bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 3658: Structure-guided de novo design of selective Mcl-1 Inhibitors: Synthesis, structural and biochemical characterization
Authors: Mady Ahmed , Miao Lei , Perdih Andrej , Liao Chenzhong , Bajwa Naval , Stuckey Jeanne , Nikolovska-Coleska Zaneta 
Published: August 2015

Abstract
Myeloid cell leukemia-1 (Mcl-1) is a potent anti-apoptotic protein, member of the prosurvival Bcl-2 family. Amplification of the gene encoding the Mcl-1 protein is a common genetic aberration in human cancer. Overexpression of Mcl-1 is associated with high tumor grade, resistance to chemotherapy and poor prognosis in many types of cancers. Thus Mcl-1 is emerging as a critical survival factor in a broad range of human cancers and represents an attractive molecular target for development of a new class of cancer therapy. There is still need for developing BH3 mimetics that can efficiently and selectively target Mcl-1 protein.
Employing de-novo structure-based drug-design, we have designed a new class of potent small-molecule Mcl-1 inhibitors based on the initial lead compound discovered by high-throughput screening. Analyzing the binding model of this compound with Mcl-1 through computational docking supported by HSQC NMR studies, and using the structural information, we have designed and optimized a class of small-molecule inhibitors of Mcl-1 using a 2-(phenylsulfonamido) benzoic acid as a scaffold to reproduce the key interactions with Mcl-1 such as the conserved hydrogen bond between the aspartate in pro-apoptotic proteins and Arg263 in Mcl-1. Several co-crystal structures of this class inhibitors in complex with Mcl-1 have provided a basis for their further optimization which ultimately led to the discovery of ligands with low-nanomolar potency (Ki = 8 nM) and selectivity for Mcl-1. These compounds bind in the canonical BH3 binding groove. Interestingly, depending on the particular substitution pattern in the core scaffold, a “flip’ binding mode was observed where the substituents bind in a reverse orientation. These findings were confirmed by X-ray crystallography. The most potent compounds were further biologically characterized with a series of complementary biochemical and functional assays.
Citation Format: Ahmed Mady, Lei Miao, Andrej Perdih, Chenzhong Liao, Naval Bajwa, Jeanne Stuckey, Zaneta Nikolovska-Coleska. Structure-guided de novo design of selective Mcl-1 Inhibitors: Synthesis, structural and biochemical characterization. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3658. doi:10.1158/1538-7445.AM2015-3658
Abstract 3659: Target validation and structural optimization of selective small molecule survivin inhibitors as potential anti-cancer agents
Authors: Wang Jin , Xiao Min , Miller Duane D. , Li Wei 
Published: August 2015

Abstract
The anti-apoptotic protein survivin is highly expressed in most human cancer cells, but has very low expression in normal differentiated cells. Thus survivin is widely considered as an attractive cancer drug target. Herein we report the in vitro and in vivo study on a series of novel survivin inhibitors modified from our recently identified hit compound UC-112. NCI 60-cell line screening assay showed that three new analogs with oxyquinoline scaffold had GI50 values within the nanomolar range (513 nM, 646 nM and 891 nM). These new compounds can overcome the P-gp mediated multidrug-resistance in cancer cell lines. Western blot analyses demonstrated the high selectivity for survivin inhibition among other members in the inhibitor of apoptosis protein family. Mechanistic studies such as isothermal calorimetry measurements, survivin protein pull-down assay and fluorescence polarization assay confirm that these novel compounds indeed target survivin and inhibit its function. The most active compound showed excellent aqueous solubility of 148.7 μM (PBS pH7.4), reasonable metabolic stability (half-life) of 51 minutes as tested in human liver microsomes, and no significant inhibitions to major CYP enzymes except one of CYPs. Rat pharmacokinetic studies indicated good pharmacokinetic profiles for this novel scaffold. When tested in an A375 human melanoma xenograft model, this compound effectively suppressed tumor growth and strongly induced cancer cell apoptosis in tumor tissues. Overall, our study has demonstrated that these cell-permeable small molecular survivin inhibitors possessing a novel scaffold could be developed as potent anti-tumor therapeutic agents.
Citation Format: Jin Wang, Min Xiao, Duane D. Miller, Wei Li. Target validation and structural optimization of selective small molecule survivin inhibitors as potential anti-cancer agents. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3659. doi:10.1158/1538-7445.AM2015-3659
Abstract 3665: Reconstructing the itraconazole scaffold towards improved specificity for hedeghog signaling inhibition
Authors: DeBerardinis Albert M. , Hadden M. Kyle 
Published: August 2015

Abstract
Inappropriate regulation of the hedgehog (Hh) signaling pathway contributes to the development and progression of a number of human cancers; most notably, basal cell carcinoma (BCC) and medulloblastoma (MB). Clinical validation of small molecule mediated silencing of the Hh pathway was recently demonstrated by the FDA approval of vismodegib for the treatment of locally advanced BCC, representing a first-in-class inhibitor of the Hh signaling pathway. Vismodegib antagonizes Hh signaling by directly binding smoothened (SMO), a critical regulator of the pathway and target of numerous small molecule preclinical and clinical drug candidates. Vismodegib treatments in MB patients revealed novel SMO mutants that demonstrated resistance to vismodegib therapy, which underscores the need for continued development of novel Hh pathway inhibitors. Recently, itraconazole (ITZ) was identified as an inhibitor of Hh signaling in vitro and in vivo. Characterization indicated ITZ, a clinically used antifungal agent, maintains Hh inhibition against vismodegib-resistant SMO mutants. Ongoing structure-activity analysis for the ITZ scaffold is currently being investigated to identify analogues with improved potency and reduced non-specific toxicity. Results from these studies to identify candidates with improved pharmacological profiles and selectivity for Hh signaling modulation will be described herein.
Citation Format: Albert M. DeBerardinis, M. Kyle Hadden. Reconstructing the itraconazole scaffold towards improved specificity for hedeghog signaling inhibition. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3665. doi:10.1158/1538-7445.AM2015-3665
Abstract 368: Phage display derived antibodies for the detection of mesenchymal CTCs in TNBC
Authors: Kalscheuer Stephen , Panyam Jayanth 
Published: August 2015

Abstract
Enumeration of circulating tumor cells (CTCs) in peripheral blood of patients allows clinicians to obtain immediate evidence of metastatic dissemination. CELLSEARCH® is the only method currently approved for CTC detection (1). The critical assumption of the CELLSEARCH® platform is that CTCs will express EpCAM, based on the fact that the cell of origin in carcinoma is epithelial. However, the key cellular event that gives rise to CTCs is epithelial-to-mesenchymal transition (EMT) and the acquisition of the mesenchymal phenotype within the primary tumor. Recent studies have demonstrated EMT marker gene expression in CTCs, especially during disease progression. (2, 3). Thus, the full complement of CTCs may not be effectively captured with existing CTC technologies that rely solely on epithelial marker expression.
We have developed a competition based cell panning procedure which employs a commercially available single chain Fv (scFv) phage display library to identify antibodies with selective affinity to EMT phenotypic cells. HMLE cells as well as a sub-clone stably expressing Twist1 (HMLE-Twist1; a transcription factor known to induce EMT) were used for the panning. A two-color fluorescent scheme was employed to selectively sort the target cells from mixed populations containing the control cells, in the presence of phage library, via fluorescence activated cell sorting. Repeated iterations of this procedure yielded a scFv (‘clone 6′) with selective affinity to HMLE-Twist1cells. We then engineered a full length human IgG1 antibody in which the variable region sequences were derived from clone 6 scFv. The clone 6 IgG showed high affinity for metastatic cell lines (MDA-MB-231-LM2, LCC6, and HS578T). The antibody was also able to detect the presence of CTCs in an orthotopic MDA-MB-231-LM2 mouse tumor model. Intra-sample comparison showed distinct cell populations captured with anti-EpCAM antibody and Clone 6 IgG. Unlike those captured by anti-EpCAM antibody, the cells captured by Clone 6 were negative for EpCAM expression and were mesenchymal in phenotype. Future studies will examine the usefulness of clone 6 IgG in recognizing CTCs in patient samples.
References
1. M. Cristofanilli et al., New Engl J Med 351, 781 (2004).
2. B. Aktas et al., Breast Cancer Res : BCR 11, R46 (2009).
3. G. Kallergi et al., Breast Cancer Research : BCR 13, R59 (2011).
Citation Format: Stephen Kalscheuer, Jayanth Panyam. Phage display derived antibodies for the detection of mesenchymal CTCs in TNBC. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 368. doi:10.1158/1538-7445.AM2015-368
Abstract 3796: Synergistic effect of targeted combination therapy in bladder cancer model using HSP90 inhibitors
Authors: Chelluri Raju , Agarwal Piyush K. , Neckers Leonard M. , Smith Armine K. 
Published: August 2015

Abstract
Background
In order to survive bladder cancer (BCa) cells deregulate key pathways - including the inhibition of apoptosis - while developing “oncogene addiction” to molecular chaperones such as Heat Shock Protein 90 (HSP90). While successful in vitro, monotherapies targeting such pathways have failed in clinical trials. We aim to show the superiority of combination therapy using proteostatic and targeted cytotoxic agents. We hypothesize that these combinations will synergize to increase cytotoxicity (CT) in BCa by amplifying the apoptosis via simultaneous activation of both intrinsic and extrinsic apoptotic pathways.
Methods
The proteostatic agents tested were the HSP90 inhibitor STA9090 (9090) and the proteasome inhibitor Marizomib (NPI). The cytotoxic agent used was a synthetic TRAIL ligand. These agents were tested in multiple ATCC BCa cell lines and the NCI patient tumor-derived BCa cell line UOBL 101 (UOBL). CT was determined via MTT assay. Mechanism of cytotoxic response was investigated using a series of immunoblots targeting the components of intrinsic and extrinsic apoptotic pathways and nuclear degradation proteins. All the assays were performed in triplicates for validation.
Results
9090 (IC50 7.4-10 nM) was effective in all cell lines, as was NPI (IC50 10-20 nM). TRAIL caused 100% CT in UOBL (IC50 2.5 ng/mL, 95% CI [1.0, 7.0]) and a maximal 50% CT in T24, however the cytotoxicity of individual agents was not sustained. Combination effects of 9090 + TRAIL and NPI + TRAIL demonstrated an increase from 50% CT to 100% CT at the IC50 of both 9090 and NPI, and this effect was sustained over the course of the experiment. The increased cytotoxicity of combination therapy had corresponded to rapid cytoplasmic release of cytochrome c, additive increase in cleaved caspase 3 and caspase 8, with the corresponding increase in cleaved PARP and γ-H2ax.
Conclusions
Combination of a pro-apoptotic agent with a molecular chaperone or proteasome inhibitor holds promise in BCa therapyby affecting intracellular anti-apoptotic signaling and compromising efficient proteostasis in cancer cells lines, and should be investigated further.
Citation Format: Raju Chelluri, Piyush K. Agarwal, Leonard M. Neckers, Armine K. Smith. Synergistic effect of targeted combination therapy in bladder cancer model using HSP90 inhibitors. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3796. doi:10.1158/1538-7445.AM2015-3796
Abstract 38: ERK5 inhibitor XMD8-92 for malignant mesothelioma treatment: A preclinical study
Authors: Shukla Arti , Thompson Joyce , Shukla Anurag , Leggett Alan , MacPherson Maximilian , Beuschel Stacie 
Published: August 2015

Abstract
Malignant mesothelioma (MM) is an aggressive cancer in dire need of successful treatment. We are first to demonstrate that Extracellular signal regulated kinase 5 (ERK5) plays an important role in MM pathogenesis (Clinical Cancer Research, 19, 2013). In this study we used genetically manipulated (ERK5 inhibited) MM cell lines to show that MM tumorigenesis is influenced by ERK5. In the present study we used recently discovered specific ERK5 inhibitor (XMD8-92) to show that it regulates MM tumor growth both in vitro and in vivo. First, we show that XMD8-92 inhibits ERK5 phosphorylation in 3 out of 4 MM cell lines showing constitutive activation of ERK5. Next, time and dose dependent study demonstrated significant cytotoxicity of XMD8-92 on 3 different MM cell lines. We also showed that soft agar colony forming efficiency of H2373 MM cells was significantly reduced in response to XMD8-92 treatment. Furthermore, in vivo studies using syngeneic mouse model of intraperitoneal mesothelioma showed that XMD8-92 treatment (50 mg/kg, ip, 1x daily for 3 weeks) resulted in significant decreases in tumor weights as compared to vehicle treated mice. Total and differential cell counts in peritoneal lavage fluid (PLF) were also inhibited by XMD8-92 suggesting the role of inflammation in MM tumor growth and their inhibition by ERK5 inhibitor. Cytokine profile assessment in PLF demonstrated the reduced levels of VEGF and IL-6 in XMD8-92 treated animals as compared to control animals receiving saline. FGF2, MCP-1, G-CSF, KC and RAGE levels were, however, not significantly impacted by the ERK5 inhibition. Taken together these data suggest that ERK5 inhibitor/ERK5 inhibition could be used for inhibiting the growth of MM tumors. Currently we are exploring the role of XMD8-92 alone as well as in combination with chemotherapeutic drugs for the treatment of MM using various mouse models. We are also exploring the role(s) of ERK5 inhibitor in inflammasome regulation by chemotherapeutics. This work is supported by NIEHS RO1 ES021110 and VCC/LCCRO grants.
Citation Format: Arti Shukla, Joyce Thompson, Anurag Shukla, Alan Leggett, Maximilian MacPherson, Stacie Beuschel. ERK5 inhibitor XMD8-92 for malignant mesothelioma treatment: A preclinical study. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 38. doi:10.1158/1538-7445.AM2015-38
Abstract 3800: Targeting PI3K signaling pathway for therapeutic enhancement of verteporfin-mediated photodynamic therapy
Authors: Kraus Daniel E. , Palasuberniam Pratheeba , Chen Bin 
Published: August 2015

Abstract
Photodynamic therapy (PDT) induces cell injury and death through generation of reactive oxygen species (ROS) after light activation. Verteporfin is a photosensitizer that has been approved for the treatment of age-related macular degeneration and is under investigation for targeting tumor vasculature for therapy. Being primarily localized in mitochondria, verteporfin-mediated PDT induced a rapid apoptotic cell death in SVEC mouse endothelial cells by activating mitochondria-initiated cell death pathways. However, activation of phosphatidylinositol 3-kinase (PI3K) signaling pathway was also observed after verteporfin-PDT, especially at a sub-lethal dose. Furthermore, activation of PI3K signaling was correlated with cell growth after PDT. Thus, the goal of this study is to test the hypothesis that therapeutic outcome of verteporfin-PDT can be enhanced by targeting PDT-induced pro-survival PI3K signaling pathway.
We found that PI3K-mTOR pathway inhibitor NVP-BEZ235 (BEZ235) significantly inhibited PDT-induced PI3K signaling activation and combination of BEZ235 and verteporfin-PDT resulted in more cell apoptosis and greater inhibition in cell proliferation in SVEC cells. The combination therapy led to significantly more tumor growth inhibition than each individual treatment in the PC-3 prostate tumor model. Examination of tumor samples for PI3K signaling activity and functional vasculature revealed that the combination treatment caused more inhibition in PI3K signaling and reduction in functional blood vessels than verteporfin-PDT or BEZ235 treatment alone. These results indicate that targeting pro-survival PI3K signaling pathway is an effective approach for enhancing tumor response to verteporfin-PDT.
Citation Format: Daniel E. Kraus, Pratheeba Palasuberniam, Bin Chen. Targeting PI3K signaling pathway for therapeutic enhancement of verteporfin-mediated photodynamic therapy. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3800. doi:10.1158/1538-7445.AM2015-3800
Abstract 3827: Histone methytransferase SMYD3 promotes invasion in ovarian carcinoma spheroids
Authors: Lyu Tianjiao , Jia Nan , Wang Jieyu , Bast Robert C. , Baak Jan Pa , Hua Keqin , Feng Weiwei 
Published: August 2015

Abstract
Epithelial ovarian cancer (EOC) metastasis is a direct contributor to high recurrence and low survival for patients with this disease. The ovarian carcinoma spheroids are cells shed from primary tumors and aggregate in ascites, bearing the main responsibility for metastasis. “Epigenetic plasticity” refers to the capability of mammalian cells to alter their differentiation status via chromatin remodeling-associated alterations in gene expression. In the current study, we extend this attribute of epigenetic plasticity to aggressive ovarian cancer cells. Upon a simple alteration in the microenvironment, transition from two- to three-dimensional culture, we mimicked the in-vivo spheroids formation and found that a batch of histone markers and their enzymes experienced a marvelous elevation, among which, H3K4Me3 and its methyltransferase SMYD3 emerged as focal points for their concordant change. Using siRNA-SMYD3-depletion, we proved SMYD3 was attributed to the enhanced invasion and adhesion abilities in spheroids compared to monolayer cells. Gene array results further discovered that integrin-related molecules were suppressed after SMYD3 depletion. By ChIP assay, we confirmed SMYD3 and H3K4me3 binding increased at ITGA8, ITGB6 and ITGAM's promoter, indicating that SMYD3 regulated those downstream genes through methylating H3K4. At last, we reconfirmed the SMYD3 and integrin-mediated adhesion molecules were both activated in in vitro model, in vivo intraperitoneal xenograft model and EOC patients’ spheroids. Overall, our results indicated that ovarian cancer cell epigenetic plasticity reflects an inherent transcriptional flexibility for context-responsive alterations in phenotype and SMYD3 could be a promising epigenetic marker for anti-tumor treatment.
Citation Format: Tianjiao Lyu, Nan Jia, Jieyu Wang, Robert C. Bast, Jan Pa Baak, Keqin Hua, Weiwei Feng. Histone methytransferase SMYD3 promotes invasion in ovarian carcinoma spheroids. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3827. doi:10.1158/1538-7445.AM2015-3827
Abstract 3853: Unique pattern of copy number changes including chromothripsis in pulmonary adenocarcinoma with EML4-ALK fusion
Authors: Ninomiya Hironori , Kato Motohiro , Ogawa Seishi , Motoi Noriko , Takeuchi Kengo , Kodama Tatsushi , Sakamoto Hiroshi , Ishii Nobuya , Fujiwara Mutsunori , Ishikawa Yuichi 
Published: August 2015

Abstract
Background: A subset of lung adenocarcinomas harbors an ALK fusion gene resulting in dominant oncogenic activity. Gene inversion may play a main role in forming the fusion, not producing copy number changes. But its detailed mechanism leading to gene fusion remains unsolved.
MATERIAL AND METHODS: To elucidate the underlying mechanisms resulting in gene fusion, two cancer cell lines positive for EML4-ALK fusion and surgically resected frozen specimens (33 ALK fusion-positive and 95 ALK fusion-negative adenocarcinomas) were analyzed using Affymetrix CytoScan HD Array with Chromosome Analysis Suite (ChAS) software for cell lines (JFCR-LC649 and JFCR-LC654) and Affymetrix GeneChip Mapping 250K arrays for surgical specimens.
RESULTS: One (JFCR-LC649) of the two cell lines with gene fusion showed an extremely frequent change of copy number, or “copy number oscillation”, which we thought was chromothripsis. In surgical materials, 30% (10/33) of adenocarcinomas with ALK fusion harbored frequent copy number changes at various degrees, but not like the “oscillation” pattern. None of the 95 resected cases without ALK fusion showed similar genomic aberrations. These results from the JFCR-LC649 line and the 10 surgical cases indicated that genomic changes resulting in copy number alterations (including chromothripsis) as well as a simple inversion may cause gene fusion.
CONCLUSION: As well as genome inversion, copy number alterations such as chromothripsis contribute to gene rearrangements resulting in the EML4-ALK fusion.
Citation Format: Hironori Ninomiya, Motohiro Kato, Seishi Ogawa, Noriko Motoi, Kengo Takeuchi, Tatsushi Kodama, Hiroshi Sakamoto, Nobuya Ishii, Mutsunori Fujiwara, Yuichi Ishikawa. Unique pattern of copy number changes including chromothripsis in pulmonary adenocarcinoma with EML4-ALK fusion. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3853. doi:10.1158/1538-7445.AM2015-3853