bluuebunny/crossref_metadata_2025_split huggingface dataset:
P1-04-02: In Vitro Qualification and Quantification of Murine Mammary Stem/Progenitor Cells.
Authors: Dong Q , Wang D , Bandyopadhyay A , Liu Z , Yu L , Gao H , Moncada K , Huang C , Walter CA , Sun L-Z 
Published: June 2012

Abstract
Increasing evidence suggest that tumors with a cell origin of more basal or stem-like sources are often highly metastatic and associated with poor prognosis. Identification of the cell of origin thus has important implications for development of new preventive and therapeutic approaches. To identifying the cells of origin of various breast cancers, understanding the normal cellular hierarchy within the breast tissue is an important prerequisite. However, current understanding of normal mammary stem/progenitor cell is limited due to the lack of a robust in vitro assay. The newly developed cell surface markers (CD24+CD49fhi) can only be used for low percent of enrichment. The only gold standard assay for functional evaluation of stem cell property is the in vivo transplantation of cleared mammary fat pad assay, yet this assay is expensive, time consuming, and requires highly trained skills, and thus cannot be used routinely for experiments. The goal of our study is thus to develop a robust in vitro assay to qualify and quantify murine mammary stem/progenitor cells. Our rationale lies on our recent findings of in vitro study of different fractions of murine stem/progenitor cells. When we use isolated primary epithelial cells for in vitro mammosphere formation, we found that stem cell enriched fraction and progenitor cell enriched fraction both formed very small mammospheres (≤ 50 μm) and these spheres appear to be of clonal origin (one cell gives rise to one sphere). When we plated these small spheres into 3D extracellular matrix for colony formation, however, they gave rise to two distinct structures: stem-enriched fraction generated predominately solid structure while progenitor-enriched fraction is dominated by hollow structures. Previous studies have linked the solid structure to the basal/myoepithelial lineage and the hollow structure to the luminal lineage. We thus suspected that the small mammospheres derived from the stem or progenitor enriched fractions could be originated from single stem or progenitor cell, and the number of spheres could indicate the number of original stem/progenitor cells within these enriched fractions. Subsequent in vivo transplantation with single sphere or single solid structure cultured in 3D extracellular matrix derived from green fluorescent protein transgenic mice proved that single sphere or 3D solid structure can repopulate the gland-free mammary fat pad. To conclude, the in vitro mammosphere formation in combination with subsequent differentiation in 3D extracellular matrix can be used as a robust in vitro assay for qualification and quantification of murine mammary stem/progenitor cells. This in vitro assay will greatly facilitate our understanding of genes regulate stem cell self-renewal, proliferation, differentiation as well as mechanisms keeping them at quiescent state within the niche.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-04-02.
P1-04-07: Poly (ADP-Ribose) Polymerase-1 (PARP-1) Is Overexpressed in Human Breast Cancer Stem Cells: Results from a Proteomic-Based Approach.
Authors: Gilabert M , Ginestier C , Audebert S , Pophillat M , Toiron Y , Birnbaum D , Borg J-P , Charafe-Jauffret E , Gonçalves A 
Published: June 2012

Abstract
Introduction: Cancer stem cells (CSC) have been increasingly recognized as playing a major role in various fields of breast tumor biology including carcinogeneis, metastasis and resistance to cytotoxic drugs and radiotherapy. Identification of protein biomarkers associated with breast CSC may help understanding CSC biology as well as identifying novel diagnostics and specific therapeutic targets. 2-D Fluorescence Difference Gel Electrophoresis (2-D DIGE) is a method that labels protein samples with fluorescent dyes before 2-D electrophoresis, enabling accurate analysis of differences in protein abundance between samples.
Methods: Using flow cytometry-based ALDEFLUOR assay (ALD), we isolated CSC-enriched (ALD-positive) and non CSC-enriched (ALD-negative) cell populations of MDA-MB-453, a human breast cancer cell line. Total proteins were extracted from both fractions using urea-based buffer and subjected to 2D-DIGE. Differentially expressed spots were excised, proteins were gel-extracted, digested and identified using MALDI-TOF MS (Ultraflex, Brucker Daltonics, Billerica, USA)
Results: 2D-DIGE revealed differential expression of various protein spots between ALD-positive and ALD-negative MDA-MB-453 cells. MALDI-TOF MS analysis allowed identification of 11 differentially expressed proteins, among which 7 were down-regulated and 4 were up-regulated in ALD-positive MDA-MB-453 cells, including Poly (ADP-ribose) polymerase-1 (PARP-1). Overexpression of PARP-1 in MDA-MB-453 cells was further confirmed by western blot using specific monoclonal antibody and such an observation was extended to 4 additional human breast cancer cell lines including HCC1937, MDA-MB-436, SUM149 and SUM159. These 5 human breast cancer cells were found to display a limited short-term sensitivity (within the micromolar range) to olaparib, a specific PARP-1 inhibitor. However, a negative correlation was found between the level of overexpression and the ability of olaparib to inhibit the growth of ALD-positive cells. Conclusion: A proteomic-based approach revealed that PARP-1 was up-regulated in ALD-positive, CSC-enriched from various human breast cancer cell lines. Such an overexpression may contribute to clinical resistance to PARP-inhibitors.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-04-07.
P1-04-09: Biphasic Effects of Docetaxel and Hedgehog Signaling Antagonists on Breast Cancer Tumor-Initiating Cells In Vivo.
Authors: Zhang X , Moraes RC , Landis MM , Wu M-F , Hilsenbeck SG , Cairo MM , Toftgar R , Chang JC , Lewis MT 
Published: June 2012

Abstract
Recent data suggest the existence of a subset of breast cancer cells variously termed cancer stem cells, tumor-initiating, or tumor-propagating cells, that are capable of self-renewal and of regenerating tumors upon transplantation that are biologically consistent with the tumor of origin. These cells appear to be intrinsically resistant to systemic chemo- and radiation therapies and may therefore be responsible for treatment resistance, and disease recurrence. Several signal transduction networks have been implicated in normal and malignant stem cell self-renewal. These include those of the Hedgehog, Notch, Wnt, EGF, FGF families of ligands. Antagonists of these networks have become attractive targeted therapeutic agents. In this study, we evaluated two different Hedgehog signaling antagonists, one targeting Smoothened (the main membrane effector of activated signaling) and one targeting GLI1/2 (the two transcription factors mediating ligand response), for their ability to shrink patient-derived xenograft tumors and to affect the number or function of breast tumor-initiating cells in vivo. Both antagonists showed little effect as single agents, but could augment tumor shrinkage by docetaxel. However, these effects were only observed in those models showing evidence of canonical SMO/GLI-mediated signaling. In dilutional transplantation assays, both SMO or GLI targeted agents have a biphasic effect on the behavior of the tumor-initiating population such that large cell numbers yielded few tumors while intermediate cell numbers yielded tumors at a comparable rate as controls. These data suggest that combination therapy alters the functional state of stem cells in the context of larger cell numbers rather than targeting the tumor-initiating cell directly. These data therefore have significant relevance for the interpretation of ongoing clinical trials of hedgehog signaling inhibitors in solid tumors, including breast cancer.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-04-09.
P1-07-10: Validation of a Diagnostic Molecular Signature (EHT Dx14) on Fine-Needle Aspirate Samples from Breast Tumors.
Authors: Delaloge S , André F , Fehlbaum P , Sol O , Vielh P 
Published: June 2012

Abstract
Background: A 1228-probeset molecular classifier (EHT Dx14) able to discriminate benign breast lesions from breast adenocarcinoma with a 96% performance was previously identified in a panel of 71 fine-needle aspirate (FNA) samples of nodular breast lesions collected at Institut Gustave Roussy (IGR). The microarray which enabled the signature identification was based on the genomewide RNA analysis using the ExonHit's SpliceArray™ technology. The objective of the current study was to validate the performance of the EHT Dx14 molecular classifier on an independent cohort of FNA samples stored at the Centre de Ressources Biologiques at IGR.
Patients and methods: The samples were collected from women undergoing investigations for suspicious nodular breast lesions classified BIRAD ACR 4 or 5 on mammogram and/or ultrasonography. The morphological cytological analysis of FNA samples classified the lesions as either benign, malignant or indeterminate. All samples were associated with a definite clinico-pathological diagnosis of the breast lesions. The first part of the study aims at confirming the sensitivity, specificity and overall performance of EHT Dx14 among lesions clearly classified by morphological cytology. The second part aims at establishing its performance among lesions with indeterminate cytological results.
Results: In the first part of the study, the EHT Dx14 transcriptomic signature was applied on a set of 94 FNA consecutive samples categorized as benign (n=47) or adenocarcinoma (n=47) on cytology. The benign/malignant status of the lesions was confirmed by subsequent investigations or follow-up. Results of EHT DX-14 assessment of the samples were respectively 97.9% (95%CI: [88.7%-99.9%]) for sensitivity and 91.5% (95%CI: [79.6%-97.6%]) for specificity. Results on indeterminate FNA samples are being investigated in the second part of the study.
Conclusion: This study did confirm the high performance of EHT Dx14 signature in identifying malignant from benign breast lesions in clinically suspect lesions. EHT Dx14 may provide adequate biological diagnosis in the absence of capability of morphological evaluation.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-07-10.
P1-07-13: Efficiency of a Laboratory Developed HER2 FISH Test on Circulating Tumor Cells.
Authors: Mayer JA , Pham T , Wong KL , Scoggin J , Sales EV , Clarin T , Pircher TJ , Mikolajczyk SD , Cotter PD , Bischoff FZ 
Published: June 2012

Abstract
INTRODUCTION: Most circulating tumor cell (CTC) platforms rely on EpCAM for capture and cytokeratin (CK) for detection. However, an important population of cells that are CK-negative (i.e. cells with epithelial-mesenchymal transition (EMT) phenotype) will be missed. We report a new strategy to efficiently isolate a more heterogeneous population of CTCs using an antibody cocktail.
METHODS: In the first prospective study, blood (20 mL) was collected from 89 patients diagnosed with various late stage metastatic/recurrent cancers (breast, CRC, lung, prostate) following IRB approval. PBMCs were incubated with either EpCAM alone or a mixture of 10 capture antibodies to target both epithelial and mesenchymal cells. CTCs were subsequently captured in the OncoCEE™ channels and detected with cytokeratin (CK) and CD45. A second prospective IRB approved study involving 54 patients diagnosed with late stage metastatic/recurrent breast cancer was performed using similar detection strategies (CK cocktail mixture and anti-CD45) with the addition of HER2 FISH to determine amplification status among captured CK+/CD45- and CK-/CD45-cells.
RESULTS: In the first study, overall detection of CK+ cells was 83% with EpCAM alone and 93% with antibody cocktail. In addition, a median of 0.4 CK+ cells/mL and 1.0 CK+ cells/mL was observed using EpCAM and antibody cocktail, respectively. In the second study, CK+/CD45- cells were detected in 43 of 54 cases (80%). Among the 43 cases in which CK+/CD45- cells were detected, high concordance (93%) in HER2 status between primary tumor and CTCs was observed with HER2 amplification noted in both CK+/CD45- (50%) and CK-/CD45- (50%) cells.
CONCLUSIONS: We have developed a novel and robust method for CTC enumeration that utilizes a cocktail of antibodies for the detection of a heterogeneous (CK+ and CK-) population of CTCs. Our findings suggest an important population of CK- cells is being missed by current stain criteria in breast cancer patients. Data also demonstrate that recovery of CTCs from peripheral blood using the OncoCEE™ platform is efficient and suitable for FISH-based laboratory testing.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-07-13.
P1-08-14: Arsenic Methylation Is Associated with Breast Cancer Risk in Northern Mexico.
Authors: López-Carrillo L , Hernández-Ramírez U , Torres-Sánchez L , Gandolfi JA , Ornelas-Aguirre JM , Cebrián ME 
Published: June 2012

Abstract
Background: Arsenic (iAs) exposure has been associated with several types of cancer. However, most studies to date have not yet implicated iAs as a cofactor for breast cancer (BC). BC incidence and mortality are 3-fold higher in Northern Mexico (NM) than in the rest of the country. iAs levels in drinking water are a source of concern since they have been above international standards. We hypothesized that iAs exposure and individual Arsenic-methylation ability are potential cofactors for BC risk.
Material and Methods: We investigated 840 BC incident cases and 973 controls from a population-based case-control study performed in NM. Women were directly interviewed about dietary and reproductive BC covariables. iAs metabolites in urine were determined by HPLC/ICP-MS. Methylation capacity was assessed by calculating the percentage of iAs species and primary [MMA(V)/(As(III)+As(V)] (PMI) and secondary [DMA(V)/MMA(V)] methylation indexes (SMI).
Results: The range of total urinary Arsenic was 0.4−303.9 ug/L. Most women (91%) had values above 50 ugAs/L.%MMA(V) was significantly higher in BC cases while%DMA(V) was significantly lower. PMI was positively associated with BC (OR T3vsT1=1.47; CI95=1.17−1.84; p for trend=0.001), while SMI was negatively associated (OR T3vsT1=0.54; CI95=0.42−0.68; p for trend&lt;0.001). Discussion: As exposure may pose a risk for BC, particularly in women with higher capacity to methylate iAs to MMA(V) and lower capacity to further methylate MMA(V) to DMA(V). This is consistent with studies indicating that the proportion of MMA(V) in urine was positively associated whereas that of DMA(V) was inversely associated with the risk of skin, bladder and lung cancer. Further research is needed about the temporal relationships between disease and methylation capacity and the presence of potential association modifiers, including environmental and genetic factors involved in one carbon metabolism.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-08-14.
P1-08-18: Aspirin Exposure and Nodal Status at Diagnosis in Women with Stage I-III Breast Cancer.
Authors: Barron TI , Sharp L , Bennett K , Visvanathan K 
Published: June 2012

Abstract
Background: The recent Nurses’ Health Study reported an association between aspirin use and a reduction in breast cancer (BC) recurrence and BC-specific mortality. It has been suggested based on preclinical data that these effects may be due to the inhibition of tumor invasion and metastasis by aspirin. To test this hypothesis we examined the association between aspirin exposure prior to BC diagnosis and nodal involvement at diagnosis.
Methods: A retrospective analysis was conducted using linked pharmacy claims and cancer registry data from the National Cancer Registry Ireland. Women with an incident diagnosis of stage I-III BC between 2001–2006 and no prior invasive cancer were included. Women with a prescription for aspirin at any time in the year prior to diagnosis were defined as exposed. Multivariate logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) for (a) N0 disease; (b) N1 disease (c) N1/2/3 disease at diagnosis in aspirin exposed (overall exposure & exposure quartiles by duration of use) versus unexposed women. All analyses were adjusted for age, tumor size/grade, ER, PR and HER2 receptor status. Analyses were repeated including women with stage IV BC at diagnosis. Survival analyses are ongoing.
Results: 4212 women with stage I-III BC at diagnosis were identified. 1086 (25.8%) had a supply of aspirin available to them in the year prior to diagnosis (median dose 75mg, interquartile range 75mg, 75mg). Women taking aspirin were older than those who did not (74.3 yrs/64.4 yrs p&lt;0.05). There was no difference in tumor sizes, grade, ER, PR or HER2 receptor status between exposed and unexposed women. In the multivariate logistic regression analysis aspirin exposure was associated with significantly increased odds of an N0 tumor (Table 1; OR 1.27 95%CI 1.09, 1.48) and significantly decreased odds of an N1 or N1/2/3 tumor. Additionally, women taking aspirin for &gt;95% of the year prior to diagnosis had the highest odds of an N0 tumor (Table1; OR 1.50 95%CI 1.14, 1.97). There was no difference in the odds of an N0 tumor for women taking aspirin for &lt;40% of the prior year (OR 1.01 95%CI 0.78, 1.31). Inclusion of stage IV BC (n=789) in the analysis did not significantly alter these results.

Discussion: This study demonstrates a significant association between aspirin use in the year prior to BC diagnosis and the degree of nodal involvement at diagnosis. Furthermore there was a clear dose-response relationship between increasing duration of exposure and nodal status. These associations are unlikely to be due to confounding by healthy user/adherer behaviors as tumor sizes did not vary significantly between unexposed and exposed women, or across quartiles of exposure duration.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-08-18.
P1-09-01: Effect of Obesity on Gene Expression in Invasive Breast Tumors.
Authors: Ellsworth RE , Croft DT , Ellsworth DL , Shriver CD 
Published: June 2012

Abstract
Background: Obesity is a risk factor for breast cancer in postmenopausal women and weight gain after diagnosis is associated with decreased survival and less favorable clinical characteristics such as greater tumor burden, higher grade, and poor prognosis, regardless of menopausal status. Despite the negative impact of obesity on clinical outcome, molecular mechanisms influencing breast cancer prognosis remain elusive.
Methods: Postmenopausal women with invasive breast cancer (n=20) in the Clinical Breast Care Project who were obese at diagnosis (BMI ≥30) were matched by age, stage, ER status, HER2 status, and tumor grade to women who maintained a healthy weight (BMI = 18.5−24.9). Sections of pure invasive carcinoma were obtained by laser microdissection from flash-frozen or OCT embedded sections. Gene expression data using U133 2.0 microarrays was generated to compare genome-wide patterns of expression in breast tumors between obese and normal-weight patients. Data were analyzed using Partek Genomics Suite.
Results: Principal Component Analysis accurately clustered the specimens into two groups, healthy weight or obese. Using a false-discovery rate (FDR) p-value &lt;0.05 with a minimum 2.0-fold change of expression, 119 probes from 106 genes were differentially expressed, with 35 genes expressed at significantly higher levels and 71 at significantly lower levels in tumors from obese women compared to those from healthy-weight patients. Hierarchical clustering using these 119 probes reliably partitioned all samples as healthy-weight or obese. Genes differentially expressed include lower expression of several members of the histone cluster 1 family, APOD and IGF1, and higher expression of FABP7, members of the major histocompatibility complex and LTF in tumors from obese women.
Conclusions: Invasive breast tumors from obese women are genetically different from those of healthy-weight women. Altered gene expression may affect tumor cell proliferation and survival, contributing to aggressive phenotypes and altered immune response. These underlying molecular differences may contribute to the less favorable prognosis observed in obese women with breast cancer.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-09-01.
P1-12-05: Complete Pathological Response of Ductal Carcinoma In Situ after Treatment with Neoadjuvant Herceptin.
Authors: Chalmers CR , Mallon EA , Touqan N , Horgan KJ , MacPherson I , Doughty JC 
Published: June 2012

Abstract
Introduction: The introduction of neo-adjuvant herceptin has led to pathological complete response rates of up to 60% in patients with breast cancer. The traditional (NSABP) definition of pathological complete response includes cases demonstrating residual DCIS and little is known about the effects of neo-adjuvant herceptin in this situation. Current evidence suggests that DCIS is chemo-resistant, but it has also been shown that DCIS is more likely to be HER-2 positive than primary cancer.
Results: We describe six patients who received neo-adjuvant chemotherapy and herceptin for biopsy-proven, node-positive, large breast cancers either with an extensive component of concomitant DCIS or a separate DCIS focus. Neo-adjuvant treatment did not result in any changes in the pattern of mammographic calcification seen pre-operatively (Figure 1 a-c), however histopathology of all six specimens showed ductal spaces containing macrophages and calcification but no residual lining epithelium, features consistent with pathological complete response of the DCIS component (Figure 1d). Figure 1: Pathologically complete response of DCIS after neo-adjuvant treatment with herceptin. (a) Pre-treatment mammogram (b) Post neo-adjuvant chemotherapy and herceptin mammogram showing resolution of the mass effect of the primary cancer and unchanged residual mammographic calcification associated with the extensive DCIS component (c) Wire-localised specimen demonstrating excision of calcification (d) Histopathology of the same specimen showing calcium-filled ducts and no residual lining epithelium. Discussion: In conclusion, neo-adjuvant herceptin is associated with complete pathological response of both breast cancer and DCIS. The presence of unchanged persistent mammographic calcification in known regions of DCIS after treatment complicates any role of mammographic surveillance in this group and raises the question of optimal surgical management in the future management of these individuals.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-12-05.