bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4734: Validation of genome-wide colorectal cancer genetic risk factors in African- and European-Americans
Authors: Kupfer Sonia , Anderson Jeffrey , Hooker Stanley , Henderson Cory , Kittles Rick , Kim Karen , Keku Temitope , Sandler Robert S. , Ellis Nathan A.
Published: February 2011

Background: Genome-wide association studies have identified several colorectal cancer (CRC) genetic risk factors. However, these studies have been performed primarily in individuals of European descent and none include African Americans (AAs). Determining CRC genetic risk factors in AAs is important because CRC incidence and mortality rates are highest of all US populations.

Aim: To validate genome-wide CRC genetic risk factors, we tested single nucleotide polymorphism (SNP) associations in ten chromosome (chr) regions in AAs and European-Americans (EAs).

Methods: We genotyped 22 SNPs in 1725 AA and 883 EA CRC cases and controls using Sequenom iPLEX. Ancestry estimates were obtained using STRUCTURE 2.1. We tested for allelic association and calculated odds ratios and confidence intervals using logistic regression adjusting for ancestry, age and gender.

Results: Association results are shown in the Table. In AAs, rs10795668 (chr 10) and rs10318 (chr 15) were significantly associated with CRC. rs7014346 (chr 8) and rs355527 (chr 20) trended toward significant associations. In EAs, three SNPs on chr 8 were significantly associated with CRC. In addition, two chr 11 SNPs (rs3802842 & rs1074997) and rs1862748 (chr 16) were significantly associated with disease in EAs. SNPs on chr 15 and chr 16 are located in or near genes GREM1 and CDH1 respectively. SNPs on chr 8, 10, 11 and 20 are in gene deserts.

Conclusion: This is the first study to validate genome-wide SNP associations in AAs. We also confirm several associations in EAs. SNPs on chr 15 & 16 are located in genes involved in TGFβ signaling (GREM1 & CDH1) which has been implicated in CRC pathogenesis, while those on chr 8, 10, 11 and 20 are in gene deserts. Future fine-mapping in these regions is warranted to identify functional variants.Genome-wide SNP associations in African- and European-AmericansChr (gene)SNPReference alleleAllele frequency casesAllele frequency controlsOR [95% CI]p*African Americans      8rs7014346A0.420.391.14 [0.99-1.31]0.0710rs10795668A0.080.061.41 [1.07-1.87]0.0415 (GREM1)rs10318T0.050.031.45 [1.02-2.05]0.0520rs355527A0.180.200.87 [0.73-1.04]0.09European Americans      8rs6983626T0.120.091.38 [1.00-1.91]0.058rs6983267G0.520.471.24 [1.01-1.51]0.048rs7837328A0.430.371.30 [1.06-1.60]0.0111rs3802842C0.330.281.26 [1.02-1.57]0.0211rs10749971G0.410.331.42 [1.15-1.74]0.000216 (CDH1)rs1862748T0.280.320.80 [0.64-0.99]0.04

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4734.
Abstract 4735: Examining known diabetes risk variants for association with prostate cancer in a multiethnic population
Authors: Waters Kevin M. , Stram Daniel O. , Cheng Iona , Schumacher Frederick R. , Wilkens Lynne R. , Monroe Kristine R. , Kolonel Laurence N. , Henderson Brian E. , Marchand Loïc Le , Haiman Christopher A.
Published: February 2011

Epidemiologic studies have found evidence of an inverse association between diabetes status and prostate cancer risk. Recently genome-wide association studies of these two diseases have identified a single risk allele at the HNF1B locus that is associated with both diseases along with two risk loci (JAZF1 and THADA) that have been associated with both diseases through distinct unlinked variants. We, as part of the Population Architecture using Genomics and Epidemiology (PAGE) Study, explored the hypothesis that common genetic variation may explain, in part, the inverse association between type II diabetes and prostate cancer, by examining known diabetes risk variants for their association with prostate cancer. Our study consists of men from a prostate cancer case-control set of 2,707 cases and 2,438 controls from five racial-ethnic groups (African American, European American, Latino, Japanese American, and Native Hawaiian) of the Multiethnic Cohort. The allelic discrimination assay was used to genotype 21 diabetes risk variants from 18 loci identified by genome-wide association studies. Unconditional logistic regression was used to examine these alleles for association with prostate cancer risk. In ethnic-pooled analysis, we did not find evidence of an association with prostate cancer for the diabetes risk alleles in either of the two loci previously associated with prostate cancer (JAZF1, rs864745, OR 1.01, 95% CI 0.92-1.10; THADA, rs7578597, OR 1.11, 95% CI 0.97-1.27). An allele (rs7961581) in the TSPAN8 locus, which has been shown to be positively associated with diabetes risk had a protective association with prostate cancer at a nominally statistically significant level (OR 0.88, 95% CI 0.80-0.97, p=7.8×10-3). Except for the risk allele at HNF1B (allele G of rs4430796), which we previously reported to be associated inversely with prostate cancer, we found no evidence of an association with prostate cancer for the diabetes risk loci at JAZF1 and THADA despite other independent alleles at these loci being associated with prostate cancer. In summary, we found an association between the TSPAN8 allele and prostate cancer risk that needs to be replicated in larger populations. Resequencing and fine-mapping studies to identify causal alleles in large association studies will be important in exploring the role of common risk variants in the inverse association between diabetes and prostate cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4735.
Abstract 4739: Interactions between variants of angiogenesis pathway genes and reflux symptom, BMI, and smoking in esophageal adenocarcinoma susceptibility
Authors: Zhai Rihong , Chen Feng , Liu Geoffrey , Ter-Minassian Monica , Su Li , Asomaning Kofi , Wang Zhaoxi , Kulke Matthew H. , Lin Xihong , Heist Rebecca S. , Sheu Chau-Chyun , Wain John C. , Hooshmand Susanne H. , Nishioka Norman S. , Christiani David C.
Published: February 2011

Esophageal adenocarcinoma (EA) is a complex malignancy that involves multiple genetic and environmental risk factors. Genetic polymorphisms in angiogenesis pathway, gastroesophageal reflux symptoms (reflux), higher body mass index (BMI), and tobacco smoking have been individually associated with EA development. However, interactions among multiple factors in EA risk have not been well characterized. We conducted a case-only study to investigate gene-environment interactions among 145 functional/tagging SNPs of angiogenesis pathway genes, reflux, smoking, and BMI in 335 patients with EA. We used a two-stage approach to detect interactions: first, we applied random forest (RF) approach to select important interacting markers based on mean decrease in accuracy and mean decrease in GINI index; then we estimated the interaction odds ratios (ORinter) of RF selected interaction markers by case-only logistic regression, adjusting for covariates and false discovery rate (FDR). We identified twelve interaction markers that were significantly associated with EA risk (all FDR_Ps<0.05). Among them, six interaction markers, including reflux*rs2295778 (HIF1AN) (ORinter=2.27; 95% CI, 1.44-3.57), reflux*rs996999 (MMP1) (ORinter=1.80; 95%CI, 1.12-2.89), reflux*rs13337626 (TSC2) (ORinter=2.18; 95%CI, 1.15-4.12), BMI*rs2114039 (PDGFRA) (ORinter=2.06; 95%CI, 1.29-3.30), BMI*rs6554164 (PDGFRA) (ORinter=1.92; 95% CI, 1.20-3.08), and BMI*rs17708574 (PDGFRB) (ORinter=1.89; 95%CI, 1.12-3.18) were significantly associated with increased risk of EA. On the other hand, six interaction markers, including reflux*rs2519757 (TSC1) (ORinter=0.43; 95% CI, 0.21-0.83), smoking*rs2295778 (HIF1AN) (ORinter=0.45; 95%CI, 0.26-0.79), smoking*rs2296188 (FLT1) (ORinter=0.50; 95%CI, 0.28-0.87), BMI*rs2296188 (FLT1) (ORinter=0.41; 95%CI, 0.24-0.73), BMI*rs11941492 (KDR) (ORinter=0.52; 95%CI, 0.32-0.85), and BMI*rs17619601 (FLT1) (ORinter=0.26; 95%CI, 0.09-0.75) were significantly associated with decreased risk of EA. These findings suggest that variants in angiogenesis pathway genes, reflux, smoking, and BMI jointly contribute to EA development through gene-environment interactions.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4739.
Abstract 4743: Genome-wide gene-centric discovery of disease variants in neuroblastoma
Authors: Nguyen Le B. , Diskin Sharon , Hakonarson Hakon , Maris John M. , Li Hongzhe
Published: February 2011

Genome-wide associations studies (GWAS) have been increasingly utilized to identify novel genetic variants for complex human diseases. As we are interested in disease causal variants that have a high likelihood of impacting protein encoding genes, we developed a gene-centric genome-wide association approach. This method computes the aggregated effect of all SNPs mapped on a gene normalized by the number of SNPs on this gene. Therefore, this method is able to identify genes whose SNPs have marginal effect size by conventional statistical methods because the Bonferroni correction criteria are relaxed since the number of genes in the human genome is far less than the number of SNPs on the array. We applied this gene-centric method to both high-risk and low-risk neuroblastoma, a cancer of early childhood with less than 40% cure rate in high-risk patients and more than 95% survival rate in low-risk patients. We utilized a discovery set of 1627 cases and 2575 control subjects, and an independent replication set with 398 cases and 1507 control subjects. First, we provided proof of concept by replicating each prior association study result reported by our lab, including the hypothetical gene FLJ44180 at chromosome band 6p22, BARD1 at 2q35 and LMO1 at 11p15 (P=9.92×10−11, <1.00×10−30, and 1.80 ×10−7, respectively). Additionally, we also discovered two new association signals that robustly replicated in low-risk cases only: DUSP12 at 1q23 (P=3.03 ×10−6) and DDX4 at 5q11 (P=2.39×10−6). These data suggest that a gene-centric statistical approach to GWAS data can identify causal variants in relatively rare phenotypic subsets.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4743.
Abstract 4761: The iCD40. MyD88 combo-vector: A new platform for enhanced DC tumor immunotherapy
Authors: Narayanan Priyadharshini , Lapteva Natalia , Kemnade Jan O. , Slawin Kevin M. , Spencer David M.
Published: February 2011

Introduction: Given the pre-eminent role of dendritic cells (DCs) as antigen-presenting cells, their exploitation as natural adjuvants in vaccination protocols for the treatment of various malignancies and infectious diseases is not surprising. Nevertheless, inadequate or unsustained activation has likely limited response rates in clinical trials. We previously reported a potent synthetic dimerizer drug-inducible CD40 (iCD40) receptor that permits temporally controlled DC-specific activation within the context of an immunological synapse (Hanks et al, Nat Med, 2005). We showed that when combined with Toll-like Receptor (TLR) adjuvants, iCD40-modified DCs (iCD40-DCs) have enhanced survival, co-stimulatory marker expression, migration, IL-12 production, antigen (Ag)-specific T cell stimulatory capacity and anti-tumor responses (Lapteva et al, Cancer Res, 2007). A phase I/II clinical trial based on iCD40-DCs to treat castration-resistant, metastatic prostate cancer began enrolling patients in August 2009.

Procedures: To simplify this approach, we have developed a unified, inducible DC switch, called “iCD40. MyD88”, which combines signaling elements from costimulatory molecule, CD40, and TLR adapter, MyD88, fused to tandem FK506-binding binding proteins (FKBP12v36). Activation is initiated in vitro or in vivo by lipid-permeable dimerizing ligands (i.e. AP1903 or AP20187).

Results: Both murine and human iCD40. MyD88-DCs secrete high (ng) levels of IL-12 and maturation markers in a ligand-dependent fashion without the need for exogenous adjuvants. iCD40. MyD88 activation is associated with synergistic activation of IKKα/β and p38. Moreover, tumor-bearing mice treated with antigen-pulsed, iCD40. MyD88-DCs show a potent anti-tumor immune response, consistent with expansion of antigen-specific CTLs in vivo. Bicistronic vectors combining iCD40. MyD88 along with tumor-associated antigens are underway.

Conclusion: This “combo-switch” permits potent, targeted activation of antigen-pulsed DCs in vivo, leading to improved anti-tumor immunity with a high likelihood for reduced side effects. Production of a single vector that combines a potent DC switch with tumor antigen is the first requisite step leading to economically viable, “off-the-shelf”, vaccine therapies for cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4761.
Abstract 4762: Dendritic cell therapy delays disease progression in hepatocellular carcinoma
Authors: Khan Jamal A. , Yaqin Sharmin B.
Published: February 2011

Hepatocellular carcinoma(HCC) has a poor outcome with all known conventional treatment plans. In advanced stage disease, surgery and ablation are also not done. In such situations, patients look for alternative therapies and accept them without even oncologists opinion. Dendritic cell therapy is one of the options in such cancers and HCC is said to be immunoresponsive. We have treated 12 patients of advanced stage HCC in our center with this approach. Patients were informed about the experimental nature of the protocol and gave their written consent. The protocol was isolation of peripheral blood mononuclear cells from about 25 ml of patient's blood and culture them in RPMI-1640, GM-CSF and IL-4. After 6 days of culture, immature dendritic cells were exposed to Tumor Associated Antigen(TAA) and cultured for additional 2 days. The final product was evaluated by immunocytochemistry (CD83/86+ve) and confirmed free of microbial and mycoplasma contamination. It is administered to the same patient by mixing it in 100 ml of dextrose-normal saline. The adverse effects observed were fever, fever with shivering and rigors and lethargy for a day or two. No patient required hospitalization during treatment. The process is repeated by taking fresh blood sample every 23 days and is continued till the patient kept showing clinical benefits. 5 patients have shown radiological stabilization of disease for more than 2 years including improvement in performance status from 3/2 to 1 (ECOG scale). 3 patients showed no response and 4 patients showed partial response with mean survival of 7 months. We conclude that early stage patients of HCC should be given an option of dendritic cell therapy after completion of their primary conventional treatment plan.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4762.
Abstract 4765: Treatment with anti - IL 17 A coupled with COX-2 inhibitor significantly decreases breast cancer associated secondary metastasis in a model of autoimmune arthritis
Authors: Roy Lopamudra Das , Schettini Jorge L. , Gruber Helen E. , Sahraei Mahnaz M. , Mukherjee Pinku
Published: February 2011

Introduction: Inflammation is a critical hallmark of autoimmune arthritis (AA) and cancer. We have previously shown that the site of chronic inflammation linked to AA creates a milieu that attracts tumor cells to home and grow in the inflamed bones and lungs which are frequent sites of breast cancer metastasis. We have identified IL-17, a critical pro-inflammatory cytokine involved in osteoclastic bone resorption in AA as the underlying mechanism for increased metastasis. In addition, high levels of cyclooxygenase 2 (COX-2) is linked to both AA and breast cancer metastasis. We report that blocking the IL-17 and COX-2 pathways simultaneously significantly reduces the development of breast cancer associated metastasis in a spontaneous model of AA.

Methods: 4T1 mammary gland tumors were generated in mice genetically prone to develop AA (designated SKG mice). When tumors reached > 0.2 gms, anti-IL17 antibody treatment was injected intraperitoneally once a week for three weeks. Celecoxib, a specific COX-2 inhibitor was orally administered starting at the same time as the anti-IL-17 antibody but was given daily until sacrifice. One week after the last injection, mice were sacrificed. Secondary metastasis and the associated inflammatory milieu were evaluated.

Summary of Results: Data demonstrated that compared to the untreated mice or mice treated with isotype control antibody, survival was significantly enhanced and primary tumor burden was significantly decreased in the anti-IL-17+celecoxib treated mice. Importantly, we observed significant decrease in lung and bone metastasis as compared to the control group. The contributing factor was recognized to be the low neutrophilic and granulocytic infiltration and therefore low inflammation in the lungs as well as reduced severity of arthritis with low cellular infiltration and low osteoclast formation in the bones of mice treated with anti-IL-17+celecoxib.

Conclusion: We report that treatment with anti-IL 17 and celecoxib significantly reduced primary tumor burden, reduced metastasis to the lungs and bones, and increased survival in SKG mice.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4765.
Abstract 4766: Multivalent VRP-based anti-tumor immunotherapy is an effective therapeutic strategy in a rat model of breast cancer
Authors: Laust Amanda K. , Mkrtichyan Mikayel , Davtyan Hayk , Khlgatyan Jivan , Ghochikyan Anahit , Liu Han , Agadjanyan Michael G. , Nelson Edward L.
Published: February 2011

It is widely accepted that the genetic instability of a tumor results in both intra- and inter-tumoral genetic heterogeneity, which leads to heterogeneous tumor-associated antigen (TAA) expression and contributes to the outgrowth of antigen-loss variants in response to immunologic selective pressure. Using a rat neu encoding, alphavirus based virus-like replicon particle (VRP) with restricted in vivo tropism for dendritic cells in a fully tolerant Fisher 344 rat mammary tumor (13762 MAT B III) model, we previously demonstrated the ability to cure a modest proportion, 20-40%, of rats with pre-existing mammary tumors and observed the outgrowth of antigen loss variant tumors in a proportion of animals that ultimately succumbed to their tumor. Thus, we hypothesized that strategies targeting multiple tumor antigens would lead to improved treatment efficacy. Expression of the cancer testes antigen, Brother of Regulator of Imprinted Sites (BORIS) was confirmed in the 13762 MAT B III tumor. Rats with pre-existing tumors were treated with VRP encoding either the TAA rat neu or the BORIS target antigen, alone or in combination. We found that targeting either rat neu or BORIS alone was effective in treating a proportion of animals. Interestingly, administration of both VRP agents at a single anatomic site drastically decreased the treatment efficacy, by approximately 50%, while separating their administration into two separate anatomic sites enhanced the treatment efficacy over that provided by each agent alone, to >56% cure rate. Herein, we will present data addressing potential mechanisms for these treatment observations. To our knowledge, this is the first report of multivalent anti-tumor immunotherapy utilizing solely the VRP vector system. These data represent an exceptionally promising platform upon which to build more efficacious immunotherapeutic strategies including those targeting multiple defined TAAs.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4766.
Abstract 4801: Hypomethylation of a LINE-1 promoter activates an alternate transcript of the MET oncogene in bladders with cancer
Authors: Liang Gangning , Wolff Erika M. , Han Han F. , Byun Hyany-Min , Sharma Shikhar , Nichols Peter , Siegmund Kimberly D. , Jones Peter A.
Published: February 2011

Background: It was recently shown that a large portion of the human transcriptome can originate from within repetitive elements, leading to ectopic expression of protein-coding genes. However the mechanism of transcriptional activation of repetitive elements has not been definitively elucidated.

Principal findings: For the first time, we directly demonstrate that hypomethylation of retrotransposons causes altered gene expression in humans. We also reveal that active LINE-1s switch from a tetranucleosome to dinucleosome structure, acquiring H2A.Z and nucleosome free regions upstream of TSSs, previously shown only at active single copy genes. Hypomethylation of a specific LINE-1 promoter was also found to induce an alternate transcript of the MET oncogene in bladder tumors and across the entire urothelium of tumor-bearing bladders.

Conclusions: These data show that, in addition to contributing to chromosomal instability, hypomethylation of LINE-1s can alter the functional transcriptome and plays a role not only in human disease but also in disease predisposition.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4801.
Abstract 4806: Breast carcinoma DNA methylation profiles are associated with tumor size, alcohol intake, and folate intake
Authors: Christensen Brock C. , Kelsey Karl T. , Houseman E. Andres , Marsit Carmen J. , Zheng Shichun , Wrensch Margaret R. , Wiemels Joseph L. , Nelson Heather H. , Karagas Margaret R. , Kushi Lawrence H. , Kwan Marilyn L. , Wiencke John K.
Published: February 2011

The cornerstones of breast cancer prognosis and management are tumor size and axillary lymph node involvement. We investigated both individual genes and overall patterns of methylation in relation to these and other tumor characteristic along with environmental exposure variables. The Illumina GoldenGate methylation bead-array platform was used to measure 1413 autosomal CpG loci associated with 773 cancer-related genes in 162 FFPE primary breast tumors (AJCC stage I-IV) from the Pathways Study. From CpG locus-by-locus tests, the strongest methylation associations (based on the number of CpG loci with Q-values < 0.05) were for tumor grade (209 loci), tumor size (74 loci), estrogen receptor status (183 loci), progesterone receptor status (69 loci), and triple negative status (130 loci). Unsupervised clustering, using a recursively partitioned mixture model (RPMM), of all autosomal CpG loci across all tumors resulted in eight distinct methylation profile classes, and class membership was significantly associated with patient race (P < 0.02) and tumor size (P < 0.001). Using multinomial logistic regression to adjust for potential confounders, patient age, alcohol intake, total dietary folic acid intake, and tumor size were all significantly associated with tumor methylation profile (all P < 0.0001). Furthermore, there were opposite trends of methylation for increasing alcohol and folate intake, which were associated with decreased and increased methylation, respectively. Lymph node status, tumor grade, estrogen receptor status and tumor histology were not associated with methylation class in the multinomial model. In an RPMM of tumors from postmenopausal patients only, methylation class membership was significantly associated with estrogen receptor status (P < 0.03). Selected CpG loci were validated with Sequenom EpiTYPER methylation analysis and methylation of several candidate genes were associated with silencing of gene expression. Taken together, these data demonstrate strong associations between both specific gene methylation and overall DNA methylation profiles and tumor characteristic and patient exposure history.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4806.
Abstract 4808: SIAH2-dependent proteolysis in cell migration, tumor growth, and cancer metastasis
Authors: Liao Yang , Schmidt Rebecca R. , Walton Zandra , Tang Amy H.
Published: February 2011

The dismal prognosis of patients diagnosed with invasive and metastatic cancer points to our limited arsenal of effective anticancer therapies. The central importance of EGFR/HER2/RAS pathway activation has been well established in neoplastic transformation and tumorigenesis. An important goal in cancer biology is to identify novel and effective means to inhibit activated EGFR/HER2/K-RAS signals and reverse malignant transformation, tumor growth and cancer metastasis. SIAHs are the human homologs of Drosophila Seven-In-Absentia (SINA), an evolutionarily conserved RING E3 ligase that is an essential downstream signaling module and critical “gatekeeper” required for RAS signal transduction in human cancer cells. By targeting the most downstream signaling module identified in the RAS pathway - the SIAH2 proteolytic machinery, we are able to block tumorigenesis and metastasis in multiple of the most aggressive forms of human cancer cells known in athymic nude mice. Although we are fully cognizant of the systemic limitation in the xenograft models and incomplete mimicry of the full-spectrum metastatic processes observed in athymic nude mice, we are encouraged by the impressive anti-SIAH2-based tumor suppression in these preclinical studies. In this study, we aim to identify the molecular mechanism(s) of SIAH2 action in human cancer cells. To delineate SIAH2 function in cancer, through a proteomic approach, we identified three endogenous LIM domain proteins, TRIP6/FHL2/LPXN, as the bona fide SIAH2-interacting proteins isolated from the most aggressive human cancer cell lines (A549, MiaPaCa and MDA-MB-435 cells) in parallel. We provide extensive biochemical evidence to show that TRIP6/FHL2/LPXN are bona fide SIAH2 substrates. These new SIAH2 substrates can successfully rescue cell motility and viability defects observed in SIAH2-deficient cancer cells, suggesting that these focal adhesion proteins may represent one of many diverse signaling modules that function downstream of SIAH2 in mediating aspects of RAS-dependent signaling in normal development and cancer. Our results suggest In response to ERBB/RAS activation, SIAH2 E3 ligase modulates cell junction, adhesion and migration by targeting focal adhesion proteins for ubiquitin-mediated proteolysis to promote cell migration, tumorigenesis and metastasis in human cancer cells. The identification of SIAH2-mediated focal adhesion and cell junction modulation may have important implications in cancer biology to explain the well-documented modulations in focal adhesion, cell junction and motility in response to ERBB/RAS activation in human cancer cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4808.
Abstract 482: The HER-2 erbB receptor is vital for growth of breast cancer cells in bone
Authors: Dawsey Scott J. , Ignatoski Kathleen M. Woods , Day Kathleen C.
Published: February 2011

HER-2 is a receptor tyrosine kinase that has been shown to be over expressed in 30% of human primary breast cancers (BrCa). Our animal model data and human bone met data, which we present here, indicates that HER-2 up-regulation is required for breast cancer cells to grow in and remodel bone. However, most bone metastases from BrCa will arise from a primary diagnosis of ER positive/HER-2 negative disease. We found that MCF-7 cells, an ER positive/HER-2 negative breast cancer model, formed tumors in bone that had up-regulated HER-2 protein expression. In order to directly test whether or not HER-2 expression has an affect on bone metastasis, we engineered a knock down of the HER-2 receptor in MCF-7 cells by utilizing a lentivirus plasmid containing the shRNA to the HER-2 receptor. Both the shRNA HER-2 knock-down and the vector-only control expressed the Green Fluorescence Protein (GFP) and puromycin resistance for plasmid selection. Our engineered MCF-7 control cells (shVector alone) or the HER-2 knock-down (shHER-2) were injected into the tibia of SCID mice. We found that both the vector-only and HER-2 knock-down cells grew tumors in mouse tibia. Anti-HER-2 immunohistochemical (IHC) analysis showed that the HER-2 protein was re-expressed in the knock down cells in tumors formed in tibiae. Additionally, we found that in eight patients with breast cancer bone metastasis, 100% of these cases contained a significant expression of HER-2 positive cells by IHC. As confirmation of our mouse studies, we found that all of the human bone biopsies obtained from ER positive/HER-2 negative disease were up-regulated for HER-2 in the bone microenvironment. Concomitant with our human data, MCF-7 cells required exogenous estrogen to form tumors in mammary fat pads and did not require exogenous estrogen to form tumors in bone. Therefore, we believe that BrCa cells can change, up-regulate protein expression of HER-2, and become estrogen independent in the bone microenvironment. It may be that these women could benefit from intervention with agents against HER-2.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 482.
Abstract 4825: Serum selenium concentration and risk of colorectal cancer in postmenopausal women: The Women's Health Initiative Observational Study
Authors: Takata Yumie , King Irena B. , Song Xiaoling , Diamond Alan M. , Foster Charles B. , Hutter Carolyn M. , Hsu Li , Duggan David J. , Langer Robert D. , Petrovitch Helen , Shikany James M. , Vaughan Thomas L. , Kristal Alan R. , Lampe Johanna W. , Prentice Ross L. , Peters Ulrike
Published: February 2011

In vitro and animal experimental studies have reported beneficial effects of selenium on colorectal cancer (CRC), yet results from epidemiological studies are inconsistent. Few of these studies have examined CRC risk among women, and none have been sufficiently large to examine risk in subgroups. This study investigated whether baseline serum selenium concentration was associated with subsequent CRC risk among postmenopausal women in a case-control study nested within the Women's Health Initiative Observational Study. We included 804 CRC cases diagnosed between October 1993 and September 2005 and 804 controls matched to cases on age, enrollment date, clinical center, race/ethnicity, hysterectomy status, and prevalent condition at baseline. Baseline serum selenium concentration was measured by atomic absorption spectrometry. Multivariate logistic regression was used to estimate the odds ratios (OR) and 95% confidence intervals (95% CI) associated with increasing serum selenium concentrations. The corresponding median selenium concentrations in the 1st to 5th quintiles were 110.5, 123.2, 133.5, 144.8, and 162.2 µg/l (range: 81.03 - 398.70 µg/l). The selenium concentration was weakly and positively associated with the risk of CRC (ptrend = 0.08); the adjusted ORs (95% CIs) for the risk of CRC comparing the 2nd, 3rd, 4th, and 5th quintile of serum selenium concentrations with the 1st quintile were 1.14 (0.83-1.58), 1.16 (0.84-1.60), 1.36 (0.99-1.87) and 1.27 (0.92-1.76). The trend was somewhat stronger for past and current smokers [OR (95% CI) for the 5th vs. 1st quintile = 1.38 (0.89-2.13), ptrend = 0.13] than never smokers [OR (95% CI) for the 5th vs. 1st quintile = 1.16 (0.72-1.87), ptrend = 0.48]. However, the difference was not statistically significant (pinteraction = 0.53). Findings from this large study with relatively high serum selenium concentrations suggest no beneficial effect of selenium on colorectal cancer among women, which is consistent with results of previous smaller observational studies.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4825.
Abstract 4847: Arginine deprivation by PEG-ADI induces autophagic cell death and enhances the tumor suppression effect of gemcitabine in pancreatic cancer
Authors: Daylami Rouzbeh , Muilenburg Diego , Bowles Tawnya L. , Martinez Steve R. , Bold Richard J.
Published: February 2011

Metabolic stress has been recently recognized to induce autophagic cell death; we have recently shown that nearly 80% of pancreatic adenocarcinoma tumor specimens are auxotrophic for the semi-essential amino acid arginine due to transcriptional suppression of argininosuccinate synthase (ASS). We hypothesized that selective arginine deprivation would induce autophagy and furthermore, by targeting alternative death pathways would increase the cytotoxic response to the chemotherapy gemcitabine.

Methods: The human pancreatic cell line MIA-PaCa-2 was shown to be deficient in ASS by western blot. Arginine deprivation was achieved by treatment of cells and xenografts with PEG-ADI, which shuttles arginine to citrulline. Cells were treated with either PEG-ADI, gemcitabine or both. Cell death was measured by MTT and FACS. Western blot was used to measure autophagy by LC3 processing and apoptosis by caspase-3 cleavage. RRM2 expression was measured by western blot in cells treated with PEG-ADI. ASS expression was measured by western blot in cells treated with gemcitabine. To test the in vivo effect arginine deprivation a mice xenograft model was created by subcutaneously injecting Mia-PaCa2 cells into the flanks of 28 mice (two tumors per mice). Tumors were allowed to mature at which time the mice were assigned to one of four treatment groups: PBS control (once weekly), ADI-PEG20 (5 IU once weekly), Gemcitabine (125mg/kg twice weekly), or Gemcitabine and ADI-PEG20. All treatments were administered via intraperitoneal injection and tumors were measured twice a week.

Results: 1. MIA-PaCa-2 lacks ASS and is auxotrophic for arginine. 2. PEG-ADI induces autophagy and cell death 3. Gemcitabine has little in vitro cytotoxicity 4. The combination of gemcitabine and PEG-ADI is at least additive in vitro and in vivo. 5. PEG-ADI does not regulate RRM2 expression and gemcitabine does not regulate ASS expression.

Conclusions: Therapy targeting autophagy may provide increased efficacy for traditional genotoxic chemotherapies in pancreatic cancer. PEG-ADI in combination with gemcitabine is a novel combination to be pursued in clinical trials

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4847.
Abstract 4849: Role of autophagy in breast cancer metastasis and treatment
Authors: Maycotte Paola , Thorburn Jackie , Thorburn Andrew
Published: February 2011

Autophagy has shown to be important for tissue homeostasis and many human diseases as well as cancer. However, in cancer its role is controversial because autophagy may both promote and inhibit tumor development and progression. In cancer treatment, autophagy may control the likelihood with which tumor cells die but for different treatments and different tumors these effects may be opposite.

Breast cancer is the most common type of cancer in women in the US; and, although it is not yet clear how should we manipulate autophagy in people with cancer, autophagy is already being manipulated in breast cancer patients in clinical trials. Moreover, because most anti-cancer treatments induce autophagy, we may also be inadvertently manipulating autophagy in the majority of breast cancer patients.

To evaluate if autophagy is important in breast cancer progression and treatment, we used murine 4T1 cells, a model of metastatic breast cancer. Using matched tumor cells with different metastatic potential we found that basal autophagy was increased with increasing metastasis implying that autophagy is required to allow metastatic progression. To test if treatments that are used for metastatic breast cancer were affected by autophagy, we examined LC3 processing after 4T1 cell treatment with common breast cancer treatments including etoposide, cisplatin, doxorubicin and cyclophosphamide. In all cases, these drugs increased autophagy; however, although autophagy inhibition with chloroquine treatment increased cell death in clonogenic assays, Atg12 knockdown in 4T1 cells had no effect on either long or short term viability assays after treatment with the four chemotherapeutic drugs. Thus, we hypothesize that inhibition of specific steps in the autophagic pathway might have different effects on cell viability after treatment. Further testing of this hypothesis will be discussed.

Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4849.
Abstract 4850: Tumor mitochondria contribute to autophagic properties of the cancer cells
Authors: Tu Yi-Fang , Ma Yewei , Wong Lee-Jun C.
Published: February 2011

Autophagy is a cellular housekeeping process that removes damaged or unwanted cellular components and recycles them to build new constituents. It is essential for tumor growth under adverse environment. Mitochondria play an important role in the formation of autophagosome and its subsequent docking and fusion with lysosome. In order to study the contribution of mitochondria to the regulation of homeostatic autophagy in cancer cells, we used a transmitochondrial cytoplasmic hybrid (cybrid) system to investigate the role of tumor-derived mitochondria in a defined nuclear background. Since LC3-II is the autophagosomal membrane-bound form of microtubule-associated protein 1 light chain 3 (LC3-I), increased LC3-II or increased LC3-II/LC3-I ratio is an indication of activation of autophagy. Cybrids containing mitochondria derived from a highly metastatic breast cancer cell line MDA-MB-231 (c231) exhibited lower LC-II levels but higher ratio of LC3-II/LC-I than other cybrids containing mitochondria derived from low or moderate metastatic breast cancer cell lines MDA-MB-436 and MDA-MB-468, as well as mammary epithelial cell MCF-10A (c10A). Increase of LC3 puncta on immunofluorescence stain and decrease of sequestosome 1 (p62/SQSTM1), a marker of autophagic flux, in c231 cells, compared to other cybrids, further indicated that mitochondria derived from high metastatic breast cancer cell line MDA-MB-231 could increase autophagy and accelerate autophagic flux. The accelerated autophagic flux in c231 cells can be blocked by the autophagy inhibitor bafilomycin-A1. In addition, the mitochondria in c231 cells were noted to promote mitochondrial permeability transition (MPT) and were surrounded by LC3 puncta. These results suggested that tumor mitochondria from highly metastatic breast cancer cell line, MDA-MB-231, can promote homeostatic autophagy of cancer.

Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4850.
Abstract 4854: Inhibition of high-mobility group box 1 protein (HMGB1) release sensitizes cancer cells to chemotherapy
Authors: Tang Daolin , Kang Rui , Zeh Herbert J. , Lotze Michael T.
Published: February 2011

Metabolic and therapeutic stress can simultaneously provoke both adaptive and apoptotic responses in cancer cells. The sum of these programmed signals determines the fate of the cell: cell death or cell survival. As the catalogue of defects in pathways that control apoptosis in human tumors is expanding, understanding the significance of the alternative stress fate, autophagy, has become increasingly important. High-mobility group box 1 protein (HMGB1) is a highly conserved nuclear protein, acting as an architectural chromatin-binding factor that bends DNA and promotes protein assembly on specific DNA targets. In addition to its intranuclear roles, HMGB1 was also discovered recently to function as an extracellular signaling molecule during inflammation, cell differentiation, cell migration, and tumor metastasis. Ethyl pyruvate was first identified as an experimental agent that ameliorated inflammation, significantly reducing circulating levels of HMGB1 in animals with sepsis. Similarly, glycyrrhizin was identified as a direct small-molecule inhibitor of HMGB1 release and activity. To determine whether inhibition of HMGB1 release sensitizes cancer cells to chemotherapy, we pretreated cell with ethyl pyruvate or glycyrrhizin. These inhibitors attenuated melphalan-induced HMGB1 release. Moreover, inhibition of HMGB1 decreased autophagy by microtubule-associated protein 1 light chain 3 (LC3) puncta and LC3-II/p62 levels assay, and increased apoptosis by flow cytometry and cleaved-poly (ADP-ribose) polymerase (PARP) assays in Panc2.03 and HCT116 tumor cells when treated with chemotherapy. To further characterize the role of HMGB1 release in cancer cells following chemotherapy, a target-specific short hairpin RNA (shRNA) to HMGB1 was transferred into Panc2.03 and HCT116 tumor cells. Transfection of HMGB1-shRNA led to a significant decrease in HMGB1 protein as well as release in these cells. Depletion of HMGB1 by shRNA in these cells decreased autophagy and rendered them significantly more sensitive to melphalan-induced apoptotic cell death. Thust HMGB1 release links autophagy and apoptosis, and serves as a potential drug target for therapeutic intervention.

Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4854.
Abstract 4857: The role of autophagy in taxane resistant breast cancer models
Authors: Rechache Nesrin S. , Riggins Rebecca B. , Shajahan Ayesha N. , Zwart Alan , Clarke Robert
Published: February 2011

Treatment with the taxanes (Paclitaxel or Docetaxel) is often the therapy of choice for women with advanced breast cancer. In most cases, the taxanes can arrest cell proliferation at the G2/M phase and cause cell death. However, some tumors develop resistance during the course of treatment, which is a major concern for both patients and physicians. Several mechanisms have been proposed to explain how resistance to the taxanes occurs, but this phenomenon remains incompletely understood. We hypothesize that changes in cell death signaling, through apoptotic and non-apoptotic pathways, are responsible for taxane resistance in breast cancer. Using the MDA-MB-231 breast cancer cell line model, we selected cells that are resistant to either Docetaxel (DocR) or Paclitaxel (PacR). Subsequently we studied levels of cell death and the response to IC50 concentrations of these drugs. Given the molecular crosstalk that can occur between cells dying by apoptosis and the autophagy process, Western blots for prosurvival Bcl-2 and NFκB were performed, and these showed reduced expression in the taxane resistant cells compared to the sensitive cell lines. In conjunction with changes in apoptotic markers in the resistant cell lines, there were also changes in autophagy protein markers such as increased expression of cleaved LC3 and a decrease in p62/SQSTM1 expression, particularly in the PacR cells. Beclin-1 and XBP-1 expression, however, were not differentially expressed between the sensitive and both resistant cell lines. Beclin-1 and p62 have been implicated in the regulation of both Bcl-2 and NFκB expression. In order to determine whether the changes in autophagy marker protein expression was an indication of an alternative cell death process or cell survival, proliferation assays were performed with sensitive and resistant cells. Cells were counted after exposure for 7 days with and without 3-Methyladenine, an inhibitor of autophagosome formation. The addition of 3-MA significantly decreased cell number suggesting that autophagy may be a mechanism of cell survival in both taxane resistant models. Given our preliminary data, we propose to further investigate the role of autophagy and other alternative cell death evasion pathways seen in MDA-MB-231 taxane resistant and sensitive breast cancer cells. Our studies aim to improve the understanding of how different mechanisms of cell death evasion contribute to the resistance phenotype. Ultimately our studies may not only improve our understanding of taxane resistance at the bench, but may also provide the framework for formulation of novel therapies that may improve the success of taxane therapy in women with breast cancer in the clinic.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4857.