Search

Background: The monarchE and NATALEE trials demonstrated the benefit of CDK4/6 inhibitor (CDK4/6i) therapy in adjuvant breast cancer (BC) treatment. Patient selection, based on clinical characteristics, delineated those at high (monarchE) and high/intermediate recurrence risk (NATALEE). This study employed a historical patient cohort to describe the proportion and prognosis of patients eligible for adjuvant CDK4/6i trials., Methods: Between 2009 and 2011, 3529 patients were enrolled in the adjuvant PreFace clinical trial (NCT01908556). Eligibility criteria included postmenopausal patients with hormone receptor-positive (HRpos) BC for whom a five-year upfront therapy with letrozole was indicated. Patients were categorized into prognostic groups according to monarchE and NATALEE inclusion criteria, and their invasive disease-free survival (iDFS) and overall survival (OS) were assessed., Results: Among 2891 HRpos patients, 384 (13.3 %) met the primary monarchE inclusion criteria. The majority (n = 261) qualified due to having ≥ 4 positive lymph nodes. For NATALEE, 915 out of 2886 patients (31.7 %) met the eligibility criteria, with 126 patients (13.7 %) being node-negative. Patients from monarchE with ≥ 4 positive lymph nodes and NATALEE with stage III BC exhibited the poorest prognosis (3-year iDFS rate 0.87). Patients ineligible for the trials demonstrated prognoses similar to the most favorable patient groups within the eligibility criteria., Conclusion: Patient populations eligible for monarchE and NATALEE trials differed. Nearly a third of the postmenopausal HRpos population, previously under upfront letrozole treatment, met the NATALEE prognostic eligibility criteria. As certain eligible groups had a prognosis similar to non-eligible patients, it might be interesting to explore additional patient groups for CDK4/6i therapy., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: P.A.F. reports grants from Biontech and Cepheid, personal fees from Novartis, Pfizer, Daiichi Sankyo, AstraZeneca, Eisai, MSD, Lilly, Pierre Fabre, SeaGen, Roche, Hexal, Agendia, Gilead. C.C.H. received honoraria from AstraZeneca, Daiichi Sankyo, Eisai, Novartis, Pfizer, Roche, Gilead and MSD, and travel grants from Daiichi-Sankyo. N.N. is an employee of Novartis Pharma GmbH. B.A. received honoraria from AstraZeneca, Gilead, Genomic Health, Roche, Novartis, Celgene, Lilly, MSD, Eisai, Stemline, Teva, Tesaro, Daiichi Sankyo and Pfizer. Received travel grants from AstraZeneca, Roche, Novartis, Celgene, Lilly, Eisai, Stemline, Daiichi Sankyo and Pfizer. Participated in the data safety monitoring board or advisory boards for AstraZeneca, Gilead, Genomic Health, Roche, Novartis, Celgene, Lilly, MSD, Eisai, Tesaro, Daiichi Sankyo and Pfizer. S.K. received honoraria from Amgen, Celgene, Daiichi Sankyo, Novartis and Roche. C.T. received honoraria for advisory boards and lectures from Amgen, AstraZeneca, Celgene, Daiichi Sankyo, Eisai, Gilead, Lilly, MSD, Mylan, Nanostring, Novartis, Pfizer, Pierre Fabre, Puma, Roche, Seagen, Vifor. H.-C.K. received honoraria from Pfizer, Novartis, Roche, Genomic Health/Exact Sciences, Amgen, AstraZeneca, Riemser, Carl Zeiss Meditec, TEVA, Theraclion, Janssen-Cilag, GSK, LIV Pharma, Lilly, Daiichi Sankyo, Gilead and Zuellig, travel support from Carl Zeiss Meditec, LIV Pharma, Novartis, Amgen, Pfizer, Daiichi Sankyo, Tesaro, Gilead, AstraZeneca, Zuellig, and Stemline, participated in data safety monitoring or advisory boards for Pfizer, Novartis, SurgVision, Carl Zeiss Meditec, Amgen, Onkowissen, MSD, Gilead, Daiichi Sankyo, Seagen, Genomic Health/Exact Sciences, Agendia, Lilly and owns stock of Theraclion SA. W.J. has received research grants and/or honoraria from Sanofi-Aventis, Daiichi Sankyo, Novartis, Roche, Pfizer, Lilly, AstraZeneca, Chugai, GSK, Eisai, Celgene and Johnson&Johnson. A.S. reported grants from Celgene, Roche and AbbVie. Personal fees from Celgene, Roche, Pfizer, AstraZeneca, Novartis, MSD, Tesaro, Lilly, Seagen, Gilead, GSK, Bayer, Amgen, and Pierre Fabre, and travel grants from Celgene, Roche, Pfizer and AstraZeneca. F.M. received honoraria from Amgen, AstraZeneca, Celgene, Clovis Oncology, CureVac, Eisai, Genomic Health, GSK, Immunomedics, Janssen-Cilag, Lilly, MSD, Novartis, Pfizer, PharmaMar, Roche, Seattle Genetics, Tesaro. M.W.S. received honoraria from AstraZeneca, Pfizer, Clovis, Mylan, Roche, Gedeon Richter, Carl Zeiss Meditec, travel support from Pfizer, Carl Zeiss Meditec. C.J. reports personal fees from AstraZeneca, Exact Sciences, Lilly, Novartis and Roche. V.M. received speaker honoraria from AstraZeneca, Daiichi Sankyo, Eisai, Pfizer, MSD, Medac, Novartis, Roche, Seagen, Onkowissen, high5 Oncology, Medscape, Gilead, Pierre Fabre, iMED Institut. Consultancy honoraria: Roche, Pierre Fabre, PINK, ClinSol, Novartis, MSD, Daiichi Sankyo, Eisai, Lilly, Seagen, Gilead, Stemline. Institutional research support from Novartis, Roche, Seagen, Genentech, AstraZeneca. Travel grants from AstraZeneca, Roche, Pfizer, Daiichi Sankyo, Gilead. C.R. received honoraria from MSD and AstraZeneca, travel expenses from the Swiss Society of Senology and the Swiss Society of Gynecology. P.D. received honoraria from MSD, Pierre Fabre, Novartis, AstraZeneca, Lilly, Gilead, Pfizer, Roche. E.B. received honoraria from Novartis, Hexal, BMS, Lilly, Pfizer, Roche, MSD, Bayer, Ipsen, Bluebird, B. Braun and onkowissen.de for consulting, clinical research management or medical education activities. S.Y.B. has received honoraria from Roche Pharma, Novartis, Pfizer, MSD, Teva, AstraZeneca. T.N.F. has received honoraria from Novartis, Roche, Pfizer, TEVA, Diachii Sankyo, AstraZeneca and MSD. All of the remaining authors have declared that they do not have any conflicts of interest., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Importance: The increasing use of neoadjuvant systemic therapy (NST) has led to substantial pathological complete response rates in patients with initially node-positive, early breast cancer, thereby questioning the need for axillary lymph node dissection (ALND). Targeted axillary dissection (TAD) is feasible for axillary staging; however, data on oncological safety are scarce., Objective: To assess 3-year clinical outcomes in patients with node-positive breast cancer who underwent TAD alone or TAD with ALND., Design, Setting, and Participants: The SenTa study is a prospective registry study and was conducted between January 2017 and October 2018. The registry includes 50 study centers in Germany. Patients with clinically node-positive breast cancer underwent clipping of the most suspicious lymph node (LN) before NST. After NST, the marked LNs and sentinel LNs were excised (TAD) followed by ALND according to the clinician's choice. Patients who did not undergo TAD were excluded. Data analysis was performed in April 2022 after 43 months of follow-up., Exposure: TAD alone vs TAD with ALND., Main Outcomes and Measures: Three-year clinical outcomes were evaluated., Results: Of 199 female patients, the median (IQR) age was 52 (45-60) years. A total of 182 patients (91.5%) had 1 to 3 suspicious LNs; 119 received TAD alone and 80 received TAD with ALND. Unadjusted invasive disease-free survival was 82.4% (95% CI, 71.5-89.4) in the TAD with ALND group and 91.2% (95% CI, 84.2-95.1) in the TAD alone group (P = .04); axillary recurrence rates were 1.4% (95% CI, 0-54.8) and 1.8% (95% CI, 0-36.4), respectively (P = .56). Adjusted multivariate Cox regression indicated that TAD alone was not associated with an increased risk of recurrence (hazard ratio [HR], 0.83; 95% CI, 0.34-2.05; P = .69) or death (HR, 1.07; 95% CI, 0.31-3.70; P = .91). Similar results were obtained for 152 patients with clinically node-negative breast cancer after NST (invasive disease-free survival: HR, 1.26; 95% CI, 0.27-5.87; P = .77; overall survival: HR, 0.81; 95% CI, 0.15-3.83; P = .74)., Conclusions and Relevance: These results suggest that TAD alone in patients with mostly good clinical response to NST and at least 3 TAD LNs may confer survival outcomes and recurrence rates similar to TAD with ALND.

Purpose: Phosphatidylinositide-3-kinase (PI3K) regulates proliferation and apoptosis; somatic PIK3CA-mutations may activate these processes. Aim of this study was to determine the prevalence of PIK3CA-mutations in a cohort of early stage breast cancer patients and the association to the course of disease., Patients and Methods: From an unselected cohort of 1270 breast cancer patients (PiA, Prognostic Assessment in routine application, NCT01592825) 1123 tumours were tested for the three PIK3CA hotspot-mutations H1047R, E545K, and E542K by qPCR. Primary objectives were the prevalence of somatic PIK3CA-mutations and their association to tumour characteristics. Secondary objective was the association of PIK3CA-mutations to recurrence-free interval (RFI) and overall survival., Results: PIK3CA-mutation rate was 26.7% (300 of 1123). PIK3CA-mutations were significantly more frequent in steroid hormone-receptor (SHR)-positive HER2-negative (31.4%), and G1 and G2 tumours (32.8%). Overall, we did not observe a significant association of PIK3CA-mutations to RFI. In SHR-positive BCs with PIK3CA-mutations, a strong trend for impaired  RFI was observed (adjusted HR 1.64, 95% CI 0.958-2.807), whilst in SHR-negative BCs PIK3CA-mutations were insignificantly associated with improved RFI (adjusted HR 0.49; 95% CI 0.152-1.597). Of note, we observed a significantly detrimental prognostic impact of PIK3CA-mutations on RFI in SHR-positive, HER2-negative BCs if only aromatase inhibitors were administered as adjuvant therapy (adjusted HR 4.44, 95% CI 1.385-13.920), whilst no impact was observed in tamoxifen treated patients., Conclusion: This cohort study speficies the overall mutation rate of PIK3CA in early breast cancer. The impact of PIK3CA-mutations on RFI and OS was heterogeneous. Our results suggest that estrogen deprivation failes to be active in case of PIK3CA-mutation., (© 2022. The Author(s).)

Objective: This study aimed to investigate the feasibility and accuracy of non-radioactive TLN biopsy and TAD in routine clinical practice., Background Data: TAD involves TLN biopsy (TLNB) and sentinel lymph node biopsy and was recently introduced as a new standard for less invasive axillary staging in BC patients undergoing neoadjuvant systemic therapy (NST); however, clinical evidence is limited., Methods: The SenTa study is a prospective registry study conducted at 50 centers. Patients with invasive BC who nderwent clip insertion into the most suspicious axillary lymph node were eligible. Axillary surgery was performed with or without sentinel lymph node biopsy, TLNB, and/or axillary lymph node dissection (ALND). Main endpoints were the detection rate and FNR of TLNB and TAD after NST., Results: Between 2017 and 2018, 548 consecutive BC patients underwent clip placement into biopsy-confirmed positive lymph nodes. After NST (n = 473), the clipped TLN was intraoperatively resected in 329 of 423 patients [77.8%, 95% confidence interval (CI): 74.0-82.0]. TAD was successful in 199 of 229 patients (detection rate: 86.9%, 95% CI: 81.8-91.0), the SLN and TLN were identical in 129 patient (64.8%). FNRs were 7.2% (8 of 111, 95% CI: 3.1-13.6) for TLNB followed by ALND (n = 203) and 4.3% (2 of 46, 95% CI: 0.5-14.8) for TAD followed by ALND (n = 77)., Conclusions: The SenTa study demonstrates the feasibility of TAD in a real-world cohort of BC patients. Our findings are of great importance for de-escalation of surgical strategies., Competing Interests: S. Kuemmel reports personal fees from Somatex, during the conduct of the study; personal fees from Roche/Genentech, Genomic Health, Lilly, Novartis, Amgen, Celgene, Daiichi Sankyo, Astra Zeneca, Somatex, MSD, Pfizer, Püma Biotechnology, PFM medical, non-financial support from Roche, Daiichi Sankyo, Somatex, and Sonoscape outside the submitted work. J. Heil reports non-financial support from Somatex, during the conduct of the study; non-financial support from BARD and pfm medical, personal fees from Siemens and Roche, outside the submitted work. C. Ankel reports personal fees from PMF medicals, grants from Sebbin, outside the submitted work. P. Dall reports personal fees from Roche Pharma, Novartis, Astra Zeneca, Pfizer, Eisai, Amgen, Hexal, Genomic Health, outside the submitted work. T. Kuehn reports personal fees from Roche and Pfizer, travel expenses from Celgene, SABCS, outside the submitted work. J.-U. Blohmer reports personal fees from Amgen, Astra Zeneca, MSD, Novartis, Pfizer, Roche, and Sonoscape, travel expenses from Roche and Pfizer, outside the submitted work. A. Kostara reports personal fees from Astra Zeneca, travel expenses from Tessaro, MSD, Somatex, outside the submitted work. E. Breit reports personal fees from Sysmex, Olympus, Merck Serono, and Daiichi Sankyo, outside the submitted work. J. Holtschmidtreports personal fees and non-financial support from Roche Pharma, non-financial support from PharmaMar, personal fees from Merck Sharp Dome and Hologic, outside the submitted work. M. Reinisch reports personal fees from Somatex, during the conduct of the study, personal fees and other from Novartis, personal fees and other from Pfizer, personal fees from MSD, AstraZeneca, Roche, and Lilly, other from Celgene, outside the submitted work. The authors report no conflicts of interest., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Breast cancer tumors are known to be highly heterogeneous and differences in their metabolic phenotypes, especially at protein level, are less well-understood. Profiling of metabolism-related proteins harbors the potential to establish new patient stratification regimes and biomarkers promoting individualized therapy. In our study, we aimed to examine the relationship between metabolism-associated protein expression profiles and clinicopathological characteristics in a large cohort of breast cancer patients., Methods: Breast cancer specimens from 801 consecutive patients, diagnosed between 2009 and 2011, were investigated using reverse phase protein arrays (RPPA). Patients were treated in accordance with national guidelines in five certified German breast centers. To obtain quantitative expression data, 37 antibodies detecting proteins relevant to cancer metabolism, were applied. Hierarchical cluster analysis and individual target characterization were performed. Clustering results and individual protein expression patterns were associated with clinical data. The Kaplan-Meier method was used to estimate survival functions. Univariate and multivariate Cox regression models were applied to assess the impact of protein expression and other clinicopathological features on survival., Results: We identified three metabolic clusters of breast cancer, which do not reflect the receptor-defined subtypes, but are significantly correlated with overall survival (OS, p ≤ 0.03) and recurrence-free survival (RFS, p ≤ 0.01). Furthermore, univariate and multivariate analysis of individual protein expression profiles demonstrated the central role of serine hydroxymethyltransferase 2 (SHMT2) and amino acid transporter ASCT2 (SLC1A5) as independent prognostic factors in breast cancer patients. High SHMT2 protein expression was significantly correlated with poor OS (hazard ratio (HR) = 1.53, 95% confidence interval (CI) = 1.10-2.12, p ≤ 0.01) and RFS (HR = 1.54, 95% CI = 1.16-2.04, p ≤ 0.01). High protein expression of ASCT2 was significantly correlated with poor RFS (HR = 1.31, 95% CI = 1.01-1.71, p ≤ 0.05)., Conclusions: Our data confirm the heterogeneity of breast tumors at a functional proteomic level and dissects the relationship between metabolism-related proteins, pathological features and patient survival. These observations highlight the importance of SHMT2 and ASCT2 as valuable individual prognostic markers and potential targets for personalized breast cancer therapy., Trial Registration: ClinicalTrials.gov, NCT01592825 . Registered on 3 May 2012.

Background: The objective of this prospectively randomized phase II trial (Trial registration: EUCTR2004-004007-37-DE) was to compare the clinical response of primary breast cancer patients to neoadjuvant therapy with letrozole alone (LET) or letrozole and zoledronic acid (LET + ZOL)., Methods: Patients were randomly assigned to receive either LET 2.5 mg/day (n = 79) or the combination of LET 2.5 mg/day and a total of seven infusions of ZOL 4 mg every 4 weeks (n = 89) for 6 months. Primary endpoint was clinical response rate as assessed by mammogram readings. The study was terminated prematurely due to insufficient recruitment. We report here on an exploratory analysis of this data., Results: Central assessment of tumor sizes during the treatment period was available for 131 patients (66 LET, 65 LET + ZOL). Clinical responses (complete or partial) were seen in 54.5% (95% CI: 41.8-66.9) of the patients in the LET arm and 69.2% (95% CI: 56.6-80.1) of those in the LET + ZOL arm (P = 0.106). A multivariate model showed an OR of 1.72 (95% CI: 0.83-3.59) for the experimental arm., Conclusion: No increase in the clinical response rate was observed with the addition of ZOL to a neoadjuvant treatment regimen with LET. However a trend towards a better reponse in the LET + ZOL arm could be observed. This trend is consistent with previous studies that have investigated the addition of ZOL to chemotherapy, and it may support the evidence for a direct antitumor action of zoledronic acid.

Background: Today, more than 70% of patients with primary node-negative breast cancer are cured by local therapy alone. Many patients receive overtreatment by adjuvant chemotherapy due to inadequate risk assessment. So far, few clinical trials have prospectively evaluated tumor biology based prognostic factors. Risk assessment by a biological algorithm including invasion factors urokinase-type plasminogen activator (uPA) and its inhibitor plasminogen activator inhibitor type 1 (PAI-1) will assess up to 35-55% of node-negative patients as low-risk and thus avoid chemotherapy. In contrast, a clinical-pathological algorithm will only classify 20-40% of patients as low-risk. High-risk node-negative patients should receive chemotherapy. Anthracycline-based regimens are accepted as a standard, the additional benefit of taxanes remains an open question., Methods/design: The international NNBC3 ("Node Negative Breast Cancer 3-Europe") trial compares biological risk assessment (UP) using invasion factors uPA/PAI-1 with a clinical-pathological algorithm (CP). In this trial, the type of risk assessment (CP or UP) was chosen upfront by each center for its patients. Fresh frozen tissue was obtained to determine uPA/PAI-1 using an enzyme-linked immunosorbent assay (ELISA). Patients assessed as high-risk were stratified by human epidermal growth factor receptor 2 (HER2) status and then randomised to receive anthracycline-containing chemotherapy 5-Fluorouracil (F)/Epirubicin (E)/Cyclophosphymide (C) or an anthracycline-taxane sequence (FE(100)C*6 versus FE(100)C*3 followed by Docetaxel(100)*3)., Discussion: In this trial, 4,149 node-negative patients with operable breast cancer from 153 centers in Germany and France were included since 2002. Measurement of uPA/PAI-1 by ELISA was performed with standardised central quality assurance for 2,497 patients (60%) from 56 "UP"-centers. The NNBC 3-Europe trial showed that inclusion of patients into a clinical phase III trial is feasible based on biological testing of fresh frozen tumor material. In addition, 2,661 patients were classified as high-risk and thus received chemotherapy. As adjuvant chemotherapy, 1,334 high-risk patients received FE(100)C-Docetaxel(100), and 1,327 received French FE(100)C. No unexpected toxicities were observed. Chemotherapy efficacy and comparison of UP with CP will be evaluated after longer follow-up., Trial Registration: clinical Trials.gov NCT01222052., (© 2011 Kantelhardt et al; licensee BioMed Central Ltd.)

Background: Increasing effort has been put in the implementation and certification of breast centers in order to establish standardized, quality assured health care for breast cancer patients. The aim of this analysis was to investigate whether patients treated in certified breast centers (CBC) have a favorable prognosis as compared to patients treated outside of certified breast treatment units., Patients and Methods: The data of 3,940 patients with invasive nonmetastatic breast cancer were analyzed with regard to differences in patient and tumor characteristics and crude overall survival according to diagnosis in or outside CBC in Middle Franconia, Germany. Patient, tumor, and follow-up data were obtained from the clinical cancer registry., Results: Patients in CBC were younger, and had lower disease stages and lower grading. Independent of the effects of these variables on overall survival, being treated at a CBC added to the prediction of overall survival. Patients treated at a CBC had a hazard ratio of 0.70 (95% confidence interval 0.52-0.93) in the adjusted Cox model., Conclusions: Independent from common prognostic factors, diagnosis and treatment of breast cancer at a CBC improves the prognosis of patients. It can be hypothesized that this effect is mediated through quality assured health care provided by the certification process., (Copyright © 2011 S. Karger AG, Basel.)

The growth of estrogen-receptor positive breast cancer cells is inhibited by the pineal gland hormone, melatonin. Concern has been raised that power-line frequency and microwave electromagnetic fields (EMFs) could reduce the efficiency of melatonin on breast cancer cells. In this study we investigated the impact of EMFs on the signal transduction of the high-affinity receptor MT1 in parental MCF-7 cells and MCF-7 cells transfected with the MT1 gene. The binding of the cAMP-responsive element binding (CREB) protein to a promoter sequence of BRCA-1 after stimulation with melatonin was analyzed by a gel-shift assay and the expression of four estrogen-responsive genes was measured in sham-exposed breast cancer cells and cells exposed to a sinusoidal 50 Hz EMF of 1.2 microT for 48 h. In sham-exposed cells, binding of CREB to the promoter of BRCA-1 was increased by estradiol and subsequently diminished by treatment with melatonin. In cells exposed to 1.2 microT, 50 Hz EMF, binding of CREB was almost completely omitted. Expression of BRCA-1, p53, p21(WAF), and c-myc was increased by estradiol stimulation and subsequently decreased by melatonin treatment in both cell lines, except for p53 expression in the transfected cell line, thereby proving the antiestrogenic effect of melatonin at molecular level. In contrast, in breast cancer cells transfected with MT1 exposed to 1.2 microT of the 50 Hz EMF, the expression of p53 and c-myc increased significantly after melatonin treatment but for p21(WAF) the increase was not significant. These results convincingly prove the negative effect of EMF on the antiestrogenic effect of melatonin in breast cancer cells., ((c) 2009 Wiley-Liss, Inc.)

Melatonin possesses anti-estrogenic effects on estrogen receptor expressing (ER+) breast cancer cells in culture by reducing cell cycle progression and cell proliferation. There is increasing agreement that on a cellular level the effects of melatonin are primarily induced by the membrane-bound receptor MT1. The participation of a second, nuclear receptor of the group of ligand-dependent transcription factors, called RZRalpha, is under debate. In this study we used a number of breast cancer cell lines differing in their expression of the estrogen receptor and the two known melatonin receptors. In MCF-7 breast cancer cells transfected with a vector carrying the MT1 gene (MCF-7Mel1a) binding of CREB-protein to the cAMP-responsive element of the breast cancer suppressing gene BRCA-1 was more strongly reduced by treatment with melatonin than in the parental cells. Expression of estrogen responsive genes was determined in serum-starved cells, cells stimulated for 16 hr with estradiol and cells subsequently treated with melatonin. Expression of BRCA-1, p53, p21(WAF) and c-myc were up-regulated by estradiol. Treatment of the stimulated cells with melatonin counteracted the increase induced by estradiol almost completely. The more MT1 a cell line expressed, the stronger was the reduction of the expression of the estradiol-induced genes. There was no correlation between the expression of the nuclear receptor RZRalpha and the effects of melatonin on these genes.

Breast cancer is the most common malignancy of women in Western societies. The increasing exposure to electromagnetic fields has been suspected to contribute to the rising incidence of breast cancer in industrialized countries. The majority of breast tumors is treated with the partial antiestrogen tamoxifen. Most tumors become resistant to tamoxifen in the course of treatment resulting in treatment failure. Electromagnetic fields reduce the efficacy of tamoxifen similar to tamoxifen resistance. In this study we investigated the mechanism by which electromagnetic fields influence the sensitivity to tamoxifen. In cells exposed to 1.2 microT of a 50 Hz electromagnetic field gene expression of cofactors of the estrogen receptors was compared to sham exposed cells. Using a gene array technology several cofactors were found to be differentially expressed. The expression of the coactivators, SRC-1 and AIB1, and of two corepressors, N-Cor and SMRT, was quantified by RT-PCR. Both coactivators were expressed more strongly in the exposed cells while the expression of two corepressors decreased. The RNA analysis was confirmed by Western blots. The contradirectional changes in gene expression of coactivators and corepressors by electromagnetic fields results in a lower sensitivity to tamoxifen. Electromagnetic fields may contribute to the induction of tamoxifen resistance in vivo., ((c) 2007 Wiley-Liss, Inc.)

Worldwide, each year approximately one million women are newly diagnosed with breast cancer (BC), in Germany 65 new cases per 100,000 inhabitants are registered, yearly. The fact that incidence has been rising in parallel with economic development indicates that environmental factors might play a role in the causation of BC. Migrational data have pointed to nutrition as one of the more relevant external factors involved. Preventive dietary advice often includes a reduction of alcohol, red meat and animal fat and increasing the intake of vegetables, fruit and fibre and lately, phyto-estrogens from various sources. Clearly, the scientific basis for these recommendations appears sparse. The available prospective data from epidemiological studies and interventional trials do not support the overall hypothesis that higher fat-intakes are a relevant risk factor for BC development, more important seems the relative distribution of various fatty acids. A non-vegetarian eating habit (consumption of animal products) per se does not elevate BC risk, while consumption of broiled or deep fried meats cannot be ruled out as a risk factor in genetically susceptible individuals. It appears prudent to abstain from regular and increased alcohol consumption. This should be particularly true for pubescent girls, in whom glandular breast tissue is particularly vulnerable. In general, if alcohol is consumed on a regular basis, a sufficient supply of fresh vegetables and fruit is essential. While there is no overall protective effect of a high fruit and vegetable consumption speculation remains over possible beneficial effects of certain subcategories, especially brassica vegetables like broccoli, cauliflower and cabbage. In essence, regional differences in BC incidence are probably partially attributable to life long dietary habits. There is no need to adopt a foreign dietary plan in order to protect oneself against BC. Traditional western diets also have their beneficial ingredients that should be regular constituents in our meals. Lignans from traditionally made sourdough rye bread, linseed/flaxseed and berries are local sources of potentially canceroprotective phyto-estrogens. Furthermore, indole-3-carbinol rich cabbage species might contribute to BC protection by diet. Nevertheless, clear cut recommendations for or against single nutrients or secondary plant metabolites are not yet possible, lacking sufficient data on individual bioavailability, safety and long term outcome. BC prevention by dietary means therefore relies on an individually tailored mixed diet, rich in basic foods and traditional manufacturing and cooking methods.

Background: Breast cancer is the most frequent solid tumor in women. The incidence is increasing. In Germany, about 45,000 women are newly diagnosed each year. The general strategy aims for the best local control of the tumor by surgery and radiotherapy. This strategy is supplemented by systemic adjuvant chemotherapy and/or anti-hormonal therapy. The following substances have shown their efficacy in clinical trials: alkylating agents, antimetabolites, anthracyclines, topoisomerase inhibitors, platinum derivatives, and taxanes. Due to intensified treatment schedules remission rates and overall survival could be significantly improved. On the other hand, the long-term toxicity of this antineoplastic therapy is an increasing problem., Secondary Leukemias: Therapy-associated secondary leukemias frequently occur after treatment for malignant lymphomas and multiple myelomas. However, they can also be observed after antineoplastic therapy of solid tumors such as cancers of the breast, lung, testicles and ovaries and sarcomas. The highest risk for secondary leukemias has been attributed to concurrent radiochemotherapy. Therapy-associated hematologic neoplasias are a severe medical problem due to the high incidence of breast cancer and the dismal outcome of secondary leukemias, which occur in 0.3-5% of patients receiving antineoplastic therapy., Risk Factors: The delineation of new individual risk factors is urgently required to improve the safety of modern breast cancer treatment, which includes intensive combined radiochemotherapy. Candidate mechanisms could be polymorphisms in DNA repair and/or xenobiotic-metabolizing enzymes. Preliminary data suggest that the resulting deficiencies in xenobiotic-metabolizing enzymes such as glutathione S-transferases increase the risk for therapy-induced hematologic neoplasias in patients with breast cancer.

Objectives: Detection of the antiestrogenic effect of melatonin on various breast cancer cell lines and its dependence of the differential expression of estrogen receptors (ERalpha and ERbeta) and melatonin receptors (mt1 and RZRalpha)., Setting and Design: Dose-response curves of estradiol were determined in 6 different breast cancer cell lines using a colorimetric proliferation assay in the absence or presence of various melatonin concentrations., Methods: In order to detect the minor growth inhibitory effect of melatonin, a simple yet novel approach was employed: instead of incubating cells at single estradiol-concentrations at increasing melatonin levels, breast cancer cells were grown in microwell-plates for 4 days at increasing concentrations of estradiol (10(-12)M - 10(-10)M) in the absence or presence of melatonin (10(-9)M - 10(-8)M). Cell number was determined using Alamar blue and colorimetry. RT-PCR was performed for the expression of ERalpha, ERbeta, RZRalpha and mt1., Results: Melatonin at concentrations of 10(-9)M and 5 x 10(-9)M shifted the dose-response curves of estradiol to higher concentrations. Responsiveness to melatonin depended on expression of ERalpha but not on ERbeta. mRNA of ERbeta was not detectable in the breast cancer cell lines used. Only small amounts of mt1 transcripts were detectable in MCF-7 cells of one source. In MCF-7 cells transfected with the mt1 gene and in an ovarian cancer cell line mt1 was expressed at significant levels. RZRalpha was expressed in all tested cell lines at different amounts., Conclusion: The growth of all ERalpha-positive breast cancer cell lines can be inhibited by melatonin. The effect in most cell lines is weak yet clearly reproducible. RZRalpha clearly contributes to the growth inhibitory effect of melatonin.