bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 2351: Evaluation of KRAS and BRAF mutation analysis in primary metastatic colorectal cancers versus matched syn- and metachronous metastases
Authors: Dietmaier Wolfgang , Kiesl Alexander , Lang-Schwarz Corinna , Ruemmele Petra , Groeschl Benedikt , Hofstaedter Ferdinand
Published: February 2011

Background: The KRAS mutation status was shown in recent studies to be a predictive biomarker for anti-EGFR monoclonal antibody (mAB) therapy in metastatic colorectal cancer (mCRC). Patients without KRAS mutations (wild type KRAS) did benefit from anti-EGFR-mAB therapy whereas patients with tumors bearing a KRAS mutation did not benefit from this targeted therapy. KRAS mutation analysis is thus required before anti-EGFR-mAB treatment in all mCRCs. As published in the clinical studies, primary tumors are commonly used as the standard tissue. However, KRAS mutation analysis is often complicated because primary tumors are being discarded by many institutes of pathology years after diagnosis. Instead recent metastases are available and are used for KRAS mutation analysis. However the question is raised if primary tumors and metastases are equally informative regarding the KRAS and BRAF mutation status especially when considering the multiple steps during tumor cell dissemination and metastatic processes. So far only little and heterogeneous data are available about this issue. Patients and methods: To address this question we performed a KRAS mutation analysis (codons 12, 13, 61) in 111 colorectal cancers and 171 matched metastases in lymph nodes, liver, lung, ovary, peritoneum, brain, urinary bladder and bone. Additionally, BRAF mutation analysis was done in all KRAS wild type tumors. In addition, multiple (>=2) matched synchronous or metachronous metastases and corresponding primary tumors were analysed in 44 cases. KRAS and BRAF mutation analysis was done using pyrosequencing technology. Tumor cells were gained either by microscopically controlled manual microdissection or by laser assisted microdissection. Results: Primary tumors and matched metastases with initially discrepantly appearing KRAS mutation status were re-analysed using laser-microdissection. By means of laser microdissection we finally did not find any discrepancies in the KRAS and BRAF mutation status in primary tumors versus matched syn- or metachronous metastases. Conclusion: KRAS and BRAF mutation analysis in metastases appears to be as valid as in primary tumors and should serve as reliable specimens in cases where primary tumors are not available to predict response to therapies with anti-EGFR targeted monoclonal antibodies in metastatic colorectal cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2351.
Abstract 2366: Reduced ecto-5′-nucleotidase CD73 expression and altered purine nucleotide metabolism in colorectal cancer cells robustly causing liver metastases
Authors: Matsuyama Masahiro , Wakui Masatoshi , Monnai Makoto , Mizushima Tomoko , NIshime Chiyoko , Kawai Kenji , Suemizu Hiroshi , Hishiki Takako , Suematsu Makoto , Murata Mitsuru , Chijiwa Tusyoshi , Furukawa Daisuke , Ogoshi Kyoji , Makuuchi HIroyasu , Nakamura Masato
Published: February 2011

Liver metastases are frequently inoperative and severely impact the prognoses of patients with cancers. Colorectal cancers as well as pancreatic cancers most commonly metastasize to the liver, although there are some patients with colorectal cancers presenting liver metastases operative contrary to the cases of pancreatic cancers. Through liver metastasis models using NOD/SCID/IL-2Rγcnull (NOG) mice, we have previously established and examined a highly liver-metastatic human pancreatic cancer cell subline, which was derived from the poorly liver-metastatic parental line, identifying a key molecular regulator of liver metastasis. In the present study, we established a highly liver-metastatic human colorectal cancer cell subline SW48LM2 through the serial intrasplenic transfer of cells derived from poor but visible hepatic tumor foci formed by parental SW48 cells transferred to NOG mice. The growth both under monolayer-culture conditions and during formation of the subcutaneous tumors was similar between the two cell lines, although there were morphological differences in the in vitro spheroid formation. Of 41 molecules reportedly associated positively or negatively with tumor progression, four were overexpressed and four were underexpressed in SW48LM2 cells. Most strikingly, this liver-metastatic cell subline exhibited strongly reduced expression of the ecto-5′ -nucleotidase CD73 as well as altered metabolism of purine nucleotides. Contrary to previous studies showing a positive correlation between CD73 expression and metastatic cancer phenotypes, reduced CD73 expression on tumor cells may contribute to the potential of liver metastases. The present study highlights the need for interpretative caution when investigating metastasis-associated molecules for the diagnostic and therapeutic applications, providing insights into the mechanisms of liver metastases.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2366.
Abstract 2367: RSK2 promotes head and neck cancer cell invasion through direct phosphorylation of Hsp27 to regulate actin filaments
Authors: Elf Shannon , Lythgoe Katherine , Hitosugi Taro , Taunton Jack , Zhou Wei , Xiong Li , Wang Dongsheng , Muller Susan , Fan Songqing , Sun Shi-Yong , Chen Zhuo (Georgia) , Khuri Fadlo R. , Chen Jing , Shin Dong M. , Kang Sumin
Published: February 2011

Head and neck squamous cell carcinoma (HNSCC) is one of the most common types of human cancers and frequently metastasizes to lymph nodes. We found that the protein expression pattern of p90 ribosomal S6 kinase 2 (RSK2) correlates with the invasive ability of diverse HNSCC cell lines, and with human head and neck cancer progression. Continued RSK2 expression is vital for maintenance of the invasive and metastatic potential of HNSCC cells in vitro and in vivo, respectively. In a phospho-antibody microarray-based study, we identified pro-metastatic protein factors that are phosphorylated and activated by RSK2, including the previously identified CREB and a newly identified RSK2 substrate Hsp27, which are important for the RSK2-mediated pro-invasive ability of HNSCC cells.

Hsp27 has been found to be overexpressed in many types of cancers, and its overexpression is associated aggressive tumor behavior. Here we found that RSK2 promotes stabilization of actin filaments in HNSCC cells through phosphorylation and activation of Hsp27 RNAi-mediated knockdown of Hsp27 significantly attenuated HNSCC Tu212 cell invasion conferred by exogenous expression of RSK2. In an in vitro kinase assay using purified recombinant Hsp27 WT and individual S15A, S78A or S82A mutant proteins incubated with active recombinant RSK2, we found that RSK2 directly phosphorylates Hsp27 at S78 and S82, but not S15. Moreover, stable expression of phospho-mimetic Hsp27 S78D/S82D double mutant led to further significantly enhanced cell invasion of poorly invasive HNSCC Tu212 and 686LN cells, compared to exogenous expression of Hsp27 WT. Stable expression of Hsp27 S78D/S82D mutant, but not WT or S78A/S82A mutant, rescued the cell invasion and tumor metastasis attenuated by stable knockdown of RSK2 in highly invasive HNSCC M4e cells in vitro and in vivo using xenograft mice, respectively.

Hsp27 regulates actin dynamics and apoptosis. Actin immunofluorescent staining showed that RNAi-mediated stable knockdown of RSK2 resulted in disruption of actin filaments in 212LN and M4e cells. However, stable expression of the Hsp27 phospho-mimetic mutant S78D/S82D, but not WT or the phospho-deficient S78A/S82A mutant, rescued the formation of actin filaments.

Our findings demonstrate that RSK2 signals through Hsp27 to regulate actin filaments and cell invasion via direct phosphorylation of Hsp27 at Ser78 and Ser82. This may represent a transcription-independent mechanism underlying RSK2-mediated pro-metastatic signaling in HNSCC cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2367.
Abstract 2368: Autotaxin/Enpp2 controls of bone metastasis formation through osteoclast function
Authors: David Marion , Wannecq Estelle , Jansen Sylvia , Deux Blandine , Ribeiro Johnny , Serre Claire-Marie , Grès Sandra , Bendriss-Vermare Nathalie , Bollen Mathieu , Saulnier-Blache Jean-Sébastien , Clézardin Philippe , Peyruchaud Olivier
Published: February 2011

Autotaxin (ATX, NPP-2) is a secreted protein with both an oncogenic action on mouse breast tissue and metastatic properties on breast cancer cells. Due to its lysophospholipase D activity, ATX generates lysophosphatidic acid (LPA) from lysophosphatidylcholine and controls LPA levels in the blood. We have recently showed that platelet-derived LPA promotes the progression of osteolytic bone metastases of breast cancer cells. However, how LPA is produced at the metastatic site and the role of ATX by cancer cells in this metastasis process are still unknown. Here, we found that in vitro, forced expression of ATX in human breast cancer MDA-B02 cells (MDA-B02/ATX) increased invasiness, proliferation and enhanced their pro-osteoclastic function. In vivo, intravenous injection of MDA-B02/ATX cells to inmmunodeficiency BALB/C nude mice enhanced osteolytic bone metastasis formation, as judged by increased bone loss and tumor burden, and higher active osteoclast number at the bone metastatic site. Mouse 4T1 breast cancer cells induced the formation of osteolytic bone metastases after intracardiac injection in immunocompetent BALB/C mice. We found that 4T1 cells expressed active ATX. In vitro, silencing ATX[O1] expression inhibited invasion but not proliferation of 4T1-siATX cells. In vivo, silencing ATX expression inhibited the extent of osteolytic bone lesions and decreased the number of active osteoclasts at bone the metastatic site. Altogether, these results demonstrated that expression of ATX by cancer cells controls bone metastasis formation and that targeting ATX in patients might contribute to the development of additional therapies against bone metastases.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2368.
Abstract 2371: Arid4b is a potential breast cancer progression modifier gene
Authors: Winter Scott F. , Lukes Luanne , Hunter Kent W.
Published: February 2011

Our laboratory's research focuses on the role of host genetics in breast cancer metastasis. The MMTV-PyMT mouse model exhibits varying metastatic efficiency to the lungs when transgenic mice in an FVB background are bred to other strains such as DBA and AKR. Combining quantitative measurement of metastasis with genetic mapping studies of the AKXD recombinant inbred panel of mice has allowed us to determine quantitative trait loci (QTLs) that affect metastatic efficiency. My work has focused on the potential role of Arid4b in breast cancer tumorigenesis and metastasis. Arid4b is a component of the mSin3a histone deacetylase complex that has a known role in breast cancer progression and is a candidate gene underlying a metastasis QTL peak we have identified on mouse chromosome 13. In two independent mouse breast cancer cell lines, Met-1 and PyMT-luc, stable expression of the AKR (high metastatic strain) allele caused significantly larger primary tumor growth than the DBA (low metastatic strain) allele following orthotopic implantation into the mammary fat pads of syngeneic hosts. In Met-1 cells we detected lung surface metastases in the AKR cohort but not in the DBA cohort. We are in the process of performing functional analyses to determine a mechanism of action whereby Arid4b polymorphisms influence tumorigenesis and metastasis. Sequencing has revealed a high density of non-synonymous SNPs between the AKR and DBA alleles in exon 22, which encodes a C-terminal region of the Arid4b protein that is known to mediate interaction with the mSin3a HDAC complex. We are currently using co-IPs and proteomics strategies, such as tandem affinity purification, to identify proteins that bind differentially to the AKR or DBA Arid4b proteins. Arid4b is also alternately spliced and cells ectopically expressing the shorter isoform 2 formed significantly larger tumors in our orthotopic model compared to cells expressing the full-length isoform 1. Interestingly, the alternately spliced exon encodes part of a conserved Chromodomain, which is known to mediate binding of other Chromodomain containing proteins such as HP1 to modified histone tails. Western blots using an Ab specific for dimethylated histone H3 lysine 27 suggest a potential role of Arid4b in modifying chromatin structure. It is likely that both the alternate splicing of the Chromo domain and the allelic variation in the C-terminal domain modulate the epigenetic influence of Arid4b on tumorigenesis and metastasis.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2371.
Abstract 2375: Nodal regulates the angiogenic switch in breast cancer
Authors: Quail Daniela , Zhang Guihua , Postovit Lynne-Marie
Published: February 2011

Highly aggressive breast tumours undergo dedifferentiation, by displaying tissue-nonspecific gene expression patterns and stem cell-like phenotypes. Nodal is an embryonic morphogen responsible for maintaining plasticity in embryonic stem cells, and is aberrantly expressed in aggressive cancers. The current study reveals a positive correlation between Nodal and aggressive breast cancer phenotypes. Specifically, Nodal promotes self-renewal through single-cell non-adherent spheroid formation, anchorage-independent growth on soft agar, and tube formation by endothelial cells in vitro. Additionally, Nodal promotes angiogenesis in vivo. Similar to its role in embryonic morphogenesis, Nodal may be responsible for promoting the dedifferentiated phenotype of breast cancer, and subsequent angiogenic switch. Since the angiogenic switch is a precursor to metastasis, Nodal may be useful as a prognostic marker or therapeutic target for metastatic disease.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2375.
Abstract 2380: Carcinoembryonic antigen (CEA) directly activates endothelial cells, thereby inducing (tumor)-angiogenesis
Authors: Bramswig Kira H. , Poettler Marina , Kalinowska Waclawa , Binder Bernd R. , Zielinski Christoph C. , Prager Gerald W.
Published: February 2011

Angiogenesis has become a major target in treatment of a varietly of cancers, whereby the major angiogenic growth factor VEGF is currently in focus for therapeutic interventions. Nevertheless, the use of VEGF-targeting drugs has been shown to be of limited efficacy, which might lie in the fact that tumor angiogenesis is not only induced by VEGF, but also by a variety of other factors.

In this study, we report that the human carcinoembryonic antigen (CEA), a GPI-anchored cell surface adhesion molecule, which is shedded by 70% of human cancers, directly binds to endothelial cells, thereby inducing angiogenic endothelial cell behavior in vitro and in vivo:

Overexpressing CEA in endogenous negative renal cell cancer (RCC) cell line or in the sarcoma cell line MethA led to an enhanced tumor angiogenesis and an increase in tumor growth in vivo, effects which were reverted by downregulation of the CEA receptor in endothelial cells via a lentiviral shRNA construct. Furthermore, targeting CEA by CEA mimotope immunized BALB/c mice, led to a breakdown In tumor vascularization, which was reflected by retarded tumor growth. We found that CEA, by binding to its receptor, led to an increase in integrin activation state, leading to enhanced endothelial cell adhesion, followed by amplified adhesion-induced signal transduction, which involved c-src-activation, focal adhesion kinase (FAK) and ERK phosphorylation, as well as PI3kinase/Akt activation. As a consequence, pro-angiogenic endothelial cell behavior, such as migration and invasion or proliferation were induced. Whenever integrin beta-3 were blocked, CEA was effect less in endothelial cells.

These results show that the tumor marker CEA might bear hitherto undescribed biological significance in promoting tumor-angiogenesis. Thus, CEA-mediated signaling may offer a potential novel therapeutic target for the treatment of cancer.

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

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2380.
Abstract 2381: Neoangiogenesis correlates with increased breast density, calcitonin gene related peptide positivity and cell proliferation seeking radiotracer uptake in mixed invasive ductal associated with in situ, but not in pure invasive breast carcinoma
Authors: Papantoniou Vassilios , Tsaroucha Angeliki , Dimitrakakis Constantine , Marinopoulos Spyridon , Sotiropoulou Evangelia , Valsamaki Pipitsa , Fothiadaki Athina , Karianos Theodore , Archontaki Aikaterini , Sotiropoulou Maria , Syrgiannis Konstantinos , Antsaklis Aris
Published: February 2011

Aim: To assess neoangiogenesis in relation to breast density (BD), calcitonin gene related peptide (CGRP), cell proliferation seeking radiotracer 99mTc-(V)DMSA uptake (SMM) in invasive ductal associated with extensive in situ carcinoma (DCIS + IDC) and in pure invasive breast carcinoma (IDC).

Methods: 20 patients with histologically confirmed mixed DCIS + IDC (n=10) and pure IDC (n=10) were submitted preoperatively to mammography and scintimammography. The percentage of breast density (BD) and the percentage of tracer uptake (SMM) were calculated with computer assisted methods. CGRP and the number of newly formed blood vessels (NBV) were immunohistochemicaly assessed. NBV, BD, CGRP, and SMM were compared (t-test) between the two groups. Linear regression analysis was performed between NBV, BD, CGRP and SMM in both groups.

Results: NBV, BD, CGRP and SMM were significantly higher in mixed DCIS + IDC as compared to pure IDC (32.1±10.4 vs 24.3±5 p=0.048, 35.2 ± 6.9 vs 25.6±10.7 p=0.028, 25.5±7.6 vs 17±7.8 p=0.024, 26.75±4.09 vs 11.34±8.5 p=0.0009). NBV was strongly correlated with BD and CGRP in the DCIS component of the mixed group (r=0.933 p<0.001, r=0.793 p<0.01 respectively). BD was also significantly correlated with CGRP and SMM in the DCIS component of the same group (r=0.974 p<0.001, r=0.728 p<0.05 respectively). In contrast, no significant correlation(NS) was found between NBV and BD, CGRP or between BD and CGRP, SMM in both the IDC component of mixed group and pure IDC group (r=0.388 NS, r=0.391 NS, r= − 0.597 NS, r= − 0.352 NS in the IDC component of mixed group; r=0.584 NS, r= 0.297 NS, r= − 0.574 NS, r= −0.294 NS in pure IDC respectively).

Conclusion: Mixed DCIS + IDC lesions exhibit significantly increased NBV, BD, CGRP and SMM values as compared to those of IDC lesions. The strong correlation between neoangiogenesis and the other parameters in the mixed group indicates that the mixed DCIS + IDC constitutes a strictly different entity from pure IDC, more aggressive and probably originates from the stroma through the CGRP pathway.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2381.
Abstract 2389: uPA and uPAR siRNA inhibits angiogenesis by blocking nuclear localization of angiogenin and angiopoietin1 signaling in glioblastoma cell lines
Authors: Raghu Hari , Song Ju Han , Fassett Daniel , Klopfenstein Jeffrey D. , Dinh Dzung H. , Gujrati Meena , Rao Jasti S.
Published: February 2011

Transcriptional inactivation of uPA and uPAR system in the glioblastoma cell line SNB19 inhibited angiogenesis both in vitro and in vivo. To decipher this mechanism and extend our studies to other glioblastoma cell lines, U87MG and U87 SPARC-overexpressing cell lines were subjected to uPA, uPAR and U2 (bicistronic construct against uPA and uPAR) downregulation by siRNA. In the present study, the bicistronic construct against uPA and uPAR caused significant inhibition of angiogenesis by in vitro angiogenesis assay and in vivo dorsal skin fold chamber models in both cell lines. Increased apoptosis was seen in siRNA downregulated gliomablastoma cells when compared with control cells by FACS analysis. MTT assay revealed significant inhibition of proliferation by U2 siRNA treatment in both cell lines. Transfection with siRNA against uPA and uPAR in co-cultures of glioma cells with endothelial cells showed significant inhibition of angiopoeitin1, IL-6, GRO and GM-CSF while SPARC-overexpressing U87 cells had decreased secretion of angiogenin, GRO, MCP-1, PDGFBB, VEGF and angiopoietin1 by protein array analysis. Bicistronic construct showed decreased levels of angiogenin by ELISA and Western blot in endothelial cells and in cocultures with cancer cells. Transcriptional inactivation of uPA and uPAR showed significant downregulation of angiogenin-induced phosphorylation of ERK, JNK and Akt signaling in endothelial cells. Nuclear translocation of angiogenin in semi-confluent human umbilical vein endothelial cells treated with conditioned medium from siRNA-transfected U87 SPARC-overexpressing cells was inhibited as shown by Western blot and immunofluorescence analyses. Conditioned medium from U87MG and U87 SPARC-overexpressing cells transfected with uPA, uPAR and U2 siRNA plasmids significantly inhibited the phosphorylation of Tie2 receptor in endothelial cells. uPA and uPAR downregulation significantly downregulated MMP-2 levels by gelatin zymography in co-cultures and in single cultures of cancer cells. Matrix metalloproteinase array analysis showed significant inhibition of MMP-3 in co-cultures of U2-transfected SPARC-overexpressing glioma cells. Overall, our results suggest that the simultaneous downregulation of uPA and uPAR inhibits angiogenesis by inhibition of nuclear localization of angiogenin, angiopoeitin 1 signaling and MMP-2 downregulation in endothelial cells. In summary, these results identify novel mechanisms by which the bicistronic construct against uPA and uPAR inhibits angiogenesis, thereby suggesting the potential use of U2 as an anti-angiogenic agent against glioblastoma.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2389.
Abstract 2413: Preventing the development of breast cancer by immunizing with multi-antigen vaccines targeting breast cancer proteins
Authors: Disis Mary L. , Gad Ekram , Herendeen Dan , Cecil Denise , Park Katie , Lai Vy , Lu Hailing , Lubet Ronald
Published: February 2011

Vaccines have been extremely successful in the prevention of infectious diseases. Although cancer vaccines have long been studied for the treatment of cancer, they have not been exploited as chemoprevention agents except in virally mediated malignancies. Human breast cancer is immunogenic and a variety of proteins involved in the malignant transformation or maintenance of the malignant phenotype have been identified as tumor antigens. Transgenic animal models are uniquely suited for evaluating the potential efficacy of preventative cancer vaccines. TgMMTV-neu mice, for example, develop neu-mediated breast cancer at about 150-200 days of life. Tumors are histologically similar to human breast cancer and have a molecular profile consistent with the luminal subtype. We have developed a multi-antigen vaccines targeting immunogenic proteins associated with oncogenesis and evaluated whether we could prevent the development of breast cancer in TgMMTV-neu mice. The vaccine is composed of 3 different antigens. Class II epitopes derived from antigenic proteins involved in growth factor pathways comprised the vaccine. The ability of active immunization to prevent breast cancer was evaluated in both older (18 week) and younger (5 week) mice. Vaccines were administered intradermally every two weeks for 3 immunizations and then monthly until the development of disease or 1 year had passed. The vaccine prevented breast cancer development in some older animals. 40% of peptide immunized older mice were cancer free at 1 year compared to 5% of controls (p=0.02). Protection from the development of cancer was mediated by T cells as evidenced by adoptive transfer of CD3+ cells purified from vaccinated and protected mice, sham immunized mice, and naïve mice. T cells from protected mice resulted in significant inhibition of tumor growth after a syngeneic tumor challenge (p=0.01 protected vs. sham vaccine). Prevention of breast cancer was more pronounced in the older animals when immunization was combined with oral chemoprevention agents. The cancer protective effect of immunization was more pronounced when vaccines were administered to the younger mice. The Class II epitope vaccine prevented cancer development in 65% of mice as compared to 5% of controls. These data suggest breast cancer vaccines targeting biologically relevant proteins may be an effective approach to the prevention of breast cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2413.
Abstract 242: Analyses of novel genes encoding secreted and transmembrane proteins identified by CAST method: CDON is highly expressed in prostate cancer
Authors: Tetsutaro Hayashi , Oue Naohide , Anami Katsuhiro , Sakamotro Naoya , Sentani Kazuhiro , Ohara Shinya , Teishima Jun , Matsubara Akio , Yasui Wataru
Published: February 2011

Prostate cancer (PCa) is one of the most common human cancers. Identification of novel genes that encode membrane-spanning or secreted proteins expressed specifically in PCa has a great advantage to develop of ideal biomarkers for cancer diagnosis and therapeutics. Escherichia coli Ampicillin Secretion Trap (CAST) is a signal sequence trap method to identify genes encoding cell surface and secreted proteins. In this study, to identify novel diagnostic and therapeutic targets of PCa, CAST method was used. We generated cDNA libraries from normal prostate and two PCa cell lines, LNCaP and DU145. These CAST libraries were ligated into the pCAST which was plasmid with a mutant beta-lactamase lacking the endogenous signal peptide. Survival on ampicillin was observed only when various cDNA fragments encoding a signal sequence were inserted. We sequenced 960 ampicillin-resistant colonies for normal prostate CAST library, 1344 colonies for LNCaP CAST library and 960 colonies for DU145 CAST library. By comparing these sequences to those deposited in the public databases using BLAST (NCBI), 223 genes from normal prostate CAST library, 234 genes from LNCaP and 228 genes from DU145 were identified. To extract highly expressed genes in PCa, the genes expressed in normal prostate were excluded. Quantitative RT-PCR analyses of 64 candidate genes were performed and compared mRNA levels in 9 PCa tissues, 2 normal prostate tissues and 14 kinds of normal tissues. Quantitative RT-PCR analyses revealed that CDON was highly expressed in PCa. Overexpression of CDON (tumor/normal ratio > 2) was observed in 8 (89%) of 9 PCa tissues. CDON is a cell surface receptor of the immunoglobulin /fibronectin type III repeat family. By western blot analysis, low to moderate CDON expression was noted in LNCaP cell extracts and moderate to high CDON expression was noted in DU145 cell extracts. The expression of CDON in LNCaP and DU145 was suppressed by treatment with CDON specific siRNA. Cell invasion assay and MTT assay revealed that knockdown of CDON in LNCaP cells did not inhibit both cell growth and invasion ability, but knockdown of CDON in DU145 cells inhibited both cell growth and invasion ability.

In conculusion, CAST is a robust and rapid method to identify cell surface and secreted proteins. CDON was up-regulated in PCa and participated in cell growth and invasion. These finding suggest that CDON may be a good therapeutic target.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 242.
Abstract 2427: Overexpression of insulin/IGF hybrid receptor as predictive biomarker of response to a humanized anti-insulin like growth factor-I receptor monoclonal antibody (CP751,871) in gastric and hepatocellular carcinoma cells
Authors: Kim Jun-Gyu , Kim Hwang Phill , Yoon Young Kwang , Han Sae Won , Im Seock-Ah , Oh Do-Youn , Bang Yung-Jue , Kim Tae You
Published: February 2011

Insulin-like Growth factor I receptor (IGF-IR) is highly expressed in many human cancers and plays a major role in proliferation, survival, and metastasis. Accordingly, abundant IGF-1R targeting drugs, especially monoclonal antibody drugs, have been focused and developed due to their safety and efficacy. In order to define biomarkers correlating with the drug sensitivity, we screened 10 gastric and 10 hepatocellular cancer cell lines, for in vitro response to CP-751,871, anti-insulin like growth factor type 1 receptor antibody. Our results show that CP-751,871 inhibits IGF-1 ligand-dependent IGF-1R phosphorylation and downstream signaling of the two major IGF-1R pathways, mitogen-activated protein kinase and phosphatidylinositol 3′-kinase/AKt. Moreover, long-term exposure to CP-751,871 also caused to decrease phospho-stat 3 as well as phospho-Akt level and induced G1 phase cell cycle arrest in dose-dependent manner preferentially in the sensitive cells. Surprisingly, among these 20 cell lines, cells with IGF-IR and insulin receptor (IR) were significantly inhibited by CP-751,871 compared to cells with IGF-IR or IR overexpression only. Considering their highly homologous structure, we thereby determined if the effect of CP-751,871 had relevance to the level of IR/IGF1R hybrid receptors through co-immunoprecipitation with either CP-751,871 or IGF1R antibody. Its immunoblot analysis revealed that not only did sensitive cell lines, such as SNU719, SNU368, and HepG2, show relatively higher levels of IR/IGF1R hybrid, but also superior ability of CP-751,871 to recognize their IR/IGF1R heterodimer complexes. Furthermore, we could observe that the hybrid forms were recruited by IGF1 ligands but this IGF-I ligand dependent formation was blockaded by CP-751,871. Lastly, the treatment of these sensitive cell lines with CP-751,871 caused dimer dissociation. Therefore, our data suggest that the antiproliferative effect by CP-751,871 requires the co-expression of IGF-1R and IR and may be related with the expression level of hybrid Insulin/IGF-1 receptors in gastric and hepatocellular carcinoma cell lines.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2427.
Abstract 2451: A novel humanized anti-CD40 RabMAb exhibits potent efficacy in preclinical models
Authors: Zhang Yongke , Dai Jihong , Ke Yaohuang , Li Wenjun , Yu Qiu , Li Mingzhen , Feng Lifeng , An Zhiqiang , Yu Guo-Liang , Zhu Weimin
Published: February 2011

Monoclonal antibodies directed against B cell antigens have shown clinical benefits to hematologic malignancies. CD40 is a member of the TNFR superfamily and is a target for potential treatment of B cell lineage hematological malignancies as well as certain carcinomas. To date, majority of the therapeutic monoclonal antibodies are of murine origin. To evaluate the therapeutic potential of rabbit monoclonal antibodies (RabMAb®), we generated functional RabMAbs against CD40 using Epitomics' RabMAb® platform. Here we report the characterization of EPI0050, a novel humanized anti-CD40 rabbit monoclonal antibody. EPI0050 specifically recognizes the CD40 ligand binding domain and selectively blocks the ligand binding to CD40. EPI0050 itself exhibits modest agonist effects as shown in the up-regulation of CD80, CD83 and CD86 in differentiated dendritic cells and direct inhibition of CD40 positive malignant B cells. EPI0050 bound CD40 strongly without much internalization, which conferred to a potent ADCC effect in vitro. In an established preclinical Ramos lymphoma model, EPI0050 significantly inhibited tumor growth with a long-term stabilization of the tumor post dosing as compared with Rituximab and another anti-CD40 antibody. EPI0050 was also able to regress established rebound tumors post Rituximab treatment. More animal models and MOA are being explored for EPI0050. Both in vitro and in vivo results support the preclinical and clinical development of EPI0050 as a bio-better tumor therapy.

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

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2451.
Abstract 2452: Efficacy and toxicity of an anti-CD19 antibody drug conjugate
Authors: Rao Chetana , Pan Chin , Vangipuram Rangan , Huber Mary , Vemuri Kavitha , Stevens Alice , Chong Colin , Cortez Orville , Sung Janette , Derwin Dan , Passmore David , Zhang Qian , Gangwar Sanjeev , Cardarelli Pina , Deshpande Shrikant
Published: February 2011

CD19 is an attractive target for immunotherapy. The expression of CD19 is restricted to B cells and follicular dendritic cells. In B cells, expression is initiated at the point of B lineage commitment and continues through the pre B and mature B cell differentiation. Expression is lost during the terminal differentiation of B cells to plasma cells. CD19 expression continues in B-lineage cells that have undergone neoplastic transformation, making it a useful marker in diagnosis and treatment of B cell derived lymphomas and leukemias, including non-Hodgkin's lymphoma (NHL), acute lymphocytic leukemia (ALL) and chronic lymphocytic leukemia (CLL).

We have generated a fully human antibody to CD19 (MDX-1435) in transgenic mice for high binding affinity as well as the ability to rapidly internalize for drug delivery. The antibody was conjugated to a potent DNA alkylating agent related to Duocarmycin (MED-2460). This ADC (MDX-1206) shows anti-tumor activity in established Raji, Daudi and Ramos subcutaneous xenograft models at doses as low as 0.1 μmole/kg with no associated weight loss, or other overt toxicity. Efficacy was substantially superior to that of MDX-1435 and non-specific control antibody conjugates.

In addition, MDX-1435 binds to cynomologus monkey CD19 with similar affinity and tissue distribution as in humans. The intravenous administration of two doses at 0.4 μmole/kg was well tolerated in cynomologus monkeys and did not result in overt clinical or histological signs of toxicity.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2452.
Abstract 2465: Gene expression, phenotypic and karyotypic analyses of stepwise prostate carcinogenesis in vitro
Authors: Ke Xi-Song , Li Wen-Cheng , Qu Yi , Hovland Randi , Liu Run-hui , Rotter Varda , Akslen Lars A. , Oyan Anne Margrete , Kalland Karl-Henning
Published: February 2011

The loss of epithelial characteristics and the acquisition of a migratory phenotype, referred to as epithelial to mesenchymal transition (EMT), is a crucial event in tumor metastasis. Our previous work reported an EMT model based on primary prostate epithelial cells (EP156T) which gave rise to mesenchymal cells (EPT1) without malignant transformation. To achieve transformed prostate cells, EPT1 cells were kept growing in extended saturation density cultures to select for cells overriding quiescence. Following about 30 subconfluent passages and thereafter, foci appeared repeatedly in EPT1 monolayers following three to four weeks in confluent cultures. For comparison, in parallel experiments foci appeared neither in confluent cultures of EPT1 cells of early passage nor in confluent EP156T cells of either low or late passages.

Cells from the foci of EPT1 monolayers formed robust colonies in soft agar suggesting full malignant transformation. The transformed cells were named EPT2. In this stepwise transformation model, EPT2 cells showed much higher abilities to proliferate at confluence, migrated better, were less dependent on exogenous growth factors and were more resistant to staurosporine induced apoptosis than EP156T and EPT1 cells. Also, while EP156T cells and EPT1 cells remained diploid, chromosomal instability and aneuploidy were evident in EPT2 cells. Gene expression profiling and western blots showed progressive down-regulation of CDH1 from EP156T, through EPT1 to EPT2 together with a number of additional changes. Our findings provide a novel stepwise transformation model according to which EMT can occur independently of transformation, but is associated with subsequent malignant transformation in prostate carcinogenesis.

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

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2465.
Abstract 2470: Clinically used selective aldosterone blocker attenuates hepatocarcinogenesis via angiogenesis inhibition in rats
Authors: Noguchi Ryuichi , Yoshiji Hitoshi , Ikenaka Yasuhide , Kaji Kosuke , Shirai Yusaku , Fukui Hiroshi
Published: February 2011

Hepatocellular carcinoma (HCC) is now a major health problem. Since the high-risk group of either primary or secondary HCC development seems to be clearer than in the other types of tumors, it is likely that chemopreventive agents will be beneficial in improving the prognosis of HCC. In addition to assessment of tumor growth, recent studies have demonstrated that angiogenesis plays a pivotal role in the hepatocarcinogenesis process. Although several anti-angiogenic agents have already been employed in the clinical practice, most patients show adverse reactions with new drugs. An alternative approach may be to find a clinically available compound that also exhibits anti-angiogenic activity for which the safety of long-term administration has been proven. We previously reported that angiotensin-II (AT-II) was a prerequisite for hepatocarcinogenesis. Suppression of AT-II by angiotensin-converting enzyme inhibitor attenuates hepatocarcinogenesis via-suppression of neovascularization in the clinical practice. Recent studies have also suggested possible involvement of aldosterone (Ald) in neovascularization. The aim of our current study was to elucidate the effect of the clinically used eplerenone, a selective Ald blocker (SAB), on the rat hepatocarcinogenesis especially in conjunction with angiogenesis. We employed the rat hepatocarcinogenesis model, induced by feeding the rats on a choline-deficient, L-amino acid-defined diet without any carcinogen (CDAA model). The effects of SAB on the development of liver enzyme (namely, the placental form of glutathione-S-transferase (GST-P))-altered pre-neoplastic lesions and angiogenesis were examined. We also performed an in-vitro study to elucidate the possible mechanisms involved. Treatment with SAB markedly inhibited GST-P-positive lesions along with suppression of neovascularization. The hepatic vascular endothelial growth factor (VEGF) was also significantly attenuated. Our in-vitro study showed that Ald augmented both proliferation and tubule formation of the endothelial cells, and that SAB inhibited both activities in a dose-dependent manner via inhibition of phosphorylation of the extracellular signal-regulated kinase 1/2. These results indicated that, as well as AT-II, Ald plays a pivotal role in hepatocarcinogenesis, and that augmentation of angiogenesis is involved. Since SAB is already widely used in the clinical practice with proved safety, this drug may represent a potential new strategy for chemoprevention against HCC in the future.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2470.
Abstract 2472: The role of aging T-cells in prostate cancer development
Authors: Angulo Alejandra De , Jolly Christopher A. , Faris Robert , Cavazos David , Salcedo Ramona , Apte Shruti , Chen Cindy , deGraffenried Linda A.
Published: February 2011

As men age past 40, their chance of developing prostate cancer increases exponentially each year. The mechanism by which age influences the risk of prostate cancer remains largely unknown, hindering the development of effective preventive interventions. As one ages, there are significant changes in immune response regulation and outcome. This includes an age-related loss of appropriate T cell function. This loss of appropriate T cell function is associated with a change from anti-inflammatory to pro-inflammatory cytokine production as well as decreased appropriate immune surveillance. We hypothesize that one mechanism by which age increases the risk for prostate cancer may be through these alterations in immune response by the T cells. To date, the specific contribution of an aging immune system to prostate cancer initiation and progression has been difficult to determine because of the lack of appropriate model systems to evaluate this phenomena. We have recently begun studies investigating the contribution of an aging T cell population to prostate cancer progression using a highly unique and innovative animal model, the glycerol-3-phosphate acyltransferase-1 (GPAT-1) knock out mouse. The GPAT-1 KO young mouse has a T cell phenotype which mimics old wild type mice. We have recently initiated a series of in vitro studies to evaluate the effects of exposure of sera from GPAT KO mice on pro-inflammatory signaling in LNCaP prostate cancer cells. Exposure to sera from young GPAT KO mice resulted in strong induction of NF-κB activity in LNCaP cells compared to both the sera from the age-controlled wild type mice and the sera-free conditions. We are currently evaluating the significance of this NF-κB induction as well as the induction of other pro-inflammatory pathways by the GPAT KO mouse sera in promoting a more aggressive phenotype in our cancer cells. Additionally, LNCaP cells exposed to conditioned media from stimulated T-cells from the GPAT KO mice demonstrated induction of Akt phosphorylation. Previous studies have shown an important role for NF-kB and Akt in promoting inflammation and survival in prostate cancer cells. Currently, we are evaluating how GPAT KO mouse sera might promote a more aggressive phenotype in LNCaP prostate cancer cells. These studies would be the first to demonstrate a specific modulation of prostate cancer signaling by sera from mice that directly reflect an aging T cell phenotype suggesting that age-related loss of appropriate T cell function might contribute to the increased risk for prostate cancer in the elderly.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2472.
Abstract 2473: Effects propolis on inflammation-related rat colon carcinogenesis induced by DMH and DSS
Authors: Obo Yumi , Sokuza Yui , Wei Min , Kakehashi Anna , Tei Keiko , Wanibuchi Hideki
Published: February 2011

Propolis has been reported to have anti-inflammatory, anti-oxidative and anti-tumor effects. The purpose of the present study is to evaluate the effects of propolis on inflammation-related rat colon carcinogenesis induced by 1,2-dimethylhydrazine (DMH) and dextran sodium sulfate (DSS). Six week-old F344 males rats were divided into 3 groups of 20 rats each. All rats were given subcutaneous injections of DMH at dose of 40 mg/kg/b.w. twice in the first week, and followed by 1% DSS in drinking water for 1 week. After 1 week of DSS treatment, groups of rats were fed diet containing 1% ethanol-extracted propolis (EEP), 1% water-extracted propolis (WEP) or basal diet for 29 weeks. The average numbers of Tubular adenocarcinoma were 2.2 ± 3.5, 0.4 ± 0.6 and 1.2 ± 1.7/rat in basal diet group, EEP and WEP groups, respectively. There were significant difference in the number of Tubular adenocarcinoma between basal diet group and EEP or WEP groups. The present research indicated that EEP exerts suppression effect on inflammation-related rat colon carcinogenesis induced by DMH and DSS.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2473.