Estrogen Receptor In Breast Cancer Research Articles

Abstract P5-07-15: Breast cancer estrogen receptor scoring in tissue microarrays: Specialist breast pathologist versus automation

Abstract Rationale: Tissue microarrays (TMAs) have become a valuable resource for biomarker expression in translational research. Immunohistochemical (IHC) assessment of TMAs is the principal method for analyzing protein expression in large numbers of patient samples efficient with conservation of tissue. However, manual IHC assessment of TMAs remains a challenging and laborious task. With advances in image analysis, computer generated analyses of TMAs have the potential to lessen the burden of expert pathologist review. Computerized ER scoring relies on tumor localization. Aim: The objective of this study was to compare the effectiveness of a locally developed automated invasive tumor location system with the skills of specialist breast pathologists. Methods: In this study, tumor localization for estrogen receptor (ER) scoring was evaluated comparing computer- generated segmentation masks with those of two specialist breast pathologists. Automated tumor localization was achieved using a novel image analysis algorithm, which labeled compact groups of pixels called superpixels. Machine learning techniques were adopted to model color, shape and textural properties of superpixels in a rotation invariant manner, suitable for histopathology images. The resulting automatically and manually-obtained segmentation masks were used to obtain IHC scores for thirty-two ER stained invasive breast cancer TMA samples using FDA-approved IHC scoring software. Results: Pixel-level comparisons showed lower agreement between automated and manual segmentation masks (κ = 0.84) than between pathologists' masks (κ = 0.91). However, this had little impact on computed IHC scores (Allred method; κ = 0.91, Quickscore method; κ = 0.92). Conclusion: The automated system provides sufficiently consistent measurements for standardized IHC analysis of nuclear staining in TMAs from large clinical trials. Citation Format: Jordan LB, Akbar S, Purdie CA, Thompson AM, McKenna SJ. Breast cancer estrogen receptor scoring in tissue microarrays: Specialist breast pathologist versus automation. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-07-15.

Abstract P1-14-07: Association between quantitative values of estrogen receptor expression level and pathological complete response in human epidermal growth factor 2-negative breast cancer: Should the clinical definition of triple-negative breast cancer be redefined?

Abstract Background: The American Society of Clinical Oncology/College of American Pathologists recommended that the cut-off for negative status of estrogen receptor (ER) should be <1% positively staining cells, although a 10% cut-off has often been used clinically. Prior studies reported that patients with ER ranging from 1% to 9% showed survival outcomes and molecular features similar to those of patients with ER positivity of <1%; however, those studies did not take into account patients' human epidermal growth factor 2 (HER2) status. This means we have yet to clarify the exact clinical definition of triple-negative breast cancer (TNBC) on the basis of response to preoperative chemotherapy. Previous studies reported that hormone receptor–positive tumors were less sensitive to systemic chemotherapies. On the basis of these facts, we hypothesized that in patients with HER2-negative breast cancer ER expression level as a continuous variable has an inverse linear association with pathological complete response (pCR) rate. Our primary objective was to determine whether a quantitative value of ER between 0% and 10% is predictive of pCR rate in HER2-negative patients treated with neoadjuvant chemotherapy. Secondary objective was to find the ideal cut-off value of ER expression. Methods: We included newly diagnosed stage I-III HER2-negative breast cancer patients with available ER (0%≤ER<10%) who were treated with neoadjuvant systemic chemotherapy. ER status was determined by immunohistochemical (IHC) staining; HER2 status was determined by IHC and/or FISH. We used univariate and multivariate logistic regression models to determine the association between baseline variables and pCR. A backward stepwise method was used to select the covariates for the multivariate analysis. Recursive partitioning and regression tree method were used to identify the potential significant cut-off of ER. Results: The analysis included 1155 patients with newly diagnosed HER2-negative invasive breast cancer. The univariate logistic regression analysis showed that ER as a continuous variable was not a statistically significant factor for predicting pCR (ER: OR=0.98, 95%CI: 0.9-1.07, P=0.68). In the multivariate analysis, ER status again was not a significant factor for predicting pCR (OR=0.97, 95%CI 0.9-1.06, P=0.55). ER as a categorical variable, there was no significant difference of the pCR rate between 0<ER<1 and 1≤ER<10 groups (OR=1.27, 95%CI: 0.62-2.62, P=0.52). Among ER> 0 (n=229), the recommended cut-off value of ER was 5.5. However, the odds ratio of pCR rate divided by this value of 5.5 was not significant (ER≤5 vs ER>5; OR 1.94 95%CI 0.54-6.95 P=0.31). Conclusion: Evaluating ER (<10%) as a continuous variable showed no association with pCR rate, and no cut-off of ER was identified with which to stratify patients into groups more or less likely to achieve pCR. A potential meaningful cut-off ER value might exist between 10% and 100% in HER2-negative patients. We will explore whether a meaningful cut-off ER value exists that will change the pCR rate and possibly lead to redefining the clinical definition of TNBC. Citation Format: Fujii T, Kogawa T, Dong W, Moulder S, Litton JK, Tripathy D, Lim B, Shen Y, Ueno NT. Association between quantitative values of estrogen receptor expression level and pathological complete response in human epidermal growth factor 2-negative breast cancer: Should the clinical definition of triple-negative breast cancer be redefined?. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-14-07.

Estrogen-Receptor, Progesterone-Receptor and HER2 Status Determination in Invasive Breast Cancer. Concordance between Immuno-Histochemistry and MapQuant™ Microarray Based Assay.

BackgroundHormone receptor status and HER2 status are of critical interest in determining the prognosis of breast cancer patients. Their status is routinely assessed by immunohistochemistry (IHC). However, it is subject to intra-laboratory and inter-laboratory variability. The aim of our study was to compare the estrogen receptor, progesterone receptor and HER2 status as determined by the MapQuant™ test to the routine immuno-histochemical tests in early stage invasive breast cancer in a large comprehensive cancer center.Patients and MethodsWe retrospectively studied 163 invasive early-stage breast carcinoma with standard IHC status. The genomic status was determined using the MapQuant™ test providing the genomic grade index.ResultsWe found only 4 tumours out of 161 (2.5%) with discrepant IHC and genomic results concerning ER status. The concordance rate between the two methods was 97.5% and the Cohen’s Kappa coefficient was 0.89.Comparison between the MapQuant™ PR status and the PR IHC status gave more discrepancies. The concordance rate between the two methods was 91.4% and the Cohen’s Kappa coefficient was 0.74.The HER2 MapQuant™ test was classified as « undetermined » in 2 out of 163 cases (1.2%). One HER2 IHC-negative tumour was found positive with a high HER2 MapQuant™ genomic score. The concordance rate between the two methods was 99.3% and the Cohen’s Kappa coefficient was 0.86.ConclusionOur results show that the MapQuant™ assay, based on mRNA expression assay, provides an objective and quantitative assessment of Estrogen receptor, Progesterone receptor and HER2 status in invasive breast cancer.

S100A8/A9 is associated with estrogen receptor loss in breast cancer.

S100A8 and S100A9 are calcium-binding proteins that are secreted primarily by granulocytes and monocytes, and are upregulated during the inflammatory response. S100A8 and S100A9 have been identified to be expressed by epithelial cells involved in malignancy. In the present study, the transcriptional levels of S100A8 and S100A9 were investigated in various subtypes of breast cancer (BC), and the correlation with estrogen receptor 1 (ESR1) and GATA binding protein 3 (GATA3) gene expression was evaluated using microarray datasets. The expression of S100A8 and S100A9 in BC cells was assessed by reverse transcription-polymerase chain reaction (RT-PCR). The regulation of ESR1 and GATA3 by administration of recombinant S100A8/A9 was examined in the BC MCF-7 cell line using quantitative (q)PCR. The association between S100A8 and S100A9 and overall survival (OS) was investigated in GeneChip® data of BC. The expression levels of S100A8 and S100A9 were higher in human epidermal growth factor receptor 2 (Her2)-amplified and basal-like BC. The messenger (m)RNA levels of S100A8 and S100A9 were inversely correlated with ESR1 and GATA3 expression. S100A8/A9 induced a 10-fold decrease in the mRNA levels of ESR1 in MCF-7 cells. Poor OS was associated with high expression levels of S100A9, but not with high expression levels of S100A8 in BC. In conclusion, strong expression and secretion of S100A8/A9 may be associated with the loss of estrogen receptor in BC, and may be involved in the poor prognosis of Her2+/basal-like subtypes of BC.

Genistein-induced differentiation of breast cancer stem/progenitor cells through a paracrine mechanism.

It is believed that breast cancer stem cells (BCSCs), like normal stem cell counterparts, have the capacity of self-renewal and differentiation. Simultaneously, estrogen receptor (ER)-negative (-) BCSCs are affected by surrounding differentiated ER-positive (+) tumor cells by virtue of paracrine signaling within the tumor micro-environment. Genistein (GEN), as a sort of phytoestrogen, can act on ER+ breast cancer cells but the role of GEN in the differentiation of neighboring ER- BCSCs has not been defined. Transwell co-culture system was utilized so as to elaborate the interaction between well-differentiated ER+ breast cancer cells (MCF-7) and ER- breast cancer stem/progenitor cells (mammospheres derived from MDA-MB-231 cells). GEN-induced differentiation of BCSCs was analyzed by mammospheres formation assay, flow cytometry and RT-PCR after a 3 day solo-culture or co-culture. We find that GEN sized 2 µM, and 40 nM, effectively promotes morphological alteration of mammospheres, reduces the ratio of subset of CD44+/CD24-/ESA+ cells and upregulates the expression of differentiated cell markers of mammospheres in co-culture system, but not in solo-culture condition. Besides, we demonstrate that the differentiation-inducing effect of GEN on mammospheres is associated with PI3K/Akt and MEK/ERK signaling pathways which are activated by amphiregulin released from ER+ cancer cells. These results indicate that GEN was able to induce the differentiation of breast cancer stem/progenitor cells through interaction with ER+ cancer cells by a paracrine mechanism.

CTCF May Not Directly Regulate ERα mRNA Expression in the ER+ MCF7 Breast Cancer Cell Line

Introduction: CTCF is an evolutionally conserved 11-zinc finger protein factor involved in an array of processes whose deregulation could lead to cellular transformation. Through interactions with ERα binding regions and ERregulated genes, CTCF was shown to compartmentalize the cellular genome into domains. It also colocalized with ERα in MCF7 cells and had interactions with ERα during histone deacetylase recruitment and fork-head activity. A fast-running isoform was previously shown to be expressed in breast cancer tissue but not in normal breast tissue. It is not clear whether there is a regulatory relationship between CTCF and ERα in breast cancer. Aim: To determine whether CTCF expression regulated ERα expression in the ER+ MCF7 breast cancer cell line. Methods: MCF7 breast cancer cells were transfected with either CTCF expression vectors or siRNA against CTCF. Following CTCF over-expression and knock-down, changes in endogenous expression of ERα gene and protein expression were monitored by quantitative polymerase chain reaction (using MIQE guidelines) and western blot analysis respectively. Results: CTCF plasmid overexpression and siRNA knockdown was associated with cell rounding but with 96.4% and 95.7% cell viability respectively. Increase in CTCF mRNA on over-expression was associated with a rise in CTCF protein expression. siRNA knockdown of CTCF mRNA was accompanied by a corresponding decrease in CTCF protein expression. CTCF over-expression and knockdown appeared to inhibit the ability to detect ERα protein expression by western blotting. Neither the over-expression nor knockdown of CTCF altered ERα mRNA expression as detected by QPCR. Conclusion: Alterations in CTCF mRNA expression did not affect ERα gene expression in MCF7 cells suggesting that CTCF interactions with the estrogen receptor in breast cancer may not be mediated via direct regulation of ERα mRNA expression.

Apparent diffusion coefficient value measurements with diffusion magnetic resonance imaging correlated with the expression levels of estrogen and progesterone receptor in breast cancer: A meta-analysis.

Apparent diffusion coefficient (ADC) value measurement of nodes in diffusion-weighted images (DWI) has been widely used for diagnosis and differential diagnosis of human tumors. We evaluated whether the ADC provided by DWI varies according to the state of estrogen receptors (ER) and progesterone receptors (PR) in breast cancer (BC). English and Chinese electronic databases were searched for potentially relevant studies followed by a comprehensive literature search. Summary standardized mean difference (SMD) with 95% confidence interval (CI) was used for ER and PR category of ADC value with the use of the Z test. Final analysis from 6 eligible cohort studies between 2010 and 2012 were selected for inclusion. Overall estimates revealed that the mean ADC of ER-positive or PR-positive cancer was significantly lower than that of ER-negative or PR-negative breast cancer (ER- VS. ER+: SMD = 0.64, 95% CI: 0.02-1.27, P = 0.042; PR- VS. PR+: SMD = 0.45, 95% CI: 0.04-0.86, P = 0.032). Country-stratified analysis indicated the mean ADC of ER-positive cancer was significantly lower in China (SMD = 3.92, 95% CI: 2.22-5.62, P < 0.001). Further subgroup analysis by MRI machine type implied that ADC values may be a potential diagnostic indicator for PR levels in breast cancer only when using Non-Phillips 1.5T scanner (SMD = 0.88, 95% CI: 0.64-1.12, P < 0.001). ADC values vary significantly according to the ER and PR levels in BC patients, indicating that cancer heterogeneity affects imaging parameters. DWI could therefore be critical for clinical applications of ADC values.

Relationship Between Estrogen Receptor Co-regulators and Histological Grade in Estrogen-Dependent Invasive Breast Cancer

The study aims to assess the relationship between level expression co-regulators of estrogen receptor (SRC1, CBP/p300, NCoR, SMRT) in estrogen-dependent invasive breast cancer with histological grade. The other aims of study to evaluate the interaction between p53, Ki-67, Her-2/Neu expression and co-regulators with the histological grade. Analysis of these relationships will result in deeper understanding on the molecular basis of breast cancer incidence which can be associated with prognosis and prediction of the disease and evaluation of the targeted therapy in breast cancer. The co-regulators and p53, Ki-67, Her-2/Neu were examined using immuno-histochemical technique toward paraffin block of 85 patients with estrogen receptor (ER) α positive. Relationships between these targets and histological grade were analyzed. We observed that SRC1 was associated with a high degree of malignancy and NCoR had a significant correlation with a low degree of malignancy. Interaction of SRC1 and NCoR with p53, Ki-67 and Her-2/Neu is significantly associated with the high degree of malignancy. This study provided evidence that SRC1 and NCoR were the independent prognostic factors. SRC1 was associated with the high grade malignancy (poor differentiation and in the other hand, the NCoR was associated with well differentiation histopathology. High expression of p53, Ki-67 and Her2/Neu which interact with SRC1 and NCoR were associated with a high degree malignancy.

Gene-based analysis of the fibroblast growth factor receptor signaling pathway in relation to breast cancer in African American women: the AMBER consortium.

We conducted gene-based analysis in 26 genes in the FGFR signaling pathway to identify genes carrying genetic variation affecting risk of breast cancer and the specific estrogen receptor (ER) subtypes. Tagging single-nucleotide polymorphisms (SNPs) for each gene were selected and genotyped on a customized Illumina Exome Array. Imputation was carried out using 1000 Genomes haplotypes. The analysis included 3237 SNPs in 3663 breast cancer cases (including 1983 ER-positive, and 1098 ER-negative) and 4687 controls from the African American Breast Cancer Epidemiology and Risk consortium, a collaborative project of four large studies of breast cancer in African American women (Carolina Breast Cancer Study, Black Women's Health Study, Women's Circle of Health Study, and Multiethnic Cohort). We used a multi-locus adaptive joint (AdaJoint) test to determine the association of each gene in the FGFR signaling pathway with overall breast cancer and ER subtypes. The FGF1 gene was significantly associated with risk of ER-negative breast cancer (P = 0.001). The FGFR2 gene was associated with risk of overall breast cancer (P = 0.002) and ER-positive breast cancer (P = 0.002). The FGF1 gene affects risk of ER-negative breast cancer in African American women. We confirmed the association of the FGFR2 gene with risk of overall and ER-positive breast cancer. These results highlight the importance of the FGFR signaling pathway in the pathogenesis of breast cancer, and suggest that different genes in the same pathway may be associated with different ER breast cancer subtypes.

Surgery time interval and molecular subtype may influence Ki67 change after core needle biopsy in breast cancer patients.

BackgroundTo investigate the accuracy of core needle biopsy (CNB) in evaluating breast cancer estrogen receptor (ER), progesterone receptor (PR), HER2, and Ki67 status and to identify factors which might be associated with Ki67 value change after CNB.MethodsA retrospective study was carried out on 276 patients with paired CNB and surgically removed samples (SRS). Clinico-pathological factors as well as the surgery time interval (STI) between CNB and surgery were analyzed to determine whether there were factors associated with Ki67 value change after CNB. Five tumor subtypes were classified as follows: Luminal A, Luminal B-HER2-, Luminal B-HER2+, Triple Negative (TN), and HER2+. Ki67 value change was calculated as SRS minus CNB.ResultsMean STI after CNB was 4.5 (1-37) days. Good agreement was achieved for ER, PR, and HER2 evaluation between CNB and SRS. However, Ki67 expression level was significantly higher in SRS compared with CNB samples: 29.1 % vs. 26.2 % (P < 0.001). Both univariate and multivariate analysis demonstrated that STI and molecular subtype were associated with a Ki67 change after CNB. Luminal A tumors experienced more Ki67 elevation than Luminal B-HER2- diseases (6.2 % vs -0.1 %, P = 0.014). Patients with longer STI after CNB had a higher Ki67 increase: -1.1 % within 1-2 days, 2.1 % with 3-4 days, and 5.6 % more than 4 days, respectively (P = 0.007). For TN and HER2+ tumors, the Ki67 change was apt to be 0 with STI ≤ 4 days, while a >7 % Ki67 increase was noticed in patients with STI ≥ 5 days.ConclusionCNB was accurate in evaluating ER, PR, HER2, and molecular subtype status. Ki67 value significantly increased after CNB, which was associated with STI and molecular subtype. Further translational research needs to consider Ki67 changes following CNB among different breast cancer molecular subtypes.Electronic supplementary materialThe online version of this article (doi:10.1186/s12885-015-1853-1) contains supplementary material, which is available to authorized users.

RIME proteomics of estrogen and progesterone receptors in breast cancer.

Nuclear receptors play an important role in transcriptional regulation of diverse cellular processes and is also relevant in diseases such as cancer. In breast cancer, the nuclear receptors – estrogen receptor (ER) and progesterone receptor (PR) are classical markers of the disease and are used to classify breast cancer subtypes. Using a recently developed affinity purification MS technique (RIME) [1], we investigate the protein interactors of ER and PR in breast cancer cell lines upon stimulation by the ligands – estrogen and progesterone. The data is deposited at proteomeXchange (PXD002104) and is part of a publication [2] that explains the link between the two nuclear receptors and potential consequences of this in breast cancer. In this manuscript, we describe the methodology used and provide details on experimental procedures, analysis methods and analysis of raw data. The purpose of this article is to enable reproducibility of the data and provide technical recommendations on performing RIME in hormonal contexts.

Abstract 5046: Amphiregulin is a key effector of estrogen receptor in breast cancer

Abstract Estrogen is an essential hormone for mammary gland development and is a key driver of proliferation during the development of estrogen receptor positive breast tumors. The actions of estrogen are primarily mediated by its receptor, the ERα transcription factor, which regulates several hundred estrogen-responsive genes in breast cancer cells. However, despite much investigation, the identity of the key effectors of this proliferative signal in breast cancer remains unclear. Amphiregulin (AREG) is a ligand of the Epidermal Growth Factor Receptor. It is transcriptionally regulated by estrogen and is required for estrogen-dependent mouse mammary gland development. In this study, we have tested whether Amphiregulin is a key effector of estrogen in breast cancer. shRNA-mediated knockdown of Amphiregulin in MCF7 cells strongly attenuated ER+ breast cancer cell line growth in vivo. Conversely, expression of Amphiregulin from an estrogen-insensitive promoter allowed MCF7 xenografts to escape the therapeutic effects of tamoxifen. Thus, Amphiregulin expression is both necessary and sufficient for the proliferative response to estrogen in MCF7 cells in vivo, and downregulation of Amphiregulin in response to tamoxifen is required for a therapeutic benefit. After initially responding to endocrine therapy, many ER+ tumors progress to resistance to these therapies. Our model predicts that breast tumors which either (1) express AREG in an estrogen-insensitive manner or (2) have elevated levels of alterative ERBB family ligands, will be endocrine resistant. We present experimental and clinical evidence demonstrating that these features contribute to at least some examples of endocrine resistance. Firstly, in MCF7 cells selected for resistance to fulvestrant, we show that AREG expression is no longer regulated by estrogen or its antagonists, but the cells remain AREG-dependent. Secondly, in a series of 52 ER+ breast cancer patients treated with neo-adjuvant letrozole, we show that the downregulation of Amphiregulin in response to endocrine therapy observed in our mouse studies is recapitulated in human breast cancer patients, and that tumors in which alternate ERBB ligands (TGFalpha, Epiregulin, and Neuregulins 1 &amp; 2) are expressed at high levels are least likely to respond to letrozole. In summary, these data underline the importance of ERBB signaling in estrogen receptor positive breast cancer and implicate Amphiregulin as the primary ERBB ligand in mediating the effects of estrogen in these tumors. Citation Format: Esther A. Peterson, Natasha Chandiramani, Evelyn J. Aranda Jaque, E. Charles Jenkins, Paraic A. Kenny. Amphiregulin is a key effector of estrogen receptor in breast cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5046. doi:10.1158/1538-7445.AM2015-5046

Abstract 2790: Gene-based analysis of the fibroblast growth factor receptor signaling pathway identifies an association of the FGF1 gene with risk of estrogen receptor-negative breast cancer: The AMBER consortium

Abstract Fibroblast growth factors (FGFs) and their receptors (FGFRs) play key roles in several cellular processes such as differentiation, proliferation, migration and survival. Deregulation of the FGFR signaling pathway has been associated with human cancer including breast cancer, and GWAS-identified polymorphisms in the FGFR2 gene have been associated with risk of both overall and estrogen receptor (ER)-positive breast cancer. We conducted gene-based analysis in 26 genes in the FGFR signaling pathway to identify genes carrying genetic variation affecting risk of breast cancer and the specific ER subtypes. Tagging single nucleotide polymorphisms (SNPs) at ±10 kb of each gene were selected and genotyped in a customized Illumina Exome Array. Imputation was carried out using 1000 Genomes haplotypes. The analysis included 9,264 SNPs in 3,663 breast cancer cases (including 1,983 estrogen receptor-positive (ER+), and 1,098 estrogen receptor-negative (ER-)) and 4,687 controls from the African American Breast Cancer Epidemiology and Risk (AMBER) consortium, a collaborative study of four of the largest studies of breast cancer in African American women (Carolina Breast Cancer Study, Black Women's Health Study, Women's Circle of Health Study, and Multi-Ethnic Cohort). We used the adaptive rank-truncated product (ARTP) method implemented in R-package PIGE to determine the association of each gene in the FGFR signaling pathway with overall breast cancer, and ER subtypes. Analyses were adjusted for principal components of genetic variation to control for population stratification, age, geographic region of residence, study, and source of DNA. An alpha level of 0.002 ( = 0.05/26 genes) was used to determine statistical significance at the gene-wide level. After adjustment for multiple testing the FGF1 gene was associated with risk of ER-negative breast cancer (p = 0.001). The FGF1 gene codes for the fibroblast growth factor 1. Genetic variation in this gene has been reported to be associated with risk of ovarian cancer and with breast cancer survival. As expected, the FGFR2 gene was associated with risk of overall breast cancer (p = 0.001) and ER-positive breast cancer (p = 0.002). In summary, we found that the FGF1 gene affects risk of ER-negative breast cancer in African American women, and we confirmed the association of the FGFR2 gene with risk of overall and ER-positive breast cancer. These results highlight the importance of the FGFR signaling pathway in the pathogenesis of breast cancer, and suggest that different genes in the same pathway may be associated with different ER breast cancer subtypes. Citation Format: Edward A. Ruiz-Narvaez, Stephen Haddad, Christopher A. Haiman, Song Yao, Lara E. Sucheston-Campbell, Jeanette T. Bensen, Kathryn L. Lunetta, Andrew F. Olshan, Christine B. Ambrosone, Julie R. Palmer. Gene-based analysis of the fibroblast growth factor receptor signaling pathway identifies an association of the FGF1 gene with risk of estrogen receptor-negative breast cancer: The AMBER consortium. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2790. doi:10.1158/1538-7445.AM2015-2790

Immunohistochemical Profile of Breast Cancer Patients at a Tertiary Care Hospital in New Delhi, India

To assess the immunohistochemical expression of estrogen receptor (ER), progesterone receptor (PgR) and human epidermal growth factor receptor-2 (HER2) neu receptor in breast cancer and their associations with various clinicopathological characteristics. This is a retrospective analysis of women who presented with primary, unilateral breast cancer in the Department of Medical Oncology at Rajiv Gandhi Cancer Institute and Research Centre, Delhi, India during the period from January 2008 to December 2011. Data were retrieved from the medical records of the hospital including both early and locally advanced cancer cases. ER, PgR and HER2neu expression in these patients was assessed and triple negative patients were identified. Associations of triple negative and non-triple negative groups with clinicopathological characteristics were also evaluated. A total of 1,284 women (mean age 52.1 years, 41.9% premenopausal) were included in the analysis. Hormone receptor positivity (ER and/or PgR) was seen in 63.4% patients, while 23.8% of tumors were triple negative. Only 23.0% were HER2 positive. Around 10.0% of tumors were both ER and HER2 positive. ER and PgR positivity was significantly associated with negative HER2 status (p-value<0.0001). Younger age, premenopausal status, higher tumor grade, lymph node negativity, advanced cancer stage, and type of tumor were strongly associated with triple negativity. Significantly, a smaller proportion of women had ductal carcinoma in situ in the triple negative group compared with the non-triple negative group (35.6% versus 60.8%, p-value<0.01). The present analysis is one of the largest studies from India. The majority of the Indian breast cancer patients seen in our hospital present with ER and PgR positive tumors. The triple negative patients tended to be younger, premenopausal, and were associated with higher tumor grades, negative lymph nodes status and lower frequency of ductal carcinoma in situ.

PIK3CA: a Target or a Marker in Breast Cancers

The phosphoinositide 3 kinase (PI3K)/Akt pathway is frequently aberrantly activated in breast cancer and, basing on preclinical data, leads to cell growth and tumor proliferation. PI3K pathway activation has been suggested as a potential driver of resistance to endocrine and anti-HER2 therapies. Large genomic studies have observed that the PIK3CA gene is mutated in up to 40 % of breast cancers, mainly estrogen receptor- and HER2-positive. Some strategies targeting the PI3K/Akt/mTOR axis, in particular co-targeting the estrogen receptor and mTOR in endocrine resistant estrogen receptor-positive breast cancer, have proven successfully this hypothesis. Pan-class I PI3K inhibitors and more selective p110α inhibitors are currently under investigation in different clinical settings. In this review, clinical data on the prognostic and predictive role of PIK3CA mutations in different breast cancer subtypes are covered, and a picture on the current clinical research on PI3K inhibitors is provided.

Abstract A11: Crosstalk between mTORC1 and estrogen receptor in breast cancer

Abstract Approximately two thirds of all breast cancer cases are estrogen receptor (ER) positive, which underscores the dependence of cancer cells on estrogen for growth and survival. However, resistance to endocrine therapy develops in most cases. mTORC1 (the mechanistic target of rapamycin complex 1) is a critical node of estrogen signaling in the cell, however the mechanism of estrogen activation of mTORC1 is not well understood. We have previously demonstrated that mTORC1 promotes growth factor-mediated ER activation by phosphorylating ERα on Ser167. This phosphorylation, which is mediated by the mTORC1 effector kinase S6K1, is important for ERα dimerization, DNA binding and transcriptional activity, is associated with endocrine resistance and correlates with therapy response. Moreover, ERα promotes expression of S6K1, generating a feed-forward positive activation loop. Our current efforts are focused on fully understanding the nature and mechanism of the relationship between mTORC1 and estrogen pathways. Our data indicate that mTOR, raptor and ER form a complex whereby ER directly interacts with raptor. Moreover, this interaction is stimulated by estrogen as seen by co-immunoprecipitation analysis. We additionally found that ER and raptor co-localize to the nucleus upon estrogen stimulation, where they interact as detected by both immunofluorescence and cellular fractionation experiments. Our current efforts are focused on understanding the role of this interaction and the mechanism of estrogen mediated localization of raptor to the nucleus. We are also investigating the role of raptor and estrogen receptor interaction in endocrine therapy treatment and resistance. Citation Format: Anya Alayev, Rachel S. Salamon, Marina K. Holz. Crosstalk between mTORC1 and estrogen receptor in breast cancer. [abstract]. In: Proceedings of the AACR Special Conference: Targeting the PI3K-mTOR Network in Cancer; Sep 14-17, 2014; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(7 Suppl):Abstract nr A11.

Study of Positive Estrogen Receptor Breast Cancer Survival of Patients Treated at the ShohadaHospital in Tajrish, Tehran

Study of Positive Estrogen Receptor Breast Cancer Survival of Patients Treated at the ShohadaHospital in Tajrish, Tehran

Sex hormone-dependent tRNA halves enhance cell proliferation in breast and prostate cancers

Sex hormones and their receptors play critical roles in the development and progression of the breast and prostate cancers. Here we report that a novel type of transfer RNA (tRNA)-derived small RNA, termed Sex HOrmone-dependent TRNA-derived RNAs (SHOT-RNAs), are specifically and abundantly expressed in estrogen receptor (ER)-positive breast cancer and androgen receptor (AR)-positive prostate cancer cell lines. SHOT-RNAs are not abundantly present in ER(-) breast cancer, AR(-) prostate cancer, or other examined cancer cell lines from other tissues. ER-dependent accumulation of SHOT-RNAs is not limited to a cell culture system, but it also occurs in luminal-type breast cancer patient tissues. SHOT-RNAs are produced from aminoacylated mature tRNAs by angiogenin-mediated anticodon cleavage, which is promoted by sex hormones and their receptors. Resultant 5'- and 3'-SHOT-RNAs, corresponding to 5'- and 3'-tRNA halves, bear a cyclic phosphate (cP) and an amino acid at the 3'-end, respectively. By devising a "cP-RNA-seq" method that is able to exclusively amplify and sequence cP-containing RNAs, we identified the complete repertoire of 5'-SHOT-RNAs. Furthermore, 5'-SHOT-RNA, but not 3'-SHOT-RNA, has significant functional involvement in cell proliferation. These results have unveiled a novel tRNA-engaged pathway in tumorigenesis of hormone-dependent cancers and implicate SHOT-RNAs as potential candidates for biomarkers and therapeutic targets.

UPLC-qTOF-MS chemometric strategy to identify bioactive constituents from Garcinia oblongifolia

Garcinia oblongifolia is a well-known medicinal plant from southern China, with edible fruits. However, the phytochemistry and bioactivity of the different parts of G. oblongifolia are still not well studied. We developed a strategy to identify potential bioactive compounds from the leaves, branches, and fruits of G. oblongifolia by combining bioactivity analysis with UPLC-qTOF-MS based chemometrics. Preliminary screening with human breast cancer estrogen receptor positive MCF-7 cells showed that G. oblongifolia branch extracts influenced cell growth in a dose-dependent fashion by causing a unique pattern of vacuolization, which was not observed with the leaf or fruit extracts. Cytotoxicity and cell proliferation studies are ongoing in order to further understand the difference in activity of the three extracts. The branch extract also showed strong antioxidant activity in DPPH and ABTS assays. UPLC-qTOF-MS combined with untargeted PCA and OPLS-DA analysis was conducted to analyze and compare the three extracts, and 12 compounds including 2 bioactive xanthones and 4 potential biomarkers were identified as the marker compounds for branches. Imaging and antioxidant results indicate that the branch extract exhibits greater activity than the leaf and fruit extracts. These findings provide a useful strategy to analyze extracts to find potential biomarkers from different parts of medicinal plants.

Erratum to: Quality assessment of estrogen receptor and progesterone receptor testing in breast cancer using a tissue microarray-based approach

Erratum to: Quality assessment of estrogen receptor and progesterone receptor testing in breast cancer using a tissue microarray-based approach