bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1505: Stroma-mediated DNA damage resistance of human breast cancer
Authors: Boelens Mirjam C. , Wu Tony J. , Yoon Taewon , Azzam Diana , Slingerland Joyce M. , Minn Andy J.
Published: August 2012

Chemotherapy and radiation are often employed to decrease breast cancer deaths. However, patients with metastatic disease invariably manifest resistance to chemotherapy and/or radiation, ultimately causing breast cancer deaths due to ineffective treatment. We have defined a gene expression signature, the interferon-related DNA damage resistance signature (IRDS), that is highly associated with radiation and chemotherapy resistance of breast cancer in both cell lines and patients. Interestingly, IRDS-mediated resistance in experimental models appears to be much greater in vivo than in vitro, suggesting a potential contribution of the tumor microenvironment. To address the question of whether the tumor microenvironment plays a role in IRDS-mediated radioresistance, we investigated the influence of heterotypic interactions between breast cancer and stromal cells on IRDS expression. We found that breast cancer cell lines primarily of the basal subtype increase IRDS expression after tumor-stroma interaction, resulting in enhanced resistance to radiation and chemotherapy. This increase in IRDS and DNA damage resistance depends on STAT1, a member and transcriptional regulator of the IRDS. Tumor-stroma interaction also leads to induction of a population of breast cancer cells with properties of breast cancer stem-like cells (BCSC). Evaluation of a tumor-stroma extracellular interactome revealed that a stroma-directed NOTCH signaling pathway can cooperate with STAT1 signaling to regulate common target genes. STAT1 and NOTCH signaling direct the expansion and/or survival of BCSC, an inherently DNA damage resistant population. Using available primary breast cancer data sets, a similar activation of NOTCH signaling is observed, as well as transcriptomic activation of the NOTCH pathway in breast cancer. Importantly, a marker for NOTCH signaling cooperates with the IRDS to identify breast cancer patients likely to fail adjuvant chemotherapy. The ability of gamma secretase inhibitors to inhibit both stroma-mediated expansion of BCSC and DNA damage resistance highlights the therapeutic potential of this class of targeted agents for breast cancers that express the IRDS. In conclusion, our data suggests that stroma can regulate DNA damage resistant BCSC populations in a subset of basal breast cancers through STAT1 and NOTCH signaling.

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 1505. doi:1538-7445.AM2012-1505
Abstract 1508: TNF-receptor 2 plays a critical role in liver metastasis by regulating sinusoidal endothelial VCAM-1 expression, LY6G+ leukocyte recruitment and transendothelial migration
Authors: Ham Boram , Auguste Patrick , Evrard Maximilien , Wang Ni , Lu Yifan , Brodt Pnina
Published: August 2012

The hepatic microenvironment can play an important role in promoting liver metastasis. We and others have shown that when metastatic carcinoma cells enter the liver, a rapid inflammatory response mediated by TNF-α is triggered, enabling tumor transendothelial migration and metastasis. TNF-α binds to the cell surface through two receptors; the p55/p60 TNFR1 and the p75/p80 TNFR2. To elucidate the roles of these receptors in the inflammatory cascade and in liver colonization by tumor cells, we used mice with tnfr1, tnfr2 and combined tnfr1/tnfr2 gene deficiencies and investigated parameters of the host response and the outcome of metastasis in these mice using the highly metastatic mouse colon carcinoma MC-38 and lung carcinoma H-59 cells. We found that experimental liver metastasis following intrasplenic/portal inoculation of the tumor cells was markedly reduced in TNFR2−/− and even further in TNFR1−/−/TNFR2−/- female mice as compared to wild-type controls but no reduction was observed in TNFR1−/− mice. To identify the underlying mechanism(s), we investigated changes in the liver microenvironment following tumor inoculation using a combination of immunohistochemistry, confocal microscopy, qRT-PCR, and cytokine/chemokines profiling. We found that while in wild-type and TNFR1−/- mice, VCAM-1 expression on the sinusoidal endothelium was significantly upregulated within 16 hr post tumor injection, it was unchanged in TNFR2−/− and double negative female mice. In addition, qRT-PCR analysis revealed that the production of the neutrophil chemokine CXCL1, while upregulated in control mice, was suppressed in TNFR2−/− mice. These changes were associated with a parallel decrease in Ly6G+ neutrophil recruitment into extravascular, pro-metastatic niches 16-48 hr post tumor inoculation. Interestingly, these reductions were not observed in male TNFR2−/− mice and correspondingly, their metastatic burden was not reduced relative to control mice. Taken together, the results suggest that TNFR2 plays a critical and gender-specific role in Ly6G+ cell recruitment into the tumor-microenvironment by regulating sinusoidal endothelial VCAM-1 expression and chemokine production. In turn, the recruitment of these cells into extravascular pro-metastatic niches appears to promote liver metastasis. Supported by grant MOP-80201 from the Canadian Institute for Health Research. (to PB) and by a McGill Integrated Cancer Research Training Program fellowship (to BH).

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 1508. doi:1538-7445.AM2012-1508
Abstract 1509: Modulation of stromal reaction by PDGF-R tyrosine kinase inhibitor in an orthotopic mice model of gastric carcinoma
Authors: Kitadai Yasuhiko , Onoyama Mieko , Shinagawa Kei , Ohnishi Mayu , Ohara Eiji , Tanaka Shinji , Yasui Wataru , Chayama Kazuaki
Published: August 2012

Recent studies in molecular and cellular biology have shown that tumor growth and metastasis are not determined by cancer cells alone but also by a variety of stromal cells. Many human tumors secrete platelet-derived growth factor (PDGF) ligands, and PDGF receptors (PDGF-Rs) are expressed by various stromal cell populations, including carcinoma-associated fibroblasts (CAFs). We reported recently that, in a mice model of colon cancer, bone marrow-derived mesenchymal stem cells (MSCs) traveled to tumor stroma, where they differentiated into CAF-like cells. In the present study, we examined PDGF-B and PDGF-Rβ expression in relation to clinicopathologic features of human gastric carcinomas. We also examined the effects of PDGF-R tyrosine kinase inhibitors (imatinib, nilotinib) on tumor stroma in an orthotopic nude mouse model of human gastric carcinoma. Five gastric carcinoma cell lines and 38 surgical specimens of gastric carcinoma were used. Under culture conditions, gastric cancer cell lines expressed PDGF-B at various levels but not PDGFR-β. When cells from these lines were implanted orthotopically into the gastric wall of nude mice, cells with high PDGF-B expression resulted in tumors with abundant stroma. In contrast, cells with low PDGF-B expression resulted in medullary tumors with little stromal reaction. In surgical specimens, we found PDGF-B expression to be associated with stromal reaction. PDGF-B and PDGF-Rβ mRNA expression was significantly higher in patients with lymph node metastasis than in those without and also significantly higher in diffuse-type carcinoma than in intestinal-type carcinoma. In surgical specimens and orthotopic tumors, tumor cells expressed PDGF-B, but PDGF-Rβ was expressed predominantly by stromal cells, including CAFs, pericytes, and lymphatic endothelial cells. Treatment with PDGF-R tyrosine kinase inhibitors did not inhibit tumor growth but did significantly decrease the stromal reaction, lymphatic invasion, lymphatic vessel area, and pericyte coverage of tumor microvessels. In addition, tumor tropism of MSCs was also inhibited by treatment with PDGF-R inhibitors in vivo and in vitro. The PDGF/PDGF-R signaling pathway appears to regulate cancer-stromal cell interaction, and target molecule-based inhibition of the stromal reaction may hold promise as an effective anti-tumor therapy.

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 1509. doi:1538-7445.AM2012-1509
Abstract 151: Advancing pathway analysis using bioluminescent reporters
Authors: Robers Matthew B. , Binkowski Brock , Karassina Natasha , Stecha Pete , Eggers Chris , Cheng Jey , Zimmerman Kris , Fan Frank , Cong Mei
Published: August 2012

To enable investigation of key cellular signaling pathways, Promega has developed a portfolio of bioluminescent reporter gene assays using Firefly and Renilla luciferases. In combination with best-in-class luciferase detection reagents, these genetic reporter systems enable interrogation of important cellular responses involved in cancer, inflammation, and CNS disease. To address specialized customer needs in our industrial and research markets, Promega has a new custom assay service team dedicated to applying these enabling technologies through strategic external research collaborations. The performance of this technology portfolio is presented, including novel applications of luciferase reporters to interrogation of cytokine, stress, and toxicity pathway responses.

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 151. doi:1538-7445.AM2012-151
Abstract 1516: HB-EGF and PDGF mediate reciprocal interactions of carcinoma cells with cancer-associated fibroblasts to support progression of uterine cervical cancers
Authors: Murata Takuya , Enomoto Takayuki , Ueda Yutaka , Yoshino Kiyoshi , Yagi Shigeo , Hoffman Robert M. , Mizushima Hiroto , Kimura Tadashi , Mekada Eisuke
Published: August 2012

Tumor stroma drives the growth and progression of cancers. A heparin-binding epidermal growth factor-like growth factor, HB-EGF, is an EGF receptor ligand that stimulates cell growth in an autocrine or paracrine fashion. While elevated expression of HB-EGF in cancer cells and its contribution to tumor progression are well documented, the effects of HB-EGF expression in the tumor stroma have not been clarified. Here, we show that HB-EGF is expressed in stromal fibroblasts where it promotes tumor cell proliferation. In uterine cervical cancers, HB-EGF was detected immunohistochemically in the stroma proximal to the cancer epithelium. Proliferation of cervical cancer cells in vitro was enhanced by coculture with fibroblasts isolated from tumor tissues of patients with cervical cancer. Inhibition of HB-EGF function or treatment with platelet-derived growth factor (PDGF) inhibitors abrogated cancer cell growth enhanced by cervical cancer-associated fibroblast (CCF) coculture. Furthermore, tumor formation in a mouse xenograft model was enhanced by cotransplantation of CCF or mouse embryonic fibroblasts but not with embryonic fibroblasts from HB-EGF-deficient mice. Conversely, conditioned medium from cancer cells induced HB-EGF expression in CCF and mechanistic investigations established that PDGF was the primary factor responsible. Together, our findings indicate that HB-EGF and PDGF reciprocally mediate the interaction of cancer cells with cancer-associated fibroblasts, promoting cancer cell proliferation in a paracrine manner that has implications for novel combinatorial 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 1516. doi:1538-7445.AM2012-1516
Abstract 1558: Innovative biotherapy for brain tumors: Myxoma virus accelerates NK clearance of malignant gliomas
Authors: Ogbomo Henry , Lun Xueqing , Zhang Jiqing , Zemp Franz J. , Mcfadden Grant , Mody Christopher H. , Forsyth Peter A.
Published: August 2012

Innovative biotherapeutic approaches for experimental malignant gliomas (MGs) and brain tumor stem cells (BTSCs) include using oncolytic viruses such as Myxoma Virus (Myxv) or immune cells such as Natural Killer (NK) cells. In this study, we combined the individual strengths of using NK cells and Myxv to treat MGs with a view of overcoming the potential limitations posed when each is used as monotherapy. All MGs (U87, U251) and BTSCs (25EF and 48EF) investigated expressed varying levels of NK ligands including inhibitory MHC-I, activating ULBP1-3, MICA/B, and co-activating nectin-2, poliovirus receptor. Infection of MGs and BTSCs with Myxv resulted in the downregulation of MHC-I expression both on the cell surface and intracellularly. No effect was observed on the expression of NK activating ligands except for the downregulation of nectin-2. The downregulation of MHC-I and nectin-2 by Myxv was specifically mediated by M153 gene of Myxv as loss of M153 restored MHC-I and nectin-2 expression. Subsequently, NK cell degranulation and killing of MGs was enhanced in Myxv-infected cells. Loss of M153 inhibited NK degranulation and lysis of MGs. In vivo, using luciferase-expressing U87 cells in a mouse intracranial model, Myxv accelerated tumor size reduction/clearance by NK cell lysis. Combined intratumoral treatment with Myxv and NK of established U87 tumor accelerated tumor clearance when compared with single treatment with Myxv or NK. Tumor in 66% of mice (4 out of 6 mice) were cleared or significantly reduced within 14 days following combination treatment with Myxv and NK. No significant effect was observed in Myxv or NK singly-treated mice within the same time frame. Clearance of tumors was only first observed in 50% (2 out of 4) of Myxv-treated mice after 25 days Myxv treatment. In NK treated mice, the tumor size rather increased. The enhanced tumor clearance in the combined Myxv and NK treated mice was possibly due to the down-regulation of MHC-I by Myxv since combined treatment with NK cells and mutant Myxv (gene M153 which is responsible for MHC-I down-regulation was deleted) did not result in clearance of tumors.

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 1558. doi:1538-7445.AM2012-1558
Abstract 156: Screening and characterization of inhibitors of G-protein coupled receptor kinase GRK6 as potential therapeutics for multiple myeloma
Authors: Griffin Carly , Subramanian Ratheesh , Zaidi Hassan S. , Marcellus Richard , Joseph Babu , Isaac Methvin , Uehling David , Leung-Hagesteijn Chungyee , Tiedemann Rodger , Al-awar Rima
Published: August 2012

Multiple myeloma (MM) is one of the most common hematological malignancies, but current therapy options are limited to high-dose chemotherapy or high-risk stem-cell transplantation. It is clear that the development of more selective and less toxic treatments for MM is greatly needed. In a recent kinome-wide RNAi study by Tiedemann and colleagues (2010), the G-protein coupled receptor kinase-6 (GRK6) was identified as a critical kinase required for survival of MM cells. This study also suggests that MM cells, but not other cell types, are dependent on GRK6; and that gene silencing by shRNA or siRNA of GRK6, but not other GRKs, results in decreased survival. At present, the G-protein coupled receptor (GPCR) signaling mediated by GRK6 in MM cells is not well understood. Our current research aims to identify the important GPCRs phosphorylated by GRK6 and the signaling proteins/pathways implicated in survival of multiple myeloma cells. Through gene silencing techniques and expression of either the wild-type or kinase-dead form of GRK6 protein, we have determined that a functional GRK6 kinase domain is required for survival of MM cells. We have also demonstrated that the signaling pathway downstream of CXCR4 phosphorylation by GRK6 is defective in cells expressing the kinase-dead GRK6-mutant protein. This loss of signaling by the GRK6-mutant protein was observed for other GPCRs found to be important for survival of MM cells. These findings helped to validate that the kinase domain of GRK6 is a potential target for MM, and spurred the identification of small molecule kinase inhibitors of GRK6. Compounds with high potency in preliminary biochemical assays were screened against MM and non-MM cell lines to evaluate their activity and specificity in vivo. Small molecule inhibition of GRK6 kinase activity is a novel approach to the treatment of MM, as it specifically targets a protein found to be critical for survival of these cells through an unbiased RNAi study. Treatment options for patients with MM are limited and based on our preliminary findings small molecule inhibitors of GRK6 offer an alternative therapeutic approach to the treatment of MM.

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 156. doi:1538-7445.AM2012-156
Abstract 1561: Leukemia cell-derived exosomes targeted dendritic cells can induce more strong anti-leukemia response than exosomes alone
Authors: Sun Jing , Chen Linjun , Deng Xiaohui , Hao Siguo
Published: August 2012

Exosomes are the newest family number of ‘bioactive vesicles’ that play important roles in antigen presentation. Recent clinical trials about exosomes have shown minor clinical benefit. However, exosomes derived from leukemia cell lines were less studied, In this study, we investigated the biological properties and anti-leukemia immunity of leukemia cell-derived exosomes (LEX). The results showed that like other tumor cells, similarly, leukemia cells can release exosomes too. Transmission electron microscopy showed that exosomes derived from NB4 cell, a promyloblastic leukemia cell line and K562 cell, a chronic myeloid leukemia cell line were membrane vesicles with diameter about 50-100μm, and loading their specific moleculars such as RAR-α and ABL and adherent moleculars such as ICAM-1. Similarly, our data also demonstrated the presence of Hsp70 in these two leukemia cell-derived exosomes. The data from two-dimensional electrophoresis of K562 cell-derived exosomes showed that most of molecules expressing on leukemia cells were detected on their exosomes, indicating that LEX load most of proteins expressed on their original leukemia cells. Out data also demonstrated that LEX can induce anti-leukemia CTL response and LEX-targeted DC can induce more efficient anti-leukemia immunity compared with LEX alone. In conclusion, exosome-based therapies could be considered as a promising strategy to prolong disease-free survival in patients with leukemia after consolidation or hematopoietic stem cell transplantation. Note: This research work was supported by research grants from Shanghai Pujiang Project of Science and Technology Commission of Shanghai Municipality. Keywords: Exosome, leukemia cell, anti-leukemia immunity

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 1561. doi:1538-7445.AM2012-1561
Abstract 1566: Inhibition of TGF-β in tumor-draining lymph nodes can enhance the potency of dendritic cell-based vaccine immunotherapy
Authors: Teramoto Koji , Fujita Takuya , Hanaoka Jun , Tezuka Noriaki , Kontani Keiichi
Published: August 2012

Transforming growth factor-β (TGF-β), an immunosuppressive cytokine, produced in the tumor microenvironment will flow into tumor-draining lymph nodes where are primary priming sites for generation of anti-tumor immune responses, and play a critical role in suppressing anti-tumor immune responses. We focused on TGF-β-mediated immunosuppression in tumor draining lymph nodes, and examined whether local inhibition of TGF-β there could enhance the potency of dendritic cell (DC) -based vaccine immunotherapy in tumor-bearing mice. C57BL/6 mice bearing Lewis lung carcinoma (LLC1) subcutaneously were vaccinated with DCs loaded with LLC1-derived antigen. In order to inhibit TGF-β in tumor-draining lymph nodes, those mice were administered the plasmid DNA encoding the extracellular domain of TGF-β type II receptor fused to the human IgG heavy chain (TGFR DNA) near the established tumor intramuscularly. As results, the level of TGF-β in tumor-draining lymph nodes was decreased by administrations of TGFR DNA near the established tumor. In tumor-draining lymph nodes, the proliferative activity of FoxP3+ regulatory T cells was eliminated, whereas tumor antigen-specific CD8+ cells producing interferon-α were increased as compared with those in mice administered DC vaccine alone. In spleen, tumor antigen-specific cytotoxic as well as natural killer activity were augmented in mice administered DC vaccine with TGFR DNA. Subsequently, growth of the established tumor was suppressed effectively. In conclusion, inhibition of TGF-β-mediated immunosuppression in tumor-draining lymph nodes can significantly enhance the potency of DC vaccine. This animal model provides for a novel rationale with DC vaccine immunotherapy.

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 1566. doi:1538-7445.AM2012-1566
Abstract 1817: Characterisation of CCT251455, a novel, selective and highly potent Mps1 kinase inhibitor
Authors: Faisal Amir , Naud Sebastian , Schmitt Jessica , Westwood Isaac , Hayes Angela , Gurden Mark , Bavetsias Vassilios , Berry Teeara , Mak Grace , Innocenti Paolo , Cheung Jack , Sheldrake Peter , Atrash Butrus , Sun Chongbo , Matijssen Berry , Burke Rosemary , Baker Ross , McAndrew Craig , Rowlands Martin , Workman Paul , Eccles Suzanne A. , Hoelder Swen , Raynaud Florence I. , vanMontfort Rob , Blagg Julian , Linardopoulos Spiros
Published: August 2012

Monopolar spindle 1 (Mps1, also known as TTK) is a dual-specificity, cell cycle-regulated kinase required for the establishment and maintenance of the spindle assembly checkpoint during mitosis. Aneuploid tumour cells possess a weak spindle checkpoint to allow onset of anaphase and cell division. Our hypothesis is that a complete inhibition of an already weakened mitotic checkpoint of cancer cells will cause gross chromosomal abnormalities leading to aneuploid cell death. We have shown that depletion of Mps1 by siRNA induces cell death selectively in aneuploid and PTEN-deficient cancer cell lines. We have demonstrated that Mps1 depletion inhibits MAD2 localisation to the kinetochores. We have developed biochemical and cellular assays for Mps1 activity and a high throughput screening of our Institute's compound library delivered multiple hit series. Medicinal chemistry in combination with X-ray crystallography led to the development of CCT251455, a small molecule inhibitor of Mps1 kinase activity. CCT251455 selectively inhibits Mps1 kinase with an IC50 of 0.003 μM, inhibits growth of a panel of human tumour cell lines with GI50 between 0.06 - 1 μM and is particularly potent in PTEN-deficient cell lines. Cells treated with CCT251455 abrogate nocodazole-induced mitotic arrest and reduce the time spent in mitosis. Mps1-inhibited cells contain aberrant numbers of chromosomes and the majority of cells divide their chromosomes without proper alignment. CCT251455 is orally bioavailable (F = 82%) and shows modulation of biomarkers 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 1817. doi:1538-7445.AM2012-1817
Abstract 1819: A MUC1-C oncoprotein soluble decoy receptor effectively suppresses the growth of human breast cancer cells
Authors: Panchamoorthy Govind , Raina Deepak , Rehan Hala , Kharbanda Surender , Kufe Donald
Published: August 2012

The Mucin 1 (MUC1) transmembrane glycoprotein is aberrantly overexpressed by most human breast carcinomas and contributes to the malignant phenotype. MUC1 is expressed as two subunits (MUC1-N and MUC1-C) that form a stable heterodimer at the cell surface. MUC1-N is shed to contribute to a protective physical barrier, leaving the oncogenic MUC1-C subunit at the cell surface as a putative receptor for signaling the presence of stress to the interior of the cell. As shown for the VEGF receptor TRAP, aflibercept, a potential approach for blocking MUC1-C function is to generate a soluble decoy receptor by fusing the MUC1-C extracellular domain to an Ig constant (Fc) region. The present studies demonstrate that in vitro treatment of human ZR-75-1 breast carcinoma cells with the MUC1-C soluble decoy receptor is associated with a dose-dependent induction of cell death. Similar findings were obtained with human MCF-7 breast cancer cells. To explore the potential of the MUC1-C soluble decoy receptor as an anti-cancer agent, we evaluated its ability to block the growth of breast cancer cells in subcutaneous tumor xenograft models growing in nude mice. Administration of the MUC1-C soluble decoy receptor to nude mice bearing established ZR-75-1 breast tumor xenografts was associated with a dose-dependent loss of tumorigenicity and prolonged tumor regressions after completing therapy. Taken together, these findings demonstrate that targeting the MUC1-C oncoprotein with a soluble decoy receptor is effective in inducing death of human breast cancer cells in vitro and in tumor models.

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 1819. doi:1538-7445.AM2012-1819
Abstract 1826: Anti-tumorigenic effects by targeted functional disruption of the Sin3 PAH-2 domain
Authors: Ariztia Edgardo V. , Das Tirtha K. , Farias Eduardo F. , Leibovitch Boris , Petrie Kevin , Gil Veronica , Zelent Arthur , Zhou Ming-Ming , Cagan Ross L. , Waxman Samuel
Published: August 2012

The Sin3 A/B adapter proteins function as structural scaffolds for repressor/activator complexes that regulate transcription through the specific association with histone modifying enzymes and a number of transcription factors. Sin3 contains four paired amphipathic α-helices (PAH domains). We have reported earlier that targeted disruption of the PAH2 domain with a SID (Sin3 Interaction Domain) peptide decoy in triple negative (TN) breast cancer cells leads to cytoskeletal reorganization, loss of anchorage independent growth and 3D invasive morphology and decreased cell adhesion and invasion. There is epigenetic reprogramming of silenced genes such as CDH1, ESR1 and RARA which are re-expressed and together contribute to a SID decoy induced switch from basal to a more differentiated luminal phenotype (Farias, et. al., PNAS, 2010, 107:11811-6). Computerized screening coupled with such assays as Duolink, GST pull downs and mammalian two hybrid identified small molecule inhibitors (SMI) that mimic the effects of the SID decoy peptide. SMI inhibit cellular invasion at nanomolar range and in in vivo mouse myc TN breast cancer prolong latency, decrease local invasion and metastasis. Tumors recovered showed evidence of re-expression of E-cadherin and estrogen receptor. Early effects of SID decoy in TN breast cancer cells include inhibition of invasion that is associated with a significant decrease in Src phosphorylation within 2-4hr of treatment. Recovery of phosphorylation after SID decoy washout is coupled with recovered invasion at 24hr. These effects occurred prior to measurable increase in E-cadherin expression, suggesting a non-transcriptional effect. In Drosophila larval breast cancer models with activated Src/Ras, overexpression of SID inhibited (60%) tumor growth in the eye imaginal disc, and was eradicated by the addition of a MEK inhibitor (AZD-6244), indicating a strong synergy between SID and AZD-6244. In the adult fly SID expression greatly inhibited RetMEN2B induced eye tumors (90%). These data demonstrate that SID decoys have a potential to be effective agents in the treatment of TN breast cancer by promoting basal phenotype reversal, inhibiting invasion and metastasis, and could be synergistic with specific inhibitors of signal transduction targets. Moreover, SID decoys can overcome profound oncogenic stimulus such as Ras, Src and Ret suggesting that they have a potential greater role than just in the treatment of TN breast 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 1826. doi:1538-7445.AM2012-1826
Abstract 1835: Phosphodiesterase 4D (PDE4D) selective inhibitors as candidate drugs for prostate cancer
Authors: Marker Paul C. , Hammer Kimberly D.P.
Published: August 2012

Our laboratory used an insertional somatic mutagenesis screen in mice to identify novel genes that may drive prostate cancer initiation and progression. Using this screen, we have identified candidate prostate cancer genes including the candidate oncogene phosphodiesterase 4D (PDE4D). Investigation of PDE4D showed that it was over-expressed in human prostate cancer cell lines and in human prostate cancers. Stable knockdown of PDE4D by shRNA reduced the growth and migration of prostate cancer cells in vitro and in vivo. Several small molecule PDE4D-selective inhibitors have been developed, including cilomilast and NVP-ABE171, and we have used them as potential anti-prostate cancer drugs in vitro and in vivo. The inhibitors were able to reduce the growth of prostate cancer cells in the context of epithelial mono-cultures or co-cultures that modeled stromal-epithelial interactions. Daily oral administration of PDE4D inhibitors for 6 weeks also reduced the growth of several prostate cancer xenograft lines in vivo through a dramatic induction of apoptosis. Interestingly, NVP-ABE171 and cilomilast also reduced the size of the prostates of treated mice without impacting overall animal health or the sizes of other organs. Under in vitro conditions in which prostate cancer cell growth was inhibited by either NVP-ABE171 or cilomilast, we also observed changes in the activation of potential downstream molecular targets of PDE4D inhibition including the sonic hedgehog and mitogen-activated protein kinase pathways. We are continuing studies with these inhibitors to further support the use of NVP-ABE171 and cilomilast as anti-prostate cancer drugs and to understand their mechanism(s) of action in the prostate.

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 1835. doi:1538-7445.AM2012-1835
Abstract 1836: p38α MAPK interacts with and inhibits RARα: Suppression of the kinase enhances the therapeutic activity of retinoids in acute myeloid leukemia cells
Authors: Garattini Enrico , Gianni’ Maurizio , Terao Mineko , Kurosaki Mami , Paroni Gabriela , Loparco Maria Immacolata , Peviani Marco
Published: August 2012

All-trans retinoic acid (ATRA) is the only clinically useful differentiating agent, being employed in the treatment of acute promyelocytic leukemia (APL). The use of ATRA in other types of acute myelogenous leukemia (AML) calls for the identification of novel strategies aimed at increasing its therapeutic activity. One possible strategy to improve the efficacy of retinoids is to identify non-retinoid compounds that enhance the activity of ATRA, focusing on the mechanisms controlling the stability/activation of the nuclear retinoid receptors expressed in the AML blast. An important mechanism modulating the activity of the RAR-containing transcriptional complexes is phosphorylation of RARs and accessory proteins, such as co-repressors and co-activators. The mitogen activated kinase p38alpha, cyclin-dependent kinase 7 (CDK7) and mitogen-and stress-activated kinase (MSK1) stand out as critical determinants in the process. p38alpha is often increased and/or activated in AML blasts and it represents an important pharmacological target as well as a potential determinant of ATRA sensitivity in these cells. Here, we provide evidence that pharmacological inhibition of the mitogen-activated- protein-kinase, p38alpha, or silencing of the corresponding gene sensitizes APL and AML cell lines, as well as primary cultures of AML blasts to the anti-proliferative and cyto-differentiating activity of ATRA and synthetic retinoids. P38alpha inhibits ligand-dependent transactivation of the nuclear retinoic acid receptor, RARalpha, and the derived chimeric protein expressed in the majority of APL cases, PML-RARalpha. Inhibition is the consequence of ligand-independent binding of p38alpha which results in stabilization of RARalpha and PML-RARalpha via blockade of their constitutive degradation by the proteasome. Our data indicate that p38alpha inhibition causes a preferential increase in the relative amounts of RARalpha over those of PML-RARalpha. The inhibitory effect requires a catalytically active p38alpha and direct physical interaction with RARalpha and PML-RARalpha. Ser-369 in the E-region of RARalpha is essential for the binding of p38alpha and the ensuing functional effects on the activity of the receptor. In conclusion, our results add a further layer of complexity to the mechanisms controlling retinoid receptors’ activity and provide the rationale for the use of novel strategies in the treatment of AML patients with a cyto-differentiating approach.

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 1836. doi:1538-7445.AM2012-1836
Abstract 1844: CD43 normally expressed on the surface of leukocytes is expressed in the cytoplasm and nucleus of breast cancer and is a novel therapeutic target
Authors: Shelley Carl S. , Fu Qiangwei , Cash Steven E. , Andersen Jeremiah J. , Kennedy Colin R. , Dietrich Leah L. , Agger William A.
Published: August 2012

One in eight of the female population of the United States will be diagnosed with breast cancer in their lifetime. This statistic defines breast cancer as the most common cancer affecting American women. Advances in breast cancer treatment will be facilitated by the identification and targeting of the causative molecular defects. We have found that breast cancer is characterized by expression of CD43. This sialoglycoprotein is normally only produced by leukocytes. Strikingly, an N-terminal domain of CD43 that is extracellular in leukocytes is expressed predominantly in the cytoplasm of breast cancers. The C-terminal domain that is expressed in the nucleus of leukocytes only upon activation exhibits constitutive nuclear localization in breast cancer. Segregation of the N and C terminal domains of CD43 between different subcelluar compartments suggests that in breast cancer it is subjected to specific proteolytic cleavage events. The normal function of CD43 is to regulate leukocyte adhesion, apoptosis and migration. We reasoned that if these normal functions are extrapolated to breast cancer, then CD43 could contribute to disease progression and, therefore, represent a novel therapeutic target. We tested this hypothesis by using small-interfering RNA to target CD43 expressed by the breast cancer cell line MCF7. This targeting resulted in cancer cells exhibiting increased susceptibility to apoptosis and increased vulnerability to lysis by natural killer cells. In addition, targeting demonstrated that CD43 likely facilitates metastasis by inhibiting homotypic adhesion and driving transendothelial migration. Using an othrotopic mouse model, we demonstrate that CD43-targeting reduces the size of primary tumors by 76%. Taken together, our results indicate that expression of CD43 is a robust breast cancer biomarker and its targeting has the potential to be developed into a new breast cancer therapy.

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 1844. doi:1538-7445.AM2012-1844
Abstract 185: Alteration of microRNA expression profiles in HPV-associated squamous cell carcinoma of the head and neck (SCCHN)
Authors: Oh Ji-Eun , Kim Jeong-Oh , Shin Jung-Young , Zhang Xiang-Hua , Chun Sang-Hoon , Won Hye-Sung , Jung Chan-Kwon , Hong Sook-Hee , Lee Myoung-Ah , Kang Jin-Hyoung
Published: August 2012

Background High-risk type of human papillomavirus (HPV) has recently been found to be etiologically associated with 20 to 25% of SCCHN, particularly common in or pharyngeal tumors. We investigated the protein expression of PTEN/PI3K/AKT/mTOR signal pathway on HPV 16 +/− tonsillar squamous cell carcinomas. And, we analyzed microRNA expression profile in tongue cancer cell line transfected with HPV 16 E6/E7 oncogene. Method Tonsil cancer patients who had been treated at Seoul St. Mary's Hospital between 2000 and 2009 were reviewed. Tissue microarrays were prepared from formalin-fixed, paraffin-embedded tumor tissues of 65 surgical specimens, and stained with antibodies against PTEN, PIK3CA, phosphorylated AktSer473, and phosphorylated mTORSer2448. High-risk HPV infection status was determined by in situ hybridization. The protein expression of EGFR, PIK3CA, pAkt, mTOR, and PTEN was assessed by immunohistochemistry. MicroRNA expression was studied using microarrays (PANArray™ miRNA expression profiling kit) in two tongue cancer cell lines (YD8 and YD10B) transfected with HPV 16 E6/E7 oncogene. Results Of the 65 pts, 26 (40%) pts were HPV positive. Overall survival and relapse-free survival were significantly different between two groups (P = 0.05 and P = 0.036, respectively). PTEN expression was significantly higher in HPV-positive- than in HPV-negative patients (P = 0.02). PIK3CA, phosphorylated AktSer473, and phosphorylated mTORSer2448 expression was negatively correlated with HPV status, yet not significantly. HPV status (P = 0.03) and nodal stage (P = 0.05) were found to significantly affect overall survival, as determined by multivariate analysis. The expression profile of miRNAs was different in HPV 16 E6/E7 transformed cells compared with vector alone cells. In the final round, 8 of 158 miRNAs were selected to be most differently expressed miRNAs; let-7b, miR-1, miR-107, miR-122, miR-127-5p, miR-95, miR-23b and miR-370 (>1.2-fold). Conclusion We observed the higher expression of PTEN in HPV 16 positive tonsil tumor than HPV 16 negative tumor. Our data suggest that some microRNAs induced by E6/E7 oncogene might directly affect PTEN expression level independent of p53. We are underway on the experiments confirming that PTEN is regulated by which among these miRNAs.

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 185. doi:1538-7445.AM2012-185
Abstract 1854: Lysophosphatidic Acid Acyltransferase-Beta contributes to proliferation and anchorage-independent growth in pancreatic adenocarcinoma
Authors: Blaskovich Michelle , Gevariya Harsukh , Lawrence Nicholas J. , Sebti Saïd M. , Springett Gregory
Published: August 2012

Abstract: Lysophosphatidic acid acyltransferase-beta (LPAAT-α) catalyzes the production of phosphatidic acid (PA) from lysophosphatidic acid (LPA). PA is a lipid cofactor that contributes to the activation of c-Raf, BRAF, mTOR and PKC-α. LPAAT-α expression is a prognostic factor in gynecologic malignancies and is being investigated as a therapeutic target in a variety of tumor types. We previously reported that LPAAT-α is expressed in pancreatic cancer cell lines and in human pancreatic adenocarcinoma tissues. We employed siRNA knockdown of LPAAT-α expression in pancreatic cancer cells in vitro. We find that reduction in the expression of LPAAT-α protein is associated with decreased proliferation and impairment in anchorage dependent growth of pancreatic cancer cells. Methods: MiaPaCa and Panc-1 cells were transfected with two different siRNAs targeted to LPAAT-α at 10 nM and 25 nM for 48 hrs and 72 hrs. A non-targeting siRNA was used as a control. The cells were then plated on tissue culture dishes or in soft agar and allowed to proliferate. Proliferation on plastic dishes was measured using Alamar Blue. Colony formation in soft agar was determined by directly counting macroscopic colonies. Results: Transfection of MiaPaCa and Panc-1 cells with siRNA at 25 nM for 72 hours achieved almost 100% inhibition of LPAAT-α protein expression by Western blotting. Under these conditions there was a 50% reduction in proliferation and colony formation. Studies to determine the effects of depleting LPAAT-α on the levels of p-PKC-α, p-MEK, p-4E-BP1 and p-S6Kinase are ongoing and will be presented. Conclusions: Suppression of expression of LPAAT-α protein in pancreatic cancer cell lines reduces proliferation and anchorage independent growth. This contributes to the validation of LPAAT-α as a therapeutic target in 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 1854. doi:1538-7445.AM2012-1854
Abstract 1861: EPHB4 as a potential therapeutic target for esophageal cancer
Authors: Hasina Rifat , Mutreja Karun , Kawada Ichiro , Kanteti Rajani , Arif Qudsia , Liu Ren , Li Xiuqing , Zhou Yue , Hyjek Elizabeth , Lingen Mark W. , Mueller Jeffery , Waxman Irving , Villaflor Victoria , Ferguson Mark , Vokes Everett E. , Gill Parkash , Salgia Ravi
Published: August 2012

Despite substantial improvements in screening, diagnosis, and treatment of esophageal cancer, the prognosis of this disease remains bleak. Survival at 5 years for all esophageal cancer patients taken together, with amenable treatments and with or without surgery ranges from 5-20% (Cancer Facts and Figures. American Cancer Society 2011). Although a multidisciplinary approach to include surgery, radiation, and chemotherapy, alone or in combination, attempts to improve the survival of this aggressive disease, these statistics underscore the continued need for attention to this disease and for identification of new targets in its treatment. We have been studying the role of receptor tyrosine kinases (RTKs) in cancer, particularly the EphB4 receptor, which has become increasingly associated with the pathobiology of adult cancers over the past several years. It has been shown to be aberrantly expressed and/or to play an oncogenic role in cancers of the breast, bladder, ovary, uterus, colon, head and neck, and prostate through its effects on cellular motility, growth, and migration, as well as on tumors’ ability to induce neoangiogenesis. To date, its role and potential as a target for therapy in different cancers have not been thoroughly investigated and remain poorly understood. Targeted inactivation of EphB4 and its ligand Ephrin-B2 have demonstrated that both are essential for angiogenic remodeling and embryonic survival (Adams and Klein 2000; Kim, Hu et al. 2008). In this report, we determine that EphB4 is overexpressed, has increased gene copy number and is involved in enhanced motility and migration in esophageal cancer. Archival patient samples consisting of 93 squamous cell carcinoma, 100 adenocarcinoma and 25 adjacent normal control samples as well as four adenocarcinoma and nine squamous cell carcinoma cell lines were used for the studies. Extensive mouse modeling of esophageal cancer was also used. We have reported that there is consistently higher expression of EphB4 in both squamous and adenocarcinoma compared to adjacent normal tissue with a statistically significant correlation between EphB4 expression and higher grades of squamous cell carcinoma. In a chemically induced esophageal squamous cell carcinoma model in mice, EphB4 was found overexpressed compared to normal controls. This study identifies EphB4 to be an important pathway in esophageal neoplastic lesions. It would now be useful to bring this to clinical fruition.

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 1861. doi:1538-7445.AM2012-1861
Abstract 1866: Genome-wide association study for irinotecan-related severe toxicities in patients with advanced non-small cell lung cancer
Authors: Han Ji-Youn , Shin Eun Soon , Ghang Ho Young , Lee Yeon-Su , Lee Jin Soo
Published: August 2012

Purpose: We performed a case-control genome-wide association study (GWAS) to identify single nucleotide polymorphisms (SNPs) associated with severe diarrhea and neutropenia in patients treated with irinotecan for advanced non-small cell lung cancer (NSCLC). Patients and Methods: We performed a case-control GWAS using the Affymetrix 5.0 array set in 103 patients enrolled in two phase II studies of with irinotecan and cisplatin. A subsequent replication study was conducted to validate major GWAS findings in an independent series of 146 patients enrolled in another phase II study of irinotecan-based chemotherapy. Cases were defined as patients with grade 3 diarrhea (G3D) or grade 4 neutropenia (G4N) according to the National Cancer institute's Common Terminology Criteria for adverse events v3.0. Results: The GWAS included 11 G3D (control 90) and 24 G4N (control 77). The replication set included 13 G3D (control 133) and 21 G4N (control 125). GWAS identified 49 and 32 SNPs putatively associated with G3D and G4N, respectively. In the replication series, SNPs, rs1517114 (C8orf34), rs1661167 (FLJ41856), and rs2745761 (PLCB1) were confirmed for G3D, and rs11128347 (PDZRN3), rs11979430 and rs7779029 (SEMAC3) were confirmed for G4N. Conclusion: This GWAS screen along with subsequent validation indentified novels SNPs associated with irinotecan-related severe toxicities.

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 1866. doi:1538-7445.AM2012-1866