bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 506: A bespoke screening platform to study mono(ADP-ribosylation)
Authors: Wigle Tim J. , Blackwell Danielle J. , Schenkel Laurie B. , Ren Yue , Church William D. , Desai Hetvi J. , Swinger Kerren K. , Santospago Andrew G. , Majer Christina R. , Lu Alvin Z. , Niepel Mario , Perl Nicholas R. , Vasbinder Melissa M. , Keilhack Heike , Kuntz Kevin W. 
Published: September 2020

Abstract
Mono(ADP-ribosylation) (MARylation) and poly(ADP-ribosylation) (PARylation) are post-translational modifications deposited on multiple amino acids by PARP enzymes using nicotinamide adenine dinucleotide (NAD+) as the ADP-ribose donating substrate. While there are approved drugs and clinical trials on-going for inhibitors of the polyPARP enzymes that deposit poly(ADP-ribose) (specifically PARP1 and PARP2 inhibitors), monoPARP enzymes that deposit mono(ADP-ribose) are only recently gaining recognition for their role in cellular stress signaling, inflammation and cancer. However, there is a lack of chemical probes to study their function in cells and in vivo. An important first step to generating chemical probes for monoPARPs is to develop screening assays to enable determination of potency and selectivity of inhibitors during the hit finding and lead optimization phases. The development of enzyme assays is complicated by the fact that the substrates for the majority of the monoPARPs are unknown, and even for those with identified substrates, it is uncertain how they engage their substrates. Here we describe the development of robust high-throughput biochemical and cellular monoPARP assays that overcome the lack of knowledge around the substrates and construction of a family-wide screening panel. We highlight derivatized microplates that activate the enzymes to self-MARylate in dissociation enhanced lanthanide fluorescence assays (DELFIA), antibodies that recognize MARylation in in-cell western (ICW) and immunofluorescence (IF) assays, and NAD+-competitive molecular probes that are used to develop in vitro time-resolved fluorescence resonance energy transfer (TR-FRET) and cellular NanoLuc bioluminescence resonance energy transfer (NanoBRET) probe displacement assays. Additionally, we employ several methods to characterize inhibitor binding kinetics. These assays have been used in high-throughput screening campaigns of up to 500,000 compounds, as well as in the development of potent and selective inhibitors of multiple monoPARP enzymes including RBN012759, a tool compound for PARP14 that inhibits in vitro with an IC50 of 3 nM and in cells using with an IC50 of 9 nM, and is 300-fold selective over all other PARP enzymes.
Citation Format: Tim J. Wigle, Danielle J. Blackwell, Laurie B. Schenkel, Yue Ren, William D. Church, Hetvi J. Desai, Kerren K. Swinger, Andrew G. Santospago, Christina R. Majer, Alvin Z. Lu, Mario Niepel, Nicholas R. Perl, Melissa M. Vasbinder, Heike Keilhack, Kevin W. Kuntz. A bespoke screening platform to study mono(ADP-ribosylation) [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 506.
Abstract 5070: LIN28A-mediated repression of Let-7a is involved in resistin-induced STAT3 upregulation in breast cancer cells and supports growth and stemness properties
Authors: Deshmukh Sachin Kumar , Srivastava Sanjeev K. , Zubair Haseeb , Singh Ajay P. , Singh Seema 
Published: September 2020

Abstract
Breast cancer (BC) is the most frequently diagnosed malignancy and continues to be the second leading cause of cancer-related death in women in the United States. Dysregulation of Let-7 family microRNAs is observed in BC and associated with disease pathogenesis. Previously, we reported a significant increase in serum levels of resistin in BC patients as compared to the healthy individuals. Moreover, this increase was significantly greater in BC patients of African American background as compared to those of European descent. We also demonstrated that treatment of BC cells with resistin promoted their growth, aggressiveness, stemness and chemoresistance by inducing the expression and activation of STAT3. Here we present data to show that resistin induces STAT3 expression in BC cells in a LIN28A and Let-7a-dependent manner. Treatment of BC cells with resistin led to the most significant decrease in the expression of Let-7a among other Let-7 family members. Furthermore, resistin treatment also induced the expression of LIN28A at both transcript and protein levels and its silencing abrogated resistin-mediated Let-7a suppression. Let-7a restoration or LIN28A silencing abolished the resistin-induced growth, clonogenicity and sphere-forming ability of BC cells. Restoration of Let-7a suppressed the expression of several genes associated with growth, survival and stemness. Ingenuity Pathway Analysis suggested STAT3 as a putative central node associated with Let-7a-mediated gene regulation. Immunoblot analysis confirmed that Let-7a restoration dramatically suppressed basal as well as resistin-induced STAT3 expression. STAT3 regulation by Let-7a was further confirmed 3'UTR-reporter assay. Taken together, our findings demonstrate a novel resistin/LIN28A/Let-7a/STAT3 signaling axis regulating the growth and stemness phenotypes of BC cells.
Citation Format: Sachin Kumar Deshmukh, Sanjeev K. Srivastava, Haseeb Zubair, Ajay P. Singh, Seema Singh. LIN28A-mediated repression of Let-7a is involved in resistin-induced STAT3 upregulation in breast cancer cells and supports growth and stemness properties [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5070.
Abstract 508: A novel orally available Wnt-pathway inhibitor for the treatment of metastatic cancers
Authors: Zhou Kun , Cheong Jae Eun , Alix-Panabières Catherine , Sun Lijun , Zetter Bruce R. 
Published: September 2020

Abstract
We have developed a novel drug compound (OBD9) which blocks growth of metastatic cancer cells both in vitro and in vivo. We now identify OBD9 as an effective Wnt-signaling inhibitor targeting TNIK (TRAF2 And NCK Interacting Kinase) and we hypothesize that OBD9 represent a novel therapeutic option for patients with tumors that have an activated Wnt signaling pathway.
To find novel drug candidates that selectively inhibit metastatic tumor cell viability, a drug screen was firstly performed and results of the screen identified members of the FDA-approved benzimidazole methylcarbamate family (e.g. mebendazole (MBZ) and albendazole (ALB)) as potential therapies for metastatic cancer. Earlier work also supports a role for this chemical family in the potential treatment of multiple cancers, but progress has been stalled by their poor water solubility and poor bioavailability for systemic delivery to disseminated tumors. We therefore synthesized a novel compound (OBD9) containing the scaffold of MBZ coupled to an oxetane group to enhance aqueous solubility to 361μM. OBD9 demonstrates significant cytotoxicity toward a variety of cancer cell types including colon, lung, and prostate cancers (IC50: 0.9-2μM). In a mouse xenograft model using highly aggressive PCMLN3 prostate cancer cells, OBD9 at 30 mg/kg significantly repressed growth of established tumors with no visible toxicity. In a mouse xenograft model of human A549 lung cancer cell line, orally delivered OBD9 also dramatically inhibited the growth of established tumors at 30 or 90μM without noticeable toxicity.
Mechanistically, we find that OBD9 treatment significantly reduces TNIK levels as early as 4 hours at 1uM via an autophagy-dependent protein degradation pathway. TNIK functions as an activator of Wnt signaling pathway via phosphorylation of the beta-catenin/TCF4 complex that regulates Wnt downstream targets. We show that OBD9 treatment inhibits colon cancer cell growth and both qPCR and Western blot data suggest that Wnt signaling downstream targets, such as TCF4, AXIN2 and cMyc, are all significantly suppressed by OBD9 via the inhibition of TNIK. Overall, our in vitro and in vivo data suggest that OBD9 potentially represents a novel therapeutic option for multiple cancers including but not limit to colon, lung and prostate cancer.
Citation Format: Kun Zhou, Jae Eun Cheong, Catherine Alix-Panabières, Lijun Sun, Bruce R. Zetter. A novel orally available Wnt-pathway inhibitor for the treatment of metastatic cancers [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 508.
Abstract 5108: Investigation of how extracellular matrix composition affects pancreatic cancer chemoresistance through the use of biomimetic models
Authors: Xiao Weikun , Eun Chae-Young , Dekalb Charlene , Zhang Kexin , Hill Reginald 
Published: September 2020

Abstract
Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal and malignant type of cancer with few effective treatments. Despite recent advancement in knowledge of cancer treatment, median survival of PDAC patients remains within 2 years, and less than 8% patients live beyond 5 years after diagnosis. The main factor that drives PDAC lethality is the development of chemoresistance in nearly all clinical PDACs. While intrinsic factors that facilitates chemoresistance have been studied extensively, few studies have illustrated how complex and unique microenvironment surrounding the PDAC tumor affects therapeutic responses. Moreover, a physiologically relevant co-culture model of PDAC and stromal cells remained challenging. To address this issue, we have developed a Matrigel-based, orthogonally tunable 3-dimensional (3D) culture system to culture established human PDAC cell lines, cancer-associated fibroblast (CAF) cells and mouse model-derived organoids. Individual matrix parameters can be customized to mimic actual tumor matrix composition and mechanical properties. Moreover, we have optimized a co-culture medium to maintain viability of both organoid tumor and cancer associated fibroblasts. Through our 3D culture system, our data suggests that matrix-induced exosome secretion directly facilitate gemcitabine resistance in PDAC cells. By directly increasing stiffness of our 3D culture platform, we have observed that PDAC cells potentially display more invasive phenotype. Moreover, in the co-culture systems, we have seen that CAF cells cultured in different stiffness substrates affect PDAC drug response in organoid cultures. Our investigation provides insight into how matrix composition and stiffness together affect therapeutic outcome in PDAC. We believe that specific therapeutic strategies aimed at targeting the matrix microenvironment will be instrumental in order to overcome matrix-mediated chemoresistance in PDAC.
Citation Format: Weikun Xiao, Chae-Young Eun, Charlene Dekalb, Kexin Zhang, Reginald Hill. Investigation of how extracellular matrix composition affects pancreatic cancer chemoresistance through the use of biomimetic models [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5108.
Abstract 5112: Interaction between RHOA mutated gastric cancer cells and cancer associated fibroblasts promotes tumorigenesis
Authors: Jeon Daye , Choi Yuri , Lee Seon Jin , Choi Kyung Un , Park Do Youn , Kwon Chae Hwa 
Published: September 2020

Abstract
Background: We previously observed that RHOA-mutated gastric cancer has desmoplastic morphological feature. Although desmoplastic reaction is known to consist mainly of cancer associated fibroblasts (CAF), the relationship cancer cells with RHOA mutation and CAF have not been reported. Thus, in this study, we investigated the interaction between RHOA-mutated gastric cancer cells and CAF and its underlying mechanism.
Methods: We established stable gastric cell lines (AGS, MKN-45) expressing RHOA wild type (WT) of mutation (G17E, T37I, E40K, Y42C) using lentiviral vector and cocultured these cells with CAF using transwell. And proliferation and migration of RHOA-mutated gastric cancer cells were examined. To understand molecular mechanism of RHOA-mutated gastric cancer cells proliferation and migration, RNA-sequencing was conducted and the results were analyzed and validated.
Results: Cocultivation of gastric cancer cells expressing RHOA WT or mutation (G17E, T37I, E40K, Y42C) with CAF increased proliferation relative to cells expressing an empty vector (EV). In addition, migration of RHOA mutant cells, except for cells with RHOA WT and Y42C, was increased by CAF relative to EV cells. Genes related to IL-17, IL-15, and IGF-1 signaling pathways were differentially expressed between RHOA WT or mutant cells and EV cells, suggesting that proliferation and migration of RHOA mutant cells promoted by CAF through these pathways. Furthermore, we identified CXCL1 and IGFBP2 as mediator of interaction between RHOA mutated gastric cancer cells and CAF.
Conclusion: In summary, we found that gastric cancer cells with RHOA mutation have tumor-promoting activity by interaction with CAF. Thus, molecules for impairing their interactions could be potential therapeutic targets in gastric cancer patients with RHOA mutation.
Citation Format: Daye Jeon, Yuri Choi, Seon Jin Lee, Kyung Un Choi, Do Youn Park, Chae Hwa Kwon. Interaction between RHOA mutated gastric cancer cells and cancer associated fibroblasts promotes tumorigenesis [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5112.
Abstract 5130: Proteomic characterization of cytoplasmic lipid droplets in human metastatic breast cancer cells
Authors: Zembroski Alyssa S. , Andolino Chaylen , Buhman Kimberly K. , Teegarden Dorothy 
Published: September 2020

Abstract
One of the characteristic features of metastatic breast cancer is altered lipid metabolism, including increased cellular storage of neutral lipid in cytoplasmic lipid droplets (CLDs). CLD accumulation is associated with increased cancer aggressiveness, suggesting CLDs contribute to metastasis. Although multiple hypotheses exist for how CLDs may promote cancer progression, how exactly CLDs contribute to breast cancer metastasis is not clear. CLDs are composed of a neutral lipid core, a phospholipid monolayer, and associated proteins. Proteins that associate with CLDs are thought to regulate CLD metabolism; however, the proteome of CLDs in metastatic breast cancer and how these proteins may contribute to altered lipid metabolism and breast cancer progression is unknown. Therefore, we utilized untargeted shotgun proteomics and transmission electron microscopy to identify the proteome and assess the characteristics of CLDs in the MCF10CA1a human metastatic breast cancer cell line. We identified a total number of 1537 proteins in the CLD fraction isolated from MCF10CA1a cells, and these proteins were associated with a variety of cellular processes. Interestingly, unlike other cell lines such as adipocytes or enterocytes, the most enriched protein categories were involved in cellular processes outside of lipid metabolism. For example, proteins involved in cell-cell adhesion were the most enriched in the CLD fraction, and some of these proteins had associated terms in cell migration and signaling. In addition, we characterized CLD size and area in MCF10CA1a cells using transmission electron microscopy. Our results provide a hypothesis-generating list of potential players in breast cancer progression and aggressiveness, making them possible therapeutic targets for prevention or treatment of this disease.
Citation Format: Alyssa S. Zembroski, Chaylen Andolino, Kimberly K. Buhman, Dorothy Teegarden. Proteomic characterization of cytoplasmic lipid droplets in human metastatic breast cancer cells [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5130.
Abstract 5133: Optimized RAS top-down proteomic assay reveals expanded proteoform landscape in malignant cells
Authors: DeHart Caroline , Sharma Kanika , Esposito Dominic , Maciag Anna , Nissley Dwight , McCormick Frank 
Published: September 2020

Abstract
Traditional proteomic methods face an inherent challenge with the RAS family of GTPases (HRAS, NRAS, KRAS4A, KRAS4B). Expressed at low endogenous abundance, these four isoforms possess considerable sequence similarity, rendering the confident proteomic linkage of a given isoform with a specific mutation or post-translational modification (PTM) a formidable proposition outside of isoform-specific model cell lines. Conversely, top-down proteomic analysis (TDP), which measures intact protein molecules, can precisely identify modified protein forms, or proteoforms, and confidently localize both mutations and PTMs on each RAS isoform present. Previously, a method combining immunoprecipitation and subsequent TDP (IP-TDP) led to the identification of eleven KRAS4B proteoforms, including four mutations and two novel PTMs, within colorectal cancer cell lines and tumor samples†. These initial results demonstrated the great potential for proteoform-resolved measurements to further illuminate the role of KRAS4B mutations and modifications in human cancer.
More recently, the NCI RAS Initiative has developed an enhanced RAS proteoform assay incorporating IP-TDP analysis on an Orbitrap Fusion Lumos mass spectrometer. By employing alternate antibodies, recombinant protein standards, and well-characterized model or malignant cell lines, we have obtained substantial improvements in both RAS proteoform detection and characterization, thus facilitating the identification and localization of low-abundance PTMs. Moreover, we have applied our optimized IP-TDP method to a diverse panel of malignant and RAS mutant cell lines with the goal of expanding our knowledge of the RAS proteoform landscape. In doing so, we have observed a wealth of novel RAS proteoforms, of far greater number and complexity than previously anticipated. We have also observed isoform-specific proteoform variations, most notably between KRAS4A and KRAS4B, and initial indications of proteoform context dependence, namely within a given mutation or tissue background. Our results further underscore the power of proteoform-resolved measurements and indicate that RAS-dependent signaling pathways in normal and cancer contexts may be far more complex than previously thought.
† I Ntai et. al. “Precise characterization of KRAS4b proteoforms in human colorectal cells and tumors reveals mutation/modification crosstalk.” Proc Natl Acad Sci U S A. 2018 Apr 17; 115(16):4140-4145.
Citation Format: Caroline DeHart, Kanika Sharma, Dominic Esposito, Anna Maciag, Dwight Nissley, Frank McCormick. Optimized RAS top-down proteomic assay reveals expanded proteoform landscape in malignant cells [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5133.
Abstract 5152: SJP1604, a nucleolin-targeted therapeutic agent for relapsed/refractory acute myeloid leukemia
Authors: Um Jihyun , Lee Dohyeong , Park Yongbin , Moon Sung Hwan , Lee Soo Jin , Ki Min-Hyo 
Published: September 2020

Abstract
Acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) are cancers characterized by the rapid growth of abnormal white blood cells. Although the standard first-line therapy leads to high rates of remission, approximately 30% of the treated patients are refractory and more than 50% of them face a relapse because of the occurrence of drug resistance and high toxicity. Therefore, there is a strong unmet medical need for the next-generation targeted therapy to overcome drug resistance and reduce toxicity in AML/MDS. Here, we designed an aptamer-drug conjugate (SJP1604) specific for nucleolin, which is highly expressed only on the cell membrane of cancer cells including AML cells. We identified that SJP1604 (APTA-16) inhibited the growth of AML cells and drug-resistant AML cells in vitro. SJP1604 presented outstanding anti-leukemic efficacy in vivo via syngeneic mouse model and xenograft mouse model. In addition, the synergistic effects were observed upon combination treatmeant with venetoclax in vitro. We also figured out that nucleolin as a clinical biomarker was significantly highly expressed on relapsed/refractory (R/R) AML patient-derived bone marrow cells ex vivo. SJP1604 selectively targeted cancer cells by nucleolin-binding on cell membrane with its high targeting ability and plasma stability owing to its unique conformational property, therefore, it demonstrated less cytotoxicity in vitro/in vivo and a superior therapeutic index based on AUC comparison in pharmacokinetic studies. The mechanism of the anti-leukemic efficacy of SJP1604 was also studied. First of all, SJP1604 decreased the expression of nucleolin and inactivated NFκB signaling pathway via dephosphorylation of NFκB, which resulted in diminished expression of DNMT1 followed by restored p15 expression. In addition, SJP1604 increased p53 expression and decreased bcl-2 expression in the protein and mRNA level. These could be one of potential mechanism of anti-leukemogenesis of SJP1604. In conclusion, these findings suggest that SJP1604 targeting nucleolin could be developed as a first-in-class drug for relapsed/refractory AML and MDS. GLP safety/toxicology studies of SJP1604 have been completed and clinical trials will be initiated in 2020.
Citation Format: Jihyun Um, Dohyeong Lee, Yongbin Park, Sung Hwan Moon, Soo Jin Lee, Min-Hyo Ki. SJP1604, a nucleolin-targeted therapeutic agent for relapsed/refractory acute myeloid leukemia [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5152.
Abstract 5182: Examining the effects of honokiol on EGFR-positive glioblastoma multiforme
Authors: Smith Keller , Johnson Blake 
Published: September 2020

Abstract
Glioblastoma (GBM) is a highly aggressive and lethal form of primary brain tumor. Systemic suppression of the immune system, specifically T-cell impairment, significantly contributes to GBM development and progression. Recent advances in cancer immunotherapies have shown great promise in alleviating such tumor-associated immunosuppression, namely programmed cell death 1 (PD-1)/programmed death ligand 1 (PD-L1) checkpoint inhibitors. Regrettably, early clinical studies evaluating the efficacy of checkpoint inhibition in recurrent GBM have rendered only modest improvements in overall survival rates, due partially to insufficient inhibition of AKT-STAT3 pathways which are often dysregulated downstream of hyperactive epidermal growth factor receptors (EGFR) in GBM. In the current study, we aim to evaluate a newly discovered small molecule inhibitor of AKT-STAT3, honokiol, and its ability to suppress AKT-STAT3 activity in the context of hyperactive EGFR in GBM. Using U87-MG cells that stably overexpress a common hyperactivating mutation of EGFR, EGFRvIII, we have preliminary evidence that honokiol is an effective inhibitor of U87-EGFRvIII cellular migration as a result of its robust AKT-STAT3 pathway suppression. Thus, honokiol may provide a novel means of pharmacological inhibition of AKT-STAT3 hyperactivity in GBM and therefore greater clinical efficacy of immune checkpoint inhibitors in this deadly disease.
Citation Format: Keller Smith, Blake Johnson. Examining the effects of honokiol on EGFR-positive glioblastoma multiforme [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5182.