bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract LB-227: Receptor tyrosine kinase phosphorylation: Simultaneous detection of 10 kinases upon inhibitor treatment
Authors: Henzler Tanja , Pohl Stefanie , Schneiderhan-Mara Nicole , Rimmele Stefanie , Livengood April , Kovelman Robert , Herget Thomas 
Published: February 2011

Abstract
Receptor tyrosine kinases have been shown to be major pharmaceutical targets involved in disease states such as diabetes and cancer. Target driven therapeutics like small molecules or monoclonal antibodies are already in clinical use and have tremendous influence on new cancer therapies. In most cases either ligand binding to the extracellular domain followed by receptor dimerization or ATP binding to the intracellular kinase domain is inhibited. However, it is still challenging to gain specificity of those inhibitors for certain receptor tyrosine kinase targets.
Bead-based assay technologies, such as the xMAP® platform, are ideal tools for the multiplex analysis of 5-20 proteins. Low sample volumes, simple assay protocols, flexibility and robustness are characteristics of bead-based assays that make them well suited for the immunological detection of bio marker and cell signaling proteins.
In this presentation we will show results for the simultaneous detection of the ten most relevant receptor tyrosine kinases. The expression profile of more than 50 cell lines as well as breast tumor samples were evaluated with this powerful multiplex tool in a very robust and convenient way. Inhibitor profiling of small molecules under physiological conditions on ten receptor tyrosine kinases will be demonstrated by the detection of their phospho-Tyrosine level. These specificity profiles will help to improve the drug development process and to obtain potentially better drugs in 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 LB-227.
Abstract LB-234: Bcl-2, a novel target of Bmi-1 (the stem cell associated factor), induced Wnt signaling: Implications on prostate cancer
Authors: Saleem Mohammad , Siddiqui Hifzur R. , Tarapore Rohinton S. , Kohl Amanda M. 
Published: February 2011

Abstract
In the current report we provide a novel finding about the regulation of Bcl-2 expression in prostate cancer (CaP) cells. Bcl-2 is known to be regulated by Sonic Hedgehog (SHH) signaling. Here, we provide evidence that human CaP cells exhibit SHH-independent Bcl-2 activation which is regulated by Bmi-1-induced Wnt signaling. Bmi-1 is a member of polycomb group gene family and is reported to be involved in stemness and self-renewal capability of cancer stem cells. We investigated the role of Bmi-1 in human CaP development and delineate its mechanism of action. On the basis of immunohistochemical analysis of prostatic specimens of 125 human CaP patients, we show that Bmi-1 protein levels are highly elevated in patients with advanced disease. To understand the mechanism of action of Bmi-1, we employed two-prong strategy. Firstly, Bmi-1 was knocked down in CaP cells (LNCaP, DU145 and PC-3) by employing siRNA technique. Bmi-1-silenced CaP cells exhibited decreased proliferative and clonogenic potential. Secondly, Bmi-1 was over-expressed in CaP cells by transfecting Bmi-1 overexpressing plasmid (pbabe-Bmi-1) in CaP cells. Bmi-1-overexpressing cells exhibited increased clonogenicity and rate of proliferation. We performed a micro-array analysis of Bmi-1-silenced cells and found that silencing of Bmi-1 caused a decrease in the Cyclin D1 (Wnt signaling target) and Bcl-2 (SHH signaling target), however an increase in p16 was observed. These studies were validated by performing immunoblot analysis. We generated a hypothesis that the Bmi-1 regulates the expression of Cyclin D1 and Bcl-2 by interacting with Wnt /SHH signaling in CaP cells. We show that despite blocking SHH signaling (by treating CaP cells with cyclopamine, a SHH signaling inhibitor), Bmi-1 induces the Bcl-2 expression in CaP cells suggesting the involvement of SHH-independent pathway in the regulation of Bcl-2 activation. We identified Wnt signaling as the pathway that regulates Bcl-2 independent of SHH signaling in CaP cells. We provide evidence that Bcl-2 promoter region of Bcl-2 gene has binding sites for Tcf transcriptional factor (Wnt signaling component). We found that Bmi-1 induces Wnt signaling in CaP cells. Taken together, these studies provide deep-insight into the mechanism of CaP cell proliferation (even after chemotherapy such as cyclopamine treatment). We suggest that Bmi-1 could be developed as a novel molecular and therapeutic target for human CaP treatment.
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 LB-234.
Abstract LB-237: Interaction between myopodin and integrin linked kinase (ILK) induces tumor suppression
Authors: Yu Yanping , Wang Hui , Luo Jian-Hua 
Published: February 2011

Abstract
Myopodin, a tumor suppressor, is frequently deleted in invasive prostate cancers. Forced expression of myopodin in prostate cancer cells reduced tumor invasiveness and slowed cell motility. In our recent yeast two hybrid system analysis, we found that the N- terminal 326 amino acids of myopodin interacts with integrin linked kinase (ILK). This result was validated by co-immunoprecipitation of myopodin or ILK in cells expressing both proteins. In addition, the binding assays between ILK and myopodin were analyzed in vitro on a series of GST-myopodin deletion mutants with ILK. A binding motif of 78 amino acids in the N- terminus of myopodin was determined to be critical for ILK binding. Phosphorylation analyses through ILK knockdown or mutant assays in vivo and in vitro indicate that phosphorylation of myopodin is ILK dependent. Phosphorylation of myopodin by ILK leads suppression of cell motility and cell growth. Mutant myopodin that does not interact with ILK is not phosphorylated and is defective on suppressing cell motility and cell growth. These findings elucidate a novel signaling pathway of ILK-myopodin that leads to activation of a tumor suppressor.
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 LB-237.
Abstract LB-263: Study of Hox gene expression in normal and malignant colonic tissues implicates Hox A4 and Hox D10 in the stem cell-origin of colon cancer
Authors: Bhatlekar Seema 
Published: February 2011

Abstract
Our goal was to identify transcriptional regulatory mechanisms that maintain stem cell (SC) population size in normal colonic epithelium because dysregulation, following acquisition of mutations, leads to tumor SC overpopulation, tumor initiation, and colon cancer. We used microarray analysis to identify a unique gene-expression pattern for a SC-enriched population (the bottom third of the normal human crypt, where colonic SC reside). Two-color microarray analysis (18,500 genes) was used to analyze gene expression in isolated crypt subsections (top [T], middle [M], and bottom [B] thirds). About 25% of known genes were expressed (showed hybridization to RNA from colonic epithelium). Several RNA species (n=287) were preferentially expressed in one of the three crypt subsections (T, M, or B). Six of the known genes up regulated in the bottom third of the crypt mapped to the P13 kinase pathway and two were Hox genes (Hox A4 and D10). Immunohistochemistry (IHC) was then used to analyze expression of Hox A4 and Hox D10 in human colonic tissues. IHC showed that both Hox A4 and D10 are expressed in cells residing at the bottom of the normal crypt and are co-expressed with aldehyde dehydrogenase 1 (ALDH1), a SC marker in these cells. Moreover, IHC showed that Hox A4 and D10 are overexpressed in tumors compared with normal colonic epithelium. These data represent the first gene-expression profiles for sub-regions of the human colonic crypt, especially the SC-rich crypt base, which we now know has a unique gene-expression signature. Co-expression of Hox A4 and D10 with ALDH1 in normal colonocytes suggests that these Hox genes have a role in regulation of the crypt SC population size. Overexpression of Hox A4 and D10 in colon cancer suggests that these Hox genes, when dysregulated, contribute to SC overpopulation and colon tumorigenesis. Identification of the Hox gene-based mechanisms that are involved in the regulation of normal crypt SC population size and in dysregulation of neoplastic SC populations could lead to identification of SC-based targets and ways to develop new, more effective treatments for advanced colon cancers.
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 LB-263.
Abstract LB-271: The biological role of the transcription factor Kaiso in breast tumorigenesis
Authors: Weerawardane Sonali , Daniel Juliet M. 
Published: February 2011

Abstract
Introduction: The canonical Wnt signalling pathway regulates various cellular processes (e.g. proliferation, differentiation, apoptosis) and leads to tumorigenesis when aberrantly activated. -catenin, the key downstream effector in Wnt signalling, translocates to the nucleus upon Wnt pathway activation, and activates target genes involved in tumorigenesis. The transcription factor Kaiso is a novel BTB/POZ (Broad complex, Tramtrak, Bric à brac/Pox virus and zinc finger) zinc finger (POZ-ZF) protein that specifically interacts with the cell adhesion cofactor p120ctn. Recent studies from our lab and others have revealed that Kaiso negatively regulates the canonical Wnt pathway by repressing activation of Wnt/ -catenin target genes. Some studies implicate Kaiso as a tumor suppressor (decreased expression in breast, ovarian and colon tumors), and others implicate Kaiso in tumor initiation (Kaiso-deficient mice are resistant to intestinal cancer). The goal of this study is to elucidate the biological role of Kaiso in breast tumorigenesis using various cellular assays.
Methods: To assess Kaiso's role in breast cancer, Kaiso was misexpressed in MCF7 (human breast adenocarcinoma) cell lines. Stable Kaiso overexpressing and depleted cell lines were generated and assessed for cell proliferation and cell migration using focus formation, wound healing and matrigel invasion assays. Western blot analysis was performed to assess the effects of Kaiso misexpression on p120 and E-cadherin as well as epithelial-mesenchymal transition markers such as N-cadherin, Snail, Twist and Vimentin. The subcellular localization of Kaiso and its putative target genes in vivo was examined using immunohistochemistry (IHC) analysis of matched pairs of human normal and tumor breast tissue.
Results: Focus formation assays revealed increased transformation by cells over-expressing Kaiso, suggesting an oncogenic role for Kaiso in cell culture. Preliminary wound healing and matrigel assays show increased cell motility and migration respectively in Kaiso over-expressing cells compared to parental control cells, thereby suggesting a role for Kaiso in the epithelial-mesenchymal transition. IHC analysis revealed predominant nuclear Kaiso expression in lobular and ductal breast carcinomas in breast tissues. These data support Kaiso's potential role as an oncogene in human 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 LB-271.
Abstract LB-278: BRMS1 promoter methylation correlates with decreased expression of BRMS1 in non-small cell lung cancer
Authors: Nagji Alykhan S. , Liu Yuan , Stelow Edward B. , Stukenborg George J. , Jones David R. 
Published: February 2011

Abstract
Background: Breast cancer metastasis suppressor gene-1 (BRMS1) mRNA and protein expression are significantly decreased in non-small cell lung cancer (NSCLC) cell lines and human NSCLC when compared to normal bronchial epithelial cells and adjacent noncancerous tumor tissue, respectively. We hypothesized that one mechanism through which BRMS1 expression was decreased in NSCLC was through BRMS1 promoter methylation.
Materials and Methods: Human NSCLC BRMS1 promoter methylation was evaluated using methylation-specific PCR and bisulfite sequencing. The effect of methylation on BRMS1 mRNA and protein expression was assessed following treatment with 5-azacitidine, a demethylating agent in NSCLC cell lines. BRMS1 transcriptional activity was assessed using a human BRMS1-luc reporter gene construct cloned by our group. Student's T-Test and Chi-square tests were used to determine significance between variables of two patient populations separated based on tumor histology (squamous cell or adenocarcinoma) and to evaluate the methylation profile between the two tumor histologies. Immunohistochemical analysis for BRMS1 protein was performed on both tumor and adjacent noncancerous bronchial epithelium. A general linear model tested the association between BRMS1 promoter methylation in human NSCLC and specific clinical and histopathologic variables.
Results: The BRMS1 promoter region contains a CpG island that was hypermethylated in all NSCLC cell lines and human tumors. This strongly correlated with reduced BRMS1 promoter activity. NSCLC cell lines treated with 5-azacitidine showed a robust recovery of BRMS1 mRNA and protein levels, suggesting that promoter methylation is involved in BRMS1 transcriptional regulation. Analysis of 40 patient NSCLC samples (20 adenocarcinoma and 20 squamous cell) identified a significant increase in the amount of BRMS1 promoter methylation when comparing tumor specimen to adjacent noncancerous tissue for both tumor histologies (p&lt;0.0001). Additionally, the BRMS1 promoter region was significantly more methylated in squamous cell compared to adenocarcinoma histology (p=0.01). Subsequent immunohistochemical analysis confirmed a correlation between BRMS1 promoter methylation and decreased bronchial epithelium BRMS1 protein expression (p=0.06). Moreover, in the squamous cell histology, pathologic tumor stage was associated with elevated BRMS1 methylation (p=0.04).
Conclusions: These studies identify BRMS1 promoter methylation as an important mechanism for silencing BRMS1 expression in NSCLC and highlight the potential clinical relevance of this epigenetic signature with respect to tumor histology and stage.
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 LB-278.
Abstract LB-284: Combination of antiandrogens and PI3-kinase pathway inhibitors in a model of androgen-dependent prostate cancer
Authors: Efferson Clay , Zhu Joe , Ware Chris , Tammam Jennifer , Angagaw Minilik , Reilly John F. , Sur Cyrille , Clark Edwin , Winter Chris , Zhang Weisheng , Majumder Pradip K. 
Published: February 2011

Abstract
Prostate cancer is the third most common cause of cancer-related deaths in men and is most prevalent in developed countries. The androgen signaling pathway plays a critical role in the development and maintenance of the prostate gland and is hyper-activated in prostate cancer. Additionally, gain of function mutations in the PI3 kinase pathway is associated with progression of this disease. Using the prostate-specific Pten-deleted mouse model of cancer, we show that these two pathways are distinct for tumor growth and disease progression. Depletion of androgens by either surgical or chemical castration significantly inhibits tumor growth without altering the activation of Akt and mTOR. We demonstrate that inhibition of mTOR with ridaforolimus or inhibition of Akt with MK-2206, combined with androgen deprivation (bicalutamide), results in additive anti-tumor effects in vivo when compared to single agent treatment. In this model, we also demonstrate that Akt inhibition does not block mTOR kinase activation, and that inhibiting both Akt and mTOR kinases together significantly enhances anti-tumor efficacy. Our data suggest that the combination of an anti-androgen with an mTOR inhibitor and/or Akt inhibitor may be more effective than standard therapies in treating androgen-dependent prostate cancer patients with an activated PI3 kinase 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 LB-284.
Abstract LB-286: Use of circulating tumor cells to monitor pharmacodynamic responses of patients in early-stage clinical trials
Authors: Kinders Robert J. , Wang Lihua , Kummar Shivaani , Pfister Thomas , Parchment Ralph , Tomaszewski Joseph , Doroshow James 
Published: February 2011

Abstract
Circulating tumor cells (CTCs) in peripheral blood of cancer patients potentially represent a fraction of solid tumor cells available for more frequent pharmacodynamic assessment of drug action than is possible using tumor biopsy. We have developed and validated an assay that directly examines increases in the number of cells positive for the nuclear DNA-damage marker H2AX in individual CTCs of patients treated with DNA-damaging chemotherapeutic agents. The method uses AexaFluor 488-conjugated monoclonal anti- H2AX (JBW301), to stain putative CTCs collected from blood by the CellSearch AutoPrep instrument, followed by enumeration and fluorescence analysis on the CellTracks Analyzer. Patient baselining studies demonstrated that in the absence of treatment the number of CTCs per blood aliquot is relatively constant over short time periods (2 weeks off therapy). CTC measurements are currently in use supporting four NCI new agent trials, two with cytotoxic agents and two with targeted agents (aTOP1 inhibitor and a tyrosine kinase inhibitor, TKI). CTC changes in 40 patients have been monitored on therapy to date. H2AX positive cells increased in 7/14 patients on cytotoxic therapies, 3/14 were unchanged and 4/14 were unevaluable; the fraction of H2AX positive CTCs did not decrease in any patient on cytotoxic therapy, and did not change in patients treated with TKI. The increased H2AX signal in patients on cytotoxic agents appears definitive for the cycle of therapy in which it is measured. Interestingly, 10/40 patients had increased CTC numbers immediately post-therapy, and several of these patients had few or no CTC immediately prior to therapy, suggesting that the cells were mobilized or shed from the tumor as a consequence of drug exposure. Six patients had decreases in CTC number, 12 were unchanged and 12 were unevaluable due to low CTC numbers.
These data show promise for monitoring dynamic changes in nuclear biomarkers in CTCs, in addition to a CTC count alone, to rapidly assess drug pharmacodynamic activity, in clinical trials of cytotoxic agents and targeted anti-cancer therapeutics, as well as for translational research. This method may have the potential to inform the development of new anti-cancer agents and enable longitudinal monitoring of target response.
Funded by NCI Contract No. HHSN261200800001E.
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 LB-286.
Abstract LB-289: Synthetic Hsp90 inhibitor, PF-04928473 and prodrug PF-04929113, demonstrates potent antitumor activity in head and neck cancer by inhibiting multiple proliferative and prosurvival signaling pathways
Authors: Friedman Jay , Contag Stephanie , Hu Michael , Freudlsperger Christian , Kannabiran Vishnu , Arun Pattatheyil , Mitchell James , Skillings Jamey , Kan Julie , Chen Zhong , Van Waes Carter 
Published: February 2011

Abstract
Purpose: Heat shock protein 90 (Hsp90) is a molecular chaperone that stabilizes client substrates involved in cell proliferation, survival, and apoptosis. Cancer cells display increased dependency on Hsp90 and client oncoproteins, and Hsp90 has been identified as a druggable target. This study investigated the biological activity of a synthetic small molecule inhibitor of Hsp90, PF-04928473 and the orally available pro-drug PF-04929113 in head and neck squamous cell carcinoma (HNSCC).
Experimental Design: Hsp90 expression was examined in nine human HNSCC cell lines (UMSCC). In vitro, the effect of PF-04928473 on cell proliferation, death and cell cycle were examined by MTT assay and flow cytometry. The effects on signaling molecules and cytokine production were determined using Western blot, reporter gene, and Luminex assays. In vitro combination with radiation was examined using the clonogenic survival assay. The effect of pro-drug PF-04929113 on UMSCC-11A tumor growth and Hsp90 client proteins were examined in the murine xenograft model and by immunohistochemistry (IHC).
Results: UMSCC cell lines over-expressed Hsp90 mRNA and protein when compared with normal keratinocytes. In vitro, PF-04928473 potently inhibited UMSCC cell growth, induced cell death and modulated cell cycle, with an IC50 range of 32-73nmol/L. Combining radiation and PF-04928473 increased radiation sensitivity by a dose modifying effect of 1.4. PF-04928473 significantly modulated signaling molecules, including down-regulation of c-Met receptor, IKK, IKK, and BCLXL, as well as up-regulation of cleaved PARP, pro-apoptotic p53, PUMA, and p21 protein expression. The drug inhibited AKT, ERK, and STAT3 phosphorylation, suppressed NF- B, AP-1, BCLXL, and IL8 reporter activities, and blocked IL8, IL6, and VEGF production. In vivo, pro-drug PF-04929113 20mg/kg daily for 3-7 weeks significantly inhibited tumor growth. After treatment, tumor specimens showed increased IHC staining for p53, PUMA, and TUNEL, and decreased staining for c-Met, SRC, p-STAT3, p-AKT, p-ERK, IKK, RELB, Ki67 and CD31.
Conclusion: Synthetic Hsp90 inhibitor PF-04928473 effectively modulated proliferation, cell survival, and inflammatory and angiogeneic cytokine production in HNSCC in vitro. Pro-drug PF-04929113 inhibits tumor growth in vivo by promoting apoptosis through inhibition of several key signaling pathways. [Supported by NIDCD project ZIA-DC-000073]
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 LB-289.