Topoisomerase II alpha and II beta expression in childhood acute lymphoblastic leukaemia: relation to prognostic factors and clinical outcome.

BACKGROUND/AIMS: Many regimens used in the treatment of childhood acute lymphoblastic leukaemia (ALL) include Daunorubicin or Etoposide, which act as topoisomerase poisons. It has been suggested that there may be a relation between topoisomerase expression and response to topoisomerase poisons, based mainly on results from in vitro studies. Therefore, the aim of this study was to investigate this relation in a clinical setting and determine whether topoisomerase II alpha and II beta might be of predictive value in ALL. METHODS: Cellular expression of topoisomerases II alpha and II beta was assessed in 177 cases of ALL by immunohistochemistry using monoclonal antibodies to the two enzymes. The percentages of cell nuclei showing positive staining for topoisomerase II alpha and II beta expression were assessed. RESULTS: Taking the series as a whole, a clear separation of survival curves was seen with the established prognostic markers white blood cell (WBC) count, CD10 status, and sex. However, topoisomerase II alpha and II beta expression showed no relation to survival. No association was found between the topoisomerases and the prognostic markers CD10 and WBC count; however, topoisomerase II alpha expression was found to be related to sex, with expression being lower in girls (p = 0.002). CONCLUSIONS: These results suggest that the response to topoisomerase poisons cannot be predicted by the assessment of topoisomerase II alpha and II beta expression as defined by immunohistochemistry.

Expression of topoisomerase IIIalpha in normal and neoplastic tissues determined by immunohistochemistry using a novel monoclonal antibody.

Topoisomerases are nuclear enzymes that modulate the topological structure of DNA in order to facilitate cellular events such as replication and transcription. These enzymes are also the cellular targets of certain classes of chemotherapeutic agents termed topoisomerase poisons. A new human topoisomerase isoform, IIIa, was discovered in 1996, which is thought to have roles in genome stability and possibly chromosome separation during mitosis. It is possible that novel or existing anti-topoisomerase agents target topoisomerase IIIa, suggesting that this enzyme may have potential as a prognostic marker and chemotherapeutic target. In order to study expression patterns of topoisomerase IIIa we have produced a novel monoclonal antibody to human topoisomerase IIIa (TOPO3a-1A4), and used it to assess topoisomerase IIIa expression in a wide range of normal and neoplastic tissues. We have found that topoisomerase IIIa is expressed in a wide range of tissue types, with especially high concentrations in endothelial cells and stromal fibroblasts. No general relationship was observed between expression of topoisomerase IIIa and proliferation. Expression in neoplastic tissues often paralleled their normal counterparts, although certain tumours showed either increased (e.g. colonic adenoma) or reduced (e.g. gastric carcinoma, small cell carcinoma of bronchus) expression. If topoisomerase IIIa is found to be a target for chemotherapeutic agents, clinical response in different tumour types may be related to topoisomerase IIIa expression, which may be assessed using TOPO3a-1A4.

Monoclonal antibodies recognizing CD5, CD10 and CD23 in formalin-fixed, paraffin-embedded tissue: production and assessment of their value in the diagnosis of small B-cell lymphoma.

AIMS: Assessment of the expression of antigens CD5, CD10 and CD23 can be of value in the differential diagnosis of small B-cell lymphoma. Correct subclassification is important since optimal treatment regimes differ between the subtypes. The aim of this study was to generate monoclonal antibodies recognizing these antigens in paraffin-embedded tissue and to assess their efficacy using a panel of cases of small B-cell lymphoma of various subtypes. METHODS AND RESULTS: For each antibody synthetic recombinant protein and conventional murine hybridoma technology was employed. Monoclonal antibodies effective in formalin-fixed, paraffin-embedded tissue were successfully generated, designated NCL-CD5-4C7, NCL-CD10-270 and NCL-CD23-1B12, respectively. A series of 58 cases of small B-cell lymphoma including examples of each subtype (lymphocytic, follicle centre cell, mantle cell, marginal zone and lymphoplasmacytoid) was assembled and immunostaining for the respective antigens carried out using the monoclonal antibodies produced. Our results indicate that the antibodies are specific for their respective antigens and give the predicted phenotypic profile in the small B-cell lymphoma subtypes. CONCLUSIONS: These novel monoclonal antibodies may be of value in routine diagnostic practice.

NCL-CD10-270: a new monoclonal antibody recognizing CD10 in paraffin-embedded tissue.

CD10 (CALLA) antigen is expressed in a wide variety of epithelial and nonepithelial tissues, but its most significant application is in the diagnosis and classification of certain types of malignant lymphoma and leukemia. CD10 is expressed in a high percentage of cases of acute lymphoblastic leukemia (ALL), follicular lymphoma, Burkitt's lymphoma, and some hematopoietic tumors. Although the antigen is not lineage specific, CD10 expression is widely used to define subgroups within B-ALL and is a useful tool for detecting the presence of leukemic blasts in the bloodstream. Currently available monoclonal antibodies to CD10 have been found to be effective only in fresh-frozen tissue and for techniques such as flow cytometry. We have used a recombinant protein corresponding to the whole of CD10 to generate a monoclonal antibody that is effective in paraffin-embedded tissue sections. We have used this antibody to assay for the presence of CD10 on a range of normal and pathological tissues. Strong staining was seen in lymphoid germinal centers, renal tubules, glomeruli, syncytiotrophoblast, hepatic parenchymal canaliculi, B-lineage ALL, follicle center cell lymphoma, and a proportion of cases of large-B-cell lymphoma. We believe that this antibody will be of value in the characterization of malignant lymphoma, in particular the differential diagnosis of small-B-cell lymphoma and subtyping of lymphoblastic leukemia, as well as the investigation of the significance of expression of CD10 in other normal and pathological tissues.

New monoclonal antibodies to the T cell antigens CD4 and CD8. Production and characterization in formalin-fixed paraffin-embedded tissue.

We have generated a recombinant protein representing part of the CD4 molecule and a peptide representing an epitope of predicted high antigenicity on the CD8 molecule and employed these to generate mouse monoclonal antibodies using standard hybridoma protocols. The extracellular domain of the CD4 molecule was obtained by reverse transcription of mRNA from peripheral blood lymphocytes followed by polymerase chain reaction. The amplified gene fragment was cloned into an expression vector to allow a histidine-tagged fusion protein to be produced in Escherichia coli. Purified fusion protein was used to immunize mice. The CD8 monoclonal antibody was raised against a peptide consisting of 13 amino acids within the carboxyl-terminal region of the CD8 cytoplasmic domain. The antibodies showed appropriate reactivity on Western blotting. By heat pretreatment, these antibodies have been shown to be highly effective on paraffin-embedded tissue. In normal lymphoid tissue, the expected distribution of CD4 and CD8 lymphocytes was observed. In a series of 16 T cell lymphomas and B cell lymphomas, immunostaining results were compared with those obtained using reagents effective only in frozen tissue. A high degree of correlation was observed. These results suggest that NCL-CD4 and NCL-CD8 may be of value in the characterization of T cell disorders.

New monoclonal antibodies to oestrogen and progesterone receptors effective for paraffin section immunohistochemistry.

Assessment of oestrogen and progesterone receptors (ER and PgR) in breast cancer is widely used for the prediction of response to endocrine therapy and as a prognostic marker. Cytosolic assays have been replaced in many centres by immunochemical techniques, which have many advantages including applicability to small samples, simplicity, and cost-effectiveness. This study describes the generation and characterisation of two novel murine monoclonal antibodies recognizing ER and PgR, designated NCL-ER-6F11 and NCL-PGR respectively, which are effective in heat-treated formalin-fixed, paraffin-embedded tissue. The antibodies have been characterized by Western blotting and by immunohistochemistry on normal and pathological breast and other tissues. NCL-ER-6F11 has been shown to compare favourably with a currently available ER antibody. These antibodies may prove of value in the assessment of hormone receptor status in human breast cancer.

Immunolocalization and messenger RNA expression of bone morphogenetic protein-6 in human benign and malignant prostatic tissue.

Skeletal metastases are common in advanced prostate cancer, causing considerable morbidity, and they are usually osteoblastic in nature with no clear explanation for this phenomenon. Bone morphogenetic proteins (BMPs) induce bone formation in vivo, and preliminary work showed a possible association between BMPs and prostatic skeletal metastases; differential expression favors BMP-6 as a potential new marker and mediator of osteosclerotic deposit formation. We investigated BMP-6 mRNA and protein expression by in situ hybridization and immunohistochemistry in malignant and benign prostates from 40 men. BMP-6 mRNA expression was detected exclusively in malignant epithelial cells in 20 of 21 patients (95%) with metastases and in 2 of 11 patients (18%) with localized cancer, and it was absent in 8 benign samples. Immunostaining for BMP-6 was predominantly cytoplasmic and was present in all primary tumors with established metastases and in 4 of 11 (36%) organ-confined cancers. In benign prostatic hyperplasia, basal cells and areas of basal cell hyperplasia were positive for BMP-6 by immunohistochemistry. The results suggest a close association between BMP-6 expression in primary malignant prostatic tissue and skeletal metastases. BMP-6 may be responsible, in part, for the osteoblastic changes in metastatic lesions secondary to prostate cancer.

Prediction of nodal metastasis and prognosis in breast cancer: a neural model.

BACKGROUND: An increasing number of women with breast cancer are detected with the disease at an early stage, when the lymph nodes are not involved. In order to obviate the necessity to carry out axillary dissection, accurate surrogates for lymph node involvement need to be identified. In this paper we have examined the use of a neural network to predict nodal involvement. The neural approach has also been extended to investigate its predictive applicability to the long-term prognosis of patients with breast cancer. A number of established and experimental prognostic markers have been studied in an attempt to accurately predict patient outcome 72 months after first examination. METHODS: 81, unselected patients, presenting clinically, who had all undergone mastectomy for invasive breast carcinoma were considered in this study. A total of 12 markers were analysed for the prediction of lymph node metastasis, while node status itself was used as an additional marker for the prognostic analysis. In this case the outcome related to whether a patient had relapsed within 72 months of diagnosis. In both cases, a number of marker combinations were analysed separately in an attempt to classify those most favourable marker interactions with respect to lymph node prediction and prognosis. Patients were randomly divided into a training set (n = 50) and a test set (n = 31). The simulation was developed using the NeuralWorks Professional II/Plus software (NeuralWare, Pittsburgh, Pa, USA). RESULTS: In the case of lymph node metastasis, the neural network was able to correctly predict axillary involvement, or otherwise, in 84% of the patients in the test set by considering 9 of the 12 available markers. This represents an improvement of 10% over the traditional approach which considers the tumour grade and size only. The sensitivity and specificity were also shown to be 73% and 90%, respectively. With regard to patient prognosis, again 84% classification accuracy was obtained using a subset of the markers, with a sensitivity of 50% and a specificity of 96%. CONCLUSIONS: Although this study considered a relatively small sample of patients, nevertheless it demonstrates that artificial neural networks are capable of providing strong indicators for predicting lymph node involvement. There is no longer a need for axillary dissection with all its implications in patient morbidity and demands on clinical resources. The management of breast cancer and the planning of strategies for adjuvant treatments is also facilitated by the use of neural networks for the long-term prognosis of patients.

CHOP-based chemotherapy is as effective as alternating PEEC/CHOP chemotherapy in a randomised trial in high-grade non-Hodgkin's lymphoma. Scotland and Newcastle Lymphoma Group.

The aim of this study was to test whether survival for patients with high-grade non-Hodgkin's lymphoma (NHL) can be improved with a non-cross-resistant regimen as compared to a CHOP-based regimen. This is a multicentre study comprising 325 adult patients, median age 58 years, with high-grade non-Hodgkin's lymphoma: patients of any age and performance status were eligible provided they were able to receive the drugs in the regimens. Patients were randomised to either B-CHOP-M (bleomycin, cyclophosphamide, doxorubicin, vincristine, prednisolone and methotrexate) or PEEC-M (methylprednisolone, vindesine, etoposide, chlorambucil and methotrexate) alternating with B-CHOP-M. At a median follow-up of 9 years, there was no significant difference in overall survival or disease-free survival between the two arms. Toxicities for the two regimens were equivalent. This study confirms that for relatively unselected patients with high-grade non-Hodgkin's lymphoma, an alternating multidrug regimen does not improve upon the results obtained with B-CHOP-M.

The pathological and biological nature of screen-detected breast carcinomas: a morphological and immunohistochemical study.

Traditional and immunohistochemical markers of prognosis were examined in 455 mammary carcinomas derived from breast cancer screening and compared with those of 277 carcinomas presenting symptomatically over the same period. Tumours detected by population screening under the U.K. National Health Service Programme do not differ from those detected by other screening projects, but compared with symptomatic cancers, screen-detected cancers are more likely to be in situ and if invasive, to be smaller, of lower grade, and to have invaded vessels, perineural spaces, and lymph nodes less frequently. Tubular and cribriform types are more often represented in screened patients. Immunohistochemical markers which have been proposed as being related to likely tumour behaviour (epidermal growth factor receptor, c-erbB-2 protein, oestrogen and progesterone receptors, cathepsin D, p53, and retinoblastoma protein) do not distinguish screen-detected from 'clinical' cancers. It is concluded that cancers diagnosed at screening do not differ biologically from those presenting clinically, but are the same lesions detected at an earlier stage of their natural history.

A novel quantitative immunoassay system for p53 using antibodies selected for optimum designation of p53 status.

AIM: To develop a highly sensitive and specific enzyme linked immunosorbent assay (ELISA) system for analysis of p53 protein in cancer lysates. METHODS: The anti-p53 monoclonal antibodies DO7, 1801, BP53.12, and 421, and anti-p53 polyclonal antiserum CM1 were assessed by immunohistochemistry and western blot analysis to identify those most suitable for determining p53 status of cancer cells. Antibodies with desired characteristics were used to develop a non-competitive sandwich type ELISA system for analysis of p53 expression in cancer cytosols. Using the ELISA, p53 protein concentrations were measured in a small series of breast cancers, and the quantitative values compared with p53 immunohistochemical data of the same cancers. RESULTS: DO7 and 1801 gave the most specific and reliable results on immunohistochemistry and western blot analysis. Using these two antibodies, a non-competitive sandwich type ELISA system was developed to analyse p53 quantitatively. Analysis of the breast cancer series showed a good correlation between immunohistochemistry and the ELISA-tumours were generally positive using both techniques. Discrepancies were noted however: some cancers were immunohistochemically negative but ELISA positive. One explanation for this may be that the ELISA is more sensitive than immunohistochemistry. CONCLUSION: The p53 ELISA system is a non-competitive double monoclonal antibody sandwich method, using DO7 and 1801 which have been shown to be highly specific for p53 protein by immunohistochemistry and western blot analysis. The lower threshold of the assay is 0.1 ng/ml analyte in an enriched recombinant p53 preparation. As p53 is now regarded as a protein associated with prognosis in breast and other cancers, the assay may have clinical applications.

The expression of waf-1, p53 and bcl-2 in prostatic adenocarcinoma.

OBJECTIVE: To determine the associations between the expression of waf-1 (a cyclin-dependent kinase inhibitor regulated by p53), p53, bcl-2 and tumour progression in prostate cancer. PATIENTS AND METHODS: Samples of prostatic tissue were obtained by biopsy or at prostatectomy from 40 men (mean age 73 years, range 55-88) with histologically confirmed prostate cancer, examined using immunohistochemical staining for the three gene products, and the expression related to the stage, grade, disease progression and survival of the patients. RESULTS: Fifteen of 18 patients whose tumours were positive for waf-1, 10 of 12 positive for bcl-2 and 17 of 19 positive for p53 had disease progression. Fifteen of 19 patients positive for p53 had poorly differentiated tumours compared with 11 of 21 negative for p53 (P < 0.05). A significant number of patients positive for p53 progressed and had a shorter time to progression compared to those negative for p53 (P < 0.05). There was no correlation between either waf-1 and/or bcl-2 staining and clinical grade, stage or tumour progression. CONCLUSIONS: This study confirmed the association of p53 protein accumulation with aggressive behaviour in prostate cancer and identified waf-1 protein in prostatic tumours. There was no evidence that the upregulation of waf-1 was associated with a better outcome in patients with prostate cancer.

Production and characterization of a new monoclonal antibody effective in recognizing the CD3 T-cell associated antigen in formalin-fixed embedded tissue.

Phenotypic analysis of lymphoproliferative disorders is now considered mandatory for accurate classification which is the basis for optimum patient management. This is presently carried out in most cases using a range of antibodies recognizing B and T-cell antigens effective in paraffin sections, and an antibody to CD 3 is currently a key member of such panels, indicating T-cell phenotype. Current antibodies to CD3 are polyclonal with the inherent disadvantages of this type of reagent compared to monoclonal antibodies. In this study, we have used a recombinant fusion protein representing part of the epsilon subunit of the CD3 molecule to generate a novel monoclonal antibody (NCL-CD3-PS1) effective in paraffin sections. The antibody has been characterized biochemically and by immunohistochemistry using a wide range of normal and pathological tissues. Lineage and phenotype specificity have been supported in our study and results from other laboratories are awaited with interest.

The detection of nodal metastasis in breast cancer using neural network techniques.

Identification and treatment of involved axillary lymph nodes is important in the planning of strategies for adjuvant treatments of breast cancer. With the advent of the National Health Service Screening Programme, an increasing number of women with the disease are detected at an early stage, when the lymph nodes are not involved. In whom, therefore, is it necessary to carry out a formal axillary dissection? Are there accurate surrogates for lymph node involvement in the form of tumour markers or characteristics? This study, carried out on over 81 patients, examines the use of neural networks to predict the involvement of lymph nodes using readily available clinical and pathological data and also more specialized markers of possible prognostic significance. The study shows that neural networks are capable of providing strong indicators as to lymph node status using only basic measurements of the primary breast tumour. However, accuracy can be improved by the addition of less common markers.

Retinoblastoma protein in human breast carcinoma: immunohistochemical study using a new monoclonal antibody effective on routinely processed tissues.

Cyclic phosphorylation/dephosphorylation of the retinoblastoma gene product (pRB) has been found to play a central role in the progression of the normal cell cycle, through modulation of the activity of the E2F family of transcription factors. Mutations of the retinoblastoma gene have been described in a wide variety of human malignancies including carcinomas of the breast. The present investigation reports the production and application of a new monoclonal antibody in an immunohistochemical study of pRB expression in 233 primary breast carcinomas, allowing an assessment of the contribution made by this tumour suppressor gene to tumour development and progression. Overall, there was loss of pRB expression in 21 per cent of breast tumours. Although high-grade tumours were found to lack detectable pRB more frequently than low-grade tumours, the difference did not prove statistically significant. In addition, pRB immunostaining was not related significantly to relapse or survival. No significant correlations were observed between apparent loss of pRB and tumour size, parity, patient lymph-node status, p53, c-erbB-2, c-jun, EGFR or steroid hormone receptor expression. Preliminary findings, however, did suggest a relationship between pRB expression and response to endocrine therapy.

Cell adhesion molecules in bladder cancer: soluble serum E-cadherin correlates with predictors of recurrence.

Sera from 40 patients with newly diagnosed bladder cancer (28 superficial tumours (pTa and pT1) and 12 muscle-invasive tumours) were assessed by enzyme-linked immunosorbent assay (ELISA) to determine the concentrations of soluble E-cadherin (sE-cadherin), soluble E-selectin (sE-selectin), soluble vascular cell adhesion molecule-1 (sVCAM-1) and soluble intercellular adhesion molecule-1 (sICAM-1). Corresponding frozen sections of primary tumour were analysed for E-cadherin expression using the monoclonal antibody, HECD-1 and standard immunohistochemistry. Patients with bladder cancer had significantly higher concentrations of sE-cadherin compared with a control group (P = 0.017). No difference was found between the two groups with regard to sE-selection (P = 0.403), sVCAM-1 (P = 0.942) and sICAM-1 (P = 0.092). High levels of sE-cadherin were related to poor histological grade (P = 0.009), number of superficial tumours at presentation (P = 0.008) and a positive 3 month check cytoscopy in superficial disease (P = 0.036). Abnormal E-cadherin expression was associated with increasing tumour stage (P = 0.009) and grade (P = 0.03). There was no correlation between high levels of soluble E-cadherin in sera and abnormal E-cadherin expression by the tumour (P = 0.077). Elevated levels of sE-cadherin are found in sera of patients with bladder cancer and correlate with known prognostic factors.

c-erb B-2 and p53 expression in breast cancer fine needle aspirates.

The aim of this study was to co-evaluate c-erb B-2 and p53 protein expression in breast cancer fine needle aspirates (FNA) and to compare this with histological variables and the immunohistochemical phenotype of the tumours. Furthermore, we assessed the relationship of c-erb B-2 and p53 immunocytochemical expression to tumour prognostic factors. We examined 124 breast cancer FNAs and 79 matched surgical specimens using the avidin-biotin complex (ABC) and the alkaline phosphatase immunocytochemical techniques. C-erb B-2 immunopositivity was detected in 37.9% of the FNAs, while 31.7% were positive for p53. A statistically significant correlation was observed between p53 negativity and absence of c-erb B-2 immunostaining in the FNAs (P = 0.0007). Smears from infiltrating ductal carcinomas tended to be more frequently positive for p53 (36.7%) than those from lobular carcinomas (11.7%) (P = 0.054). In matched tumour tissues, c-erb B-2 was positive in 16.7% and p53 in 19% of cases. The immunocytochemical results for both c-erb B-2 and p53 were significantly correlated with the immunohistochemical results. There was no correlation between c-erb B-2 and p53 immunostaining, in both FNAs and tissues, and patients menopausal status, tumour size, grade and lymph node status.

p53 protein as a prognostic indicator in breast carcinoma: a comparison of four antibodies for immunohistochemistry.

We examined the reactivity of four p53-specific monoclonal antibodies--PAb 1801, p53-BP-12, D07 and CM1--on sections of formalin-fixed tissue collected from 245 breast carcinomas. Immunodetection of p53 varied between 37.6% and 46.6%. The greatest variation was observed among lobular carcinomas and low-grade tumors in which immunodetection varied between 8.3% and 27.3%. In contrast, immunodetection of p53 in invasive ductal carcinomas was subject to a lower degree of variability with between 40.6% and 49.7% of these tumours proving to be positive. In general, we found antibodies PAb 1801 and DO7 to be the most effective in immunolocalising p53. Immunodetection of p53 with each of the four antibodies was found to correlate strongly with tumour grade. In survival analysis, the results gained using antibody PAb 1801 proved to be of greatest statistical significance and to provide the strongest index of prognosis. A significant relationship was observed between immunodetection of p53 with each of the four antibodies and poor responsiveness to endocrine therapy. In addition, relationships were also observed between p53 immunostaining and tumour oestrogen receptor (ER) status as well as c-jun expression. We observed no correlation between abnormalities of the p53 and the Rb gene products or between elevated c-erbB-2 or epidermal growth factor receptor (EGFR) expression and immunodetection of p53.

C-erbB-2 in bladder cancer: molecular biology, correlation with epidermal growth factor receptors and prognostic value.

PURPOSE: To study the c-erbB-2 oncogene in primary transitional cell bladder cancer. MATERIALS AND METHODS: Ninety-five patients with known clinical follow-up and epidermal growth factor receptor (EGFr) status were studied for expression of c-erbB-2 by immunostaining. Possible mechanisms underlying increased staining for c-erbB-2 protein were investigated by analyzing DNA and RNA encoding c-erbB-2. RESULTS: Strong positive staining for c-erbB-2 was detected in 20 (21%) tumors, with weaker staining in a further 13 (14%). There was no correlation between increased staining for c-erbB-2 and tumor stage, grade, or EGFr status. There was a low rate of amplification of the c-erbB-2 gene (1 of 24) on Southern blotting with a higher rate of elevated c-erbB-2 mRNA (4 of 44) with dot blot hybridization. For pT1 tumors, the rate of recurrence was higher for those tumors which were positive for c-erbB-2. CONCLUSIONS: c-erbB-2 oncoprotein is expressed by a significant proportion of transitional cell tumors of the bladder. In this study, the prognostic significance of c-erbB-2 expression appears limited.

A flow cytometric study of c-erbB-3 expression in breast cancer.

In order to assess the specificity of biotinylated anti-c-erbB-3 antibody, screening was performed on a series of tumour cell lines and lymphocytes. Staining was found to be consistent, with good reproducibility. Twenty-nine consecutive breast cancer samples were obtained from women treated with tamoxifen and undergoing elective mastectomy. Twenty-eight invasive ductal carcinomas and 1 DCIS were stained for c-erbB-3 expression: 2 were grade I (Bloom and Richardson), 15 grade II, and 11 grade III tumours, 1 being unclassified; 16 were axillary node positive and 10 node negative; in 2 cases no nodes were sampled. Tumours examined by flow cytometry were stained with cytokeratin FITC antibody and the cytokeratin-positive population gated. Using Mann-Whitney analysis no association was seen between c-erbB-3 expression and Bloom and Richardson grade or axillary node status. In the tumour samples c-erbB-3 expression was found to show as association with EGF-R (P = 0.021 r2 = 0.16), PgR (P = 0.02, r2 = 0.16), c-myc (P < 0.0001, r2 = 0.5), c-jun (P = 0.001, r2 = 0.4) and c-fos (P = 0.001, r2 = 0.5) but not with c-erbB-2 (P = 0.2, r2 = 0.06), ER (P = 0.4, r2 = 0.02) or p53 1801 (P = 0.05, r2 = 0.2). Expression of c-erbB-3 may not be an independent marker of prognosis, but it is associated with other markers of poor prognosis and early cellular events linked with aberrant growth and differentiation.