bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract C93: The design and synthesis of a novel fluorogenic probe targeting inactive forms of Burton's tyrosine kinase for high-throughput binding assay.
Authors: Kawahata Wataru , Asami Tokiko , Sawa Masaaki 
Published: June 2012

Abstract
The aberrant activation of B-cell receptor (BCR) signaling is thought to promote cancer cell expansion and survival in B cell lymphoma and chronic lymphocytic leukemia. The Burton's tyrosine kinase (Btk) is a member of the Tec family of cytoplasmic tyrosine kinase and plays a crucial role in the BCR signaling which is essential for B-cell development and activation. Therefore inhibitors of Btk are considered as potential therapeutic agents for the treatment of B cell lymphoma, chronic lymphocytic leukemia and autoimmune diseases. Targeting inactive conformations of kinase is an attractive approach for drug discovery to develop a selective kinase inhibitor, because it is believed that structures of inactive conformation are much diverse than that of the active kinase form. To identify compounds that preferentially bind to the inactive conformation of Btk, we have designed and synthesized a novel fluorogenic probe for high throughput screening.
Methods: CGI1746 has been reported to bind to the inactive form of Btk, so we chose this compound to probe the inactive conformer of Btk. To detect its binding to the active site of Btk, we covalently attached an environmentally-sensitive fluorophore, nitrobenzoxadiazole (NBD) to CGI1746 via various linkers. The fluorescence of NBD is extremely sensitive to the local environment around the chromophore. Namely, NDB is almost nonfluorescent in aqueous solution, but become highly fluorescent in nonpolar solvents or when bound to proteins. Therefore we expected that this unique environment-sensitive fluorescent property would make the experiment process simple, easy handling, and of course, does not require radioisotope labeling.
Results: We synthesized NBD-labeled CGI1746 derivatives with different likers, and tested their inhibitory activity against Btk. Most of the compounds syntheszed were found to be execellent inhibitors of Btk with an IC50 value in the low nanomolar concentration range. As expected, the NBD-labeled CGI1746 probe showed strong fluorescence when it mixied with Btk protein but quenched by adding of free CGI1746. Interestingly, the fluorescence intensity of the probes varied considerably along with the linker structures. To validate if the probes can detect compounds that bind preferenctially to inactive form of Btk, we screened the small compound library using activated Btk and unactivated Btk. Detailed data of screening will be presented in this poster.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C93.
Abstract C97: Studies on the signaling pathway for cancer cell migration based on chemical genomic approach.
Authors: Magi Shigeyuki , Tashiro Etsu , Imoto Masaya 
Published: June 2012

Abstract
Cell migration is known to be related to not only physiological phenomena such as embryonic development, immune reaction, and wound healing, but also pathological phenomena such as asthma, vascular disease, and cancer metastasis. However, because genetic mutations of each cancer cell causing high migration ability depend on cell types, it still remains unclear that which pathways are the unity of cancer cell migration signaling irrespective of cancer cell types, and which pathways are the diversity depend on cell types. The aim of this study is to reveal the diversity and unity of regulatory signaling for cancer cell migration based on chemical genomic approach.
To understand the diversity and unity of regulatory signaling for cancer cell migration, the effects of 38 small compounds, whose target protein are already identified, on cell migration ability of 10 types of cancer cells were assessed quantitatively by wound healing assay. Two-way hierarchical clustering was done on migration ability profile by small compounds or cancer cell types. As a result, cancer cells tested in this study were classified into three clusters (group A∼C). Interestingly, epidermoid carcinoma A431 cells and esophageal squamous carcinoma EC109 cells (group B) were classified different cluster from esophageal squamous carcinoma TE8 cells and thyroid medullary carcinoma T.T cells (group C), whereas all four cell lines were induced migration by EGF stimulation. On the other hand, compounds were clustered into five clusters (cluster I∼V). The compounds classified into cluster I (e.g., V-ATPase inhibitor and bisphosphonates) showed little inhibitory effect on all types of cell migration. The compounds clustered into cluster II (e.g., EGFR inhibitor and ROCK inhibitor) showed stronger inhibitory effect on the migration of group B and C than A. The compounds classified into cluster III (e.g., JNK inhibitor) showed strong inhibitory effect on all types of cell migration tested in this study. The compounds clustered into cluster IV (e.g., PI3K inhibitors and mTOR inhibitor) showed stronger inhibitory effect on the migration of group B than C. On the contrary, the compounds classified into cluster V (e.g., MEK inhibitor and p38 inhibitors) showed stronger inhibitory effect on group C than B. These results indicate that JNK play the common role in cancer cell migration, and belonging to cluster II, IV, and V would have different function in each type of cancer cell migration. We are now investigating how these molecules actually operate in the signaling pathway in each cancer cell, and trying network analysis by the combination of chemical biology and systems biology.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C97.
Abstract CN05-04: Opportunities for targeting homologous recombination in human cancers.
Authors: Powell Simon N. 
Published: June 2012

Abstract
BRCA2 mediates homologous recombination (HR) via its direct interaction with Rad51. There is ample genetic and biological evidence that BRCA1 and BRCA2 are functioning in the same pathway of DNA repair, but the functional connection between the two proteins is poorly understood. Interestingly, a mutation of BRCA1 (S988A) localized normally to ionizing radiation induced nuclear foci (IRIF), but the BRCA2 protein could not be recruited to BRCA1 at the damage site. Phosphorylation of BRCA1 at the S988 site is carried out by Chk2, which was also required for BRCA2 to localize to sites of DNA damage and support homologous recombination. These observations suggest that CHK2-BRCA1-BRCA2-Rad51 function in a single pathway of homologous recombinational repair to prevent the development of breast cancer. Loss of function of BRCA1/BRCA2 is a tumor-specific finding, making the role of alternative repair pathways in these cells critical for their survival. We show that loss of Rad52 function is synthetic lethal with BRCA1, PALB2 or BRCA2 deficiency, whereas there is no impact on cell growth in wild-type cells. The frequency of both spontaneous and double-strand break-induced homologous recombination, plus ionizing radiation induced Rad51 foci, decreased when Rad52 was depleted in BRCA2-deficient cells, with no effect in BRCA2-complemented cells. The observation that Rad52-inactivation is synthetic lethal with BRCA2 makes Rad52 a target for therapy in these tumors. The BRCA1-BRCA2 pathway can be functionally inactivated in sporadic breast cancer, perhaps as frequently as 20% of cases, suggesting that the pool of patients with defects in homologous recombinational repair is larger than initially expected. The functional assessment of defects in homologous recombination was assessed by ionizing-radiation (ex-vivo exposure) induced Rad51 foci and confirmed by characteristic patterns of array comparative genomic hybridization. The inactivation of the BRCA1-BRCA2 pathway allows the use of specific therapies designed to exploit the defects in DNA repair.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr CN05-04.
Abstract KN01: Overcoming barriers to new drug development.
Authors: Hait William N. 
Published: June 2012

Abstract
The forty years that followed the signing of the National Cancer Act witnessed substantial progress in our understanding of the biology of human cancer. This knowledge has translated into several important advances for the treatment of patients with both hematological and solid tumor malignancies. Yet, during the last 15 years we have not seen a proportional increase in the approval rate of new drugs. The drop-off in efficiency of drug development coincided, unexpectedly, with the adoption of target-based screening, which replaced a physiological or phenotypic approach. The power of molecular biology enticed drug developers to believe that the ability to express a cloned gene product to high purity and the utility of structural biological approaches to rational drug design, led to remarkably potent and selective inhibitors. Unfortunately, the understanding of how the target was wired into a specific tumor type was less obvious, making even optimal target engagement in the clinic insufficient to produce striking benefits to patients. The phenotypic approach is agnostic to target but instead relies on a readout that predicts efficacy in the clinic. For both the target-based and for the phenotypic approaches, the rate limiting step in cancer drug discovery is a predictive pre-clinical model of a specific tumor type. The challenges that remain and the advances we have made in translational research is the subject of this presentation.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr KN01.
Abstract PL02-01: Changing cell fate in cancer: Lessons from melanoma.
Authors: Zon Leonard I. 
Published: June 2012

Abstract
Melanoma is a devastating disease with great morbidity and mortality. We are using the zebrafish as a model to study melanoma, making use of its excellent genetics, development, and large numbers of adults with cancer. A human constitutively active BRAF was fused to the melanocyte specific MITF promoter. This was injected into zebrafish embryos, generating transgenic zebrafish. These fish were crossed to a P53 mutant line generating a melanoma model. Microarray analysis of this melanoma demonstrates similarities to gene expression signatures in human melanoma. Mating the BRAF P53 fish to an MITF mutant led to complete abrogation of melanoma. The lack of melanocyte progenitors due to MITF deficiency led to an absence of tumor formation. A vector called Mini Cooper was generated in which an MITF minigene could rescue melanocyte formation in the BRAF P53 MITF mutants and a gene of interest could be probed for enhanced or expressed tumor formation. Screening an interval of human chromosome 1 (54 independent genes). That is amplified in 30% of patients) in the minicooper plasmid injection found SETDB1 a histone methyltransferase that is thought to suppress gene expression. ChIPSeq analysis in human melanoma samples demonstrated that SETDB1 binds to genes such as the Hox locus and alters their expression. SETDB1 is a potential target for anti-melanoma therapy. In another screen, small molecules were added to zebrafish embryos in an effort to abrogate neural crest development. One small molecule was found to inhibit an enzyme (DHODH), and an arthritis drug (leflunomide) that also inhibits DHODH was found to similarly block neural crest development. This DHODH inhibitor (leflunomide) worked synergistically in xenograft studies to block melanoma formation. This combination therapy will enter into the clinic as a trial for patients with metastatic melanoma. Using genetics, it was found that the DHODH inhibitor which blocks uridine production has an effect on transcription elongation and the targets of this include genes that are activated by MYC and by MITF. The zebrafish has led to the discovery of two new targets for melanoma therapy, and one of those is proceeding to the clinic.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr PL02-01.
Abstract PR-8: Development of a multiplex panel of putative biomarkers for assessing pharmacodynamic effects of anticancer therapies targeting apoptosis.
Authors: Srivastava Apurva K 
Published: June 2012

Abstract
Background: Regulators of apoptotic cell death are high interest targets for cancer therapy, and several mechanism-based investigational agents in clinical development directly target the molecular components of apoptosis pathways. We have undertaken development of a multiplex assay of candidate biomarkers of this mechanism for quantifying the commitment, onset, and induction of apoptosis by both intrinsic and extrinsic pathways. Quantitation of these pharmacodynamic biomarkers in early clinical trials will assist hypothesis testing and confirm the intended mechanism of action of investigational agents. The panel may also be adaptable to diagnostic applications to identify patients most likely to respond to a particular apoptosis inducer.
Methods: The panel being developed includes quantitative determinations of Bcl-xl, Mcl-1, Survivin, Smac dimer, cleaved Lamin-B, active/total Caspase-3, BIM, and six oligomeric forms of Bax and Bak with Bcl2 family proteins in lysates of tumor biopsies. Calibrators for oligomeric proteins, which are formed in vivo by the non-covalent association of BH3 domain proteins, are being developed as recombinant fusion proteins. The housekeeping gene GAPDH is used as an internal control. The multiplex, sandwich immunoassay is built on the Luminex® xMAP technology platform using MagPlex bead, which allows for significant automation in the detection of multiple proteins in a 96-well plate format, with increased sensitivity, smaller sample volumes, and less preparation time.
Results: Suitable, high quality capture antibodies against proteins in the panel as well as detection antibodies labeled with fluorescent dyes have been identified and tested for sandwich formation using recombinant calibrators and cell lysates. Capture and reporter antibody pairings are currently standardized for optimal assay performance. The feasibility of developing several oligomeric calibrators (among Bak-Bcl-xl, Bak-Mcl-1, Bak-Bak, Bak-Bax, Bax-Bax, and Bax-Bcl2) as recombinant fusion proteins has been established.
Conclusions: The proposed multiplex panel represents the most comprehensive selection of putative biomarkers for the apoptosis pathway, to date. Our strategy to quantify oligomeric forms of Bcl-2 family proteins in tumor lysates represents a novel approach since it evaluates a pathway based on alterations in protein dynamics, instead of the levels of various proteins. Once developed, validated, and fit to purpose, the panel will facilitate drug discovery and the real-time pre-clinical and clinical evaluation of drugs targeting apoptosis.
Funded by NCI Contract No HHSN261200800001E.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr PR-8.
Abstract 1005: Plk3 functions as an essential component of the survival and hypoxia regulatory pathway by direct phosphorylation and regulation of PTEN and HIF-1α
Authors: Yao Yixin , Xu Dazhong , Costa Max , Dai Wei , Lu Luo 
Published: June 2012

Abstract
Plk3, a member of the Polo-like kinase family, plays an important role in regulating cell cycle progression and cell cycle checkpoints in response to genotoxic stresses. Plk3 is also strongly implicated in tumorigenesis because PLK3-/- mice develop tumors in multiple organs at an enhanced rate. We have previously shown that many of the tumors developed in the PLK3 null mice are large in size and are highly vascularized, suggesting that this kinase may be involved in regulating the angiogenesis pathway. By studying PLK3 null primary isogenic murine embryonic fibroblasts (MEFs), we tested the hypothesis that Plk3 functions as a component in the hypoxia signaling pathway. PLK3-/- MEFs contained a reduced level and activity of PTEN that closely correlated with increased PDK1 and Akt1 activation as well as decreased GSK3β activity. The activated Akt1 in PLK3 null MEFs was closely associated with enhanced stability of HIF-1α under hypoxic conditions. Purified recombinant Plk3 phosphorylated PTEN and HIF-1α in vitro and phospho-mutant analysis indicated that Plk3 directly regulates these proteins in vivo. Combined, our study identifies Plk3 as a new and essential player in the regulation of the hypoxia and angiogenesis signaling pathway.
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 1005. doi:10.1158/1538-7445.AM2011-1005
Abstract 1011: NNK promotes migration and invasion of cancer cells through activation of c-Src, PKCι and FAK loop
Authors: Shen Jie , Xu Lijun , Sun Shi-Yong , Khuri Fadlo , Deng Xingming 
Published: June 2012

Abstract
Cigarette smoking, either active or passive, is the most important risk factor in the development of human lung cancer. Mounting evidence indicates that cigarette smoke constituents not only contribute to tumorigenesis but also may increase the spread of cancer in the body. Nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) is formed by nitrosation of nicotine and has been identified as the most potent carcinogen. NNK, an important component in cigarette smoke, may also promote tumor metastasis by regulating cell motility. Here we found that NNK can induce activation of a functionally interdependent protein kinase cascade, including c-Src, PKCι and FAK, in association with increased migration and invasion of human lung cancer cells. c-Src, PKCι and FAK are extensively co-localized in the cytoplasm. Treatment of cells with α7 nAChR specific inhibitor α-bungarotoxin (α-BTX) blocks NNK-stimulated activation of c-Src, PKCι and FAK and suppresses cell migration and invasion. Intriguingly, NNK enhances c-Src/PKCι and PKCι/FAK bindings, indicating a potential mechanism by which these kinases activate each other. Specific disruption of c-Src, PKCι or FAK expression by RNA interference significantly reduces NNK-induced cell migration and invasion. These findings suggest that NNK-induced migration and invasion may occur in a mechanism through activation of a c-Src/PKCι/ FAK loop, which can contribute to metastasis and/or development of human lung 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 1011. doi:10.1158/1538-7445.AM2011-1011
Abstract 1015: P38 mitogen-activated protein kinase signaling and viability of lung cancer cells from never or light smoker patients
Authors: Planchard David , Soria Jean-Charles , Dorvault Nicolas , Camara-Clayette Valérie , Fouret Pierre 
Published: June 2012

Abstract
Purpose: Expression levels of DNA repair proteins and activated mitogen-activated protein kinases (MAPKs) may differ according to smoking status. We investigated whether P38 MAPK activity contributed to the viability and sensitivity to cisplatin of lung cancer cells lines from never or light smokers and to ERCC1 mRNA expression.
Methods: Activated P38 MAPK was tested by means of immunohistochemistry as a predictor of ERCC1 levels in 117 lung adenocarcinomas. Cell viability of NCI-H1975, NCI-H1793, NCI-H1650 and NCI-H1651 was measured after treatment with the P38 MAPK inhibitor SB202190 and cisplatin. The role of P38α (MAPK14), P38β (MAPK11) isoforms and ERCC1 was evaluated using ARN interference. ERCC1 mRNA was measured by quantitative PCR.
Results: ERCC1 protein expression was predicted by activated P38 MAPK in lung adenocarcinoma tissues. The P38 specific inhibitor SB202190 induced a strong decrease (P&lt;0.01) in cell viability of NCI-H1975 (43%) and NCI-H1650 (63%) compared to control. When SB202190 was combined with cisplatin, cell viability decreased (P&lt;0.01) in every cell line including cisplatin resistant NCI-H1793. The combination of drugs reduced cell viability more than cisplatin (P&lt;0.01) for NCI-H1793, NCI-H1650 and NCI-H1651, and it was synergistic for NCI-H1793 and NCI-H1651. Genetic inhibition targeting both MAPK11 and MAPK14 reduced the viability of every cell line (P&lt;0.01) with a dose-response for three of them. The decrease in cell viability with genetic inhibition at 25 nM was higher (P&lt;0.01) than with cisplatin for NCI-H1793 (67% vs. 35%) and NCI-H1650 (55% vs. 38%). In separate experiments, MAPK11 downregulation reduced viability of every cell line (P&lt;0.01), while MAPK14 downregulation reduced viability of NCI-H1651. The effect of cisplatin was higher after MAPK11 downregulation for NCI-H1651 and after MAPK14 downregulation for NCI-H1650. In addition, both SB202190 and MAPK11 inhibition reduced excision repair cross-complementing 1 mRNA levels.
Conclusion: lung cancer cells from never or light smokers rely on P38 MAPK signaling for their survival whether or not they harbor EGFR mutations. MAPK11 is involved in that pathway and might contribute to ERCC1 expression. Sensitization to cisplatin can be achieved by pharmacological inhibition of P38 MAPK signaling in some lung cancer models from never smokers.
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 1015. doi:10.1158/1538-7445.AM2011-1015