bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 3492: γ-secretase inhibitor PF-03084014 diminishes the tumor-initiating cells and demonstrates synergy with docetaxel in breast cancer xenograft models
Authors: Zhang Cathy C. , Yan Zhengming , Zong Qing , Fang Douglas , Painter Cory , Zhang Qin , Pavlicek Adam , Lira Maruja E , John-Baptiste Annette , Christensen James
Published: August 2012

Notch signaling is known to be a survival pathway for tumor-initiating cells. In this report, we demonstrate that the γ-secretase inhibitor PF-03084014 significantly enhances the antitumor activity of docetaxel in multiple xenograft models of triple-negative breast cancer. Mechanistic evaluation revealed that PF-03084014 perturbs the Notch signaling pathway and suppresses the function of tumor initiating cells (TIC). In MDA-MB-231Luc model, treatment of docetaxel led to a significant increase of CD133+/CD44+ and ALDH+ subpopulations by FACS analysis. In combination with PF-03084014, these two unique cell subpopulations were significantly diminished. Correspondingly, the functional analyses by tumor re-implant and mammosphere-forming efficiency assays revealed that docetaxel-therapy promoted the tumor initiating capability of the remaining cells, in which an increased stem cell property and Notch pathway activation were observed through gene signature changes. In contrast, PF-03084014 co-treatment with docetaxel substantially hampered the self-renewal ability of these cells. Notch target gene analysis demonstrated the biological relevance of PF-03084014-induced activity. To characterize the function of CD133+/CD44+ subpopulation, MDA-MB-231Luc tumors were de-bulked by the treatment with docetaxel. Subsequently, the CD133+/CD44+ and CD133-/CD44- subpopulatons were isolated and re-implanted in SCID-bg mice using a limiting dilution approach. The results showed that CD133+/CD44+ cells gave rise to tumors with a 100 % take rate (10/10), whereas CD133-/CD44- cells were not tumorgenic (0/10). In addition, CD133+/CD44+ cells exhibited much higher tumorigenicity compared with the respective adherent parental cell line. PF-03084014 treatment caused a significant delay of CD133+/CD44+ tumor growth. The ability of PF-03084014 to suppress TICs was also observed in other breast cancer xenografts, including patient derived models. This data suggests that anti-TIC is one of the contributing mechanisms for the synergistic activities of PF-03084014 in combination with docetaxel. Our work provides potential therapeutic opportunities for PF-03084014 to improve conventional cytotoxic therapy by inhibiting Notch signaling in tumor-initiating cells and other bulk tumor cells.

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 3492. doi:1538-7445.AM2012-3492
Abstract 3500: T cells redirected against HER2 for the adoptive immunotherapy for HER2-positive osteosarcoma
Authors: Ahmed Nabil , Brawley Vita , Diouf Oumar , Anderson Peter , Hicks John , Wang Lisa , Dotti Gianpietro , Wels Winfried , Liu Hao , Gee Adrian , Rooney Cliona , Brenner Malcolm , Heslop Helen , Gottschalk Stephen
Published: August 2012

INTRODUCTION: The prognosis for patients with advanced osteosarcoma (OS) has not improved over the last two decades. Hence novel biologically-based therapies, such as immunotherapy, are needed for these patients. We have shown in preclinical studies that T cells, genetically modified with a HER2-specific chimeric antigen receptor (CAR; HER2-CAR T cells), kill HER2+ OS cells ex vivo and induce regression of HER2+ OS xenografts in animal models. Based on these findings we developed a Phase I/II clinical study with HER2-CAR T cells in patients with metastatic and/or recurrent OS. METHODS: The primary objective of this clinical trial is to determine the safety of escalating doses of HER2-CAR T cells in patients with advanced HER2+ OS. The secondary objective is to determine the expansion, persistence and anti-tumor effects of infused HER2-CAR T cells. RESULTS: 43 (78%) out of 55 screened OS patients had HER2+ tumors. Twenty one HER2-CAR T-cell lines have been generated to date by retroviral transduction. Median HER2-CAR expression was 67.4% (range 50.7-85.6%) and HER2-CAR T cells killed HER2+ OS cells in contrast to non-transduced T cells (p <0.0001). The median CD4+:CD8+ T-cell ratio was 1:1.3, and T-cell products contained naïve (CD45RA+; median: 11.8%; range 2.4-33.2%), effector memory (CD45RO+/CCR7-/CD62L-; median: 29.3%; range: 7.8-67.5%), and central memory T cells (CD45RO+/CD62L+; median 55.9%; range: 21.9-87.9%). Nine patients have been infused so far at HER2-CAR T-cell doses between 104/m2 to 1x106/m2. Infusions were well tolerated without systemic side effects, and no increase of proinflammatory cytokines (IL-2, IFN-γ, GM-CSF, TNF-α) was observed in the patients’ plasma post infusion. HER2-CAR T cells were detectable for up to 3 months post infusion. CONCLUSION: HER2-CAR T cells have shown promising antitumor activity in preclinical OS animal models. We are currently evaluating the safety and efficacy of HER2-CAR T cells in a Phase I/II clinical study. Initial safety data at low T-cell dose levels are encouraging, warranting further active exploration of HER2-CAR T-cell based therapies for OS and other HER2+ malignancies.

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 3500. doi:1538-7445.AM2012-3500
Abstract 3539: Anti-CSF-1R antibodies reduce tumor-associated macrophages and inhibit tumor growth in preclinical models
Authors: Doody Jacqueline , Mathew Sneha , Wu Lan , Li Yanxia , Wang Ying , Persaud Kris , Burtrum Douglas , Balderes Paul , Surguladze David , Haurum John , Ludwig Dale
Published: August 2012

In cancer, increased infiltration of macrophages within and surrounding the tumor mass correlates with increased tumor invasiveness and growth. In addition, presence of tumor-associated macrophages (TAMs) has been shown to correlate with poor prognosis, particularly in breast, prostate, ovarian and cervical cancer. TAM proliferation, differentiation and survival is dependent on Colony Stimulating Factor - 1 Receptor (CSF-1R) activation, a type III integral membrane tyrosine kinase receptor selectively expressed on cells of the mononuclear phagocyte lineage. Given that TAMs enhance tumor growth and that activation of the CSF-1R pathway is required for TAM function, an antibody against mouse CSF-1R was generated for proof-of-principle studies. CS7, a monoclonal anti-mouse CSF-1R antibody inhibited both CSF-1 and IL-34 binding to mouse CSF-1R, leading to inactivation of the receptor and downstream signaling molecules. In addition, CS7 prevented monocyte proliferation and macrophage differentiation with IC50s of 0.1 nM and 0.75 nM, respectively. In murine models of breast cancer using CSF-1-secreting MDA-MB-231, Hcc1954, 4T1 or EMT6 tumor cells, CS7 treatment led to a marked reduction in TAMs and an associated decrease in tumor growth. In contrast, breast tumor xenografts with CSF-1 non-secreting breast tumor cell lines JimT1 and MCF-7 had limited or no decrease in tumor volume following CS7 treatment. In prostate models, DU145 tumor cell line xenografts (CSF-1-secreting) but not PC3 (CSF-1 non-secreting) tumor growth was inhibited by CS7, recaptitulating the results seen with breast xenografts. Thus, in breast and prostate preclinical models, CSF-1 secretion by tumor cells is a prerequisite for sensitivity to anti-CSF-1R treatment. Taken together, targeting CSF-1R with a monoclonal antibody inhibits CSF-1R signaling via CSF-1 and IL-34, prevents monocytic to macrophage differentiation, and reduces tumor volume in preclinical models, validating CSF-1R as a target for therapeutic application in 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 3539. doi:1538-7445.AM2012-3539
Abstract 3665: An EMT gene expression diagnostic predicts resistance to EGFR and MEK-targeted therapies in cell lines and patients
Authors: Eddy Sean F. , Williams Paul , Tomilo Mark , Sadis Seth , Wyngaard Peter , Vo Lien , Oades Kahuku , Kim Hyunsoo , Wang Yipeng , Lee Byung-In , Monforte Joseph , Rhodes Daniel
Published: August 2012

The epithelial to mesenchymal transition (EMT) in cancer cells results in the acquisition of metastatic properties and may contribute to chemoresistance. Several studies have shown that transition to a mesenchymal phenotype leads to decreased dependence on EGFR-RAS signaling and insensitivity to EGFR inhibitors. To better understand the importance of EMT as a general predictor of drug response, we defined an EMT gene signature derived from a meta-analysis of differential gene expression signatures representing genes up-regulated following transfection of breast cell lines with various EMT regulators (Taube et al., 2010 Proc Natl Acad Sci USA 107:15449-54). We then determined the expression of the EMT signature across cell line panels and determined whether it predicted sensitivity or resistance to various targeted therapies. Consistent with previous results, expression of EMT signature was significantly associated with resistance to an EGFR inhibitor, lapatinib. Similarly, the EMT signature also predicted resistance to PQIP (IGF1R), GSK1120212 (MEK), GSK690693 (AKT), and perifosine (AKT/PI3K), suggesting that EMT may be a common resistance mechanism to a number of drugs that target growth factor signaling. As more of these targeted agents are entering clinical trials, the ability to characterize the signature may have important implications for drug development. To study the relevance of the EMT signature in clinical tumors, we compared the signature to a collection of tumor co-expression patterns, known as OncoScore modules, which were defined from 40,000+ tumor microarray experiments. Notably, the EMT signature was significantly associated with a major tumor co-expression pattern representing mesenchymal and/or stromal phenotype observed in almost all major solid tumor types. In retrospective microarray scoring analyses of key clinical datasets, the mesenchymal/stromal module predicted resistance to cetuximab. This finding was validated with an independent cohort of colorectal cancer patients treated with cetuximab using the Oncoscore Colon diagnostic. Oncoscore Colon is a qPCR test optimized for formalin-fixed paraffin-embedded tissue that measures the twelve key colon cancer transcriptional modules, including the mesenchymal module. Because the mesenchymal/stromal module monitors a fundamental phenotype of cancer cells important for drug response, this validated qPCR test has broad application to companion diagnostics development and personalized medicine.

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 3665. doi:1538-7445.AM2012-3665
Abstract 3742: P7170: A potent and oral phosphoinositide 3-kinase (PI3K)-mammalian target of rapamycin (mTOR) and activin receptor-like kinase 1 (ALK1) inhibitor with anti-tumor and anti-angiogenic activity
Authors: Agarwal Veena R. , Joshi Asavari , Venkataraman Magesh , Desai Nikesh , Bhatia Dimple , Chaudhari Sarika , Bose Julie , Kolla Lakshmi Sireesha , Deore Vijaykumar , Yewalkar Nilambari , Kumar Sanjay , Sharma Rajiv , Damre Anagha , More Avinash , Gill Parkash , Sharma Somesh
Published: August 2012

The PI3K/mTOR pathway plays an important role in regulating cancer cell proliferation, growth, survival and metabolism. Activation of the PI3K/mTOR pathway by multiple mechanisms is one of the most frequently observed defects in human malignancies. The objective of these studies was to identify a small molecule that has anti-angiogenic activity in addition to PI3K and mTOR activity. P7170, a novel small molecule, inhibits PI3Kα and mTOR enzyme activity with IC50 value of 2.2 nM and 4.4 nM respectively. P7170 also inhibits a number of PI3Kα mutants. The Inhibition of PI3K-mTOR pathway in different cancer cell lines was demonstrated by 80 to 100% inhibition of the expression of phosphorylated AKT (pAKT), S6 ribosomal protein (pS6), and 4EBP1 (p4EBP1) upon treatment with P7170 in a western blot assay. P7170 also inhibited ALK1, an important enzyme involved in angiogenesis, and DNA-PK, an enzyme involved in DNA repair with the IC50 values of 47 and 1.5 nM, respectively. P7170 exhibited potent cytotoxic activity with IC50 values ranging from 2 to 22 nM in a number of cancer cell lines eg. ovarian (A2780), prostate (PC3), triple negative breast (MDA-MB-231 and MDA-MB-468), ER positive breast (MCF7), hepatocellular (HuH-7), renal (786-O), pancreatic (Panc1, AsPC1, and BxPC3), and colon (HCT116, HCT115, SW480) cancer cell lines. More interestingly, P7170 inhibited pAKT and pS6 in stem-like cells isolated from tumor samples of colon, breast, and head and neck cancer patients. P7170 also inhibited anchorage independent colony formation of tumor cells isolated from 39 different human tumor xenografts derived from tumors of patients with different cancers. In addition, P7170 inhibited angiogenesis in vitro in a tube formation assay, and in a matrigel plug assay in animals. It also inhibited metastasis of breast cancer cells. P7170 demonstrated significant in vivo efficacy when administered orally in three human xenograft tumor models. Tumor growth inhibition of 79% at 15 mg/kg in prostate (PC3), 78% at 10 mg/kg in ovarian (A2780), and 64% at 10 mg/kg in triple negative breast (MDA-MB-231) xenografts. Conclusion: P7170 has a unique profile of PI3K-mTOR pathway inhibition along with anti-angiogenic and anti- DNA repair activities. Combined with its effect on stem-like cells, P7170 may prove to be an effective anti-cancer drug.

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 3742. doi:1538-7445.AM2012-3742
Abstract 3748: NVP-BYL719, a novel PI3Kalpha selective inhibitor with all the characteristics required for clinical development as an anti-cancer agent
Authors: Fritsch Christine M. , Schnell Christian , Chatenay-Rivauday Christian , Guthy Daniel A. , Pover Alain De , Wartmann Markus , Brachmann Saskia , Maira Sauveur-Michel , Huang Alan , Quadt Cornelia , Hofmann Francesco , Caravatti Giorgio
Published: August 2012

Most of the current oncology drug discovery and development work has shifted towards molecularly targeted therapies. A key focus has been on identifying inhibitors against components of pathways that drive tumor cell proliferation, survival, and metastasis such as the PI3K/mTOR pathway, reported to be implicated in many human cancers through various mechanisms, such as, somatic PIK3CA missense mutations that occur at high frequency. These mutations are largely point mutations predominantly clustered within three hotspots in the helical and kinase domains of p110α: E542K, E545K and H1047R, which represent about 80% of the mutations observed, and confirmed to be oncogenic gain-of-function mutations. Based on these findings cancer-specific mutants of p110α appear to be ideal targets for drug development and p110α specific inhibitors, such as NVP-BYL719, could then have potential anti-cancer activity without causing the potential side effects that could be expected from interference with other Class I PI3K isoforms or other members of the PIKK family. NVP-BYL719 is best described as a PI3Kalpha inhibitor as in biochemical assays, it inhibits p110α as well as p110α most common somatic mutations (IC50=5 nM) much more potently than p110α and ≤ and has weak or no activity against p110α, Vps34 and mTOR and is selective against a wide range of protein kinases (> 50-fold). The potency and selectivity profile of NVP-BYL719 is confirmed at the cellular level, is correlated with inhibition of various PI3K/Akt downstream signaling pathway components and is associated with anti-proliferation of breast cancer cell lines harboring PIK3CA mutations. In vivo, NVP-BYL719 shows dose and time-dependent inhibition of the PI3K/Akt pathway which correlates with compound exposure and is associated with good tolerability and significant dose-dependent anti-tumor efficacy in PIK3CA mutant tumor xenograft models in rodents. Moreover, plasma insulin levels are significantly increased while blood glucose levels remained normal at all tested doses and time points indicating on-target effects of NVP-BYL719 on the regulation of metabolism. Overall, as a PI3Kalpha inhibitor, NVP-BYL719 has good drug-like and pharmacological properties and presents all the characteristics required for its ongoing Phase I clinical development in adult patients with advanced solid malignancies whose tumors have an alteration of the PIK3CA gene.

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 3748. doi:1538-7445.AM2012-3748
Abstract 3807: Regulation of pancreatic, gliosarcoma and non-small cell lung cancer via CPI-613, a novel anticancer therapeutic agent
Authors: Perera Candida N. , Rodriguez Robert , Shorr Robert
Published: August 2012

While the novel anticancer agent CPI-613, currently in clinical trials, is primarily known to affect multiple cancer cell energy metabolic processes and pathways, here we demonstrate that CPI-613 also shows cancer-cell-cycle-specific effects on BxPC3 (human pancreatic) cancer cells, SF539 (human gliosarcoma) cells, and H460 (human non-small cell lung cancer) cells but not on non-transformed NIH3T3 (murine fibroblast) cells. Specifically, gene microarray data demonstrates that CPI-613 affects signal transduction pathways and genes related to cell cycle maintenance and progression as well as energetic metabolic processes and pathways. The total RNA production was also significantly reduced in cancer cells treated with CPI-613 compared to non treated controls. Multiple cyclins, p27, p19, and CDK2 are specifically noted to be downregulated in cancer cells treated with this drug, thereby halting the cell cycle at multiple points. Further study of this phenomenon may lead to additional indications for CPI-613 treatment.

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 3807. doi:1538-7445.AM2012-3807
Abstract 3821: Interaction and cross-resistance of cisplatin and pemetrexed in malignant pleural mesothelioma cell lines
Authors: Kitazono Miyako , Takiguch Yuichi , Kitazono Satoru , Ashinuma Hironori , Kitamura Atsushi , Tada Yuji , Kurosu Katsushi , Sakaida Emiko , Sekine Ikuo , Tanabe Nobuhiro , Tagawa Masatoshi , Tatsumi Koichiro
Published: August 2012

Background: Malignant pleural mesothelioma (MPM) is one of the most lethal cancers with a rapidly increasing incidence worldwide. Although cisplatin and pemetrexed are recognized as key drugs, and their combination chemotherapy is a standard therapy for MPM, their drug-to-drug interactions, cross-resistance, and resistance mechanisms are not well understood. Methods: The interaction between cisplatin and pemetrexed was evaluated by colonogenic assays followed by isobologram analysis in 4 human MPM cell lines. The cell lines were exposed to the agents using a stepwise dose-escalation method to establish drug-resistant sublines. Thymidylate synthase (TS) mRNA expression was evaluated by RT-PCR, and gene expression profiles were assessed by cDNA microarray analysis and gene ontology analysis using Ingenuity Pathway Analisis (IPA) in the drug-resistant sublines. Results: Cisplatin and pemetrexed had synergistic effects in 3 cell lines and an additive effect in the fourth cell line. The former 3 cell lines showed similar sensitivity to pemetrexed in the parental cells and their cisplatin-resistant sublines, whereas the fourth cell line exhibited cross-resistance. In contrast, cisplatin had diverse effects on pemetrexed-resistant sublines. High TS expression did not correlate with natural pemetrexed resistance and its elevatedexpression correlated with acquired pemetrexed resistance in 2 sublines. Microarray analysis disclosed that the genes which related to “cellular development”,” small molecule biochemistry,” “cellular movement,” “cell death, and “cellular growth and proliferation” affected drug-resistant mechanisms deeply, and that this tendency was common to cisplatin-resistant sublines and pemetrexed-resistant sublines. Conclusion: Cisplatin and pemetrexed showed synergistic activity and no cross-resistance in 3 of the 4 MPM cell lines, suggesting the clinical relevance of their combination chemotherapy. TS expression did not necessarily correlate with pemetrexed resistance. Multiple mechanisms of molecular and cellular functions may underlie acquired resistance to cisplatin and pemetrexed in MPM.

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 3821. doi:1538-7445.AM2012-3821
Abstract 3974: A comprehensive resequence-analysis of 250kb region of 8q24 in Africans
Authors: Chung Charles C. , Hsing Ann W. , Yeager Meredith , Yeboah Edward , Biritwum Richard , Tettey Yao , Adjei Andrew , Marzo Angelo De , Netto George J. , Isaacs William B. , Isaacs Sarah D. , Boland Joseph , Chanock Stephen J.
Published: August 2012

To date, genome-wide association studies (GWAS) have identified more than 45 prostate cancer susceptibility variants, of which at least 5 independent loci were identified within a 654kb region on 8q24. This region also harbors additional loci associated with cancers of the breast, colon, bladder, and chronic lymphocytic leukemia. Previously, the linkage disequilibrium (LD) pattern and recombination hotspots (chr8:128050768-128300801, hg19) defined a 250kb span (region 2) harboring multiple prostate cancer susceptibility loci identified in multiple distinct populations, as well as a locus rs2456449 associated with chronic lymphocytic leukemia in Europeans. Because GWAS identify genetic markers, fine-mapping using sequence analysis in diverse populations is necessary for defining the optimal variants for biological follow-up. Sequence analysis in populations of distinct ancestry can provide important insights into the differences of LD patterns and thus narrow down high interest variants. In the present study, we have resequenced the region in 125 men of African ancestry, which included 78 individuals from a population-based study in Ghana and 47 African-American individuals from the Johns Hopkins Hospital. Upon comparison with 1000 Genomes data (Oct 2011 release), we have identified 365 novel loci and additional surrogates of known susceptibility loci which could be important in establishing priorities for future functional work, designed to explain the biological basis of the association signal for both prostate cancer and perhaps, chronic lymphocytic leukemia.

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 3974. doi:1538-7445.AM2012-3974
Abstract 4017: Gene silencing of EREG mediated by DNA methylation and histone modification in human gastric cancers
Authors: Yun Jiyeon , Song Sang-Hyun , Park Jinah , Han Sae-Won , Oh Do-Youn , Im Seock-Ah , Bang Yung-Jue , Kim Tae-You
Published: August 2012

Epiregulin (EREG), a ligand of the epidermal growth factor receptor (EGFR), induces cell growth by binding to the EGFR. Expression of EREG affects sensitivity to cetuximab a chimeric monoclonal antibody that inhibits the EGFR signaling pathway. The mechanism through which EREG is regulated is largely unknown, but a methyl-array study performed by our group revealed that EREG is methylated in gastric cancer cells. In the present study, we found that EREG gene expression was low in seven out of 11 gastric cancer cells and this down-regulation was mediated by aberrant CpG methylation of the EREG promoter. Treatment with 5-aza-CdR restored EREG expression and demethylated the CpG sites in the EREG promoter. Compared to DNMT1, knockdown of DNMT3b significantly increased the expression of EREG mRNA and led to the demethylation of specific CpG sites in the EREG promoter, suggesting that DNMT3b primarily regulates the CpG methylation and silencing of EREG gene. EREG methylation was observed in 30% (4/13) of human primary gastric tumor tissues. In addition to DNA methylation, results from a ChIP assay demonstrated that transcriptional levels of EREG were associated with the enrichment of active histone markers (H3K4me3 and AcH3) and of a repressive marker (H3K27me2). Treatment with 5-aza-CdR dynamically increased the low occupancy of H3K4me3 and AcH3, while decreasing the high enrichment of H3K27me2, indicating that dynamic histone modifications contribute to EREG regulation in addition to DNA methylation. Lastly, the combination of 5-aza-CdR and cetuximab exerted a synergistic anti-proliferative effect on gastric cancer cells. Taken together, the results of our study demonstrated for the first time that EREG is epigenetically silenced in gastric cancer cells by aberrant DNA methylation and histone modification.

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 4017. doi:1538-7445.AM2012-4017
Abstract 4085: The roles of HDACs in chromatin remodelling and response to chemotherapy in cancer
Authors: Huang Rui , Langdon Simon P. , Harrison David J. , Faratian Dana
Published: August 2012

Background: Chromatin is dynamic in higher-order structure in response to extracellular and environmental signals. We observed nuclear morphological changes in clinical cancer tissues after chemotherapy. Since chromatin structure dictates gene expression, and therefore function, further investigation of this phenomenon may help us to better understand therapeutic responses. We hypothesise that nuclear morphological changes in cancer in response to DNA-damage by chemotherapy are mediated by histone deacetylases (HDACs). Methods: Ovarian cancer cell lines PEO1/PEO4 (platinum sensitive/resistant) were selected as in vitro models, and primary ovarian cancer xenografts OV1002 and HOX424 as in vivo models. Expression levels of HDACs and heterochromatin protein 1 (HP1) were screened by reverse phase protein array (RPPA) and western blot after treatment with cisplatin. Immunofluorescence imaging was undertaken using confocal microscopy and nuclear texture was measured in Image J using GLCM texture analysis plugin. 38 ovarian cancer patient and 175 xenograft samples were assessed for HDAC and HP1 expression in response to chemotherapy by quantitative immunofluorescence. HDAC2 expression was modulated by interfering RNAs (siRNA). Results: We demonstrate nuclear morphological changes in clinical tumours, xenografts, and cell lines in response to platinum chemotherapy. HDACs and HP1 isoforms showed differential expression in a panel of 25 ovarian cancer cell lines associated with response to chemotherapy with increased expression in treated or resistant lines. Expression of HDACs increased in PEO1 cells treated with cisplatin in a time-dependent fashion. This was accompanied by quantifiable changes in nuclear texture (increased heterogeneity), and high expression of HP1s at early time point (4-24h). The proliferation of PEO1 cells was inhibited and HP1 protein expression decreased after HDAC2 knockdown. In clinical specimens, HDAC8 and HP1 gamma expression significantly increased after chemotherapy, and class I HDAC (1, 2, and 8) and HP1 expression were increased after carboplatin treatment in carboplatin-sensitive xenografts. Chromatin conformation, DNA damage response, and cell cycle progression showed sequential changes over time with carboplatin treatment. Conclusion: These results demonstrate alterations in chromatin structure after chemotherapy, and implicate the role of class I HDACs in higher order chromatin changes and the DNA damage response in ovarian cancer in vitro and in vivo.

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 4085. doi:1538-7445.AM2012-4085
Abstract 4094: Identification of novel breast cancer methylation biomarkers by global demethylation, cDNA microarray, and quantitative methylation analysis
Authors: Ye Chuanzhong , Hu Zhijian , Courtney Regina , Zheng Wei , Cai Qiuyin
Published: August 2012

Aberrant DNA methylation is commonly found in breast cancer. Hypermethylation of CpG islands located in promoter regions of genes may result in translational gene silencing and thus play an important role in carcinogenesis. It has been documented that multiple genes involved in cell cycle regulation, apoptosis, DNA repair, hormone regulation, cell adhesion and invasion, angiogenesis, and cellular growth-inhibitory signaling pathways are hypermethylated in breast cancer. To identify additional hypermethylated genes, we conducted a global demethylation experiment using breast cancer cell lines, followed by gene expression microarray and DNA methylation analyses. Breast cancer MCF-7 cells were treated with 5-aza-2′-deoxycytidine (5-aza-dC) and trichostatin A (TSA). Gene expression profiles between 5-aza-dC/TSA treated and untreated cells were compared using the Affymetrix GeneChip Human Genome U133 Plus 2.0 Array. Expression levels of 195 genes were up-regulated at least two-fold by demethylation treatment of the MCF-7 cells. Expression levels of 16 cancer-related genes were selected for confirmation in six additional breast cancer cell lines using quantitative real-time PCR. Expression of 13 of these genes (APLP1, CARHSP1, CDKN2D, CKMT1A, FSCN1, GPX3, HBEGF, HIC2, HSPA2, NOV, S100A6, SERPINI1, and ZNF238) was confirmed to be significantly increased after 5-aza-dC/TSA treatment. Promoter methylation status of these 13 genes was examined in seven breast cancer cell lines using Sequenom MassARRAY quantitative methylation analysis. Promoter CpG island methylation of 6 genes was observed in all 7 breast cancer cell lines. The ZNF238 and HSPA2 genes had the most methylated CpG sites (each has 11 methylated CpG sites) and highest percentage of methylation in the promoter region tested in the study. In summary, we identified promoter hypermethylation in 6 cancer-related genes, including ZNF238 and HSPA2, in breast cancer cell lines. These genes may play a role in breast carcinogenesis. Further studies using human breast cancer samples are warranted to confirm these findings.

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 4094. doi:1538-7445.AM2012-4094
Abstract 4111: A transcriptional variant of the LC3A gene is involved in autophagy and frequently inactivated in human cancers
Authors: Yamamoto Shinsuke , Inoue Jun , Bai Hua , Kawano Tatsuyuki , Inazawa Johji
Published: August 2012

Microtubule-associated protein 1 light chain 3 (MAP1LC3: LC3) has an important role in autophagy. The human LC3 gene family has five members, LC3A (variant-1: v1 and –2: v2), LC3B, LC3B2, and LC3C. While a form of LC3B modified by phosphatidylethanolamine (PE) (form-II) is localized in autophagosomes, it is not clear whether other LC3 proteins also function in autophagy. Here, we examined the association between autophagy and human LC3 proteins during starvation- or p53-induced autophagy in Saos-2 cells. In an analysis of the intracellular distribution of each LC3 protein fused with GFP, GFP-LC3Av1 was frequently localized in autophagosomes with a punctate pattern, similar to GFP-LC3B. Further, endogenous LC3Av1 generated form-II and mostly localized in LC3B-positive autophagosomes during the induced autophagy. Interestingly, LC3Av1, not LC3B, was frequently inactivated at the transcriptional level in various human cancer cell lines (111/244 cell lines, 45.5%) and its inactivation was due to aberrant DNA methylation in esophageal squamous cell carcinoma (ESCC) cell lines and primary tumors. Restoration of LC3Av1 expression in KYSE170 cells, an LC3Av1-inactivated ESCC cell line, showed the inhibition of tumor growth in vivo. These results suggest that LC3Av1, not only LC3B, functions in autophagy and further, LC3Av1 may be crucial in carcinogenesis.

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 4111. doi:1538-7445.AM2012-4111
Abstract 4117: Increased pancreatic adipocyte hypertrophy in EL-Kras/PEDF null mice with versus without pancreatic cancer
Authors: Samiei Arash , Fitchev Philip S. , Bentrem David J. , Melstrom Laleh G. , Adrian Kevin , Cornwell Mona L. , Crawford Susan E. , Grippo Paul J.
Published: August 2012

Understanding non-parenchymal contributions to disease etiology and factors that assess risk and prognosis are currently key points of interest in pancreatic cancer research. One such focus is in regards to fat, where obesity and increased visceral fat enhance risk and predict worse prognosis for pancreatic cancer patients. Pigment epithelium-derived factor (PEDF), initially identified for its potent anti-angiogenic activity, has been recently implicated in metabolism and adipogenesis, and loss of PEDF in mice promotes pancreatic hyperplasia and visceral obesity. In an attempt to create a model of pancreatic cancer that emulates metabolic features related to fat content, we generated PEDF knockout mice with KrasG12D-induced pancreatic neoplasia, where oncogenic Kras can also induce adipogenesis (typically observed as lipoatrophy). We have recently shown that EL-KrasG12D/PEDF null mice developed invasive pancreatic cancer associated with increased peripancreatic fat with adipocyte hypertrophy and pancreatic steatosis. Indeed, the stroma within the pancreas of these mice demonstrated higher levels of tail interacting protein 47 (TIP47, Perilipin 3) and adipose differentiation-related protein (ADRP, Perilipin 2), two lipid droplet associated proteins. In this study, we expanded upon this work to demonstrate that in most EL-Kras/PEDF null mice, there appeared to be greater number of neoplastic lesions near neighboring fat stores. In addition, there was a significant increase in the size of adipocytes (greater adipocyte hypertrophy) in EL-Kras/PEDF null mice with invasive cancer as opposed to age-matched mice with an identical genotype without the presence of cancer. Despite increased adipocytes in mice with cancer, there was no significant difference in overall body weight between these cohorts of animals. Future work aims at identifying if neoplastic lesions near adipocytes have a greater proliferative index and hence an increase in size. Ultimately, we hope to demonstrate that larger and more numerous adipocytes contribute to the development of pancreatic cancer. These data highlight the importance of lipid metabolism in the tumor microenvironment and identify PEDF as a critical negative regulator of both adiposity and tumor invasion in the pancreas, with implications that PEDF's effect on fat stores may induce cellular events leading to invasive 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 4117. doi:1538-7445.AM2012-4117
Abstract 4119: High-throughput proteomics reveals that enzymes of the ketogenic pathway are upregulated during prostate cancer progression
Authors: Saraon Punit , Cretu Daniela , Jarvi Keith , Diamandis Eleftherios P.
Published: August 2012

Prostate cancer is the most common malignancy and the second leading cause of cancer related deaths in men. One common treatment is androgen-deprivation therapy, which reduces symptoms in most patients. However, over time, patients develop tumours that are androgen-independent and ultimately fatal. The mechanisms that cause this transition remain largely unknown, and as a result, there are no effective treatments against androgen-independent prostate cancer. As a model platform, we used the LNCaP cell line, and its androgen independent derivative, LNCaP-SF. By using stable isotope labelling with amino acids in cell culture (SILAC) coupled to mass spectrometry, we assessed the differential global protein expression between the two cell lines. Our proteomic analysis resulted in the quantification of 3355 proteins, in total. Bioinformatic prioritization resulted in 42 up-regulated and 46 down-regulated proteins in LNCaP-SF cells, compared to LNCaP cells. Our top candidate was HMGCS2, an enzyme involved in ketogenesis, was found to be 9-fold elevated in LNCaP-SF cells, based on peptide ratios. After analyzing the remaining enzymes of this pathway (ACAT1, BDH1, HMGCL, OXCT1), we observed increased expression of these proteins in the LNCaP-SF cells. This was further verified using western blotting, indicating the importance of this pathway during the progression of prostate cancer to androgen-independence. To determine whether these enzymes are up-regulated in clinical samples, we performed qPCR analysis on human prostate cancer tissues, from which we observed significantly increased transcript levels of HMGCS2 (p<0.05), OXCT1 (P<0.05), ACAT1 (p<0.001), and BDH1 (p<0.001). In addition, the protein expression of all five ketogenic pathway enzymes was elevated in high grade prostate cancer (Gleason Grade >8) based on immunohistochemistry analysis. ACAT1 displayed the most prominent protein expression patterns, as it exhibited very minimal staining in normal samples, moderate levels in low grade cancer, and high expression during high grade disease. Further assessment of ACAT1 expression demonstrated significantly greater ACAT1 expression in bone metastatic lesions (P<0.001). Altogether, our results indicate that enzymes belonging to the ketogenic pathway become up-regulated during high grade prostate cancer, and could serve as potential biomarkers for diagnosis of high grade 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 4119. doi:1538-7445.AM2012-4119
Abstract 4120: UDP-Glucuronosyltransferase 1 (UGT1A1) down-regulation correlates to menopausal status and stage of disease in human breast cancer tissues
Authors: Starlard-Davenport Athena , Word Beverly R. , Lyn-Cook Beverly D.
Published: August 2012

Estrogen metabolism, catalyzed by UGTs, is a major drug-metabolic pathway that results in the complete inactivation of estrogens and their hydroxylated metabolites. Alterations in UGTs, resulting in decreased UGT expression and glucuronidation activity towards estrogens and their metabolites, has been suggested to play a potential role in breast cancer risk. The purpose of this study was to: 1) compare the mRNA expression levels of UGTs responsible for conjugating estrogens in human breast cancers and normal breast tissues from women; 2) compare UGT1A1 mRNA expression to tumor stage, ER status, ethnicity, and menopausal status in a group of human breast tumors and normal breast tissues, and 3) investigate the association between variations in the number of TA repeats in the promoter region of UGT1A1 to gene expression. Quantification of UGT mRNA in breast tissues revealed that UGT1A4, UGT1A9, UGT1A10, and UGT2B7 mRNA levels were decreased in breast cancers as compared to normal breast tissues. UGT1A1 mRNA levels were also significantly decreased in breast cancers (N = 17) as compared to normal breast tissues (N = 30) (p = 0.02). UGT1A1 down-regulation strongly correlated with menopausal status (premenopausal vs. postmenopausal; p = 0.04) and stage of breast disease (p = 0.01). This may account for variations in response to chemotherapy used for the treatment of more aggressive breast cancers. UGT1A1 mRNA was also decreased in breast tumors as compared to normal breast tissues from both African American and European American women. We postulated that the decreased levels of UGT1A1 mRNA in breast cancers may be due to a genetic variant in the promoter of UGT1A1. In all UGT1A1 genotypes observed in our study, the mean UGT1A1 mRNA expression levels was significantly decreased among breast cancer cases as compared to controls (p = 0.04). Our research findings suggest that further investigations are necessary to determine the role of UGT1A1 in breast carcinogenesis.

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 4120. doi:1538-7445.AM2012-4120
Abstract 4141: The role of microRNA in gastric cancer
Authors: Li Jianfang , Yu Beiqin , Feng runhua , Su liping , Zhu zhenggang , Liu bingya
Published: August 2012

Objectives: To expore miRNA expression pattern in gastric cancer and investigate the role of miRNAs in the tumorigenesis of gastric cancer. Methods: We globally analyzed the miRNA expression profile in 9 gastric cancer cell lines and 6 normal gastric mucosa and the tumor tissues and its corespending adjacent normal tisuues of 30 patients through miRNA microarray. The differential expression of miRNAs from miRNA microarray were confirmed by qRT-PCR. Then, we extended our assay to sixty paired gastric cancer tissues and the relationship between miR-126 expression level and clinicopatholoic variables was explored. The specific miR-126 precursor or miR-126 expression vector were transfected into gastric cancer cell line SGC-7901 to up-regulate miR-126 expression and its biological effects on SGC-7901 cells were investigated. Finally, the target gene of miR-126 was predicted by bioimformatic method and validated by luciferase reportor system. Results: found that 17 miRNAs were up-regulated in gastric cancer cell lines and 146 miRNAs were down-regulated compared with normal gastric mucosa. Then we performed quantitative real-time PCR of 15 up-regulated miRNAs and 26 logRatio < –5.0 down-regulated miRNAs in gastric cancer cell lines and gastric cancer tissues for further analysis. The coincidence of microarray data and qPCR results was in an acceptable range and 15 miRNAs were finally selected. These candidate miRNAs were associated with gastric cancer clinicopathology in different degree. Meanwhile, high expression of hsa-miR-93 and hsa-miR-409-3p were found to predict poor survival (median, 16 months vs 40 months, LogRank p < 0.05). we show that miR-126 is significantly down-regulated in gastric cancer tissues and associated with clinicopathological features such as tumor size, lymph node metastasis, local invasion and TNM stage. Ectopic expression of miR-126 in SGC-7901 gastic cancer cells potently inhibits cell growth by inducing cell cycle arrest at G1 phase, migration and invasion in vitro and tumorigenicity in vivo. Mechanistically, we identify adaptor protein Crk as a target of miR-126. Taken together, our findings demonstrate miR-126 may function as a tumor suppressor in gastric cancer through regulation of genes such as Crk. Conclusions: These findings may suggest vital roles of miRNAs in huamn gastric cancer, and provide clues for understanding the molecular basis of miRNAs in various biological processes.

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 4141. doi:1538-7445.AM2012-4141
Abstract 4143: microRNA-874 as a tumor suppressor in maxillary sinus squamous cell carcinoma based on microRNA expression signature
Authors: Hanazawa Toyoyuki , Nohata Nijiro , Kinoshita Takashi , Kikkawa Naoko , Fuse Miki , Chiyomaru Takeshi , Yoshino Hirofumi , Enokida Hideki , Nakagawa Masayuki , Okamoto Yoshitaka , Seki Naohiko
Published: August 2012

(BACKGROUND) Maxillary sinus squamous cell carcinoma (MSSCC) comprises 2-3% of all cancers of head and neck tumor and the annual incidence rate is 0.5-1.0 per 100,000 populations. After introduction of multimodality treatment comprising radiation therapy along with concomitant intra-arterial chemotherapy, rates of local control was improved. However the prognosis of advanced MSSCC is still worse. The 5-years survival rate of T4 tumors is 50% around. Local recurrence is the most common cause of treatment failure and death. Greater understanding of the molecular oncogenic network in MSSCC could help improve diagnosis, therapy, and prevention of the disease. No studies have been carried out for the purpose of identifying specific microRNA (miRNA) alterations in MSSCC. In this study, we focused on the functional siginificance of the most downregulated miRNA in MSSCC on the basis of miRNA expression signature. (METHODS) We used PCR-based methods to investigate the downregulated miRNAs in clinical specimens of MSSCC. Genome-wide gene expression analysis was performed to identify the molecular networks of microRNA-874 (miR-874) by microarray technique. Cell proliferation and invasion assays were performed to investigate the functional significance of miR-874 and its target genes in MSSCC cell lines. (RESULTS) Our miRNA signature identified that 23 miRNAs were significantly reduced in cancer cells. We focused on miR-874 as the most downregulated novel miRNA in our analysis. Ectopic miR-874 overexpression showed potential tumour suppressive functions such as inhibition of cancer cell proliferation and invasion. A molecular target search of miR-874 revealed that protein phosphatase 1, catalytic subunit, alpha isozyme (PPP1CA), proteasomal ATPase-associated factor 1 (PAAF1) and trans-golgi network protein 2 (TGOLN2) were regulated by miR-874. Overexpression of these genes was observed in MSSCC clinical specimens and each gene expression was inversely correlated with miR-874 expression. Moreover, silencing of the PPP1CA gene significantly inhibited cancer cell proliferation and invasion. (CONCLUSION) The downregulation of miR-874 was a frequent event in MSSCC, which suggests that miR-874 functions as a tumour suppressive miRNA, directly regulating PPP1CA that has a potential role of an oncogene. The identification of novel miR-874-regulated cancer network could provide new insights into potential molecular mechanisms of MSSCC oncogenesis.

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 4143. doi:1538-7445.AM2012-4143