bluuebunny/crossref_metadata_2025 huggingface dataset:
P2-02-10: Differential Targeting of the RB-Pathway To Expand the Therapeutic Index in the Treatment of Triple Negative Breast Cancer.
Authors: Knudsen ES , Dean J , Thangavel C , Ertel A , Witkiewicz AK , McClendon AK
Published: June 2012

Background: The retinoblastoma tumor suppressor (RB) is inactivated in a significant fraction of triple negative breast cancers (TNBC). RB loss is believed to contribute to tumor initiation and progression, and provocative data suggest that RB loss is associated with improved response to cytotoxic chemotherapy. Unfortunately, such therapies have significant side effects that impinge on patient quality of life. Here we explored the ability to specifically target RB loss in TNBC to expand the therapeutic index by protecting against undesired side-effects of chemotherapy.

Experimental Design: A combination of cell culture and xenograft models of triple negative breast cancer were used to evaluate how RB-status impinges on sensitivity to chemotherapy. These models were complemented by the analyses of clinical specimens from patients treated with chemotherapy. Parallel use of agents that activate RB function with high specificity were interrogated as potential tissue protectors to ameliorate side effect of chemotherapy.

Results: RB loss in preclinical models is associated with increased sensitivity to conventional cytotoxic chemotherapies that are frequently employed in the treatment of TNBC. The findings were recapitulated through the analyses of clinical specimens, and suggest that the loss of RB could be particularly useful in defining TNBC patients with improved response to chemotherapy. Combination studies of pharmacological activation of the RB pathway and cytotoxic chemotherapies commonly used to treat TNBC demonstrated that activation of RB can modulate the efficacy of cytotoxic compounds in the treatment of TNBC. Importantly, functional studies indicated that RB pathway activation limits cardiotoxicity associated with anthracycline based treatments and correspondingly improve cardiac function in animal studies.

Conclusions: Combined, these studies indicate that RB pathway status could be utilized in the clinic to direct combination treatments that would exploit the sensitivity of RB-deficient tumors to cytotoxic chemotherapies while simultaneously providing protection for normal tissues.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-02-10.
P2-05-02: PGC1, Peroxisome Proliferator Activated Receptor-gamma (PPAR-gamma) Coactivator-1, Is Necessary in PPAR-gamma Modulated Angiogenesis.
Authors: Jiang WG , Li X , Mansel RE
Published: June 2012

Background. Peroxisome proliferator activated receptor- gamma (PPAR-gamma), a nuclear hormone receptor, has been shown to be an important regulator of gene expression. PPAR-gamma agonists have been shown to have anti-cancer properties by ways of inducing expression of tumour suppressor genes. It has been indicated that this action of PPAR-gamma is manifested by forming a complex with the PPAR-gamma coactivators (PGC1 &2) and in association with other transcription factors such as SRC-1 and CREB binding proteins. Both PPAR-gamma and PGC-1 have been shown to be aberrantly expressed in human cancer including human breast cancer (1). PPAR-gamma also plays a role in regulating angiogenesis and that PPAR-gamma agonists have been shown to have anti-angiogenic functions. In the present study, we investigated the role of PGC-1 in PPAR-gamma mediated actions on vascular endothelial cells. Materials and methods. Mammalian expression systems for human full length PGC-1 ereonstructed. Anti-PGC-1 transgenes were constructed again using human mammalian expression vector in order to knock down PGC-1 transcript from the cells. Human vascular endothelial cell, HECV, was used in the study. Cell functions linked to angiogenesis including cell adhesion and cellular migration was evaluated using the electric cell impedance sensing method. PPAR-gamma agonists and antagonists were used in the cell models during the analyses.

Results. HECV cells weakly expressed PGC-1 and PPAR-gamma. Using the transgenes created, sublines over-expressing PGC1 (HECVPGC1exp) or with PGC-1 expression knockdown (HECVPGC1KD) were established. Loss of PGC1 showed marked increase in both adhesion and cellular migration, opposite was true forHECVPGC1exp cells. PPAR-gamma agonist, pioglitizone and ciglitizone, reduced the adhesion of control cells. In contrast, PPAR-gamma antagonist SR202 exhibited a concentration dependent stimulation of both adhesion and migration of the control cells. Knocking down PGC1 in endothelial cells rendered cells lost response to SR202.

Conclusions. PGC-1 is essential in during the modulation of endothelial cells by PPAR-gamma. Together with the aberrant expression of both PPAR-gamma and PGC-1 in breast cancer, it is concluded that PGC-1 is a central player in PPAR-gamma mediated action in both cancer cells and angiogenesis.

1. Jiang WG, Douglas-Jones A, Mansel RE. Expression of peroxisome-proliferator activated receptor-gamma (PPARgamma) and the PPARgamma co-activator, PGC-1, in human breast cancer correlates with clinical outcomes. Int J Cancer. 2003, 106(5):752–757.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-05-02.
P2-05-03: Is Breast Cancer Tryptase a Novel Anti-Angiogenetic Molecular Target?
Authors: Ranieri G , Gadaleta-Caldarola G , Misino A , Patruno R , Goffredo V , Di Lecce V , Vinciarelli G , Valerio P , Zito A , Gadaleta CD
Published: June 2012

Tryptase, a serine protease stored and released from mast cells granules has been identified as a new non-classical angiogenetic factor. Tryptase is an agonist of proteinase-activated receptor-2 a G protein involved in cellular proliferation and angiogenesis. On the other hand mast cells can release tryptase following c-Kit receptor activation. We have evaluated the correlations among the number of MCs positive to tryptase (MCDPT), the number of c-Kit receptor expressing cells (C-KREC) and microvascular density (MVD) in a series of 91 primary T1-3, N0-2 M0 female breast cancer by means of immunohistochemistry and image analysis methods. Six-micrometers thick serial sections of formalin-fixed and paraffin-embedded bioptic tumor samples were microwaved at 500 W for 10 min. and treated with a 3% hydrogen peroxide solution. Sections were incubated with primary antibodies: anti-tryptase (AA1; Dako, Glostrup, Denmark), anti-c-Kit receptor (A4502; Dako, Glostrup, Denmark) and anti-CD34 (QB-END 10; Bio-Optica Milan, Italy). In serial sections MVD, MCDPT and C-KREC were counted by means of image analysis (Quantimet 500 Leica) at x400 microscopic fields. Data demonstrated a significantly (r= ranging from 0.72 to 0.91; p: ranging from 0.001 to 0.003 by Pearson's analysis respectively) correlation between MVD, MCDPT and C-KREC to each other. Published in vitro data suggest that tryptase induce angiogenesis in vascular endothelial cells and breast cancer cells lines. According to these data we shown that MVD, MCDPT and C-KREC paralleled to each other suggesting a role in in vivo breast cancer angiogenesis. In this context the inhibition of c-Kit mast cells tryptase degranulation by several tyrosin kinase inhibitors might be evaluated in clinical trials. Finally available tryptase inhibitors such as gabexate mesilate or nafamostat mesilate might be evaluated in clinical trials as a new antiangiogenetic approach.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-05-03.
P2-06-03: Differential Expression of Breast Cancer-Associated Genes between Stage- and Age-Matched Tumor Specimens from African- and Caucasian-American Women Diagnosed with Breast Cancer.
Authors: Grizzle WE , Steg AD , He Q , Steciuk MR , Byan-Parker S , Johnson MR , Grunda JM
Published: June 2012

Background: Recent studies suggest that the poorer outcome of breast cancer patients observed in African-American women (AAW) may, in part, result from underlying genetic factors. The purpose of this study was to investigate gene expression differences between Caucasian-American women (CAW) and AAW that may contribute to this poorer prognosis.

Methods: The expression of genes involved in breast carcinoma prognosis, response to therapy, estrogen signaling, and tumor aggressiveness was assessed in age- and stage-matched CAW and AAW paraffin-embedded breast cancer specimens. The Wilcoxon-Mann-Whitney Test was used to identify genes with a significant difference in expression between CAW and AAW. To determine if the differentially expressed genes could segregate between the CAW and AAW, we performed semi-supervised principle component analysis (SSPCA).

Results: Twenty genes were differentially expressed between AAW and CAW. SSPCA incorporating these 20 genes separated AAW and CAW into two distinct groups. AAW were significantly (p < 0.05) more likely to display aberrations in G1/S cell-cycle regulatory genes, decreased expression of cell-adhesion genes, and low to no expression of ESR1, PGR, ERBB2 and estrogen pathway targets.

Conclusions: The gene expression differences identified between AAW and CAW may contribute to more aggressive disease, resistance to therapy, enhanced metastatic potential and poor clinical outcome. Impact: These findings support the hypothesis that breast cancer specimens collected from AAW display distinct genetic differences compared to similar tissues obtained from CAW. Additional population-based studies are necessary to determine if these genetic variations contribute to the highly aggressive and treatment-resistant breast cancer phenotype frequently observed in AAW.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-06-03.
P2-07-02: Germline Genetic Variants Disturbing the Let-7/LIN28 Double-Negative Feedback Loop Alter Breast Cancer Susceptibility.
Authors: Yu K-D , Shao Z-M , Chen A-X
Published: June 2012

Previous studies have shown that let-7 can repress the post-transcriptional translation of LIN28, and LIN28, in turn, could block the maturation of let-7, forming a double-negative feedback loop. In this study, we investigated the effect of germline genetic variants on regulation of the homeostasis of the let-7/LIN28 loop and breast cancer risk. We initially demonstrated that the T/C variants of rs3811463, a single nucleotide polymorphism (SNP) located near the let-7 binding site in LIN28, could lead to differential regulation of LIN28 by let-7. Specifically, the C allele of rs3811463 weakened let-7-induced repression of LIN28 mRNA, resulting in increased production of LIN28 protein, which could in turn downregulate the level of mature let-7. This effect was then validated at the tissue level in that the normal breast tissue of individuals with the rs3811463-TC genotype expressed significantly lower levels of let-7 and higher levels of LIN28 protein than those individuals with the rs3811463-TT genotype. Because previous in vitro and ex vivo experiments have consistently suggested that LIN28 could promote cellular transformation, we then systematically evaluated the relationship between rs3811463 as well as other common LIN28 SNPs and the risk of breast cancer in a stepwise manner. The first hospital-based association study (n = 2,300) demonstrated that two SNPs were significantly associated with breast cancer risk, one of which was rs3811463, while the other was rs6697410. The C allele of the rs3811463 SNP corresponded to an increased risk of breast cancer with an odds ratio (OR) of 1.25 (P = 0.0091), which was successfully replicated in a second independent study (n = 1,156) with community-based controls. The combined P-value of the two studies was 8.0 × 10−5. Taken together, our study demonstrates that host genetic variants could disturb the regulation of the let-7/LIN28 double-negative feedback loop and alter breast cancer risk.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-07-02.
P2-07-03: Collective Evidence Suggests Neutrality for BRCA1 V1687I, a Novel Sequence Variant in the Conserved THV Motif of the First BRCT Repeat.
Authors: Cortesi L , De Nicolo A , Medici V , Marino M , Turchetti D , Pradella LM , Rossi G , Parisini E , Federico M
Published: June 2012

Background: Unequivocal classification of BRCA1 and BRCA2 variants of uncertain significance (VUS) with respect to their effect on protein function is a challenge with consequent implications for clinical decision-making. Currently, integration of different types of evidence derived from independent sources appears to be the most reliable approach to help define disease relevance for each single VUS. During a routine screening for BRCA1 and BRCA2 mutations carried out by the Modena study group for familial breast and ovarian cancer we identified a novel BRCA1 sequence change (c.5178G>A) that causes a valine to isoleucine (V to I) substitution at position 1687. The sequence alteration was found in a patient diagnosed with early onset breast cancer and it was present neither in other breast/ovarian cancer families screened nor in unaffected control individuals. No co-occurrence of the variant with any known clinically relevant BRCA1 mutations was observed.

The C-terminally located BRCA1 V1687I lies in the conserved THV motif of the first BRCT repeat. Disease-causality has previously been suggested for two neighbouring sequence alterations, BRCA1 V1688del, whose repercussions on protein stability and function were also reported (De Nicolo et al., 2009), and BRCA1 H1686Q (Giannini et al, 2008). We aimed at garnering evidence that, together with family and genetic data, could help assess the clinical significance of the V1687I variant.

Methods: We employed a multimodal approach that included immunohistochemistry on tumor sections, in silico analyses, comparative structural modeling, and ascertainment of BRCT-mediated functional associations.

Results: Whereas tumor histology, receptor and HER2/neu status were compatible with a BRCA1-deficient phenotype, most algorithms we used to assess sequence and structure variation based on evolutionary conservation predicted the BRCA1 V1687I variant to be benign. In line with this prediction, analysis of the modeled BRCA1 V1687I BRCT domain did not reveal any major structural changes relative to the wild type counterpart and suggested that BRCA1 V1687I leaves the local architecture and overall stability of the protein largely unaltered. Consistently, the BRCA1 V1687I protein was properly expressed and localized to the nucleus, and it was still capable of binding BRIP1/FANCJ, CtIP and Abraxas, three BRCT-interacting, DNA damage response and repair partner proteins.

Conclusions: Based on our collected evidence, the BRCA1 V1687I amino acid change, although occurring in an evolutionary conserved region, does not seem to affect the function of the correspondingly encoded protein, and hence it is a likely benign sequence alteration.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-07-03.
P2-08-02: Magnetic Resonance Imaging as a Predictor of Pathologic Response in Patients Treated with Neoadjuvant Systemic Treatment for Operable Breast Cancer (TBCRC 017).
Authors: De Los Santos J , Cantor A , Mcguire K , Golshan M , Meric-Bernstam F , Horton J , Nanda R , Amos K , Forero A , Hudis C , Meszoely I , Hwang S
Published: June 2012

Background: Increased pathologic complete response (pCR) rates observed with neoadjuvant chemotherapy for invasive breast cancer has prompted interest in whether patients with pCR can be identified preoperatively and potentially spared the morbidity of surgery. This multicenter retrospective study was performed to determine the accuracy of preoperative MRI in predicting pCR in the breast and whether MRI performance differs by molecular subtype, histology, and treatment regimen.

Methods: 770 women from 8 institutions were retrospectively identified as having received neoadjuvant systemic therapy with MRI obtained at baseline and after completion of systemic treatment. Tumor phenotypes were defined on the basis of estrogen and progesterone receptor (ER/PR or HR) and HER2 receptor status. Univariate and multivariate analyses of factors influencing radiographic complete response (rCR) and pCR were recorded, with rCR defined as resolution of any abnormal enhancement, mass, or distortion on MRI, and pCR defined as resolution of both invasive disease and DCIS.

Results: rCR and pCR for the total group were 182/746 (24%) and 179/746 (24%), respectively, with the highest rate of pCR seen among the triple-negative (TN; 57/155; 37%) and HR-/HER2+ (38/101; 38%) subtypes. Covariates significantly associated with rCR included T stage (p=0.0002), tumor grade (p=0.005), IHC phenotype (p=0.005), and chemotherapy regimen (p<0.0001). On multivariate analysis, only tumor phenotype was independently associated with likelihood of rCR, with both TN (OR = 2.00, 95% CI 1.20−3.33) and HR-HER2+ (OR=2.30, 95% CI 1.09–4.83) more likely to achieve rCR than HR+HER- (reference group). Overall accuracy of MRI for prediction of pCR was 74%. Sensitivity, NPV, PPV, and accuracy differed significantly among tumor subtypes, with the greatest NPV in the HR-/HER2+ and TN subtypes (table1). Among patients with rCR, ER- status (OR=6.4, 95% CI 1.1 to 35.6), PR- status (OR=3.8, 95% CI 1.2 to 11.4), and tumor grade of 3 vs 1 or 2 (OR=2.49, 95% CI 1.22−5.07) were independently associated with likelihood of pCR. Discussion: MRI performance for predicting pCR in patients with invasive breast cancer receiving neoadjuvant systemic therapy differed significantly among breast cancer subtypes; however this difference is likely due to subtype differences in frequency of pCR and not to intrinsically better or worse MRI detection. The relatively low NPV of MRI following neoadjuvant systemic therapy does not support using MRI rCR alone to accurately identify those patients that can safely avoid surgery.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-08-02.
P2-08-03: Quantitative MRI for Noninvasive Prediction of Prognostic Markers in Breast Cancer.
Authors: Parsian S , Sun R , Kurland BF , Rahbar H , Allison KH , Specht JM , DeMartini WB , Lehman CD , Partridge SC
Published: June 2012

Background: Magnetic resonance imaging (MRI) is a valuable tool for assessing extent of breast cancer and monitoring treatment response. Quantitative measures by diffusion-weighted MRI (DWI) and dynamic contrast-enhanced (DCE) MRI reflect tumor cellularity and vascularity. Tumor grade and some histopathological markers, such as ER, PR, HER-2, Ki67 and P53, are prognostic factors that can also be associated with tumor cellularity and vascularity. DWI and DCE measures may therefore provide a noninvasive means for predicting disease prognosis and stratifying patients to appropriate therapies. The purpose of this study was to investigate the correlation between quantitative MRI features and prognostic pathological factors in patients with invasive breast cancer.

Methods: This IRB-approved retrospective study included patients with biopsy-proven invasive cancer who underwent 1.5T breast MRI (including DCE and DWI) from October 2005 to May 2006 prior to treatment. Pathology data was obtained from pre-treatment biopsy and intrinsic subtype classification was approximated by standard immunohistochemistry characteristics. After excluding cases with missing MRI or pathology data, the final study cohort included 41 invasive cancers (36 ductal and 5 lobular carcinomas) in 36 patients. MRI measures included lesion DCE kinetic features: peak initial enhancement (PE), percent rapid enhancement (RE), and percent washout (WO), and DWI normalized apparent diffusion coefficient values (nADC). Associations between imaging features and pathology markers, cancer grades and intrinsic subtypes were evaluated by Mann-Whitney U test and multivariate logistic regression.

Results: Results of univariate comparisons are summarized in Table 1. One or more DCE-MRI kinetic parameters were significantly predictive (p<0.05) of each of the histopathological markers with the exception of ER, which was marginally associated with WO (p=0.05). Each of the DCE kinetics parameters significantly discriminated grade III tumors from grades I and II and luminal A from luminal B and basal-like intrinsic subtypes. In multivariate regression, both PE and WO were significant independent predictors of tumor grade (p=0.0094, p=0.0005, respectively). WO and nADC were significant independent predictors of PR status (p=0.0054, p=0.0027), while PE was the only significant independent predictor of both Ki67 (p=0.014) and intrinsic subtype (p=0.015).

Conclusion: This preliminary study suggests that quantitative MRI measures are associated with prognostic tumor markers and may provide valuable noninvasive characterization of tumor biology. Larger prospective studies are needed to validate our findings.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-08-03.
P2-08-07: Ex-Vivo High Resolution MRI of Sentinel Lymph Nodes Following Subcutaneous Injection of Superparamagnetic Iron Oxide Nanoparticles.
Authors: Douek M , ter Beek O , Johnson L , Pankhurst Q , Parikh J , Schaeffter T , Purushotham A , Charles-Eduards G
Published: June 2012

Background: Superparamagnetic iron oxide (SPIO) enhanced axillary MRI is a promising novel imaging modality that could be used to characterize sentinel nodes non-invasively. In order to better characterize lymph nodes and evaluate their morphological features, we imaged nodes ex-vivo using high resolution MRI, following a pre-operative subcutaneous injection of SPIO.

Material and methods: Prior to surgery patients received a circumareolar injection of SPIO (Endorem, Guerbet, Paris) into the upper outer quadrant of the affected breast. Sentinel lymph nodes excised during surgery were transported to the imaging department fresh. Nodes were placed in glass tubes and scanned using a Bruker 9.4T MRI system (T2 mapping: turbo spin echo, 16 equi-spaced TEs from 7.1 to 113.6 ms, TR = 1616 ms. T2* mapping: gradient echo, 6 equi-spaced TEs from 3.5 to 21 ms, TR = 1000 ms, flip angle = 30 degrees. Diffusion-weighted: spin echo, b-values 0 and 1000 s/mm2, TE = 18 ms, TR = 6500 ms.). Slice thickness was 1 mm with an in plane spatial resolution of 100μm. Image analysis was undertaken using Osirix (v3.8, 64-bit).

Results: A total of 40 nodes were successfully imaged, excised from 14 patients. The internal architecture of nodes was clearly seen and in the 3 involved nodes, a macrometastasis was identified. Three patients received a 4ml injection of SPIO and 11 patients, a 2ml injection. More SPIO deposition was seen within nodal sinuses following 4ml of SPIO, but there was no significant decrease in mean T2 value. Four nodes were re-imaged following formalin fixation and nodal architecture was unchanged with a trend towards an increase in mean T2 values within nodes. SPIO was identified in all sentinel nodes.

Discussion: Ex-vivo MRI with subcutaneous SPIO contrast, is a useful method for imaging and characterization of sentinel nodes. A better understanding of ex-vivo features is a useful aide to understanding the morphological features seen following in-vivo SPIO enhanced axillary MRI.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-08-07.
P2-09-04: Near Infra Red Quantum Dots as Novel Probes for Sentinel Lymph Node Biopsy.
Authors: Rizvi SB , Yang SY , Bala R , Shirin G , Seifalian AM , Keshtgar M
Published: June 2012

Background: Sentinel Lymph Node Biopsy (SLNB) is a standard procedure in breast cancer surgery. The current tracers for SLNB including the blue dye and radiocolloid, have various limitations like anaphylactic reaction to the dye and exposure of radioactivity to both patients and staff. Quantum dots (QDs) are fluorescent nanoparticles (2-10nm in diameter), with unique photophysical properties like enhanced photostability and size tunable emission wavelengths, that can potentially replace the current tracers for SLNB. QDs emitting in the Near Infra Red (NIR) range of the electromagnetic spectrum can be tracked in deep tissues as biological tissues are transparent to NIR wavelengths (700-2000nm). We have developed Near Infra Red emitting Quantum Dots (NIR QDs) as alternative probes for SLNB and set up a live NIR imaging system to track them in deep tissues.

Materials and Methods: NIR emitting QDs based on CdTeHg were synthesized by a one pot aqueous method and characterized using Transmission Electron Microscopy (TEM), UV-V is*** spectrometry and photoluminescence studies. 100μl of QDs (1mg/ml) were co-injected intradermally with blue dye into the hind legs of rat models (n=4) and compared to controls (n=4) which were injected with blue dye only. The procedure was conducted under inhalational anaesthesia using isofluorane and rats were monitored for hemodynamic instability for a period of 2 hrs after injection. QDs were tracked using a live NIR imaging system including an excitation light of 630nm, emission filter of 850nm and a Hamamatsu Orca 2 UV-Vis-NIR thermoelectrically cooled CCD camera.

Results: NIR QDs had a core diameter of 7nm on TEM and emitted at 860nm upon excitation with a 630nm light source. Within 3 minutes of an intradermal injection QDs entered the lymphatic tracts. The lymphatics converged to the groin and a small surgical incision at this site revealed the underlying sentinel lymph node with minimal dissection. The rats remained hemodynamically stable throughout the duration of the procedure with no significant difference in comparison with the controls.

Conclusion: NIR emitting QDs can be used for accurate localisation of the SLN prior to surgical incision, making this an even more minimally invasive procedure and possibly an office based procedure in the future. The nanosize, surface chemistry and deep tissue visibility of these novel nanoprobes allow relentless possibilities for in vitro and in vivo molecular and cellular imaging. NIR QDs can be conjugated to biomolecules for cancer localisation, detection of micrometastasis and image guided targeted drug delivery of chemotherapeutic agents. Further studies to investigate their in vivo biodistribution are in progress to take this technology one step closer to clinical application.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-09-04.
P2-10-06: Prospective Ultrasonographic Prediction of Sentinel Lymph Node Metastasis by Real-Time Virtual Sonography Constructed with Three-Dimensional Computed Tomography-Lymphography in Breast Cancer Patients.
Authors: Yamamoto S , Maeda N , Yoshimura K , Oka M
Published: June 2012

Background: Real-time virtual sonography (RVS) systems display virtual multiplanar reconstruction (MPR) images obtained from three-dimensional (3D) computed tomography (CT)-lymphography (LG), significantly improving preoperative detection of sentinel lymph nodes (SLNs). The purpose of this study was to prospectively evaluate SLN metastasis using an RVS system.

Methods: We identified SLNs in 73 clinically node-negative breast cancer patients using an RVS system to display in real time a virtual MPR obtained from CT volume data corresponding to the same cross-sectional image from ultrasonography (US). CT volume data were obtained using our original 3DCT-LG, which accurately detects SLNs in breast cancer. We then prospectively attempted to predict metastasis to SLNs. SLN metastases were assessed by measuring the cortex thickness in the presence of a visible hilum. We defined suspected SLN metastases as SLNs with a cortex thickness of at least 2.5 mm on the basis of our preliminary data. All patients underwent SLN biopsy and SLN metastases were examined pathologically with serial 2.0-mm-thick multiple slices.

Results: Suspected SLN metastases were identified in 24 of 73 patients, and 13 of these 24 patients were pathologically positive. The remaining 49 patients displayed no suspected SLNs, and 46 of these 49 were pathologically negative. Sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy of measuring cortical thickness for predicting metastatic involvement of SLNs were 81, 81, 54, 94, and 81%, respectively.

Conclusion: If cortical thickness of the SLN is less than 2.5 mm, SLN metastasis is unlikely to be present. If cortical thickness of the SLN is at least 2.5 mm, preoperative fine-needle aspiration cytology may be recommended to verify the possibility of SLN metastasis.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-10-06.
P2-10-07: Triple-Negative Breast Cancer May Have Ultrasonographic Features Mimicking Nonmalignant Lesions.
Authors: Wojcinski S , Farrokh A , Schmidt J , Hillemanns P , Degenhardt F
Published: June 2012

Background

Triple-negative breast cancer (TNBC) is known to have unique molecular, clinical and pathologic characteristics. Histological studies illustrate high mitotic counts, geographic necrosis, pushing borders of invasion, and stromal lymphocytic response. These growth patterns may also affect the appearance of TNBC in ultrasound.

Our study evaluates the ultrasonographic features of TNBC according to the ACR BI-RADS®-US classification system and compares these features with non-TNBC.

Materials and methods: Data of 385 consecutive breast cancer cases were collected from our hospital database. Digitally recorded ultrasound images were available for 292 patients. These images were interpreted according to the BI-RADS® system by an examiner blinded to the patients’ characteristics and histological results. The ultrasonographic features of TNBC (n=45) and non-TNBC (n=247) were compared using Fisher's exact test.

Results: TNBC was more common in younger patients and exhibited higher tumor grades and more advanced tumor stages. Focusing on the ultrasound features, TNBC was more likely to exhibit round or oval shape (35.5% versus 25.9% in non-TNBC) and the margin of TNBC was more frequently described as microlobulated (48.9% versus 37.7% in non-TNBC) instead of angular or spiculated. In TNBC the echogenic halo was significantly less often observed (46.7% versus 64.4% in non-TNBC, p=0.0302) and we found less architectural distortions (65.5% versus 84.3% in non-TNBC, p=0.0341). Regarding the posterior acoustic features, an enhancement was significantly more often observed in TNBC (26.7% versus 13.0% in non-TNBC, p=0.0391).

Discussion: TNBC and non-TNBC seem to have different ultrasonographic features. This can be explained by the unique pathologic profile of this breast cancer subtype. As some of the distinct ultrasound criteria of TNBC are associated with benign masses, TNBC may mimic nonmalignant lesions. Being familiar with these features can avoid false-negative classification of TNBC.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-10-07.
P2-10-10: A Precision Comparison of Breast Ultrasound Images between Different Time Phases by Imaging Fusion Technique Using Magnetic Position Tracking System.
Authors: Nakano S , Fujii K , Yorozuya K , Yoshida M , Fukutomi T , Arai O , Mitake T
Published: June 2012

Purpose: We developed a real-time virtual sonography (RVS) in which realtime ultrasound (US) images and reconstructive virtual US images of the same cross-section are synchronized based on US volume data obtained on the same monitor using magnetic position tracking system (US-RVS). The purpose of this study was to evaluate the accuracy of US-RVS to compare breast US images between different time phases.

Materials and Methods: Between March 2010 and April 2011, US-RVS was performed in 108 consecutive patients with 112 target lesions for US (mean lesion size: 12 mm, 54 malignant and 58 benign). We used US-RVS system which consisted of sonography equipment, magnetic field generator, magnetic sensor, and workstation. To assess the accuracy of the US-RVS, we analyzed the sonographic re-identification rate of target lesions in different time phases.

Results: Among the 112 target lesions, 105 (94%) lesions were re-identified by US-RVS. The remaining occult 7 (6%) lesions were included one DCIS and 6 fibrocystic changes in terms of the histological type, and one mass lesion and 6 nonmass like lesions in terms of morphological feature. US-RVS enabled us to precisely compare arbitrary cross-sections of US images in any direction between different time phases independent of the operator's skill.

Conclusion: US-RVS, which requires no contrast medium and involves no radiation exposure, can be a useful modality for temporally tracking regions of interest using US.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-10-10.
P2-11-01: Validation of Predictive DNA Damage Response (DDR) Assay in Luminal B and Basal-Like Breast Cancers.
Authors: Rodriguez AA , Mao Y , Zhao H , Wong S , Chang JC
Published: June 2012

Background: We previously published a 69-gene DDR microarray signature that predicted for pathologic complete response (pCR) to anthracycline chemotherapy in women with basal-like breast cancer in two clinical studies1. Here, we sought to validate this predictive signature in independent data sets of breast cancers, selecting for basal-like and luminal B subtypes. We also customized a low density qRT-PCR array for use on formalin-fixed paraffin embedded tissue that will allow for prospective validation and clinical use.

Methods: Six independent validation sets were selected with known response to DNA damaging agents, containing either anthracyclines or cisplatin2-7. One independent data set with known response to the microtubulin agent docetaxel (non-DNA damaging) was used. 8 Using PAM50 genes, the tumors were first classified according to the molecular subtype. The predictive value of the 69-gene DDR assay was then correlated with known pathologic response, and the receiver operating curve determined.

We then performed qRT-PCR of these 69 genes with 5 controls, and correlated the expression of these genes with microarray RNA values in an additional 50 basal tumors. The data for individual genes was normalized, combined, and then hierarchically clustered.

Results: In the 170 basal tumors treated with DNA damaging agents, a high score predicted response in basal-like tumors. A, p< 0.05. Conversely, for a non-DNA-damaging therapy, a high score significantly predicted for lack of response. B. In the 116 luminal B cancers, the DDR-assay also predicted for response to DNA damaging agent containing regimens with AUCs ranging from 0.67 to 0.80. C.

Microarray of the 69 DDR gene expression values was compared with Ct values by q-RTPCR low density array for 50 paired samples. High concordance between these two platforms (48/50 samples) was observed.

Conclusion: We have identified a robust predictive DDR assay that predicts for response to the DNA damaging agents, doxorubicin, epirubicin, and cisplatin in multiple studies, but not for docetaxel therapy. Future studies are underway to test for prediction of benefit of PARP1 inhibitor in basal-like and luminal B breast cancer.

References:

(1) Rodriguez AA et al: Breast Can Res Treat 123:189–96 (2) Tabchy A et al: Clin Cancer Res 16:5351–61 GSE 20271 (3) Farmer P et al: Nat Med 15:68–74, 2009 GSE 4779 (4) Popovici V et al: Breast Can Res 12:R5 GSE 20194 (5) Silver DP et al: J Clin Oncol 28:1145–53 GSE18864 (6) Desmedt C et al: J Clin Oncol 29:1578–86 GSE16446 (7) Iwamoto T et al: JNCI 264 GSE 23988 (8) Gluck S et al: Breast Can Res GSE 22358

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-11-01.
P2-11-07: Expression of Selected Predictive Markers in African American Women with Atypical Hyperplasia of the Breast.
Authors: Bandyopadhyay S , Cote M , Visscher DW , Ruterbusch J , Albashiti B , Alosh B , Frost MH , Hartmann LC , Fehmi RA
Published: June 2012

Invasive breast carcinoma in African American (AA) women differs significantly from their Caucasian (CA) counterparts in its incidence, morphology and outcome. These tumors are more likely to be high grade, hormone receptor negative, present at a younger age and at a higher stage. Evaluation and a better understanding of precursor lesions may help delineate the mechanisms underlying the development of breast cancer in these two groups. Atypical hyperplasia (AH) in the breast has been associated with an increased risk of developing cancer (relative risk∼4.0). Risk stratification of these women by identification of predictive biomarkers would be beneficial for optimal patient care. In our study we evaluated the expression of the following prognostic biomarkers: estrogen receptor (ER), Cyclooxygenase-2 (COX-2) enzyme and Ki-67 in AH in a cohort of AA women with benign breast biopsies.

AA women with benign breast biopsies from years 1997–2000 were retrieved from our departmental database. Clinical and follow up data was obtained from the SEER database. The hematoxylin and eosin (H & E) slides for these cases were reviewed by 2 pathologists, who were blinded to the outcome, and those with atypia were included in this study. Paraffin blocks were retrieved for immunohistochemical (IHC) analysis and standardized scoring methods applied.

A total of 1608 AA women had benign breast biopsies during the study period. We performed IHC analysis on 37 (2.3%) who were diagnosed with atypia (25 cases of atypical ductal hyperplasia (ADH) and 12 cases of atypical lobular hyperplasia (ALH)). Increased COX-2 expression was seen in 19 of 28 (67.8%) cases with AH. Of these, 13 of 19 cases (68.4%) were of ADH and 6 of 9 cases (66.7%) were of ALH. Twenty of 25 cases had a high expression of ER overall. Of these, 15 of17 (88.2%) of the positive cases was in the ADH category and 3 of 7 (42.8%) was in the ALH group.

Of 32 cases, only 3 cases showed a proliferation rate of > 2% (9.4%) with Ki-67 IHC stain. All of these cases belonged to the ADH (21) category. In summary, the majority of AH cases showed increased COX-2 expression, although no differences were observed between lobular and ductal lesions. In contrast, ADH lesions appeared to exhibit increased reactivity for ER compared to ALH. Similarly, although rare, more ADH cases showed an increased proliferation rate compared to ALH. From our data, COX-2 and ER might be of prognostic significance in AA patients with AH. Larger studies with follow up are needed to understand this disease further.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-11-07.
P2-12-07: Pooled Analysis of Outcomes of T1a/bN0, HER2−Amplified Breast Cancer.
Authors: Amir E , Seruga B , Ocaña A , Carlsson L , Bedard P
Published: June 2012

Background: Breast tumors with HER2 amplification have a worse prognosis than those with normal HER2 expression. This finding is independent of tumor size and other classical prognostic factors used in the adjuvant setting. The prognosis of node negative, sub-centimeter (T1a/bN0) tumors is usually excellent. However, little is known about the prognostic impact of HER2−amplification in this group. This study therefore, aimed to evaluate the relative and absolute prognostic impact of HER2−amplification in T1a/bN0 tumors.

Materials and Methods: Published data from studies assessing the outcomes of patients with HER2−amplified, node negative, T1a/bN0 tumors were included in a pooled analysis. Odds ratios (OR), 95% confidence intervals (CI) and absolute risks were computed for recurrence and distant recurrence at 5 years. Pooled hazard ratios (HR) for disease-free survival (DFS), were also assessed.

Results: A total of 3 case-control studies were included in the analysis and comprised 485 patients with HER2−amplified breast cancer (57.3% were also hormone receptor positive) and 1096 patients with HER2−normal disease (82.2% were hormone receptor positive). Among the HER2−amplified group, 4.1% received trastuzumab and 18.6% received chemotherapy. In the HER2−normal group, 4.3% received chemotherapy Estimated median follow-up was 5.7 years. HER2−amplification was associated worse DFS (HR = 2.60, 95% CI 1.53−4.41, p<.001) and increased odds for recurrence at 5 years (OR = 3.79, 95% CI 2.35−6.10, p<.001). There was a non-significant trend towards increased odds of distant recurrence at 5 years (OR = 2.51, 95% CI 0.82−7.67, p=.11). Compared with HER2−normal cancers, those with HER2−amplification showed lower absolute probability of recurrence-free survival at 5 years (90.1% vs. 94.6%, p<.001) and distant recurrence-free survival at 5 years (95.1% vs. 97.6%, p<.001). Among HER2−amplified cancers, tumor size 0.6−1.0cm (T1b) was associated with a trend for higher odds of recurrence at 5 years compared with those 0.5cm or smaller (T1a, pooled OR = 1.58, 95% CI 0.96−2.60, p=.07).

Conclusions: HER2−amplification is associated with worse outcome in T1a/bN0 tumors. However, recurrence-free and distant recurrence-free survival at 5 years is excellent in this group, particularly in those with T1a tumors. These data question the role of adjuvant chemotherapy and trastuzumab in these patients unless associated with other high risk features. A differentially lower risk for distant recurrence suggests the possible role for more aggressive local therapy such as surgery and/or radiation therapy.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-12-07.
P2-12-24: Resumption or Persistence of Menstruation after Cytotoxic Chemotherapy Is a Poor Prognostic Factor for Disease Free Survival in Premenopausal Patients with Early Breast Cancer.
Authors: Park IH , Han H-S , Lee KS , Kang HS , Lee S , Kim SW , Jung SY , Shin KH , Ro J
Published: June 2012

Background : We investigated the relationship between resumption or persistence of menstruation after chemotherapy and disease free survival (DFS) in premenopausal patients with early breast cancer.

Patients and methods : A total of 843 patients diagnosed with a stage I to III breast cancer between March 2001 and December 2006 were included in this study. All patients received cytotoxic chemotherapy after surgery; 411 (48.8%) with anthracycline based, 416 (49.3%) with anthracycline and taxane containing, and 16 (1.9%) with other regimens. We reviewed the medical records with a long term follow-up.

Results : The median age of patients was 41 years (range, 21–54 years) and the median follow-up duration was 6.2 years (range, 0.7−10.4 years).

Of all, 632 (75%) patients were hormone receptor (HR) positive who received tamoxifen therapy upon completion of chemotherapy. The chemotherapy induced amenorrhea (CIA) rate was 78.1% (n=658) and 52.4% (n= 442) experienced the resumption of period during the long term follow-up. One hundred two (12.1%) patients had persistent menstruation without CIA. The disease free survival (DFS) was significantly affected by the younger age (≤ 35 years) (HR=1.58, [95% CI, 1.10−2.70], P=0.014), advanced stage (stage 3) (HR=4.45, [95% CI, 3.17−6.25], P<0.001), HR negativity (HR=2.21, [95% CI, 1.57−3.12], P<0.001), HER2 positivity (HR=1.56, [95% CI, 1.04−2.34], P=0.032), and the resumption or persistent period (HR=2.03, [95% CI, 1.42−2.91], P<0.001). HR negativity (HR=2.03, [95% CI, 1.43−2.90], P<0.001), advanced stage (HR=4.40, [95% CI, 3.12−6.21], P<0.001), and the resumed or persistent period (HR=1.85, [95% CI, 1.24−2.77], P=0.002) were remained significant factors for DFS on multivariate analysis.

Conclusions : A considerable proportion of premenopausal patients treated by chemotherapy experienced resuming period after CIA. The resumption or persistence of menstruation was a poor prognostic factor for disease free survival in premenopausal patients with early breast cancer.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-12-24.
P2-13-01: Gene Profiling of Whole Blood May Identify Patients with BRCA Mutations.
Authors: Mina LA , Gokmen-Polar Y , Goswami C , Storniolo AM , Li L , Badve S , Sledge GW
Published: June 2012

Background:The BRCA1 and the BRCA2 proteins play a role in DNA repair and confer genomic stability to the cell. Identifying BRCA mutation carriers has become an important tool for prevention as well as guiding therapy in cancer patients. We proposed to test the hypothesis that gene expression analysis of peripheral whole blood can reliably detect these mutations.

Materials and methods: Following IRB approval, 10cc of blood was collected from 36 women (BRCA1 (n=8), BRCA2 (n=9), Hereditary breast cancer without BRCA (FAM) (n=7), sporadic breast cancer (SPO) (n=11)). 3 of BRCA1 and 5 of BRCA2 samples were from women without cancer. Following RNA extraction (using the method described by Beekman et al) and quality assessment, Illumina® Whole-Genome DASL™ microarray (Human Ref-8 BeadChips) analysis was performed. The raw data was normalized and analyzed using Partek® Genomic Suite. Differentially expressed genes were identified using ANOVA analysis. Geneset specific supervised analysis was performed to visualize the inherent similarities and differences in the gene expression amongst different groups for 1) DNA repair and 2) Immune-system-related genes. Ingenuity Pathway Analysis (IPA) was performed to interpret the data in the context of biological processes, pathways and networks.

Results: Twenty-nine of the 87 immune-related genes were up-regulated in BRCA1 and BRCA2 groups compared to SPO or FAM groups; these included IL7R, CD53, CD2, CD48 and HLA-DRA. Twenty-five of the 79 DNA repair genes were up-regulated in BRCA1 and BRCA2; these included FANCC, RAD51L3, MSH2, MSH6 and PCNA. In IPA analysis, the comparison of BRCA1 vs. REST (BRCA2 + FAM + SPO) showed a strong immunologic signal, with the top altered biological processes including “Immunologic disease”, “Infection mechanism”, “Immune cell trafficking” and “cell-mediated immune response “. The top 5 canonical pathways also reflected a similar pattern and included “iCOS-iCOSL Signaling in T Helper Cells”, “OX40 Signaling Pathway”, “Calcium-induced T Lymphocyte”, “Apoptosis Regulation of IL-2 Expression in Activated and Anergic T Lymphocytes” and “Protein Ubiquitination Pathway”. When BRCA2 was compared with the REST (BRCA1 + FAM + SPO), a much weaker signal was noted with none of the canonical pathways being significantly altered. PAM analysis showed that a set of 16 genes could differentiate the BRCA patients from the rest with an error rate of 5%. Further validation of this geneset is being performed.

Conclusion: Gene profiling in whole blood may offer an easy, reliable and inexpensive way to identify patients with BRCA mutation. Further studies are currently underway to validate our results in a larger patient population.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-13-01.