bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 3252: Potent Aurora kinase inhibitors based on a pyrimidine scaffold: Synthesis, SAR and X-ray crystallography studies
Authors: Luo Yunting , Martin Mathew , Kendig Robert , Pireddu Roberta , Yang Hua , Betzi Stephane , Books Wesley , Yu Huidong , Schonbrunn Ernst , Lawrence Nicholas , Cheng Jin , Sebti Said , Lawrence Harshani
Published: June 2012

Aurora kinases belong to the serine/threonine subclass of kinases involved in the regulation of mitosis. Out of the three isoforms of Aurora kinases; Aurora A, B and C, studies have shown Aurora A and B are up-regulated in many cancers including breast and colorectal cancers. Deregulated Aurora kinase activity has been linked to genetic instability, defects in centrosome function, spindle assembly, chromosome alignment and cytokinesis, all of which can lead to tumorigenesis. Inhibition of Aurora kinase A and B is emerging as target-based therapy in cancer treatment. HLM-8598 was identified from our in-house chemical library as a potent and highly selective inhibitor for Aurora A (IC50 value of 0.073 ± 0.002 μM) over Aurora B (IC50 = 5.4 ± 1.8 μM). HLM-8598 with pyrimidine scaffold represents 3-4 points of diversity for focused library synthesis. X-ray crystallography studies of HLM-8598 bound to Aurora A confirmed HLM-8598 is a type-1 kinase inhibitor that interacts with the ATP binding site of the enzyme. Synthetic modifications around HLM-8598 and focused library synthesis was carried out to explore structure activity relationship studies. The HLM-8598-Aurora A structure assisted the generation of new analogs with improved affinity (IC50 = 40 nM). The synthesis of HLM-8598 analogs, structure activity relationship studies along with X-ray crystallography will be discussed as a part of our efforts to identify Aurora kinase inhibitors. We will discuss the use of kinase structural elements to rationally guide compound synthesis and improve design strategy. The activity of this class of compounds in cells and animal models will be discussed as Aurora inhibitors as potential anti-cancer agents.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3252. doi:10.1158/1538-7445.AM2011-3252
Abstract 326: Investigation of molecular subtypes within FFPE breast cancer tumors using the Breast Cancer DSA®
Authors: Deharo Steve , Mulligan Jude M. , McDyer Fionnuala A. , Bylesjo Max , Halfpenny Iris , Delaney Thomas , Quinn Jennifer E. , Couch Fergus J. , Proutski Vitali , Harkin Paul D. , Kennedy Richard D.
Published: June 2012

Microarray gene expression profiling has facilitated identification of molecular subtypes which can be associated with disease outcome and treatment response. However current platforms lack disease focus, potentially missing vital information contained in patient tissue samples. Moreover, a wide range of FFPE sample cohorts are available but their use is limited by the mRNA degradation inherent to the sample fixation process.

By combining the Breast Cancer DSA® with powerful data analysis methodology, we reproduced the five major molecular subtypes in breast cancer based on a cohort of 107 FFPE samples. Furthermore, we showed that the established subtypes do not extend to BRCA1 and BRCA2 mutant tumours, necessitating expansion of the original breast cancer subtypes definition.

Following RMA pre-processing of the 107 raw profiles, the data was transformed to overcome the association between profile quality and expression variability. If left untreated, this technical variability, often observed with FFPE tissues, can impair the study of inherent biological variations. Using the intrinsic list of 277 genes previously identified as differentiating breast cancer subtypes in fresh frozen samples [Sorlie et al., 2003], initially the sporadic samples were examined using hierarchical agglomerative clustering. All five original subtypes were identified, verifying the ability to detect subtypes in FFPE samples using the breast cancer DSA®. When the intrinsic list was applied to all 107 samples including BRCA1 and BRCA2 mutant samples, the subtypes were still distinguishable, although 31% of the mutant tumors were unclassified suggesting that specific biological processes defining BRCA1/BRCA2 mutant tumours are not captured by the original breast cancer molecular classification.

We have successfully overcome the limitation imposed by FFPE sample microarray profiling by using the Breast Cancer DSA® and advanced data manipulation and exploration to reproduce molecular subtypes previously identified using fresh frozen samples. Further investigation to extend the previously identifed subtypes will progress the investigation of the heterogeneous biology underlying breast cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 326. doi:10.1158/1538-7445.AM2011-326
Abstract 3298: Structure-based computer-aided drug design to discover novel small molecules that target brain tumor stem cells
Authors: Gu Chunyu , Mahasenan Kiran V. , Auvil Tyler , Joshi Kaushal , Gupta Snehalata , Mattson Anita , Li Cheng , Nakano Ichiro
Published: June 2012

INTRODUCTION. Malignant glioma is one of the most lethal diseases in adulthood and remains refractory to the current therapies including chemoradiotherapies. The cancer stem cell theory dictates that brain tumor stem-like cells (BTSC) account for such intractability of malignant glioma. Recently, several molecularly-targeted therapies have demonstrated a varying degree of success in treatment of cancers including leukemia and breast cancer. In this study, we sought to determine the key kinases that regulate survival, self-renewal, and proliferation of BTSC, and to design novel small molecules by using the structure-based computantional modeling system.

RESULTS. With the neurosphere cultures derived from our glioma patients, we identified 3 kinases that play vital roles in survival and/or proliferation of BTSC in vitro; Fibroblast Growth Factor Receptor 1, Aurora kinase B, and Maternal Embryonic Leucine-zipper Kinase. Structure-based computational modeling allowed us to perform in silico docking of various small molecule candidates to these kinases. As a result, four novel small molecules demonstrated highly specific targeting of the key structural elements of these kinases. We then synthesized these identified candidate compounds and confirmed their in vitro inhibition of the targeting kinase activities. Finally, we will also present our data about the treatment effect with these compounds on the in vitro BTSC growth and the in vivo tumor growth.

CONCLUSION. Structure-based drug design will likely open up a new avenue to discover novel anti-cancer stem cell agents that can selectively target the key kinases in BTSC, leading to the growth arrest of malignant glioma.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3298. doi:10.1158/1538-7445.AM2011-3298
Abstract 33: Microarray analysis of zeranol induced gene expression in primary cultured human breast cancer epithelial cells
Authors: Ye Weiping , Xu Pingping , Zhong Saiyi , Lin Shu-Hong , Liu Jie-Yu , Lin Young C.
Published: June 2012

Zeranol (Z) is a nonsteroidal mycotoxin with potent estrogenic activity. Z is one of six growth promoters approved by the FDA for use in the U.S. beef industry to accelerate weight gain, improve feed efficiency and increase the lean meat-to-fat ratio. Recently, the safety meat products from Z-implanted beef has been questioned on the basis that increased exposure of bioactive Z residues may have adverse health implications. Our previous study showed that serum, meat and meat extracts derived from beef cattle implanted with Z significantly stimulated the proliferation of primary cultured human normal and cancerous breast epithelial cells, primary cultured human breast pre-adipocytes, and human breast cancer cell lines. However, little is known about the mechanisms of Z stimulation on the growth of different types of breast cells. To systematically investigate gene expression patterns in primary cultured human breast cancer epithelial cells (PCHBCECs) after Z treatment, we performed DNA microarray analysis. After PCHBCECs were isolated from breast cancer tissue, they were treated with 30 nM Z or 0.1% DMSO, as a vehicle control, for 48 hr, and then mRNA was isolated and purified for gene expression analysis using the Human Genome U133 Plus 2.0 Array TM (Affymetrix Co. Ltd) in the Microarray Shared Resources at The Ohio State University Comprehensive Cancer Center. DNA microarray data were generated on the basis of the criteria of signal intensity and signal ratio. Our results showed that 10 genes were down-regulated and 25 genes were up-regulated in PCHBCECs treated with 30 nM Z as compared to the controls. Among the genes regulated by Z were, limb-bud and heart (LBH) and annexin-1 (ANXA1) which were decreased 2.27 and 2 fold, respectively and human HMG-CoA synthase 1 (HMGCS1) and methyltransferase like 7A (METTL7A) which were up-regulated to 3.8 and 3.25 fold, respectively compared with the controls. Our preliminary data also showed that Z decreased the expression of several tumor suppressor genes, such as protein tyrosine phosphatase γ (PTPγ), p16, p21, and increased DNMT1 expression in PCHBCECs which suggests epigenetic modification of Z in their promoter regions. Our results indicate that long term consumption of beef products with low level of Z or its metabolites might have adverse health effects on human breast. Further validation of our DNA microarray results is in progress in our laboratory (Supported by NIH R01Grant ES 015212).

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 33. doi:10.1158/1538-7445.AM2011-33
Abstract 3324: Evidence for label-retaining tumor initiating cells in human glioblastoma
Authors: deleyrolle Loic P. , Harding Angus , Cato Kathleen , Siebzehnrubl Florian , Rahman Maryam , de Assis Denis , Azari Hassan , Olson Sarah , Gabrielli Brian , Osborne Geoffrey , Vescovi Angelo , Reynolds Brent
Published: June 2012

Individual tumor cells display diverse functional behaviors in terms of proliferation rate, cell-cell interactions, metastatic potential and sensitivity to therapy. Moreover, sequencing studies have demonstrated surprising levels of genetic diversity between individual patient tumors of the same type. Tumor heterogeneity presents a significant therapeutic challenge as diverse cell-types within a tumor can respond differently to therapies, and inter-patient heterogeneity may prevent the development of general treatments for cancer. One strategy that may help overcome tumor heterogeneity is the identification of tumor subpopulations that drive specific disease pathologies for the development of therapies targeting these clinically relevant subpopulations. Here we have identified a dye-retaining brain tumor population that displays all the hallmarks of a tumor-initiating subpopulation. Using a limiting dilution transplantation assay in immuno-compromised mice, label-retaining brain tumor cells display elevated tumor initiation properties relative to the bulk population. Importantly, tumors generated from these label-retaining cells exhibit all the pathological features of the primary disease. Together, these findings confirm dye-retaining brain tumor cells as drivers of tumor initiation and therefore viable targets for the development of therapeutics targeting this subpopulation.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3324. doi:10.1158/1538-7445.AM2011-3324
Abstract 3325: Phenotypic heterogeneity and distribution of human glioblastoma tumour-initiating cells
Authors: Piccirillo Sara GM , Watts Colin
Published: June 2012

In the last years the idea that tumours arise from a sub-population of cells endowed with “stem cell” features completely revolutionized the field of Oncology. This hypothesis found its initial confirmation by studies on non-solid tumours and then has been extended also to solid tumours. It is a common believe that the so called “cancer stem cells” concept could also provide new insights into the cellular and molecular mechanism of tumour growth and to the development of new therapeutic strategies for the treatment of incurable cancers.

The most lethal tumour of the Central Nervous System is Glioblastoma Multiforme (GBM) which accounts for over 60% of brain tumours. Median life expectancy in optimally managed patients is only 12-14 months with only 25% surviving 24 months. The current clinical management of patients diagnosed with a GBM involves a combination of surgery, radiotherapy and chemotherapy. Radiotherapy has been the principle therapeutic modality since the late seventies and additional targeted chemotherapy is of only modest benefit. Thus the need for new treatments is an unmet clinical need.

It is hypothesized that “cancer stem cells” are a significant factor in gliomagenesis and in the emergence of treatment resistant clones in GBM. However, it is not known how these cells contribute to the heterogeneity of this process.

Here we report the isolation and genetic characterization of distinct “cancer stem cell” populations from different areas of the same GBM specimens: margin, necrotic and core mass. Our results demonstrated that only the cells derived from the core mass retain stem cell features, such as clonogenicity and multipotency, and possess long-term self-renewal and tumour-initiating capacity, therefore can be considered as bona fide “cancer stem cells”. On the contrary, cancer stem cells are rarely found in the other areas.

Most importantly, cells derived from margin areas are not endowed with migratory ability and are genetically aberrant, displaying patterns of karyotypic alterations that overlap only partially with those present in core mass cells. This approach could help us in increasing our understanding of the heterogeneity of cell populations in human GBM in relation to the concept of a stem cell hierarchy in tumours.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3325. doi:10.1158/1538-7445.AM2011-3325
Abstract 3340: Expansion of human breast cancer stem /progenitor cell subpopulation through histone deacetylase inhibitors
Authors: Debeb Bisrat G. , Lacerda Lara , Xu Wei , Robertson Fredika , Ueno Naoto T. , Lucci Anthony , Reuben James M. , Buchholz Thomas A. , Woodward Wendy A.
Published: June 2012

We recently demonstrated that valproic acid, an histone deacetylase (HDAC) inhibitor, radiosensitized breast cancer cells grown on plastic with serum while it radioprotected cells grown in stem cell promoting culture conditions (Debeb et al., 2010) and recently, it has been shown that differentiated cancer cells can de-differentiate into the cancer stem cell phenotype (Meyers et al., 2009; Gupta et al., 2009). Based on these data, we hypothesized that HDAC inhibitors can increase the cancer stem cell population via dedifferentiation of differentiated cancer cells. To examine our hypothesis, Sum159 breast cancer cells were FACS-sorted based on ALDH activity and subsequently treated with one of two known HDAC inhibitors, valproic acid or SAHA. After sorting, ALDH-negative cells were treated either with valproic acid, SAHA, or vehicle. After a week, the percentage of ALDH-positive cells (passage 0, P0) was examined with flow cytometry while the remaining cells were passaged and incubated with and without valproic acid or SAHA for a week and the percentage of ALDH-positive cells again evaluated (P1). This was repeated for the third time (P2). Samples from each generation were also used to assay for, mammosphere formation efficiency, cell cycle analysis as well as to assess RNA and protein expression. In P0 cells, a 3-fold increase in ALDH positive cells was seen in valproic acid-treated cells (35.6% vs.12.6%) and a 1.5-fold increase in SAHA-treated cells (41% vs. 28%) compared to vehicle-treated controls. Moreover, HDAC inhibitors significantly increased primary and secondary mammosphere formation by 3.1 to 13.4-fold. Also, while the percentage of cells in the G0/G1 phase is increased with treatment, the percentage of cells in the S-phase of the cell cycle is significantly reduced. These effects were maintained through multiple passages. Furthermore, the mRNA and protein expression of Beta-catenin and EMT associated genes like vimentin, fibronectin and n-cadherin was significantly increased with treatment in initial and passaged cells. Further functional endpoint studies are being conducted in-vivo to validate these findings.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3340. doi:10.1158/1538-7445.AM2011-3340
Abstract 3364: Upregulation of sonic hedgehog contributes to TGF-β1-induced epithelial to mesenchymal transition in NSCLC cells
Authors: Maitah Ma'in Y. , Ali Shadan , Ahmad Aamir , Gadgeel Shirish , Sarkar Fazlul H.
Published: June 2012

Background: Lung cancer especially non-small cell lung cancer (NSCLC) is the major cause of cancer-related deaths in the United States, and the aggressiveness of NSCLC has been shown to be associated with the acquisition of epithelial-to-mesenchymal transition (EMT). The acquisition of EMT phenotype induced by TGF-β1 in several cancer cells has been implicated with tumor aggressiveness and resistance to conventional therapeutics; however, the molecular mechanism of EMT and tumor aggressiveness in NSCLC remains unknown.

Methodology/Principal Findings: In this study, we found, for the first time, that the induction of EMT by chronic exposure of A549 NSCLC cells to TGF-β1 (A549-M cells) led to the up-regulation of sonic hedgehog (Shh) both at the mRNA and protein levels causing activation of hedgehog signaling. Induction of EMT was found to be consistent with aggressive characteristics such as increased clonogenic growth, cell motility and invasion. The aggressiveness of these cells was attenuated by treatment of A549-M cells with pharmacological inhibitors of Hh signaling in addition to Shh knock-down by siRNA. The inhibition of Hh signaling by pharmacological inhibitors led to the reversal of EMT phenotype as confirmed by the reduction of mesenchymal markers such as ZEB1 and Fibronectin, and induction of epithelial marker E-cadherin.

Conclusions/Significance: These results suggest that transcriptional up-regulation of Shh signaling is mechanistically associated with TGF-β1 induced EMT phenotype, and thus the inhibitors of Shh signaling could be useful for the reversal of EMT phenotype, which would inhibit the metastatic potential of NSCLC cells and also make these tumors more sensitive to conventional therapeutics.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3364. doi:10.1158/1538-7445.AM2011-3364
Abstract 3383: Hepatocyte growth factor upregulation and signaling is associated with carcinogenesis and mesenchymal characteristics in hepatocellular carcinoma
Authors: Ogunwobi Olorunseun O. , Liu Chen
Published: June 2012

Advanced hepatocellular carcinoma (HCC) is an important cause of cancer mortality worldwide. Epithelial-mesenchymal transition (EMT) has been shown to be an important biological process in cancer progression and metastasis. We have focused on elucidating factors that may induce EMT to promote carcinogenesis and subsequent metastasis in HCC using the BNL CL.2 (BNL) and BNL 1ME A. 7R.1 (1MEA) cell lines. BNL cells are normal hepatocytes whereas the 1MEA cells are HCC cells derived from transformation of the BNL cells. Their morphological characteristics were examined. Expression levels of hepatocyte growth factor (HGF), markers of EMT and mediators of HGF signaling were determined in the cell lines and their functional characteristics were compared. BNL cells were treated with HGF and effects on EMT-marker and mediators of HGF signaling were analyzed. BNL cells display characteristic epithelial morphology whereas 1MEA cells display mesenchymal characteristics when examined following H&E staining. qPCR revealed that 1MEA cells express more HGF (200-fold) than BNL cells and confirmed by immunoblotting. There was associated decreased expression of E-cadherin, albumin, AAT and increased expression of fibronectin, collagen-1 and vimentin. There was also increased expression of COX-2, ERK, Akt, phosphorylated ERK and Akt and 1MEA cells formed numerous colonies in soft agar unlike BNL cells. Treatment of BNL cells with HGF led to decreased expression of E-cadherin and increased expression of fibronectin, vimentin, increased migration and increased expression of COX-2, ERK and Akt. We conclude that development of HCC is associated with upregulation of HGF which promotes the acquisition of morphological and molecular mesenchymal characteristics, carcinogenesis and upregulation of COX-2, ERK, Akt and phosphorylated ERK and Akt. Consequently, HGF signaling may be targeted for therapy in advanced and metastatic HCC.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3383. doi:10.1158/1538-7445.AM2011-3383
Abstract 3388: DDX5 modulates Notch signaling via interaction with the MAML1 co-activator and is required to optimal Notch signaling in leukemic cells
Authors: Tian Liang , Lin Shuibin , Gu Yumei , Chen Zirong , Shen Huangxuan , Wu Lizi
Published: June 2012

Notch receptor-mediated signaling is essential for embryonic development and adult tissue homeostasis by regulating cell proliferation, differentiation and survival. Aberrant Notch signaling is linked to many epithelial cancers and hematological malignancies. For example, activated NOTCH1 mutations are detected in more than 50% of T cell acute lymphoblastic leukemia (T-ALL) patients. Since the constitutive activation of Notch signaling results in leukemic cell transformation and is required for the maintenance of the leukemic phenotype, the Notch pathway is a promising and highly specific molecular therapeutic target for T-ALL.

We have previously identified the family of the MAML transcriptional co-activators as essential components of the core Notch transcription activation complex. The prototypic member MAML1 was found to be the major co-activator that regulates NOTCH1 oncogenic activities in leukemic cells. Hence, the modulation of MAML1 expression levels or functional activities is expected to affect Notch-induced leukemic initiation and progression. However, it remains unclear how MAML1 function is regulated. To gain insights into the molecular basis underlying MAML1 function, we undertook the task of identifying cellular factors that interact with MAML1 and characterizing their roles in regulating Notch signaling and Notch-mediated T cell leukemia. Through proteomic studies, we identified DDX5, an ATP-dependent DEAD-box RNA helicase, as a component in the MAML1 protein complex. Given the role of DDX5 as a transcriptional modulator, we reasoned that DDX5 might be a critical regulator of MAML1-mediated Notch target genes transcription. We showed that DDX5 interacts with MAML1 in vitro and in vivo, and is associated with the endogenous Notch1 transcription activation complex through interaction with MAML1. Lentiviral-mediated shRNA knockdown of DDX5 resulted in decreased expression of Notch target signature, along with reduced cell proliferation and survival in leukemic cells that carry activated NOTCH1 mutations. Our findings thus revealed an essential role of DDX5 in promoting efficient Notch-mediated transcription in leukemic cells where the Notch pathway is constitutively activated, suggesting that DDX5 might be critical for Notch-mediated T-ALL pathogenesis and could be a potential new target for modulating the Notch signaling in leukemia.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3388. doi:10.1158/1538-7445.AM2011-3388
Abstract 3402: Up-regulation and invasive role of MUC18/MCAM in glioma sphere culture
Authors: Shimizu Keiji , Ishida Eri , Kawanishi Yu , Tamura Masakazu , Yawata Toshio
Published: June 2012

Glioblastomas are characterized by aggressive invasion into normal brain tissues, thus limiting complete removal by surgical resection resulting in recurrence. Our identified molecule involved in glioma invasion is important for developing targeted effective therapies in the malignant glioma. Cancer stem cells are capable for self-renewing and are thought to be responsible for tumor metastasis and dissemination. However, the invasive activities of cancer stem cells have not been fully understood. To investigate a role of glioma stem cells in the tumor invasion, tumor sphere culture was established from mouse glioma RSV-M cells. The high tumorigeneity and aggressive migration of RSV-M tumor sphere were observed in intracranial transplantation. Quantitative RT-PCR analysis showed the enhanced expression of metastasis-related genes in RSV-M tumor sphere. Of these, MUC18/MCAM also highly expressed in tumor sphere derived from human glioma cell lines. Importantly, CD133-positive fraction of glioma sphere culture isolated from glioblastoma patients contained a cell population expressing MUC18 but CD133-negative fraction not. To examine a function of MUC18 in glioma cells, the expression or knockdown construct for the gene were introduced into human glioma cells. Over-expression of MUC18 in the glioma cells increased their invasive capacity and clonogenicity in comparison to the parent or knockdown cells. In addition, expression of some metastasis-related genes was up-regulated in MUC18-over-expressing cells. These results suggest that enhanced MUC18 expression of glioma stem cells may contribute to the aggressive invasion of this tumor.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3402. doi:10.1158/1538-7445.AM2011-3402
Abstract 3435: Proteomic analysis of changes to the cellular kinome in the epithelial to mesenchymal transition
Authors: Tanowitz Michael , Bean James , Haley John D. , Garton Andrew
Published: June 2012

The epithelial to mesenchymal transition (EMT) is a developmental program characterized by loss of cell-cell contacts, loss of cell polarity, and acquisition of a migratory phenotype. Many of the hallmarks of EMT correspond to aspects of carcinogenesis, particularly with regard to metastasis and invasion, and EMT is associated with the development of tumor cell resistance to EGFR inhibitors. We have applied proteomic approaches to examine changes to the cellular kinome in response to various EMT-inducing ligand treatments. For our studies we chose the H358 NSCLC line after week-long single or combination treatments with Hepatocyte Growth Factor (HGF), Transforming Growth Factor Beta (TGFβ) and Oncostatin M (OSM). We used several approaches to probe for changes following EMT using mass spectroscopy: whole cell lysate fractionation to provide an unbiased overview of cellular proteins, affinity isolation of cellular phospho-proteins, and targeted analysis of ATP binding proteins (KinativTM). Using these methods we have identified a host of protein changes that are clustered across several signaling pathways and cellular functions. Among these are changes in receptor tyrosine kinases centered around phylogenetically related groupings such as Tyro3/Mer/Axl and Ron/Met, concerted changes in actin-dependent motor proteins consistent with changes in migratory behavior, and changes indicative of reorganization of calcium signaling networks. Functional consequences of these changes and their potential to inform therapeutic interventions will be discussed.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3435. doi:10.1158/1538-7445.AM2011-3435
Abstract 3439: Sarcomatoid renal cell carcinoma as a biological example of epithelial to mesenchymal transition (EMT)
Authors: Boström Anna-Karin , Möller Christina , Nilsson Elise , Axelson Håkan , Johansson Martin E.
Published: June 2012

About 8% of clear cell renal cell carcinoma (CCRCC) cases contain areas of a radically different morphology, demonstrating spindle shaped cells and a histological resemblance to sarcomas. These biphasic neoplasms are called sarcomatoid CCRCC (sCCRCC). Patients diagnosed with sCCRCC face a considerably worse prognosis due to an increased propensity for metastasis. Using a set of biphasic CCRCC cases, we showed that sCCRCC has a higher proliferative index and more prononced vimentin expression as compared to the CCRCC counterpart. We selected a CCRCC/sCCRCC case demonstrating overgrowth as well as metastatic spread for extended immunohistochemical characterization. Using mouse xenografts we evaluated a $$$$CCRCC cell-line and put forward the hypothesis that some CCRCC cell-lines may be derived from the sarcomatoid component rather than from the clear cell part, with obvious implications for the validity of in vitro models of CCRCC. We confirm that sCCRCC is derived from the clear cell component and show that sCCRCC morphologically and immunohistochemically may represent a completed epithelial mesenchymal transition (EMT). Furthermore we suggest that TGF-β1 may be the driving force behind sarcomatoid transdifferentiation i.e. EMT in CCRCC.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3439. doi:10.1158/1538-7445.AM2011-3439
Abstract 345: The intratumoral Wnt2B expression affects tumor progression in malignant pleural mesotheliomas
Authors: Kobayashi Masashi , Huang Cheng-long , Miyahara Ryo , Sonobe Makoto , Menju Toshi , Kikuchi Ryutao , Ishikawa Masashi , Kitamura Jiro , Iwakiri Shotaro , Itoi Kazumi , Date Hiroshi
Published: June 2012

Introduction: Malignant pleural mesotheliomas are aggressive tumors with a poor prognosis. It is considered to be important to identify the molecular targets for the treatment against malignant pleural mesotheliomas. We have recently found the Wnt1 expression to affect tumor progression in non-small cell lung cancers, through the induction of various Wnt-targets (Huang et al, Eur J Cancer 2008). Therefore, we performed a clinical study on the intratumoral expressions of the canonical Wnts, such as Wnt1 and Wnt2B, in relation to their targets, including c-Myc and survivin. Methods: Sixty-five cases with malignant pleural mesotheliomas were investigated. Immunohistochemical assays were performed to evaluate the intratumoral expressions of Wnt1, Wnt2B, c-Myc and survivin. In addition, the Ki-67 proliferation index was evaluated by immunohistochemistry, and the apoptotic index was evaluated by the TUNEL method. Results: The Ki-67 proliferation index was significantly higher in c-Myc-high tumors than in c-Myc-low tumors (P=0.008). In addition, the Ki-67 proliferation index was also significantly higher nuclear-survivin-high tumors than in nuclear-survivin-low tumors (P=0.004). Regarding the intratumoral expressions of canonical Wnts, 18 tumors (27.7%) were Wnt1-high tumors, and 36 tumors (55.4%) were Wnt2B-high tumors. The rate of Wnt2B-high tumors was significantly higher than the rate of Wnt1-high tumors (P=0.024). Regarding tumor histology, the Wnt2B expression was the significantly highest in epithelial type (P<0.001). On the other hand, there was no significant difference in the Wnt1 expression according to the tumor histology (P=0.163). Furthermore, the Wnt 2B expression significantly correlated with expressions of c-Myc and survivin (P<0.001 and P<0.001, respectively). The c-Myc expression was significantly higher in Wnt2B-high tumors than in Wnt2B-low tumors (P<0.001), and the survivin expression was also significantly higher in Wnt2B-high tumors than in Wnt2B-low tumors (P=0.007). In contrast, there was no significant difference in c-Myc or survivin expressions according to the Wnt1 expression (P=0.218 and P=0.688, respectively). Conclusions: The intratumoral Wnt2B expression affects tumor progression of malignant pleural mesothelioma through the induction of c-Myc and survivin. The Wnt2B could be a candidate of targets of the molecular therapy against malignant pleural mesotheliomas.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 345. doi:10.1158/1538-7445.AM2011-345
Abstract 3455: Comparison of expression profiles of pediatric high and low grade brainstem gliomas to pediatric supratentorial high grade astrocytomas
Authors: Buczkowicz Pawel , Bartels Ute , Morrison Andrew , Bouffet Eric , Tabori Uri , Hawkins Cynthia
Published: June 2012

Diffuse intrinsic pontine gliomas (DIPG) are one of the most devastating pediatric malignancies and currently the number one cause of brain tumor related death in children with a 10-12 month median survival. Despite this very little is understood about the biology of these tumors. We have already shown potential novel therapeutic targets for DIPG using high-resolution SNP-based analysis. We performed high resolution genetic analysis using whole-genome single-nucleotide polymorphism (SNP) arrays (Affymetrix 500K and 6.0) on post mortem tumor with matched normal brain samples (n=9) and surgical samples (n=2) for a series of DIPG patients as well as pediatric supratentorial high grade astrocytomas (sHGA, n=20). Here we extend our initial study to include expression array analysis, amalgamating the datasets to generate a more complete understanding of the genetic alterations underlying brainstem gliomas. Expression profiling using Illumina HumanHT-12 arrays was conducted on 26 high grade brainstem gliomas, including 23 DIPGs, 51 low grade brainstem gliomas and 30 supratentorial high grade astrocytomas. Expression profiles highlighted the distinctiveness of DIPGs when compared to high grade supratentorial astrocytomas. Analysis resulted in two groups of DIPGs when clustering based on most significant differentially expressed genes (p < 0.005) with one group being more similar to pediatric low grade brainstem gliomas and the other distinct from both the supratentorial high grade tumors and other brainstem gliomas. This data will increase our understanding of brainstem glioma biology, information crucial to the development of agents targeted more specifically towards this devastating disease.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3455. doi:10.1158/1538-7445.AM2011-3455
Abstract 3460: Genome-wide copy number analysis reveals novel somatic mutations associated with choroid plexus tumorigenesis
Authors: Merino Diana M. , Shlien Adam , Pienkowska Malgorzata , Tabori Uri , Malkin David
Published: June 2012

Choroid plexus carcinomas (CPCs) are aggressive pediatric neoplasms accounting for less than 1% of brain tumors, but representing more than 10% of brain tumors in children under 1 year of age. CPCs are frequently observed in the context of the Li-Fraumeni Syndrome (LFS), yet this association has not been fully elucidated. The genetic mechanisms leading to this disease are poorly understood; however, we have recently demonstrated that TP53 status and total structural variation are correlated with tumor subtype and clinical outcome in choroid plexus tumor (CPT) patients, distinguishing between individuals with CPC and choroid plexus papilloma (CPP), a benign tumor with a more favorable prognosis. We set out to characterize genomic regions in which copy number variation and gene expression changes are uniquely associated with CPC tumors in order to identify genes that may serve as markers in tumor diagnosis and prognosis.

DNA and RNA from 59 choroid plexus tumors (CPC, n=29 and CPP, n=30) and two samples of normal choroid plexus tissue were obtained from a multi-institutional tissue and clinical database. We conducted high-resolution copy number alteration (CNA) and gene expression analysis for each tumor sample using highly dense microarrays (Affymetrix SNP 6.0 and Exon 1.0 ST array, respectively). DNA microarray data was segmented using a Hidden Markov Model (HMM) approach. Statistical analysis was carried out using Partek Genomics Suite in which CNAs and gene expression changes between CPC, CPP, and normal choroid plexus samples were contrasted. We identified 14 CPC-unique loci harboring CNAs with corresponding gene expression changes (p>0.05). We observed that CNAs were found at loci where cancer genes with well-characterized oncogenic functions have been previously identified (1p13.2, 1p13.3, 1p21.3, 1p22.1 and 5q13.3). Furthermore, more than 90% of tumors with copy number alterations and expression changes at these five loci also harbored mutant TP53.

These observations suggest involvement of several genes in the malignant progression of CPCs, which may help elucidate the aggressiveness and poor clinical outcome of this tumor subtype compared to the more favorable CPP. Further analysis of CNAs and expression at these loci in the context of TP53 mutations, will provide a more refined genetic profile that will facilitate diagnosis of CPTs and aid in predicting patient outcome.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3460. doi:10.1158/1538-7445.AM2011-3460
Abstract 3467: A novel interplay between Rap1, Epac and PKA regulates induction of angiogenesis
Authors: Menon Jyotsana , Doebele Robert C. , Rosner Marsha R.
Published: June 2012

Advanced stage prostate cancer is associated with poor prognosis since therapeutic options are limited when the disease has progressed into a hormone refractory state. One therapeutic strategy is angiogenesis inhibition, which interferes with the blood supply of the tumor instead of targeting tumor cells directly. Here we focus on the role of three factors as regulators of angiogenesis: Rap1, a small GTPase homologous to Ras; Epac, a cAMP-activated guanine nucleotide factor for Rap1; and Protein kinase A (PKA), a cAMP-activated kinase. In previous studies, we showed that activation of Epac/Rap1 in human microvascular endothelial cells (HMVECs) inhibited VEGF-mediated chemotaxis and angiogenesis in a SCID mouse model of human angiogenesis. To test the efficacy of Epac/Rap1 activation in a prostate tumor xenograft model, we analyzed the effects of constitutive Rap1 or 8 CPT-2Me-cAMP (8CPT), a strong Epac agonist and weak PKA agonist, in PC-3 cells. PC3 cells rank high in expression levels of Rap1. Surprisingly, although 8CPT did not alter tumor growth in PC-3 cells, the drug significantly reduced tumor size in PC-3 cells expressing constitutively active Rap1. Tumor analysis showed an increase in VEGF and CD31 immunostaining in Rap1-expressing tumors, and a significant decrease in their levels upon treatment of the mice with 8CPT. To understand the mechanism of tumor inhibition, we cultured PC-3 cells under hypoxic conditions that mimic the tumor microenvironment. As observed in vivo, constitutive Rap-1 expression induced VEGF and Glut-1 mRNA levels as well as HIF-1α protein, and 8CPT reversed this effect. However, in contrast to HMVECs, 8CPT acts in PC-3 cells via PKA. A PKA activator mimicked 8CPT by inhibiting VEGF secretion in PC3-Rap1 cells under hypoxic conditions. Furthermore, the PKA inhibitor, H-89, reversed the inhibition of VEGF secretion in PC3-Rap1 cells in culture and inhibited growth in mouse xenografts. Thus, expression of Rap1 in PC-3 human prostate tumor cells promotes hypoxic induction of angiogenesis and increases the susceptibility of the cells to PKA inhibition. Taken together, our results suggest that a novel interplay between Rap1, Epac and PKA regulates tumor-microenvironment induction of angiogenesis.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3467. doi:10.1158/1538-7445.AM2011-3467
Abstract 3468: MMP-9 inhibition abolishes hypoxia-induced angiogenesis in medulloblastoma
Authors: Chetty Chandramu , Bhoopathi Praveen , Rao Jasti S. , Lakka Sajani S.
Published: June 2012

Hypoxia-inducible factor-1 (HIF-1) transcription factor is a critical mediator of the hypoxic response and upregulates expression of various proteins that promote angiogenesis and many other survival pathways in cancer. Overexpression of HIF-1α and matrix metalloproteinase-9 (MMP-9) is common in human cancers, including medulloblastoma, and is correlated with a malignant phenotype. Therefore, we investigated the effects of hypoxia-induced MMP-9 on angiogenesis in medulloblastoma cells. Western blotting and immunohistochemical analysis showed that hypoxia enhanced stabilization of HIF-1α and expression of VEGF and MMP-9 in medulloblastoma cells in vivo and in vitro. Further, endothelial tube formation assay in vitro and dorsal air sac assay in vivo showed that hypoxia enhanced angiogenesis in medulloblastoma cells. Transcriptional inactivation of MMP-9 using siRNA (pMMP-9-Si) inhibited hypoxia-induced stabilization of HIF-1α, and induced expression of VEGF and prolyl hydroxylase. Moreover, supplementation of human recombinant MMP-9 in MMP-9-Si-transfected cells restored VEGF expression and angiogenesis. In summary, the results of the present study indicate that MMP-9 upregulation could be an important mediator of tumor hypoxia-induced angiogenesis. Therefore, inhibition of MMP-9 could be an effective therapeutic strategy for the treatment of hypoxic medulloblastoma cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3468. doi:10.1158/1538-7445.AM2011-3468
Abstract 3471: Antibody-directed neutralization of fibrinolytic receptor annexin II inhibits human breast cancer growth in a xenograft model
Authors: Sharma Meena , Blackman Marc , Sharma Mahesh C.
Published: June 2012

The fibrinolytic pathway has long been known to be associated with breast cancer. Plasmin is the major end product of fibrinolytic pathway and is critical for normal physiological functions. The mechanism(s) by which plasmin is generated in breast cancer is not yet fully understood. Previously we identified ANX II, a fibrinolytic receptor, in human breast cancer samples and observed a strong positive correlation with advanced stage of cancer. We further demonstrated that the tissue plasminogen activator (tPA) binds to ANX II in invasive breast cancer MDA-MB231 cells which at least in part responsible for plasmin generation. We hypothesized that ANX II-dependent plasmin generation in breast cancer is necessary to activate the switch for neoangiogenesis thereby promoting aggressive cancer phenotype. Our immunohistochemical studies of human breast cancer tissues demonstrate strong positive correlation between annexin II expression and neoangiogenesis. These data not only indicate a link between ANX II and neoangiogenesis but also suggest that ANX II may be a potential target to slow or inhibit breast cancer growth by inhibiting neoangiogenesis. In this report we show that administration of anti-ANX II antibody potently inhibits the growth of human breast cancer in a xenograft model. Inhibition of tumor growth was due to inhibition of neoangiogenic activity within the tumor. In vitro studies demonstrated that anti-ANX II antibody inhibited angiogenesis on three dimensional matrigel cultures. The inhibition of in vitro angiogenesis was due to endothelial cell (EC) apoptosis. Taken together, these data suggest that selective disruption of fibrinolytic activity of ANX II may be a novel strategy for inhibition of neoangiogenesis in human breast cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3471. doi:10.1158/1538-7445.AM2011-3471
Abstract 3478: Latent KSHV infection increases the vascular permeability of endothelial cells
Authors: Damania Blossom , Guilluy Christophe , Zhang Zhigang , Burridge Keith
Published: June 2012

Infection with Kaposi's sarcoma-associated herpesvirus (KSHV) is closely linked to the development of Kaposi's sarcoma (KS). The KS lesion is driven by KSHV-infected endothelial cells and is highly dependent on autocrine and paracrine factors for survival and growth. We report that latent KSHV infection increases the vascular permeability of endothelial cells. Latent KSHV-infected endothelial cells display increased Src kinase activity, increased Rac1 activation and activation of its downstream modulator, p21 activated kinase (PAK1). The KSHV-infected endothelial cells exhibited increases in tyrosine phosphorylation of VE-cadherin and β-catenin, while total levels of these proteins remained unchanged, suggesting that latent infection disrupted endothelial cell junctions. Consistent with these findings, we found that latent KSHV-infected endothelial cells were more permeable than uninfected endothelial cells. Knockdown of Rac1, as well as inhibition of ROS, resulted in decreased permeability of the KSHV-infected endothelial cells. In sum, KSHV latent infection increases the vascular permeability of infected endothelial cells thereby contributing to the pathogenesis of Kaposi's sarcoma.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3478. doi:10.1158/1538-7445.AM2011-3478