bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1177: The mutational status of the p53 tumor suppressor gene is a determinant of GSTP1 expression and mediates GSTP1-dependent drug resistance in human glioblastoma
Authors: Antoun Gamil R. , McLendon R , Friedman H , Friedman A , Bigner D , Ali-Osman F
Published: August 2012

Mutations in the p53 tumor suppressor gene, a transcription factor activated by a variety of cellular stresses, including, those inflicted by anti-cancer agents, is a common genetic abnormality in GBMs. Although, p53 is involved in critical cellular processes, such as, cell cycle arrest, DNA repair and apoptosis, studies of p53 in tumor drug resistance and/or patient response to therapy have yielded mixed results. Thus, in gliomas and other cancers, such as, breast, bladder, and ovarian carcinomas, some studies have associated wild-type p53 with higher tumor drug resistance, while other studies indicate that mutant or functionally inactive p53, rather than wt p53, confers drug resistance. These observations indicate the significant complexity of the role of p53 in tumor response to therapy and suggest that other factors, including, downstream p53 pathways and/or regulation, may be important determinants of the p53 effects on the tumor drug resistance phenotype. We previously reported that the human GSTP1 gene, that encodes a major drug metabolizing protein, cell signaling regulator and a mediator of tumor drug resistance, is transcriptionally activated by p53 via a canonical p53 binding motif located in intron 4 of the GSTP1 gene. Our goal, in this study, is to gain further insight into the relationship between p53-dependent transcriptional control of GSTP1 in GBM and the extent to which it contributes to GSTP1 expression in primary patient tumor and, ultimately, to their response to therapy. For this, we sequenced the p53 gene across exons 2-11 in 42 primary GBM specimens quantified the level of GSTP1 gene expression by RNA-PCR and genotyped the allelic variants in them. The results showed, approx. half of the tumors to harbor wild-type p53. In those with mutant p53, the mutations spanned the entire p53 target region, the majority in the core DNA binding domain with the hot spots in codons 55, 72, 175, 245, 248, and 273. GSTP1 expression was significantly heterogeneous between the tumors, and with a few exceptions, correlated directly with the presence of wild-type p53. In representative tumors, the high GSTP1 gene expression was associated with resistance to cisplatin and temozolomide. These result suggest that, in GBM, transcriptional activation of GSTP1 by wild-type, and some mutant forms of p53, contributes to their resistance to therapy. Supported by NIH grants RO1 CA 153050, RO1CA127872, RO1 CA 112519, P50CA108786 and P30-CA14236.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1177. doi:1538-7445.AM2012-1177
Abstract 118: CTCF, a master epigenetic regulator, is a haploinsufficient tumor suppressor gene in multiple cell lineages
Authors: Moore James M. , Moser Russell , Smith Leslie , Gurley Kay , Liggett Denny , Filippova Galina , Kemp Christopher J.
Published: August 2012

While changes in the epigenetic landscape are ubiquitous in cancer, the origin and causal effects of most of these changes on neoplastic progression are largely unknown. The DNA binding protein Ctcf, regulates a diverse array of epigenetic processes, including DNA methylation spreading, but is role in cancer is unclear. Here we show that Ctcf heterozygous knockout mice are remarkably susceptible to spontaneous, ionizing radiation, and chemically-induced neoplasia in a broad range of tissues. Analysis of lung tumors from Ctcf+/− mice establishes Ctcf as a haploinsufficient tumor suppressor gene whose loss cooperates with mutant Kras to accelerate tumor growth and malignant progression. Increased DNA methylation at Ctcf binding sites in normal tissues from Ctcf+/− mice indicates that reduction of Ctcf leads to epigenetic deregulation and this occurs prior to overt neoplastic transformation. This indicates epigenetic instability can predispose a broad range of tissues to neoplastic transformation. A mouse model of Ctcf regulated epigenetic stability provides a useful setting to dissect the mechanistic link between environmental exposure, and risk of cancer or other diseases with an epigenetic component.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 118. doi:1538-7445.AM2012-118
Abstract 1306: p63 functions as an essential oncogene in squamous cell carcinoma in vivo and is required for tumor maintenance
Authors: Ramsey Matthew R. , Wilson Catherine , Ory Benjamin , Rothenberg S. Michael , Faquin William , Mills Alea A. , Ellisen Leif W.
Published: August 2012

Transcription factors mediate diverse functions in normal development and tumorigenesis. The p53-related transcription factor p63 (TP63) plays an essential role in development of stratified epithelial tissues, as germline loss of p63 leads to abnormal proliferation and differentiation of ectoderm-derived precursors. The role of p63 in human cancer, however, is controversial. Loss of p63 is associated with neoplastic progression in some animal models and in a subset of human tumors. Nevertheless, p63 is rarely targeted for somatic mutational inactivation and is indeed overexpressed in squamous cell carcinomas (SCCs), where is has been postulated to function either as a key tumor maintenance factor or as a lineage marker not essential to the malignant process. Here, we show that SCCs are profoundly dependent on p63 expression in vivo, and we identify a key, therapeutically relevant pathway through which p63 mediates tumor maintenance. Conditional genetic ablation of p63 in an endogenous SCC model induces rapid and dramatic tumor regression owing to apoptosis of p63-expressing cells. We identify the FGFR2 oncogene as a direct transcriptional target of p63 that signals through AKT to mediate survival of SCC cells. Finally, we employ the clinical FGFR2 inhibitor AZD4547 to demonstrate the potential therapeutic effect of extinguishing FGFR2 signaling in p63-expressing SCCs. These results define p63 as a key tumor maintenance factor through regulation of FGFR2 signaling in SCC. More broadly, this demonstrates the potential for targeting oncogenic transcription factor pathways in tumors such as SCC that rarely exhibit somatic oncogene-activating mutations.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1306. doi:1538-7445.AM2012-1306
Abstract 1311: Expression and activity of nuclear factor TOX3 in breast cancer
Authors: Seksenyan Akop , Kadavallore Asha , de la Torre Brian , Aliahmad Parinaz , Asirvatham Ananthi , Walts Ann E. , Bose Shikha , Berel Dror , Strom Samuel , Funari Vincent , Audeh William , Kaye Jonathan
Published: August 2012

Our laboratory has shown that thymocyte selection-associated HMG-box protein (TOX) is a member of a small subfamily of DNA binding factors, and a key regulator of multiple aspects of immune system development. Recently, genome wide association studies have mapped a breast cancer susceptibility locus to the gene encoding the TOX-family member TOX3. However, little is known concerning the pattern of expression or biological functions of TOX3 in breast cancer and normal mammary epithelial cells. We find that TOX3 is specifically expressed in estrogen receptor (ER+) mammary luminal epithelial cells. Interestingly, using a TOX3 monoclonal antibody developed by our laboratory, we identify a subset of breast tumors that highly express TOX3. Moreover, using the MCF-7 breast cancer cell line, we find that TOX3 regulates a subset of ER target genes in an estrogen independent but ER dependent manner, potentially revealing a novel mechanism of ER target gene activation. In addition, TOX3 enhances cell migration. Together, these studies lend support to the idea of altered TOX3 expression influencing breast cancer development and/or progression.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1311. doi:1538-7445.AM2012-1311
Abstract 1316: N-acetyl-L-cysteine sensitizes pancreatic cancer therapy by targeting NFκB pathway: Translation into animal model
Authors: Qanungo Suparna , de Klerk Uys Joachim , Distler Anne , Mieyal John J. , Lemasters John J. , Townsend Danyelle M. , Nieminen Anna-Liisa
Published: August 2012

Pancreatic cancer has the worst prognosis of all major cancers with 97% treatment failure. First-line systemic therapy for pancreatic cancer is the antimetabolite gemcitabine. Although, tumors may initially respond to the gemcitabine treatment, soon tumor resistance and excessive toxicity develops leading to treatment failure. Efforts to optimize and improve the efficacy of gemcitabine therapy through combination with other agents have little success. Previously, we demonstrated that N-acetyl-L-cysteine (NAC), a glutathione (GSH) precursor prevents NFκB activation and promotes pancreatic cancer cell death. The mechanism of inactivation of NFκB by NAC supplementation is a post-translational sulfhydryl modification called S-glutathionylation on p65-NFκB that inhibits its DNA-binding capacity and thus prevents activation of the survival genes. Mass spectrometric analysis indicated that four of the 9 cysteines of p65 are potentially S-glutathionylated. Our hypothesis is that chemoresistance against gemcitabine arises from a combination of hypoxia- and gemcitabine-induced NFκB activation. The objective of this study is to test the hypothesis and investigate if thiol donors like NAC can suppress NFκB signaling and augment a therapeutic response to gemcitabine in vivo. Here we determined the anti-tumor effect of gemcitabine and NAC on pancreatic tumors in mice. MIA PaCa-2 pancreatic cancer cells were injected into nude mice to grow subcutaneous tumors. Treatment groups were untreated, NAC, gemcitabine and gemcitabine+NAC. Results indicated that neither gemcitabine nor NAC by itself was effective in decreasing tumor growth. However, NAC and gemcitabine in combination inhibited tumor growth by 33%. Gemcitabine activates NFκB, although the mechanism for this phenomenon is unclear. NFκB activity was indeed increased in gemcitabine-treated tumors (3-fold) and combination with NAC treatment blunted this effect (p<0.005). The results confirm gemcitabine-induced NFκB activation and NAC bioavailability in tumors. To assess whether combined treatment of gemcitabine and NAC induces apoptosis, we performed TUNEL staining in tissues. Gemcitabine plus NAC increased apoptosis by 35-fold compared to gemcitabine alone. Taken together, our data suggest that NAC first inhibits NFκB activation arising from hypoxic regions of tumors and secondarily block gemcitabine-activated NFκB in hypoxic and normoxic regions of tumors, and therefore sensitizes cells to gemcitabine-induced killing. This could be used as an effective adjunct to gemcitabine chemotherapy of pancreatic cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1316. doi:1538-7445.AM2012-1316
Abstract 1319: Establishment and characterization of fresh primary human colorectal tumor implants
Authors: Miagkov Alexei , Uzgare Rajneesh , Zhong Shaobin , Leary Lisa , Ondrus Janine , Hundley Thomas , Sathyamoorthy Malathi , Tiruchinapalli Dhanrajan , Todaro Nicole , Griffin Christina , Mulpuri Rao , Hostin Damon , Otto Jeffery , Chen Hao
Published: August 2012

A personalized approach towards the therapy of colorectal carcinoma is critical for a successful outcome. In recent years, direct transfer xenograft models (or the “tumor graft”) have proven to be highly predictive and are being adapted in clinical practice. However, direct drug evaluation in tumor graft models for each individual patient is not feasible due to time and cost constraints. Predictive biomarker discovery is an extremely promising application of the tumor graft model, since the discovered biomarker signatures will direct therapy choice in a much broader patient population. In collaboration with the Catholic Health Initiatives Center for Translational Research we at Caliper Life Sciences have established a collection of tumor graft samples of primary human colorectal carcinomas. All samples were collected fresh from consenting patients following an IRB-approved protocol and implanted in vivo on the day of surgical tumor resection. Tumors were grafted either orthotopically or subcutaneously in female NIH-III mice. We present here the results of a comparative study of gene and protein expression profiles for the primary tumor (clinical samples) and the direct transfer xenografts. These data will be correlated with drug sensitivity profiles generated by using the same samples. The resulting data sets will be used to characterize predictive biomarker signatures that will be a valuable tool for selection of the most effective therapy tailored to the individual patient.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1319. doi:1538-7445.AM2012-1319
Abstract 1377: Characterisation of mechanisms of resistance to sunitinib in a unique pre-clinical RCC model
Authors: Taylor Melissa , Barthélémy Amélie , Escudier Bernard , Farace Françoise
Published: August 2012

Background: Resistance to sunitinib, a broad spectrum tyrosine kinase inhibitor considered as first-line therapy for advanced clear cell renal carcinoma (ccRCC), is almost inevitable in patients. However, understanding the mechanisms underlying resistance to sunitinib remains incomplete. In order to decipher underlying drug-induced resistance mechanisms and identify potential targets to overcome sunitinib resistance in ccRCC, we developed a unique ccRCC xenograft model that mimicked clinical resistance to sunitinib. Methods: Untreated and sunitinib-treated Balb/C mice xenografted with RENCA cells were monitored for tumor growth. Sunitinib (40 mg/kg/day) administered 5 days/7 initially inhibited growth of xenografts, but tumors escaped after 6 weeks of continuous therapy. These sunitinib-induced resistant tumors were then removed and re-implanted to naïve Balb/C mice where re-implanted tumors exhibited immediately an aggressive phenotype. Re-implanted sunitinib-resistant tumors remained refractory to further treatment with sunitinib but responded to treatment with sorafenib and rapamycine, mimicking a strategy and tumor response that is often observed in the clinical setting. Transcriptomic and proteomic analyses of untreated, sunitinib-responsive and sunitinib-resistant tumors were performed, as well as evaluations of microvessel densities and host circulating angiogenic cells. Results: The aggressive phenotype of re-implanted sunitinib-resistant tumors suggested that the drug-induced acquired resistance was of intrinsic nature. However, transcriptomic analyses showed no differences in gene expression levels between untreated, sunitinib-responsive and sunitinib-resistant tumors. Proteomic analyses of tumors and serum samples are ongoing, as well as thorough analyses of the different angiogenic cellular compartments underlying host microenvironment responses. Conclusion: We have established a unique xenograft ccRCC model that mimicks clinical resistance to sunitinib. Our results show that while sunitinib-induced resistance is apparently intrinsic, tumor and host microenvironment are most likely critical mediators of resistance.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1377. doi:1538-7445.AM2012-1377
Abstract 1406: A new ovarian cancer metastasis model using multicellular spheroids generated from human ovarian cancers tissues
Authors: Sun Guigin , Meng Fanliang , Zhong Mei , Yu Yanhong , Shan Weiwei , Anderson Matthew , Brewer Molly A.
Published: August 2012

Objective Most research aimed at dissecting the mechanism by which epithelial ovarian cancer (EOC) metastasizes has focused on the ability of individual cells to attach and create tumor implants. However, multicellular aggregates known as spheroids are frequently found in ovarian cancer ascites and these aggregates are increasingly thought to play an important role in metastasis not only for ovarian cancer but also other solid tumors where similar phenomena have been observed. We investigated characteristics of spheroids compared to cells grown in monolayer to further characterize these spheroids. Methods IRB approval was obtained for collection of human tissue. Fresh specimens of ovarian cancer were minced, enzymatically digested, rinsed and incubated either in DMEM to generate monolayer cultures or Mammosphere media to generate spheroids. Tumorigenicity was assessed by inoculating individual spheroids or an equal number of dissociated cells into the peritoneal cavity of SCID mice. Gene expression was examined using Western blot and quantitative real-time PCR. Results We found that cells from most ovarian cancers do generate spheroids and most of the spheroids generated are able to reliably induce peritoneal implants in SCID mice. At a molecular level, the spheroids were enriched for expression of specific markers including CD133, CD44, NANOG and OCT4, associated with populations of cancer initiating cells (CICs) as well as other stem cell markers. MiR-26b, characteristic of CICs, was significantly up regulated in spheroids compared to monolayer cells. Spheroids from CD133 positive cells induced ovarian and abdominal tumors in SCID mice, however, CD44 spheroids only generated localized tumor, suggesting that CD133 is important in metastasis of ovarian cancer. Conclusion Our results indicate that populations of cells from human EOC are capable of spontaneously generating multicellular aggregates that resemble the spheroids found in ovarian cancer ascites de novo. These spheroids are enriched for expression of markers including CD133, CD44, NANOG and OCT4, suggesting that spheroid formation enhances stem cell-like markers. CD133 might also serve as a necessary marker for metastasis of ovarian cancer. The increased expression of miR-26b in spheroids compared to monolayer culture is a novel finding that needs further investigation.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1406. doi:1538-7445.AM2012-1406
Abstract 162: Biomarker identification of residual triple negative breast cancer (TNBC) after standard neoadjuvant chemotherapy (NCT)
Authors: Sohn Joohyuk , Liu Shuyling , Chen Huiqin , Meng Xiaolong , Do Kim-Anh , Mills Gordon B. , Hortobagyi Gabriel N. , Meric-Bernstam Funda , Gonzalez-Angulo Ana M.
Published: August 2012

Backgrounds Residual TNBC after standard NCT has a poor prognosis. The aim of this study was to identify biomarkers that correlate with prognosis and can be used as novel therapeutic targets in this disease Methods 54 residual TNBC were identified. Protein was extracted and 76 antibiotics to proteins related to breast cancer signaling were measured by reverse phase protein arrays (RPPA). Univariable and multivariable Cox proportional hazard model ratios were fitted for each protein and simultaneously. Cross-validation was also performed. The coefficient in the multivariable Cox model were used to calculate a risk score (RS) for each sample. Results The unsupervised clustering analysis of the proteomic profiles for the 54 residual breast cancers and 76 proteins divided the tumors into two groups without significant survival difference. Multivariable analysis using the top 25 proteins from univariable analysis at a false discovery rate (FDR) of 0.3 showed that IGFPB2, LKB1, and S6 were significant predictors in relapse free survival (RFS). RS model calculated based on multivariable analysis was 0.3746*IGFPB2-0.8852*LKB1+0.6012*S6, AUC=0.807. Employing crossvalidation the model was found to be reproducible. Multivariable analysis suggested that RS was an independent predictor of RFS (HR: 2.705, 95% CI 1.549 to 4.723, P-value=0.0005). Conclusions We identified a RS of three biomarkers that predict outcome in patients with residual TNBC that could be studied as therapeutic targets for this disease.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 162. doi:1538-7445.AM2012-162
Abstract 1621: Potent anti-cancer effect of crocin against hepatocellular carcinoma: A preclinical study
Authors: Amin Amr , Schneider-Stock Regine , Daoud Sayel
Published: August 2012

Background: This is a follow up of our study published in September issue of Hepatology and featured in October issue of Science News that documented the antic-cancer potential of saffron. Here, we show the chemopreventive actions and mechanisms of saffron-based bioactive ingredient; crocin, against diethylnitrosamine (DEN)-induced liver cancer in rats. Methods: Administration of crocin at two doses of 100 and 200 mg/kg body wt per day was started two weeks prior to the DEN injection and was continued for 22 weeks. Result: Crocin decreased the number and the area of placental glutathione-S-transferase positive foci in livers of DEN-treated rats. Furthermore, crocin counteracted DEN-induced oxidative stress in rats as assessed by restoration of superoxide dismutase, catalase, and glutathione-S-transferase levels and diminishing of myeloperoxidase activity, malondialdehyde and protein carbonyl formation in liver. The results of immunohistochemical staining of rat liver showed that crocin inhibited the DEN-mediated elevations in numbers of cells positive for Ki-67, cyclooxygenase 2, inducible nitric oxide synthase, nuclear factor-kappa Bp-65 and the phosphorylated tumor necrosis factor receptor. Crocin also blocked the depletion in the number of cells positive for TUNEL and M30 CytoDeath in liver tissues of DEN-treated rats. In vitro experiments carried out using HepG2 cells also confirmed these findings and showed inhibition of NFkB activation, increased cleavage of caspase-3, as well as DNA damage and cell cycle arrest upon saffron treatment. Conclusion: The present study provides evidence that crocin exerts a significant chemopreventive effect against liver cancer through inhibition of cell proliferation and induction of apoptosis. This report also shows some evidence that crocin protects rat liver from cancer via modulating oxidative damage and suppressing inflammatory response. This study is funded by Emirates Foundation.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1621. doi:1538-7445.AM2012-1621
Abstract 1638: Aspirin acetylates multiple cellular proteins in HCT-116 cells: Identification of novel targets
Authors: Gunaje Jayarama B. , Marimuthu Srinivasan , Chivukula Raghavender S.V. , Moridani Majid , Hagen Fred K. , Alfonso Lloyd F.
Published: August 2012

Aspirin, a non-steroidal anti-inflammatory drug has been consistently associated with a reduced risk of colon cancer; however, the molecular mechanisms are not completely understood. In the present study, we determined the ability of aspirin to acetylate, and post-transnationally modify cellular proteins in HCT-116 human cancer cells to understand the potential mechanisms by which it may exert anti-cancer effects. Using anti-acetyl lysine antibodies, here we demonstrate that aspirin causes the acetylation of multiple proteins whose molecular weight ranged from 20 to 200 kDa. The identity of these proteins was determined, using immune-affinity purification, mass spectrometry and immunoblotting. A total of 33 cellular proteins were potential targets of aspirin-mediated acetylation, while 16 were identified as common to both the control and aspirin-treated samples. These include enzymes of glycolytic pathway, cytoskeletal proteins, histones, ribosomal and mitochondrial proteins. The glycolytic enzymes which were identified include aldolase, glyceraldehyde 3 phosphate dehydrogenase, enolase, pyruvate kinase M2, and lactate dehydrogenase A and B chains. Immunoblotting experiments showed that aspirin also acetylated glucose 6-phosphate dehydrogenase and transketolase, both enzymes of pentose phosphate pathway involved in ribonucleotide biosynthesis. In vitro assays of these enzymes revealed that aspirin did not affect pyruvate kinase and lactate dehydrogenase activity; however, it decreased glucose 6-phosphate dehydrogenase activity. Selective inhibition of glucose 6-phosphate dehydrogenase and other key proteins through acetylation may represent important mechanisms by which aspirin may exert its anti-cancer effects.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1638. doi:1538-7445.AM2012-1638
Abstract 1650: Overview of the clinical ELLIPSE (ELucidating Loci Involved in Prostate cancer SuscEptibility) Consortium (CEC)
Authors: Goh Chee L. , Schumacher Fredrick , Kote-Jarai Zsofia , Kraft Peter , Easton Douglas , Henderson Brian , Eeles Rosalind
Published: August 2012

Background The inherited link of prostate cancer (PrCa) has led to large scale Genome Wide Association Studies (GWASs), which aim to identify susceptibility loci associated with PrCa. Currently, these Single Nucleotide Polymorphisms (SNPs) have only been evaluated against overall PrCa risk and several disease parameters. The challenge now is to translate these genetic risk algorithms into the clinical setting. This has led to NIH (National Institute of Health) funded post-GWAS initiatives in PrCa and the establishment of the Clinical ELLIPSE Consortium (CEC) to harmonise genetic, clinical and epidemiological data from existing consortia around the world. This will provide the necessary guidance in developing useful and powerful risk prediction models for PrCa risk, including screening outcome and treatment effects. These risk prediction models may have an immediate public health impact by providing clinicians with the necessary tools to improve clinical decision making. Methods Several projects are currently underway including the analysis of Active Surveillance outcomes against these SNPs, and the analysis of the PRACTICAL (PRostate cancer AssoCiation group To Investigate Cancer Associated aLterations in the genome) consortium cohort, looking at the association of these SNPs with disease parameters. Collaborations have been established with ERSPC (European Randomized Study of Screening for Prostate Cancer), STAMPEDE (Systemic Therapy in Advanced or Metastatic Prostate cancer: Evaluation of Drug Efficacy) and RAPPER (radiogenomic) consortia, to analyse these SNPs’ role in screening and treatment outcomes. Results An inventory collected across the consortium showed that there are 59688 cases and 191698 controls with clinical data. There were also large numbers of tumour (11982 samples) and blood (43624 samples) available. These figures are very encouraging and discussions are currently underway to access and combine data across the groups for analyses. Conclusion The CEC provides the necessary framework needed to foster successful collaborations and begin the transition from ‘bench-side’ research to ‘bed-side’ care. Acknowledgments This project is supported by The NIH grant: No. 1 U19 CA 148537-01 and Cancer Research UK.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1650. doi:1538-7445.AM2012-1650
Abstract 1663: Mapping genes that predict treatment outcome in admixed populations
Authors: Baye Tesfaye Mersha , Wilke Russell A.
Published: August 2012

There is great interest in characterizing the genetic architecture underlying drug response. For many drugs, gene-based dosing models explain a considerable amount of the overall variation in treatment outcome. As such, prescription drug labels are increasingly being modified to contain pharmacogenetic information. Genetic data must, however, be interpreted within the context of relevant clinical covariates. Even the most predictive models improve with the addition of data related to biogeographical ancestry in admixed population. Admixture influences populations in a manner different from geographic race or cultural ethnicity. When two genetically distinct populations interbreed, a set of unique relationships are created among sets of variants across the genome. This phenomenon results in the formation of long segments of DNA with distinguishable ancestral origins. Risk alleles carried within these segments can influence treatment outcome in a variety of contexts. As the scientific community moves toward characterization of outcome in diverse cohorts with DNA biobanks linked to comprehensive electronic medical records, a great need exists for the development of flexible, robust analytical strategies that leverage admixture to optimize the study of pharmacogenomics. We presented analytical strategies to develop ancestry informative marker (AIM) that leverage population structure to more fully characterize genetic determinants of outcome in large clinical practice-based admixed cohorts. Keywords: Admixture, ancestry, Ancestry Informative Markers, AIMs, admixture mapping, ancestry, biobank, database, pharmacogenetics

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1663. doi:1538-7445.AM2012-1663
Abstract 1668: Understanding cancer associated SNPs in the TERT-CLPTM1L locus through population genetics
Authors: Mirabello Lisa , Chung Charles , Yeager Meredith M. , Savage Sharon A.
Published: August 2012

Telomeres form the ends of eukaryotic chromosomes and are vital in maintaining genetic integrity. TERT encodes the telomerase reverse transcriptase, which is responsible for maintaining telomere ends by addition of (TTAGGG)n nucleotide repeats at the telomere. Recent genome-wide association studies have found common genetic variants at theTERT-CLPTM1L locus (5p15.33) associated with increased risk of several cancers, including glioma, basal cell carcinoma, testicular, pancreatic, breast and lung cancers, and possibly overall cancer risk. Our prior studies of common single nucleotide polymorphisms (SNPs) in the TERT gene region found low differentiation among populations and higher than expected levels of haplotype diversity in data from the Human Genome Diversity Panel (HGDP) and the International HapMap Project. In the current study we significantly expanded the population genetic analyses by utilizing data from the 1000 Genomes Project (2011 October release). Genetic variation from a total of 1092 individuals from 14 populations with European, East Asian, West African or American ancestry was evaluated. Data were acquired for 3468 variants in a 206kb region on 5p15.33, which included the TERT-CLPTM1L gene and flanking regions. The GLU genetics’ ld.tagzilla module was used for the tag analysis with a linkage disequilibrium (LD) pairwise r2 threshold of 0.8. Arlequin (3.5) and Genepop (4.1) packages were used to estimate diversity, LD, heterozygosity, and differentiation (FST) among populations. Pairwise LD was analyzed separately for the 4 ancestral groups (European, East Asian, West African and American) and used to select tag SNPs for each region. The 4 ancestral groups had differing LD patterns with the lowest level of LD occurring in individuals from Africa, as expected. These data were used to create the appropriate haplotype-tagging SNPs for the TERT-CLPTM1L region in each population; we present recommended tagging SNPs by ancestral group. The TERT-CLPTM1L gene region had low nucleotide diversity (mean 2 x 10−4) and differentiation among ancestral groups (90% of loci in this region had FST <0.10). The limited diversity in this region may be due to its critical role in telomere maintenance and chromosomal stability. The recently identified cancer associated SNPs in this region had differing genotype frequencies among ancestral groups. Variation in cancer associated alleles among ancestral groups may correlate to varying disease risks.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1668. doi:1538-7445.AM2012-1668
Abstract 1688: Relevance of mTOR pathway in prognosis of patients with urothelial carcinoma of the bladder
Authors: Fahmy Mona , Mansure Jose Joao , Brimo Fadi , Yafi Faysal , Segal Robert , Althunayan Abdulaziz , Netto George , Meeker Alan , Hicks Jessica , Kassouf Wassim
Published: August 2012

Purpose. To investigate the role of mTOR signalling pathway on stage and outcome of patients with high grade and/or invasive bladder cancer. Methods. Tissue microarrays were built from archival of high grade and mostly superficial bladder tumour specimens (n=143 with complete clinical data collected). Immunohistochemical staining was performed for Phosphatase and tensin homolog (Pten), phosphorylated (phos) Akt, phos-mTOR, phos-S6, phos-4EBP1 and p27. The markers were evaluated for pattern, percentage and intensity of staining (H-score), and results correlated with clinicopathological characteristics and outcome. Results. The median age at diagnosis of the patient cohort was 71 years (range: 38-96 years). The TNM stage group was distributed as pTa (44%), pT1(49%) and pT2 (6%). After a median follow-up of 34 months, the disease recurrence, disease progression and overall death rates were 44%, 13%, and 11% respectively. The expression of p27 was significantly lower among pT2 compared to pTa and pT1 patients (p < 0.03). The H-score of phos-mTOR was significantly correlated with p27 (p <0.003), pS6 (p < 0.004) and 4EBP1 (p <0.001). In multivariate analysis, which included age, number of tumors, tumor size and stage, phos-S6 was an independent predictor of shorter recurrence-free (Hazard Ratio [HR]: 2.75, 95% Confidence Interval [CI]: 1.16-6.51). The expression of p27 was inversely correlated with recurrence-free survival (HR:0.37, 95% CI:0.18-0.88). None of the markers showed correlation with progression free survival and overall survival. Conclusion. Our results demonstrate that activation of mTOR pathway, as assessed by phosS6 might be used to provide prognostic information particularly as predictor of recurrence among patients with high-risk non-muscle invasive bladder cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1688. doi:1538-7445.AM2012-1688
Abstract 1689: Impact of pre-treatment body mass index on patients with head and neck cancer treated with radiation
Authors: Tsang Ngan M.
Published: August 2012

Purpose: Radiation therapy (RT) may lead to difficulty in swallowing and subsequently weight loss in patients with head and neck cancer. We investigated the association of pre-treatment body mass index (preT BMI) with outcomes of head and neck cancer in patients treated with radiation. Methods: All 1562 patients diagnosed with head and neck cancer and treated with curative-intent RT to a dose of 60Gy or higher between 1994 and 2004 were retrospectively studied. Body weight was measured both at entry and at the end of RT. cancer-specific survival (CSS), overall survival (OS), locoregional control (LRC) and distant metastasis (DM) were analyzed by preT BMI (< 25 Kg/m2 vs ≤ 25Kg/m2). The median follow-up was 8.6 years. Results: Patients with higher preT BMI appeared to have earlier T and N stage. Patients with lower preT BMI were statistically significantly associated with poor CSS (p = 0.023) and OS (p < 0.0001) than those with higher preT BMI. There is no significant difference between high and low preT BMI in LRC and DM. Body weight loss (BWL) during radiation did not influence survival outcomes. However, in the group of higher preT BMI, CSS, OS and DM-free survival of patients with less BWL during radiation was statistically longer when compared with greater BWL (p = 0.002, < 0.0001, and 0.033). Conclusion: This study demonstrates preT BMI greater than or equal to 25 Kg/m2 positively influenced survival outcomes for patients with head and neck cancer. Patients with higher preT BMI who were able to maintain their weight during radiation had significantly better survival and distant outcomes than patients experiencing greater BWL.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1689. doi:1538-7445.AM2012-1689
Abstract 1690: Tumor-educated macrophages promote tumor growth and peritoneal metastasis in an orthotopic nude mouse model of human pancreatic cancer
Authors: Menen Rhiana , Hassanein Mohamed K. , Momiyama Masashi , Suetsugu Atsushi , Moossa Abdool R. , Bouvet Michael , Hoffman Robert M.
Published: August 2012

There is a strong association between poor survival and increased macrophage density in many cancers. In the current study, we determined whether macrophages from tumor-bearing mice (tumor-educated macrophages) had greater tumor-promoting capability than macrophages from non-tumor-bearing mice. Ten transgenic nude mice ubiquitously-expressing GFP were injected subcutaneously with the human pancreatic cancer cell line, BXPC3 stably expressing RFP. GFP-expressing macrophages from tumor-bearing transgenic GFP mice were harvested and defined as “tumor-educated macrophages”. Macrophages were also harvested from transgenic GFP mice (n=10) without subcutaneous tumors and identified as “naïve macrophages.” Three groups of mice were studied: 1) A control group without addition of macrophages (n=10); 2) A naïve group, with weekly intraperitoneal (ip) injection of 106 naïve macrophages per mouse (n=10); and 3) A tumor-educated group, with weekly ip injection of 106 tumor-educated macrophages per mouse (n=10). The study ended with termination of the tumor-educated group after 8 weeks due to a pre-morbid state identified in all mice. At this time, all mice in each of the three study arms were terminated, imaging was performed, and total tumor weight was obtained. In the control group, the average primary tumor weighed 668 mg; only three mice (30%) developed peritoneal metastases with an average weight of 241 mg. The naïve-macrophage group had an average tumor weight of 823 mg (p=0.51); 50% developed peritoneal metastases with an average weight of 975 mg (p=0.029). The tumor-educated-macrophage group had an average primary tumor weight of 2095 mg (p=0.001); 75% of mice developed peritoneal metastases with an average weight of 2135 mg (p=0.008). When comparing naïve- to tumor-educated- groups, primary tumor weight was significantly greater in the tumor-educated group (p=0.003), and the average weight of metastasis was 2.2 times greater in the tumor educated group, however this did not reach statistical significance (p = 0.17). When comparing naïve- to tumor-educated-groups, there was no statistically significant difference with regard to body weight (p=0.87), or weight of metastasis (p=0.68); however primary tumor weight was significantly greater in the tumor-educated group (p=0.013). Tumor-educated-macrophages specifically promote tumor growth progression in an orthotopic nude mouse model of pancreatic cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1690. doi:1538-7445.AM2012-1690
Abstract 1704: AC electrokinetic isolation of cell free high molecular weight DNA (CF-HMW DNA) from serum
Authors: Lu Jerry , Hanna William , Kumosa Lucas S. , Bhalla Megha , Cheung Veronica W. , Turner Robert P. , McCanna James P. , Tu Eugene , Charlot David J. , Krishnan Rajaram
Published: August 2012

Recent reports of CF-HMW DNA in a variety of diseases has led to interest in its use as a prognostic biomarker, a diagnostic or screening tool for cancer. Apoptotic DNA (<200bp) is present in the circulation of normal healthy individuals. In cancer, unregulated cell growth leads to uncontrolled cell death, or necrosis, which produces HMW DNA (>500bp) that is then trafficked into circulation. Dielectrophoresis, or DEP (movement of particles in a non-uniform AC electric field), based electrokinetic techniques have been used for protein biomarker screening, cell separation, and DNA manipulation. Using specific DEP frequencies, analytes are moved to known locations (high or low field region) based on their inherent dielectric properties. The process allows specific nano-sized particles to be highly concentrated into high field regions, while micron-size cells are held weakly in low field regions. With fluidic washing, cells can be removed while nano-sized particles are held in high field regions. This method can effectively act as a CF-HMW DNA enrichment process for biological fluids. Unfortunately, DEP does not work well in (high conductance) physiological buffers, requiring significant dilution of the sample and, as a result, the target analyte concentration. Here, we describe a novel AC electrokinetic (ACE) technique using a custom microelectrode array and AC parameters to isolate and analyze CF-HMW DNA from high conductance serum. DNA from normal serum samples and the A549 cell line were isolated using Qiagen kits to determine initial DNA quantities. Normal sera were spiked with A549 cell line DNA at concentrations from 0 to 500 ng/ml and subjected to a 20 minute ACE protocol. DNA isolation was visualized in situ using SYBR Green I fluorescence and then eluted for use in secondary analyses. Results showed minimal fluorescence from samples without spike whereas A549 DNA spiked samples showed concentration-dependent fluorescence on the microelectrodes. After elution, levels of DNA were quantitated using ALU-sequence based qPCR and K-ras mutational status was confirmed by ABI CastPCR. Future experiments will compare CF-HMW DNA levels from normal and cancer patients across a variety of solid tumors. The ACE technique enables rapid isolation and detection of CF-HMW DNA directly from biological fluids without prior sample prep and has broad utility for diagnosis and monitoring of cancer and other diseases in which CF-HMW DNA may be used as a marker.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1704. doi:1538-7445.AM2012-1704
Abstract 1719: Significance of thymidylate synthase copy numbers for resistance to pemetrexed in lung cancer
Authors: Kasai Daishi , Oguri Tetsuya , Ozasa Hiroaki , Uemura Takehiro , Kunii Eiji , Takakuwa Osamu , Ohkubo Hirotsugu , Miyazaki Mikinori , Maeno Ken , Sato Shigeki
Published: August 2012

Pemetrexed is a multitargeted antifolate with promising clinical activity in non-squamous lung cancer. It targets the folate-dependent enzymes thymidylate synthase (TS), reduced folate carrier, and folylpolygamma-glutamate synthetas, all of which are involved in the de novo biosynthesis of thymidine and purine nucleotides.The primary mechanism of the action of pemetrexed is inhibition of TS, which results in a decrease in the available thymidine necessary for DNA synthesis. We have previously established pemetrexed -resistant lung cancer cell line, and have shown that overexpression of TS resulted in increased pemetrexed resistance. We have also examined that TS copy numbers by quantitative real-time PCR, were increased in pemetrexed-resistant cells. Therefore we investigated TS copy numbers in lung cancer cell lines and clinical samples to examine whether TS copy numbers are the biomarker for pemetrexed sensitivity. First, we examined the correlation of TS copy numbers and 50% cell survival of pemetrexed for 14 lung adenocarcinoma cell lines, and a meaningful relationship was accepted. In addition, we examined TS copy number in 20 bronchoscopic specimens of non-squamous lung cancers, and found that the correlation was also confirmed between TS copy numbers and clinical response. Our study suggests that TS copy number may be a predictive marker for pemetrexed sensitivity in lung cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1719. doi:1538-7445.AM2012-1719