bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of zoledronic acid on disseminated tumor cells (DTC) in primary breast cancer patients.
Authors: Solomayer E , Gebauer G , Hirnle P , Janni W , Lück H , Becker S , Huober J , Kraemer B , Wackwitz B , Fehm T
Published: December 2010

Abstract #2048

Background: The presence of disseminated tumor cells (DTC) in the bone marrow is associated with an increased risk for subsequent bone metastases. Bisphosphonates reduce the occurence of bone metastases in patients (pts) with primary breast cancer (BC) with DTC. The aim of this trial was to evaluate the effect of adjuvant zoledronic acid (ZOL) on DTC in the bone marrow and the Patients and methods: Eligibilty criteria for this prospective, randomized multicenter trial were primary BC pts (pT1-4, N1-2, M0) with positive bone marrow status as determined by a standardized immunocytochemistry staining procedure. Ninety-eight pts were enrolled between April 2002 and January 2006. Randomization and medication had to be started within 28 days of primary surgery. Consenting pts were randomized to the treatment arm (ZOL 4mg i.v. q 4 weekly) or control arm. During the study, all pts received adjuvant treatment in the form of chemotherapy ± hormonal therapy or hormonal therapy alone. Bone marrow aspirations were performed to analyze the presence of DTC at surgery (baseline) and 12 months later. Efficacy and tolerability of intravenous ZOL in pts with primary Result: Bone marrow status was available for 76 patients both at baseline and 12 months after surgery. At baseline a median of 2.0 / range 1-6 (mean 2.1±1.1) DTC were detected in the ZOL group and a median of 2.0 / range 1-35 (mean 2.9±5.5) DTC in the control group. In both groups the number of detected tumor cells decreased during the 12 months follow-up with 0.5±0.8 (median 0.0; 0-2) DTC in the ZOL group and 0.9±0.8 (median 1.0; 0-2) DTC in the control group. By ANCOVA analysis a trend was seen towards a reduction of the number of DTC in the ZOL group compared with the control group (p=0.066). In addition, bone marrow-positive pts treated with ZOL were more likely to become bone marrow negative after 12 months (66.7% versus 35.1%, (p=0.009) compared to the control group. Most frequently reported AEs were musculoskeletal,arthralgia and myalgia in Conclusions: In this first prospective, randomized, multicenter trial we were able to show, that both treatment groups have a reduction in the number of DTC after 12 months as compared to baseline. There is a tendency to more reduction of DTC in the ZOL group. More pts under ZOL achieved a change from positive to negative bone marrow status than controls (p=0.009). Treatment with ZOL was safe and well tolerated.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2048.
Identification of breast cancer metastasis initiation and virulence genes.
Authors: Ellsworth RE , Heckman C , Love B , Shriver CD
Published: December 2010

Abstract #2049

Background: Metastasis involves processes such as invasion, angiogenesis, intravasation, extravasation and eventual proliferation in the target organ. Metastasis initiation genes are those involved in dissemination of cells from the primary tumor while metastasis virulence genes contribute to metastatic colonization, specifically at the secondary site. Identification of metastasis initiation and virulence genes is critical to improve our understanding of and the ability to effectively treat metastatic breast cancer.  Methods: A 51-gene signature was previously identified using RNA from 20 primary breast and matched metastatic lymph node tumors using the U133 2.0 microarrays (Affymetrix). Real-time PCR was performed for each assay using TaqMan assays (Applied Biosystems) using RNA from 25 pairs of primary breast and matched metastatic lymph node tumors. Data was evaluated using Mann-Whitney testing.  Results: Gene expression levels were significantly different for 40 genes including 25 with P<0.001 and 15 with P<0.05. Thirteen of these genes had significantly higher levels and 27 had lower levels of expression in metastatic tumors. Ten genes had >50-fold difference in expression including WNT2, KRT14, TAC1, COL11A1, MMP13, GRP, and KERA with higher expression in primary tumors and EPHA3, PAX5 and NTS with higher expression in the metastasis.  Discussion: A breast cancer metastasis signature involving 40 genes has been identified and validated. Genes expressed at higher levels in primary breast tumors are largely involved in degradation of the extracellular matrix (ECM), likely enabling cells with metastatic potential to disseminate. Decreased expression of these genes in the metastatic tumors suggests that once tumor cells have disseminated, invasion into foreign tissues does not require active tissue remodeling. Rather, cells that have successfully metastasized are characterized by the expression of genes involved in transcription, metabolism and immune response, potentially blocking cellular differentiation and providing cells with proliferation and survival advantages. These data not only improve our understanding of the biological processes involved in successful metastatic but provide new targets to arrest tumor cells dissemination and metastatic colonization.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2049.
Knockdown of Abl interactor 1 expression impairs invadopodia formation, tumor angiogenesis, and markedly slows tumor growth of breast cancer cells.
Authors: Li C , Sun X , Gilmore WC , Cobos E , Tao Y , Dai Z
Published: December 2010

Abstract #2054

Background: Abl interactor 1 (Abi1) is a key regulator of actin polymerization/depolymerization. Previous studies have revealed that Abi1 interacts with Wiskott–Aldrich syndrome protein (Wasp) family proteins, and regulates the nucleation promoting activity of Wasp proteins. In addition to Wasp family proteins, Abi1 also binds to a variety of other signaling molecules, including those involved in the signal transductions of small GTP-binding protein Rac and PI3 kinase. The ability to interact with diverse signaling pathways places Abi1 at a central position in the signaling network that regulates cell motility and proliferation. The involvement of Abi1 in the development of abnormal cytoskeletal functions of cancer cells has recently been reported. It remains unclear, however, how Abi1 exerts its effects in tumor cells and whether it contributes to tumor progression in vivo.  Material and Methods: The short hairpin RNA (shRNA)-mediated gene silencing was used, in conjunction with murine tumor xenograft models, to examine the effects of Abi1 knockdown on cytoskeleton remodeling, cell migration, invasion, as well as tumor growth and angiogenesis of MDA-MB231 breast cancer cells.  Results: We report here a novel function for Abi1 in the regulation of invadopodia formation as well as in the tumor angiogenesis and invasion of breast cancer cells, possibly through the modulation of Src and matrix metalloproteinase 9 (MMP-9) activities. Abi1 co-localizes with invadopodia, the specialized adhesive/invasive structures believed to control the invasion of tumor cells, in MDA-MB231 breast cancer cells. Epigenetic silencing of the Abi1 gene by shRNA in MDA-MB231 cells impaired the formation of invadopodia and decreased the activity of c-Src and MMP-9. The decreased invadopodia formation and MMP-9 activity correlated with a reduction in the ability of these cells to degrade extracellular matrix (ECM). Remarkably, the knockdown of Abi1 expression inhibited tumor invasion and angiogenesis and markedly slowed tumor growth in xenograft mouse models. Taken together, these results indicate that the Abi1 signaling plays a critical role in breast cancer progression and suggest that this pathway may serve as a therapeutic target for the treatment of human breast cancer.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2054.
Alternative suppression strategy for human breast cancer invasion and metastasis: a potential for a new differentiation therapy.
Authors: Sultan AS , Sherif ZA
Published: December 2010

Abstract #2059

Poor prognosis of human breast cancer is associated with a high potential of cancer cells invasion and metastasis. Epithelial-mesenchymal transition (EMT) is a key event in the tumor invasion process. We have recently uncovered novel evidence that signal transducers and activators of transcription 5a (Stat5a) and its Janus tyrosine kinase, (Jak2), suppress invasion and promote human breast cancer cells differentiation through inhibition of epithelial-to-mesenchymal dedifferentiation.  However, the precise mechanism of Jak2/Stat5a role in human breast cancer is still under investigation.  In this study, we have further critically taken advantage of the combination of Jak2/Stat5a genes expression, HDAC inhibitors, and Mistletoe (Viscum album) plant extracts as an alternative way to suppress breast cancer progression by reversing the mesenchymal phenotype, and restoring homotypic adhesion, and in turn induce tumor differentiation in vitro and in vivo. We have expanded our investigation to involve a highly invasive breast cancer cell line, MDA-231, in addition to BT-20 and T-47D human breast cancer cells that display different phenotypic and differentiation patterns ranging from poor to high differentiation. Cells were pretreated with or without different HDAC inhibitors, and/or Mistletoe (Viscum album) plant extracts, and then either mock infected or infected with adenovirus carrying Wild type (Wt-Jak2), Wt-Stat5a, Dominant negative (Dn-Stat5), or a combination of Wt-Jak2 and Wt-Stat5a.  Using three-dimensional (3D) Matrigel model system in vitro, the pretreatment with HDAC inhibitors and/or Mistletoe (Viscum album) plant extracts synergized with co-expression of Wt-Jak2/Stat5a genes to promote epithelial differentiation by reversing the mesenchymal phenotype morphology, inducing homotypic adhesion, and inhibiting cell motility and invasiveness.  We have also established a xenograft tumor model of MDA-231 cells in nude mice for in vivo studies. After 4 week, the growth of MDA-231 tumors that co-expressing Wt-Jak2/Stat5a was inhibited by 47.90% compared to the mock group (t=2.821, P<0.05) and by 52.86% compared to the tumors expressing Dn-Stat5 group (t=2.394, P<0.05). Furthermore, the pretreatment with HDAC inhibitors and/or Mistletoe (Viscum album) plant extracts enhanced significantly the growth inhibition of MDA-231 xenografted tumors expressing Wt-Jak2/Stat5a compared to the tumors expressing Wt-Stat5a or Wt-Jak2 alone.  Collectively, the observations support a novel role of Jak2/Stat5a genes as a new tool to restore lost differentiation of human breast cancer through inhibiting EMT that could lead to new therapeutic strategies to reverse cancer progression-related changes and introduce alternative cancer treatments in addition to standard chemotherapy and radiation treatment.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2059.
Anoikis-resistant MDA-MB-231 cells: characteristics and pathway analysis.
Authors: Yu J , Han W , Kim J , Lee J , Ko E , Kim E , Moon H , Noh D
Published: December 2010

Abstract #2062

Background : Apoptosis in response to inappropriate adhesion or lack of adhesion has been termed anoikis. Resistance to anoikis is regarded as a prerequisite for invasion and metastasis in cancer cells. Recently many studies were performed to understand mechanism of anoikis resistance. However, there have been few studies on the role and mechanism of anoikis resistance in cancer cells.  Materials and Methods : Anoikis-resistant MDA-MB-231 cells were induced and selected through culture on polyhydroxyethylmethacrylate (Poly-HEMA) substratum and invasiveness by matrigel invasion assay and drug-resistance to doxorubicin were checked. At the same time, expression of genes were evaluated in anoikis-resistant and adherent MDA-MB-231 cells by cDNA microarray. Pathway analysis on high-expressed genes in anoikis-resistant cells was performed by software(Ingenuity Pathway Analysis)  Results : Invasion assays revealed that anoikis-resistant cells were more invasive than adherent cells. Anoikis-resistant cells were also more resistant to doxorubicin than adherent cells. Genes related to NF-kB pathway were highly expressed in anoikis-resistant cells. Therefore, the effect of Bay11-7085, inhibitor of NF-kB, on the growth of anoikis-resistant MDA-MB-231 cells was tested. The blockage of NF-kB pathway inhibited the growth of anoikis-resistant MDA-MB-231 cells.  Conclusion : These results demonstrated that anoikis resistance was associated with increased invasiveness and resistance to chemotherapeutic agents and that NF-kB pathway involved in anoikis resistance.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2062.
Role of Src family members in breast cancer-dependent on site of phosphorylation.
Authors: Elsberger B , Tovey SM , Tan BA , Brown SB , Brunton VG , Mallon EA , Cooke TG , Edwards J
Published: December 2010

Abstract #2074

Background: In vitro work implicates c-Src in breast cancer. However there is little evidence to support this in clinical specimens. Activation of Src family members are associated with phosphorylation at two different tyrosine sites Y419: the classical activation site and Y215, known to induce a 50-fold increase in activation.  We have analysed a cohort of human breast cancers to establish if expression levels of 2 Src family members (c-Src and Lyn) are associated with survival and whether this is dependent on site of activation.  Methods: Tissue microarrays were constructed from 895 breast cancer tumors. Median follow up was 6 years with 229 breast cancer specific deaths. Immunohistochemistry was performed using antibodies to c-Src, Lyn, pSrc419 and pSrc215 (antibodies to Y419 and Y215 will detect phosphorylation of either c-Src and Lyn). Expression was assessed by two independent scorers. All statistical calculations were performed using SPSS 15.  Results: Membrane expression of c-Src and Lyn was rarely observed. However, cytoplasmic expression of c-Src and Lyn was frequently observed and further results presented relate to this site. High expression levels of c-Src but not Lyn were associated with HER2 positivity (p=0.001) and ER negativity (p<0.001).  High c-Src expression was associated with a poor outcome. In direct contrast pSrc215 was associated with improved outcome on univariate and multivariate analysis.  Antibodies to phosphorylation sites will detect both activated c-Src and Lyn (and other family members). The individual impact of phosphorylation on clinical outcome was determined by categorising expression based on overexpression of c-Src or Lyn in combination with activation at each site.    Discussion: Our findings demonstrate that phosphorylation of c-Src at Y419 is associated with poor prognosis in breast cancer. In contrast phosphorylation at Y215 was independently associated with better outcome.  Further work is ongoing to explore our hypothesis that:  1. phosphorylation at 215 'deactivates' c-Src or desensitizes downstream pathways or,  2. that activation of Lyn or other Src family members at 215 is responsible for good outcome.  If confirmed, these results strongly suggest that commercial development of highly specific Src inhibitors is necessary and that these will require appropriate patient selection.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2074.
Analysis of the rate of missing data, the rate of discordance between readers, and the rate of site versus central discordance in clinical studies of recently approved breast cancer agents that have used blinded independent central review.
Authors: Borradaile K , Cadogan K , Somers S , Ford R
Published: December 2010

Abstract #2081

Background: The United States Food and Drug Administration (USFDA) recommends blinded independent central review (BICR) for oncology registration studies when the primary study endpoint is based on tumor measurements, such as progression-free survival (PFS) or objective response rate (ORR). However, there is no published guidance regarding acceptable metrics during the BICR.  Method: The USFDA Summary Basis of Approvals and Oncologic Drugs Advisory Committee (ODAC) transcripts for the following recently approved breast cancer therapies: Gemzar, Abraxane, Tykerb, Ixempra, and Avastin, were reviewed with attention to metrics referable to the BICR. The findings are summarized.  Results: Up to 13% of subjects were reported as unevaluable at the BICR based on missing data, with missing data defined as missing radiographic evaluations. The rates of discordance between two readers during the BICR were reportedly between 34-51% depending on the number of adjudication variables. The rates of discordance between the site and BICR were reportedly between 34-49% for the date of progression and 24-29% for the progression status. Up to 9% of subjects enrolled with measurable disease at baseline did not have this confirmed by the BICR. The causes of discordance were reportedly related to differences in the methodologies used to perform the reviews, and clinical or image data that was missing at the time of the BICR. Additional reported causes included imaging requirements not detailed in the protocol, the BICR charter containing more stringent requirements for determining response and progression than was indicated in the protocol, protocol amendments issued midway through the study which changed the imaging eligibility criteria for the sites while the BICR used the same requirements throughout the study, differences in the choice and classification of lesions, radiographic exams only repeated at subsequent time points if deemed positive by the investigator resulting in missing data and unevaluable assessments at the BICR, variability in measurement of small lesions, and discordance in the determination of new lesions. Inter- and intra-reader variability was reported in a small population of subjects; 8% resulted in 1-step response discrepancies for inter-reader variability and 31% for intra-reader variability.  Conclusion: Based on FDA approvals, metrics as described above may prove to be valuable benchmarks when using BICR data to determine endpoints in future breast cancer studies.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2081.
Admixture mapping to identify breast cancer susceptibility loci in African American women.
Authors: Croft DT , Mao X , Hooke JA , Shriver CD , Shriver MD , Ellsworth RE
Published: December 2010

Abstract #2090

Background: The incidence of breast cancer in young women is higher in African American (AAW) compared to Caucasian (CW) and is associated with an aggressive phenotype, including high-grade, ER/PR and HER2 negative status and p53 positive characteristics. The aggressive tumor behavior and pathological features of AAW are also seen in women from the Bite of Biafra, an area of Western Africa that was the predominant source of the American slave trade. Similar tumor characteristics and shared ancestry suggest that population-specific molecular factors contribute to the aggressive tumor phenotypes associated with AAW. Therefore, a method of admixture mapping is proposed for this study. Admixture mapping is also known as mapping by admixture linkage disequilibrium. It assumes in a recent admixed population, if certain phenotype or the prevalence of a disease is mainly caused by one of the ancestral groups, the genetic variant can be located by the elevated ancestry from that group.  Methods: Pathological characterization was performed histology specimens from 91 self-described AAW diagnosed with invasive breast cancer enrolled in the Clinical Breast Care Project. Genomic DNA was isolated and SNP data generated using the Affymetrix Mapping 100K arrays. African ancestry was determined using maximum likelihood estimator and chromosomal regions associated with disease identified using AncestryMap and AdmixMap.  Results: The average age of diagnosis was 51 years. 25% of patients had poorly-differentiated, triple negative tumors. All 91 patients had significant African ancestry, with a mean level of Nigerian ancestry of 0.3857. Results from both AncestryMap and AdmixMap suggest loci on chromosomal regions 5q32.2, 9q13.1 and 17p13.3 are associated with the development of breast cancer.  Discussion: Recently, admixture mapping was used to successfully identify a prostate cancer gene to chromosome 8q24 in African American men. Using a similar approach, we identified three chromosomal regions associated with the presence of invasive breast cancer in AAW with significant Western African ancestry. Of note, loss of 9q13 has been associated with poor survival, and allelic imbalance of 17p13.3 has been associated with loss of hormone receptor expression and poor prognosis. Thus, the use of admixture mapping may aid in the identification of genes involved in the development of the aggressive form of breast cancer associated with AAW.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2090.
Triple negative status as a risk factor for the development of brain metastases in African American breast cancer patients.
Authors: Khan AM , Sabnani I , Rogers-Phillips E , Tsang P , Voora R , Pinera E , Cohen AJ
Published: December 2010

Abstract #2093

Background: Previous studies have described triple negative (TN) breast cancer (ER/PR/ HER2/neu negative) as an aggressive and poor prognostic phenotype with higher relapse rate (RR), distant RR, and shorter survival. The incidence of TN breast cancer has reportedly been higher (30-35%) in African American (AA) women compared to the general population (15%) but the clinical outcomes of TN patients (pts) who develop brain metastases compared to the non-triple negative (NTN) group has not been well described.  Methods: We retrospectively reviewed tumor registry data from a large academic medical center serving an inner city population. A total of 282 AA women with invasive breast cancer were identified from 1994-2006 and 248 were determined to be in stages I-III. Characteristics evaluated include age, TNM stage at diagnosis, ER, PR, Her2/neu status, and grade. The RR, distant RR, rate of brain metastases, time from diagnosis to brain metastases, and overall survival were determined.  Results: The incidence of TN disease in AA women was 30% (82/282). Median age (57 yrs) was similar in both TN and NTN groups. With a median follow-up of 5.5 years, the RR (30% vs. 14%; p=0.02) and distant RR (22% vs. 10%; p=0.02) were higher for the TN vs. NTN group. Six of 72 (9%) TN pts developed brain metastases compare to 6/178 (3%) in NTN group. There was a shorter time to development of brain metastases (1.7 vs. 6.1; p=0.01) and a lower survival time after brain metastases (0.6 yrs vs. 1.6 yrs) in the TN vs. NTN group.    Conclusion: This study represents one of the largest reported series of AA women with breast cancer. TN pts are at higher risk of developing brain metastases. Not only the time to develop brain metastases was shorter but overall survival after development of brain metastases remained poor in TN group compared to NTN group. TN status should be considered as an independent risk factor for the development of brain metastases.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2093.
Quality of life in relation to hormonal treatment of postmenopausal women in the Dutch Tamoxifen Exemestane Adjuvant Multicentre (TEAM) trial.
Authors: van Nes JG , Voskuil DW , van Leeuwen FE , Junggeburt JM , de Haes HC , van de Velde CJ
Published: December 2010

Abstract #21

Background In the last decade, use of adjuvant hormonal treatment increased as well as its duration. Aromatase inhibitors are associated with a minimal increase of disease free survival compared to tamoxifen. Both therapies are associated with different side effects which can affect quality of life (QoL). Therefore, it is necessary to compare the QoL of patients using these therapies. We compared the QoL of women participating in the Dutch Tamoxifen Exemestane Adjuvant Multicentre (TEAM) Trial.  Patients and Methods The Dutch TEAM trial included 2754 postmenopausal early breast cancer patients who were randomised between five years of exemestane or 2.5-3 years of tamoxifen followed by 2.5-2 years of exemestane. A total of 742 patients were invited onto the QoL subprotocol. At one (T1) and two (T2) years after start of hormonal treatment, patients were ask to fill in questionnaires. This questionnaire contains the European Organisation for Research and Treatment of Cancer (EORTC) QLQ C30 and the EORTC BR23 questionnaires, supplemented with Functional Assessment of Cancer Therapy - Endocrine Subscale (FACT-ES) questions covering endocrine symptoms. The endpoint was the difference in QoL between patients receiving tamoxifen or exemestane.  Results Questionnaires were completed by 543 patients at T1 and 83% of these returned the questionnaire of T2. There were no significant differences in physical functioning, role functioning, cognitive functioning, emotional functioning, body image, breast symptoms, arm symptoms and endocrine symptoms between both treatment groups at T1 nor at T2. Patients receiving exemestane had significantly less sexual enjoyment (difference of 9 points on a 0-100 scale; p=0.004) and more insomnia (difference of 8 points; p=0.005) compared to patients receiving tamoxifen at T1. At T2, there was no statistically significant difference in sexual enjoyment (difference of 4 points; p=0.287). However, patients receiving exemestane reported significantly worse sexual functioning (difference of 5 points; p=0.020) and still more insomnia (difference of 8 points; p=0.004).  Conclusion Patients using exemestane reported less sexual enjoyment and more sexual functional problems than patients using tamoxifen. This may be explained by the fact that specific side effects of exemestane (e.g. vaginal dryness) can cause less sexual enjoyment which can result in a decreased sexual functioning.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 21.
Development and evaluation of a cancer risk educational tool (CREdIT) for women with a family history of breast and ovarian cancer.
Authors: Wilcox C , Lee R , Beattie M , Luce J , Joseph G , Lamvik K , Crawford B , Ziegler J , Braithwaite D
Published: December 2010

Abstract #2101

Introduction: In underserved, lower literacy and multiethnic women at risk of Hereditary Breast and Ovarian Cancer (HBOC), there is a need for culturally appropriate educational tools. The purpose of this Phase I study is to evaluate the use of a Cancer Risk Educational Intervention Tool (CREdIT) as an adjunct to genetic counseling for HBOC for underserved women at San Francisco General Hospital (SFGH).  Methods: CREdIT is a 15 minute audio-visual powerpoint story presentation (available in English and Spanish) which employs non-scientific images and language specifically designed for use by our target population. Participant questionnaires, administered before and after the intervention, evaluate patient satisfaction, risk perception, knowledge of cancer genetics, and anxiety. Genetic counselor questionnaires address counselor satisfaction and time-flow.  Results: To date, we have recruited 23 women of diverse backgrounds (mean age of 46, range: 26 to 63). Of these, seven (30%) are first-generation immigrants and four (17%) have less than a high school diploma. Eight (35%) have had cancer, and eighteen (78%) reported that cancer runs in their families. We have found an increase in knowledge following the CREdIT presentation, specifically vis-à-vis BRCA inheritance, BRCA-associated cancer risk, and risk-reducing options (all p < 0.05). These improvements occur without an increase in patient anxiety (p > 0.05). All participants believed that the presentation helped them learn more about cancer risk, and genetic counselors reported increased patient preparedness and counselor satisfaction as a result of CREdIT use (p < 0.05). Mean genetic counselor consultation time decreased by 5.5 minutes after CREdIT use.  Conclusions: CREdIT appears to increase knowledge and improve understanding of BRCA-associated risks without raising anxiety in underserved women at risk of HBOC. Genetic counselors report increased satisfaction and patient preparedness, and decreased counseling time with CREdIT. Future work will involve examining long-term outcomes of CREdIT use; subgroup analyses to identify patient populations most likely to benefit from CREdIT; further evaluation using clinical trial methodology; and strategies for its dissemination to other settings working with underserved, multiethnic populations.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2101.
A 24-month subgroup analysis of the effect of denosumab on bone mineral density in women with breast cancer undergoing aromatase inhibitor therapy.
Authors: Ellis GK , Bone HG , Chlebowski R , Paul D , Spadafora S , Fan M , Kim D
Published: December 2010

Abstract #2106

Background: Accelerated bone loss and fracture risk are expected consequences of adjuvant aromatase inhibitor (AI) therapy. We previously showed that denosumab, a fully human monoclonal antibody that inhibits RANK ligand (RANKL), significantly increased bone mineral density (BMD) at the lumbar spine and at all measured skeletal sites at 12 months compared with placebo in women with breast cancer undergoing adjuvant AI therapy (Ellis et al, 2007 SABCS). In this analysis, we assessed covariates that may influence treatment effects on BMD at the lumbar spine, total hip, femoral neck, and 1/3 radius at 24 months.  Methods: Adult patients (pts) with hormone receptor-positive breast cancer, who had evidence of low bone mass and were receiving adjuvant AI therapy, were enrolled in this randomized, double-blind, placebo-controlled, phase 3 study. Pts were stratified according to length of previous AI therapy (≤ 6 vs > 6 months) and randomly assigned to receive, together with calcium and vitamin D, placebo (n=125) or denosumab 60 mg (n=127) subcutaneously every 6 months for 4 doses. Subgroup analysis was conducted using analysis of covariance and adjusted for treatment, stratification factor, baseline BMD value, densitometer type, and baseline BMD value-by-densitometer-type interaction.  Results: At 24 months, greater increases in BMD were seen at all measured skeletal sites (both trabecular and cortical bone) for denosumab compared with placebo, regardless of the subgroup (table). Adverse events (AEs) occurred at a similar rate in both groups (91% denosumab, 90% placebo).  Conclusion: In pts with breast cancer undergoing adjuvant AI therapy, twice-yearly denosumab treatment showed consistent increases in BMD across the skeleton at 24 months compared with placebo, regardless of subgroups.   

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2106.
A pilot study of adjuvant doxorubicin and cyclophosphamide followed by paclitaxel plus sorafenib in women with node positive or high-risk breast cancer.
Authors: Spigel DR , Molthrop D , Peacock N , Kommor M , Markus T , Vazquez E , Greco FA , Burris HA , Hainsworth JD , Yardley DA
Published: December 2010

Abstract #2110

Background: Targeting angiogenesis is an effective treatment strategy in many solid tumors including breast cancer (BC). Sorafenib is a small molecule inhibitor of angiogenesis and other tumor growth signaling. We conducted a pilot phase 2 trial incorporating sorafenib into standard adjuvant BC treatment. Material and Methods: The primary endpoint of this multicenter community-based study was to assess the safety of doxorubicin and cyclophosphamide followed by paclitaxel in combination with sorafenib in patients (pts) with node positive or otherwise high-risk BC. Eligibility criteria included: either mastectomy or breast conserving surgery-with axillary node assessment for stage I, II, IIIA, and IIIC (T1-3, N3a only) BC. Pts were either lymph node positive or high-risk node negative (tumor size >2 cm; hormone receptor negative; grade 2-3; or age <35 years). Additional inclusion criteria included: HER2-negative, ECOG performance status 0-1, normal left ventricular ejection fraction by echocardiography or MUGA scan, adequate organ function, and signed informed consent. Treatment consisted of doxorubicin 60mg/m2 and cyclophosphamide 600mg/m2 (AC) both IV day 1 every 3 weeks x 4 cycles, followed by paclitaxel 175mg/m2 day 1 every 3 weeks x 4 cycles or 80mg/m2 IV weekly x 12, combined with sorafenib 400mg orally twice daily. Sorafenib was held during radiation therapy (where indicated) and resumed once completed. Sorafenib was continued for a total of 12 months and in combination with adjuvant hormonal therapy (where indicated.) LV assessments occurred after AC, paclitaxel, and every 3 months during maintenance sorafenib. Results: Forty-five pts were enrolled from 5/07 to 1/08. The median follow-up is 6 months (range 4-12 months). Baseline characteristics included: median age 54 years (35-74); ECOG 0, 93%; node positive, 80%; and hormone receptor negative 33%. Nineteen pts (42%) discontinued sorafenib before completing paclitaxel (mean time on sorafenib 3.7 weeks; <1 week in 18% of all pts). 9 of these 19 pts (47%) stopped sorafenib due to symptoms. Grade (G) 3/4 non-hematologic toxicity during sorafenib therapy in >5%: arthralgias/myalgias, neuropathy, pain, and pulmonary symptoms (8% each), and rash (11%). G3/4 hematologic toxicity during sorafenib treatment was limited to neutropenia in 11%. There were no sorafenib-related deaths. Discussion: In this pilot study, sorafenib was generally associated with limited severe toxicity when combined with paclitaxel following AC. However, many pts discontinued sorafenib early suggesting sequential scheduling may be more feasible than concurrent administration with chemotherapy.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2110.
Preliminary toxicity results of a phase II trial of adjuvant docetaxel/cyclophosphamide plus trastuzumab in HER2+ early stage breast cancer patients.
Authors: Jones SE , Collea RP , Oratz R , Paul D , Sedlacek SM , Holmes FA , Portillo RM , Crockett MW , Asmar L , O'Shaughnessy JA , Robert NJ
Published: December 2010

Abstract #2111

Background: Docetaxel/cyclophosphamide (TC) has demonstrated superior activity to doxorubicin/cyclophosphamide (AC) in the adjuvant treatment of patients (pts) with early breast cancer and is devoid of known cardiac toxicity (Jones et al, SABCS 2007, abstract 12). Although the addition of trastuzumab (H) to anthracycline-based adjuvant regimens has proven effective, it has also been associated with increased cardiac toxicity. Therefore, a short course of the nonanthracycline TC regimen coupled with H appeared to be a logical combination for women with lower risk HER2+ breast cancer. We report safety and tolerability of the TC+H regimen.  Patients and Methods: 256 of a planned 260 patients (pts) were registered to the study and stratified by positive or negative nodes. On Day 1 of each 21-day cycle for a total of 4 cycles, pts received (in order): (T) 75 mg/m2 IV, followed by (C) 600 mg/m2 IV. Weekly (H) was also given at 4 mg/kg IV (loading dose, over 90 minutes Day 1, Cycle 1 only) and 2 mg/kg IV (Days 1, 8, 15) thereafter throughout chemotherapy. After completion of chemotherapy, H was administered at a dose of 6 mg/kg IV every 3 weeks to complete 12 months of therapy with H. Pts must have had LVEF >50% at the time of registration and had regular cardiac evaluation throughout the study (MUGA or ECHO).  Results: To date, 231 pts were treated and comprise the safety population; this first report focused on toxicity occurring during the first 4 months of co-administration of chemotherapy and H. The median age was 55 years; 84% of pts were ECOG 0; 61% were ER+. Selected treatment-related toxicities in ≥3% of pts are listed in Table 1. Of the 231 pts, 10 pts came off treatment due to adverse events: hypersensitivity (3), gastrointestinal (2), hematologic (2), pulmonary (1), skin (1), and cardiac (1). To date, only 1 patient has had a significant drop in LVEF to 40%, and was taken off treatment.    Conclusion: 4 cycles of TC combined with H is a well-tolerated adjuvant treatment with an acceptable toxicity profile for lower risk patients with HER2+ breast cancer.  This research was supported, in part, by a research grant from sanofi-aventis, Bridgewater, NJ.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2111.
The number needed to treat (NNT) as a measure of drug efficacy: the case of zoledronic acid for early hormone-responsive breast cancer in the ABCSG-12 trial.
Authors: Gnant M , Mlineritsch B , Schippinger W , Luschin-Ebengreuth G , Steger G , Bjelic-Radisic V , Jakesz R , Kubista E , Marth C , Greil R ,   on Behalf of the Austrian Breast and Colorectal Cancer Study Group
Published: December 2010

Abstract #2113

Background: Zoledronic acid (ZOL) has demonstrated antitumor and antimetastatic activities in preclinical and early clinical studies in many cancer types. The Austrian Breast and Colorectal Cancer Study Group Trial 12 (ABCSG-12) examined the efficacy of adjuvant therapy in premenopausal women with hormone-responsive early breast cancer receiving goserelin (GOS) + anastrozole (ANA) or tamoxifen (TAM), both ± ZOL. In this trial, ZOL significantly prolonged disease-free survival (DFS) and recurrence-free survival (RFS) versus no ZOL. However, in addition to relative risk reduction, the potential for patients to benefit from a treatment is an important consideration. The number needed to treat (NNT) represents an estimation of the number of patients that have to be treated with an investigational drug for 1 patient to receive clinical benefit within a specific follow-up period. NNT is a powerful, clinically relevant measure of efficacy that can provide a real-world perspective on the efficacy results from clinical trials. Methods: 1,803 patients were randomized to GOS (3.6 mg/28 d SC) + TAM (20 mg/d PO) ± ZOL (4 mg/ 6 mos IV) or GOS + ANA (1 mg/d PO) ± ZOL for 3y. Endpoints at 60 mos for TAM vs ANA and ZOL vs no ZOL were DFS (primary), RFS, overall survival and safety. NNT was calculated for ZOL with respect to DFS and RFS, and compared with other paradigm-changing cancer therapies. Results: After 60 mos median follow-up, ZOL significantly reduced the risk of DFS events by 36% (P = .01) and RFS events by 35% (P = .02) vs no ZOL. For ZOL therapy, NNT = 31 and NNT = 33 to prevent 1 DFS or 1 RFS event respectively at a median follow-up of 60 months. In comparison, the NNT with respect to DFS is 28 for paclitaxel (60-69 months follow-up) and 31 for docetaxel (43-60 months follow-up). Moreover, ZOL was generally well tolerated, and neither ONJ nor renal toxicity was an issue in this setting. Conclusions: The NNT is a simple and effective method to assess clinical trial results that will have relevance to daily practice. In the current comparisons, the NNT for ZOL plus endocrine therapy in ABCSG-12 was similar to the NNTs for taxanes. Therefore the addition of ZOL provides DFS and RFS benefits of magnitudes similar to those from practice-changing chemotherapies like taxanes.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2113.
Ligand-mediated selective targeting of adenovirus in metastatic breast cancer.
Authors: Stoff-Khalili MA , Bhatia S , Odaka Y , Li XL , Podduturi J , Smart L , Mallmann P , Schmutzler RK , Curiel DT , Mathis MJ
Published: December 2010

Abstract #2126

The success of gene therapy relies on efficient and targeted delivery systems. Adenovirus vectors have a number of advantages for gene therapy. However, because of their lack of tumor tropism and their tendency to induce liver infection following systemic administration, they cannot be used for systemic attack on metastatic disease. Many solid tumors (e.g., colon, lung, and breast) and hematopoietic tumors over express the chemokine receptor CXCR4. CXCR4 belongs to the large superfamily of G protein-coupled receptors, and is known to participate in a number of biological processes including organogenesis, hematopoiesis, and immune response. Recent evidence has highlighted the role of CXCR4 in cancer, particularly in cancer metastasis due to dysregulation of the receptor leading to enhanced signaling. The present study addresses this issue by retargeting adenovirus to the breast cancer cells overexpressing CXCR4 receptor. We used sCAR-T4-CXCL12, a bispecific adaptor molecule with the ectodomain of CAR linked by the T4 fibritin trimerization motif to the human CXCR4 ligand CXCL12 (also known as SDF-1). The sCAR-T4-CXCL12 should therefore be useful in retargeting adenovirus vectors to CXCR4-positive metastases. Infectivity assays in the absence as well as presence of ligand were performed in human breast cancer MDA-MB-435 cells. Cells were infected with different titres of Ad-CMV-GFP-Luc with and without ligand. Forty-eight hours post-infection, cells were harvested and analysed for the GFP expression by fluorescent microscopy and flow cytometry. It was further interesting to observe the time-dependence of infectivity curve. For this purpose, MDA-MB-435 cells were incubated with optimum titre of Ad-CMV-GFP-Luc vector in the presence of CXCR4 targeting ligand at different time intervals. This was followed by expression analysis of GFP protein by fluorescent microscopy and flow cytometry. Quantification by flow cytometry demonstrated a dramatic 20- to 40-fold increase in the infectivity of MDA-MB-435 cells both in a dose-dependent and time-dependent manner using the sCAR-T4-CXCL12 targeted adenovirus compared to the untargeted vector. In this report, we show that sCAR-T4-CXCL12 can significantly redirect an adenoviral gene therapy vector to CXCR4-positive breast cancer cells in culture. This bispecific ligand should, therefore, be a powerful agent to retarget adenovirus vectors to tumor metastases. The future goal is to investigate the capacity of this agent to re-direct adenoviral vectors in vivo using breast cancer metastasis models.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2126.
Effective tumor growth inhibition of MX1 and MDA-MB-231 estrogen receptor negative human breast cancer xenografts by treatment with LHRH antagonist cetrorelix.
Authors: Seitz S , Schally AV , Papadia A , Glueck S , Calfa C , Ortmann O , Buchholz S
Published: December 2010

Abstract #2137

Introduction  Agonists of LHRH are a treatment option in premenopausal women with estrogen receptor positive breast cancer. The treatment with those agonists decreases the levels of FSH and LH in the blood and thus reduces the levels of sex hormones. Patients with estrogen receptor negative breast cancers do not benefit from therapy with LHRH agonists. Antagonists of LHRH lower LH, FSH and sex steroid levels but without the initial flare up of FSH and LH. In addition to the endocrine effects, Cetrorelix also shows a direct inhibition of cell growth in LHRH receptor (LHRH-R) positive gynecological cancer in vitro where alterations of FSH, LH and sex hormone levels are clearly excluded. In view of these findings we decided to investigate Cetrorelix on the tumor growth in two estrogen receptor negative but LHRH-R positive breast cancer cell lines.  Materials and Methods  The mRNA expression of LHRH-R was detected by PCR. For proliferation assays cells were treated with increasing doses of Cetrorelix acetate in 0.5% FBS supplemented RPMI 1640 media. MTS assays were performed after 72h. Fluorescence microscopy using ethidium bromide staining was performed to show cell death. In the in vivo study, nude mice were treated with Cetrorelix pamoate preparation at a dose of 3mg s.c. releasing an estimated 100mg Cetrorelix/day.  Results  MX1 and MDA-MB-231 estrogen receptor negative human breast cancer cell lines were positive for the expression of mRNA for LHRH-R. The cell proliferation in vitro of MX1 and MDA-MB-231 lines treated with different concentrations of Cetrorelix was significantly inhibited in a dose dependent manner. Time and dose dependent cell death was observed by fluorescence staining. Experimental treatment in vivo with Cetrorelix pamoate preparation reduced a significant inhibition of tumor growth in MX1 xenografts as compared to the Controls after 14 days and the suppression remained significant until the end of the study on day 28. MDA-MB-231 xenografts treated with Cetrorelix also showed a significant inhibition of tumor growth compared to the Control as early as day 7 and the inhibition remained significant until the end of the study on day 28.  Conclusion  Our results indicate a direct inhibitory effect of Cetrorelix on LHRH-R positive breast cancers. Since LHRH-R are expressed in ER negative breast cancers, these findings suggest a new approach to the treatment of LHRH-R positive breast cancer patients independent of the estrogen receptor status.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2137.
Drug efflux by breast cancer resistance protein (BCRP) is a mechanism of resistance to the insulin-like growth factor receptor/insulin receptor inhibitor, BMS-536924.
Authors: Haluska P , Carboni JM , Asmann YW , Ten Eyck C , Attar RM , Tibodeau JD , Hou X , Nakanishi T , Ross DD , Kaufmann SH , Gottardis MM , Erlichman C
Published: December 2010

Abstract #2149

Background: Inhibitors of the insulin-like growth factor 1 receptor (IGF-1R) are currently undergoing clinical testing. Preclinical investigations have identified IGF-1 signaling as a key mechanism for breast cancer growth and resistance to clinically useful therapies, including tamoxifen and trastuzumab. Thus, agents targeting IGF-1R have promise in the treatment of breast cancer. Determining mechanisms that can confer resistance to these agents may aid their clinical development.  Methods: To understand factors may be important in predicting sensitivity to targeting the IGF-1 signaling pathway, we developed a cell line (MCF-7R4) that is resistant to BMS-554417, a small molecule, dual-kinase inhibitor of IGF-1R and insulin receptor (InsR). Compared with the parental MCF-7 cells, MCF-7R4 cells are 40- to 50-fold resistant to BMS-554417 and cross-resistant to the similar compound BMS-536924. The expression profiles of MCF-7R4 and that of MCF-7 were compared using Affymetrix GeneChip Human Genome U133 Plus 2.0 Arrays. Intracellular concentrations of BMS-536924 were examined by reverse phase high performance liquid chromatography. BMS-536924 cellular accumulation in vitro was visualized by fluorescence microscopy using a DAPI filter set. MCF-7 cells stably transfected with either the empty mammalian expression vector pcDNA (MCF-EV) or full length BCRP (MCF-BCRP) were examined for sensitivity to BMS 536924 by MTS assays.  Results: Compared to MCF-7 cells, BCRP expression was increased 9-fold in MCF-7R4, which was highly statistically significant by t-test (p= 7.13E-09). Little change was observed in other ABC transporter proteins, including ABCB1. No change was observed in IGF-1R or InsR expression. BCRP overexpression in MCF-7R4 cells was confirmed by western blotting. MCF-7R4 cells had significantly lower intracellular accumulation of BMS-536924 compared to MCF-7 cells. Confirming these results, MCF-BCRP cells were significantly less sensitive to the cytoxic effects of BMS-536924 cells than MCF-EV cells.  Conclusions: BCRP expression was stimulated by prolonged exposure of MCF-7 cells to BMS-554417. Upregulation of BCRP is one of the most significant changes observed in MCF-7R4 cells in comparison to parental cells. BCRP expression decreased cellular exposure to BMS-536924 and was sufficient to confer resistance. These data suggest that BSM-536924 is a substrate for BCRP-mediated efflux. Expression of BCRP may be important in de novo and acquired resistance to benzimidazole –based inhibitors of IGF-1R/InsR. Supported in part by the Mayo Clinic Breast SPORE (CA116201-03), NIH K12 (CA090628-05) and the Mayo Clinic Cancer Center (CA15083).

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2149.