bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract A112: Drug discovery efforts on the RNA protein methyltransferase METTL3/METTL14
Authors: Boriack-Sjodin P. Ann , Gardino Alexandra K. , Wynn Thomas A. , Buker Shane M. , Laidlaw Monique , Sickmier E. Allen , Hodous Brian L. , Case April W. , Greene-Colozzi April E. , Copeland Robert A. , Ribich Scott
Published: March 2020

A variety of covalent modifications of and structural changes to RNA have been identified and demonstrated to affect RNA processing, stability and translation. The enzymes that catalyze these changes, RNA modifying proteins or RMPs, represent a large class of novel targets for oncology and other disease indications that can be targeted with small molecule inhibitors. Methylation of adenosine at the N6 position (m6A) in mRNA is currently the most well-studied covalent RNA modification and is catalyzed by the RNA methyltransferase enzyme complex METTL3/METTL14. Once generated, m6A can modulate mRNA splicing, export, localization, degradation and translation and is implicated in AML and multiple solid tumor indications Although potent and selective inhibitors exist for several members of the Type I S-adenosylmethionine (SAM)-dependent methyltransferase family, no inhibitors have been published for METTL3/METTL14 to date. Accent Therapeutics has prioritized drug discovery efforts on METTL3/METTL14 and potent and selective inhibitors have been identified. Enzymatic assays using multiple methodologies have been developed to facilitate inhibitor identification and characterize mechanism of inhibition for compounds; select assays are capable of measuring compounds in the picomolar range of enzyme activity. Biophysical tools have been established to validate compound binding and measure inhibitor residence time. Cellular assays that measure m6A depletion in mRNA show good correlation with biochemical assay results. Anti-proliferative activity is seen for potent compounds.

Citation Format: P. Ann Boriack-Sjodin, Alexandra K. Gardino, Thomas A. Wynn, Shane M. Buker, Monique Laidlaw, E. Allen Sickmier, Brian L. Hodous, April W. Case, April E. Greene-Colozzi, Robert A. Copeland, Scott Ribich. Drug discovery efforts on the RNA protein methyltransferase METTL3/METTL14 [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr A112. doi:10.1158/1535-7163.TARG-19-A112
Abstract A122: Molecular barcoding and single cell approaches to investigate drug tolerance in EGFRmut NSCLC
Authors: Cotton Jennifer L. , KrishnamurthyRadhakrishna Viveksagar , Chen Julie , Piquet Michelle , Wagner Joel , Boulay Gaylor , Sprouffske Kathleen , Song Youngchul , Li Xiaoyan , Schumacher Katja , Thierry Raphael , Kirkpatrick Nathaniel D. , Ruddy David A. , Korn Joshua , Morris Erick J. , Hammerman Peter S. , Engelman Jeffrey A. , Niederst Matthew J.
Published: March 2020

Patients with non-small cell lung cancer (NSCLC) that is driven by an activating mutation in the epidermal growth factor receptor (EGFR) are routinely treated with tyrosine kinase inhibitors (TKI) to specifically target the activated EGFR signaling pathway. EGFR-mutant NSCLC tumors initially respond well to EGFR inhibitors, however a subset of drug-tolerant persister cells remain at minimal residual disease (MRD) and represent a cell reservoir from which acquired genetic mutations, such as EGFRT790M or MET amplification, can emerge to render the tumor fully drug-resistant. Prior to the emergence of genetic mutations, little is known about how drug-tolerant persister cells are able to survive EGFR targeted therapy at MRD. To better understand this cell population, we investigated drug-tolerance using single cell cloning and scRNAseq in NSCLC cell lines. Using ClonTracer barcoding, we found that the same barcodes emerged after EGFR-inhibitor treatment across multiple replicates, indicating that drug-tolerance is both pre-defined and stable over many generations. Within each individual cell line, we observed multiple distinct heterogeneous subpopulations of drug-tolerant persister cells with unique gene expression signatures and proliferation rates. Additionally, we observed evidence of putative mechanisms of drug tolerance that were shared by persister cells across cells lines and used a drug combination treatment approach to target these distinct subpopulations of drug-tolerant persister cells. Taken together, our findings provide evidence that drug-tolerant persister cell subpopulations are both predefined and heterogeneous, as well as suggesting that drug-combination treatment approaches in the clinic would be more effective at targeting multiple persister cell survival mechanisms.

Citation Format: Jennifer L. Cotton, Viveksagar KrishnamurthyRadhakrishna, Julie Chen, Michelle Piquet, Joel Wagner, Gaylor Boulay, Kathleen Sprouffske, Youngchul Song, Xiaoyan Li, Katja Schumacher, Raphael Thierry, Nathaniel D. Kirkpatrick, David A. Ruddy, Joshua Korn, Erick J. Morris, Peter S. Hammerman, Jeffrey A. Engelman, Matthew J. Niederst. Molecular barcoding and single cell approaches to investigate drug tolerance in EGFRmut NSCLC [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr A122. doi:10.1158/1535-7163.TARG-19-A122
Abstract A134: Therapeutic targeting of Hdm2/HdmX E3 ligase with bioactive cyclotides
Authors: Camarero Julio A
Published: March 2020

Reactivation of tumor-suppressor p53 for targeted cancer therapy is an attractive strategy for cancers bearing wild-type (WT) p53. Targeting the Hdm2-p53 interface or HdmX-p53 interface or both has been a focus in the field. However, targeting the E3 ligase activity of Hdm2–HdmX which is mediated by RING–RING interaction has recently appeared as a promising novel anticancer approach. Targeting the E3 ligase of Hdm2-HdmX should overcome HdmX-driven resistance, which is found in many cancers overexpressing HdmX, to p53-Hdm2 antagonists such a nutlins. Cyclotides are a novel class of micro-proteins (≈30-40 residues long) with a unique topology containing a head-to-tail cyclized backbone structure further stabilized by three disulfide bonds that form a cystine knot. This unique molecular framework makes them exceptionally stable to physical, chemical, and biological degradation compared to linear peptides of similar size. The cyclotides are also highly tolerant to sequence variability, aside from the conserved residues forming the cystine knot, orally bioavailable and able to cross cellular membranes to modulate intracellular protein-protein interactions (PPIs) both in vitro and in vivo. These unique properties make them ideal scaffolds for many biotechnological applications, including drug discovery. We report the discovery of a novel cyclotide, MCo-52-2, able to antagonize efficiently the interaction between the RING domains of Hdm2 and HdmX and show p53-specific anticancer activity in several cancer cell lines both in vitro and in vivo. We will also present different strategies to improve the cellular uptake and pharmacokinetic profiles of bioactive cyclotides.

Citation Format: Julio A Camarero. Therapeutic targeting of Hdm2/HdmX E3 ligase with bioactive cyclotides [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr A134. doi:10.1158/1535-7163.TARG-19-A134
Abstract A136: Small molecule covalent drug discovery by IMTACTM
Authors: Ha Heather , Stanley Robert , Cai Qian , Zhou Wendy , Chen Hang , Yuan Irene , Cao Ping
Published: March 2020

There is currently a resurgence of interest in developing covalent drugs due to the high potency, good selectivity, and prolonged effects which may results in less-frequent drug dosing and wider therapeutic windows for patients. BridGene Biosciences established a novel IMTACTM (Isobaric Mass Tagged Affinity Characterization) platform for covalent drug discovery. Using IMTACTM platform, an intelligently designed drug-like probe with alkyne tag is able to “fish out” and identify proteins covalently bound to probes from live cells which enables us to discover druggable opportunities across the entire proteome. There are several advantages of IMTACTM : 1. Discover ligands for unliganded or undruggable targets; 2. Reduce the time and cost of lead discovery; 3. Identify additional targets of drugs or clinical candidates; 4. Build ligand-target interaction database and guide drug design. Using IMTACTM platform, our covalent library is screened in various live cells including cancer immune, and neuronal cell lines. The hit rate of IMTAC screening is about 20%, and the targets discovered by IMTACTM includes GMPS, Rictor, BTK, FABP5, ALDH, FUS, MIF and etc. Given the drug-like probe design, the probes can have nanomolar potency on the targets. And the drug like probe design minimizes the SAR efforts of developing a hit to a drug. IMTACTM platform allows us to expand the therapeutic applications of small molecule drugs to a new horizon.

Citation Format: Heather Ha, Robert Stanley, Qian Cai, Wendy Zhou, Hang Chen, Irene Yuan, Ping Cao. Small molecule covalent drug discovery by IMTACTM [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr A136. doi:10.1158/1535-7163.TARG-19-A136
Abstract B003: Combinatorial therapies of neratinib for HER2-amplified cancer
Authors: Zhao Ming , Scott Stephen , Evans Kurt , Yuca Erkan , Saridogan Turcin , Demirhan Mehmet E , Kirby Bryce P , Kopetz Scott , Diala Irmina , Lalani Alshad S , Piha-Paul Sarina A , Meric-Bernstam Funda
Published: March 2020

Activation of HER2 signaling by amplification or overexpression of ERBB2 (HER2) is associated with the development and progression of breast cancer. Neratinib is an irreversible, pan-HER tyrosine kinase inhibitor which selectively inhibits EGFR, HER2 and HER4. In this preclinical study, we explored the therapeutic efficacy of neratinib in combination with other clinically relevant targeted agents for HER2-amplified breast cancer in in vitro and in vivo models. HER2-amplified cell lines BT-474, SK-BR-3, and HCC-1954 were sensitive to neratinib with low nanomolar IC50s. Cell viability and colony formation assays demonstrated synergistic anti-proliferative activity of neratinib in combination with multiple targeted agents, including the MEK inhibitor trametinib, the PI3Ka inhibitor alpelisib, the mTOR inhibitors everolimus and sapanisertib, and CDK4/6 inhibitor palbociclib. We tested combinatorial efficacy of neratinib with everolimus, trametinib, and palbociclib in vivo on five HER2-amplified PDXs (two breast, two colorectal and one gastric-esophageal junction cancer), four derived from patients with previous HER2-targeted therapy. The combination of neratinib with everolimus or trametinib led to at least a 100% increase in median time for tumor doubling in 25% (1 of 4) and 60% (3 of 5) models respectively and was associated with decreased tumor volumes in 50% (2 of 4) and 20% (1 of 5) of the models respectively. The combination of neratinib with palbociclib significantly enhanced antitumor efficacy compared to single agent treatment in all five PDX models. The combination achieved treatment/control volume ratios of 0.03-0.16 and increased time for tumor doubling more than 100% in all five models. Taken together, our results provide solid preclinical evidence for targeting combinatorial therapies of neratinib for HER2-amplified cancer.

Citation Format: Ming Zhao, Stephen Scott, Kurt Evans, Erkan Yuca, Turcin Saridogan, Mehmet E Demirhan, Bryce P Kirby, Scott Kopetz, Irmina Diala, Alshad S Lalani, Sarina A Piha-Paul, Funda Meric-Bernstam. Combinatorial therapies of neratinib for HER2-amplified cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr B003. doi:10.1158/1535-7163.TARG-19-B003
Abstract B016: CDK7 inhibition suppresses AR addicted Castration-Resistant Prostate Cancer through MED1 inactivation
Authors: Rasool Reyaz , Natesan Ramakrishnan , deng qu , Aras Shweta , Lal Priti , Posimo Jessica , Palanisamy Nallasivam , Narla Goutham , Den Robert , Freedman Matthew , brady donita , asangani irfan a
Published: March 2020

Metastatic castration-resistant prostate cancer (CRPC) is an aggressive disease with high mortality rate, primarily resulting from the transcriptional addiction driven by Androgen Receptor (AR). First-line CRPC treatments typically target AR-signaling, but are rapidly bypassed, resulting in only a modest survival benefit with the FDA approved anti-androgen therapies such abiraterone or enzalutamide. Therefore, molecular approaches that more effectively block the AR-transcriptional program are urgently needed. Here, we present evidence demonstrating that AR transcriptional signaling is activated through a “phosphoswitch” catalyzed by cyclin-dependent-kinase 7 (CDK7). Specifically, CDK7 phosphorylates (in vitro and in vivo) the transcriptional co-activator MED1, a key subunit of Mediator complex, at Threonine 1457 to promote the formation of the AR-transcriptional complex at enhancers and super-enhancer (SE) sites. Furthermore, knockdown or inhibition of CDK7 with the recently developed covalent inhibitor THZ1 abolished T1457 phosphorylation that led to MED1 decruitment from the chromatin, attenuated AR-signaling and eliminated AR-addicted naïve or enzalutamide refractory prostate cancer cells. Interestingly, the reduced AR transcriptional output and cellular phenotypes associated with CDK7 knockdown or inhibition was reversed by T1457D phosphomimic suggesting MED1 as a major effector substrate of CDK7 transcription kinase. Finally, THZ1 demonstrated tumor regression in CRPC xenograft models in vivo. In summary, our identification of MED1 T1457 as a novel CDK7 substrate, which is essential for driving AR-mediated transcription, makes CDK7 a potential “non-oncogene dependency” in AR addicted advanced prostate cancer. Taken together, we will present data that strongly support the clinical evaluation of CDK7 specific inhibitors as a monotherapy or in combination with second generation anti-androgens in refractory castration-resistant prostate cancer. Conflict of Interest: None (P.S. This work is undergoing final revision for publication in Cancer Discovery)

Citation Format: Reyaz Rasool, Ramakrishnan Natesan, qu deng, Shweta Aras, Priti Lal, Jessica Posimo, Nallasivam Palanisamy, Goutham Narla, Robert Den, Matthew Freedman, donita brady, irfan a asangani. CDK7 inhibition suppresses AR addicted Castration-Resistant Prostate Cancer through MED1 inactivation [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr B016. doi:10.1158/1535-7163.TARG-19-B016
Abstract B052: ATR inhibition potentiates ionizing radiation-induced innate immune response via sensing cytosolic RNAs
Authors: Chen Junjie
Published: March 2020

Radiation therapy, widely used for cancer treatment for decades, is being revitalized through its ability to induce systemic anti-tumor immune response via activating type I interferon signaling, especially when it is combined with immune checkpoint blockade therapy. Mechanistic understanding of how ionizing radiation induces type I interferon signaling and how to amplify this signaling module will be highly instructive in maximizing the efficacy of radiation therapy. Here we found that ATR inhibitors, which are currently being developed as anti-cancer agents, significantly potentiate ionizing radiation-induced antiviral innate immune response. Using a series of knockout cell lines we generated for components involved in cytosolic nucleic acid sensing pathways, we demonstrated that the MAVS-dependent cytosolic RNA sensing pathway is the major pathway responsible for ionizing radiation alone or radiation plus ATR inhibitor-induced type I interferon signaling in human cells. Mechanistically, ATR-CHK1-CDC25C axis dependent G2/M DNA damage checkpoint abrogation is required for ATR inhibitor plus ionizing radiation-induced type I interferon signaling. More importantly, we proposed DNA damage-elicited double stranded DNA breaks could release AT-rich DNA sequences, which initiate MAVS-dependent type I interferon signaling via RNA polymerase III-mediated transcription in human cells. Our studies suggest that ATR inhibition in combination with radiation therapy and immune checkpoint blockade is a promising new combination therapy for cancer treatment.

Citation Format: Junjie Chen. ATR inhibition potentiates ionizing radiation-induced innate immune response via sensing cytosolic RNAs [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr B052. doi:10.1158/1535-7163.TARG-19-B052
Abstract B069: Cell Model Passports—a hub for clinical, genetic and functional datasets of preclinical cancer models
Authors: Meer Dieudonne van der , Barthorpe Syd , Yang Wanjuan , Lightfoot Howard , Hall Caitlin , Gilbert James , Francies Hayley , Garnett Mathew
Published: March 2020

In vitro cancer cell cultures are facile experimental models used widely for research and drug development. Many cancer cell lines are available and efforts are ongoing to derive new models representing the histopathological and molecular diversity of tumours. Cell models have been generated by multiple laboratories over decades and consequently their annotation is incomplete and inconsistent. Furthermore, the relationships between many patient-matched and derivative cell lines have been lost, and accessing information and datasets is time-consuming and difficult. Here, we describe the Cell Model Passports database (cellmodelpassports.sanger.ac.uk) which provides details of cell model relationships, patient and clinical information, as well as access to associated genetic and functional datasets. The Passports database currently contains curated details and standardized annotation for >1600 cell models, including cancer organoid cultures. The Passports will be updated with newly derived cell models and datasets as they are generated. Users can navigate the database via tissue, cancer-type, genetic feature and data availability to select a model most suitable for specific applications. A flexible REST-API provides programmatic data access and exploration. The Cell Model Passports are a valuable tool enabling access to high-dimensional genomic and phenotypic cancer cell model datasets empowering diverse research applications.

Citation Format: Dieudonne van der Meer, Syd Barthorpe, Wanjuan Yang, Howard Lightfoot, Caitlin Hall, James Gilbert, Hayley Francies, Mathew Garnett. Cell Model Passports—a hub for clinical, genetic and functional datasets of preclinical cancer models [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr B069. doi:10.1158/1535-7163.TARG-19-B069
Abstract B084: PLOD2 is essential to functional activation of integrin beta1 for invasion/metastasis of cancer
Authors: Kondo Eisaku , Saito Ken
Published: March 2020

Identifying the specific functional regulator of integrin family molecules in cancer cells is critical because they are directly involved in tumor invasion and metastasis. Here we report high expression of PLOD2 in various cancer cells, and its critical role as a stabilizer of ITGB1, enabling ITGB1 to initiate tumor invasion/metastasis, which was demonstrated mainly using SCC cells as a representative example. ITGB1 stabilized by PLOD2-mediated hydroxylation was recruited to the plasma membrane, its functional site, and accelerated tumor cell motility, leading to tumor metastasis in vivo, whereas loss of PLOD2 expression abrogated it. In accordance with molecular analysis, examination of SCC tissues from patients corroborated PLOD2 expression associated with ITGB1 at the invasive front of tumor nests. PLOD2 is thus implicated as the key regulator of ITGB1 that prominently regulates tumor invasion and metastasis not only in SCCs but tumors of diverse origins, and it provides important clues engendering novel therapeutics for these intractable cancers.

Citation Format: Eisaku Kondo, Ken Saito. PLOD2 is essential to functional activation of integrin beta1 for invasion/metastasis of cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr B084. doi:10.1158/1535-7163.TARG-19-B084
Abstract B097: Development of a mouse-human chimeric antibody against human CXADR having a potent antitumor activity in animal models
Authors: Kawada Manabu , Sakamoto Shuichi , Inoue Hiroyuki , Kaneko Mika , Ogasawara Satoshi , Kajikawa Masunori , Urano Sakiko , Ohba Shun-ichi , Kato Yukinari
Published: March 2020

Coxsackievirus and adenovirus receptor (CXADR) is a single-pass transmembrane protein that is expressed on some cancers including prostate, lung, and brain tumor tissues. We previously developed a mouse monoclonal antibody against human CXADR, mu6G10A, and found that mu6G10A significantly exerts an anti-tumor activity against various human cancer cell lines expressing CXADR through antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) activities. In this study, we have developed a mouse-human chimeric anti-CXADR antibody, ch6G10A, from mu6G10A, and evaluated its anti-tumor activity. As a result, in vitro experiments clearly showed that ch6G10A possesses binding, ADCC, and CDC activities against human prostate cancer DU-145 cells expressing CXADR like mu6G10A. In vivo xenograft models showed that ch6G10A exerts a significant anti-tumor activity against DU-145 cells when human NK cells were co-injected. These results indicate that a mouse-human chimeric anti-CXADR antibody, ch6G10A, has a therapeutic potential as a novel anti-tumor antibody drug.

Citation Format: Manabu Kawada, Shuichi Sakamoto, Hiroyuki Inoue, Mika Kaneko, Satoshi Ogasawara, Masunori Kajikawa, Sakiko Urano, Shun-ichi Ohba, Yukinari Kato. Development of a mouse-human chimeric antibody against human CXADR having a potent antitumor activity in animal models [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr B097. doi:10.1158/1535-7163.TARG-19-B097
Abstract B122: The CD98hc oncoprotein as a target of new anticancer therapy
Authors: Lanzillotta Delia , Iaccino Enrico , Artese Anna , Mimmi Selena , D'Agostino Sabrina , Romeo Isabella , Cantafio Patrizia , Dattilo Vincenzo , Costa Giosuè , Brescia Carolina , Gaudio Eugenio , Alcaro Stefano , Trapasso Francesco
Published: March 2020

Among the proteins putatively interacting with PTPRJ, a tyrosine phosphatase with tumor suppressor activity, we focused on the oncoprotein CD98hc as a very interesting candidate for the development of innovative targeted drugs. In fact, CD98hc, representing the heavy chain of a transmembrane aminoacid transporter, is overexpressed in several human cancers. Furthermore, CD98hc higher expression is associated with poor prognosis in lung cancer patients. CD98hc is linked to light chains (LATs, xCT) by disulfide bridge, polar and hydrophobic interactions. The light chain confers substrate specificity, and ERK, AKT, FAK and mTOR pathways are involved in CD98hc-LATs/xCT downstream signals. Moreover, CD98hc is a coreceptor of b-integrins and it is involved in cell proliferation, migration and invasion. We identified two peptides and 15 small molecules (putatively targeting the disulfide bridge) as candidate CD98hc inhibitors by phage display and in silico screenings, respectively, and validated in vitro the binding between peptides and transmembrane fraction of CD98hc by cytofluorimetric assay. Then, we tested the capability of both types of compounds to affect cell viability and proliferation through MTT and CFSE assays, respectively. We observed that the targeting of CD98hc through both peptides and small molecules reduced cell proliferation in A549 human lung cancer cells, strongly encouraging a deeper characterization of these candidate anticancer molecules. Indeed, our next goals will be the assessment of biochemical activity of CD98hc following to its inhibition, as well as the evaluation of compounds toxicity, both in vitro and in vivo. The final aim is to identify lead compounds inhibiting CD98hc, in order to develop novel molecules to be translated in the clinical setting and to be used as monotherapy and/or in a combinatorial approaches for the treatment of cancer patients.

Citation Format: Delia Lanzillotta, Enrico Iaccino, Anna Artese, Selena Mimmi, Sabrina D'Agostino, Isabella Romeo, Patrizia Cantafio, Vincenzo Dattilo, Giosuè Costa, Carolina Brescia, Eugenio Gaudio, Stefano Alcaro, Francesco Trapasso. The CD98hc oncoprotein as a target of new anticancer therapy [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr B122. doi:10.1158/1535-7163.TARG-19-B122
Abstract C014: Development of an injectable water-soluble anticancer drug CMG for oxaliplatin-resistant colorectal cancer with KRAS mutation
Authors: Kakeya Hideaki , Kishimoto Atsuhiro , Umeta Hitomi , Imaizumi Atsushi , Kanai Masashi
Published: March 2020

Recent well-designed preclinical studies have demonstrated that KRAS mutations can activate the canonical NF-κB signaling pathway, which is a pivotal role in tumor progression. Therefore, inhibition of this KRAS-NF-κB axis would be a promising target to develop a new molecular targeted anticancer agent. Curcumin, a naturally occurring polyphenol derived from the plant Curcuma longa, has been shown to block NF-κB signaling pathway via at least two mechanisms; inhibition of IkB phosphorylation and inhibition of ubiquitin-dependent degradation of IκB. Recently dual-specificity tyrosine-regulated kinase (DYRK2), a positive regulator of the 26S proteasome, has been reported as a direct molecular target of curcumin, which is consisted with the inhibition of NF-κB signaling pathway by curcumin. Several preclinical studies have clearly demonstrated that curcumin exhibits anticancer effects in colorectal cancer model through NF-κB inhibition. However, since curcumin is highly lipophilic and orally administrated curcumin has very low bioavailability, its clinical application in cancer patients has been hampered. Very recently we developed a synthetic water-soluble prodrug CMG, curcumin mono-β-D-glucuronide, to overcome these problems. In this study, we investigated the anticancer effect of CMG on oxaliplatin (L-OHP) -resistant colorectal cancer cells HCT116 with KRAS mutation and p53 deletion (KRAS+p53- cells). Curcumin, the active substance released from CMG in vivo, showed similar effects regardless of KRAS/p53 mutation status in vitro. In xenograft models using KRAS+p53- HCT116 cells, intraperitoneal administration of CMG significantly superior antitumor effects compared to L-OHP monotherapy. Notably, no adverse events were noted in the CMG group, whereas bodyweight loss, severe myelosuppression, and liver damage were observed in the L-OHP group. Combination of CMG and L-OHP showed additive antitumor effects with moderate suppression of liver damage by L-OHP. These results indicate that CMG could be a novel anticancer drug with minimal toxicities for colon cancer patients with KRAS and p53 mutations.

Citation Format: Hideaki Kakeya, Atsuhiro Kishimoto, Hitomi Umeta, Atsushi Imaizumi, Masashi Kanai. Development of an injectable water-soluble anticancer drug CMG for oxaliplatin-resistant colorectal cancer with KRAS mutation [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr C014. doi:10.1158/1535-7163.TARG-19-C014
Abstract C053: NP-G2-044, a novel fascin inhibitor, blocks tumor metastasis and increases antitumor immune response
Authors: Chung Vincent , Tsai Frank , Jhaveri Komal , Wang Yufeng , Hoff Daniel D Von , Garmey Edward G , Zhang J. Jillian , Huang Xin-Yun
Published: March 2020

Filopodia are finger-like plasma membrane protrusions that are formed upon remodeling of the actin cytoskeleton beneath the plasma membrane. Fascin protein is the main actin-bundling protein in filopodia and invadopodia which are fundamental to cell shape and motility events. Human fascin expression is low or absent in normal adult epithelial cells but highly expressed in metastatic tumors and in antigen-presenting dendritic cells within the tumor microenvironment. Elevated levels of fascin are correlated with poor prognosis and short survival due to aggressive phenotypes with increased lymph node and distant metastases. Mouse genetic studies demonstrate that deletion of fascin gene delays tumor development, slows tumor growth, reduces metastatic colonization, and increases overall survival. These mouse genetic studies provide strong evidence for fascin’s role in tumor initiation, tumor progression and tumor metastasis, making it an attractive target for drug development. Chemical libraries were screened to identify small-molecule compounds that specifically inhibit the biochemical function of fascin to bundle actin filaments. The inhibitors were optimized to produce the lead compound, NP-G2-044. Preclinical studies showed that fascin inhibitors increase the overall survival of tumor-bearing mice and reinvigorate anti-tumor immune response in syngeneic mouse models of breast, lung, pancreatic and prostate tumors. Fascin protein levels are increased in conventional dendritic cells (cDCs) in the immunosuppressive tumor microenvironment. The number of intra-tumoral activated cDCs is increased following fascin inhibitor treatment. Moreover, together with anti-PD-1 antibody, fascin inhibition markedly increases the number of Ki67+ proliferating and Granzyme-B+ activated CD8+ killer T-cells in tumor tissue. These data demonstrate that fascin inhibitors simultaneously act on tumor cells to block tumor metastasis and on intratumoral DCs to reinvigorate anti-tumor immune response. We are currently conducting a first-in-human phase 1 trial of NP-G2-044 in patients with advanced or metastatic solid tumor malignancies.

Citation Format: Vincent Chung, Frank Tsai, Komal Jhaveri, Yufeng Wang, Daniel D Von Hoff, Edward G Garmey, J. Jillian Zhang, Xin-Yun Huang. NP-G2-044, a novel fascin inhibitor, blocks tumor metastasis and increases antitumor immune response [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr C053. doi:10.1158/1535-7163.TARG-19-C053
Abstract C089: Adaptive responses of low-grade ovarian cancer cell lines to MEK inhibitor
Authors: Wong Kwong-Kwok , Tsang Yvonne T , Chen Michelle , Kun Eucharist H , Gershenson David M
Published: March 2020

Low-grade ovarian serous carcinomas (OSC) account for more than 70% epithelial ovarian cancers in young women. The exact biological pathways that underlie this disease are elusive. Moreover, chemotherapy and hormonal therapy are relatively ineffective and have generally failed to reduce the high morbidity and mortality associated with this disease. Because the Ras/Raf/MEK/ERK pathway is frequently activated in low-grade OSC, targeting this pathway has been examined as a potential avenue for treatment. Results from a phase II Gynecologic Oncology Group (GOG) trial for patients with recurrent low-grade OSC indicated a majority of the patients had developed resistance to Selumetinib (a MEK inhibitor). There were one complete responder, seven partial responders and 34 patients with stable disease out of the 52 patients treated with the MEK inhibitor. In order to understand the MEK inhibitor adaptive response, we have generated two MEK inhibitor (MEKi) adaptive resistant low-grade OSC cell lines. Using functional proteomic analysis by reverse phase protein array (RPPA), we identified several signaling pathways affected by MEKi (trametinib). Our data indicated pAKT was the most up-regulated protein by MEKi. In addition, other proteins in the mTOR, NF-kB, RTK and immune suppressive pathways were up-regulated. We further validated the result by western blot analysis, phospho-ERK, CHK1, MSH2, pRB and DUSP6 were down-regulated, while pAKT, B7-H4, BIM, and p27 were significantly up-regulated. More interestingly, SERPINE1 was the only highly expressed protein in both MEKi adaptive resistance low-grade OSC cell lines, and its expression was not affected by MEKi treatment. Knocking down the expression of SERPINE1 by siRNA targeting SERPINE1 in the MEKi-resistant low-grade OSC cell line was able to attenuate its resistance to trametinib. In summary, we have deciphered several adaptive responses of low-grade ovarian cancer cell lines to MEK inhibitor and the up-regulation of the SERPINE1 pathway is partly responsible for the development of adaptive resistance.

Citation Format: Kwong-Kwok Wong, Yvonne T Tsang, Michelle Chen, Eucharist H Kun, David M Gershenson. Adaptive responses of low-grade ovarian cancer cell lines to MEK inhibitor [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr C089. doi:10.1158/1535-7163.TARG-19-C089
Abstract C090: Systematic review of neurotrophic tyrosine receptor kinase inhibition as a tumor-agnostic management strategy
Authors: Chu Paula , Batson Sarah , Mitchell Catherine , Hodgson Matt
Published: March 2020

NTRK mutations occur in up to 1% of all solid tumours and are observed in more than 20 different malignancies over diverse tissue/cell lineages. The potential clinical effectiveness of TRK inhibitors is being assessed in phase I and II trials. A systematic review was conducted to provide a summary of published evidence for the currently available NTRK-targeted agents; a meta-analysis feasibility was also conducted to assess whether quantitative comparisons could be made on their relative efficacy and safety. The electronic databases Medline®, Medline® Epub Ahead of Print (In-Process & Other Non-Indexed Citations), Embase, and EBM Reviews were interrogated. Eligibility criteria included clinical studies, economic evaluations, utility studies, or cost/resource use studies conducted in patients (adults or paediatric patients) with NTRK+ solid tumours. 27 publications reported clinical data for seven interventions. Efficacy/safety data were available for two interventions only. Data from a pooled analysis of three trials reported an objective response rate (ORR) for larotrectinib of 75% (95% confidence interval [CI] 61–85). After one year, 71% of responses were ongoing, 55% of patients remained progression free, and 90% of patients were still alive. An integrated analysis of entrectinib-treated patients reported an ORR of 57.4% (95% CI 43.2–70.8) and a complete response in 4 patients (7.4%). The median duration of response was 10.4 months (95% CI 7.1– not reported [NR]), median overall survival was 20.9 months (95% CI 14.9–NR) and progression-free survival was 11.2 months (95% CI 8.0–14.9). Both larotrectinib and entrectinib were well tolerated with the majority of adverse events being grade 1 or 2. No relevant economic or humanistic studies were identified. A meta-analysis feasibility assessment was conducted to compare the relative efficacy of entrectinib and larotrectinib for outcomes of interest. However, a robust meta-analysis was not feasible due to the single-arm design of eligible studies, heterogeneity of patient population and outcome data, and small sample sizes. Available evidence to date demonstrates that the currently available NTRK-targeted agents are generally well tolerated and are associated with an impressive clinical benefit (as assessed by ORR). Further corroboration from the expansion of existing studies and real-world data would strengthen the evidence base and further elucidate the optimum positioning of NTRK-targeted agents in the treatment pathway.

Citation Format: Paula Chu, Sarah Batson, Catherine Mitchell, Matt Hodgson. Systematic review of neurotrophic tyrosine receptor kinase inhibition as a tumor-agnostic management strategy [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr C090. doi:10.1158/1535-7163.TARG-19-C090
Abstract C120: The tumor suppressor role of STXBP6 in triple negative breast cancer
Authors: Lenka Govinda , Shan Jingxuan , Abuaqel Sirin , Chouchane Lotfi
Published: March 2020

Triple negative breast cancer (TNBC) is a subtype of breast cancer (BC) that accounts for approximately 15–20% of all BCs. Additionally, TNBC presents with a poor prognosis mainly due to the lack of effective therapeutic options. For this reason, numerous studies have focused to find the potential molecular targets. Syntaxin binding protein 6, encoded by STXBP6, was initially identified in regulating the formation of the SNARE complex and cytogenesis. It has been reported to be associated with many diseases, such as diabetes, autism and systemic lupus erythematosus. However, there are no studies revealing its biological role and its epigenetic regulation in TNBC. Thus, herein we aim to demonstrate antitumor implications of STXBP6 in TNBC. In this study first, we explored the clinical significance of STXBP6 in cancer. Pan-cancer profiling using TCGA data sets identified aberrant expression of STXBP6 in different cancer types. Importantly, we identified significant down regulation of STXBP6 in TNBC samples. Moreover, significantly improved survival rates were observed in patients when STXBP6 expression levels high. The concurrent analysis between gene expression and methylation of STXBP6 highlighted a clear negative correlation. When the luminal subtype and TNBC subtype of BC cells were treated with demethylating agent 5-aza-2’-deoxycytidine, we observed an increase in the expression of STXBP6 in TNBC cells only which further support the regulatory role of DNA methylation in the control of STXBP6 expression in TNBC. Next, we elucidated the function of STXBP6 in TNBC cells. Overexpression of STXBP6 in TNBC cells significantly decreased cell proliferation, colony formation and increased apoptosis. In summary, these findings highlight the suppression effect of STXBP6 on TNBC progression and could be a novel prognostic and therapeutic target for TNBC in the future. Key Words: STXBP6, Gene Expression, Methylation, Tumor Suppressor, Triple Negative Breast Cancer.

Citation Format: Govinda Lenka, Jingxuan Shan, Sirin Abuaqel, Lotfi Chouchane. The tumor suppressor role of STXBP6 in triple negative breast cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr C120. doi:10.1158/1535-7163.TARG-19-C120
Abstract C124: HIF-independent synthetic lethality between CDK4/6 inhibition and VHL loss across species
Authors: Nicholson Hilary , Housden Benjamin , Perrimon Norbert , Kaelin William G
Published: March 2020

Inactivation of the von Hippel-Lindau (VHL) tumor suppressor gene and its protein product, pVHL, occurs in ~90% of clear cell renal cell carcinoma (ccRCC) cases. pVHL is part of the ubiquitin ligase complex that targets the HIF2α transcription factor, an oncoprotein in ccRCC, for proteasomal degradation. Without functional pVHL, HIF2α accumulates and induces inappropriate transcription of angiogenic, invasive, and growth-promoting genes. Drugs inhibiting HIF2α or its downstream target VEGF are active against ccRCC, but both de novo and acquired resistance are common and no current therapies are curative. We hypothesized that loss of pVHL might create context-specific dependencies that could then be targeted therapeutically. To look for such synthetic lethal targets, we generated human and Drosophila cell pairs that were isogenic for pVHL (or its Drosophila ortholog) and screened using RNAi and chemical compound libraries. The overlap of the hits from these screens identified a hyperdependence on CDK4/6 activity in pVHL-defective cells compared to their pVHL-proficient counterparts. In secondary assays we confirmed that pharmacologic inhibition of CDK4/6 by either Abemaciclib or Palbociclib preferentially reduced viability of VHL-/-cells as compared to VHL+/+cells across a variety of human ccRCC cell lines. Importantly, inhibition of VHL-/-ccRCC cells by Palbociclib was abrogated by expressing a Palbociclib-resistant CDK6 cDNA or by knockout of the canonical CDK4/6 target pRB. Sensitivity to Palbociclib could be reversed by expressing exogenous pVHL, but not a pVHL mutant lacking its known substrate docking site. HIF2aknockout in VHL-/-cells did not eliminate the effect of CDK4/6 inhibition, thus HIF2ais not necessary for the synthetic lethal relationship between VHLand CDK4/6. Moreover, the combination of the HIF2ainhibitor PT2399 and the CDK4/6 inhibitor Palbociclib synergistically suppressed proliferation of VHL-/-ccRCC in vitro in HIF2a-sensitive cell lines. Both Palbociclib and Abemaciclib suppress VHL-/-ccRCC tumor growth in nude mice, including tumors that are PT2399-resistant. My future work will aim to identify the mechanism that underlies the synthetic lethality between VHLand CDK4/6 activity.

Citation Format: Hilary Nicholson, Benjamin Housden, Norbert Perrimon, William G Kaelin. HIF-independent synthetic lethality between CDK4/6 inhibition and VHL loss across species [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr C124. doi:10.1158/1535-7163.TARG-19-C124
Abstract CN03-01: Functional genomics approaches to the discovery of paralog dependencies in cancer
Authors: Sellers William
Published: March 2020

Advances in next-generation sequencing and projects including the Cancer Genome Anatomy project and the International Cancer Genome Consortium have given us a detailed description of the genetic alterations across a broad spectrum of cancer. This however, does not immediately lead to a detailed functional understanding of those genes whose protein products are necessary for the maintenance of cancer viability. In order to more deeply understand the genes and pathways critical to the survival of cancer cells previous and ongoing efforts have provided functional annotation of the Cancer Cell Line Encyclopedia through the use of deep pooled shRNA or sgRNA libraries. For example, Project DRIVE (Deep RNAi-screening for Viablity Effects in cancer) characterized the viability effects of knockdown of 7,837 genes using 20 shRNAs per gene across 398 cancer cell lines. The DepMap project targeted 18,333 genes in 625 cell lines using CRISPR/CAS9. The data from these efforts are highly robust identifying all known oncogenes mutated in the set of interrogated cell lines, along with multiple new cancer dependent features not previously described. Notably, very few synthetic lethal nodes have emerged from these analyses downstream or within the critical oncogenic pathways that dominate the landscape of human cancer. We hypothesize that this is due to functionally redundant paralogous genes that, while potentially targetable by single therapeutics, are not targeted in current knockdown/knockout screens. This is exemplified by discordance between certain therapeutics and shRNA or sgRNA gene inactivation. For example, the cell line sensitivity profiles of MEK inhibitors which target MEK1 and MEK2, or CDK4/6 inhibitors do not robustly correlate with single gene knockout data. Based on prior work using dual S. pyogenes and S. aureus CAS9 systems, we have built a pairwise sgRNA library targeting roughly 3000 genes and the resulting 5,000 paralog pairs. Initial screening data has demonstrated robustness of the methods. More importantly, new paralog dependencies relevant to NRAS mutant cancers have emerged.

Citation Format: William Sellers. Functional genomics approaches to the discovery of paralog dependencies in cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr CN03-01. doi:10.1158/1535-7163.TARG-19-CN03-01
Abstract CN03-02: Functional genomics approaches to identify targetable dependencies in cancer cells
Authors: Garnett Mathew
Published: March 2020

The next-generation sequencing of tumors is providing an increasingly detailed description of the molecular alterations that occur across the diversity of human cancers. An important and challenging next step is to convert this wealth of information into new therapeutic hypotheses to guide patient care. My laboratory integrates cancer genomics, experimental functional genomics and mechanistic studies to elucidate vulnerabilities operative in cancer cells. These efforts are part of our Cancer Dependency Map initiative which aims to assign a dependency to every cancer cell in a patient and which could be exploited to develop new therapies (https://depmap.sanger.ac.uk/). In my presentation, I will discuss recent results from my laboratory and how these are shaping our understanding of the landscape of targetable dependencies in cancer cells.

Citation Format: Mathew Garnett. Functional genomics approaches to identify targetable dependencies in cancer cells [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr CN03-02. doi:10.1158/1535-7163.TARG-19-CN03-02
Abstract CN08-03: LIF in cancer
Authors: Seoane Joan
Published: March 2020

The tumor microenvironment has a critical role in cancer progression. We have identified LIF as a regulator of the tumor stroma, specifically of the tumor immune response. LIF is a cytokine with a crucial role in embryogenesis and previous work has identified LIF as an oncogenic factor that regulates cancer-initiating cells, cancer-associated fibroblasts and chemo- and radioresistance. We have observed that in tumors expressing high levels of LIF, the blockade of LIF inhibited tumor growth and caused tumor regression through the engagement of an immune response. The anti-tumor effect of LIF neutralization was mediated by the tumor-associated macrophages through the regulation of a set of cytokines that impacted on the T cell response. The LIF-mediated immune suppression was observed in several tumor types with an important incidence in glioblastoma. Our results identify LIF as a critical cytokine in the immune response to cancer and a promising therapeutic target.

Citation Format: Joan Seoane. LIF in cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr CN08-03. doi:10.1158/1535-7163.TARG-19-CN08-03