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Background: Breast cancer is characterized by malignant transformation of epithelial cells, but stromal cells also play an important role in tumorigenesis. While tumor-derived fibroblasts display unique phenotypic properties, it is unclear whether they also represent are a specific subpopulation., Materials and Methods: Stromal fibroblasts deriving from malignant tissue of 10 women with invasive breast cancer, and from normal breast tissue of 10 women with benign breast disorders, were subjected to differential complementary DNA Microarray Analysis by using a 2,400 gene cDNA array. Individual gene expression pattern were confirmed by RT-PCR., Results: In a cDNA array that allows to analyze the differential gene expression of more than 2,400 genes, the mRNA expression of 135 genes were increased more than 2 fold in fibroblasts from malignant breast tumors. The majority of these genes encode tumor-promoting cytokines, transcription factors and cell-matrix associated proteins. The mRNA expression of 110 genes decreased to less than 0.5 fold. The remaining 2,155 genes were not significantly altered. RT-PCR performed on individual biopsies from breast cancer and normal breast tissues confirmed the validity of the pooled gene expression signature., Conclusion: Breast cancer-derived stromal fibroblasts show a distinctive gene expression pattern that differentiates them from normal breast stroma. Our observation of increased expression of tumor promotion-associated genes even in the absence of adjacent malignant epithelium suggests that tumor stroma is comprised of a fibroblastic subpopulation that provides for a microenvironment which supports tumor growth and invasion.

cDNA arrays provide a powerful tool to identify gene expression pattern that are potentially associated with tumor invasion and metastasis. However, genes work at the protein level and, since the transcriptional activity of a gene does not necessarily reflect cellular protein expression, the identification and quantification of proteins is essential for the understanding of molecular events leading to malignant transformation. We have therefore employed a high-throughput protein microarray system which contains 378 well-characterized monoclonal antibodies in order to compare the gene expression pattern of malignant and adjacent normal breast tissue in a patient with primary breast cancer. Using this technique, we have identified a number of proteins that show increased expression levels in malignant breast tissues such as casein kinase Ie, p53, annexin XI, CDC25C, eIF-4E and MAP kinase 7. The expression of other proteins, such as the multifunctional regulator 14-3-3e was found to be decreased in malignant breast tissue, whereas the majority of proteins remained unchanged when compared to the corresponding non-malignant samples. The protein expression pattern was confirmed by immunohistochemistry, in which antibodies against 8 representative proteins known to be involved in carcinogenesis were employed in paraffin-embedded normal and malignant tissue sections deriving from the same patient. In each case, the results obtained by IHC matched the data obtained by antibody microarray system. Taken together, we have described for the first time a tumor cell specificity protein expression pattern by use of a novel commercially available antibody microarray system. We have thus demonstrated the feasibility of high-throughput protein arrays in the proteomic analysis of human breast tissue. We hypothesize that the use of protein arrays will not only increase our understanding of the molecular events, but could prove useful in evaluating prognosis and in determining optimal antineoplastic therapy.

Background: Tumour necrosis factor-alpha (TNF-alpha) is a potent cytokine secreted primarily by activated cells from the monocyte/macrophage lineage which exhibits various antitumoral effects including the induction of apoptosis, necrosis, activation of lytic effector cells as well as upregulation of the expression of intercellular adhesion molecule-1 (ICAM-1) which is of decisive importance in the interaction with lymphokine activated killer cells. Previous studies from our laboratory have indicated impaired production of TNF-alpha by monocytes as well as decreased expression of ICAM-1 on monocytes derived from patients with various stages of breast cancer., Methods: In the present experiments, we have assessed spontaneous as well as lipopolysaccharide (LPS)-induced production of TNF-alpha by as well as expression of ICAM-1 on monocytes derived from healthy females with germline mutations of BRCA1 and from healthy age-matched control females., Results: We report that monocytes derived from healthy women with various germline mutations of BRCA1 had significantly decreased spontaneous (p = 0.03) and LPS-induced (p < 0.001) production of TNF-alpha, as compared to monocytes derived from healthy age-matched control females. In contrast, no difference in LPS- or TNF-alpha-induced production of interleukin-6 was found. Whereas unstimulated monocytes derived from healthy women with germline mutations of BRCA1 and from healthy control women had similar expression of ICAM-1, stimulation with cytokines TNF-alpha and/or interleukin-1 led to a significant increase of ICAM-1 expression on monocytes derived from control females only, but not from BRCA1 germline mutation carriers (p < 0.001)., Conclusion: We conclude that the presence of germline mutations of BRCA1 was associated with a selective deficiency in spontaneous and LPS-induced production of TNF-alpha and of TNF-alpha-induced ICAM-1 expression on peripheral blood monocytes.

Over-expression of members of the ErbB-receptor family has been associated with malignant transformation. The amplification of Her-2/neu in tumor tissue is now an established prognostic factor in breast cancer. In order to initiate signal transduction, ErbB-receptor monomers need to form homo- or heterodimers. The composition of these dimers is thought to influence both quality and quantity of downstream signaling pathways, and to determine the biological response. We have investigated the protein expression pattern of the four ErbB-receptors EGFR, Her-2/neu, Her-3 and Her-4, and correlated it with their putative ligands EGF, TGF-alpha and HRG in 74 women with invasive breast cancer. Using western blot-analysis on cell membrane isolates, we detected the co-expression of all four ErbB-family members in 79.7% of cases, and of all of the three investigated ligands in 82.4%. We did not observe a correlation between EGFR and Her-2/neu or Her-4 protein expression, EGFR and Her-3 (p = 0.005), and Her-3 and Her-4 (p = 0.05) were clearly co-expressed. The strongest overall correlation, was found between Her-2/neu and Her-3 (p < 0.001) and between Her-2/neu and Her-4 (p = 0.001). This was particularly true in nodal-positive tumors (p < 0.001 and p = 0.002) whereas in nodal-negative tumors the co-expression was either less significant (Her-2/neu and Her-3; p = 0.01) or not significant (Her-2/neu and Her-4). The co-expression of EGFR/Her-3 was associated with the expression of all ligands, whereas the Her-2/neu/Her-3 was correlated with HRG (p = 0.002), thereby indicating a functional relation between specific receptor-dimer combinations and putative ligands. Taken together, we have performed the first comprehensive survey of ErbB-system expression in breast cancer, and have demonstrated the presence of a co-regulated receptor/ligand system in vivo. We have further shown that Her-2/neu is the preferred co-expression partner in nodal-positive tumors and thus the most likely dimerization candidate in malignant breast tumors.

The differential expression pattern of estrogen receptor alpha (ER-alpha), estrogen receptor beta (ER-beta) and their co-activator/co-repressor proteins is thought to modulate estrogenic action and to be present already during the early stages of tumorigenesis. It has therefore been postulated that certain co-activator and co-repressor proteins contribute to the development of breast cancer. There are some reports providing information on gene amplification and mRNA over-expression of certain co-factors in breast cancer, but to date there is only limited knowledge about their respective protein expressions. The aim of this study was to examine the expression of four steroid receptor co-activators (steroid receptor co-activator 1 (SRC-1), transcription intermediary factor 2 (TIF 2), protein 300 kDa/CREB binding protein (p300/CBP), amplified in breast cancer 1 (AIB1)), and of the co-repressor nuclear receptor co-repressor (NCoR), in malignant breast tissues and in matching normal breast biopsies of the same individuals. Protein expression was analyzed by immunohistochemistry and was compared to prognostic parameters such as lymph node involvement, tumor grading and receptor status. All members of the co-regulatory protein family were detected in both, benign and matching malignant tissue samples, except for AIB1, which was found to be expressed exclusively in malignant epithelium. AIB1 was preferentially present in carcinomas with high tumor grade (r = 0.48, p = 0.014), and was co-expressed with p300/CBP (r = 0.54, p = 0.006). TIF 2 correlated significantly to nodal status (r = 0.46, p = 0.025). Furthermore, protein levels of ER-beta p300/CBP and AIB1 were higher in invasive ductal carcinomas than in normal mammary tissue. The tumoral ER-alpha protein expression was significantly correlated with that of PgR (r = 0.61, p = 0.001) and NCoR (r = 0.4, p = 0.043), whereas ER-beta expression was associated with SRC-1 (r = 0.68, p < or = .001), TIF 2 (r = 0.64, p = 0.001) and NCoR (r = 0.48, p = 0.014) protein levels in malignant specimens. In our hands, 20% of ER-beta positive tumors did not express ER-alpha protein, thereby suggesting that a substantial fraction of ER-beta positive tumors is falsely considered to be 'estrogen receptor negative' if only ER-alpha specific antibodies are employed in the histological assessment of the ER status.

Tissue remodeling is a key element in the local invasion and metastasis of malignant breast tumors. The degradation of extracellular matrix that is associated with this process is thought to be mediated by a number of Zn2+-dependent matrix metalloproteinases (MMPs). In most cases these enzymes are not produced by the malignant epithelium itself but by adjacent breast stroma, suggesting an important role for cell-cell interactions. We have analyzed Gelatinase A (MMP-2) and Gelatinase B (MMP-9) gene expression in a panel of six breast cancer cell lines and six primary cultures of stromal cells deriving from breast cancer biopsies. With one exception we did not detect MMP-2 or MMP-9 gene expression in any of the established tumor cell lines. Conversely, tumor stroma-derived fibroblasts expressed MMP-2 mRNA. although no MMP-9 mRNA was seen in RNase protection assays. When fibroblasts were cultured in the presence of media conditioned by MCF-7 tumor cells, MMP-2 enzyme production increased but MMP-9 activity remained undetectable. However, when fibroblasts and MCF-7 tumor cells were co-cultured together, MMP-9 was induced. These observations were confirmed by immunocytochemical analysis of co-cultures of MCF-7 and tumor-derived fibroblasts in which MMP-2 and MMP-9 protein expression was confined to stromal cells adjacent to MCF-7 tumor cells. No MMP-2 or MMP-9 staining was detected in monocultures of the two respective cell types. We conclude that MMP-2 expression is present in the stroma of malignant tumors and is increased by paracrine stimulation mediated by soluble factors. In contrast, MMP-9 expression tumor-derived fibroblasts requires direct contact with malignant tumor epithelium.

Seroma formation after axillary lymphadenectomy in women with breast cancer remains a problem despite many efforts to reduce surgery-related morbidity. In a prospective, randomised, open, parallel-group, controlled clinical trial we evaluated the effect of a fibrin-glue coated collagen patch (TachoComb H, Nycomed Pharma AS, Denmark) on volume and duration of postoperative axillary drainage, duration of hospital stay, and procedural safety. Sixty patients were included in the study. Patients did not differ with respect to general characteristics, such as age, body mass index, treatment modality, and tumor stage distribution. In 29 patients, a fibrin-glue coated collagen patch was applied from the apex axillae to the thoracic longus nerve and half a patch was applied to the lateral border of the axillary nerve-vessel bundle. Thirty-one patients were randomised to standard closure of the axillary lymphadenectomy area. The mean duration of axillary drainage was 3.8 +/- 1.9 days in the fibrin-glue treatment group and 3.9 +/- 1.8 days in the control group (p = NS). The mean total drainage volume was 338.5 +/- 251.8 ml in the fibrin-glue treatment group and 370.8 +/- 314.6 ml in the standard closure group (p = NS). The mean length of post-operative hospital stay was 9.1 +/- 2.7 days in the fibrin-glue treatment group and 9.3 +/- 3.6 days in the standard closure group (p = NS). Seven patients (25%) and eight patients (25%) were diagnosed with local inflammation in the fibrin-glue treatment group and the standard closure group, respectively (p = NS). Seroma formation after drain removal was found in 11 patients (39%) in the fibrin-glue treatment group and in 13 patients (42%) in the standard closure group (p = NS). In summary, we observed no statistically significant differences with respect to axillary drainage time, drainage volume, length of hospital stay, local inflammation, and seroma formation after drainage removal.

Breast function and development are controlled by a variety of both local and systemic signals. Many of these signals are exerted by hormones and cytokines which are believed to be effectors in autoregulatory feedback loops. Recent studies have also suggested the involvement of such mechanisms in human breast cancer. For example, the disruption of a negative feedback system by malignant transformation can result in the loss of growth control or in increased malignant behavior of tumor cells. Conversely, pathological positive feedback loops can develop that enhance tumor growth and invasion by excessive release of stimulatory factors. These loops are often located at the site of tumor invasion and involve stromal-epithelial interactions. They can be composed of mutually stimulating or inhibiting cytokines and may include locally expressed sex steroids. Although most studies have concentrated on cell-cell interactions at the site of the primary tumor, a number of observations indicate their importance in metastases as well. A thorough analysis of the regulatory mechanisms within a malignant tumor is essential for the understanding of its unique behavior and for the investigation of more specific breast cancer therapies.

Purpose: To assess the value of 99m-Tc-tetrofosmin (tetrofosmin) scintigraphy in patients with palpable and nonpalpable breast lesions., Patients and Methods: Prospective, blinded trial. One hundred and fifty-nine consecutive patients with 163 breast lesions detected by clinical examination and mammography were included. Tetrofosmin scintigraphy of the breast was performed additionally to the regular diagnostic procedure. Using histologic assessment as the golden standard, sensitivity, specificity, positive and negative predictive value for tetrofosmin scintigraphy of the breast were assessed., Results: Overall sensitivity and specificity were 82% and 84%. The sensitivity for palpable tumors (65%) was 93% compared to 62% for non-palpable breast lesions. Malignant lesions were nearly twice as big as benign lesions (31.5 mm +/- 2.4 vs. 16.9 mm +/- 2.4). Specificity, positive and negative predictive value (84%, 89%, and 66%) did not differ significantly in palpable versus non-palpable tumors. Of malignant tumors 18% were found false negative by tetrofosmin scintigraphy., Conclusion: The results suggest that tetrofosmin scintigraphy is a valuable tool for the evaluation of palpable breast cancer. In patients with non-palpable tumors, tetrofosmin scintigraphy may not add to the work-up of patients with breast cancer due to a low sensitivity rate.

The paraffin sections from 20 nipples with Paget's disease (10 central intraductal and 10 invasive ductal carcinomas) were analyzed for human papilloma virus (HPV) DNA of the low- and intermediate/high-risk groups. Polymerase chain reaction (PCR) and dot (slot) blot hybridization were used for the detection of HPV DNA types 6/11/16/18/31/33/35. In addition, we examined the c-erbB-2 oncogene expression in the specimens to differentiate benign cells in the surface epithelium of the nipple and areola from Paget cells. We found that the oncogene expression of the c-erbB-2 displayed a strong signal in the Paget cells. Using PCR and dot (slot) blot hybridization, we could not detect the HPV DNAs that are specific for the low- and intermediate/high risk-groups in the 20 cases of Paget's disease. Our results showed for the first time that this type of virus did not contribute to the pathogenesis of Paget's disease.