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Purpose: To show feasibility of laser ablation inductively coupled mass spectrometry (LA-ICPMS) for analysis of zinc content and concentration in breast cancer tissue and to correlate this with validated prognostic and predictive markers, i.e. histological grading and expression of steroid receptors (estrogen receptor, ER; progesterone receptor, PR) and human epidermal growth-factor receptor 2 (Her2). Methods: 28 samples of human invasive ductal breast cancer tissue were subclassified into groups of four different intrinsic subtypes according to the expression of ER, PR and Her2 by immunohistological staining and then analyzed for zinc content and distribution by LA-ICPMS applying a calibration technique based on spiked polyacrylamide gels. A correlation of zinc concentration with histological grading and molecular subtypes was analyzed. Results: Consistent with results of a pilot-study LA-ICPMS was feasible to show zinc accumulation in cancerous tissue, even more adjacent healthy stroma was with proportional increase of zinc. Zinc levels were most elevated in triple-positive (TPBC) and in triple-negative (TNB) breast cancers. Conclusion: LA-ICPMS was feasible to confirm a connection between zinc and grade of malignancy; furthermore, focusing on a correlation of zinc and intrinsic breast cancer subtypes, LA-ICPMS depicted an upwards trend of zinc for "high-risk-cancers" with highest levels in Her2-positive and in triple-negative (TNBC) disease. The currently uncommon alliance of clinicians and analytical chemists in basic research is most promising to exploit the full potential of diagnostic accuracy in the efforts to solve the enigma of breast cancer initiation and course of disease. [ABSTRACT FROM AUTHOR]

Reprogramming of the chromatin landscape is a critical component to the transcriptional response in breast cancer. Effects of sex hormones such as estrogens and progesterone have been well described to have a critical impact on breast cancer proliferation. However, the complex network of the chromatin landscape, enhancer regions and mode of function of steroid receptors (SRs) and other transcription factors (TFs), is an intricate web of signaling and functional processes that is still largely misunderstood at the mechanistic level. In this review, we describe what is currently known about the dynamic interplay between TFs with chromatin and the reprogramming of enhancer elements. Emphasis has been placed on characterizing the different modes of action of TFs in regulating enhancer activity, specifically, how different SRs target enhancer regions to reprogram chromatin in breast cancer cells. In addition, we discuss current techniques employed to study enhancer function at a genome-wide level. Further, we have noted recent advances in live cell imaging technology. These single-cell approaches enable the coupling of population-based assays with real-time studies to address many unsolved questions about SRs and chromatin dynamics in breast cancer. [ABSTRACT FROM AUTHOR]

"nBackground: Molecular biomarkers are valuable in evaluation the course of malignancies. In this study, the relationship be­tween HER2/neu, p53, steroid receptors and clinicopathological features of patients with breast cancer has been assessed."nMethods: Three hundred thirty nine women with a primary diagnosis of breast cancer from 2001 to 2006 were included. They were evaluated for tumor features. The content of the steroid hormone receptors and expression of HER2/neu and p53 was also examined by immunohistochemistry assay."nResults: From patients arrived at this study, 52%, 36%, 46.5% and 44% were positive for HER2/neu, p53, ER and PR respec­tively. No association was found between most of pairs. HER2/neu expression significantly related with grade (P= 0.016). P53 had considerable reverse relation with axillary lymph node involvement and primary distant metastasis (P= 0.010 and P= 0.023, respectively). A significant association was found between PR and lymph node involvement (P= 0.038)."nConclusion: This study present the pattern of prognostic biomarkers in breast cancer for the first time in northeast of Iran and suggests to conduct larger studies regarding other effective variables include demographic ones.

Introduction: Breast carcinoma (BC) is a heterogeneous disease, with distinctive molecular sub-types, influencing BC patients prognosis and therapeutic options. Androgen Receptor (AR) is a steroid nuclear receptor involved in complex signaling pathways, that are thought to play a role in cell proliferation. AR expression in relation to different molecular sub-types of BC is not clearly understood. Aim: The aim of this study was to evaluate the expression of AR in BC from Egyptian patients and correlate it with the standard clinico-pathologic variables, molecular sub-type of BC and the Overall Survival (OS). Materials and Methods: This retrospective study was conducted on 81 cases of BC from egyptian patients, stained immunohistochemically with AR. Chi-Square and Kaplan meyer tests were applied to study the correlation between AR expression and clinicopathologic variables and the OS of BC patients respectively. Results: Among studied BC cases, 37.04% were immunoreactive to AR. AR immunoreactivity was significantly corrrelated with older age (p=0.03), post-menopausal status (p=0.001), lower grade (p=0.003), the presence of in-situ component (p= 0.014), early stage of presentation (p=0.03) and good-moderate NPI (0.009). It was also correlated with Positive ER, negative HER-2/ neu, low Ki67 proliferation index and luminal A subtype. AR expression didn't correlate with the OS in the studied cases. Conclusion: AR was found to be related to favourable prognostic factors in BC but not to OS. It was particularly expressed in luminal A group and in significant proportion in Triple Negative Breast Carcinoma (TNBC), providing an opportunity for AR targeted therapy. [ABSTRACT FROM AUTHOR]

To identify new pathways of estrogen action and novel estrogen receptor α (ERα) biomodulators, we performed high throughput screening and used follow on assays and bioinformatics to identify small molecule ERα inhibitors with a novel mode of action. These studies led to identification of rapid extranuclear activation of the endoplasmic reticulum stress sensor, the unfolded protein response (UPR), as a new pathway of estrogen-ERα action. Moreover, increasing evidence indicates that the mechanism underlying anticipatory activation of the UPR is shared among steroid and peptide hormones and is conserved from insects to humans. It is likely that this newly unveiled extranuclear pathway is used by diverse mitogenic hormones to prepare cells for the increased protein folding load that will occur during subsequent cell proliferation. Demonstrating biological relevance, elevated expression of a UPR gene signature in ERα positive breast cancer is a powerful new prognostic marker tightly correlated with subsequent resistance to tamoxifen, tumor recurrence and poor survival. In addition, overexpression of epidermal growth factor receptor and HER2/neu is positively correlated with increased UPR activation in breast cancer. This review describes recent research that demonstrates the importance of anticipatory UPR activation in therapy resistant tumors and discusses a promising small molecule biomodulator that inhibits tumor growth by tuning this UPR signaling pathway. [ABSTRACT FROM AUTHOR]

Abstract: The progesterone receptor (PR) plays a key role in reproduction and is important in cancers of the reproductive tract. Current PR antagonists usually compete for progestin binding in the PR ligand-binding pocket and often exhibit cross-binding with other members of the steroid receptor family. Using stably transfected cells expressing reporter genes, a set of ∼150 theophylline analogues were screened for their ability to inhibit progesterone, estrogen, glucocorticoid and androgen signaling. The structure–activity studies presented here identify branched 8-alkylthio-6-thio-substitutions of theophylline as selective PR inhibitors. 6-Thio-8-(2-ethylbutyl)thiotheophylline (51), the most extensively studied derivative, does not act by competing with progestins for binding in the ligand-binding pocket of PR. It demonstrated the ability to inhibit the mouse mammary tumor virus (MMTV)-luciferase reporter and endogenous PR-regulated alkaline phosphatase activity in T47D breast cancer cells. Compound 51 is the lead member of a novel class of PR inhibitors that act outside the PR ligand-binding pocket, thus serving as a novel probe to investigate PR action and a lead for further development. [Copyright &y& Elsevier]

The role of hormone receptors as a prognostic and therapeutic tool in breast cancer is widely accepted. The frequency of nonreactivity of estrogen and progesterone receptors in breast cancer patients of India is much more common than in the West. This study was conducted with the aim of analysis of steroid receptor status in breast cancer with clinico-pathological characteristics from the northern hilly state of Himachal Pradesh, India located in the region of the Western Himalayas. Fifty five consecutive patients with the diagnosis of breast cancer were included in this study. Detailed clinical and histopathologic data was recorded in all cases. Estrogen receptor and progesterone receptor status was evaluated by immunohistochemistry. Chi-square test was used for statistical analysis. On immunohistochemical staining, 34.5% cases proved to be estrogen receptor positive and 36.4% cases progesterone receptor positive. The results in the present study documented low estrogen receptor and progesterone receptor positivity in breast cancer from this region of India. [ABSTRACT FROM AUTHOR]

The estrogen receptor α (ERα) is activated as a transcription factor by both estrogen and a large variety of other extracellular signals. The mechanisms of this ligand-independent activation, notably by cAMP signaling, are still largely unknown. We now close the gap in the signaling pathway between cAMP and ERα. Whereas the direct phosphorylation of ERα by the cAMP-activated protein kinase A (PKA) is dispensable, the phosphorylation of the coactivator-associated arginine methyltransferase 1 (CARM1) by PKA at a single serine is necessary and sufficient for direct binding to the unliganded hormone-binding domain (HBD) of ERα, and the interaction is necessary for cAMP activation of ERα. Sustained PKA activity promoting a constitutive interaction may contribute to tamoxifen resistance of breast tumors. Binding and activation involve a novel regulatory groove of the ERα HBD. As a result, depending on the activating signal, ERα recruits different coactivator complexes to regulate alternate sets of target genes. [ABSTRACT FROM AUTHOR]

Summary: Inflammatory mammary carcinoma (IMC) is the most aggressive type of mammary tumour in the dog and has been proposed as a model for human inflammatory breast cancer. The aim of this study was to investigate angiogenesis in canine IMC by immunohistochemical assessment of the expression of vascular endothelial growth factor (VEGF). Tissues from 19 cases of IMC were compared with tissues from 27 cases of invasive mammary carcinoma without inflammation (non-IMC). Immunohistochemical expression of oestrogen receptor (ER), progesterone receptor (PR) and HER-2 receptor was also assessed. VEGF was strongly expressed in all IMCs and the percentage of VEGF-immunoreactive tumour cells was significantly higher in IMC than in non-IMC (P =0.02). There was no difference in HER-2 receptor expression between IMC and non-IMC, and no IMC expressed ER or PR. These results suggest that VEGF may contribute to the high angiogenic phenotype of canine IMC and that this expression may underlie the tendency towards local and systemic metastasis of these tumours. [Copyright &y& Elsevier]

Besides typing and grading of breast cancer, pathologists are involved in the determination of biomarkers, such as steroid hormone receptors and HER2, which are of utmost importance in adjuvant therapy. There have been concerns with regard to security and reproducibility of the biomarker assays done on tissue sections applying either immunohistochemistry or in-situ hybridisation. In order to assure the quality of these biomarker assays, a number of measures are required, among them external proficiency testing. Therefore, external quality assurance trials have been implemented in Germany. In the period of 2002–2007, 5 consecutive trials were conducted with up to 180 participating laboratories. Tissue microarrays with 20–24 different breast cancer samples including cell lines enabled that a huge number of pathologists were challenged with identical samples which provides the prerequisite for comparability. Because there is no legal duress to undergo external proficiency testing in histopathology, all laboratories that took part volunteered to do so. These innovative quality assurance trials (Qualitätsinitiative Pathologie, QuIP) will be continued in the future on an annual or bi-annual basis. Participation is recommended for pathology departments involved in the service for breast units. The organisational frame work of the trials is described here. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Individualization and optimization of risk-adapted therapy in breast cancer requires molecular profiling of individual cancer specimens. In tissues of heterogeneous cellular composition, such as mammary tissue, cancer prognostic markers and potential therapeutic target molecules are preferentially detected by in situ techniques such as immunohistochemistry. The more therapy decisions are based on immunohistochemical findings, the more histopathologists are confronted with the demand to establish standardized procedures that enable reproducible evaluation independent from the investigating laboratory. Disappointing results of recent national and international immunohistochemistry trials for steroid receptor and HER-2 analysis in breast cancer underline the need to act now beyond recommendations and well-formulated guidelines for standardization. In order to ensure staining quality in every individual immunohistochemical analysis, we have developed an on-slide control with standardized samples which are placed on every slide of a therapy-decisive stain together with the tissue of interest. Novel mini tissue microarrays were constructed comprising cell lines as standardized controls, indicating the sensitivity and reliability of the staining procedure. Standardized control material on the same slide as the patient's specimen require neither additional reagents nor time and are automatically archived on the diagnostic slide to prove the quality of staining even after years. [ABSTRACT FROM AUTHOR]

Female hormones, especially estrogens, play an important role in the pathogenesis of breast neoplasms and are a principal determinant of their biological behavior. Endocrine manipulation through medical or surgical means can often lead to objective shrinkage of breast tumors. Tamoxifen, a triphenylethylene estrogen receptor modulator, is currently the most widely used hormonal treatment for breast cancer. It has been conclusively demonstrated to reduce the risk of relapse following definitive local therapy (and systemic chemotherapy, when indicated) of invasive or noninvasive breast cancer. Recently, it has also been shown to reduce the incidence of breast cancer in healthy women who are at high risk of developing the disease. In addition, it can prevent osteoporosis and reduce the risk of fractures in postmenopausal women. However, its use is also complicated by an increased incidence of endometrial hyperplasia/carcinoma, venous thromboembolism, cataracts, and in some cases, emergence of tamoxifen-dependent clones of breast cancer. These side effects (except cataracts) are believed to be related to estrogen-agonist effects of tamoxifen. Newer drugs, which are "pure antiestrogens" or inhibitors of estrogen biosynthesis, are devoid of such estrogen-agonist activity and may not have the liability of many of these side effects. However, these agents would also be expected to lack the potentially beneficial effects of tamoxifen on lipids and skeletal system. The ability of tamoxifen to act as an estrogen-agonist or estrogen-antagonist in a tissue-specific fashion has led to the concept of selective estrogen-receptor modulation. Selective estrogen receptor modulators (SERMs), which are devoid of estrogen-agonist effects on the uterus or breast cancer cells but retain potentially beneficial effects on bones and lipids, have been described as "ideal" SERMs. A number of such compounds are currently being tested. Raloxifene is already approved for prevention of osteoporosis and has potential efficacy for prevention and treatment of breast cancer. An analogue of raloxifene, LY353381, is currently in Phase II clinical trials for treatment of breast cancer, with promising early results. EM800 and CP336156 are other promising ideal SERMs in clinical trials. These compounds may provide better treatment and chemoprevention alternatives for breast cancer as compared to tamoxifen, aromatase inhibitors, and pure antiestrogens. In addition, they may also prove to be useful for the treatment and prevention of prostate cancer as well as for treating benign gynecological diseases such as fibroids and endometriosis. Future laboratory efforts should focus on further broadening the efficacy profile of SERMs (e.g., prevention of Alzheimer's disease and elevation of high-density lipoproteins to improve the likelihood of cardiovascular benefit) and narrowing their side-effect profile (e.g., risk of thromboembolism and hot flashes). [ABSTRACT FROM AUTHOR]

DNA methylation is an epigenetic modification that is associated with transcriptional silencing of gene expression in mammalian cells. Hypermethylation of the promoter CpG islands contributes to the loss of gene function of several tumor related genes, including estrogen receptor α (ER) and progesterone receptor (PR). Gene expression patterns are also heavily influenced by changes in chromatin structure during transcription. Indeed both the predominant mammalian DNA methyltransferase (DNMT1), and the histone deacetylases (HDACs) play crucial roles in maintaining transcriptionally repressive chromatin by forming suppressive complexes at replication foci. These new findings suggest that epigenetic changes might play a crucial role in gene inactivation in breast cancer. Further, inhibition of DNA methylation and histone deacetylation might be a therapeutic strategy in breast cancer, especially for those cancers with ER and PR negative phenotypes. [ABSTRACT FROM AUTHOR]

Receptor assay results were compared with the ultrastructure of 127 breast cancers (112 primary tumors, six recurrent lesions, nine metastases). Tumors were considered to be receptor positive if the receptor levels were ⩾ 15 fmol/mg of soluble tissue protein. Most breast cancer had heterogenous cells with different grades of ultrastructural differentiation. A prevalence of well-differentiated cancer cells and an abundance of intracytoplasmic vacuoles had a significant correlation with a positive estrogen receptor status. The correlation was better than between malignancy grades and receptor content. The type of breast cancer and the menopausal status bore no relation to receptor content. Progesterone receptors were found in well-differentiated tumors of low malignancy. [ABSTRACT FROM AUTHOR]

Breast cancer is a major cause of morbidity and mortality in women in many parts of the world. Breast carcinomas are heterogenous in their biological and clinical behaviour and a greater understanding of how they develop and progress could lead to more directed forms of screening and therapy. It is important to determine the molecular mechanisms underlying the natural history of breast cancer. Developments in the techniques for molecular analysis have meant that they can now be applied to a large range of clinical material such as cytological preparations and fixed, embedded material, so increasing the potential for relating any molecular alterations to clinical behaviour and response to therapy. In this review we consider recent developments in three areas of importance to breast cancer; genetic analysis — oncogenes, tumour suppressor genes, loss of heterozygosity, microsatellite instability, familial breast cancer; steroid receptors, oestrogen regulated proteins, epidermal growth factor receptor, growth factors particularly transforming growth factor beta; and cell adhesion, invasion and metastasis — E-cadherin, integrins, proteases. These are discussed in relation to potential for screening, prognosis and treatment. [ABSTRACT FROM AUTHOR]