bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract P4-12-03: Role of primary tumor molecular characteristics in identifying relapses in HER2-positive breast carcinomas adjuvantly treated with trastuzumab
Authors: Triulzi T , De Cecco L , Giussani M , Canevari S , Carcangiu ML , Menard S , Campiglio M , Tagliabue E 
Published: August 2014

Abstract
Trastuzumab, a recombinant humanized monoclonal antibody directed to the HER2 protein, has shown survival benefits in women with HER2-positive breast cancer, and treatment is now FDA-approved in combination with chemotherapy. Nonetheless, some patients relapse after treatment, underscoring the need to identify patients for whom chemotherapy + trastuzumab is adequate versus patients requiring additional drugs. To search for factors predictive of relapse in HER2-positive breast carcinoma patients treated adjuvantly with trastuzumab, we conducted gene expression profiling analysis in 53 cases selected among a cohort of 243 patients (32 of whom relapsed) treated in the clinic with chemotherapy + trastuzumab in our institute during 2006-2009, with median follow-up of 32 months; the 53 cases comprised 23 of the relapsed and 30 of the non-relapsed patients with similar clinico-pathological characteristics (size, lymph node involvement and estrogen receptor positivity) for whom sufficient material was available. RNA extracted from formalin-fixed, paraffin-embedded (FFPE) was profiled using HumanHT12_v4 wgDASL expression BeadChips (Illumina). A Cox's proportional hazard model was used to estimate the association between gene expression and relapse-free survival (RFS), and a multivariate permutation test was used to check the proportion of false discoveries. Analysis identified 330 probes corresponding to 308 unique genes as significantly associated to RFS (a&lt;0.005; permutation test p&lt;0.01), showing an enrichment for gene ontology biological processes such as cell cycle regulation of immune cell proliferation and activation, cytoskeleton organization, ER pathway and ion transport.
We also tested the feasibility of developing a predictive model including the gene expression data. Based on 10-fold cross-validation, our model was able to stratify patients into two groups (high and low risk), with a 4-year RFS probability of 14.5% in high-risk versus 87% in low-risk tumors (HR = 8.33, 95% CI = 3.53-18.18, p&lt;0.0001). To test whether this signature identifies patients with intrinsic poor prognosis independent of trastuzumab treatment, we conducted in silico analysis on a dataset containing 144 HER2-positive breast carcinomas treated with chemotherapy alone; results revealed an inverse association between risk groups and prognosis, with an overall survival probability of 83% in our high-risk group and 63% in the low-risk group (HR = 0.60, 95% CI = 0.37-0.94, p = 0.0249).
Together, our results suggest the usefulness of molecular characteristics of primary tumors as indicators of early relapse in patients treated adjuvantly with trastuzumab and as tools to identify patients for whom additional treatments are required.
Supported by AIRC.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-12-03.
Abstract P4-12-21: Trastuzumab cardiac toxicity and HER2 polymorphism: A case-control study
Authors: Mailliez A , Dumont A , Bonneterre J 
Published: August 2014

Abstract
Background: Gene polymorphisms of HER2 have been identified. Their impact on the risk of breast cancer, the response and the toxicity of anti HER2 treatments have been studied. According to a small report of Beauclair (2007), the polymorphism at codon 655 of the HER2 gene may represent a risk factor for cardiotoxicity induced by Trastuzumab (T). In this study, we evaluated the incidence of the Val655Ile polymorphism in (neo)adjuvant breast cancer patients (pts) with cardiac toxicity and in matched patients without cardiac toxicity.
Methods: 40 HER2 positive breast cancer pts treated between 2008 and 2011 by (neo)adjuvant sequential chemotherapy plus T developed a cardiac toxicity. Definition of cardiac toxicity was a 10% absolute decrease in LVEF (Left Ventricular Ejection Fraction) or a decrease in LVEF to a threshold value of &lt;50%. 84 pts without cardiac toxicity were matched according to age, received dose of anthracyclin and T, BMI and cardiac risk factors. Polymorphism of Her2 gene in codon 655 was searched by PCR on lymphocyte DNA from blood samples in this population and in the control group. Genomic DNA was extracted from EDTA blood samples (300ml) on the MagNa Pure Compact instrument. The HER2 Ile655Val (rs1163201) polymorphism was detected by sequencing using a 3730 DNA Analyser.
Results: In the cardiac toxicity group 2,5% (1 patient) presented a genotype Val/Val at HER2 codon 655, 40% (16) were heterozygous (Ile) and 57,5% (23) had the wild type. In the control population, the incidence was respectively 3,6% (3 pts), 36,9% (31) and 59,5% (50). No differences were found between the both groups (p = 0,91).
Conclusions: The incidence of mutated, heterogeneous and wild type genotype was similar to the literature. We could not confirm the Val allele at HER2 codon 655 as a risk factor of cardiotoxicity. HER2 polymorphism cannot be used in clinical practice to predict the risk of cardiac toxicity of T.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-12-21.
Abstract P4-15-09: An exploratory analysis of inactivation of PI3K/AKT/mTOR signaling pathway using neoadjuvant BKM120 in PI3KCA mutated early breast cancer
Authors: Estevez LG , Suarez A , Calvo I , Fernandez-Abad M , Perea S , Hidalgo M 
Published: August 2014

Abstract
Background: The PI3K/AKT/mTOR signaling pathway plays a key role for the growth and survival of breast cancer cells and aberrations such as phosphatidylinositol-3-kinase (PI3KCA) mutations are common. BKM120 is an oral pan-class I PI3KCA inhibitor. The aim of this study was to evaluate neoadjuvant treatment with BKM120 in PI3KCA mutated early breast cancer in order to assess the effect in PI3K/Akt/mTOR signalling pathway.
Methods: Patients (pts) with previously untreated invasive, non-metastatic histologically confirmed breast cancer, with a tumor size ≥ 1,5cm and non-urgent surgical treatment were enrolled. Only women with ER+ / HER2- and PI3KCA gene mutated were eligible. Patients received treatment with BKM120 (100mg/day; administered orally) during 4 weeks. Subsequently, surgery was performed. Inmunohistochemical analysis of pAkt and pS6 (the H-score intensity x%) as well as KRAS mutation were evaluated on tumor tissue at surgery. H score &lt; 150 was related with inactivation of PI3K signalling pathway.
Results: To date 24 patients has been included in the study (median age, 52,5 years; range 38-69 years;). 13 out of 24 (54%) had PI3KCA mutated and 8 have completed BKM120 treatment. PI3KCA mutation: Exon 20, 4 pts; exon 9, 2 pts; exon 4, 1 pts and exon 20 and 9, 1 pts. One patient discontinued treatment due to adverse event (nausea grade 2). The most relevant adverse events included transitory increase of transaminases. No serious or grade 4 adverse events were observed. Preliminary results of 7 pts showed inactivation of pAkt (H score &lt; 150) in 2 pts with no change in the reminder 5 pts (median H score 300).
Conclusion: Our preliminary data shown that four weeks of BKM120 treatment do not inactivate PI3K/Akt/mTOR signalling pathway, measured throughout pAkt in ER+/HER2-/PI3KCA mutated breast cancer pts. However, we cannot draw any conclusion because the small number of pts included so far. KRAS mutation and pS6 analysis will be presented along with updated results.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-15-09.
Abstract P4-16-05: Hsp90 inhibition potentiates chemotherapy effectiveness in triple negative breast cancer: Role of glucocorticoid receptor signaling
Authors: Agyeman A , Jun W , Proia D , Lee N , Skor M , Conzen S 
Published: August 2014

Abstract
Background: Few promising molecular targets exist for chemoresistant triple negative breast cancer (TNBC). Our laboratory has previously demonstrated that a subset of TNBCs express high glucocorticoid receptor (GR) levels. In breast epithelial cells, GR transcriptional activity directly upregulates the expression of several anti-apoptotic target genes including serum/glucocorticoid regulated kinase 1 (SGK1). High GR and/or SGK1 expression are both associated with decreased chemotherapy-induced cell death in TNBC models. A meta-analysis of patients with early-stage TNBC found that high primary tumor GR (NR3C1) expression significantly associates with earlier relapse compared to GR-non expressing TNBC. Inhibiting GR/SGK1 activity is therefore a testable strategy for improving TNBC responsiveness to chemotherapy.
Both GR and SGK1 require Hsp90 for their activity; therefore, Hsp90 inhibition is predicted to disrupt both GR and SGK1 cell survival signaling in TNBC. Employing a second-generation Hsp90 inhibitor, ganetespib (Synta Pharmaceuticals), we determined the effectiveness of Hsp90 inhibition on GR/SGK1 activity and chemotherapy sensitivity using in vitro and in vivo TNBC models.
Hypothesis: Hsp90 inhibition will decrease GR and SGK1 activity in TNBC in association with improved chemotherapy effectiveness.
Results: Using TNBC cell lines treated with ganetespib at clinically relevant concentrations, we found that total GR and the relative proportion of phosphorylated Ser211 GR were significantly reduced beginning 2 hours following treatment. Reduced glucocorticoid-induced (SGK1) mRNA expression was also seen when cells were pre-treated with ganetespib. We next used fluorescent microscopy and live cell imaging to measure TNBC cell death over a 96 hour time course following chemotherapy +/- ganetespib therapy. Addition of ganetespib to paclitaxel treatment of MDA-MB-231 cells led to significant in vitro cytotoxic synergy; as hypothesized, this synergy was diminished in GR-depleted MDA-MB-231 cells. Cytotoxic synergy following ganetespib and chemotherapy treatment was also seen in vivo in MDA-MB-231 xenografts. Interestingly, tumor GR expression following Hsp90 inhibitor and paclitaxel treatment was significantly reduced compared to tumors from mice treated with paclitaxel alone. Using GR-depleted or control MDA-MB-231 xenografts, studies are currently underway to further characterize the role of GR/SGK1 activity as a target of Hsp90 inhibition to reverse TNBC chemoresistance.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-16-05.
Abstract P5-02-02: Specific gene delivery to Her-2+ breast cancer cells using immunoliposomes
Authors: Kullberg M , McCarthy R , Anchordoquy TJ 
Published: August 2014

Abstract
The objective of our research is to develop a liposomal gene delivery system that specifically targets potent therapeutic genes to breast cancers which are positive for the human epidermal growth receptor 2 (Her-2). Current liposomal gene delivery systems predominately utilize cationic lipids, which efficiently bind and deliver plasmid DNA, but also result in nonspecific gene expression in the lungs and liver tissue. We attempt to improve on specificity, by using a two-component delivery system. The first component is a cationic polyethylene glycol (PEG) grafted polylysine which carries the plasmid DNA. The polylysine/DNA particle binds nonspecifically to cells but has limited ability to bypass the endosomal membrane. The second component is an anionic Her-2 targeting liposome which is disulfide bound to the pore forming protein Listeriolysin O (LLO). These liposomes bind with high selectivity to Her-2 positive cells and once internalized into the reducing conditions of an endosome, release LLO which forms pores in the endosomal membrane. Neither component delivers DNA plasmid on its own, but if the polylysine/DNA and LLO/liposome co-localize within an endosome, the DNA is able to access the cytoplasm which leads to gene expression of the plasmid.
Using fluorescent microscopy and a cell panel, we show that labeled polylysine/DNA and LLO/liposomes have a much greater chance of co-localizing in an endosome of Her-2 positive breast cancer cells compared to Her-2 negative cells. In addition, utilizing luciferase plasmid, we demonstrate that this two-component system results in gene expression that is over 1000-fold greater in Her-2 overexpressing cells than in Her-2 negative cells. This is a vast improvement over standard cationic liposome techniques which show no specificity for Her-2 positive cells.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-02-02.
Abstract P5-03-03: Effect of rapamycin on the function and transformation of aged murine mammary stem cells
Authors: Dong Q , Gao H , Wang D , Bandyopadhyay A , Wu A , Huang C , Sun L-Z 
Published: August 2014

Abstract
Age is the number one risk fact for breast cancer with only 5% of all breast cancers occurring in women under 40 years old and age specific incidence of invasive breast cancer increases from less than 1.5% at age 40, to about 3% at age 50 and over 4% by age 70 in American women. Recent research implicated that adult mammary stem cells (MaSCs) might be responsible for the initiation and progression of certain types of breast cancer. Our preliminary study showed that aging is associated with a significant increase of MaSC frequency, but with a functional decline of self-renewal and differentiation as well as increased neoplastic transformation potential. These findings indicate that aged MaSCs might be the precursors of preneoplastic lesions and serve as the cell of origin for malignant transformation in breast tissue. Therefore, intervention of MaSC aging process could be an effective method for cancer prevention. The drug of rapamycin has been shown to extend life span and ameliorate age-related pathologies (e.g., cancer) in murine models, and a recent study suggested that rapamycin's anti-aging effect may partially act through enhancing the function of tissue-specific stem cells. It is unknown whether rapamycin treatment will also enhance the function of aged MaSCs and decrease their transformation potential. In this study, we fed C57BL/6 mice with microencapsulated rapamycin-containing food (14 mg/kg, food designed to deliver ∼2.24 mg of rapamycin per kg body weight/day to achieve about 4 ng/ml of rapamycin per kg body weight/day) or control diet with empty capsules for 2 year (starting at 2-month old) or 5-10 days (starting at 25.5-month old) and then isolated primary mammary cells at 26-month old for MaSC quantification using an in vitro mammosphere formation and 3D-ECM sphere differentiation assay as well as by the in vivo cleared mammary fat pad transplantation assay. Our findings indicate that short-term (5-10 days) or long-term (&gt; 2 year) rapamycin treatment reversed phenotypic changes associated with aged MaSC, which was mainly characterized by decreased luminal-to-basal cell ratio and increased MaSC frequency. Histological analysis of regenerated glands of aged MaSCs derived from control and rapamycin-treated mice showed a significant decrease of early neoplastic transformation potential in rapamycin-treated group. Subsequent in vivo serial transplantation and mating experiments revealed that rapamycin treatment reverted aged MaSCs more resemble to young MaSCs in self-renewal/differentiation function during regeneration and improved lobulo-alveolar differentiation function for lactation. In conclusion, our findings suggest that rapamycin can rejuvenate the function of aged MaSCs as well as reduce their incidence of preneoplastic transformation.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-03-03.
Abstract P5-04-15: Investigating the role of the AMPK signaling cascade in breast cancer tumor dormancy
Authors: Sullivan KL , Phoenix KN , Fox MM , Kopsiaftis S , Claffey KP 
Published: August 2014

Abstract
Breast cancer can recur in patients long after treatment for initial disease. The mechanisms underlying recurrence as well as the characteristics of these dormant tumor cells remain poorly understood. AMPK (AMP-activated protein kinase) is the central metabolic regulator of the cell, and has two catalytic isoforms, a1 and α2. The loss of AMPK, more specifically AMPKα2, is observed in primary breast cancer and its expression could function to limit tumor expansion in vivo. We hypothesize that the expression of AMPKα2 will confer a survival advantage in dormant breast cancer cells by upregulating the p38MAPK signaling axis. In order to investigate breast cancer dormancy mechanisms in vitro, we generated mammospheres using the estrogen-dependent MCF-7 human breast cancer cell line, which has low expression of AMPKα2. Control MCF-7 cells expressing GFP and MCF-7 cells overexpressing the AMPKα1 or AMPKα2 isoforms were cultured as mammospheres and exposed to various metabolic stressors including estrogen, glucose, and serum deprivation. Spheroids were evaluated for size, viability, gene expression at the RNA level by qRT-PCR, and intracellular signaling by immunoblot as well as immunohistochemistry. AMPKα2 expressing mammospheres were larger and more viable than either the GFP or AMPKα1 expressing spheres. In addition, these cells were resistant to serum deprivation, and upregulated members of the p38MAPK signaling axis, a key player in tumor dormancy. To evaluate estrogen deprivation-induced dormancy in vivo, MCF-7 cell lines expressing either GFP or AMPKα2 embedded in a matrigel matrix were implanted in athymic nude mice containing supplemental slow-release estradiol pellets. After one week, estradiol pellets were removed to induce a dormant period for roughly thirty days. Evaluation of matrigel plugs at this time indicated that AMPKα2 expressing cells demonstrated significant survival whereas GFP expressing cells were significantly depleted. Estadiol pellets were then re-implanted for five weeks to determine if the AMPKα2 expressing cells still responded to estradiol supplementation.This resulted in the AMPKα2 expressing tumors rapidly expanding to a maximal size as compared to the GFP expressing tumors. Consistent with our findings in vitro using mammosphere cultures, the AMPKα2 expressing cells had higher levels of phospho-p38MAPK than the GFP expressing cells, as seen by immunofluorescence. We conclude that the expression of AMPKα2 promotes both survival and dormancy in estrogen-sensitive breast tumor cells, thus implying a significant role in breast cancer recurrence.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-04-15.
Abstract P5-05-06: Menopausal status: An important consideration in determining the biology and prognosis of estrogen receptor-positive and progesterone receptor-negative breast cancer
Authors: Fujisue M , Nishimura R , Nakano M , Tashima R , Nishiyama Y , Osako T , Toyozumi Y , Arima N 
Published: August 2014

Abstract
Background: Transcription of the progesterone receptor (PgR) gene is regulated by estrogen in the breast tissue. PgR loss is considered to be a result in the reduction of estrogen receptor (ER) activity, due to either low circulating estrogen in some older women or a high growth factor signaling. Among the ER-positive breast cancer patients, PR-negative cases frequently have a higher resistance to endocrine therapy, and have a poorer prognosis. Therefore, we examined the clinical significance of ER+/PgR- tumors in luminal/HER2 negative breast cancer and its relationship to menopausal status.
Methods: The sample for this study came from 1791 consecutive patients with HER2 negative primary breast cancer from January 2002 to March 2013. The ER and PgR expressions were evaluated using immunohistochemistry (IHC). 1586cases had ER+/PgR+ tumor, 205cases had ER+/PgR- tumor. The items examined were nuclear grade, Ki-67 index value, TP53, tumor size and number of lymph node involvement. The Ki-67 index value and TP53 were evaluated using IHC and the cut-off values were 20% and 50%, respectively. Recurrence free survival (RFS) and breast cancer-specific survival (BCSS) was calculated using the Kaplan-Meier method and evaluated by the log-rank test or generalized Wicoxon test in stage 1 and 2 breast cancer.
Results: In terms of the distribution of ER and PgR status, ER+/PgR- were frequently seen in postmenopausal patients (13.7% vs 6.8%, respectively). Patients with ER+/PgR-and HER2 negative tumors had significantly smaller tumors, lower Ki-67 values, and a lower nuclear grade in the postmenopausal group compared with those in the premenopausal group. Moreover, RFS trended to be better in the postmenopausal group (p = 0.06), but there was no significant difference. BCSS was significantly higher in the postmenopausal cases (p = 0.001). On the other hand, in patients with ER+/PgR+ tumors, there was no significant difference in RFS and BCSS between the post- and pre-menopausal groups.
Conclusion: The ER+/PgR- tumors were more commonly seen in postmenopausal patients. The biological characteristics of ER+/PgR- tumors were significantly different in terms of the Ki-67 index value, nuclear grade, and the prognosis (BCSS and RFS) between pre- and postmenopausal status. Moreover, the postmenopausal group had a more favorable biology and prognosis than the premenopausal group. Therefore, the findings in this study indicate that menopausal status is related to the biology and prognosis in patients with ER+/PgR- tumors.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-05-06.
Abstract P5-08-13: Alteration of sensitivity to chemotherapeutic agents in tamoxifen resistant estrogen receptor positive breast cancer
Authors: Watanabe T , Okada T , Oba T , Iesato A , Hanamura T , Kanai T , Maeno K , Ito K-I 
Published: August 2014

Abstract
Background: In the treatment of estrogen receptor (ER) positive recurrent breast cancer, sequential treatment with endocrine or chemotherapy is generally used. However, there is no indicator by which we can select the appropriate chemotherapeutic agent to the endocrine resistant breast cancer in the subsequent treatment. The purpose of this study is to examine whether a preceding endocrine therapy affects the sensitivity to subsequent chemotherapy in ER positive breast cancer cells.
Materials and methods: Three ER positive breast cancer cell lines (T47D, MCF7, BT474) and their tamoxifen (TAM) resistant derivatives (T47D/T, MCF7/T, BT474/T) were established and analyzed for sensitivity to doxorubicin (DOX), 5FU and paclitaxel (PTX). The mRNA levels of factors related to drug sensitivity were analyzed by RT-PCR.
Results: MCF7/T became more sensitive to DOX and 5FU compared with the parental MCF7. In addition, the apoptosis induced by 5FU was significantly increased in MCF7/T compared with the parental MCF7. On the other hand, no difference of sensitivity to chemotherapeutic agents was observed in T47D/T and BT474/T compared with their parental cell lines. In MCF7/T and T47D/T, the expressions of dihydropyrimidine dehydrogenase (DPD) were significantly decreased compared with those in the parental cell lines, while no difference was observed in the expression of thymidine synthase (TS). The expression of thymidine phosphorylase (TP) was decreased in MCF7/T.
Conclusion: Our data demonstrate that the sensitivity to 5FU might be altered in a subset of ER positive breast cancer cells, and suggest a possibility that the sensitivity to the chemotherapeutic agents might be modified by the preceding endocrine therapy in ER positive breast cancer cells. We are analyzing drug sensitivity in tumor-bearing mouse model and the data are going to be presented in the meeting.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-08-13.