Endocrine Treatment Of Breast Cancer Research Articles

Time required to start multicentre clinical trials within the Italian Medicine Agency programme of support for independent research

Background and aimTime allowed for independent ethics committees (IECs) and administrative offices to assess and activate clinical trials is regulated by law. This study aims to describe time spent activating...

Protein bomarkers Ki67, HOXC10 and HOXC11 for the prediction of response to endocrine treatment in breast cancer

Protein bomarkers Ki67, HOXC10 and HOXC11 for the prediction of response to endocrine treatment in breast cancer

Endocrine therapy for breast cancer: past and present

The endocrine therapy for breast cancer could be traced back to the excision of the metastatic breast cancer by oophorectomy in a premenopausal women performed by Beatson in 1896. After the development of more than 100 years, endocrine therapy plays an important role in adjuvant therapy, the rescuing treatment of its recurrence due to metastasis, and the new adjuvant endocrine therapy for breast cancer. Through analyzing the changes in the 4 aspects of endocrine treatment of breast cancer, i.e., the original simple excision of the endocrine organs, tamoxifen, drug-induced ovarian castration and the 3th generation aromatase inhibitor, the characteristics of different ages of endocrine therapy can be summarized, which would provide the reference for the new developmental trend of this therapy.

Aromatase Inhibitor-Induced Erythrocytosis in a Patient Undergoing Hormonal Treatment for Breast Cancer.

Aromatase inhibitors (AIs) are most commonly used for breast cancer patients with hormone receptor positive disease. Although the side effect profile of aromatase inhibitors is well known, including common side effects like arthralgia, bone pain, arthritis, hot flashes, and more serious problems like osteoporosis, we present a case of an uncommon side effect of these medications. We report the case of a postmenopausal woman on adjuvant hormonal therapy with anastrozole after completing definitive therapy for stage IIIB estrogen receptor-positive breast cancer, who was referred to hematology service for evaluation of persistent erythrocytosis. Primary and known secondary causes of polycythemia were ruled out. On further evaluation, we found that her erythrocytosis began after initiation of anastrozole and resolved after it was discontinued. We discuss the pathophysiology of aromatase inhibitor-induced erythrocytosis and reference of similar cases reported in the literature.

The role of oestrogen and progesterone receptors in breast cancer - immunohistochemical evaluation of oestrogen and progesterone receptor expression in invasive breast cancer in women.

Aim of the studyExpression of oestrogen and progesterone receptors is a very powerful and useful predictor. Because the response rate to hormonal treatment in breast cancer is associated with the presence of oestrogen and progesterone receptors, assessment of the receptor expression profile allows for prediction of breast cancer response to hormonal treatment. The aim of this study was to assess whether the expression of receptors for oestrogen (ER) and progesterone (PR) in the tumour tissue of patients with invasive breast cancer correlated with tumour histological type, histological grade of malignancy, tumour size, and lymph node status.Material and methodsMaterials consisted of histological preparations derived from patients treated for invasive breast cancer. Evaluations were conducted with histopathological and immunohistochemical methods using suitable antibodies.ResultsAmong 231 cases of breast cancer 18 invasive lobular carcinomas (ILC) and 213 invasive ductal carcinomas (IDC) were diagnosed. Taking the histological type of tumour into account, oestrogen receptor-positive reaction was observed in 74.2% of IDC and 77.8% of ILC, and the positive response to PR was observed in 67.1% of IDC and 61.1% of ILC. Considering the histological grade, ER- in the largest percentage (72%) was observed in second-grade (G2) invasive carcinomas. Similarly, PR expression (75%) was found in the largest percentage in second-grade (G2) carcinomas. Based on our own studies and data from literature, it appears that the ER (+) status is an indicator of good prognosis, because it points to a less aggressive cancer, in which overall survival and disease-free time is longer in comparison with ER (–) tumours.ConclusionsDetermination of ER status may, therefore, have significant clinical value and is widely used in routine pathological diagnostics.

Arthralgia induced by endocrine treatment for breast cancer: A prospective study of serum levels of insulin like growth factor-I, its binding protein and oestrogens

BackgroundAromatase inhibitors (AIs) frequently induce or enhance musculoskeletal problems (AI-induced musculoskeletal syndrome (AIMSS)) which sometimes are debilitating. Apart from low oestrogen levels, underlying mechanisms are unknown and likely multiple. We previously hypothesised a role for the growth hormone/insulin like growth factor-I (IGF-I) axis. Here, we report the effect of tamoxifen and AI on IGF-I, IGF binding protein-3 (IGFBP-3) and oestrogen levels from a prospective study. Materials and methodsPostmenopausal women with an early breast cancer scheduled to start adjuvant endocrine therapy with an AI or tamoxifen were recruited. A rheumatologic questionnaire was completed and serum was collected for assessment of IGF-I, IGFBP-3 and oestrogen levels. Re-evaluation was done after 3, 6 and 12months of therapy. Results84 patients started on tamoxifen (n=42) or an AI (n=42). 66% of the latter group experienced worsening of pre-existing or de novo complaints in joint and/or muscle, compared to 29% of tamoxifen-treated patients. AI therapy resulted in elevated IGF-I levels with a statistically significant increase at 6months (p=0.0088), whereas tamoxifen users were characterised by a decrease in IGF-I levels at all follow-up times (p<0.0004). No effect on IGFBP-3 was seen in the latter group. AI-users, however, showed decreased IGFBP-3 levels at 12months (p=0.0467). AIMSS was characterised by a decrease in IGFBP-3 levels (p=0.0007) and a trend towards increased IGF-I/IGFBP-3 ratio (p=0.0710). ConclusionThese findings provide preliminary evidence that AI-induced musculoskeletal symptoms are associated with changes in the growth hormone (GH)/IGF-I axis.

Trigger Fingers as a Side-Effect of Aromatase Inhibitors: A Case Report

To demonstrate how adjuvant endocrine treatment for breast cancer using aromatase inhibitors raises ethical and clinical issues.

Emerging strategies to overcome resistance to endocrine therapy for breast cancer.

Endocrine therapy of breast cancer is perhaps the oldest form of effective and well-tolerated targeted cancer systemic treatment, in both the adjuvant and metastatic disease settings. The most commonly used endocrine therapy agents are selective estrogen receptor modulators, aromatase inhibitors, and selective estrogen receptor downregulators. De novo or acquired resistance to these agents is a significant clinical problem. Preclinical and clinical investigations to understand this resistance have yielded significant advances in understanding cell signaling and the possible mechanisms of resistance. These mechanisms of resistance are as diverse as the biology of breast cancer and can arise from alterations in any of the cell signaling pathway components. A growing understanding of these mechanisms has provided rationale for development of strategies to overcome the resistance. Many of these mechanisms of resistance involve adaptive upregulation of alternate signaling pathways, such as growth factor signaling, and cross talk between estrogen receptor and growth factor signaling. Clinical trials are focusing on cotargeting these alternate pathways along with estrogen receptor signaling. It is becoming evident that, as with all cancer therapy, strategies to overcome resistance need to be individualized, and it is important to identify biomarkers to guide the use of these strategies. This manuscript systemically reviews the recent preclinical and clinical trials on the novel and pathway-driven agents that have shown significant promise in enhancing the efficacy and overcoming the resistance in the hormonal treatment of breast cancer. Future directions including biomarker selection and the role of next generation sequencing will be discussed.

Anti-aromatase effect of resveratrol and melatonin on hormonal positive breast cancer cells co-cultured with breast adipose fibroblasts

Targeting the estrogen pathway has been proven effective in the treatment for estrogen receptor positive breast cancer. There are currently two common groups of anti-estrogenic compounds used in the clinic; Selective Estrogen Receptor Modulators (SERMs, e.g. tamoxifen) and Selective Estrogen Enzyme Modulators (SEEMs e.g. letrozole). Among various naturally occurring, biologically active compounds, resveratrol and melatonin have been suggested to act as aromatase inhibitors, which make them potential candidates in hormonal treatment of breast cancer. Here we used a co-culture model in which we previously demonstrated that primary human breast adipose fibroblasts (BAFs) can convert testosterone to estradiol, which subsequently results in estrogen receptor-mediated breast cancer T47D cell proliferation. In the presence of testosterone in this model, we examined the effect of letrozole, resveratrol and melatonin on cell proliferation, estradiol (E2) production and gene expression of CYP19A1, pS2 and Ki-67. Both melatonin and resveratrol were found to be aromatase inhibitors in this co-culture system, albeit at different concentrations. Our co-culture model did not provide any indications that melatonin is also a selective estrogen receptor modulator. In the T47D-BAF co-culture, a melatonin concentration of 20nM and resveratrol concentration of 20μM have an aromatase inhibitory effect as potent as 20nM letrozole, which is a clinically used anti-aromatase drug in breast cancer treatment. The SEEM mechanism of action of especially melatonin clearly offers potential advantages for breast cancer treatment.

Selection of Personalized Patient Therapy through the Use of Knowledge-Based Computational Models That Identify Tumor-Driving Signal Transduction Pathways

Increasing knowledge about signal transduction pathways as drivers of cancer growth has elicited the development of "targeted drugs," which inhibit aberrant signaling pathways. They require a companion diagnostic test that identifies the tumor-driving pathway; however, currently available tests like estrogen receptor (ER) protein expression for hormonal treatment of breast cancer do not reliably predict therapy response, at least in part because they do not adequately assess functional pathway activity. We describe a novel approach to predict signaling pathway activity based on knowledge-based Bayesian computational models, which interpret quantitative transcriptome data as the functional output of an active signaling pathway, by using expression levels of transcriptional target genes. Following calibration on only a small number of cell lines or cohorts of patient data, they provide a reliable assessment of signaling pathway activity in tumors of different tissue origin. As proof of principle, models for the canonical Wnt and ER pathways are presented, including initial clinical validation on independent datasets from various cancer types.

Hormone Receptors and Her2 Expression in Breast Cancer in Sub-Saharan Africa. A Comparative Study of Biopsies from Ghana and Norway

Hormonal treatment of breast cancer is effective only in patients whose tumors express estrogen and/or progesterone receptors (ER, PR). Receptor assessment is often not available in low-resource areas, and the choice may be to apply endocrine therapy to all or none of breast cancer patients, depending on the proportion of patients that can be expected to respond. Fifty-one invasive breast cancers from Ghana and 100 from Norway diagnosed in the same laboratory during the same time period were reexamined in a blinded slide review. Of Ghanaian tumors, 76% were ER+ (≥1% ER+ tumor cells). Of Norwegian tumors, 85% were ER+. Triple-negative tumors were seen in 22% of Ghanaian patients and in 7% of Norwegian patients. A review of previous similar studies in sub-Saharan patients shows very discrepant results. Standardization and quality control of receptor assessment and well-designed clinical trials in sub-Saharan African breast cancer patients are needed to give a sound basis for endocrine treatment in this area.

Neoadjuvant endocrine treatment in breast cancer: analysis of daily practice in large cancer center to facilitate decision making

BackgroundTo examine outcomes of neoadjuvant endocrine therapy in daily practice to inform decision making. MethodsWe retrospectively selected 204 patients who received neoadjuvant endocrine therapy with T2 (≥30 mm) or T3 tumors, examining subsequent breast-sparing surgery and long-term outcomes. ResultsNeoadjuvant endocrine therapy was administered for 7.3 months (median) and breast-sparing surgery was achievable in 53% of patients. Smaller initial tumor size and modified version of the Scarff–Bloom and Richardson grades 1 to 2 were associated with breast-sparing surgery. Disease progression during treatment was 6.9%; actuarial risk of local relapse was 3% at 5 years and 15% at 10 years. Five- and 10-year metastasis relapse-free survival was 78% and 63%, respectively. Grade 3, negative progesterone receptors, and absence or slow response to neoadjuvant therapy were associated prognostic factors. ConclusionThese daily practice data provide important information about feasibility, efficacy, and long-term results of neoadjuvant endocrine therapy and can be used to inform patients for decision making between mastectomy and endocrine induction therapy.

Dynamics of IGF-1R Expression During Endocrine Breast Cancer Treatment

The aim was to assess changes in insulin-like growth factor 1 receptor (IGF-1R) expression with immunoSPECT/CT and to study the dynamics of IGF-1R expression of human breast tumors during endocrine treatment. Mice with MCF-7 xenografts were treated with estradiol or tamoxifen, and IGF-1R expression was measured by immunohistochemistry and immunoSPECT/CT using (111)In-R1507 (anti-IGF-1R antibody). Moreover, IGF-1R expression was analyzed immunohistochemically on 22 human breast tumors, treated preoperatively with endocrine therapy. Estradiol resulted in an increased expression of IGF-1R, as measured by immunohistochemistry and immunoSPECT/CT. In contrast, tamoxifen resulted in a downregulation of IGF-1R, whereas this could not be measured with immunoSPECT/CT. A downregulation was also detectable in 9 out of 22 (41 %) human breast tumors after endocrine therapy. Anti-estrogen treatment can cause a reduction in membranous IGF-1R expression. Based on these results, a combination of anti-IGF-1R antibodies with anti-estrogen therapy might not be a rational treatment strategy.

ESR1gene promoter region methylation in free circulating DNA and its correlation with estrogen receptor protein expression in tumor tissue in breast cancer patients

BackgroundTumor expression of estrogen receptor (ER) is an important marker of prognosis, and is predictive of response to endocrine therapy in breast cancer. Several studies have observed that epigenetic events, such methylation of cytosines and deacetylation of histones, are involved in the complex mechanisms that regulate promoter transcription. However, the exact interplay of these factors in transcription activity is not well understood. In this study, we explored the relationship between ER expression status in tumor tissue samples and the methylation of the 5′ CpG promoter region of the estrogen receptor gene (ESR1) isolated from free circulating DNA (fcDNA) in plasma samples from breast cancer patients.MethodsPatients (n = 110) with non-metastatic breast cancer had analyses performed of ER expression (luminal phenotype in tumor tissue, by immunohistochemistry method), and the ESR1-DNA methylation status (fcDNA in plasma, by quantitative methylation specific PCR technique).ResultsOur results showed a significant association between presence of methylated ESR1 in patients with breast cancer and ER negative status in the tumor tissue (p = 0.0179). There was a trend towards a higher probability of ESR1-methylation in those phenotypes with poor prognosis i.e. 80% of triple negative patients, 60% of HER2 patients, compared to 28% and 5.9% of patients with better prognosis such as luminal A and luminal B, respectively.ConclusionSilencing, by methylation, of the promoter region of the ESR1 affects the expression of the estrogen receptor protein in tumors of breast cancer patients; high methylation of ESR1-DNA is associated with estrogen receptor negative status which, in turn, may be implicated in the patient’s resistance to hormonal treatment in breast cancer. As such, epigenetic markers in plasma may be of interest as new targets for anticancer therapy, especially with respect to endocrine treatment.

The G Protein-Coupled Estrogen Receptor (GPER) Is Expressed in Two Different Subcellular Localizations Reflecting Distinct Tumor Properties in Breast Cancer

IntroductionThe G protein-coupled estrogen receptor (GPER) is a novel estrogen receptor that mediates proliferative effects induced by estrogen but also by tamoxifen. The aim of our study was to analyze the frequency of GPER in a large collective of primary invasive breast carcinomas, with special emphasis on the subcellular expression and to evaluate the association with clinicopathological parameters and patient overall survival.MethodsThe tissue microarrays from formalin-fixed, paraffin embedded samples of primary invasive breast carcinomas (n = 981) were analyzed for GPER expression using immunohistochemistry. Expression data were compared to the clinicopathological parameters and overall survival. GPER localization was also analyzed in two immortalized breast cancer cell lines T47D and MCF7 by confocal immunofluorescence microscopy.ResultsA predominantly cytoplasmic GPER expression was found in 189 carcinomas (19.3%), whereas a predominantly nuclear expression was observed in 529 cases (53.9%). A simultaneous comparable positive expression of both patterns was found in 32 of 981 cases (3.2%), and negative staining was detected in 295 cases (30%). Confocal microscopy confirmed the occurrence of cytoplasmic and nuclear GPER expression in T47D and MCF7. Cytoplasmic GPER expression was significantly associated with non-ductal histologic subtypes, low tumor stage, better histologic differentiation, as well as Luminal A and B subtypes. In contrast, nuclear GPER expression was significantly associated with poorly differentiated carcinomas and the triple-negative subtype. In univariate analysis, cytoplasmic GPER expression was associated with better overall survival (p = 0.012).ConclusionOur data suggest that predominantly cytoplasmic and/or nuclear GPER expression are two distinct immunohistochemical patterns in breast carcinomas and may reflect different biological features, reason why these patterns should be clearly distinguished in histological evaluations. Prospective studies will be needed to assess whether the expression status of GPER in breast carcinomas should be routinely observed by clinicians, for instance, before implementing endocrine breast cancer treatment.

Neoadjuvant endocrine treatment for breast cancer: from bedside to bench and back again?

In recent years, considerable attention has been paid to the role of neoadjuvant chemotherapy as a pluripotential test bed for the treatment of breast cancer. Although traditionally reserved to render inoperable disease operable, neoadjuvant chemotherapy is increasingly being used to improve the chance for breast-conserving surgery, to gain information on pathologic response rates for a more rapid assessment of new chemotherapy-biologic regimens, and also to study in vivo tumour sensitivity or resistance to the agent being used. Similarly, use of neoadjuvant endocrine treatment was also traditionally restricted to elderly or frail patients who were felt to be unsuitable for chemotherapy. It is therefore not surprising that, given the increasing realization of the pivotal role of endocrine therapy in patient care, there is enhanced interest in neoadjuvant endocrine therapy not only as a less-toxic alternative to chemotherapy, but also to assess tumour sensitivity or resistance to endocrine agents. The availability of newer endocrine manipulations and increasing evidence that the benefits of chemotherapy are frequently marginal in many hormone-positive patients is making endocrine therapy increasingly important in the clinical setting. The hope is that, one day, instead of preoperative endocrine therapy being restricted to the infirm and the elderly, it will be used in the time between biopsy diagnosis and surgery to predict which patients will or will not benefit from chemotherapy in the adjuvant setting.

Expression of Estrogen-Related Gene Markers in Breast Cancer Tissue Predicts Aromatase Inhibitor Responsiveness

Aromatase inhibitors (AIs) are the most effective class of drugs in the endocrine treatment of breast cancer, with an approximate 50% treatment response rate. Our objective was to determine whether intratumoral expression levels of estrogen-related genes are predictive of AI responsiveness in postmenopausal women with breast cancer. Primary breast carcinomas were obtained from 112 women who received AI therapy after failing adjuvant tamoxifen therapy and developing recurrent breast cancer. Tumor ERα and PR protein expression were analyzed by immunohistochemistry (IHC). Messenger RNA (mRNA) levels of 5 estrogen-related genes–AKR1C3, aromatase, ERα, and 2 estradiol/ERα target genes, BRCA1 and PR–were measured by real-time PCR. Tumor protein and mRNA levels were compared with breast cancer progression rates to determine predictive accuracy. Responsiveness to AI therapy–defined as the combined complete response, partial response, and stable disease rates for at least 6 months–was 51%; rates were 56% in ERα-IHC-positive and 14% in ERα-IHC-negative tumors. Levels of ERα, PR, or BRCA1 mRNA were independently predictive for responsiveness to AI. In cross-validated analyses, a combined measurement of tumor ERα and PR mRNA levels yielded a more superior specificity (36%) and identical sensitivity (96%) to the current clinical practice (ERα/PR-IHC). In patients with ERα/PR-IHC-negative tumors, analysis of mRNA expression revealed either non-significant trends or statistically significant positive predictive values for AI responsiveness. In conclusion, expression levels of estrogen-related mRNAs are predictive for AI responsiveness in postmenopausal women with breast cancer, and mRNA expression analysis may improve patient selection.

MC13-0036 Dynamics of IGF-1R expression during endocrine breast cancer treatment

MC13-0036 Dynamics of IGF-1R expression during endocrine breast cancer treatment

Gene expression markers in circulating tumor cells may predict bone metastasis and response to hormonal treatment in breast cancer

Circulating tumor cells (CTCs) have recently attracted attention due to their potential as prognostic and predictive markers for the clinical management of metastatic breast cancer patients. The isolation of CTCs from patients may enable the molecular characterization of these cells, which may help establish a minimally invasive assay for the prediction of metastasis and further optimization of treatment. Molecular markers of proven clinical value may therefore be useful in predicting disease aggressiveness and response to treatment. In our earlier study, we identified a gene signature in breast cancer that appears to be significantly associated with bone metastasis. Among the genes that constitute this signature, trefoil factor 1 (TFF1) was identified as the most differentially expressed gene associated with bone metastasis. In this study, we investigated 25 candidate gene markers in the CTCs of metastatic breast cancer patients with different metastatic sites. The panel of the 25 markers was investigated in 80 baseline samples (first blood draw of CTCs) and 30 follow-up samples. In addition, 40 healthy blood donors (HBDs) were analyzed as controls. The assay was performed using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) with RNA extracted from CTCs captured by the CellSearch system. Our study indicated that 12 of the genes were uniquely expressed in CTCs and 10 were highly expressed in the CTCs obtained from patients compared to those obtained from HBDs. Among these genes, the expression of keratin 19 was highly correlated with the CTC count. The TFF1 expression in CTCs was a strong predictor of bone metastasis and the patients with a high expression of estrogen receptor β in CTCs exhibited a better response to hormonal treatment. Molecular characterization of these genes in CTCs may provide a better understanding of the mechanism underlying tumor metastasis and identify gene markers in CTCs for predicting disease progression and response to treatment.

Abstract 99: Identification of genes involved in NFκB driven resistance to endocrine treatment in breast cancer.

Abstract Introduction: Breast cancer is a heterogeneous disease exemplified by patients with Estrogen Receptor (ER) positive and negative breast cancer. Treatment of patients with breast cancer is increasingly governed by this notion of heterogeneity. For example, patients with ER+ breast cancer are treated with endocrine therapy. Although endocrine treatment is the mainstay of therapy for patients with ER+ breast cancer, resistance to endocrine therapy is a major clinical problem. Recently we identified a 6-gene signature predictive of Tamoxifen sensitivity. In addition, our earlier work has shown the importance of the NFkB transcription factor family in determining ER function. In this study, we aim to elucidate the role of NFkB in endocrine therapy response. Materials and methods: Public gene expression data sets of breast cancer patients and cell lines have been analyzed. ER- (PAM50-model) and NFkB-activation signatures (Annunziata et al, Cancer Cell, 2007) were calculated for all samples. In addition, samples were classified using our Tamoxifen response gene signature. We selected 11 cell lines with presumed strong or weak activation of NFkB based on the analysis of NFkB target gene expression. These cell lines were analyzed for NFkB DNA-binding using the TransAM ELISA kits (Active Motif). ER and NFkB target gene expression was determined using qRT-PCR. In addition, the expression of the 6 endocrine therapy responsive genes (ABAT, ADAMDEC1, CLEC7A, ETS1, ITK and STC2) was evaluated. Results: When analyzing the NFkB activation signature in ∼700 samples from patients with breast cancer, we clearly observed an inverse correlation with the ER activation signature (R=-0.65, P&amp;lt;0.01). Also, we observed NFkB hyperactivation in ER- breast cancers (P&amp;lt;0.01). When restricting our analysis to ER+ samples, we demonstrated NFkB hyperactivation in samples from patients predicted by our 6-gene signature to be resistant to endocrine therapy. NFkB DNA-binding experiments confirmed the gene expression based NFkB activation status of eleven selected cell lines. In addition, NFkB DNA-binding was associated with elevated expression of ADAMDEC1 and ETS1 and reduced expression of ABAT (All Ps&amp;lt;0.05). Finally, the 6-gene signature predictive of Tamoxifen response showed an increased expression in cell lines with increased NFkB DNA-binding (P&amp;lt;0.01). Conclusion: In the present study we demonstrate that NFkB activation is associated with attenuated response to endocrine treatment in patients with breast cancer. Our data suggest that this association is due to a repressive effect of NFkB on ER but mechanistic data in support of this view are currently lacking. We propose that the panel of cell lines evaluated in part of the present study will prove to be helpful instrument in elucidating the role of the interaction between ER and NFkB in endocrine treatment resistance. Citation Format: Leen Sas, Peter Van Dam, Luc Dirix, Peter Vermeulen, Filip Lardon, Steven Van Laere. Identification of genes involved in NFκB driven resistance to endocrine treatment in breast cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 99. doi:10.1158/1538-7445.AM2013-99