bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 4021: Donor-specific primary monocyte-derived dendritic cell maturation model for high-throughput screening of immunostimulatory adjuvants
Authors: Chen Qin , Lawrenz Anthony , Wang Alan , Kelly Erin , Harberts Erin , Ernst Robert K. , Tong Jay 
Published: July 2017

Abstract
Dendritic cell (DC) based immunotherapy is a promising treatment alternative for various solid tumor and hematological malignancies. DCs are capable of initiating and propagating antigen-specific adaptive immune responses through their intrinsic maturation process. Identifying novel, effective adjuvant drug candidates that can stimulate DC maturation while understanding and accounting for the variability of patient-specific DC cell responses to the immunostimulatory adjuvants is essential for development of such immunotherapies. Reliable, high throughput assay platforms that characterize patient-specific modulatory effects during the DC maturation process in vivo and in vitro are also highly desirable. In this study, we present a high throughput in vitro primary cell assay to evaluate dose-dependent DC maturation in a panel of human leukocyte antigen (HLA) typed individual donors. CD14+ monocytes from four healthy donors were isolated from leukapheresis derived peripheral blood mononuclear cells (PBMC) and cultured for seven days with GM-CSF and IL-4 to achieve differentiation to DC. Cells were then stimulated for 24 hours with lipopolysaccharide (LPS), CpG oligonucleotides, or nine different novel toll-like receptor 4 (TLR4) ligands at three concentrations. To quantify the differentiation of monocytes into DC and subsequent maturation, flow cytometry was used to measure the expression of biomarkers, MHC-II, CD40, CD80, CD83, and CD86. Greater than 99% MHC-II expression was observed across all donors and confirmed successful differentiation to DC. The TLR4 ligands showed reduced biomarker expression, as compared to pathogenic E. coli LPS but similar to PHAD, a synthetic TLR4 agonist currently used in adjuvants. While monocytes from all donors responded to the ligands tested, the intensity of activation marker expression varied among donors with LPS/TLR4 ligand induced maturation process showing 43-91% CD40 and 27-82% CD83 expression, highlighting the necessity of multi-donor screening for drug development. In conclusion, a high throughput in vitro primary monocyte derived DC differentiation assay has been developed and is commercially available to assist researchers in characterizing donor-specific DC responses to immunostimulatory adjuvants.
Citation Format: Qin Chen, Anthony Lawrenz, Alan Wang, Erin Kelly, Erin Harberts, Robert K. Ernst, Jay Tong. Donor-specific primary monocyte-derived dendritic cell maturation model for high-throughput screening of immunostimulatory adjuvants [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4021. doi:10.1158/1538-7445.AM2017-4021
Abstract 4024: Physiologically relevant target engagement using the cellular thermal shift assay (CETSA)
Authors: Karen Jakob , Sioberg Catrine , Shalaly Nancy Dekki , Molina Daniel Martinez 
Published: July 2017

Abstract
Targeted therapies are dependent on adequate occupancy and target engagement to reach their efficacy measure. Yet, more than half of novel candidate drugs entering clinical trial stage fail before proof of concept is achieved. Inadequate target engagement is often at the root cause of these failures. Therefore, we have developed a versatile label-free method to quantify the target engagement of drugs on their native physiological relevant targets. The method is validated in multiple sample matrices, using different technical platforms to allow studies of target engagement from bench to bedside: in living cells and tissue from rodents and man.
CETSA(®) is a patented biophysical method measuring the thermal stability of drug target proteins and the shift induced by their ligands. By quantifying the melting temperature and shift induced by the ligand we can quantify the potency of target engagement. This potency determination allows filtering of candidate drugs by their ability to engage the target in its physiologically relevant form, in relevant sample formats such as intact cells or tissue.
We present several applications of the method and the utility in preclinical in vitro studies and translation to in vivo systems. In addition, new powerful detection formats are being evaluated and will be presented.
The utility and value of the CETSA(®) method enabling preclinical development of novel drugs is substantiated by the examples included here. We show the value of the method both for compound/drug profiling, for target profiling and for unbiased drug profiling on whole proteomes in response to drug treatments.
Such datasets can be generated from in vitro systems to clinical samples and may reduce the high attrition rate in proof of concept studies by facilitating the discovery, development and evaluation of novel drugs.
Citation Format: Jakob Karen, Catrine Sioberg, Nancy Dekki Shalaly, Daniel Martinez Molina. Physiologically relevant target engagement using the cellular thermal shift assay (CETSA) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4024. doi:10.1158/1538-7445.AM2017-4024
Abstract 4025: Accelerating drug repurposing for cancer therapy using multiplexed viability assays
Authors: Corsello Steven M. , Mader Christopher C. , Bryan Jordan , Roth Jennifer , Peck David , Davis John , Bender Samantha , Wang Li , Wang Alice , Bittker Joshua , Vazquez Francisca , Subramanian Aravind , Tsherniak Aviad , Golub Todd R. 
Published: July 2017

Abstract
New therapies are desperately needed for patients with advanced cancer, but making safe and efficacious drugs remains expensive and time consuming. Meanwhile, multiple non-oncology drugs have been successfully repurposed for cancer, including thalidomide for multiple myeloma and aspirin for prevention of colorectal cancer. While the benefits of repurposing are clear, successes to date have been largely serendipitous. We have created two foundational tools to identify drug repurposing opportunities at a much greater scale: a new world-class screening library of more than 4,000 drugs/clinical candidates and a multiplexed method to rapidly conduct cellular viability assays across hundreds of cell lines.
PRISM, a recently developed high-throughput assay, employs DNA-barcoded cell lines to enable rapid testing of many drugs against pools of cancer cell lines. We have tested 4,100 compounds against 578 genomically characterized cancer cell lines using PRISM. Our experiment is among the largest cell line screens ever undertaken. Global analysis has revealed multiple strong clusters of active drugs, including vitamin D agonists, bromodomain inhibitors, and statins. In addition, many novel and established drug-biomarker relationships were identified, including alkylating agent response and low MGMT expression, BRAF inhibitor response and BRAF mutation, and MDM2 inhibitor response and TP53 wild-type status. Surprisingly, more than 100 non-oncology drugs unexpectedly killed multiple cancer cell lines, making them attractive repurposing candidates. For example, the FDA-approved phosphodiesterase inhibitor anagrelide selectively kills PDE3A-high lung cancer and melanoma cell lines. Confirmatory experiments are underway to validate screening results, evaluate putative biomarkers, and test drug activity in preclinical models. Importantly, this approach is expected to enable rapid initiation of clinical trials, dramatically accelerating patient access to potential new therapies.
Citation Format: Steven M. Corsello, Christopher C. Mader, Jordan Bryan, Jennifer Roth, David Peck, John Davis, Samantha Bender, Li Wang, Alice Wang, Joshua Bittker, Francisca Vazquez, Aravind Subramanian, Aviad Tsherniak, Todd R. Golub. Accelerating drug repurposing for cancer therapy using multiplexed viability assays [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4025. doi:10.1158/1538-7445.AM2017-4025
Abstract 4029: Robust Ras inhibition assay utilizing fully synthetic Ras-binding domain
Authors: Khavrutskii Lyuba , Tarasov Sergey G. , Fields Colin , Stefanisko Karen , Tarasova Nadya 
Published: July 2017

Abstract
Intensifying efforts to develop clinically useful inhibitors of Ras proteins resulted in increasing need for quantitative, reliable and robust in vitro assays of Ras activity. The vast majority of detection methods used in the assays require fusion, chemical modification or immobilization of the protein. We have found that K-Ras modifications have significant impact on its activity and function because of the highly allosteric nature of the protein. We have attached three different fluorescent moieties to two sites distant from the active site of the protein in a site-selective manner. All six modifications resulted in significant drops in affinity towards Ras-binding domain of one of Ras's major effectors c-Raf as determined by Microscale Thermophoresis (MST). Fluorescent labeling of recombinant Raf1 RBD also resulted in inhibition of K-Ras binding. To produce a pair that interacted as unlabeled proteins, we have generated RBD with a single-site attached fluorescent moiety utilizing microwave-assisted high efficiency solid phase peptide synthesis. Optimization of coupling and deprotection protocols and the type of the solid support allowed conducting the synthesis of 76 residues long protein in fully-automated manner in one run. Refolding of the product yielded RBD that was indistinguishable from the recombinant one in CD spectra, melting temperature and K-Ras binding affinity as determined by isothermal calorimetry and microscale thermophoresis. Fluorescent RBD produced significant changes in both thermophoretic signal and fluorescence anisotropy upon binding to K-Ras. Both MST and fluorescence polarization assays have proven sensitive, reproducible and straightforward for determination of Ras inhibition constant for Ras inhibitors identified by virtual screens and rational design. They can be easily adapted to high throughput screening formats. Developed synthetic protocols allow for straightforward generation of proteins with various natural and non-natural modifications.
Citation Format: Lyuba Khavrutskii, Sergey G. Tarasov, Colin Fields, Karen Stefanisko, Nadya Tarasova. Robust Ras inhibition assay utilizing fully synthetic Ras-binding domain [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4029. doi:10.1158/1538-7445.AM2017-4029
Abstract 4032: Synergistic effects of Bortezomib and JQ1 for human and canine osteosarcoma treatments
Authors: Yang Ya-Ting , Yuzbasiyan-Gurkan Vilma 
Published: July 2017

Abstract
Osteosarcoma (OS) is the most common primary malignant bone tumor of both humans and dogs, with the incidence in dogs being nearly 15 times that observed in humans. Despite advances in treatment of other cancers, the clinical outcome of OS remains poor for the past several decades. Therefore, identifying novel and effective treatments for osteosarcoma is an urgent need. Among the small molecular compounds we tested in a drug screening study, we identified a bromodomain inhibitor (JQ1) that targets bromodomains which modify chromatin and block transcription of key factors, and a proteasome inhibitor that induces cell death through various mechanisms (bortezomib) as having good growth inhibition effects on three canine OS cell lines (D17, Abrams, and Gracie) and two human OS cell lines (SAOS2 and U2OS). We then determined the IC50 values of these two drugs, the concentration capable of inhibiting proliferation by 50%. The IC50 values of bortezomib and JQ1 are both within achievable plasma concentrations and tolerable levels. JQ1 inhibited OS cell proliferation and survival by inducing G2 cell cycle arrest, while bortezomib induced G1 cell cycle arrest. In addition, these two drugs decreased cell migration ability in wound healing assay as well as invasion ability in a Matrigel assay. Furthermore, in combination studies using both JQ1 and bortezomib, we identified synergistic effects. With these promising results from in vitro studies, we further examined JQ1 as therapeutic agent in an orthotopic tumor xenograft mouse model. Using OS cells stably transfected with a lucerifase vector, we were able to track the tumor progression during the treatment period. Mice treated with JQ1 did not show any signs of adverse effect to the drug, indicating that JQ1 was safe and well tolerated at a daily dosage of 50 mg/kg (IP). While some of the mice in treatment group showed decreasing tumor growth compared to the control group, tumor growth trends in the two groups were not consistent, suggesting that we have to optimize the model and the treatment protocol as well as to evaluate combination treatments with bortezomib and JQ1 in in vivo models.
Citation Format: Ya-Ting Yang, Vilma Yuzbasiyan-Gurkan. Synergistic effects of Bortezomib and JQ1 for human and canine osteosarcoma treatments [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4032. doi:10.1158/1538-7445.AM2017-4032
Abstract 4054: Development of dual function small molecules as therapeutic agents for cancer treatment
Authors: Grindrod Scott , Velena Alfredo , Jung Mira 
Published: July 2017

Abstract
Inhibitors of histone deactylases (HDACs) are emerging as potent anti-cancer agents for treatment of patients with hematopoietic and solid tumors. However, most of these compounds exhibit limitations, including off-targets and toxicity. To improve the efficacy and target specificity of drugs, we developed the compound, SP-1-161 conferring HDAC inhibition activity and ataxia-telangiectasia mutated (ATM) activation. The purpose of this study is to develop a therapy that optimizes the protective effects of ATM activation in normal tissue with the sensitizing effects of HDAC inhibition in cancerous tissue into a single molecule. The compound SP-1-161 was rationally designed by optimizing ATM activation by the cap domain of a hydroximic acid, screened against a panel of Class I and Class II HDAC enzymes, and identified as a pan-HDAC inhibitor with nanomolar potency (IC50 = 8 nM). Western analysis confirms that SP-1-161 increases acetylated histone H3/H4 and α-tubulin and ATM activation in MCF7 cells. Phosphorylated ATM was gradually increased within 1 - 4 hrs in a time-dependent manner. SP-1-161 was then tested in normal breast epithelial (184A1) and breast cancer (MCF7) cell lines to determine its cytotoxicity and effect on radiation clonogenic survival in combination with graded radiation exposure. The data showed that the cytotoxicity values (IC50) were low micro-molar ranges. Furthermore, SP-1-161 protected 184A1 cells (from D0 = 1 Gy to D0 = 1.4 Gy) while increasing sensitivity of MCF7 cells to IR (from D0=1.6 Gy to D0=1.12 Gy). Together, our results demonstrate that SP-1-161 is an unprecedented radio-chemo therapeutic agent for treatment of cancers while protecting normal cells.
Citation Format: Scott Grindrod, Alfredo Velena, Mira Jung. Development of dual function small molecules as therapeutic agents for cancer treatment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4054. doi:10.1158/1538-7445.AM2017-4054
Abstract 4055: Enhancing anti-PD-1 immune blockade in melanoma through selective inhibition of histone deacetylase 6
Authors: Knox Tessa , Sahakian Eva , Nair Jayakumar , Kim Jennifer , Banik Debarati , Hadley Melissa , Powers John , Cheng Fengdong , Shen Sida , Pinilla Javier , Weber Jeffrey , Kozikowski Alan , Sotomayor Eduardo , Villagra Alejandro 
Published: July 2017

Abstract
Histone deacetylases (HDACs), were originally described in a limited context as histone modifiers. New evidence has demonstrated that HDACs are also involved in a diverse range of cellular processes that are not restricted to the chromatin environment, such as the regulation of the cell cycle/apoptosis and, more recently, a modulator of immune response. However, much remains unknown about the mechanism of action of HDACs and their roles in the immune-biology of cancer. The non-specific nature of pan-HDAC inhibitors results in a narrow therapeutic window of use, limiting the dose and duration due to toxicity. Our group has focused in one specific HDAC, HDAC6, and shown that both the genetic abrogation and pharmacological inhibition of this HDAC modulates the expression of a variety of immune-regulatory proteins in the tumor microenvironment, including PD-L1, PD-L2, MHC class I, B7-H4 and TRAIL-R1. In particular, we have previously demonstrated that both pharmacological inhibition and/or genetic abrogation of HDAC6 plays a critical role in the immune check point blockade by down-regulating the expression of PD-L1 and other check-point modulators such as PD-L2, B7-H4, etc. Moreover, we have also observed that in vivo inhibition of HDAC6 reduces tumor growth in B16 and SM1 murine melanoma models within syngeneic immunocompetent hosts. Additionally, we have found that the combination of low doses of the HDAC6i Nexturastat A and checkpoint immune blockade, including anti-PD-1 and anti-CTLA4, results in an important improvement in anti-tumor immune responses as evidenced by the reduction of tumor growth when compared to treatment with individual stand-alone agents. In these studies we also evidenced an increased production of IFNγ and IL-2 in the stand-alone check-point inhibitor treatments, which leads to an upregulation of PD-L1 and PD-L2. Similar levels of IFNγ and IL-2 were found in the combination groups. However, the expression level of PD-L1 and PD-L2 were comparable to the non-treated group. Taking all together, we have found that HDAC6i could be used as a potential adjuvant in ongoing therapeutic options involving immune check-point blockade.
Citation Format: Tessa Knox, Eva Sahakian, Jayakumar Nair, Jennifer Kim, Debarati Banik, Melissa Hadley, John Powers, Fengdong Cheng, Sida Shen, Javier Pinilla, Jeffrey Weber, Alan Kozikowski, Eduardo Sotomayor, Alejandro Villagra. Enhancing anti-PD-1 immune blockade in melanoma through selective inhibition of histone deacetylase 6 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4055. doi:10.1158/1538-7445.AM2017-4055
Abstract 4056: A modulator of multidrug resistance protein 1 selectively depletes glutathione and synergizes with L-buthionine sulfoximine to sensitize MRP1-expressing cancer cells to chemotherapy
Authors: Gana Christine C. , Hanssen Kimberley , Yu Denise M. , Flemming Claudia , Norris Murray , Haber Michelle , Fletcher Jamie 
Published: July 2017

Abstract
Multidrug resistance protein 1 (MRP1) is frequently overexpressed in tumors where it effluxes chemotherapeutic agents, protecting tumor cells from chemotherapy. This is clearly illustrated in the pediatric solid tumor neuroblastoma, where MRP1 expression is highly prognostic of clinical outcome (1,2) and contributes to chemoresistance in mouse models (3). MRP1 also effluxes low levels of glutathione (GSH), a crucial intracellular antioxidant necessary to avoid damage from the reactive oxygen species induced by radiotherapy and chemotherapy and an important component of both Phase II and Phase III drug metabolism. Depletion of GSH in cancer cells would be of therapeutic value, however the GSH synthesis inhibitor L-buthionine sulfoximine (BSO) has only limited selectivity for tumor over normal cells. We have identified a novel MRP1 inhibitor, 7-methyl-5-phenyl-2-[(4-phenyl-1-piperazinyl)carbonyl]pyrazolo[1,5-a]pyrimidine, that blocks MRP1-mediated drug efflux while greatly enhancing MRP1- mediated GSH efflux and are investigating the utility of this dual-function inhibitor for the treatment of MRP1-overexpressing cancers.
Methods: Cells expressing high levels of MRP1 were treated with MRP1 drug substrates in combination with MRP1 inhibitors. Viability was assessed by short-term cytotoxicity or clonogenic assays and GSH levels determined by glutathione recycling assay.
Results: Our MRP1 modulator depleted intracellular GSH in an MRP1-dependent manner and sensitized MRP1-expressing human neuroblastoma, lung and ovarian cancer cell to chemotherapeutics. This effect was highly synergistic with BSO, both in depleting GSH (CI&lt;0.36, p&lt;0.05) and abolishing colony formation (CI&lt;0.01, p&lt;0.05).
Conclusion: Our MRP1 modulator blocks MRP1- mediated drug efflux while greatly enhancing MRP1- mediated GSH efflux in MRP1 expressing cells, potentially providing an increased therapeutic window for chemotherapeutics in MRP1- overexpressing cancers. Synergy with BSO could widen the range of drugs and cancers that this could be beneficial for.
References 1. Haber, M., et al., (2006) J.Clin Oncol 24, 1546-1553 2. Norris, M. D., et al., (1996) New Engl J Med 334, 231-238 3. Burkhart, C. A., et al., (2009) Cancer Res 69, 6573-6580
Citation Format: Christine C. Gana, Kimberley Hanssen, Denise M. Yu, Claudia Flemming, Murray Norris, Michelle Haber, Jamie Fletcher. A modulator of multidrug resistance protein 1 selectively depletes glutathione and synergizes with L-buthionine sulfoximine to sensitize MRP1-expressing cancer cells to chemotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4056. doi:10.1158/1538-7445.AM2017-4056