bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract B061: A novel cell-mediated immunotherapy for treatment of lung and breast cancer
Authors: Venugopal Indu , Gormley Claire , McGuire Michael J , Brown Kathlynn C
Published: March 2020

Cancer Immunotherapies designed to generate a cell-mediated immune response against tumors are emerging as frontline treatment options for cancer; however, concerns regarding efficacy, safety and cost efficacy have limited the use of these treatments. To address these weaknesses, we have developed a novel immunotherapy capable of delivering previously encountered antigenic peptides specifically to cancer cells and facilitating their presentation through the MHC class I pathway. Our therapy utilizes a modular synthetic nanoparticle delivery system comprising of three components: a neutral stealth liposome, encapsulated synthetic immunogenic HLA class I restricted peptides derived from measles virus (MV), and a tumor-targeting peptide on the external surface of the liposome. The targeting peptide results in accumulation of the liposomes specifically inside cancer cells and facilitates presentation of the MV-derived immunogenic peptides in HLA class I molecules. We refer to this system as TALL (Targeted Antigen Loaded Liposomes). Therefore, TALL can generate a secondary immune response specifically against the targeted tumor cells in a patient who has been previously vaccinated against or infected by MV. In short, we are attempting to trick the immune system into responding as though the cancer cell is infected with MV without the use of a viral particle. We have demonstrated that this approach leads to a cancer-specific CD8+ T cell response which requires all three components of the TALL system. The lead cancer-targeting peptide has been optimized for affinity, cellular uptake, hydrophobicity, and stability. The TALL liposomes home to tumors in vivo. We have demonstrated a significant reduction in subcutaneous tumor growth using P-TALL in aggressive LLC1 and 4T1 murine models.

Citation Format: Indu Venugopal, Claire Gormley, Michael J McGuire, Kathlynn C Brown. A novel cell-mediated immunotherapy for treatment of lung and 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 B061. doi:10.1158/1535-7163.TARG-19-B061
Abstract B063: Role of HIPEC and its association with regulatory T cells in ovarian cancer: Preliminary experience from tertiary care center in India
Authors: Ray Mukurdipi , Rizwan Arshi
Published: March 2020

Introduction: Epithelial Ovarian cancer (EOC) is the most lethal Gynaecological Cancer and incidence is rapidly increasing in India and it is a leading cause of death due to its high relapse rate. Despite of multimodality treatment, the 5 years survival is dismal and for last three decades it is 15-30% and recurrence rate >70%. The Hyperthermic intraperitoneal chemotherapy (HIPEC) is a highly concentrated, heated chemotherapy, delivered directly to the abdominal cavity at the end of complete Cytoreduction surgery aiming to destroy the microscopic cancer cells. Experimental Procedure: Regulatory T cells (Tregs) play a crucial role in ovarian cancer suppression and its recurrence. However changes in Tregs population in patients with ovarian cancer after HIPEC in not yet known. On occurrence of cancer, immunological imbalance between Tregs and Th17 cells leads to cancer suppression or inflammation. Our study aims to understand the expression pattern of Tregs (CD4+,CD25+, CD127- ,IL10+,Foxp3+) and Th17(CD4+, CCR6+, IL17+, RORγ) and intracellular cytokine profile in peripheral blood by flow cytometry before and after the HIPEC in 1st week and 4th week. Summary: We have observed that percentage of Tregs in Ovarian Cancer patients (n=24) were high as compared to healthy controls before HIPEC and were reduced remarkably after 4 weeks of operation. Th17 cells frequency was low before HIPEC but in patients with good recovery Th17 cells are relatively high after 4 weeks of HIPEC. The percentage of Tregs was very high in stage III/IV before HIPEC treatment whereas there is some change in Th17 cells observed before and after HIPEC. This is a preliminary data results will be further confirmed by having more number of patients and after statistical analysis. Further we are also looking forFOXP3expressionat tissue and gene level by Immunohistochemistry (IHC) and real time PCR to compare the difference in expression of FOXP3 Conclusion: Our work raises the possibility that the HIPEC procedure not only kills tumour cells but also induces an efficient anticancer immune response, therefore opening new therapeutic windows for the patients of EOC.

Citation Format: Mukurdipi Ray, Arshi Rizwan. Role of HIPEC and its association with regulatory T cells in ovarian cancer: Preliminary experience from tertiary care center in India [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 B063. doi:10.1158/1535-7163.TARG-19-B063
Abstract B073: Development of combination therapies to potentiate the impact of KRAS-G12C inhibitors in lung cancer
Authors: Molina-Arcas Miriam , Moore Christopher , Rana Sareena , Maldegem Febe Van , Mugarza Edurne , Romero-Clavijo Pablo , Horswell Stuart , Hancock David , Downward Julian
Published: March 2020

Oncogenic mutations in KRAS are frequent in non-small cell lung cancer (NSCLC) and have been associated with poor prognosis and resistance to existing therapies. We have previously shown that NSCLC cells harboring KRAS mutations are selectively sensitive to inhibition of MEK and IGF1R signaling. Using a whole-genome shRNA screen, we shown that this effect is markedly enhanced by simultaneous inhibition of mTOR, while maintaining selectivity for the KRAS mutant genotype. Mechanistic investigations demonstrated that IGF1R inhibitors block the reactivation of the PI3K pathway induced by mTOR inhibition, resulting in a robust suppression of PI3K and mTORC1 signalling. Addition of a MEK inhibitor to the combination results in simultaneous inhibition of the main nodes downstream of RAS. Notably, the inhibition of these signalling pathways is stronger in KRAS-mutant cells than in their wild-type counterparts. Combining MEK, IGF1R and mTOR inhibitors produces a profound and durable suppression of cell proliferation and a stronger induction of apoptosis, resulting in marked tumor regression in three different Kras-driven lung cancer mouse models. In order to achieve strong downstream pathway inhibition even more specifically in KRAS-mutant cells and reduce potential unwanted toxicities, we used KRAS-G12C mutant inhibitors. We show that the triple combination of mTOR, IGF1R and KRAS-G12C inhibitors causes a profound and durable inhibition of the main pathways downstream RAS and greatly improves the effectiveness of ARS-1620 on KRAS-G12C mutant lung cancer cells in vitro and in mouse models. This provides a clear rationale for the design of combination treatments to enhance and extend the response to KRAS-G12C inhibitors.

Citation Format: Miriam Molina-Arcas, Christopher Moore, Sareena Rana, Febe Van Maldegem, Edurne Mugarza, Pablo Romero-Clavijo, Stuart Horswell, David Hancock, Julian Downward. Development of combination therapies to potentiate the impact of KRAS-G12C inhibitors in lung 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 B073. doi:10.1158/1535-7163.TARG-19-B073
Abstract B074: Sapanisertib in combination with trametinib in glioblastoma models enhances target inhibition and antitumor activity
Authors: Schreck Karisa C , Allen Amy , Wang Jiawan , Pratilas Christine A
Published: March 2020

Objective: To determine the biological and signaling effects of dual-pathway inhibition with mTORC1/2 and MEK inhibitors in glioblastoma neurosphere cell lines. Background: The PI3K/mTOR signaling pathway is frequently dysregulated in glioblastoma (GBM), making it the focus of active scientific and drug development efforts in brain tumors. Unfortunately, small molecule targeted therapies against EGFR and its downstream effector pathways, while promising in the pre-clinical setting, have been disappointing in glioma clinical trials. The mTOR pathway target ribosomal protein S6 (RPS6) can also be activated by the ERK pathway target p90-RSK. We therefore tested the hypothesis that small molecule inhibition of both ERK and mTOR signaling pathways would result in enhanced anti-tumor activity. Methods: Seven glioblastoma neurosphere lines were tested for sensitivity to the ATP-competitive mTORC1/2 inhibitor sapanisertib (MLN0128) alone or in combination with the allosteric MEK1/2 inhibitor trametinib (GSK1120212) using cell growth assays and immunoblots as indicated. Results: The dual mTORC1/2 inhibitor sapanisertib inhibits mTOR signaling and cell growth in all GBM neurosphere lines, but only partially inhibits phosphorylation of the downstream target ribosomal protein S6 (phospho-RPS6) in these models. The MEK inhibitor, trametinib, inhibited ERK phosphorylation in all neurosphere lines, though phosphorylation of downstream targets and cell growth were inhibited to varying degrees. Inhibition of RPS6 activation was dose-dependent and correlated with cell line sensitivity when treated with trametinib but not with sapanisertib. In combination, sapanisertib plus trametinib showed more profound inhibition of phospho-RPS6, as well as enhanced growth inhibition and induction of apoptosis in sensitive neurosphere lines. Conclusions: The combination of sapanisertib and trametinib may have significant antitumor activity in glioblastoma neurospheres by enhanced inhibition of S6, which serves as the convergence point between these effector pathways.

Citation Format: Karisa C Schreck, Amy Allen, Jiawan Wang, Christine A Pratilas. Sapanisertib in combination with trametinib in glioblastoma models enhances target inhibition and antitumor activity [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 B074. doi:10.1158/1535-7163.TARG-19-B074
Abstract B099: Characterization of monoclonal antibodies generated to the 287-302 amino acid loop of the human epidermal growth factor receptor
Authors: Ho Eric Chun Hei , Antignani Antonella , Sarnovsky Robert , FitzGerald David J
Published: March 2020

Dysregulation of the epidermal growth factor receptor (EGFR) has been implicated in the oncogenesis of malignancies including glioblastoma and various epithelial cancers. Oncogenesis occurs from overexpression of EGFR, often linked to gene amplification or receptor mutagenesis. The 287-302 loop from the extracellular domain is exposed completely on EGFRvIII (deletion of exons 2-7), partially exposed on some cancers but cryptic on normal cells expressing WT levels of EGFR. We report on the generation of antibodies to this loop. A peptide corresponding to amino acids 286-303 was synthesized and then coupled chemically to Keyhole Limpet Hemocyanin. After immunizations, sera were assayed for reactivity to the peptide. Mice with high titers were used for hybridoma production. Purified antibodies were isolated from hybridoma supernatants, while V-regions were cloned and sequenced. Receptor binding was characterized using ELISA and flow cytometry. Monoclonal antibodies (n=7) reactive for the 287-302 loop were characterized further. Each one reacted with EGFRvIII but not EGFR WT. Based on reactivity with the immunizing peptide, antibodies were mapped to one of three subgroups. One antibody, 40H3, also exhibited binding to MDA-468 and A431 cells but not to non-cancerous WI-38 cells. Because of its unusual binding characteristics, a recombinant immunotoxin was generated from 40H3, which proved to be potently cytotoxic for MDA-468, A431 and F98-EGFRvIII-expressing cells. We conclude that immunization with a peptide corresponding to a cryptic EGFR epitope can produce cancer-binding antibodies. By way of example, the 40H3 antibody was engineered as a cytotoxic recombinant immunotoxin and could be developed as a therapeutic agent for clinical use.

Citation Format: Eric Chun Hei Ho, Antonella Antignani, Robert Sarnovsky, David J FitzGerald. Characterization of monoclonal antibodies generated to the 287-302 amino acid loop of the human epidermal growth factor receptor [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 B099. doi:10.1158/1535-7163.TARG-19-B099
Abstract B121: An oncogene-linked prodrug strategy in lung cancer
Authors: Boudreau Aaron , Roth Jennifer , Rong James , Olsson Niclas , Mader Chris , Byran Jordan , Rossen Jordan , Wang Li , Larpenteur Kevin , Goodale Amy , Trepicchio Colin , Bender Samantha , Tsherniak Aviad , Subramanian Aravind , Kocak Mustafa , Piccioni Federica , Bittker Josh , Zhu Cong , Li Frank , Eriksson Nick , Koller Daphne , McAllister Fiona , Golub Todd , Settleman Jeff , Firestone Ari , Stokoe David
Published: March 2020

KEAP1-mutant non-small cell lung cancer is a high prevalence indication that responds poorly to conventional chemotherapy owing to constitutive activation of NRF2 and its associated drug metabolism target genes. Using an approach to identify compounds that selectively kill cancer cell lines in a biomarker-driven manner, we identify BRD-K19050021 (K1905), a compound displaying strong toxicity in cells expressing CYP4F11 - a cytochrome p450 family member and NRF2 transcriptional target. Using genome-wide pooled CRISPR screens, we show that CYP4F11 activity is necessary and sufficient for response to K1905, and in acquired resistance models developed from multiple cell lines, we show a minor subpopulation of cells mechanistically converge on suppressed CYP4F11 expression to bypass K1905 response. CYP4F11 converts K1905 from a prodrug into a covalent active metabolite that alkylates several cellular targets, triggering all three canonical arms of the unfolded protein response pathway and culminating in cell death. We propose that CYP4F11 and similar metabolic enzyme activities promoted by oncogenic drivers represent a unique opportunity to restrict prodrug activation within tumors, provided that normal tissue expression of such prodrug-converting enzymes do not diminish therapeutic index.

Citation Format: Aaron Boudreau, Jennifer Roth, James Rong, Niclas Olsson, Chris Mader, Jordan Byran, Jordan Rossen, Li Wang, Kevin Larpenteur, Amy Goodale, Colin Trepicchio, Samantha Bender, Aviad Tsherniak, Aravind Subramanian, Mustafa Kocak, Federica Piccioni, Josh Bittker, Cong Zhu, Frank Li, Nick Eriksson, Daphne Koller, Fiona McAllister, Todd Golub, Jeff Settleman, Ari Firestone, David Stokoe. An oncogene-linked prodrug strategy in lung 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 B121. doi:10.1158/1535-7163.TARG-19-B121
Abstract B123: Full-length bio-active atypical protein kinase c ι expression and purification in a bacterial system
Authors: Smalley Tracess , Patel Rekha , Acevedo-Duncan Mildred
Published: March 2020

Background: Proteins are at the steering wheel in the route of cancer progression. Protein kinase C (PKC) is a contributor to malignant advancement and it pushes past some of the normal cell’s defenses. In particular, PKC-ι participates in oncogenesis at varying levels in signaling and tissue specificity. Around 70% of the selected chemical entities that are the result of in-silico investigations are found to be rejected in the final stages of drug development. Therefore, binding studies are essential to in-silico techniques and are pivotal for finding kinase inhibitors for overly active proteins like PKC-ι. Despite the fact that there are numerous binding studies involving PKC-ι, protein production remains tedious and expensive. Objective: In this investigation, we hope to produce large amounts of recombinant bio-active full-length PKC-ι in a bacterial system. The large quantity of PKC-ι can be used for future experiments such as Nuclear Magnetic Resonance (NMR), x-ray crystallography, isothermal titration calorimetry (ITC) and ligand binding studies. Methods: We used bacterial expression plasmids (pET-His) with full-length and catalytic domain only PKC-ι gene inserts (tagged and untagged with GST). We transformed the bacterial cells lines BL21(DE3), Tuner (DE3), and ArticExpress. Results and Discussion: So far we have successfully produced low amounts of the full-length PKC-ι and the catalytic domain of PKC-ι in Tuner (DE3) and BL21(DE3) bacterial cells, respectively. We have also isolated a small amount of the PKC-ι catalytic domain from BL21(DE3) using a nickel column. However, continued optimization of the bacterial environment is needed to increase the quantity and quality of our desired protein.

Citation Format: Tracess Smalley, Rekha Patel, Mildred Acevedo-Duncan. Full-length bio-active atypical protein kinase c ι expression and purification in a bacterial system [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 B123. doi:10.1158/1535-7163.TARG-19-B123
Abstract B125: Targeting translation for the treatment of pancreatic ductal adenocarcinoma
Authors: Safari Maryam , Kim Yu Ri , Mundi Prabhjot S. , Deng Changchun , Bates Susan E.
Published: March 2020

Pancreatic ductal adenocarcinoma (PDAC) is currently the third leading cause of cancer deaths in the United States and is projected to be in second place by 2030. A key cellular aberration is the activating KRAS mutation (>90%) which in turn leads to stabilizing the MYC oncoprotein and stimulating the growth of PDAC tumors. Dense stroma with elevated levels of hyaluronic acid is another characteristic of PDAC tumors contributing to poor therapeutic response. We describe a novel approach for the treatment of PDAC involving the targeting of thetranslation initiation factor 4A (eIF4A) with a new class of Pateamine A derivatives, DMDA PatA and MZ735.Our data show that nanomolar concentrations of these compounds inhibit cell proliferation and cause G0/G1 arrest in PDAC cell lines. We observed reduction of c-MYC, CyclinD1 and hyaluronic acid synthase HAS3 following treatment with eIF4A targeting compounds. RNA-seq analysis of Miapaca-2 cells treated with MZ735 using the Virtual Inference of Protein-activity by Enriched Regulon analysis (VIPER) algorithm revealed that loss of several MYC gene sets was among the most significantly altered compared to the control cells. We further performed proteomics to better define the consequences of MZ735-induced translation inhibition and observed that several key oncoproteins in PDAC were among the most depleted including MYC, CCND1, and EGFR. Finally, confocal imaging confirmed the reduction of hyaluronic acid in the eIF4A inhibitor-treated PDAC cells. We believe these small molecule compounds represent a new class of anticancer agents that have the potential to address both altered cellular and microenvironment components in PDAC.

Citation Format: Maryam Safari, Yu Ri Kim, Prabhjot S. Mundi, Changchun Deng, Susan E. Bates. Targeting translation for the treatment of pancreatic ductal adenocarcinoma [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 B125. doi:10.1158/1535-7163.TARG-19-B125
Abstract B135: Discovery of BGS2019, a highly potent and selective covalent inhibitor of GMPS using IMTACTM platform
Authors: Chen Hang , Ha Heather , Stanley Robert , Huang Cindy , Cai Qian , Yuan Irene , Cao Ping
Published: March 2020

Guanosine monophosphate synthetase (GMPS) is a glutamine amidotransferase catalyzing amination of xanthosine monophosphate (XMP) to form GMP. It is a enzyme involved in de novo purine biosynthesis. T and B lymphocytes, and certain cancer cells, such as malignant melanoma are dependent on de novo synthesis of purine nucleotide for activation and proliferation. GMPS is an attractive target for drug discovery and development to treat autoimmune diseases, organ transplant rejection, and cancers. Mycophenolate acid (MPA), an active ingredient of Mycophenolate Mofetil (Cellcept) has been used for organ transplantation and autoimmune diseases. MPA is a natural product which inhibits inosine monophosphate dehydrogenase (IMPDH), an enzyme upstream of GMPS. Using IMTACTM (Isobaric Mass Tagged Affinity Characterization) platform to perform global proteome ligand screen in live cancer cells, a highly potent and highly selective irreversible inhibitor against GMPS was discovered. Here we report the identification, in vitro characterization and in vivo evaluation of this molecule BGS2019. Target engagement of BGS2019 was determined by In-Gel-Fluorescent assay in cell with an EC50 of 15.6nM. It inhibited GMPS enzymatic activity with an IC50 of 6nM. The mechanism of BGS2019 in cell-based assays was tested, which showed the accumulation of IMP (the substrate for GMPS) and the reduction of GMP, GDP and GTP, upon BGS2019 treatment. BGS2019 was evaluated for its cell growth inhibition activity in several cancer cell lines and it suppressed cancer cell growth with IC50 values from 30nM to 100nM. In vivo administration of BGS2019 was well tolerated in mice and exhibited tumor suppression in animal model.

Citation Format: Hang Chen, Heather Ha, Robert Stanley, Cindy Huang, Qian Cai, Irene Yuan, Ping Cao. Discovery of BGS2019, a highly potent and selective covalent inhibitor of GMPS using IMTACTM platform [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 B135. doi:10.1158/1535-7163.TARG-19-B135
Abstract C005: NT5C2 small molecule inhibitor for the reversal of 6-MP resistance in acute lymphoblastic leukemia
Authors: Dieck Chelsea , Reglero-Gomez Clara , Zask Arie , Stockwell Brent , Ferrando Adolfo
Published: March 2020

Activating mutations in the cytosolic 5’-nucleotidase II (NT5C2) gene drive resistance to chemotherapy with 6-mercaptopurine (6-MP) in acute lymphoblastic leukemia (ALL) highlighting NT5C2 as a potential therapeutic target. In efforts to reverse 6-MP therapy resistance, we performed high throughput screens to identify small molecule inhibitors of NT5C2. Using a high throughput malachite-green based NT5C2 nucleotidase assay, we identified HTP_2 as a lead compound with low micromolar inhibitory activity against NT5C2 R367Q mutant recombinant protein. HTP_2 reverses 6-MP resistance in Nt5c2+/R367Qmutant mouse lymphoblasts and NT5C2 R29Q mutant expressing human cell lines. In addition, HTP_2 treatment results in increased sensitivity to 6-MP therapy in NT5C2 wild-type cells, highlighting the role of wild-type NT5C2 activity in the clearance of 6-MP. These results support a potential therapeutic use for NT5C2 inhibitors in potentiating the effects of 6-MP based chemotherapy in NT5C2 wild-type cells as well as NT5C2 mutant cells. Overall, this study presents a framework for the development of a NT5C2 inhibitor for the reversal of 6-MP resistance in relapsed ALL patients.

Citation Format: Chelsea Dieck, Clara Reglero-Gomez, Arie Zask, Brent Stockwell, Adolfo Ferrando. NT5C2 small molecule inhibitor for the reversal of 6-MP resistance in acute lymphoblastic leukemia [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 C005. doi:10.1158/1535-7163.TARG-19-C005
Abstract C012: Real-world use of circulating tumor DNA (ctDNA) in the clinical management of patients with solid tumors: A single institution’s experience
Authors: Behdad Amir , Wehbe Firas , Williams Carmen , Qiang Wenan , Vasilopoulos Athanasios ,   Massimo Cristofanilli MD FACP
Published: March 2020

Background: The analysis of circulating tumor DNA (ctDNA) is becoming an instrumental tool in the practice of precision oncology. It not only provides a non-invasive method to study the mutational composition of solid tumors, particularly when there are limitations in tissue acquisition, but also helps capturing the biological heterogeneity and genomic evolution of advanced tumors. There is tremendous variability in utilization of ctDNA among oncologists in in various solid tumors and currently there are no guidelines. Methods: We evaluated the results of all Guardant360 ctDNA tests that were requested for clinical management in advanced cancers in our academic tertiary cancer center. We identified and annotated the most common genomic alterations and variants for each disease type. Moreover, we collected variant allele frequency variants (VAF) from each report and disease. The results for each type of neoplasm were compared to the others. Results: A total of 2199 tests for 1402 patients were performed between 2015 to January 2019. The test volume increased from 162/year in 2015 to 733/year in 2018. The tests were most commonly requested in patients with the diagnosis of advanced breast adenocarcinoma (ABC)(36%), followed by non-small cell lung cancer (NSCLC)(21%), colorectal cancer (CRC)(5%). 88% of reports included at least one alteration, with a median of 3 alterations per case and median of highest VAF of 1.1%. Prostate small cell carcinoma, contained the largest number of alterations/case (median: 9.5) and highest VAF (median: 7.1%). Among common neoplasms CRC had a significantly higher VAF (Median: 5.4%), compared to NSCLC and ABC (median <1%). Overall the most commonly mutated genes, in order of prevalence, included TP53 (90% of positive cases), PIK3CA (36%), EGFR (31%), NF1 (21%), and ERBB2 (20%). Conclusions: Utilization of ctDNA in the management of patients with solid tumors is drastically increasing. The data indicates that tests can identify genomic abnormalities in the majority of cases but, the number of mutations and VAF is variable in different types of tumors reflecting underlying biology and molecular heterogeneity. ctDNA should be used in the management of advanced solid tumors to improve understanding of disease genomic alterations and facilitate treatment selection.

Citation Format: Amir Behdad, Firas Wehbe, Carmen Williams, Wenan Qiang, Athanasios Vasilopoulos, Massimo Cristofanilli MD FACP. Real-world use of circulating tumor DNA (ctDNA) in the clinical management of patients with solid tumors: A single institution’s experience [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 C012. doi:10.1158/1535-7163.TARG-19-C012
Abstract C024: Ribitol enhances O-mannosylation of α-DG in breast cancer cells
Authors: Lu qi L , Lu Pei J , Tucker Jason D , Branch Elizabeth K , Guo Fei , Blaeser Anthony R
Published: March 2020

O-mannosylation of a-dystroglycan (α-DG) is an important modification in most tissues in mammals and plays diverse roles, from acting as viral receptors to neuronal development. The glycosylation produces a laminin-binding glycan (matriglycan) identified in nearly all epithelial cells in a differentiation-related manner. Reduction or loss of matriglycan has been implicated in cancer development and metastasis, and specifically associated with high-grade tumors and poor prognoses in breast cancers. Enhancing matriglycan expression has been proposed as potential therapeutics. In the current study, we demonstrate that ribitol, considered to be an end product of metabolism, increases levels of CDP-ribitol, the substrate for the ribitol-5-phosphate transferases FKRP and FKTN, and consequently significantly enhances the expression of matriglycan in the MCF7 breast cancer cells. This effect is FKRP and LARGE dependent and ribitol treatment does not alter the expression of glycosyltransferases known to be critical for the synthesis of matriglycan. Enhanced expression of matriglycan is related to cell cycle progression with highest levels in S and G2 phases. This is the first time that glycosylation of a-DG is shown to be up-regulated in cancer cells by a metabolite. Our data show another layer of modulation and illustrate the complexity of matriglycan expression in cancer cell proliferation and progression.

Citation Format: qi L Lu, Pei J Lu, Jason D Tucker, Elizabeth K Branch, Fei Guo, Anthony R Blaeser. Ribitol enhances O-mannosylation of α-DG in breast 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 C024. doi:10.1158/1535-7163.TARG-19-C024
Abstract C034: Cancer-specific intracellular delivery of therapeutic antibodies against RAS
Authors: McGuire Michael J , Li Susan , Allred Curtis A , Venugopal Indu , Gormley Claire , Brown Kathlynn C
Published: March 2020

Antibodies and peptides directed against the switch regions of RAS can disrupt interactions with its downstream effector proteins, blocking downstream pro-tumorigenic signaling. However, these biologic therapies are unable to reach the intracellular environment. We have overcome this problem using peptidic molecular guidance system (MGSs) that have the unique ability to bind specifically to epithelial-derived cancer cells, and upon binding, trigger rapid internalization and trafficking to a specific subcellular location. Using an unbiased phage display approach, we have identified a series of cancer specific MGSs that deliver cargo to discrete subcellular locations. Chemical optimization results in MGSs with 1-10 nM affinity for their cellular target, serum stability >48 hours, and 50-1000-fold specificity for cancer cells compared to normal control cells. The rate of MGS internalization is rapid with t1/2 of 10-30 minutes, achieving intracellular concentrations up to 1.5 µM. Using these MGSs as delivery agents, we have delivered a function blocking RAS antibody (Y13-259), resulting in a reduction of p-ERK and apoptosis in KRAS mutant cell lines. The effect is MGS dependent. The MGS-Antibody homes to tumors in an animal model resulting in significant suppression in tumor growth compared to untreated animals. Free MAb does not impact tumor growth. Using MGSs to delivery MAb for intracellular targets is a paradigm change for immunotherapy and represents a new approach for controlling intracellular protein-protein interactions. Combination of these cancer-specific delivery agents with effectors of RAS signaling, such as antibodies and other biologics, has therapeutic potential for KRAS-driven cancers.

Citation Format: Michael J McGuire, Susan Li, Curtis A Allred, Indu Venugopal, Claire Gormley, Kathlynn C Brown. Cancer-specific intracellular delivery of therapeutic antibodies against RAS [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 C034. doi:10.1158/1535-7163.TARG-19-C034
Abstract C068: Toward precision medicine for platinums
Authors: Koblinski Jennifer E , Peterson Erica J , Hampton James D. , Harrell J Chuck , Farrell Nicholas P
Published: March 2020

Over half of all cancer patients will receive a platinum drug during their treatment. Recent interest in our labs involve exploiting the high affinity of a discrete class of platinum-based anticancer agents, polynuclear platinum complexes (PPCs), for sulfated glycosaminoglycans (sGAGs). sGAGs are increasingly seen as potential biomarkers and molecular targets in many forms of cancer. sGAG expression levels were quantified in patient derived xenograft (PDX) and cellular models of triple negative breast cancer (TNBC) and ovarian cancer. PPCs, but not carboplatin, show increased levels of tumor uptake and efficacy in models expressing high levels of sGAGs. sGAGs may provide a viable target for PPCs, producing a significant advantage over clinical platinum agents in this setting.

Citation Format: Jennifer E Koblinski, Erica J Peterson, James D. Hampton, J Chuck Harrell, Nicholas P Farrell. Toward precision medicine for platinums [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 C068. doi:10.1158/1535-7163.TARG-19-C068
Abstract C070: CLR 180099, a lipid raft targeted phospholipid-drug conjugate, shows potent improved safety and efficacy against colorectal tumors
Authors: Longcor Jarrod , Pinchuk Anatoly , Hoover Randall , Friend John
Published: March 2020

Lipid rafts (LR) are specialized regions or microdomains within the cell membrane that are highly enriched with cholesterol and sphingolipids. The presence of LR in tumor cell membranes is as much as 10 fold higher than in normal tissue. Our phospholipid ether (PLE) molecules [18-(p-iodophenyl)octadecyl phosphocholine] have a high affinity for binding and being transported into cells via LRs(1). In this study, we report the development of CLR 180099, a LR targeting phospholipid-drug conjugate (PDC), consisting of a PLE with a cleavable peptide linker (non-cathepsin cleavage) bound to a flavagline (FLV) analogue, a highly potent inhibitor of cell proliferation and simulator of apoptosis. We first study the presence of LR on a large panel of cancer cell lines. Then, we evaluated the uptake of multiple PLE conjugates in a similar panel of cancer cell lines. Then CLR 180099 was assessed for uptake and the release of the FLV in in vitro tumor cell lines. Finally, we present a series in vitro anti-proliferation assays in multiple cell lines and in vivo tolerability as compared to free FLV and efficacy of CLR 180099 in HCT 116 colorectal cancer xenograft. Presence of LR was found to be determinant in the sensitivity of tumor cells to the cytotoxic effect of the PDC. Importantly, CLR 180099 demonstrated significant improvement in tolerability of FLV versus free FLV. These results suggest that PLEs could be used to make PDCs that improve tolerability and efficacy of the warhead molecule. The ability to specifically deliver a variety of warheads/payloads to a broad range of tumor cells offers a unique advantage of PDCs. These findings support the continued development of CLR 180099 PDC as a novel targeted therapy. The PDC described in this abstract is investigational, as efficacy and safety have not been established. There is no guarantee that this PDC will be available commercially.

Citation Format: Jarrod Longcor, Anatoly Pinchuk, Randall Hoover, John Friend. CLR 180099, a lipid raft targeted phospholipid-drug conjugate, shows potent improved safety and efficacy against colorectal tumors [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 C070. doi:10.1158/1535-7163.TARG-19-C070
Abstract C072: Discovery of highly potent and selective covalent inhibitors of FGFR4
Authors: Chen Hang , Slemmons Katherine , Ha Heather , Stanley Robert , Cai Qian , Yuan Irene , Helman Lee , Cao Ping
Published: March 2020

Hepatocellular carcinoma (HCC) accounts for 65% of all cases of liver cancers, ranking the 6th most common cancer and the 2nd cause of cancer mortality. HCC has more than 700,000 new cases/year and 600,000 deaths/year. Sorafenib is currently the standard of care for advanced disease, provides a response rate of ~2% and median survival <11 months. The fibroblast growth factor 19 (FGF19)-fibroblast growth factor receptor 4 (FGFR4)-Klotho β (KLB) signaling pathway regulates bile acid synthesis and is also a key driver in certain subtypes of HCC (around 30%). We generated BGS2219 and BGS2223 through FGFR4 structure-based design. BGS2219 and BGS223 are potent, selective and irreversible FGFR4 inhibitors. BGS2219 inhibits FGFR4 with an IC50 of 4nM and has greater than 2500 fold selectivity over FGFR1, 2 and 3. BG2219 took effects in both HCC and RMS tumor cell lines. In vivo administration of BG2219 was well tolerated in mice at all dosages with no body weight loss and and inhibited tumor growth in a dose -dependent fashion in HCC xenograft model. Complete tumor regression was observed at 40mg/kg. BGS2219 was tested in a combo therapy regimen with R1507 (anti-IGFR1 mab) in RMS (rhabdomyosarcoma) xenograft model in mice and showed that BG2219 plus R1507 significantly reduce the tumor volume in comparison with R1507 alone. BGS2223 is derived from BG2219, with improved oral bioavailability. BGS2223 has no hit in Cerep Screen safety panel and no activity detected in hERG assay at 10mM. In vivo oral administration of BG2223 in mice was well tolerated with no body weight loss and showed dose-dependent tumor growth inhibition in HCC CDX model at all dosages. Tumor regression was achieved at high dose treatment. BGS22 treatment in vivo in HCC tumor bearing mice caused alteration of CYP7A1 and FGF19 expression, which were utilized as biomarkers for FGFR4 inhibition.

Citation Format: Hang Chen, Katherine Slemmons, Heather Ha, Robert Stanley, Qian Cai, Irene Yuan, Lee Helman, Ping Cao. Discovery of highly potent and selective covalent inhibitors of FGFR4 [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 C072. doi:10.1158/1535-7163.TARG-19-C072
Abstract C080: The combination of MEK and MDM2 inhibitors demonstrates promising antitumor efficacy in MAPK altered patient-derived thyroid and colorectal cancer models
Authors: Pairawan Seyed , Evans Kurt , Kopetz Scott , Akcakanat Argun , Zhao Ming , Tapia Coya , Busaidy Naifa , Dumbrava Ecaterina , Meric-Bernstam Funda
Published: March 2020

Purpose: Genomic alterations in the mitogen activated protein kinase (MAPK) pathway are common in colorectal and thyroid cancer. However MEK inhibition alone has limited efficacy. We investigated the combinatorial antitumor efficacy of MEK (Selumetinib; AZD6244) and MDM2 inhibition (AMG232) in wild-type TP53 colorectal and thyroid cancers with MAPK alterations. Methods: One thyroid (BRAF mutated) and three colorectal cancer cell lines (KRAS mutated) were used to evaluate the anti-tumor effect of selumetinib combined with AMG232 in vitro. Sulforhodamine B and colony formation assays were utilized to determine the cytotoxicity of each single targeted agent and combination and to obtain the half maximal inhibitory concentration (IC50). The efficacy of the combination was evaluated in athymic mice with subcutaneously implanted patient-derived xenografts (PDX) of different histologic backgrounds (5 colorectal and 2 thyroid cancer) and with different genomic MAPK pathway alterations. Selumetinib (25 mg/kg in 6 models, and 15 mg/kg in 1 model) and AMG232 (15 mg/kg) were administered daily through oral route. Results: Selumetinib demonstrated synergistic activity with AMG232 across all four cell lines with combination indices ranging from 0.37 to 0.72. The antitumor efficacy was enhanced when combining the two agents in all seven PDX models and achieved statistical significance in six of seven PDX models compared to either single agent therapy alone. Treatment/Control ratio % ((median tumor volume of treatment group / control group) x 100) was obtained from each combination arm across in vivo experiments (31 % (range 12%-62%)) and it was greater than monotherapy alone (Selumetinib 51%; range 21%-76%, AMG232 77%; range 38%-100%). Conclusions: Our preclinical findings demonstrate enhanced anti-tumor efficacy when combining Selumetinib with AMG232, which supports further evaluation of MEK/MDM2 inhibition in patients with MAPK altered colorectal and thyroid cancer with wild-type TP53 status.

Citation Format: Seyed Pairawan, Kurt Evans, Scott Kopetz, Argun Akcakanat, Ming Zhao, Coya Tapia, Naifa Busaidy, Ecaterina Dumbrava, Funda Meric-Bernstam. The combination of MEK and MDM2 inhibitors demonstrates promising antitumor efficacy in MAPK altered patient-derived thyroid and colorectal 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 C080. doi:10.1158/1535-7163.TARG-19-C080
Abstract C117: Development of autologous tumor: TIL coculture from patient-derived samples for in vitro preclinical immuno-oncology studies
Authors: Hinata Kaede , Cuff Patrice , Liang Wei , Broudy Thomas
Published: March 2020

For over two decades, tumor infiltrating lymphocytes (TILs) have been utilized as an adoptive cell transfer therapy to treat cancer in clinical trials. In combination with added immunotherapy treatments, such as IL-2 or anti-CTLA4, TIL therapy has further improved clinic response rate. Following isolation from a patient’s own tumor specimen, TILs that recognize tumor-specific known or unknown antigens can be expanded. These cells are then infused back into tumor-bearing patients to attack the autologous cancer cell population. Despite progress in clinical research, preclinical and translational models of autologous tumor:TIL coculture have been difficult to establish. Our present study established autologous tumor:TIL coculture methods directly from patient tumor specimens. Models were established from BioDuro’s viably frozen tumor bank, containing more than 100,000 patient biospecimens. Each patient specimen contains a heterogeneous population of cell types, including tumor cells, TILs and TAFs (tumor associated fibroblasts). To establish our patient-derived coculture system, these cell populations were expanded under specific growth conditions to then serve as components of the coculture system. In this study, TILs and monocytes from a cohort of patient tumor specimens were analyzed by FACS to evaluate surface receptor expression. Leukocytes, T cells, monocytes and B cells were marked with CD45, CD3, CD14, CD20, respectively. PD-1 expression levels were also evaluated, with the results showing significant individual variation of expression on cell subpopulations. Established methods were used for the expansion of TILS, supporting either CD4 or CD8 T cell phenotypes. Autologous tumor cells were also expanded, concurrently. Afterward, TILs and tumor cells were cocultured and tumor cell killing was monitored using high content fluorescent image cytometry. We found that autologous patient-matched TILs showed preferential tumor cell killing as compared to coculture with patient-unmatched TILs. This response was observed in a dose-dependent manner. In conclusion, BioDuro’s biobank of viably frozen tumor and TIL patient specimens serves as an expansive and powerful immunooncology resource to establish patient-derived autologous tumor:TIL coculture assays. These assays, along with the ability to readily study larger populations of cancer patients, provide a powerful in vitro platform to test immunooncology drug candidates.

Citation Format: Kaede Hinata, Patrice Cuff, Wei Liang, Thomas Broudy. Development of autologous tumor: TIL coculture from patient-derived samples for in vitro preclinical immuno-oncology studies [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 C117. doi:10.1158/1535-7163.TARG-19-C117
Abstract C118: Transcriptome comparison of orthotopic and subcutaneous patient-derived xenografts
Authors: jiang xiaoqian , li henry , guo sheng
Published: March 2020

Background: Patient-derived xenograft (PDX) models are used for in vivo evaluation of oncology drugs. Tumors from cancer patients are implanted into immunodeficient mice either subcutaneously or orthotopically. Subcutaneous PDX models are more prevalently used because of easy operation and monitoring, albeit increasing evidence showed that the immune microenvironment in subcutaneous tissue is different from the original tract and is therefore less patient-like. By contrast, orthotopic PDX models have the capability to metastasize and match that of the donor patient well, but resulting in extensive inflammation. Previous studies showed that tumor location may affect immune response or result in different behavior of tumor expansion in mouse models [1-4]. There is yet insufficient study on the transcriptomic difference between subcutaneous and orthotopic PDX models. Method: Tumors for 10 PDX models—including four breast, four colorectal, and two liver cancers—were used to establish pairs of subcutaneous and orthotopic models. Tumors were dissected when reaching about 1000mm3, and subjected to transcriptomic profiling by RNAseq for gene expression comparison. Results: Using traditional alignment-based RNAseq analysis, we found hundreds of genes with different expression levels between subcutaneous and orthotopic models for the three cancers. Gene ontology analysis revealed that these differentially expressed genes are highly enriched in protein translation related biological processes and pathways, such as maturation of SSU-rRNA, cap-dependent translation initiation, and peptide chain elongation. Conclusion: Subcutaneous and orthotopic PDX models differ in transcriptomes that may affect protein translation and warrant further proteomics investigations. Reference: 1, Zhang, Yong, et al. “Real–Time GFP Intravital Imaging of the Differences in Cellular and Angiogenic Behavior of Subcutaneous and Orthotopic Nude–Mouse Models of Human PC–3 Prostate Cancer.” Journal of cellular biochemistry 117.11 (2016): 2546-2551. 2, Zhao, Xianda, et al. “Tumor location impacts immune response in mouse models of colon cancer.” Oncotarget 8.33 (2017): 54775. 3, Zhang, Yi, et al. “Establishment of a murine breast tumor model by subcutaneous or orthotopic implantation.” Oncology letters 15.5 (2018): 6233-6240. 4, Nakano, Kiyotaka, et al. “Difference in morphology and interactome profiles between orthotopic and subcutaneous gastric cancer xenograft models.” Journal of toxicologic pathology 31.4 (2018): 293-300.

Citation Format: xiaoqian jiang, henry li, sheng guo. Transcriptome comparison of orthotopic and subcutaneous patient-derived xenografts [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 C118. doi:10.1158/1535-7163.TARG-19-C118