bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 3945: Novel antagonists of TEAD palmitoylation inhibit the growth of Hippo-altered cancers in preclinical models
Authors: Kamal Adeela , Candi Aurélie , Versele Matthias , Vanderhoydonck Bart , Marchand Arnaud , de Jong Ron , Hoang Thuy , Halder Georg , Chaltin Patrick , Gwaltney Stephen L. , Burgess Mike 
Published: June 2022

Abstract
Background: The Hippo pathway is an evolutionarily conserved signaling cascade whose deregulation can promote excessive cell proliferation and tumor development. Pathway output is mediated by the YAP and TAZ transcriptional co-activators, which bind to TEAD family transcription factors to drive target gene expression. Genomic aberrations in Hippo pathway components result in constitutive activation of YAP/TAZ, as seen with NF2 mutations in subsets of mesothelioma and other cancers. Hyperactivation of YAP/TAZ has also been associated with resistance to a variety of targeted agents, including EGFR and CDK4/6 inhibitors, suggesting that targeting the pathway may have utility as part of rationally selected combinations, in addition to genomically-informed monotherapy applications. Activity of the YAP/TAZ-TEAD complex thus represents a compelling pharmacologic target, due to its essential role in the pathway, and the presence of a conserved druggable site in TEAD that is required for transcriptional function.
Results and Discussion: Using biophysical techniques, we identified novel small molecules that bind to the TEAD auto-palmitoylation pocket. Initial hits were optimized for antagonism of TEAD-based transcription and drug-like properties, ultimately producing highly potent and orally bioavailable TEAD inhibitors. These compounds selectively inhibited the proliferation of cancer cell lines harboring genomic alterations in the Hippo pathway with low nM potency. In vivo models of Hippo pathway-altered xenografts showed consistent monotherapy activity, with dose-dependent and durable tumor regressions achieved at well-tolerated doses. Further characterization of these compounds as monotherapies and as part of rationally-designed combination regimens is ongoing.
Citation Format: Adeela Kamal, Aurélie Candi, Matthias Versele, Bart Vanderhoydonck, Arnaud Marchand, Ron de Jong, Thuy Hoang, Georg Halder, Patrick Chaltin, Stephen L. Gwaltney, Mike Burgess. Novel antagonists of TEAD palmitoylation inhibit the growth of Hippo-altered cancers in preclinical models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3945.
Abstract 3949: Identification of a novel HASPIN inhibitor and the synthetic lethal partner by computational analysis
Authors: Kwon Eun-Ji , Mashelkar Karishma , Lee Hyuk Woo , Shin Yoon-Ze , Jeong Lak Shin , Cha Hyuk-Jin 
Published: June 2022

Abstract
HASPIN, a mitotic kinase to phosphorylate Histone H3 at centromere, has been studied as a promising target for anti-cancer therapy. However, as HASPIN belongs to atypical kinase, lacking the Asp-Phe-Gly (DFG) motif, development from the chemical library of kinase inhibitors with conventional pharmacophore, would be technically challenging. In particular, one of adenosine analogues (LJ4827), a potent inhibitor of multi-kinases, showing clear anti-cancer activity in vitro and in vivo, was predicted as a HASPIN inhibitor by computation analysis of its transcriptome profile in cancer cells to drug-omic data set in the connectivity MAP (cMAP) as it shared similar transcriptome profile of 5-iodotubercidin (5ITU). The specificity and potency as HASPIN inhibitor of LJ4827 (IC50 = 0.45 nM) validated by in vitro kinase screening and consequent 3D structure modeling. As expected, treatment of LJ4827 in cancer cell lines efficiently delayed mitotic progression without double strand break (DSB) unlike 5ITU and significantly attenuated Aurora B localization at centromere. Along with clinical significance of HASPIN expression in lung cancer patients, mitotic gene signature closely associated to high expression of HASPIN, revealed the poor prognosis. Additional computational analysis of kinase perturbation data to predict the dependency of mitotic kinase in the absence of HASPIN activity, revealed the synthetic lethal effect of cotreatment of the chemical inhibitor of BUB1, PLK1 or AURKA with LJ4827. These data suggest that combined inhibition of HASPIN with the novel inhibitor and key mitotic kinases for centromere/kinetochore regulation would be effectivity therapeutic approach for cancer therapy.
Citation Format: Eun-Ji Kwon, Karishma Mashelkar, Hyuk Woo Lee, Yoon-Ze Shin, Lak Shin Jeong, Hyuk-Jin Cha. Identification of a novel HASPIN inhibitor and the synthetic lethal partner by computational analysis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3949.
Abstract 3961: Cancer stem cells, not bulk tumor cells, predict mechanisms of resistance to SMO inhibitors in SHH medulloblastoma
Authors: George Joshy , Chen Yaohui , Abdelfattah Nourhan , Yamamoto Keiko , Adamson Scott , Choi Jong Min , Rybinski Brad , Srivastava Anuj , Kumar Parveen , Lee Min Gyu , Baskin David S. , Jiang Wen , Kim Betty Y. , Flavahan William , Chuang Jeffrey H. , Jung Sung Yun , Yun Kyuson 
Published: June 2022

Abstract
The emergence of primary and acquired treatment resistance significantly reduces the clinical utility of many effective targeted therapies. Both genetic and epigenetic mechanisms of drug resistance have been reported in literature; however, whether these mechanisms are stochastically selected in individual tumors or governed by a predictable underlying principle is unknown.Here, we report that one can predict a priori the resistance mechanism that will arise in individual SMO inhibitor (SMOi)-resistant SHH medulloblastoma (MB), based on different CSC phenotypes in each tumor. We show that the dependence of cancer stem cells (CSCs), not bulk tumor cells, on the targeted pathway (sonic hedgehog (SHH) pathway) determines the molecular mechanism of resistance in individual tumors. Using both spontaneous (Fsmo;GFAP-cre) and transplantable (Ptch+/-;p53) mouse models of SHH MB treated with a Smoothened inhibitor, sonidegib/LDE225, we show that genetic-based resistance occurs only when the CSCs depend on the targeted pathway. In contrast, SHH MBs containing SHH-dependent bulk tumor cells but SHH-independent CSCs (SI-CSCs), acquire resistance through epigenetic reprogramming. Mechanistically, we discovered that the elevated proteasome activity in SMOi-resistant SI-CSC MBs alters the tumor cell maturation trajectory through enhanced degradation of specific epigenetic regulators, including the histone acetylation machinery. Consequently, SMOi-resistant SI- SMOi-resistant SI-CSC exhibit a global reduction of H3K9Ac, H3K14Ac, H3K56Ac, H4K5Ac, and H4K8Ac marks and gene expression changes. These results provide new insights into how selective pressure on distinct tumor cell populations contributes to different mechanisms of resistance to targeted therapies and implicate histone acetylation in the process. This information can be clinically exploited to understand responses and resistance to SMOis and other targeted therapies.
Citation Format: Joshy George, Yaohui Chen, Nourhan Abdelfattah, Keiko Yamamoto, Scott Adamson, Jong Min Choi, Brad Rybinski, Anuj Srivastava, Parveen Kumar, Min Gyu Lee, David S. Baskin, Wen Jiang, Betty Y. Kim, William Flavahan, Jeffrey H. Chuang, Sung Yun Jung, Kyuson Yun. Cancer stem cells, not bulk tumor cells, predict mechanisms of resistance to SMO inhibitors in SHH medulloblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3961.
Abstract 3962: Mechanisms of tumor recurrence and drug resistance in rhabdomyosarcoma
Authors: Moonamale Devmini C. , Wachtel Marco , Schäfer Beat W. 
Published: June 2022

Abstract
Rhabdomyosarcoma (RMS) is an aggressive pediatric soft tissue sarcoma, which constitutes of two main histological subtypes. Alveolar Rhabdomyosarcoma (FP-RMS) is characterized by a fusion protein PAX3-FKHR, whereas embryonal Rhabdomyosarcoma (FN-RMS), which is the focus of this project, is more genetically heterogeneous. The prognosis for RMS has improved over the years, however the cure rates for recurrent or relapse disease remains dismal, warranting further identification of novel therapeutic interventions, which is the aim of this project. To this end, we performed two CRISPR knockout screens, using a kinome sgRNA library and a whole genome sgRNA library in combination with etoposide at a concentration of IC10, in order to identify genes that might confer resistance to chemotherapeutic drugs. In addition, the kinome screen was also designed to identify essential genes by using the treatment control samples as further time points. For treatment associated genes, we identified components of the JNK/P38 and Hippo signaling pathways among the top hits. We also found enrichment of a novel pathway involving HIFα stabilization via the genes LRRK2 and PTK6. Further and as expected, many DNA damage repair pathways were enriched. Finally in this category, players of the Wnt signaling pathway including JNK1, which is involved in non-canonical Wnt signaling were found to be enriched. As for essential gene identification, many cell cycle genes such as CDK6, PLK3 and PLK4 were among the top hits, as well as WEE1, which has been implicated in the context of RMS, were common between all the time points. Taken together, the CRISPR screens identified potential pathways that might be involved in resistance of FN-RMS cells towards etoposide. Selected candidates are being validated via an in vitro competition assay and drug screening is being performed to identify inhibitors that could be used to re-sensitize cells to treatment with standard chemotherapy.
Citation Format: Devmini C. Moonamale, Marco Wachtel, Beat W. Schäfer. Mechanisms of tumor recurrence and drug resistance in rhabdomyosarcoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3962.
Abstract 3965: Histone H3 K27M mediated regulation of cancer cell stemness and differentiation in diffuse intrinsic pontine glioma (DIPG)
Authors: Sharma Monika , Magnuson Brian , Cruz Jeanette , Kauss McKenzie , Buschhaus Alexander , Ljungman Mats , Galban Stefanie 
Published: June 2022

Abstract
Diffuse Intrinsic Pontine Glioma (DIPG) is a rare pediatric brain tumor with a median survival of 10-15 months. Histone H3 is mutated in 80% of DIPGs, dictating tumor location, onset, and outcome of this devastating disease. Therapeutic resistance remains a major obstacle to preventing tumor recurrence and is in part driven by cancer stem cells (CSCs), which exhibit self-renewal properties and tumorigenic potential. In previous studies, we have identified these proliferative and tumorigenic features in aldehyde dehydrogenase positive (ALDH+) CSCs in H3K27M mutant DIPG. Among the 19 ALDH isoforms known in humans, aldehyde dehydrogenase family 1 member A3 (ALDH1A3) is most highly expressed in malignant cells when compared to immune cells or oligodendrocytes in H3K27M DIPG biopsies, indicating an important mechanistic role in regulating stemness in DIPG. We hypothesize that ALDH-mediated cancer stemness and resistance may in part be driven by H3K27M. Indeed, ALDH1A3 expression was dramatically reduced in CRISPR-edited DIPG cells where the H3K27M mutation had been removed (H3K27M-KO). Furthermore, these cells lost their neurosphere forming potential, began to express glial fibrillary acidic protein (GFAP) and attached to the plastic, changes indicative of differentiation. Transcriptomic and GSEA pathway analyses suggested Wnt-dependent regulation of ALDH1A3, with Wnt 7b and Wnt 11 demonstrating the largest difference in the isogenic DIPGs. In addition, DNA repair, along with PI3K/AKT and Wnt signaling, were found to be upregulated upon radiation of DIPG cells, indicating future therapeutic opportunities to prevent radio resistance. We have co-targeted these cell-intrinsic vulnerabilities to eradicate CSCs in DIPG and prevent tumor recurrence, using a combination of radiotherapy, the PI3K/mTOR inhibitor GDC-0084 and the ALDH inhibitor Disulfiram. This combination has produced an exquisite synergy in cells, which we will test in clinically-relevant DIPG models. Taken together, through these studies we have gained mechanistic insight into H3K27M mediated regulation of cancer cell stemness and differentiation in DIPG, which appears to be mediated by Wnt-dependent signaling of ALDH1A3 and provides rationale for exploring new therapeutic targets.
Citation Format: Monika Sharma, Brian Magnuson, Jeanette Cruz, McKenzie Kauss, Alexander Buschhaus, Mats Ljungman, Stefanie Galban. Histone H3 K27M mediated regulation of cancer cell stemness and differentiation in diffuse intrinsic pontine glioma (DIPG) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3965.
Abstract 3974: Investigating doxorubicin resistance in fibrosarcoma
Authors: Dorand Rodney Dixon , Dang Donna , Davis Elizabeth J. , Park Ben Ho 
Published: June 2022

Abstract
Cytotoxic chemotherapy has been the backbone of medical oncology for nearly a century for multiple cancer types. However, when treating advanced or metastatic disease toxicity, side effects, and acquired resistance often limit the duration of therapy. While randomized control trials have traditionally served as the proving ground for first and subsequent line therapies, rare tumor subtypes including soft tumor sarcoma (STS) provide unique challenges for developing robust treatment data. By developing human based in vitro models, we can investigate potential therapeutic mechanisms for STS. Fibrosarcoma is one distinct histologic STS subtype that relies heavily on anthracycline treatment in the first line setting, however, there are limited options once resistance develops. Anthracyclines, including doxorubicin, exert their effect through a variety of mechanisms including reactive oxygen species, DNA-adduct formation, and inhibiting topoisomerase II, histone eviction, calcium and iron homeostasis, and ceramide overproduction. However, there have also been multiple mechanisms of doxorubicin resistance including disruption of cell membrane, alteration of cell surface molecules, inactivation of drugs, gene amplification, activating alternative signaling pathways, and affecting cellular repair mechanisms. In order to investigate the role of anthracycline resistance in fibrosarcoma lines we acquired two human derived fibrosarcoma lines SW684 and HT-1080 from American Type Culture Collection (ATCC). Characterization of HT-1080 using publicly available datasets demonstrated that TP53, CDK2NA and NF1 serve as major driver mutations while SW684 relies on NRAS and IDH1 mutations. We further characterized these cell lines in vitro and noted that HT-1080 has a quick doubling time of 16 hours while SW684 has a doubling time of 91 hours. Additionally, after doxorubicin treatment, we found that HT-1080 is sensitive with an IC50 of 5.594 nanomolar while SW684 is relatively doxorubicin resistant with an IC50 of 28.915 micromolar. While proliferative rate may play a role in the sensitivities of these cell lines further characterization of the mechanism leading to doxorubicin resistance is needed. To that end, we are using a CRISPR-Cas9 approach for further genome wide screening of these fibrosarcoma lines in the presence of doxorubicin. Exploring the genetic mechanisms that result in development of doxorubicin resistance may reveal novel, targetable mechanisms expanding treatment durability in this rare STS.
Citation Format: Rodney Dixon Dorand, Donna Dang, Elizabeth J. Davis, Ben Ho Park. Investigating doxorubicin resistance in fibrosarcoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3974.
Abstract 4002: Identification of signal transduction pathway activity with potential clinical target in high-grade serous ovarian carcinoma
Authors: Van der Ploeg Phyllis , Wesseling-Rozendaal Yvonne J.W. , Biezen-Timmermans Eveline C. , Piek Jurgen M.J. 
Published: June 2022

Abstract
Background: High-grade serous carcinoma (HGSC) is the most common subtype of ovarian cancer. It has a high mortality rate, even after successful first-line treatment with debulking surgery and chemotherapy. Although therapeutic options for targeted therapy are rapidly expanding, identification of patients who respond to these therapies remains a challenge. In recognition of the importance of the functional phenotype of cancer cells, Verhaegh et al. (Cancer Res 2014) developed assays to measure functional activity of signal transduction pathways (STPs) based on mRNA expression levels of pathway-specific target genes. In this study, we aimed to identify HGSCs with STP activity with a potential clinical target by comparing their activity with STP activity in normal Fallopian tube epithelium (FTE), the tissue of origin of most HGSCs.
Methods: We included 50 primary tumor samples taken prior to start of chemotherapy of postmenopausal patients diagnosed with advanced stage HGSC and 9 morphologically normal FTE samples of healthy postmenopausal women. Using pathway assays, we assessed functional pathway activity of the androgen receptor (AR), estrogen receptor (ER), PI3K, MAPK, Hedgehog, TGFβ and Notch pathways. Differences in STP activity between groups were compared with Mann-Whitney U tests. Cut-off value for aberrant STP activity was defined as two standard deviations above the mean value of STP activity measured in FTE samples.
Results: In the HGSC group we observed lower median ER (p &lt; 0.001) pathway activity and higher median PI3K (p &lt; 0.001), Hedgehog (p &lt; 0.001) and TGFβ pathway (p = 0.020) activity as compared to the FTE group. In individual HGSC samples, aberrant activity was identified for the MAPK (n = 10), PI3K (n = 22), Hedgehog (n = 28) and TGFβ (n = 21) pathways. Frequently observed combinations of aberrant STP activity were Hedgehog/TGFβ (n = 12) and Hedgehog/PI3K (n = 9). In total, we identified at least one STP with potential clinical target in 88% (44/50) of HGSC samples.
Conclusions: Our analysis enabled the identification of STP activity with a potential clinical target in 88% of the analyzed HGSC samples. Differentiation between normal and aberrant STP activity could have clinical utility in the selection of HGSC patients for targeted therapy. A prospective study (STAPOVER) has been designed to demonstrate clinical utility.
Citation Format: Phyllis Van der Ploeg, Yvonne J.W. Wesseling-Rozendaal, Eveline C. Biezen-Timmermans, Jurgen M.J. Piek. Identification of signal transduction pathway activity with potential clinical target in high-grade serous ovarian carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 4002.
Abstract 4003: Identification of a targeted anti-mitotic agent that degrades Myc and specifically induces cancer cell death
Authors: McAnulty Jessica , Dziubinski Michele , Gandhi Agharnan , Farah Margaret , Lee Pil , White Andrew D. , DiFeo Analisa 
Published: June 2022

Abstract
For decades, chemotherapy has remained the standard of care for ovarian cancer patients. Although 70% of patients initially respond to platinum-based therapy, &gt;90% succumb to chemoresistance. There is a need to uncover targeted drugs for ovarian cancer. A quicker, more cost-effective, and lower-risk route to identify new treatments is through repurposing FDA approved drugs. Using a computational drug repositioning platform, DrugPredict, we previously uncovered that the antiarrhythmic drug amiodarone potently decreases cell viability and triggers apoptosis in numerous patient-derived ovarian cancer cell lines through the degradation of c-Myc. However, given the dose-limiting toxicity of amiodarone, we applied structure-activity relationship to identify DL78, which lacks hERG activity but retains the anti-cancer properties and ability to regulate Myc. DL78 is significantly more potent and tumor specific than amiodarone. It rapidly induces G2/M arrest which ultimately leads to loss of Myc, mitotic catastrophe, and apoptosis in several types of cancer cells. Furthermore, pharmacokinetics studies show that the compound is retained in the tumor upon intraperitoneal injection and has reasonable solubility and permeability, yielding good absorption, distinct from amiodarone. Given its structural and molecular differences, we expect that DL78 works through a different mechanism that amiodarone and could represent an effective treatment for ovarian cancer and other MYC-driven tumors. Additional studies will establish the foundation for further development of this novel compound, as well as reveal targeted ovarian cancer vulnerabilities.
Citation Format: Jessica McAnulty, Michele Dziubinski, Agharnan Gandhi, Margaret Farah, Pil Lee, Andrew D. White, Analisa DiFeo. Identification of a targeted anti-mitotic agent that degrades Myc and specifically induces cancer cell death [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 4003.