poor outlook. These results applied to both time to relapse and time to death. In conclusion, c-erbB-2 status, determined using NCL-CB11, is a powerful prognostic indicator, defining in particular node negative patients with a particularly poor prognosis, and for whom alternative therapeutic strategies may be appropriate.

Colocalization of estrogen and progesterone receptors with an estrogen-regulated heat shock protein in paraffin sections of human breast and endometrial cancer tissue

We have studied by immunocytochemistry and monoclonal antibodies the presence and localization of estrogen receptors, progesterone receptors, and a 24-kD estrogen-regulated heat shock protein in biopsies from breast and endometrial cancer patients. Three different tissue processing protocols were used to colocalize the antigens in the same tissue sections: a) frozen sections, b) formalin fixation with routine paraffin embedding, and c) picric acid-formaldehyde (PAF) fixation with a rapid embedding in paraffin. Frozen sections showed good receptor staining but poor 24-kD protein immunoreactivity, while routine paraffin sections (with or without DNase pretreatment) were inadequate to reveal the nuclear receptor proteins at the same level seen in frozen sections. On the other hand, all three proteins could be detected satisfactorily in PAF-fixed paraffin-embedded tissue. Using this procedure we were able to visualize 24-kD protein and estrogen receptor or progesterone receptor in individual cells in paraffin sections. The study revealed that in all of the estrogen receptor positive breast and endometrial tumor samples, almost 90% of the cells expressing the cytoplasmic 24-kD protein contained estrogen receptor in the cell nucleus. In contrast, 24-kD immunoreactive cells did not express progesterone receptors in almost 40% of the progesterone receptor positive tumor samples.

neu oncogene protein and epidermal growth factor receptor are independently expressed in benign and malignant breast tissues

The neu oncogene protein, p185, and epidermal growth factor receptor (EGFR) were localized immunohistochemically in benign and malignant human breast tissues using monoclonal antibodies. Both benign and malignant epithelial cells were positive for these oncogene proteins in acetone-postfixed frozen sections. Stromal cells were negative for p185, but occasionally positive for EGFR. Myoepithelial cells were consistently positive for EGFR, and p185 was localized predominantly in duct-lining cells, where the basolateral plasma membrane was the normal expression site of both substances. Paraformaldehyde-prefixed frozen sections were less sensitive for antigen demonstration. Based on the intensity of immunoreactivity, 11 of 37 acetone-postfixed breast carcinomas (30%) were judged neu overexpressors, while none of 24 benign tissues overexpressed neu. Epidermal growth factor receptor was demonstrated in 18 of 36 acetone-postfixed cancer tissues (50%) and was overexpressed in three (8%). At the cellular level, heterogenous expression of p185 and EGFR was occasionally observed in both benign and malignant tissues, and a single case of cancer overexpressing both neu and EGFR showed reciprocal patterns of staining, indicating their independent expression. In some carcinomas, EGFR was localized only in stromal cells. Our findings confirmed mutually independent expression of the two closely related protooncogenes in benign and malignant breast tissues.

Breast cancers with extremely high oestrogen receptor protein status

Seventeen cases of primary and one case of metastatic breast cancer which expressed greater than 900 fmol oestrogen receptor sites per mg soluble protein were examined. All these patients were post-menopausal at the time of their presentation. These were a heterogeneous group of well-differentiated cellular breast carcinomas, comprising cases of invasive duct carcinoma with extensive tubular differentiation or with focal argyrophilia, tubulolobular carcinoma, lobular carcinoma of mixed type containing abundant intracytoplasmic lumina, papillary carcinoma and type B colloid carcinoma. There was very little tumour necrosis. Nodal metastasis, tumour size and host inflammatory response did not appear to show any relationship with oestrogen receptor status. The patients, apart from two who died from other causes, remain alive (Fisher's exact test, P less than 0.01). In contrast, 17 randomly selected cases of oestrogen receptor negative breast cancer in the same study period were focally necrotic, poorly-differentiated invasive duct carcinomas. Six patients died from metastatic disease, seven were alive and well, one was alive with metastatic disease, one was lost to follow-up and two died from diseases unrelated to breast cancer.

Inverse relationship between estrogen receptor and epidermal growth factor receptor mRNA levels in human breast cancer cell lines

Epidermal growth factor receptors (EGF-R) are present in a number of human breast cancer cell lines and tumor biopsies. Furthermore, it has been suggested that EGF-R levels are higher in estrogen receptor negative (ER-) than in ER+ human breast tumors and that EGF-R status may be a prognostic indicator in breast cancer. The present study was undertaken to establish whether there is a quantitative relationship between EGF-R and ER mRNA concentrations in a series of 10 well-characterized human breast cancer cell lines. All cell lines expressed detectable quantities of EGF-R mRNA by Northern analysis but the relative abundance of EGF-R mRNA varied more than 50-fold. Two transcripts corresponding to the 10.5- and 5.8-kb mRNAs described in other cell types were present but in different relative proportions in different cell lines. When these lines were divided into an ER+ and an ER- group based on their ability to bind estradiol, ER- cell lines were shown to express significantly higher concentrations of EGF-R mRNA than did ER+ cell lines (p less than 0.005). Furthermore, linear-regression analysis revealed a significant inverse relationship between ER and EGF-R mRNA concentrations both within the group of 10 human breast cancer cell lines as a whole (r = 0.66) and within the 6 functionally ER + lines (r = 0.77). This demonstration of a significant (p less than 0.005) inverse relationship between the concentrations of ER and EGF-R mRNAs in ER + cell lines raises the possibility of reciprocal regulation of the expression of these genes in human breast cancer.

Prognostic parameters in breast cancer

Carcinoma of the breast is the most common cancer in Australian women. Current methods of treatment and refinements in therapeutic regimens are based on our understanding of the biological behaviour of the disease. Several prognostic parameters have been identified which predict survival and allow the selection of patients who may benefit from adjuvant therapies. The more important of these parameters include tumour size, histologic type, histologic grade, axillary lymph node status, estrogen receptor status and tumour growth fraction. Diagnostic pathologists who are responsible for the evaluation of these parameters should be cognizant of their relative prognostic values and also of other factors such as cellular antigens, lectin binding and oncogenes which may have potential roles in predicting survival and therapeutic responses. This review provides an update of prognostic parameters which are assessed through examination of the excised specimen.

Immunohistochemical expression of epidermal growth factor receptor in salivary gland tumours

Immunohistochemical localization of epidermal growth factor receptor (EGFR) in normal salivary glands and tumours (108 cases) was studied using a monoclonal antibody. In the normal salivary glands, EGFR was occasionally detected in ductal segments of intercalated, striated, and excretory ducts, but not in acinar cells. The frequency of positive EGFR staining in salivary gland tumours was not high: pleomorphic adenoma, 33.8%; mucoepidermoid tumour, 25.0%; adenolymphoma, 44.4%; and sialoadenocarcinoma, 66.6%. Pleomorphic adenomas showed positive staining for EGFR on the luminal side of luminal cells and in squamous metaplastic cells of tumour tissue. Some modified myoepithelial cells were also reactive whereas outer spindle tumour cells were unstained. Adenolymphomas regularly exhibited positive EGFR staining in the cell membrane; mucoepidermoid carcinoma displayed positive staining in cell membranes in epidermoid tumour cells and cytoplasmic staining in mucous-secreting tumour cells. Sialocarcinomas revealed cell membrane staining and whole cytoplasmic staining for EGFR. The immunohistochemical localization of EGFR could be classified into two types, one the cell membrane-positive type found in epithelial tumour cells, and the second the cytoplasmic positive type seen in normal ductal cells, the luminal tumour cells of pleomorphic adenomas and mucous-secreting tumour cells.

Expression of epidermal growth factor receptor in benign and malignant primary tumours of the breast

Using the monoclonal antibody EGF-R1, normal mammary gland and a series of 213 unselected primary breast tumours were investigated immunohistochemically for expression of epidermal growth factor receptor (EGFR). In normal breast EGFR was expressed in variable patterns in lobular, ductal, and myoepithelial cells. In fibroadenoma, EGFR was detectable in variable numbers of ductal and myoepithelial cells and in stromal fibroblasts. The myoepithelial compartment of 2 cystosarcomas phyllodes also expressed EGFR. Among the 197 carcinomas tested only 20.3% contained EGFR expressing tumour cells which represented a minority in 12.2%, the majority in 2.1%, and the entire neoplastic population in 6.1% of the cases. Again, non-neoplastic ductal remnants often contained EGFR positive myoepithelial and ductal cells whereas stromal fibroblasts expressed EGFR only occasionally. We conclude that in contrast to the normal state, EGFR-expression is a rather rare phenomenon in breast carcinoma cells, positively correlated with a declining grade of differentiation (p less than 0.025) and at least occasionally associated with squamous metaplasia within the tumour, that EGFR expression is not exclusively restricted to cells of the epithelial lineage, and that EGFR may have other functions not related to proliferation, since it is commonly detectable in myoepithelial cells.