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Breast cancer is still the most common type of cancer in women; an important role in carcinogenesis is actually attributed to cancer-associated fibroblasts. In this study, we investigated whether it is possible to assess the functional state of cancer-associated fibroblasts through tumor tissue proteome profiling. Tissue proteomics was performed on tumor-central, tumor-near, and tumor-distant biopsy sections from breast adenocarcinoma patients, which allowed us to identify 2074 proteins. Data were interpreted referring to reference proteome profiles generated from primary human mammary fibroblasts comprising 4095 proteins. These cells were analyzed in quiescent cell state as well as after in vitro treatment with TGFβ or IL-1β, stimulating wound healing or inflammatory processes, respectively. Representative for cancer cells, we investigated the mammary carcinoma cell line ZR-75-1, identifying 5212 proteins. All mass analysis data have been made fully accessible via ProteomeXchange, DOI PXD001311 and PXD001323-8. Comparison of tissue proteomics data with all of those reference profiles revealed predominance of cancer cell-derived proteins within the tumor and fibroblast-derived proteins in the tumor-distant tissue sections. Remarkably, proteins characteristic for acute inflammation were hardly identified in the tissue samples. In contrast, several proteins found by us to be induced by TGFβ in mammary fibroblasts, including fibulin-5, SLC2A1, and MUC18, were positively identified in all tissue samples, with relatively higher abundance in tumor neighboring tissue sections. These findings indicate a predominance of cancer-associated fibroblasts with wound healing activities localized around tumors.

Single Nucleotide Polymorphisms (SNPs) in genes involved in the DNA Base Excision Repair (BER) pathway could be associated with cancer risk in carriers of mutations in the high-penetrance susceptibility genes BRCA1 and BRCA2, given the relation of synthetic lethality that exists between one of the components of the BER pathway, PARP1 (poly ADP ribose polymerase), and both BRCA1 and BRCA2. In the present study, we have performed a comprehensive analysis of 18 genes involved in BER using a tagging SNP approach in a large series of BRCA1 and BRCA2 mutation carriers. 144 SNPs were analyzed in a two stage study involving 23,463 carriers from the CIMBA consortium (the Consortium of Investigators of Modifiers of BRCA1 and BRCA2). Eleven SNPs showed evidence of association with breast and/or ovarian cancer at p<0.05 in the combined analysis. Four of the five genes for which strongest evidence of association was observed were DNA glycosylases. The strongest evidence was for rs1466785 in the NEIL2 (endonuclease VIII-like 2) gene (HR: 1.09, 95% CI (1.03-1.16), p = 2.7 × 10(-3)) for association with breast cancer risk in BRCA2 mutation carriers, and rs2304277 in the OGG1 (8-guanine DNA glycosylase) gene, with ovarian cancer risk in BRCA1 mutation carriers (HR: 1.12 95%CI: 1.03-1.21, p = 4.8 × 10(-3)). DNA glycosylases involved in the first steps of the BER pathway may be associated with cancer risk in BRCA1/2 mutation carriers and should be more comprehensively studied.

Background: Tuberin, the protein product of tuberous sclerosis gene 2 (TSC2), is the functional component of the TSC1/TSC2 complex and regulates cell cycle through activation of the cyclin-dependent kinase inhibitor p27. The transcriptional regulation of p27 is, however, also linked to a functional BRCA protein, since in BRCA1 mutant breast cancer cells, which lack the ability to repair DNA damages by homologous recombination, p27 is down-regulated. We have therefore investigated the expression of both tuberin and p27 in normal breast tissue, and in malignant epithelium from women with and without a BRCA mutation., Materials and Methods: immunohistochemistry was used to compare p27 and tuberin protein expression in 26 BRCA1 and 2 mutation carriers, in 53 matched breast cancer patients without a family history, and in 74 benign breast tissues in a case-control study., Results: Tuberin and p27 protein expression were significantly more common in benign when compared to malignant breast tissue (p = 0.01 and p = 0.03), but no difference was observed when sporadic and BRCA-mutated breast cancer specimen were compared. Tuberin and p27 were positively correlated with each other (p = 0.0017, r = 0.2527). Furthermore, p27 expression was positively correlated with ER and PR, and negatively correlated with tumor size. The expression of tuberin and p27 in breast cancer was not correlated with clinical outcome., Conclusion: Our results suggest that tuberin and p27 are aberrantly expressed in malignant tissue, but their expression does not appear to be dependent on the BRCA mutation state of a breast cancer patient.

Although the use of (neo-)adjuvant chemotherapy in breast cancer patients has resulted in improved outcome, not all patients benefit equally. We have evaluated the utility of an in vitro chemosensitivity assay in predicting response to neoadjuvant chemotherapy. Pre-therapeutic biopsies were obtained from 30 breast cancer patients assigned to neoadjuvant epirubicin 75 mg/m2 and docetaxel 75 mg/m2 (Epi/Doc) in a prospectively randomized clinical trial. Biopsies were subjected to a standardized ATP-based Epi/Doc chemosensitivity assay, and to gene expression profiling. Patients then received 3 cycles of chemotherapy, and response was evaluated by changes in tumor diameter and Ki67 expression. The efficacy of Epi/Doc in vitro was correlated with differential changes in tumor cell proliferation in response to Epi/Doc in vivo (p = 0.0011; r = 0.73670, Spearmańs rho), but did not predict for changes in tumor size. While a pre-therapeutic gene expression signature identified tumors with a clinical response to Epi/Doc, no such signature could be found for tumors that responded to Epi/Doc in vitro, or tumors in which Epi/Doc exerted an antiproliferative effect in vivo. This is the first prospective clinical trial to demonstrate the utility of a standardized in vitro chemosensitivity assay in predicting the individual biological response to chemotherapy in breast cancer.

Common genetic variants contribute to the observed variation in breast cancer risk for BRCA2 mutation carriers; those known to date have all been found through population-based genome-wide association studies (GWAS). To comprehensively identify breast cancer risk modifying loci for BRCA2 mutation carriers, we conducted a deep replication of an ongoing GWAS discovery study. Using the ranked P-values of the breast cancer associations with the imputed genotype of 1.4 M SNPs, 19,029 SNPs were selected and designed for inclusion on a custom Illumina array that included a total of 211,155 SNPs as part of a multi-consortial project. DNA samples from 3,881 breast cancer affected and 4,330 unaffected BRCA2 mutation carriers from 47 studies belonging to the Consortium of Investigators of Modifiers of BRCA1/2 were genotyped and available for analysis. We replicated previously reported breast cancer susceptibility alleles in these BRCA2 mutation carriers and for several regions (including FGFR2, MAP3K1, CDKN2A/B, and PTHLH) identified SNPs that have stronger evidence of association than those previously published. We also identified a novel susceptibility allele at 6p24 that was inversely associated with risk in BRCA2 mutation carriers (rs9348512; per allele HR = 0.85, 95% CI 0.80-0.90, P = 3.9 × 10(-8)). This SNP was not associated with breast cancer risk either in the general population or in BRCA1 mutation carriers. The locus lies within a region containing TFAP2A, which encodes a transcriptional activation protein that interacts with several tumor suppressor genes. This report identifies the first breast cancer risk locus specific to a BRCA2 mutation background. This comprehensive update of novel and previously reported breast cancer susceptibility loci contributes to the establishment of a panel of SNPs that modify breast cancer risk in BRCA2 mutation carriers. This panel may have clinical utility for women with BRCA2 mutations weighing options for medical prevention of breast cancer., Competing Interests: The authors have declared that no competing interests exist.

Background: In an aging population an increasing number of breast cancers is diagnosed in elderly women. Tumor characteristics and patterns of metastasation have been extensively elucidated in younger triple negative breast cancer (TNBC) patients, but data regarding TNBC in elderly women are missing. The goal of this investigation was to compare clinical pathological characteristics of younger and elderly TNBC patients in order to assess their relevance for TNBC in an aging population., Methods: Data of TNBC patients diagnosed between 1998 and 2004 were retrospectively analyzed by computer based chart information. Baseline tumor characteristics, patient demographics and patterns of metastasation were compared between younger (<65 years) and elderly (≥65 years) TNBC patients., Results: Out of 254 TNBC patients 75.6% were <65 years and 24.4% were ≥65 years. Mean tumor size, tumor grade and number of positive lymph nodes did not differ significantly (p=0.865, 0.115 and 0.442, respectively) between both age groups. Distant visceral metastases occurred significantly more often than bone metastases in both age groups (p<0.001). Local recurrences, bone and secondary lymph node metastases were observed at significantly higher numbers in younger patients (p=0.035, 0.025 and 0.041, respectively). Elderly TNBC patients received significantly less chemotherapy than younger patients (p<0.001)., Conclusions: TNBC of elderly patients is an aggressive breast cancer subtype claiming as much attention as TNBC in younger patients, thus warranting chemotherapeutic intervention irrespectively of age., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Germline mutations in BRCA1 and BRCA2 are associated with increased risks of breast and ovarian cancer. A genome-wide association study (GWAS) identified six alleles associated with risk of ovarian cancer for women in the general population. We evaluated four of these loci as potential modifiers of ovarian cancer risk for BRCA1 and BRCA2 mutation carriers. Four single-nucleotide polymorphisms (SNPs), rs10088218 (at 8q24), rs2665390 (at 3q25), rs717852 (at 2q31), and rs9303542 (at 17q21), were genotyped in 12,599 BRCA1 and 7,132 BRCA2 carriers, including 2,678 ovarian cancer cases. Associations were evaluated within a retrospective cohort approach. All four loci were associated with ovarian cancer risk in BRCA2 carriers; rs10088218 per-allele hazard ratio (HR) = 0.81 (95% CI: 0.67-0.98) P-trend = 0.033, rs2665390 HR = 1.48 (95% CI: 1.21-1.83) P-trend = 1.8 × 10(-4), rs717852 HR = 1.25 (95% CI: 1.10-1.42) P-trend = 6.6 × 10(-4), rs9303542 HR = 1.16 (95% CI: 1.02-1.33) P-trend = 0.026. Two loci were associated with ovarian cancer risk in BRCA1 carriers; rs10088218 per-allele HR = 0.89 (95% CI: 0.81-0.99) P-trend = 0.029, rs2665390 HR = 1.25 (95% CI: 1.10-1.42) P-trend = 6.1 × 10(-4). The HR estimates for the remaining loci were consistent with odds ratio estimates for the general population. The identification of multiple loci modifying ovarian cancer risk may be useful for counseling women with BRCA1 and BRCA2 mutations regarding their risk of ovarian cancer., (© 2012 Wiley Periodicals, Inc.)

Background: BRCA-1/2 germline mutations are responsible for early onset breast cancer and familial association. The underlying causes of the characteristic phenotypic behavior are not completely understood, but mammary stem cells appear to have a key role in this process., Materials and Methods: We have investigated the presence of mammary stem / progenitor cells in normal tissues and in tumor tissues obtained from women with and without BRCA1/2 germline mutations by utilizing ALDH-1 immunohistochemistry., Results: Isolated ALDH-1 positive cells were found in 15/28 (54%) of breast cancer samples from women with BRCA 1 or 2 mutations and in 33 /51 (65%) of matched sporadic breast cancer cases (p=0.5949, Chi Square test). While mammary stem cells were also detected in non-malignant breast lesions, only 41% of the tissues contained ALDH-1 positive cells (p=0.0371, Chi Square test). In patients with BRCA germline mutations ALDH-1 positive cells were more common in p53 positive (p=0.0028, Chi Square test) tumors, in high grade (p=0.0796), and in larger tumors (p=0.0604), while no such association was seen in sporadic cancer cases. In our patients, the expression of ALDH-1 positive cells in breast cancer was neither associated with disease-free and overall survival, nor time to metastasis., Conclusion: Breast cancers from BRCA mutation carriers do not harbor more ALHD-1 positive cells than sporadic tumors, and their more aggressive phenotype can thus not be explained by an increased stem cell pool. The presence of ALDH-1 in normal breast tissue suggests that additional factors determine the biological behavior of mammary stem cells.

Background: BRCA1 and BRCA2 mutation carriers have a lifetime breast cancer risk of 40% to 80%, suggesting the presence of risk modifiers. We previously identified significant associations in genetic variants in the insulin-like growth factor (IGF) signaling pathway. Here, we investigate additional IGF signaling genes as risk modifiers for breast cancer development in BRCA carriers., Methods: A cohort of 1,019 BRCA1 and 500 BRCA2 mutation carriers were genotyped for 99 single-nucleotide polymorphisms (SNP) in 13 genes. Proportional hazards regression was used to model time from birth to diagnosis of breast cancer for BRCA1 and BRCA2 carriers separately. For linkage disequilibrium (LD) blocks with multiple SNPs, an additive genetic model was used. For an SNP analysis, no additivity assumptions were made., Results: Significant associations were found between risk of breast cancer and LD blocks in IGF2 for BRCA1 and BRCA2 mutation carriers (global P values of 0.009 for BRCA1 and 0.007 for BRCA2), HTRA1 for BRCA1 carriers (global P value of 0.005), and MMP3 for BRCA2 carriers (global P = 0.0000007 for BRCA2)., Conclusions: We identified significant associations of genetic variants involved in IGF signaling. With the known interaction of BRCA1 and IGF signaling and the loss of PTEN in a majority of BRCA1 tumors, this suggests that signaling through AKT may modify breast cancer risk in BRCA1 carriers., Impact: These results suggest potential avenues for future research targeting the IGF signaling pathway in modifying risk in BRCA1and BRCA2 mutation carriers., (©2011 AACR.)

Purpose: Aromatase inhibitors are effective as endocrine treatment for patients with hormone receptor-positive breast cancer. According to the hypothesis that overweight patients have higher levels of aromatase enzyme availability, we investigated the influence of body mass index (BMI) on the efficacy of adjuvant endocrine therapy in premenopausal patients in a retrospective analysis of the Austrian Breast and Colorectal Cancer Study Group (ABCSG) 12 trial., Patients and Methods: ABCSG-12 examined the efficacy of ovarian suppression using goserelin (3.6 mg subcutaneously every 28 days) in combination with anastrozole or tamoxifen with or without zoledronic acid (4 mg intravenously every 6 months) in premenopausal women with endocrine-responsive breast cancer. BMI was calculated using the prospectively collected data on patients' height and weight at study entry. BMI categories have been differentiated according to the WHO definition., Results: Overweight patients treated with anastrozole had a 60% increase in the risk of disease recurrence (hazard ratio [HR], 1.60; 95% CI, 1.06 to 2.41; P = .02) and more than a doubling in the risk of death (HR, 2.14; 95% CI, 1.17 to 3.92; P = .01) compared with normal weight patients treated with anastrozole. In the overweight group, patients treated with anastrozole had a nearly 50% increase in the risk of disease recurrence (HR, 1.49; 95% CI, 0.93 to 2.38; P = .08) and a three-fold increase in the risk of death (HR, 3.03; 95% CI, 1.35 to 6.82; P = .004) compared with patients treated with tamoxifen., Conclusion: BMI significantly impacts on the efficacy of anastrozole plus goserelin in premenopausal patients with breast cancer, probably through influencing aromatase availability and/or ovarian suppression by goserelin.

Background: Immunomagnetic EpCAM based methods are used to enrich circulating tumor cells (CTCs) in metastatic breast cancer (mBC) patients. EpCAM negative CTCs may be missed. We addressed the question of the reliability of an EpCAM dependent assay to enrich CTCs., Methods: To elucidate this issue, our study has been designed to assess two different CTC enrichment technologies (i) in EpCAM positive (+) and EpCAM negative cell lines and (ii) in mBC patients in dependency on their respective EpCAM expression. These two technologies encompass one anti-EpCAM immunomagnetic enrichment technology, MACS HEA MicroBeads(®) (MACS), and one EpCAM independent density centrifugation method, OncoQuick(®) plus (OQ+). Furthermore, the coherence between EpCAM expression in the primary tumor tissue of mBC patients and the CTC detection rates in the corresponding patients is analyzed., Results: (i) MACS recovered significantly more EpCAM (+) than EpCAM (-) tumor cells (p < 0.001) in spiked blood samples. With OQ+ no significantly different recovery rates between EpCAM (+) and EpCAM (-) tumor cells (p = 0.796) were detected. (ii) In mBC patients MACS yielded a significantly higher (p = 0.024) detection rate of EpCAM (+) CTCs. No statistically significant difference (p = 0.070) was found concerning the EpCAM status-based detection rate of CTCs by OQ+. (iii) CTC detection rates are independent of the primary tumors' EpCAM expression., Conclusions: EpCAM (-) CTCs can not be detected by immunomagnetic EpCAM dependent enrichment methods. EpCAM independent enrichment technologies seem to be superior to detect the entire CTC population. Evaluation of CTCs as prognostic marker should compromise EpCAM (+) and (-) subpopulations.

An adjuvant chemotherapeutic standard has not been identified in triple negative breast cancer (TNBC) yet. One hundred and forty-one adjuvant treated TNBC patients had a median follow-up of 71 months. Larger tumor size (p = .005) and positive lymph-node status (p = .033) were associated with a significant shorter overall survival. Sixty-one percent of patients received anthracycline-containing chemotherapy, 28.4% a non-anthracycline-containing regimen, and 10.6% an anthracycline/taxane-containing regimen. Overall survival, disease-free survival, local recurrence-free survival and distant disease-free survival did not differ between the chemotherapeutic groups. Non-anthracycline-containing regimen appeared to be an effective treatment in TNBC.

Comprehensive in vitro and in vivo studies comparing EpCAM-based methods with other cytometric CTC enrichment technologies in metastatic colorectal cancer (mCRC) patients are lacking. We compare four manual cytometric methods to detect CTCs in vitro and in mCRC patients. The EpCAM-based technology, MACS HEA MicroBeads((R)), showed a significant better tumor cell recovery rate compared to other cytometric methods (p-value<0.0001). CTCs of 38 mCRC patients were enriched with MACS HEA MicroBeads(R). Progression-free survival did significantly differ between mCRC patients without detectable and with >or= 1 CTCs (p=0.007). CTC enrichment with EpCAM coupled antibodies is superior to other cytometric methods and is a feasible method for CTC detection in mCRC patients.

Objective: Adiponectin serum levels have been shown to be inversely correlated with breast cancer risk. The protein is believed to act through adiponectin receptor 1 (AdipoR1) and has been suggested to play an important role in cancer development. While AdipoR1 is known to be expressed in invasive tumors, its role in DCIS remains elusive. We therefore investigated AdipoR1 expression in both invasive and preinvasive breast cancer., Methods: Tissue microarrays were established from paraffin-embedded archived tissues which contained 104 invasive breast cancers with adjacent preinvasive component (DCIS) as well as 96 preinvasive breast cancers. AdipoR1 expression was investigated by immunohistochemistry and correlated with clinical and tumor parameters., Results: AdipoR1 was detected in stromal and epithelial components of both invasive and preinvasive breast cancer. However, stromal and epithelial immunoreactivity for AdipoR1 was significantly higher in invasive breast cancer compared to preinvasive DCIS (p<0.001 and p=0.009). Within DCIS, AdipoR1 expression was inversely correlated with tumor size (r=-0.238, p=0.033). Menopausal status showed no influence on AdipoR1 expression., Conclusions: The altered expression of AdipoR1 in invasive breast cancer compared to DCIS suggests that the receptor-binding protein adiponectin might exert growth inhibitory effects that are overcome in transformation of preinvasive to invasive breast cancer., (Copyright 2009 Elsevier Inc. All rights reserved.)

Introduction: Current attempts to identify genetic modifiers of BRCA1 and BRCA2 associated risk have focused on a candidate gene approach, based on knowledge of gene functions, or the development of large genome-wide association studies. In this study, we evaluated 24 SNPs tagged to 14 candidate genes derived through a novel approach that analysed gene expression differences to prioritise candidate modifier genes for association studies., Methods: We successfully genotyped 24 SNPs in a cohort of up to 4,724 BRCA1 and 2,693 BRCA2 female mutation carriers from 15 study groups and assessed whether these variants were associated with risk of breast cancer in BRCA1 and BRCA2 mutation carriers., Results: SNPs in five of the 14 candidate genes showed evidence of association with breast cancer risk for BRCA1 or BRCA2 carriers (P < 0.05). Notably, the minor alleles of two SNPs (rs7166081 and rs3825977) in high linkage disequilibrium (r² = 0.77), located at the SMAD3 locus (15q22), were each associated with increased breast cancer risk for BRCA2 mutation carriers (relative risk = 1.25, 95% confidence interval = 1.07 to 1.45, P(trend) = 0.004; and relative risk = 1.20, 95% confidence interval = 1.03 to 1.40, P(trend) = 0.018)., Conclusions: This study provides evidence that the SMAD3 gene, which encodes a key regulatory protein in the transforming growth factor beta signalling pathway and is known to interact directly with BRCA2, may contribute to increased risk of breast cancer in BRCA2 mutation carriers. This finding suggests that genes with expression associated with BRCA1 and BRCA2 mutation status are enriched for the presence of common genetic modifiers of breast cancer risk in these populations.

Objective: Adipositas and insulin resistance are modifiable risk factors for breast cancer. Adiponectin seems to be an important linkage of these associations. In this study, we investigated the relationship between intratumoral adiponectin receptor expression and insulin resistance as well as intratumoral insulin/IGF receptor expression in breast cancer specimen., Methods: Breast cancer tissue and fasting serum were collected from 26 female patients. After microdissection of frozen samples, RNA was isolated and expression of insulin receptor, IGFR1, IGFR2, AdipoR1 and AdipoR2 was measured on mRNA level by means of real time RT-PCR. Fasting insulin, glucose and c-peptide serum levels were analysed by ELISA. Insulin resistance was calculated using the HOMA model., Results: We were able to confirm AdipoR1 and AdipoR2 expression, respectively, in breast cancer specimen. Actually, neither insulin serum level nor whole-body insulin resistance showed any effect on insulin/IGF or adiponectin receptor expression in breast cancer. A strong positive correlation between insulin as well as IGF1 receptor and AdipoR1, but not AdipoR2, expression could be observed. Interestingly, AdipoR2 expression significantly correlated with vascular and lymphovascular invasion of breast cancer., Conclusion: We propose a close relationship between the intratumoral insulin signalling system and AdipoR1 but not AdipoR2 expression. As AdipoR2 but not AdipoR1 expression seems to correlate with invasiveness, we assume different functions of the two adiponectin receptors in breast cancer.

Inherited BRCA1/2 mutations confer elevated ovarian cancer risk. Knowledge of factors that can improve ovarian cancer risk assessment in BRCA1/2 mutation carriers is important because no effective early detection for ovarian cancers exists. A cohort of 1,575 BRCA1 and 856 BRCA2 mutation carriers was used to evaluate haplotypes at ATM, BARD1, BRIP1, CTIP, MRE11, NBS1, RAD50, RAD51, and TOPBP1 in ovarian cancer risk. In BRCA1 carriers, no associations were observed with ATM, BARD1, CTIP, RAD50, RAD51, or TOPBP1. At BRIP1, an association was observed for one haplotype with a multiple testing corrected P (P(corr)) = 0.012, although no individual haplotype was significant. At MRE11, statistically significant associations were observed for one haplotype (P(corr) = 0.007). At NBS1, we observed a P(corr) = 0.024 for haplotypes. In BRCA2 carriers, no associations were observed with CTIP, NBS1, RAD50, or TOPBP1. Rare haplotypes at ATM (P(corr) = 0.044) and BARD1 (P(corr) = 0.012) were associated with ovarian cancer risk. At BRIP1, two common haplotypes were significantly associated with ovarian cancer risk (P(corr) = 0.011). At MRE11, we observed a significant haplotype association (P(corr) = 0.012), and at RAD51, one common haplotype was significantly associated with ovarian cancer risk (P(corr) = 0.026). Variants in genes that interact biologically withBRCA1 and/or BRCA2 may be associated with modified ovarian cancer risk in women who carry BRCA1/2 mutations.

Objectives: Tamoxifen is a partial ER antagonist that is highly effective in the treatment of receptor positive breast cancer. It significantly reduces recurrence and improves survival in both pre- and postmenopausal women. Unfortunately, many ER+ positive tumors progress despite tamoxifen treatment and until now, no possibility exists to prospectively identify tamoxifen-resistant tumors. It has been suggested that that in HER2 over-expressing tumors, cross-talk via activated HER2 receptors is a key mechanisms by which tumors become tamoxifen-resistant., Methods: We have therefore used immunohistochemistry to analyze the expression of HER2 and activated ptyr-1248 HER2 in 408 women of ER+, early breast cancer who had received at least 2 years of adjuvant tamoxifen. We then analyzed possible associations between HER2 and pHER2 expression, and prognostic parameters, and evaluated the effect of HER2 expression and survival., Results: With HER2 being positive in 12 of 208 (2.9%) of ER+ positive tumors, HER2 overexpression was found to be considerably less common in ER+ tumors than what has been thought previously. The majority of HER2 overexpressing tumors, however, also expressed the activated receptor form (r = 0.664; P < 0.0001). Both HER2 and pHER2 are moderately correlated with Grading (r = 0.138; P = 0.0052 and r = 0.118; P = 0.0241, respectively) and nodal involvement (r = 0.163; P = 0.0018 and r = 0.134; P = 0.016, respectively), but neither HER2 nor its activated form are significant predictors of RFS, DFS, or OS., Conclusions: Taken together, we have demonstrated that in ER+ breast cancer, the HER2 receptor is commonly activated, but its low prevalence in ER+ tumors does not render it a useful prognostic parameter in tamoxifen-treated patients.

Objective: Obesity increases breast cancer risk in post-menopausal women. This is, in part, due to elevated non-glandular aromatase activity, resulting in higher estradiol serum levels. We tested the hypothesis that obesity and menopausal status influence the intra-tumoral estrogen system of breast cancer tissue., Design: Breast cancer tissue and fasting serum were collected from 26 female patients. After microdissection of the frozen samples, RNA was isolated, and expression of estrogen receptor (ER)alpha, ERbeta1, ERbeta2, ERbeta5, CYP19 aromatase and steroid sulfatase was measured on mRNA level by means of real time RT-PCR. Fasting estradiol serum levels were analysed by ELISA., Results: Post-menopausal women older than 70 years exhibited a significantly higher expression both of steroid sulfatase and ERalpha than did pre-menopausal women younger than 50 years. We identified a significant positive correlation between body mass index (BMI) and lymphovascular/vascular invasion. A significant inverse correlation between ERalpha and ERbeta2 expression was identified in invasive breast cancer tissue irrespective of BMI or menopausal status., Conclusion: In conclusion, we report an association between menopausal status - but not BMI - and the intra-tumoral expression of steroid sulfatase and ERalpha. Our observation that BMI was associated with invasiveness supports the hypothesis that metabolic factors are able to affect essential features of breast cancer.

Introduction: The role of the b-HCG/LH/LH-R system in breast cancer is conflicting. Whereas some reports suggest a protective effect of b-HCG on breast epithelium, vitro studies implicate a role of b-HCG/LH-R in the development and growth of breast tumors., Material and Methods: In order to further investigate a possible involvement of b-HCG/LH-R in breast carcinogenesis, immunofluorescence analyses of b-HCG/LH-R expression was performed on 70 preinvasive and adjacent invasive breast cancer specimen using tissue microarrays (TMAs)., Results: In 37 preinvasive samples available for further analysis, b-HCG/LH-R was found in 8/37 samples (21.6%; weak, intermediate and strong staining in 4/37 (10.8%), 2/37 (5.4%) and 2/37 (5.4%). In contrast, b-HCG/LH-R expression was observed in 19/27 (70.4%) adjacent invasive specimen with weak, moderate and strong immunostaining in 10/27 (37.0%), 6/27 (22.2%) and 3/27 (11.1%), respectively. This was statistically significant when compared to preinvasive components (P = 0.001, Chi Square Test)., Conclusions: Based on the observation that b-HCG/LH-R was found to be selectively upregulated in invasive tumor components, we suggest that under certain circumstances, sensitivity of ductal cells to hormones that target b-HCG/LH-R could favour mammary carcinogenesis.

Objective: Statins may exert pleiotropic effects on insulin action that are still controversial. We assessed effects of high-dose simvastatin therapy on peripheral and hepatic insulin sensitivity, as well as on ectopic lipid deposition in patients with hypercholesterolemia and type 2 diabetes., Research Design and Methods: We performed a randomized, double-blind, placebo-controlled, single-center study. Twenty patients with type 2 diabetes received 80 mg simvastatin (BMI 29 +/- 4 kg/m2, age 55 +/- 6 years) or placebo (BMI 27 +/- 4 kg/m2, age 58 +/- 8 years) daily for 8 weeks and were compared with 10 healthy humans (control subjects; BMI 27 +/- 4 kg/m2, age 55 +/- 7 years). Euglycemic-hyperinsulinemic clamp tests combined with D-[6,6-d2]glucose infusion were used to assess insulin sensitivity (M) and endogenous glucose production (EGP). 1H magnetic resonance spectroscopy was used to quantify intramyocellular and hepatocellular lipids., Results: High-dose simvastatin treatment lowered plasma total and LDL cholesterol levels by approximately 33 and approximately 48% (P < 0.005) but did not affect M, intracellular lipid deposition in soleus and tibialis anterior muscles and liver, or basal and insulin-suppressed EGP. In simvastatin-treated patients, changes in LDL cholesterol related negatively to changes in M (r = -0.796, P < 0.01). Changes in fasting free fatty acids (FFAs) related negatively to changes in M (r = -0.840, P < 0.01) and positively to plasma retinol-binding protein-4 (r = 0.782, P = 0.008)., Conclusions: High-dose simvastatin treatment has no direct effects on whole-body or tissue-specific insulin action and ectopic lipid deposition. A reduction in plasma FFAs probably mediates alterations in insulin sensitivity in vivo.

Introduction: Women who carry mutations in BRCA1 and BRCA2 have a substantially increased risk of developing breast cancer as compared with the general population. However, risk estimates range from 20 to 80%, suggesting the presence of genetic and/or environmental risk modifiers. Based on extensive in vivo and in vitro studies, one important pathway for breast cancer pathogenesis may be the insulin-like growth factor (IGF) signaling pathway, which regulates both cellular proliferation and apoptosis. BRCA1 has been shown to directly interact with IGF signaling such that variants in this pathway may modify risk of cancer in women carrying BRCA mutations. In this study, we investigate the association of variants in genes involved in IGF signaling and risk of breast cancer in women who carry deleterious BRCA1 and BRCA2 mutations., Methods: A cohort of 1,665 adult, female mutation carriers, including 1,122 BRCA1 carriers (433 cases) and 543 BRCA2 carriers (238 cases) were genotyped for SNPs in IGF1, IGF1 receptor (IGF1R), IGF1 binding protein (IGFBP1, IGFBP2, IGFBP5), and IGF receptor substrate 1 (IRS1). Cox proportional hazards regression was used to model time from birth to diagnosis of breast cancer for BRCA1 and BRCA2 carriers separately. For linkage disequilibrium (LD) blocks with multiple SNPs, an additive genetic model was assumed; and for single SNP analyses, no additivity assumptions were made., Results: Among BRCA1 carriers, significant associations were found between risk of breast cancer and LD blocks in IGF1R (global P = 0.011 for LD block 2 and global P = 0.012 for LD block 11). Among BRCA2 carriers, an LD block in IGFBP2 (global P = 0.0145) was found to be associated with the time to breast cancer diagnosis. No significant LD block associations were found for the other investigated genes among BRCA1 and BRCA2 carriers., Conclusions: This is the first study to investigate the role of genetic variation in IGF signaling and breast cancer risk in women carrying deleterious mutations in BRCA1 and BRCA2. We identified significant associations in variants in IGF1R and IRS1 in BRCA1 carriers and in IGFBP2 in BRCA2 carriers. Although there is known to be interaction of BRCA1 and IGF signaling, further replication and identification of causal mechanisms are needed to better understand these associations.

An important mechanism of antitumoral targeted therapies is the induction of apoptosis in tumor cells. Tamoxifen and trastuzumab (Herceptin), respectively, are able to trigger apoptosis in human breast cancer cells. But, frequently altered apoptotic signal cascades, for instance through PTEN mutations, help tumor cells to escape antitumoral therapy. We studied to what extent the apoptotic effect of signal-transduction inhibitors is dependent on PTEN expression. PTEN expression was analysed by Western blot analysis in tumor cell lines of the breast (BT-474, MCF-7, MDA-MB-231), ovary (BG-1, SK-OV-3) and endometrium (Ishikawa, HEC-1A). Apoptotic effects of tamoxifen, trastuzumab, ZD1839 (Iressa) and different mitogen-activated protein kinase (MAP) inhibitors were measured after 24 h of treatment. Cellular apoptosis was determined by the detection of cytoplasmic histone-DNA complexes. The tested tumor cell lines exhibited a different PTEN expression, ranging from a high expression (ovarian cancer cell line BG-1 and BT-474 breast cancer cells) to a total absence of PTEN expression (endometrial Ishikawa cells). The apoptotic effect of receptor-targeting drugs (tamoxifen, trastuzumab, ZD1839) was dependent both on receptor expression and PTEN expression. When cells were treated with MAPK inhibitors, no correlation between PTEN expression and the apoptosis rate was observed. Our data underline the importance of PTEN expression regarding the induction of apoptosis through various targeted therapies.

Estrogen receptor (ER) beta1 and its splice variants are expressed both in ovary and ovarian cancer. We studied the role of ERbeta1 and two of its splice variants in regulation of gene expression, cellular proliferation, apoptosis, and migration of an ovarian cancer cell line. In this study, we transfected SK-OV-3 ovarian cancer cells with vectors coding for ERbeta1 or its splice variants ERbeta-delta125 and ERbeta-delta1256, and tested their response to estrogen and tamoxifen in comparison with the untransfected cells. Heterologous expression of ERbeta1, but not of the exon-deleted ERbeta variants resulted in notably slower cell growth of SK-OV-3 ovarian cancer cells, an effect accompanied by more than tenfold increase of cyclin-dependent kinase inhibitor p21(WAF1) transcript levels and a significant reduction of cyclin A2 mRNA levels. SK-OV-3 cells stably overexpressing ERbeta1 ligand independently also exhibited an increased apoptosis rate and a significantly decreased motility, an effect accompanied by upregulation of fibulin 1c. Our data demonstrate that ERbeta1, but not the exon-deleted isoforms tested exerts multiple antitumoral effects on SK-OV-3 ovarian cancer cells even in the absence of estradiol or functional ERalpha.

Long-term treatment with estradiol increases LH secretion from female gonadotrophs. The mechanisms are not fully clarified yet. Our previous data indicated that sexual steroids might affect late steps in GnRH signal transduction such as exocytosis. The secretion of hormones from neuroendocrine cells requires the merger of secretory vesicles with the plasma membrane. This regulated exocytosis is mediated by specific proteins, which are present in the pituitary gland. Here, we examined whether two of these crucial exocytotic proteins, SNAP-25 and munc-18, are affected by estradiol in female gonadotrophs. Female rat anterior pituitary cells and alphaT3-1 cells, derived from a murine immortalized gonadotroph cell line, were treated with 100 pM estradiol for 48 h. LH secretion of anterior pituitary cells, additionally stimulated with eight consecutive pulses of 1 nM GnRH for 15 min at an interval of 1 h, was determined by RIA. Gene expression was measured by quantitative RT-PCR and protein expression by immunoblotting. Additionally, quantitative RT-PCR was performed in single rat gonadotrophs to ascribe effects exclusively to intact gonadotrophs. Pulsatile GnRH enhanced the mRNA expression of SNAP-25 and munc-18 in accordance with the LH secretory response with the greatest increase at the third pulse of GnRH. Estradiol treatment further increased GnRH-induced LH secretion at all GnRH pulses. SNAP-25 gene expression was significantly decreased at the fifth GnRH pulse and unaffected at basal after 48 h of estradiol treatment. In contrast, munc-18 mRNA levels were not significantly affected by estradiol at different GnRH-pulses in mixed anterior pituitary cells, whereas munc-18 gene expression was significantly increased at basal. In alphaT3-1 cells and single gonadotrophs, long-term estradiol treatment significantly reduced SNAP-25 protein and gene expression. In contrast, the protein and gene expression of munc-18 was significantly enhanced in both alphaT3-1 cells and single gonadotrophs. In conclusion, munc-18 and SNAP-25 were oppositionally influenced by estradiol. The results suggest that estradiol modulates the expression of exocytotic proteins in gonadotrophs and thus affects LH secretion.

Estrogen receptor (ER) beta gene codes for different transcript variants resulting from alternative splicing. In this study, we report identification of the two novel human exon-skipped ERbeta transcript isoforms ERbetaDelta125 and ERbetaDelta1256 in MDA-MD-231 breast cancer cells. Both transcripts could also be detected in a variety of human tissues. We further report the results of an in vitro attempt to characterize their function in regulation of cell growth, motility, apoptosis and gene expression. COS-1 cells stably transfected with the novel ERbeta transcripts exhibited a notably slower growth even in the absence of estradiol when compared to vector-transfected control cells. Like ERbeta1, both novel ERbeta transcript isoforms raised the basal apoptosis rate of COS-1 cells in a ligand-independent manner. Whereas introduction of ERbetaDelta1256 notably increased the sensitivity of COS-1 cells towards lower concentrations of selective estrogen receptor modulator tamoxifen, presence of ERbeta1 and ERbetaDelta125 transcripts further weakened the growth-inhibitory effect of tamoxifen on this cell line. Furthermore, expression of ERbetaDelta1256 variant was demonstrated to reduce transcript levels of estrogen-responsive genes like cyclin A2, IGFBP-4 and fibulin 1c in COS-1 cells in a ligand-independent manner. Though we were not able to detect the predicted 29 and 34kDa proteins by means of western blot analysis, our data strongly suggest the biological functionality of both isoforms on molecular level. With this report increasing the multitude of existing ERbeta mRNA isoforms, we provide further evidence that their synthesis has to be considered as an important level of estrogen signaling.

Background: The fasting serum lipid profile [triglycerides (TGs), total cholesterol (TC), and LDL- and HDL-cholesterol (LDL-C and HDL-C)] is used to calculate lipid ratios (TC/HDL-C, LDL-C/HDL-C, TG/HDL-C) that allow identification of individuals at increased risk for cardiovascular disease. Because these individuals are also frequently insulin resistant, this study analyzed the relationships between lipid ratios and insulin sensitivity., Methods: In 132 obese [mean (SE) body mass index, 37.5 (0.6) kg/m(2)] outpatients without known diabetes mellitus, fasting serum lipid profiles and 75-g oral glucose tolerance tests were performed. Insulin sensitivity was assessed from surrogate estimates for fasting (QUICKI) and dynamic (OGIS) conditions., Results: After exclusion of other endocrine diseases (n = 35), the remaining patients were classified as glucose tolerant (n = 56), glucose intolerant (n = 22), or as having type 2 diabetes (n = 19). QUICKI and OGIS indicated severe insulin resistance in all individuals with type 2 diabetes and impaired glucose tolerance compared with glucose-tolerant individuals: QUICKI, glucose tolerant, 0.302 (0.002); glucose intolerant, 0.290 (0.002); type 2 diabetes, 0.281 (0.005); P <0.001; OGIS (mL . m(-2) . min(-1)), glucose tolerant, 343 (7), glucose intolerant, 293 (9); type 2 diabetes, 256 (12); P <0.001. Serum TG (P <0.005) and TG/HDL-C ratios (P <0.05) were increased in individuals with impaired glucose tolerance. TG/HDL-C ratios negatively correlated with QUICKI (r = -0.370; P < 0.001) and OGIS (r = -0.333; P < 0.005) in nondiabetic individuals (glucose tolerant plus glucose intolerant), but not in patients with type 2 diabetes (not significant)., Conclusions: This study demonstrates that the TG/HDL-C ratio positively correlates with insulin resistance in severely obese nondiabetic individuals.

Temperatures ranging from room temperature (20 degrees C) to 42 degrees C are generally not considered to have an activating effect on platelets. However, this assumption is not supported by clinical phenomena that result in hemostatic failure related to hypothermia. In this study, we investigated the effect of temperatures between room temperature (20 degrees C) and 42 degrees C on human blood platelets and found that room temperature causes marked activation of platelets. Major changes in platelet morphology were seen at 20 degrees C compared to resting platelets at 37 degrees C. Platelet morphology was investigated with noninvasive live cell techniques (light microscopy and dynamic and static light scattering), as well as with transmission and scanning electron microscopy. The changes in platelet morphology correlated with the expression of the activation marker, activated glycoprotein (GP) IIb-IIIa, measured by flow cytometry. Twenty-five percent to 30% of platelets expressed activated GPIIb-IIIa after exposure to 20 degrees C for 10 minutes. In the presence of serotonin re-uptake inhibitors, the serotonin content of platelets at 20 degrees C was twice that of resting platelets. In comparison, moderate heat shock conditions (42 degrees C for 10 minutes) caused no signs of platelet activation as indicated by the absence of morphological alterations, no expression of activated GPIIb-IIIa, and no changes in serotonin content. These results show that room temperature by itself significantly activates platelets and has an effect on the platelet serotonin content. This may contribute to both the functional lesion associated with 22 degrees C storage of platelets for transfusion and the in vivo hemostatic failure after hypothermia.