bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract P2-19-05: Oncoplastic breast conserving surgery with perforator flap in breast cancer patients
Authors: Park HY , Kang JG , Choi HH , Hwang SO , Kim WW , Jung JH , Lee YH , Yang JD , Lee SJ 
Published: August 2014

Abstract
Purpose : Oncoplastic breast surgery has been used widely as a treatment protocol for breast cancer. Thoracodorsal artery perforator (TDAP) flap and intercostal artery perforator (ICAP) flap can provide adequate cover without sacrificing any muscle and allow closing of the donor sites in inconspicuous sites. Therefore, among the oncoplastic volume replacement techniques indicated using local flap that can adequately cover the volume of breast, TDAP and ICAP are especially suggested. This study describes the use of TDAP and ICAP flap techniques after breast conserving surgery. Methods : From March 2010 to August 2012, 38 patients with breast cancer received breast reconstruction. All patients who were selected had small- to moderate-sized defects on breasts, middle aged, and were not sensitive to scars. The TDAP flap is the first choice for performing the surgery, but if the perforator of the TDAP flap is not found, a dissection toward the anterior area to find an adequate perforator is made and the serratus anterior artery perforator is normally used. Otherwise after the dissection is performed more anterior, ICAP can be used. If the perforator penetrates the LD muscle, the TDAP flap can be used. The perforator that penetrates from the serratus anterior muscle is also used in the anterior area. Otherwise, ICAP can be used in partial breast reconstruction. The TDAP flap can be applied to any defect site regardless of the size of the defect area. Results : The mean age was 44.9 years and the average follow-up interval was 6 months. The average specimen weight was 98g. Complications developed in 4 cases including 3 cases of venous congestion, though self-limited, and 1 case of wound disruption on the inframammary fold suture area. Majority of the patients were satisfied with the cosmetic result.
Conclusion : Thoracodorsal artery perforator flap (TDAP) and intercostal artery perforator flap (ICAP) techniques can be reliable and useful in correcting breast deformity after breast conservation surgery, especially in patients with small- to moderate-sized defects on breasts.
Key Words : intercostal artery perforator flap, thoracodorsal artery perforator flap Oncoplastic surgery, ICAP, TDAP.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-19-05.
Abstract P3-01-01: Targeting glutamine metabolism in breast cancer for therapy
Authors: Korangath P , Sadik H , Mori N , Wildes F , Zhang Z , Bhujwalla Z , Sukumar S 
Published: August 2014

Abstract
Metabolic reprogramming of cancer cells is observed in different types of tumors including breast. Oncogenic signals aid changes in metabolism that provide selective advantage to the cancer cells to meet their energy requirements to accomplish rapid proliferation. The increased dependence on the glycolytic pathway for energy called the “Warburg effect” was reported by Otto Warburg several decades ago. Our recent understanding of cancer metabolism has thrown light on alternative energy sources, especially glutamine and other branched chain amino acids. The role of glutamine in breast cancer cell growth has not yet been studied extensively.
In this study we found that a number of breast cancer cell lines, especially those negative for ER, PR, HER2, display a high dependence on glutamine for their survival and growth. Interestingly, most of these glutamine-dependent cell lines express high levels of c-myc protein. Consistent with their growth dependency on glutamine, transaminases responsible for entry of glutamine into the tricarboxylic acid cycle are transcriptionally up regulated under low glutamine conditions. Consequently, growth of these cancer cell lines was found to be specifically inhibited by the transaminase inhibitor, amino oxyacetate (AOA). Moreover, the AOA mediated cytotoxic effect was partially c-myc dependent. Through 1H-NMR studies of AOA-treated cells we show that in addition to glutamine, AOA treatment decreases the aspartate and alanine content in the cells. In line with these findings, exogenous supplementation with aspartate partially rescued the cells from the growth inhibitory effects of AOA. Flow cytometry analysis showed that AOA causes cell cycle arrest in the S phase. AOA also had significant inhibitory effect on in vivo growth of rapidly growing SUM 149 and SUM159 xenografts in immunodeficient mice. When combined with chemotherapeutic agents, doxorubicin and carboplatin, AOA inhibited growth of MDA-MB-231 xenograft tumors more effectively than AOA alone. Lastly we present evidence that the cytotoxic effect of AOA is mediated through activation of the ER stress pathway, combined with depletion of key amino acids and likely, a reduction in the nucleoside pool in the cells. Our preclinical studies, both in vitro and in vivo, combined with development of intermediate markers of response, provide a strong rationale for testing AOA for therapy in Phase 0 clinical trials.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-01-01.
Abstract P3-02-01: Pregnancy-associated plasma protein A regulates mitosis and is epigenetically silenced in breast cancer
Authors: Sainsbury R , Loddo M , Andryszkiewicz J , Widschwendter M , Stoeber K , Williams G 
Published: August 2014

Abstract
Using Phosphohistone-H3, a marker of cells in mitosis, we identified mitotic delay in 95% of invasive breast cancers with a significant proportion of cells in prophase/prometaphase (58%). This delay was seen in breast cancer tissues only with other malignancies and normal tissues showing a normal mitotic phase distribution (23% of mitotic cells in prophase/prometaphase). We could detect a clear mitotic delay phenotype already in 80% (55 out of 69 evaluable patients) of precursor ductal carcinoma in situ (DCIS) lesions. This strong phenotype has been concealed for over a century because tinctorial stains routinely used in diagnostic practice do not allow cells in prophase or prometaphase to be distinguished from interphase cells.
Promoter methylation analysis of candidate genes linked this defect to epigenetic silencing of the gene encoding Pregnancy-Associated Plasma Protein-A (PAPPA), a secreted protease. PAPPA silencing was highly prevalent in precursor lesions and invasive breast cancer. Experimental manipulation of PAPPA protein levels in human mammary epithelial cells and in breast cancer cell lines demonstrates that progression through early mitosis is dependent on PAPPA function, and that breast cancer cells become more invasive after PAPPA down regulation. We discovered that PAPPA regulates mitotic progression through its known role in modulating the IGF-1 signalling pathway, resulting in activation of the forkhead transcription factor FoxM1 which drives a transcriptional cluster of essential mitotic genes.
Our results identify PAPPA as a candidate tumour suppressor in breast cancer. PAPPA loss is an early event in breast tumourigenesis increasing tumour cell invasiveness and may contribute to the transition from precursor lesions to invasive disease.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-02-01.
Abstract P3-03-02: Na+,HCO3--cotransport is the major mechanism of cellular acid extrusion in human and murine breast cancer
Authors: Mele M , Lee S , Moreira J , Vahl P , Wielenga V , Jensen V , Pedersen S , Christiansen P , Aalkjær C , Boedtkjer E 
Published: August 2014

Abstract
High metabolism and insufficient blood supply are characteristics of cancer tissue, which in combination with biochemical changes favor glycolytic metabolism and result in prominent intracellular acid production. Although extracellular pH at the core of malignant tumors is as low as one unit below normal, intracellular pH (pHi) in tumor cells is typically normal or even slightly alkaline. Thus, cancer cells must possess efficient mechanisms of acid extrusion to eliminate the excess acid load.
We investigated the role of the Na+,HCO3–cotransporter NBCn1 (SLC4A7), which in recent genome-wide association studies has been linked to human breast cancer. Based on immunohistochemistry of tumor slices and immunoblotting of enzymatically isolated epithelial organoids, we found that NBCn1 expression is upregulated in human and murine primary breast carcinomas and metastases compared to normal breast tissue. The upregulation of NBCn1 was of similar or greater magnitude than that observed for the Na+/H+-exchanger NHE1, which has previously been implicated in cell migration, proliferation and malignancy. Measurements of pHi from slices of human and murine breast cancers and from malignant and normal breast epithelial organoids showed that Na+,HCO3–cotransport is the major mechanism of acid extrusion in the near-physiological pHi range. Na+/H+-exchange was important for acid extrusion only at very low pHi values. We furthermore found that Na+,HCO3–cotransport activity was substantially greater in malignant compared to normal breast epithelial organoids of both human and murine origin, while no apparent difference in Na+/H+-exchange activity was detected between cancer and normal breast tissue. Steady-state pHi was higher in the breast cancer tissue compared to normal breast epithelium in the presence of CO2/HCO3- but not in its nominal absence.
We propose that NBCn1 plays a major role for cellular acid extrusion and pHi regulation in human and murine breast cancer. The upregulated expression of NBCn1 and the functional importance of Na+,HCO3–cotransport for pHi regulation support a causative role for NBCn1 in breast cancer development or progression.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-03-02.
Abstract P3-03-05: Modulation of the metastatic propensity of triple-negative breast cancer cells harboring p53 mutations
Authors: Morrison BL , Tai JW , Bernal F 
Published: August 2014

Abstract
The mutation of p53 is implicated in the increased metastatic potential of triple-negative (ER—/PR—/Her2—) breast cancer (TNBC). The low survival rates of advanced metastatic cancer make it critical not only to understand the mechanisms underlying the functional implications of p53 mutations, but also to identify ways to regulate their impact in cancer cell physiology. A common gain-of-function activity of the mutant p53 protein is the enhancement of cell migration and invasion. We have found that a hydrocarbon-stapled p53 transactivation domain peptide (SAH-p53) designed to disrupt the interaction with p53 negative regulators HDM2 and HDMX also has the ability to inhibit the interaction between mutant p53 (mtp53) and HDM2/HDMX. In addition, SAH-p53 was found to inhibit the migration and invasion of MDA-MB-231 cells (mtp53), while exhibiting no alteration in their proliferative ability. The capacity of SAH-p53 to inhibit MDA-MB-231 cell migration was not altered in the absence of HDMX, suggesting an alternative mechanism of action for SAH-p53. The propensity of MDA-MB-231 cells to migrate and invade through Matrigel in response to transforming growth factor b (TGF-β), epidermal growth factor (EGF), hepatocyte growth factor (HGF), and platelet-derived growth factor (PDGF) was decreased by treatment with SAH-p53. Furthermore, increased concentrations of these growth factors displayed a synergistic effect with SAH-p53 in the inhibition of cell migration, suggesting cross-talk between receptor signaling and SAH-p53 activity. This effect was accompanied by an alteration in stress fiber formation and dissolution of focal adhesions. While the knockdown of mutant p53 in MDA-MB-231 cells significantly decreased migration on its own, inhibition of migration by SAH-p53 was not seen in the EGFR/p53-null MDA-MB-157 cells, suggesting a need for either the p53 or EGFR protein for the inhibitory activity of SAH-p53. Moreover, a SAH-p53-induced decrease in the total levels of EGFR and integrin beta1, together with alterations in actin stability, suggests a defect in receptor recycling, a process required for cell migration known to be modulated by an interaction between mutant p53 and p63. These data show that the use of the SAH-p53 peptide provides a novel avenue to study the molecular interactions that drive metastatic behavior originated by p53 gain-of-function mutations.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-03-05.
Abstract P3-03-12: Gamma-tocotrienol induces autophagy in malignant mammary tumor cells
Authors: Tiwari RV , Parajuli P , Sylvester PW 
Published: August 2014

Abstract
γ-Tocotrienol, a member of the vitamin E family of compounds, displays potent antiproliferative and apoptotic activity in a variety of cancer cell types at treatment doses that have little or no effect on normal cell viability or growth. Autophagy is a tightly regulated lysosomal self-digestive process that can either promote cell survival or be involved in type II cell death. Autophagy is induced in several diseases such as liver disease, neurodegeneration, Crohn's disease, aging, cancer, and metabolic syndrome. Autophagy is accompanied by the progressive development of vesicle structures from autophagomsomes (not acidic) to amphisome and autolysosomes (acidic). The execution and regulation of the autophagic program relies on several highly conserved autophagy-related genes (the Atg genes) that regulate the cannibalism of intracellular cytoplasm, proteins and organelles. The potential role of autophagy in mediating γ-tocotrienol-induced cytotoxicity is not currently understood. Therefore, studies were conducted to determine the effects of γ-tocotrienol on the induction of autophagy in various breast cancer cell lines. Mouse (+SA) and human (MCF-7 and MDA-MD-231) mammary tumor cells lines were exposed for an acute 24 h period to 20 or 40 μM γ-tocotrienol. Results showed that γ-tocotrienol treatment caused a relatively large increase in the accumulation of monodansylcadaverine (MDC)-labeled vacuoles, an early marker of autophagic compartment formation, in all mammary tumor cell lines. These cells also displayed an increased conversion of microtubule-associated protein 1A/1B-light chain 3 (LC3-I, the cytosolic form) to LC3-II (lapitated form associated with autophagosome), which is associated with the increased formation of autophagic vacuoles, followed by upregulation of Beclin-1. Treatment with γ-tocotrienol also caused a significant increase in the LC3II/LC3I ratio, a characteristic marker of autophagy, as compared to vehicle-treated control groups. Additional flow cytometery analysis showed that γ-tocotrienol treatment caused an increase in acridine orange staining, an indicator of autophagy, in all mammary cancer cell lines. In contrast, similar treatment of γ-tocotrienol on immortalized mouse (CL-S1) and human (MCF10A) normal mammary epithelial cell lines did not show significant accumulation of MDC–labeled vacuoles or the conversion of LC3-I to LC3-II. In addition, γ-tocotrienol-induced autophagy was also associated with a suppression in PI3K/Akt/mTOR signaling and the initiation of apoptosis as indicated by caspase activation in these mammary cancer cells. In summary, these finding suggest that γ-tocotrienol selectively induces autophagy in mouse and human mammary cancer cell lines and support a novel function of autophagy in promoting breast cancer cells death. This study was supported by grants from First Tech International Ltd., and the Malaysian Palm Oil Council.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-03-12.
Abstract P3-04-01: Discovery of distinct sub-groups of ER positive breast cancers by DNA repair expression profiling: Implications for patient stratification and personalization of therapy
Authors: Madhusudan S , Abdel-Fatah TMA , Russell R , Moseley P , Agarwal D , Mukherjee A , Ball G , Abbotts R , Perry C , Caldas C , Rakha EA , Chan S , Ellis IO 
Published: August 2014

Abstract
Background: The role of DNA repair in estrogen receptor (ER) positive breast cancer is largely unknown. We hypothesized that DNA repair dysregulation could lead to evolution of aggressive phenotypes with increasing resistance to endocrine therapy.
Methods: We immuno-profiled 1120 early stage ER positive breast tumours for Pol b, FEN1, APE1, XRCC1, SMUG1, PARP1, ATR, ATM, DNA-PK, BRCA1, CHK1, CHK2, TOPO2, and p53. Multivariate analysis was used to calculate a DNA repair prognostic index after controlling for other validated prognostic factors, confounders and adjuvant therapy. For additional validation, genomic expression as well as array CGH evaluation of key DNA repair genes was performed [discovery cohort (n = 128), external validation in Uppsala (n = 249) and METABRIC cohort (n = 1950)]. Neural network analysis was conducted in 249 tumours to map genetic interactions.
Results: DNA repair immuno-profiling stratified ER positive breast tumours into four distinct sub-groups with increasing aggressiveness and endocrine resistance (p = 1.6 × 10 −27). Subgroup 1 had the best breast cancer specific survival, subgroups 2 & 3 have intermediate breast cancer specific survival and sub-group 4 had the worst breast cancer specific survival (Table).
Survival analysis HR (95% CI)P ValuesSub-group 2 versus. Sub-group 11.6 (1.1-2.1)0.006Sub-group 3 versus. Sub-group 13.1 (2.3-4.3)1.5 × 10-12Sub-group 4 versus. Sub-group 15.7 (4.0-8.1)9.0 × 10−21
These distinct subgroups manifest progressively increasing tumour size, level of proliferation, de-differentiation, lymphovascular invasion, metastasis, altered apoptosis and increasing level of genomic instability (ps&lt;0.001). At the genomic level DNA repair gene dysregulation remains independently associated with poor outcome and resistance (ps&lt;0.001). Neural network analysis confirms interaction with genes involved in ER response.
Conclusion: This is the first and largest study with 20 years long term follow-up data to provide compelling evidence that DNA repair dysregulation impacts ER positive breast cancer pathogenesis and drives evolution of aggressive phenotypes. Our data could transform stratification and the personalization landscape for ER positive tumours.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-04-01.
Abstract P3-04-04: Amplification and overexpression of TLK2 promote genomic instability in invasive breast cancer
Authors: Kim J-A , CAO X , Tan Y , Wang X , Schiff R , Wang X 
Published: August 2014

Abstract
The accumulation of numerous chromosomal aberrations is a hallmark characteristic of invasive breast cancer (IBC). It is thus critical to find specific chromosomal aberrations that may drive breast cancer initiation and progression, particularly those that are drivers of the genomic instability. By integrative analysis of genomic data from The Cancer Genome Atlas (TCGA), we have nominated Tousled-Like Kinase 2 (TLK2) as a candidate oncogene target for IBC. Ultra-high resolution copy-number data from TCGA suggest that TLK2 was amplified in approximately 10% of IBC, which are more frequent in luminal B than luminal A tumors. These data also revealed that TLK2-high breast tumors harbor significantly more global copy-number aberrations than the TLK2 low-tumors. TLK2 is a nuclear serine/threonine kinase that serves as a cell cycle checkpoint regulating chromatin assembly, and in response to DNA damage, TLK2 can be inactivated by phosphorylation through the ATM-dependent pathway. We thus postulated that up-regulation of TLK2 may help cancer cells to surpass the cell cycle checkpoint upon DNA damage, which may promote genomic instability in breast cancer cells. To analyze the effect of TLK2 overexpression, we introduced an inducible expression vector containing the TLK2 open-reading frame into the MCF10A benign epithelial cells and the T47D breast cancer cells. As shown by fluorescence activated cell sorting (FACS), ectopic expression of TLK2 in these cells overcame the cell cycle checkpoint in response to the DNA damage induced by gamma irradiation. gamma-H2AX foci formation revealed increased DNA double strand breaks and prolonged DNA repair window after irradiation in the TLK2 overexpressing cells. Interestingly, immunofluorescence localized TLK2 to the nucleus of breast cancer cells, which was markedly enriched in DNA double-strand break foci (or gamma-H2AX foci). To examine the effect of TLK2 knockdown, the MCF7 and MDAMB361 breast cancer cells overexpressing TLK2 were transfected with different TLK2 siRNAs. TLK2 inhibition led to G1/S cell cycle arrest (FACS analysis), profound decrease in cell growth (MTT assay), and enhanced apoptosis (Annexin V assay) in the MCF7 and MDAMB361 breast cancer cells over-expressing TLK2. Together, this study supports the role of TLK2 deregulation in the increased genomic instability of TLK2-high breast cancers, and suggests its potential as an attractive therapeutic target.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-04-04.
Abstract P3-04-05: Amplification driven expression of KIAA0020, a PARP1 interacting gene, facilitates repair of replication associated DNA damage in triple-negative breast cancers
Authors: Grigoriadis A , Noel E , Weekes D , Shah V , Sidhu B , Gazinska P , Watkins J , Marra P , Tutt A 
Published: August 2014

Abstract
Approximately 25% of triple-negative breast cancers display increased copy number in the region of 9p24. Since several genes mapping to this genomic locus have been shown to be involved in the biology of triple-negative breast cancers, a copy number-dependent transcriptional influence of genes at 9p24 on the malignant phenotypes has been suggested. Given the limited options of targeted therapy for triple-negative breast cancer patients, further studies of genes located at this locus could therefore provide potential novel targets or companion biomarkers for this disease.
By integrating microarray-based DNA copy number and gene expression of genes located on 9p24 in 111 triple-negative breast cancers, we identified among a wider set of genes three hypothetical genes, KIAA0020, KIAA1432 and KIAA2026 whose expression was highly correlated with their copy number status. External validation through analysis of several comprehensive breast cancer cohorts, confirmed KIAA0020 as being highly abundant in basal-like/ triple-negative breast cancers. Involvement of KIAA0020 in PARP1 activity and the DNA damage response has previously been suggested. To elucidate KIAA0020's functional involvement in cell growth, cell cycle progression, apoptosis and DNA damage response in this subtype of breast cancer, breast cancer cell lines with and without increased 9p24 copy number levels were used as in vitro models. In cell lines with increased DNA copy number at 9p24, depletion of KIAA0020 expression selectively impaired growth causing an accumulation in S-phase and a decrease in cell proliferation. Furthermore, KIAA0020-silencing in such cell lines resulted in decreased repair of hydroxyurea induced replication associated DNA damage, accumulation of DNA double strand breaks and decreased occurrence of RAD51 and PAR foci, all pointing to a decreased repair of inactivated replication forks.
Taken together, our data supports the notion that genes of unknown function, residing in the 9p24 copy number aberrant region are involved in DNA repair and may thereby also contribute to the tumourigenesis of triple-negative breast cancers. A subset of such triple-negative tumours seemed to have developed a dependency on the expression of KIAA0020, a PARP1 interacting gene, for replication fork associated repair. Thus, greater understanding of KIAA0020's molecular function may provide additional information for patient selection with regards to DNA damaging chemotherapeutics or PARP inhibitors within triple-negative breast cancers.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-04-05.