Abstract P2-04-02: Comparison of DNA methylation patterns in normal breast tissue from women with and without breast cancer

BACKGROUND: Increasing evidence suggests that epigenetic mechanisms play critical roles in the development of breast cancer. However, precise DNA methylation signatures associated with breast cancer susceptibility remain unknown. We sought to compare DNA methylation changes in the normal breast tissue of women with and without breast cancer to identify patterns of aberrant DNA methylation in women with breast cancer.

METHODS:Samples of normal breast tissue were collected from four cohorts of women: age < 50 years with and without breast cancer, and age ≥50 years with and without breast cancer. Normal breast tissue from healthy women was obtained from the Komen Tissue Bank at IU Simon Cancer Center and from women presenting for reduction mammoplasty at Yale New Haven Hospital. Normal breast tissue from women with breast cancer was obtained from patients undergoing adjuvant total mastectomy at Yale Breast Center. DNA was extracted using Qiagen AllPrep Universal kit. Raw data files in idat format were imported to Partek Genomics Suite 6.6 for normalization and differential methylation analysis. Raw intensities were normalized using With Array Normalization (SWAN) method. Principal component analysis (PCA) were performed as quality control. Differentially methylated loci (DML) between control and breast cancer groups were detected when False discovery rate (FDR) < 0.05 and fold change > 1.5. Functional enrichment analysis of genes with DML in the gene body were conducted using METACORE™. Pathways with FDR < 0.05 were selected.

RESULTS: Ninety-three normal breast tissue samples from 89 subjects were analyzed (breast cancer=40, unaffected=53). Comparison of DNA methylation patterns between women with and without breast cancer revealed 200 DMLs. The majority of DMLs (186) were hyper-methylated in breast cancer patients, and 48 DMLs locate in enhancers of genes. 170 DMLs locate in 134 genes, enriched in two pathways: (1) Cell adhesion_Endothelial cell contacts by junctional mechanisms, and (2) Neurophysiological process_Constitutive and regulated NMDA receptor trafficking. Genes associated with cell adhesion and cell contacts included: ACTN2, GJA4, GJA7 and MAGI1. Two hyper-methylated loci were found in enhancers of ACTN2. In addition, one hyper-methylated locus in GJA4, one hyper-methylated and one hypo-methylated loci in GJA7, and two hyper-methylated loci in MAGI1 were detected in breast cancer patients. Genes associated with NMDA receptor trafficking include: TPK1, ADCY4 and LIN7C. One and two loci were found in TPK1 and ADCY4, respectively, that were hyper-methylated in normal breast tissue from cancer patients in the gene body, while a hypo-methylated locus in breast cancer patients was identified in LIN7C.

CONCLUSIONS: Comparison of DNA methylation patterns of normal breast tissue from women with and without breast cancer reveal specific mechanistic pathways and genes that are differentially methylated in women with breast cancer. DNA methylation of normal breast tissue deserves further study as a potential biomarker for breast cancer risk stratification and may lend new insight into mechanisms of breast cancer development.

Citation Format: Hofstatter EW, Zhu Y, Horvath S, Chagpar AB, Wali VB, Bossuyt V, Storniolo AM, Hatzis C, Patwardhan G, Von Wahlde M-K, Butler M, Epstein L, Stavris K, Sturrock T, Au A, Kwei S, Pusztai L. Comparison of DNA methylation patterns in normal breast tissue from women with and without breast cancer [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-04-02.

Abstract P5-22-22: Breast tumor location in BRCA mutation carriers and implications for prevention

Introduction:

Close to 65% of BRCA mutation carriers do not choose prophylactic mastectomy, despite their high breast cancer risk. Breast reduction mammoplasty is a surgical technique shown to reduce breast cancer risk and can be modified to target specific areas of the breast. We wondered if a majority of tumors in BRCA mutation carriers would be confined to one quadrant, allowing for the use of targeted cosmetic mammoplasty as a novel method of risk reduction.

Methods:

We reviewed imaging reports on 103 consecutive patients with BRCA mutations and invasive breast cancer, and categorized tumor location by quadrant. Tumors spanning >1 quadrant were classified as being in both. Bilateral cancers were counted separately. Categorical variables were compared with the chi-squaredtest.

Results:

Mean age at breast cancer diagnosis was 44 years with mean tumor size of 2.2 cm (0.1-7cm). 92% of tumors were invasive ductal carcinoma, 46% were hormone receptor positive, 10% Her2 positive, and 44% triple negative. 70% of the tumors were unicentric. Tumors were significantly more likely to be in the upper outer quadrant whether or not multicentric tumors were included in the analysis (p<0.00001). Her2 positive tumors were more likely to be multicentric than other subtypes (p=0.021).

Conclusions:

More than half of breast cancers in BRCA mutation carriers form in the upper outer quadrant, suggesting that removing this quadrant through breast reduction mammoplasty could significantly reduce breast cancer risk. For women who are not ready for prophylactic mastectomy, this data supports an intermediate risk reduction step instead of only offering surveillance.

Citation Format: Hosseini A, Esserman LJ, Wallace AM, Au A, Mukhtar RA. Breast tumor location in BRCA mutation carriers and implications for prevention [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-22-22.

Reliability and Validity of the “Extended - Hurt, Insult, Threaten, Scream” (E-Hits) Screening Tool in Detecting Intimate Partner Violence in Hospital Emergency Departments in Hong Kong

Objectives

To assess the reliability and validity of a brief screening instrument, “E-HITS” (Extended - Hurt, Insult, Threaten, Scream), for detecting female intimate partner violence (IPV) in Hong Kong emergency departments (EDs).

Method

Quantitative data were collected from a victim group (n=110) and a control group (n=116). Statistical properties of the instruments were analysed to ascertain its internal consistency, test/re-test reliability, concurrent validity and discriminant validity.

Results

Cronbach's alpha was 0.90 for the E-HITS. Two-week test/re-test reliability was 0.71 (p<0.001). Respondents' scores on the E-HITS positively correlated with those on psychological aggression, physical assault, sexual coercion and injury scales, and negatively correlated with the negotiation scale of the revised Conflict Tactics Scale at a statistically significant level. Subsequent Receiver Operating Characteristic (ROC) curve analysis revealed that E-HITS reached a sensitivity of 98.2% and a specificity of 94.8% at a cut-off of 8.5. The overall accuracy of the E-HITS indicated by the area under curve (AUC) in the ROC is 0.991.

Conclusion

These results show that the E-HITS has good internal consistency, test/re-test reliability, as well as concurrent and discriminant validity. The E-HITS is a valid and reliable tool for screening intimate partner violence in Hong Kong EDs.

IRFinder: assessing the impact of intron retention on mammalian gene expression

Intron retention (IR) occurs when an intron is transcribed into pre-mRNA and remains in the final mRNA. We have developed a program and database called IRFinder to accurately detect IR from mRNA sequencing data. Analysis of 2573 samples showed that IR occurs in all tissues analyzed, affects over 80% of all coding genes and is associated with cell differentiation and the cell cycle. Frequently retained introns are enriched for specific RNA binding protein sites and are often retained in clusters in the same gene. IR is associated with lower protein levels and intron-retaining transcripts that escape nonsense-mediated decay are not actively translated.

Targeting the LOX/hypoxia axis reverses many of the features that make pancreatic cancer deadly: inhibition of LOX abrogates metastasis and enhances drug efficacy

Pancreatic ductal adenocarcinoma (PDAC) is one of the leading causes of cancer-related mortality. Despite significant advances made in the treatment of other cancers, current chemotherapies offer little survival benefit in this disease. Pancreaticoduodenectomy offers patients the possibility of a cure, but most will die of recurrent or metastatic disease. Hence, preventing metastatic disease in these patients would be of significant benefit. Using principal component analysis (PCA), we identified a LOX/hypoxia signature associated with poor patient survival in resectable patients. We found that LOX expression is upregulated in metastatic tumors from Pdx1-Cre Kras(G12D/+) Trp53(R172H/+) (KPC) mice and that inhibition of LOX in these mice suppressed metastasis. Mechanistically, LOX inhibition suppressed both migration and invasion of KPC cells. LOX inhibition also synergized with gemcitabine to kill tumors and significantly prolonged tumor-free survival in KPC mice with early-stage tumors. This was associated with stromal alterations, including increased vasculature and decreased fibrillar collagen, and increased infiltration of macrophages and neutrophils into tumors. Therefore, LOX inhibition is able to reverse many of the features that make PDAC inherently refractory to conventional therapies and targeting LOX could improve outcome in surgically resectable disease.

Human breast cancer invasion and aggression correlates with ECM stiffening and immune cell infiltration

Tumors are stiff and data suggest that the extracellular matrix stiffening that correlates with experimental mammary malignancy drives tumor invasion and metastasis. Nevertheless, the relationship between tissue and extracellular matrix stiffness and human breast cancer progression and aggression remains unclear. We undertook a biophysical and biochemical assessment of stromal-epithelial interactions in noninvasive, invasive and normal adjacent human breast tissue and in breast cancers of increasingly aggressive subtype. Our analysis revealed that human breast cancer transformation is accompanied by an incremental increase in collagen deposition and a progressive linearization and thickening of interstitial collagen. The linearization of collagen was visualized as an overall increase in tissue birefringence and was most striking at the invasive front of the tumor where the stiffness of the stroma and cellular mechanosignaling were the highest. Amongst breast cancer subtypes we found that the stroma at the invasive region of the more aggressive Basal-like and Her2 tumor subtypes was the most heterogeneous and the stiffest when compared to the less aggressive luminal A and B subtypes. Intriguingly, we quantified the greatest number of infiltrating macrophages and the highest level of TGF beta signaling within the cells at the invasive front. We also established that stroma stiffness and the level of cellular TGF beta signaling positively correlated with each other and with the number of infiltrating tumor-activated macrophages, which was highest in the more aggressive tumor subtypes. These findings indicate that human breast cancer progression and aggression, collagen linearization and stromal stiffening are linked and implicate tissue inflammation and TGF beta.

Clinical impact of ABCC1 and ABCC2 genotypes and haplotypes in mediating imatinib resistance among chronic myeloid leukaemia patients

WHAT IS KNOWN AND OBJECTIVE

The introduction and success of imatinib mesylate (IM) has brought about a paradigm shift in chronic myeloid leukaemia (CML) treatment. However, despite the high efficacy of IM, clinical resistance develops due to a heterogeneous array of mechanisms. Pharmacogenetic variability as a result of genetic polymorphisms could be one of the most important factors influencing resistance to IM. The aim of this study was to investigate the association between genetic variations in drug efflux transporter ABCC1 (MRP1) and ABCC2 (MRP2) genes and response to IM in patients with CML.

METHODS

We genotyped 215 Malaysian patients with CML (comprising of two groups with 108 IM resistant and 107 IM responsive) for polymorphisms of ABCC1 (2012G>T and 2168G>A) and ABCC2 (-24C>T, 1249G>A and 3972C>T) genes. Genotype, allele and haplotype frequencies were compared between two groups of patients. Patients with CML were further stratified according to their clinical response to IM into those having cytogenetics and molecular responses, and the associations with genotypes were evaluated.

RESULTS AND DISCUSSION

We observed no significant differences in the distribution of any of the tested genotypes between the investigated groups. However, on evaluating the risk association, ABCC2 T₋₂₄ G₁₂₄₉ T₃₉₇₂ haplotype was found to be associated with IM resistance (P = 0·046). These results suggest that haplotype variants -24T and 3972T might be associated with lower expression of ABCC2 protein and reduced transport activity and hence might be contributing to development of IM resistance.

WHAT IS NEW AND CONCLUSION

Our results suggest the ABCC2 T₋₂₄ G₁₂₄₉ T₃₉₇₂ haplotype was associated with imatinib resistance. However, the evidence is as yet insufficient to establish this haplotype as a predictive biomarker for response to the drug.

Abstract S2-06: Extracellular matrix stiffness modulates tissue inflammation to promote breast tumor aggression

Tumor progression is influenced by the dynamic interplay between the genetically-modified epithelium and the associated microenvironment. We previously showed that the extra-cellular matrix (ECM) progressively stiffens as mammary tumors evolve, and that stiffening the ECM promotes malignant transformation while inhibiting ECM stiffening reduces tumor progression (Levental et al., 2009; reviewed in Butcher et al., 2009). Yet breast cancers also exhibit elevated influx of inflammatory cells and tissue inflammation promotes tumor progression by fostering angiogenesis and enhancing tumor cell growth and motility (Ruffell et al., 2011). Tumor-associated macrophages additionally stimulate stromal fibroblasts, implying that tissue inflammation could promote malignancy by stiffening the ECM. To address this possibility, we explored the relationship between ECM tension and macrophages in human breast cancer and during mammary tumor development in transgenic mice. Using fresh and archived tissue samples, we quantified a progressive increase in ECM remodeling and stiffening as human breast tumors and mouse mammary cancers developed. We found that the ECM associated with triple negative breast cancers was almost twice as stiff as the ECM adjacent to ER+/PR+ tumors and that ECM stiffness correlated significantly with increased numbers of infiltrating activated macrophages. Consistently, we established a positive correlation between tumor progression, elevated mechanosignaling, ECM stiffness and tissue inflammation in both human and mouse tissue. However surprisingly, when macrophages were depleted from the mammary glands of MMTV-PyMT tumors, ECM tension did not change. Instead we found that inhibiting lysyl oxidase activity to decrease collagen cross-linking and ECM stiffness reduced the activation state of the macrophages within the mammary glands of 14-week old mice. Consistently, in vitro studies showed that ECM tension potentiates the expression of pro-inflammatory chemokines and increases levels of phosphoStat3 and that ECM tension directly modifies macrophage polarity. These findings suggest that ECM tension may promote malignancy either by directly regulating macrophage activity or indirectly through enhancing expression of pro-inflammatory chemokines. Further studies are now underway to explore these findings and to clarify their impact on tumor progression and response to therapy.

Acknowledgements: supported by W81XWH-05-1-0330 and R01 CA138818-01A1 to VMW, 1U01 ES019458-01 to VMW and ZW, and P50 CA 58207 to JG, VW, SH and LC, U54CA143836-01 to JL and VW, and Susan G. Komen for the Cure PSF12230246 to IA.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr S2-06.

p53 status determines the role of autophagy in pancreatic tumour development

Macroautophagy (hereafter referred to as autophagy) is a process in which organelles termed autophagosomes deliver cytoplasmic constituents to lysosomes for degradation. Autophagy has a major role in cellular homeostasis and has been implicated in various forms of human disease. The role of autophagy in cancer seems to be complex, with reports indicating both pro-tumorigenic and tumour-suppressive roles. Here we show, in a humanized genetically-modified mouse model of pancreatic ductal adenocarcinoma (PDAC), that autophagy's role in tumour development is intrinsically connected to the status of the tumour suppressor p53. Mice with pancreases containing an activated oncogenic allele of Kras (also called Ki-Ras)--the most common mutational event in PDAC--develop a small number of pre-cancerous lesions that stochastically develop into PDAC over time. However, mice also lacking the essential autophagy genes Atg5 or Atg7 accumulate low-grade, pre-malignant pancreatic intraepithelial neoplasia lesions, but progression to high-grade pancreatic intraepithelial neoplasias and PDAC is blocked. In marked contrast, in mice containing oncogenic Kras and lacking p53, loss of autophagy no longer blocks tumour progression, but actually accelerates tumour onset, with metabolic analysis revealing enhanced glucose uptake and enrichment of anabolic pathways, which can fuel tumour growth. These findings provide considerable insight into the role of autophagy in cancer and have important implications for autophagy inhibition in cancer therapy. In this regard, we also show that treatment of mice with the autophagy inhibitor hydroxychloroquine, which is currently being used in several clinical trials, significantly accelerates tumour formation in mice containing oncogenic Kras but lacking p53.

A gene therapy approach to eliminate HIV-1-infected cells

The ideal therapy for HIV infection requires a method to eliminate all HIV-harboring cells in the infected individual. The authors are developing an HIV-specific promoter to drive the expression of suicide genes that would induce cell death specifically in HIV-infected cells. The authors constructed a promoter that is 100-fold more responsive to the HIV transcriptional activator, Tat, than cellular transcription factors, using a plasmid expressing luciferase under the control of the mutated LTR promoter.

Diagnosis and treatment of osteoporosis before and after admission to long-term care institutions

SUMMARY

Bisphosphonate treatment rates were examined before and after admission to long-term residential care. Bisphosphonate treatment rates were low (16%) pre-admission but doubled after long-term residential care admission (30%). Men were very undertreated for osteoporosis, while a history of falls with injury was not associated with treatment.

INTRODUCTION

To determine the rates and independent correlates of bisphosphonate treatment in elderly residents before and after admission to long-term care (LTC) institutions.

METHODS

Information was collected from records of 421 residents of four LTC institutions in Edmonton, Alberta, Canada. Osteoporosis-related diagnoses, treatments, and risk factors including falls in LTC and any adulthood fractures were abstracted. Osteoporosis was defined by physician diagnosis or documented fractures of the hip, spine, or upper extremity. Multivariable analyses were undertaken to determine factors independently associated with bisphosphonate treatment.

RESULTS

Mean age was 84 ± 8 years and 290 (70%) were female. Overall, 142 (34%) had previous fractures, 170 (41%) had physician-diagnosed osteoporosis, and 227 (54%) residents met the study's clinical definition of osteoporosis. Of those with osteoporosis, 44 (19%) were men. Before admission, 36 (16%) patients with osteoporosis were treated with bisphosphonates; after admission another 31 (14%) were started on bisphosphonates by LTC physicians. Women were far more likely than men to start bisphosphonate treatment [30 (97%) women vs. 1 (3%) man, adjusted odds ratio (aOR) = 9.20 (95% confidence intervals 1.2,70.5)]. Falls with injury were common [72/227 (31%)] but not associated with bisphosphonate treatment (adjusted p value > 0.5).

CONCLUSION

Rates of pre-admission bisphosphonate treatment were low, but did double after LTC admission. Women were almost ten times more likely to start bisphosphonate treatment than men, although one fifth of those with documented osteoporosis were men. Although falls cause most fractures, a history of falls with injury was not associated with bisphosphonate treatment. Our findings suggest that targeting men and residents with falls for treatment with bisphosphonates might be warranted.

P1-03-01: ECM Stiffness and Breast Tumor Histology and Treatment Phenotype

Currently, the extent of local surgery and radiation for breast cancer is not guided by biological or anatomical principles, and the optimal volume of treatment is not defined. Local tumor progression is strongly influenced by a dynamic interplay between the genetically-modified epithelium and the associated cellular and non-cellular stroma (Butcher, 2009; Levental, 2009). The extracellular matrix (ECM) is modified in breast tumors and data indicate that the ECM stiffens progressively as mammary tumors evolve and enhancing ECM stiffness promotes mammary tumorigenesis while inhibiting ECM stiffening reduces tumor progression. However, the degree and extent of local stromal changes, and their clinical impact in breast cancer evolution and treatment remain unclear. This has led us to predict that the desmoplastic stroma surrounding breast tumors reflects tumor phenotype and behavior and can be characterized by biophysical metrics of the ECM stroma and molecular signatures of the breast epithelium. Accordingly, we hypothesize that these features may be integrated into a stromal phenotype that can be developed as a predictive tool. To test this concept we used a rigorous biomechanical and biochemical analysis of mastectomy specimens from women with various stages and histology phenotypes of treated and non-treated breast cancer to explore the relationship between ECM stiffness, mechanotransduction and tumor behavior. The goal of the study was to characterize stromal changes as a function of tumor stage and histology phenotype as well as before and after chemotherapy by measuring biophysical and topological features of the ECM and biochemical and molecular signatures of the mammary epithelium. The objective was to determine if there is a significant association with tumor histology phenotype that could be integrated to generate a stromal phenotype. Egan sections of were acquired from breast tissue containing benign and invasive ER positive and negative carcinoma and from treated and non-treated patients. All tissues were subjected to IHC histological and mechanosignaling analysis (H&E; 397FAK; Lysyl Oxidase; phosphomyosin) and biomechanical assessment (Atomic Force Microscopy; Structured Illumination Polarized Imaging; Two Photon Imaging). Preliminary data were consistent with prior in vitro and in vivo studies and showed that there was a significant increase in ECM stiffness as the tissues transitioned from normal to an invasive lesion with the highest stiffness being located at the tumor edge (∼2-4 folds greater). Intriguingly, we observed that ER negative tumors were substantially stiffer than ER positive tumors (50% increase in upper 10-percentile) and that there were tracks of ECM stiffness that correlated with orientated parallel collagen fibers and ECM birefringence. Moreover, we quantified a significant decrease in ECM stiffness following treatment (40% lower) with the most striking reduction in ECM tension being noted in ER negative patient tissues who demonstrated the most robust response. This study should lead to a deeper understanding of the nature of breast cancer stroma and its role in tumor phenotype and response to therapy.

Supported by: NCI SPORE P50 CA058207 to VMW, CP, & SH; U01 ES019458-02 to ZW; NCI R01 CA138818-01A1 to VMW; & U54 CA143836-01 to VMW & JL.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-03-01.

Concordance between the 21-gene recurrence score (RS) and the 70-gene profile (MP) in breast cancer (BC) patients (pts)

13

Background: Genomic assays are increasingly incorporated into treatment planning for pts with early stage BC to provide prognostic and/or predictive information. MP is a validated predictor of recurrence risk (RR) in pts without any treatment and RS is a validated predictor of RR in pts treated with 5 years of hormonal therapy (HT). Because concordance between RS and MP is largely unknown, we analyzed concordance in untreated pts that had both tests performed.

Methods: Data are from 50 early stage BC pts treated at 4 US Oncology practices and the University of California, San Francisco. We used linear regression to test whether clinical features were related to discordance, measured as part of the gamma statistic.

Results: Median age was 52.5 years, 16% (8 pts) had micro or macroscopic nodal involvement, and 66%, 30%, and 4% of pts had stage I, II, and III disease, respectively. All pts had estrogen receptor positive disease and 2 pts had HER2 overexpression by IHC or FISH. Concordance of MP and RS is shown below. Clinical features, including tumor size, grade, and HER2 were not significantly related to discordance. Gamma concordance was 0.64 (95% CI 0.28 to 0.98, p=0.0013).

Conclusions: Concordance is high, mostly due to agreement in low risk scores. Five cases are truly discordant (MP low/RS intermediate or high) based on predicted outcomes. The 11 cases with high-risk MP with low risk RS may reflect endocrine sensitivity to 5 years of HT, or true discordance. Our identification of discordance should stimulate research to further clarify biology and elucidate the drivers of different types of risk. Large studies are underway to refine risk definition and treatment recommendations.

[Table: see text]

Contribution of a common variant in the promoter of the 1-α-hydroxylase gene (CYP27B1) to fracture risk in the elderly

CYP27B1 encodes mitochondrial 1α-hydroxylase, which converts 25-hydroxyvitamin D to its active 1,25-dihydroxylated metabolite. We tested the hypothesis that common variants in the CYP27B1 promoter are associated with fracture risk. The study was designed as a population-based genetic association study, which involved 153 men and 596 women aged 65-101 years, who had been followed for 2.2 years (range 0.1-5.5) between 1999 and 2006. During the follow-up period, the incidence of fragility fractures was ascertained. Bone ultrasound attenuation (BUA) was measured in all individuals, as were serum 25-hydroxyvitamin D and PTH concentrations; 86% subjects had vitamin D insufficiency. Genotypes were determined for the -1260C>A (rs10877012) and +2838T>C (rs4646536) CYP27B1 polymorphisms. A reporter gene assay was used to assess functional expression of the -1260C>A CYP27B1 variants. The association between genotypes and fracture risk was analyzed by Cox's proportional hazards model. We found that genotypic distribution of CYP27B1 -1260 and CYP27B1 +2838 polymorphisms was consistent with the Hardy-Weinberg equilibrium law. The two polymorphisms were in high linkage disequilibrium, with D' = 0.96 and r² = 0.94. Each C allele of the CYP27B1 -1260 polymorphism was associated with increased risk of fracture (hazard ratio = 1.34, 95% CI 1.03-1.73), after adjustment for age, sex, number of falls, and BUA. In transient transfection studies, a reporter gene downstream of the -1260(A)-containing promoter was more highly expressed than that containing the C allele. These data suggest that a common but functional variation within the CYP27B1 promoter gene is associated with fracture risk in the elderly.

Association of Proliferating Macrophages with High Grade, Hormone Receptor Negative Breast Cancer

Macrophages, a key cell in the inflammatory cascade, have been associated with poor prognosis in cancers, including breast cancer. Tumor associated macrophages (TAM) have also been shown to play a role in invasion and metastases. In this study, we investigated the role of a subset of macrophages known as proliferating macrophages (promacs) in breast cancer. We examined the relationship between promacs and clinico-pathologic characteristics such as tumor size, grade, lymph node metastasis, hormone receptor status, molecular subtype, and survival. This study was conducted at two independent institutions (University of California, San Francisco and University of Chicago) using two independent cohorts of patients with breast cancer. Formalin-fixed, paraffin-embedded sections and/or tissue microarrays were double-stained with anti-CD68 (a macrophage marker) and anti-PCNA (a proliferation marker) antibodies. The number of total macrophages as well as promacs per high power field were counted. Molecular subtypes were determined from gene expression array analyses. Outcomes were available for a subset of the cases and Kaplan Meier survival curves were generated.Tumor tissue from two different cohorts of patients with breast cancer were stained and analyzed at two independent institutions. In both studies, promac density was significantly correlated with higher grade, hormone-receptor negative tumors, and a basal-like subtype. In contrast there was no correlation between numbers of promacs and tumor size, stage, or number of involved lymph nodes. The presence of increased promacs was a significant predictor of survival in these treated patients. Proliferating macrophages are more abundant in high grade tumors, and predict a worse outcome, independent of stage and grade. These findings, corroborated at two independent institutions, suggest that the presence of promacs is associated with tumor progression and increased promac density may serve as a prognostic indicator for poor outcomes. Novel therapies that are able to target and halt the activity of promacs may be a promising strategy for the treatment of promac rich tumors.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3042.

Fluvastatin has biologic effects on stage 0 and 1 breast cancer

Abstract #4122

Introduction: Statins are safe, reduce cardiovascular risk, and impact pathways critical to cancer progression. We and others have shown lipophilic statins cause apoptosis and growth suppression in vitro and in vivo, and though epidemiologic data are mixed, statin effect appears most evident in estrogen receptor (ER) negative or grade 3 disease. To look for a direct biologic effect of lipophilic statins, we conducted a perioperative pilot window trial in women with breast cancer (BC).&#x2028; Methods: 40 subjects with stage 0,1 BC were randomized to high dose (80mg/day) or low dose (20mg/day) fluvastatin for 3-6 weeks prior to surgery. Paired tissue (core biopsy and surgical specimen), peripheral blood and MRI were obtained. Primary endpoint was Ki-67 (proliferation) change. Secondary endpoints included cleaved caspase-3 (CC3, apoptosis), longest diameter (LD) by MRI, and C-reactive protein (CRP) change. Subgroup analyses was planned by grade (3 vs. 1,2), statin dose; and ER status. Immunohistochemistry (IHC) on paraffin tissue used standard streptavidin biotin methods. A single breast pathologist reviewed all slides; a single radiologist read all MRIs, both blinded to timepoint.&#x2028; Results: Median serum cholesterol decreased by 16% (-23% and -12% for high and low dose, respectively p=0.012), indicating drug effect and compliance. 29 patients had sufficient tumor for paired IHC, 14 and 15 were grade 3 and 1,2, and 10 and 19 were ER - and +, respectively. In grade 3 (73% of which were ER-) vs. 1,2 tumors, there was a significant decrease in Ki-67, -7.2% (interquartile range (IQR) -13.4%, 0% ) vs. -0.3% (IQR -3%, .8%), respectively, p=0.04. CC3 (apoptosis) increased, 60% vs. 13% for grade 3 vs. 1,2 tumors, respectively, p=0.015. ER- and ER+ cases had a similar reduction in Ki67 with a median drop of 2% (IQR -13.4%, 1%) and 1.2% (IQR -6.6%,0.8%), respectively, p=0.56. While CC3 was increased in ER- vs. + (55% vs. 29%), the difference was not statistically significant. There was no dose dependent effect on Ki-67or CC3.There was no evidence of Ki67 or CC3 change when all grades were analyzed together (median drop 1.2%) and no change in CRP. Of 14 subjects with paired MRIs, 4 grade 3 cases showed a significant decrease in LD, marked ductal dilatation and increased necrosis.with statin exposure.&#x2028; Conclusions: A lipophilic statin, fluvastatin, reduced cholesterol and had measurable biologic changes (reduced proliferation, size and increased apoptosis) in stage 0,1 BC after only 3-6 weeks of exposure, specifically in the grade 3 subset. Results support the study of statins for chemoprevention for women at risk for or with stage 0 grade 3 BC, where new agents are needed.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4122.

Illness-related factors, stress and coping strategies in relation to psychological distress in HIV-infected persons in Hong Kong

This study examined the relationships among illness-related factors, stress, coping strategies and psychological distress in HIV-infected persons in Hong Kong (N=118). Multiple regression analyses were used to examine the models of psychological distress as a function of demographic factors, illness-related factors, psychosocial stressors and coping. Results showed that positive thinking was inversely related to psychological distress and avoidance was associated with higher level of anxiety. However, the use of problem solving was found to be inversely related to anxiety. Results are discussed in the context of Chinese culture and the service in Hong Kong.

Clinical case seminar: Fibroblast growth factor 23: a new clinical marker for oncogenic osteomalacia

The phosphate-wasting condition, oncogenic osteomalacia, is problematic to diagnose and manage clinically due to difficulty in locating the causative tumor. Fibroblast growth factor 23 (FGF23) has recently been implicated in the pathogenesis of oncogenic osteomalacia. In this case the patient presented with clinical features typical of oncogenic osteomalacia. Removal of an angiolipoma from the thigh did not correct the clinical or biochemical abnormalities. Subsequent identification and removal of a benign giant cell tumor in the pubic ramus, however, did result in normalization of his symptoms and signs. Positive staining for FGF23 protein by immunohistochemistry was demonstrated in the giant cell tumor, but not in the angiolipoma. The serum concentration of FGF23 was elevated in preoperative serum, then normalized after removal of the giant cell tumor. Expression of both FGF23 mRNA and protein was demonstrated in the giant cell tumor tissue, and FGF23 mRNA expression and renal phosphate uptake inhibitory activity were also detected in cultured giant cell tumor cells. This case provides further evidence for the involvement of FGF23 in the pathogenesis of oncogenic osteomalacia and for the utility of serum FGF23 measurement and immunohistochemical detection of FGF23 in the diagnosis and clinical management of this condition.

The role of visual and auditory temporal processing in reading irregular and nonsense words

In the present study, the role of rapid visual and auditory temporal processing in reading irregular and nonsense words was investigated with a group of normal readers. One hundred and five undergraduates participated in various visual and auditory temporal-processing tasks. Readers who primarily adopted the phonological route in reading (nonsense-word readers) showed a trend for better auditory temporal resolution but readers who primarily adopted sight word skills (irregular-word readers) did not exhibit better visual temporal resolution. Both the correlation and stepwise multiple-regression analyses, however, revealed a relationship between visual temporal processing and irregular-word reading as well as a relationship between auditory temporal processing and nonsense-word reading. The results support the involvement of visual and auditory processing in reading irregular and nonsense words respectively, and were discussed with respect to recent findings that only dyslexics with phonological impairment will display temporal deficits. Further, the temporal measures were not effective discriminants for the reading groups, suggesting a lack of association between reading ability and the choice of reading strategy.

Effects of 32P radioactive stents on in-stent restenosis in a double stent injury model of the porcine coronary arteries

BACKGROUND

The major limitation of coronary stenting remains in-stent restenosis, due to the development of neointimal proliferation. Radioactive stents have demonstrated the ability to reduce this proliferation in the healthy nonatherosclerotic porcine animal model. However, inhibition of tissue proliferation in the in-stent restenotic lesion in a porcine model is not well characterized. The objective of this study was to examine the efficacy and safety of the 32P radioactive stent for the treatment of in-stent restenosis in a double stent injury model of the porcine coronaries.

METHODS AND MATERIALS

Eighteen coronary arteries in 9 pigs underwent nonradioactive stent (8 mm in length) implantation. Thirty days after the initial stent implantation, a 32P radioactive stent (18 mm in length) with an activity of 0 and 18 microCi was implanted to cover the initial stent. The swine were killed 30 days after the second stent implantation. Histomorphometric analysis was performed for vessel area (VA), stent strut area (SSA), intimal area (IA), and lumen area (LA).

RESULTS

Injury scores, VA, SSA, and LA were similar among the control and radiated groups. Neointimal formation was significantly reduced after placement of radioactive stents as compared to control in both the overlapped (0.93 +/- 0.12 vs. 1.31 +/- 0.51 mm(2), p < 0.05) and nonoverlapped segments (1.14 +/- 0.21 vs. 1.91 +/- 1.04 mm(2), p < 0.05). The smooth muscle cell index in the neointima was reduced. Intimal fibrin was increased in the radiated group as compared to the control (p < 0.01 respectively).

CONCLUSIONS

32P radioactive stents may be safe and effective in reducing neointimal formation leading to in-stent restenosis. Longer follow-up will be required to examine whether these positive findings can be maintained.

"Edge Effect" of (32)p radioactive stents is caused by the combination of chronic stent injury and radioactive dose falloff

BACKGROUND

Radioactive stents have been reported to reduce in-stent neointimal thickening. An unexpected increase in neointimal response was observed, however, at the stent-to-artery transitions, the so-called "edge effect." To investigate the factors involved in this edge effect, we studied stents with 1 radioactive half and 1 regular nonradioactive half, thereby creating a midstent radioactive dose-falloff zone next to a nonradioactive stent-artery transition at one side and a radioactive stent-artery transition at the other side.

METHODS AND RESULTS

Half-radioactive stents (n=20) and nonradioactive control stents (n=10) were implanted in the coronary arteries of Yucatan micropigs. Animals received aspirin and clopidogrel as antithrombotics. After 4 weeks, a significant midstent stenosis was observed by angiography in the half-radioactive stents. Two animals died suddenly because of coronary occlusion at this mid zone at 8 and 10 weeks. At 12-week follow-up angiography, intravascular ultrasound and histomorphometry showed a significant neointimal thickening at the midstent dose-falloff zone of the half-radioactive stents, but not at the stent-to-artery transitions at both extremities. Such a midstent response (mean angiographic late loss 1.0 mm) was not observed in the nonradioactive stents (mean loss 0.4 to 0.6 mm; P< 0.01).

CONCLUSIONS

The edge effect of high-dose radioactive stents in porcine coronary arteries is associated with the combination of stent injury and radioactive dose falloff.

Inhibition of phorbol ester-induced AP-1-DNA binding, c-Jun protein and c-jun mRNA by dietary energy restriction is reversed by adrenalectomy in SENCAR mouse epidermis

The aim of this study was to determine the effects of 40% dietary energy restriction (DER) relative to ad libitum feeding on AP-1-DNA binding and expression of c-Jun protein and c-jun mRNA in SENCAR mouse skin treated with acetone or 12-O-tetradecanoylphorbol 13-acetate (TPA). The role of the glucocorticoid hormone corticosterone (CCS) was investigated by adding CCS or vehicle control to the drinking water of adrenalectomized mice. AP-1-DNA binding, measured by electrophoretic mobility shift assay, showed that TPA treatment for 4 h increased AP-1-DNA binding by 2-fold over acetone controls (P < 0.05) and that DER reduced basal and TPA-induced AP-1-DNA binding in comparison with ad libitum fed groups in sham-operated mice (P < 0.05). TPA treatment increased c-Jun protein levels in control fed mice (4-fold) and in DER mice (2-fold) over basal levels 4 h post-treatment (P < 0.05). Analyzed over all groups, DER reduced c-Jun protein levels (P < 0.01) and this effect was reversed by adrenalectomy. TPA induction of c-jun mRNA was also reduced by DER compared with ad libitum fed mice (P < 0.05). Adrenalectomy and CCS supplementation demonstrated that the effects of DER on AP-1-DNA binding were mediated in part by CCS. Measurement of blood plasma CCS concentrations showed that: (i) DER increased CCS 5-fold over ad libitum fed mice in sham-operated animals (P < 0.05); (ii) adrenalectomy decreased CCS over sham-operated mice (P < 0.05); (iii) TPA treatment had no effect on CCS. Blood plasma IGF-I concentrations were unaffected by CCS modulation or TPA treatment but were decreased by DER compared with ad libitum fed mice (P < 0.05). Thus, dietary energy restriction may inhibit cancer mechanistically by reducing overall AP-1 transcription through a process that is mediated in part by glucocorticoid hormones.

Dietary energy restriction inhibits ERK but not JNK or p38 activity in the epidermis of SENCAR mice

Ongoing studies in our laboratory have demonstrated that dietary energy restriction (DER) inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced AP-1 transcription factor binding to DNA in the epidermis of SENCAR mice. To dissect the specific signal transduction pathways through which DER inhibits the AP-1:DNA binding, we analyzed the activities of three major MAP kinases that lead to the induction of AP-1. The changes in ERK1 and ERK2 protein expression and phosphorylation were further characterized by western blot analysis. Female SENCAR mice were pre-fed ad libitum (AL) or 40% DER diet for 8-10 weeks. The kinase activities in mouse epidermis were determined by immune complex kinase assays at 0.5, 1, 4, or 6 h following treatment with 3.2 nmol TPA to the shaved dorsal backs. ERK activity at 1 h post-TPA treatment was nearly 5-fold (P< 0.005) above basal levels in AL mice while the increase was abolished in DER mice. The TPA-induced ERK activity in AL mice was accompanied by increased phosphorylation of ERK1 and ERK2 (P< 0.05), which was abrogated in DER mice. In addition, DER mice exhibited reduced expression of total ERK1 and ERK2 and higher proportions of ERK1 and ERK2 phosphorylation in comparison with AL mice (P<0.05). JNK activity was decreased at 1 and 6 h but increased at 4 h (P<0.05) post-TPA treatment. TPA did not change p38 kinase activity at the time points tested. Neither JNK nor p38 activity was altered by DER. Taken together, our results indicated for the first time that DER blocked the TPA stimulation of ERK activity and suggested that the inhibition of TPA-induced AP-1 activity by DER is likely through inhibition of ERK but not JNK or p38 kinase pathway.

Temporal processing ability in above average and average readers

In the present study, we compared the rapid visual and auditory temporal processing ability of above average and average readers. One hundred five undergraduates participated in various visual and auditory temporal tasks. The above average readers exhibited lower auditory and visual temporal resolution thresholds than did the average readers, but only the differences in the auditory tasks were statistically significant, especially when nonverbal IQ was controlled for. Furthermore, both the correlation and stepwise multiple regression analyses revealed a relationship between the auditory measures and the wide range achievement test (WRAT) reading measure and a relationship between the auditory measures and a low spatial frequency visual measure and the WRAT spelling measure. Discriminant analysis showed that together both the visual and auditory measures correctly classified 75% of the subjects into above average and average reading groups, respectively. The results suggest that differences in temporal processing ability in relation to differences in reading proficiency are not confined to the comparison between poor and normal readers.

Testbed for a scalable terabit optical local area network

The design of a fiber-optic local area network (LAN) demonstration system is described. A complete LAN system would consist of an array of 16 personal computers (PC's), where each PC has a network interface card (NIC) with a parallel fiber-optic datalink to a centralized optoelectronic switch core. The centralized core switches the data generated by 16 NIC's, up to 128 Gbit/s of bandwidth. The demonstrator is designed to scale to terabits of bandwidth by use of an emerging optoelectronic technology, i.e., integrated complementary metal-oxide semiconductor (CMOS) substrates with vertical-cavity surface-emitting laser (VCSEL) and photodetector optical input and output. A subset of the complete system was constructed and is operational. A prototype NIC card, with Motorola Optobus VCSEL transceivers for the optical datalinks, was constructed and is described. A prototype high-speed bipolar switch core, with statically configurable electrical positive-emitter coupled-logic 16 x 16 crossbar switches, CMOS field-programmable gate arrays, and Motorola Optobus transceivers, was constructed and is described. We successfully demonstrated the transmission of high-speed packetized data from one NIC card, through 10 m of parallel fiber ribbon and the centralized switch core, and back to the NIC. We summarize our experiences on the design and testing of our first demonstration system and our development toward a terabit switch core.