bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 2581: VGLL4 suppresses the human breast cancer progression through the inhibition of YAP oncogenic function
Authors: Zhang Jianmin
Published: July 2017

VGLL4 is a Vestigial-like (VGLL) protein that is deregulated in various types of cancer. However, the functions of VGLL4 in breast cancer remain largely unknown. Here, we demonstrate that VGLL4 expression positively correlates with survival for breast cancer patients. The overexpression of VGLL4 in breast cancer cells reduced cell proliferation, colony formation, cell migration and invasion in vitro and inhibited tumor growth in vivo. We found that the 2nd TEAD-interacting domain (TDU2) of VGLL4 is involved in interactions between VGLL4 and the transcription factor TEAD and that the deletion of this domain completely abolished the phenotype induced by VGLL4 overexpression. Interestingly, RNAseq analysis indicated that VGLL4 overexpression not only inhibits YAP targets but also activates the TGF-β and Notch signaling pathways. Our study provides evidence of the tumor-suppressive effects of VGLL4 on breast cancer progression and suggests that VGLL4 and its TDU2 domain may become promising and efficient therapeutic targets for delaying the development of breast cancer and improving patient survival.

Citation Format: Jianmin Zhang. VGLL4 suppresses the human breast cancer progression through the inhibition of YAP oncogenic function [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2581. doi:10.1158/1538-7445.AM2017-2581
Abstract 2604: The Georgetown Database of Cancer (G-DOC): A web-based data sharing platform for precision medicine
Authors: Bhuvaneshwar Krithika , Belouali Anas , Rao Shruti , Alaoui Adil , Gusev Yuriy , Clarke Robert , Weiner Louis M. , Madhavan Subha
Published: July 2017

Introduction An overarching goal of biomedical research is to improve the use and dissemination of rapidly growing biomedical datasets to support precision medicine. Individualized molecular profiling and the identification of predictive biomarkers can powerfully inform the choice of therapies for cancer patients. However, both require integration of extensive molecular, clinical, and pharmacological data, often from disparate and diverse sources. The Georgetown Database of Cancer (G-DOC) was designed and engineered to be a unique multi-omics data analysis platform to enable translational research and precision medicine.

Methods G-DOC is home to 61 datasets that contain data from over 10,000 patients across 14 diseases (10 cancers and 4 non-cancers). 1700+ researchers from over 48 different countries worldwide currently use the platform. The data and tools in the G-DOC system have enabled over 40 research publications. G-DOC has the largest public collection of brain cancer patients from NCI Rembrandt dataset (671 patients).G-DOC integrates clinical, transcriptomic, metabolomic, microRNA, next generation sequencing (NGS) data, and MRI medical images with systems-level analysis tools into a single, user-friendly platform. The “Variant Search” feature in G-DOC currently enables exploratory analysis of mutations based on genes, chromosomes, and functional location. A researcher can use this feature to 1) identify clinically actionable mutations in their dataset 2) identify pathways that may be affected by these mutations, and 3) identify novel mutations in their dataset and explore their potential impact on protein function.

Results and Conclusion We are currently working on developing features to support the import, integration, search, and retrieval of CLIA/CAP-certified cancer molecular diagnostic (molDx) data. This will enhance G-DOC’s interoperability with clinical and patient molecular profiling data that may be already stored in other databases. Our vision is to continuously improve and expand G-DOC with the long-term vision of supporting integration of informatics techniques into everyday research and practice.

Citation Format: Krithika Bhuvaneshwar, Anas Belouali, Shruti Rao, Adil Alaoui, Yuriy Gusev, Robert Clarke, Louis M. Weiner, Subha Madhavan. The Georgetown Database of Cancer (G-DOC): A web-based data sharing platform for precision medicine [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2604. doi:10.1158/1538-7445.AM2017-2604
Abstract 2610: A database for evaluating methylation biomarkers in bladder cancer
Authors: Kennedy Meaghan M. , Dancik Garrett M.
Published: July 2017

Bladder cancer is the fourth-most common cancer in men, one of the most expensive types of cancer to treat, and recurs frequently. While the genomic pathways associated with high-grade, muscle invasive (MI) tumors and low-grade, non-muscle invasive (NMI) tumors are well-established, recent studies have also found that MI and NMI tumors have unique methylation patterns, and that methylation may play a role in the development of early-stage bladder cancer. Interestingly, bladder cancer patients have frequent mutations in chromatin remodeling genes that alter known histone markers of DNA methylation. Since methylation marks are pharmacologically reversible, the identification of methylation biomarkers is a promising avenue for therapeutic treatment. Indeed, several candidate prognostic methylation biomarkers have been identified, but await prospective evaluation.

The Bladder Cancer Biomarker Evaluation Tool (BC-BET) is a web-based resource for rapidly evaluating biomarkers in publicly available genomic datasets. Initially developed for gene expression biomarkers, BC-BET includes 1451 patients across 13 cohorts, and 40 bladder cancer cell lines, with gene expression profiles. In this work, we describe the addition of methylation data to BC-BET, so that candidate methylation biomarkers can be rapidly evaluated across multiple patient cohorts.

BC-BET now contains methylation profiles from four patient cohorts (250 patients) and includes the available bladder cancer data from the Gene Expression Omnibus and The Cancer Genome Atlas. In "evaluation" mode, a user selects a gene of interest, and BC-BET evaluates whether the selected gene is differentially methylated between tumor vs. normal samples, NMI vs. MI tumors, and low- vs. high-grade tumors. Alternatively, the “biomarker discovery” mode allows a user to identify all differentially methylated genes at a desired false discovery rate (FDR). In both cases, graphical summaries of the results are displayed and statistical results can be downloaded to an Excel spreadsheet. The methylation module of BC-BET is implemented using shiny, a web application framework for R for developing interactive web pages.

The addition of methylation data to BC-BET makes it a valuable resource for evaluating methylation biomarkers in bladder cancer. BC-BET is available from the following link: https://gdancik.github.io/bioinformatics/BCBET

Citation Format: Meaghan M. Kennedy, Garrett M. Dancik. A database for evaluating methylation biomarkers in bladder cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2610. doi:10.1158/1538-7445.AM2017-2610
Abstract 2634: EVT801: Standalone cancer immunotherapy in VEGFR3+ tumors and combination with immune checkpoint therapies in VEGFR3- tumors
Authors: Esquerré Michael , Fons Pierre , Badet Gaëlle , Barron Pauline , Kagan Jérémy , Alam Antoine , Meneyrol Jérôme , Blanc Isabelle , Broussy Roselyne , Gaujarengues Florence , Lisztwan Joanna , Paillasse Michael , Whittaker Mark , Bono Françoise
Published: July 2017

In collaboration with Sanofi, we previously showed that inhibition of the VEGFR3 pathway by SAR131675 leads to reduction of tumor growth by acting on the tumor microenvironment. We have identified a new drug candidate, EVT801, and evaluated its activity on tumor models expressing VEGFR3. For proof-of-concept, we transfected the mouse BNL hepatoma cell line with VEGFR3. EVT801 displayed a strong therapeutic activity by acting on both VEGFR3+ tumor cells and on the Tumor Microenvironment (TME). By deciphering the mechanism of action of the compounds we showed that EVT801 strongly decreased tumor-associated immunosuppression by decreasing MDSCs (Myeloid Derived Suppressor cells) and CD4+ regulatory T cells and by increasing macrophages with a M1 phenotype inside the tumor. As a consequence the T-cell:MDSC ratios were increased in the TME and also in peripheral blood. In addition to its immunomodulatory properties, EVT801 decreased angiogenesis without increasing hypoxia. We have evaluated EVT801 therapeutic activity in syngeneic tumor mouse models which are not expressing VEGFR3 such as 4T1 mammary carcinoma and CT26 colon carcinoma models. As expected, we observed an intermediate therapeutic activity of the compound on both tumor models. Positive modulation of the TME was equivalent to what we observed with the VEGFR3+ tumor model. With this unique mechanism of action of EVT801 on the TME, we evaluated its ability to increase therapeutic activity of standard Immune Checkpoint Therapies (ICT) such as anti-CTLA-4 and anti-PD-1 mAbs. Strong additive therapeutic activities were observed with EVT801 in combination with these ICT as illustrated by the development of long-term tumor-specific memory CD8+ T cell responses.

Toxicological data show that EVT801 has a favorable pharmacological profile consistent with its entry into pre-clinical development. Taken together, these results indicate that EVT801 represents an innovative drug for cancer Immunotherapy which provide a favorable microenvironment to promote tumor regression. In addition, EVT801 may improve the frequency of response to ICT.

Citation Format: Michael Esquerré, Pierre Fons, Gaëlle Badet, Pauline Barron, Jérémy Kagan, Antoine Alam, Jérôme Meneyrol, Isabelle Blanc, Roselyne Broussy, Florence Gaujarengues, Joanna Lisztwan, Michael Paillasse, Mark Whittaker, Françoise Bono. EVT801: Standalone cancer immunotherapy in VEGFR3+ tumors and combination with immune checkpoint therapies in VEGFR3- tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2634. doi:10.1158/1538-7445.AM2017-2634
Abstract 2639: Development of small molecule selective inhibitors of GCN2 as an immunotherapy aimed at preventing immune escape of tumor cells
Authors: Gałęzowski Michał , Sitarz Kamil , Majewska Eliza , Chmielewski Stefan , Michalik Kinga , Masiejczyk Magdalena , Adamus Agnieszka , Białas Arkadiusz , Fogt Joanna , Bień Marcin , Świrski Mateusz , Mikulski Maciej , Zachmann Julian , Brzózka Krzysztof
Published: July 2017

GCN2 is a protein kinase capable of sensing amino acid (AA) shortage. It gets activated by binding of unloaded tRNAs and subsequently phosphorylates translation initiation factor 2 alpha (eIF2α) eventually leading to induction of ATF4-mediated integrated stress response (ISR). Elevated catabolism of one of the essential amino acids - tryptophan (Trp), driven by overexpression of critical enzymes in Trp metabolism - IDO and TDO, leads to immunosuppressive microenvironment in many types of cancer. GCN2 is a key effector signaling component for IDO/TDO and is considered as a metabolic checkpoint of highly Trp-dependent T-cells. GCN2 activation through accumulation of unloaded tRNAs leads to inhibition of CD8+ effector T-cells and increase in generation and activation of regulatory T-cells. According to these findings, selective inhibition of GCN2 may be an effective strategy for targeting Trp-dependent immunosurveillance of tumor cells. In this study, we report the results for a series of novel small molecule GCN2 kinase inhibitors that have been developed at Selvita and, to our best knowledge, are the most potent GCN2 inhibitors reported so far. Newly synthesized compounds exert low nanomolar potency for GCN2, good selectivity as well as ADME profiles. Profound assessment of the compounds potency and efficacy using a selection of in vitro activity/binding assays will be presented.

Citation Format: Michał Gałęzowski, Kamil Sitarz, Eliza Majewska, Stefan Chmielewski, Kinga Michalik, Magdalena Masiejczyk, Agnieszka Adamus, Arkadiusz Białas, Joanna Fogt, Marcin Bień, Mateusz Świrski, Maciej Mikulski, Julian Zachmann, Krzysztof Brzózka. Development of small molecule selective inhibitors of GCN2 as an immunotherapy aimed at preventing immune escape of tumor cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2639. doi:10.1158/1538-7445.AM2017-2639
Abstract 2648: CD47 antibody-induced engulfment of human T-cell leukemia cells by bone marrow-derived macrophages
Authors: Lovell Gillian , Szybut Clare , Patel Kalpana , Campwala Hinnah , Bevan Nicola , Appledorn Dan , Dale Tim James , Trezise Derek John
Published: July 2017

CD47 is a trans-membrane “don’t-eat-me” signaling protein that enables tumor cells to evade clearance by neighboring phagocytes. Blocking CD47 allows phagocytes to identify and clear tumor cells and is a promising new approach for cancer immunotherapy. In this study, we characterized anti-CD47 antibody-mediated engulfment of living tumor cells (CCRF-CEM) by mouse bone-marrow derived macrophages (BMDMs) or immortalized mouse macrophages (J774A.1). Phagocytosis was quantified using a pH-sensitive cell-labeling fluorescent probe, pHrodo, and automated kinetic live-cell analysis (IncuCyte). CCRF-CEM cells were first labeled using pHrodo (250ng ml-1 for 1h), washed and then treated with antibody for 1 h. Target cells were then added to BMDMs or J774A.1 that had been seeded overnight on 96-well plates. Phase- and fluorescence images were captured and quantified every 15min. Anti-CD47 antibody (B6H12.2, 0.04-5μg ml-1), but not IgG-control, produced time- and concentration-dependent engulfment of CCRF-CEMs by BMDMs (30’-4h), as evidenced by an increase in intracellular fluorescence as the label accumulates in the acidic phagosome. After 4h the red fluorescence area was increased by 25-fold (1975 ± 391 μm2 vs 80 ± 41 μm2). From close inspection of the time-lapse images cellular engulfment could be clearly observed, coincident with the appearance of the fluorescent signal. Similar observations were made with J774A.1 as the effector cell. Interestingly, the rate and degree of engulfment appeared effector cell-dependent. The mechanism of engulfment was not via induction of target cell apoptosis since anti-CD47 did not induce PS externalization (Annexin V) or activate caspase 3/7. Anti-CD47 had no direct effect on CCRF-CEM proliferation for the first 4 h but upon longer exposures (>8 h) cell growth was attenuated. Our experimental findings substantiate the known pro-phagocytic effects of anti-CD47 antibodies, and provide a model system and method for quantitative functional analysis and mechanistic insight of CD47 modulators as cancer therapeutics.

Citation Format: Gillian Lovell, Clare Szybut, Kalpana Patel, Hinnah Campwala, Nicola Bevan, Dan Appledorn, Tim James Dale, Derek John Trezise. CD47 antibody-induced engulfment of human T-cell leukemia cells by bone marrow-derived macrophages [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2648. doi:10.1158/1538-7445.AM2017-2648
Abstract 2738: A commutable circulating tumor DNA (ctDNA) reference material
Authors: Konigshofer Yves , Tomson Farol L. , Ryder Matthew , Garlick Russell , Anekella Bharathi
Published: July 2017

We developed and assessed a novel ctDNA reference material that was designed with an emphasis on commutability. Possessing qualities that are well-matched with clinical specimens is critical for a reference material, however many existing methods of preparing ctDNA analogues result in material that is not commutable for certain assays. For example, sonication of genomic DNA yields fragments across a broad range of sizes that must be used at greater input amounts relative to native cell-free DNA (cfDNA) - even after enzymatic end-repair to reduce damage. This can affect the utility of the reference material for assays that depend on the ligation of adapters to double-stranded DNA, such as many hybrid/capture-based Next Generation Sequencing (NGS) assays. If higher input amounts are not used, then the LOD and precision of such an assay may appear substantially poorer than expected. At the same time, sonicated DNA has been shown to be acceptable for amplicon-based ctDNA assays.

We created commutable ctDNA reference material by starting with genomic DNA from GM24385 cells and mixing with synthetic variant-containing DNA sequences at defined ratios. The use of GM24385 cells allows for the comparison of detected variants against the NIST RM 8391 high confidence variants. The use of synthetic DNA permits addition of large numbers of different cancer-associated variants at defined allele frequencies. Fragmentation was followed by size-selection in order to obtain ctDNA-like sizes. Additional steps were performed to increase the amount of output material from the size-selection step. The general method of preparing the reference material is also compatible with native cfDNA, such as that isolated from cancer patients.

The reference material was submitted to several testing laboratories along with similar sonicated material. When tested using hybrid/capture-based assays, variant detection was superior in the novel reference material compared to sonicated DNA when similar amounts of material were used as the input. We therefore conclude that our new reference material has greatly improved commutability compared to existing materials composed only of sonicated DNA.

Citation Format: Yves Konigshofer, Farol L. Tomson, Matthew Ryder, Russell Garlick, Bharathi Anekella. A commutable circulating tumor DNA (ctDNA) reference material [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2738. doi:10.1158/1538-7445.AM2017-2738
Abstract 2773: A prospective observational study evaluating c-MET expression and EGFR gene mutation correlation with erlotinib response in second line treatment for advanced/metastatic non-small cell lung cancer patients
Authors: Park Cheol-Kyu , Choi Yoo-Duk , Oh In-Jae , Lee Jung-Eun , Lee Shin Yup , Jang Tae-Won , Ryu Jeong-Seon , Kim Young-Chul
Published: July 2017

Background: The c-MET is associated with tumor progression and acquired resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs). The aim of this study was to evaluate the prevalence and predictive role of c-MET and EGFR mutation in non-small cell lung cancer (NSCLC).

Methods: This was a multicenter prospective observational study for patients with stage IV or recurrent NSCLC who had progressive disease after 1st line chemotherapy and was followed by erlotinib for 2nd line treatment from September 2011 to September 2014. The primary outcome was to measure the rates of c-MET expression/amplification and EGFR mutation in tumor tissue. MET expression was evaluated by immunohistochemistry (IHC) and gene copy number was assessed by silver in situ hybridization (SISH). EGFR mutations were analyzed by Cobas™ version 1.

Results: A total of 196 patients were enrolled and major histologic types were adenocarcinoma (67%). c-MET was overexpressed (MET IHC-positive) in 44.4% of the patients and dominant in female and non-squamous histology. c-MET amplification and high polysomy (MET SISH-positive) were observed in 1.5% and 8.7%, but there was no specific clinical characteristics. The detection rate of EGFR mutation was 10.2% (19 deletion: 11, L858R: 7, exon 20 insertion: 2 cases). The response rate of erlotinib was significantly higher in EGFR sensitive mutant group (55% vs. 4%, p<0.001) and the median progression-free survival (PFS) was significantly longer than wild type (173 vs 58 days, p<0.001). c-MET positivity (IHC- or SISH-positive) did not show significant correlation with response or PFS. Patients with SISH-positive for c-MET tended to have shorter overall survival (OS) than patients with SISH-negative (127 vs 303 days, p=0.051).

Conclusion: In this observational study with 2nd line erlotinib treatment, we reconfirmed EGFR mutation is strong predictive marker, and EGFR-TKI use in EGFR wild-type patients should be considered carefully and may be harmful. c-MET overexpression was related to some clinical characteristics such as female and non-squamous histology. Although c-MET positivity was not associated with response or PFS, c-MET SISH may be predictive marker for OS.

Citation Format: Cheol-Kyu Park, Yoo-Duk Choi, In-Jae Oh, Jung-Eun Lee, Shin Yup Lee, Tae-Won Jang, Jeong-Seon Ryu, Young-Chul Kim. A prospective observational study evaluating c-MET expression and EGFR gene mutation correlation with erlotinib response in second line treatment for advanced/metastatic non-small cell lung cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2773. doi:10.1158/1538-7445.AM2017-2773
Abstract 2791: CDC25A overexpression is correlated with tumor response to radiotherapy in locally advanced rectal cancer
Authors: Huang Ming-Yii
Published: July 2017

Background. Radiotherapy is increasingly used in preoperative approaches for locally advanced rectal cancer to reduce local recurrence. However, the principal limitation is large variability in response among different individuals due to tumor heterogeneity. In current study, we compared gene expression profiles between radiation responder and non-responder in cancerous tissues to identify radiation-related molecules that can be used to evaluate the tumor response of radiation.

Methods. We investigated five genes (CDC25A, VAV1, TP73, BRCA1 and ZAP70) which were significantly related to prognostic factors (tumor size, advanced stage, invasive depth, lymph node metastasis and differentiation) from 110 colorectal cancer tissues confirmed by membrane array and RT-PCR methods in our previous study. Therefore, we further investigate those protein overexpressions by immunohistochemical stain in pretherapeutic rectal cancerous tissues. The expression profiles were evaluated according to the frequency of positive staining in the cytoplasm and/or nucleus of cancer cells. Its expression was classified as positive in cases with more than 50% positive-stained cells, with other samples being classified as negative. Cancer tissues that expressed scores of + were regarded as the overexpression group, whereas those with scores of negative staining were regarded as the non-overexpression group.

Results. We focused on these 5 genes and validated data with pretherapeutic biopsies from 36 locally advanced rectal cancer patients, and found that overexpression of CDC25A, VAV1 and ZAP70 were correlated with tumor response (P=0.001, 0.033, and 0.016, respectively). The multivariate logistic regressions with adjustment of age, sex and stage, CDC25A overexpression more than 2-fold were significantly correlated with tumor response (OR = 2.667, 95%CI = 1.591-4.470, P=0.03). Positive findings of CDC25A immunohistochemistry stain were also present in the tumor specimens of responders.

Conclusion. We identified radiation-related genes in rectal cancer and demonstrated that CDC25A may play an important role in response to radiotherapy. These findings suggest that CDC25A may be a novel marker for predicting the effectiveness of radiotherapy in clinical patients.

Note: This abstract was not presented at the meeting.

Citation Format: Ming-Yii Huang. CDC25A overexpression is correlated with tumor response to radiotherapy in locally advanced rectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2791. doi:10.1158/1538-7445.AM2017-2791
Abstract 2809: Role of c-Met in the development and progression of Tpl2-related skin cancer
Authors: Bonan Nicole F. , Kowalski David , Kudlac Kaitlin , Falkenberg Lauren G. , Maradiaga Erik , Flaherty Kira , Wiest Jonathan S. , DeCicco-Skinner Katie L.
Published: July 2017

Cutaneous squamous cell carcinoma (cSCC), a form of non-melanoma skin cancer, is the second most common form of cancer in the United States, with over one million cases diagnosed annually. Tpl2 (MAP3K8) is a serine threonine protein kinase in the mitogen-activated protein kinase (MAPK) signal transduction cascade. Tpl2 was identified by our laboratory as having a tumor suppressive function in skin carcinogenesis, with Tpl2 knockout mice developing significantly more papillomas and squamous cell carcinomas than matched wildtype (WT) controls. Cellular mesenchymal to epithelial transition factor (c-Met) is a receptor heightened in malignant skin cancers and involved in Tpl2 signaling. When bound to its ligand, hepatocyte growth factor (HGF), c-Met can regulate cell proliferation, survival, angiogenesis and invasion. The aim of this study was to ascertain whether c-Met signaling contributes to the heightened skin tumorigenesis in Tpl2-/- mice. Forty-four WT and Tpl2 -/- mice were subjected to a two-stage chemical carcinogenesis protocol for one year to induce skin tumors. Starting at the time of promotion, half of the WT and Tpl2 -/- mice were placed on normal diet and half received diet plus 30mg/kg Capmatinib, a pharmacological inihibitor of c-Met. This diet continued for the duration of the study. No adverse health effects were found in Capmatinib-treated mice. Similar to what we previously reported, Tpl2 -/- mice developed tumors earlier than WT controls and had statistically higher tumor incidence and overall tumor burden than WT mice. The number of tumor bearing Tpl2 -/- and Tpl2 -/- + Capmatinib fed mice was similar, although Capmatinib fed mice had a 60% reduction in overall tumor burden. Studies are underway to determine if Capmatinib affected the frequency of malignant conversion in Tpl2 -/- mice. In summary, our studies demonstrate that heightened c-Met signaling contributes to the higher tumor formation in Tpl2-/- mice and should be evaluated further as a possible therapeutic target in Tpl2-related skin cancers.

Citation Format: Nicole F. Bonan, David Kowalski, Kaitlin Kudlac, Lauren G. Falkenberg, Erik Maradiaga, Kira Flaherty, Jonathan S. Wiest, Katie L. DeCicco-Skinner. Role of c-Met in the development and progression of Tpl2-related skin cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2809. doi:10.1158/1538-7445.AM2017-2809
Abstract 2811: Comparative study of anti-PD1 and CSF1R inhibition on tumor-infiltrating lymphocytes and macrophage populations across a panel of syngeneic tumor models
Authors: Maves Yuki Kato , Izadi Hooman , Talaoc Elvira C. , Yan Deborah , Echegaray Charlene , Calinisan Andrew , Moya Krystal , Venant Heather , Garland Mitchell , Iyer Radhika , Gosh Shounak , Songco Stephanie , Thatte Jayant , Broudy Tommy
Published: July 2017

Immunotherapy represents an extremely promising treatment approach for cancer patients. The success in this field has been signified by multiple recent approvals of checkpoint inhibitors across a range of cancer types. Subsequently, there is an increasing need to understand why certain patients and diseases benefit from these treatments while others do not, as well as how to maximize the benefits from these treatments.

To address some of these questions, we used an in vivo screening platform, MuScreen, which allows for evaluation of multiple syngeneic models and treatment modalities.We have characterized baseline and treated tumor immune infiltrates for a panel of syngeneic models using flow cytometry. The correlation between responsiveness and effects of checkpoint inhibitors (e.g., anti-PD-1), and macrophage targeted agents (e.g., CSF1R inhibition) on immune infiltrates including tumor-associated macrophages (TAMs) were investigated in 6 syngeneic models. Furthermore, M1/M2 polarization of macrophages was investigated to explore the potential role of these cells in establishing an immunosuppressed tumor microenvironment that may affect response to therapy.

Here, we show that the baseline immune cell population varies across models, and that immune checkpoint inhibitors and macrophage-targeted agents had variable efficacy across different tumor models. We also present the correlation of immune cell infiltration, including tumor infiltrating lymphocytes (TILs), TAMs, and responsiveness to immunotherapy intervention.

Having an in-depth understanding of the immune make up of a model in which an immunomodulatory compound is screened is paramount for successful translation into the clinic. A well-characterized and fully profiled panel of syngeneic models such as the MuScreen platform allows for finding the right model for screening test compounds to be used alone or in combination with immunotherapy.

Citation Format: Yuki Kato Maves, Hooman Izadi, Elvira C. Talaoc, Deborah Yan, Charlene Echegaray, Andrew Calinisan, Krystal Moya, Heather Venant, Mitchell Garland, Radhika Iyer, Shounak Gosh, Stephanie Songco, Jayant Thatte, Tommy Broudy. Comparative study of anti-PD1 and CSF1R inhibition on tumor-infiltrating lymphocytes and macrophage populations across a panel of syngeneic tumor models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2811. doi:10.1158/1538-7445.AM2017-2811
Abstract 2853: Imaging tumor metabolism to guide treatment of breast cancer with drugs targeted at PI3K alpha
Authors: Ros Susana , D'Santos Paula , Hu De-en , Batra Ankita S. , Wright Alan J. , Mannion Elizabeth , Bruna Alejandra , Caldas Carlos , Brindle Kevin M.
Published: July 2017

PI3KCA (which encodes the phosphoinositide-3 kinase alpha isoform) is the most frequently mutated oncogene in breast cancer. Recently, several alpha isoform-specific PI3K inhibitors have been developed and have entered into early-phase clinical trials. However, intrinsic and acquired resistance limits their utility. Non-invasive imaging methods could be used to guide treatment by not only allowing selection of the most effective drug in individual patients, but also by detecting intrinsic and acquired resistance.

We have been evaluating the effectiveness of a selective PI3K alpha inhibitor, Taselisib (GDC-0032 Genentech S.A.), by monitoring the rate of [1-13C]lactate production after injection of hyperpolarized [1-13C]pyruvate in cell lines and patient-derived xenografts (PDX) models of breast cancer using 13C magnetic resonance spectroscopic imaging. Hyperpolarization of the 13C nucleus increases its sensitivity to detection in the MR experiment by 104 - 105x, thus allowing real time imaging of tumor metabolism. Preliminary data suggest that labeled lactate production can distinguish sensitive and resistant breast cancer models to Taselisib a few days after treatment. We are currently broadening the panel of PDXs analyzed and also including genetically engineered mechanistic-models of drug resistance.

The present study highlights the effectiveness of hyperpolarized 13C spectroscopy/spectroscopic imaging for detecting early response or resistance to next generation PI3K inhibitors. This clinically applicable technique can provide insights into in vivo response in real-time and identify new strategies to increase the efficacy of therapy in individual patients.

Citation Format: Susana Ros, Paula D'Santos, De-en Hu, Ankita S. Batra, Alan J. Wright, Elizabeth Mannion, Alejandra Bruna, Carlos Caldas, Kevin M. Brindle. Imaging tumor metabolism to guide treatment of breast cancer with drugs targeted at PI3K alpha [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2853. doi:10.1158/1538-7445.AM2017-2853
Abstract 2886: CD44/SMURF1 signaling maintains cancer stem cell-like invasive cells in head and neck squamous cell carcinoma
Authors: Khammanivong Ali , Gopalakrishnan Raj , Dickerson Erin B.
Published: July 2017

Head and neck squamous cell carcinoma (HNSCC) is highly invasive and resistant to therapies, where treatments often result in high rates of failure and disease recurrence. A subpopulation of tumor-initiating cancer stem cells (CSC) is thought to be responsible for metastatic invasion and drug resistance in many types of cancer, including HNSCC. CD44 is a known CSC marker in HNSCC but its role in maintaining CSC populations is not well understood. We previously reported that SMAD specific E3 ubiquitin protein ligase 1 (SMURF1) inhibition of bone morphogenetic protein (BMP) signaling is essential for maintaining a CD44-high CSC-like population in HNSCC. In this study, we sought to determine how CD44, a receptor for hyaluronic acid (HA) that constitutes a major component of the tumor stroma, is involved in the regulation of SMURF1 and the maintenance of a HNSCC CSC phenotype. CSC-like cells were enriched from HNSCC cell lines as CD44-high cells. CD44 signaling was stimulated by exogenous HA treatment and inhibited by CD44 knockout (KO) using an inducible CRISPR/Cas9 system. We then assessed changes in SMURF1 protein level, BMP signaling, transwell migration, Matrigel colony formation, and invasion through three-dimensional organotypic culture (OTC) following CD44 modulation. CD44-high cells were found to have increased extracellular HA production. Treatment with exogenous HA reduced BMP signaling, as determined by a reduction in phospho-SMAD1/5/8 levels, and increased transwell migration of CD44-high cells. CD44-KO reduced SMURF1 protein expression and inhibited Matrigel colony formation of an invasive and recurrent HNSCC-derived CD44-high cells but only partially reduced colony formation of a less-invasive cell line derived from a primary HNSCC. Knockout of CD44 expression showed a slight reduction in transwell migration of invasive cells. CD44-high cells also recapitulated an invasive and CSC-like growth pattern in OTC assays. In contrast, CD44-KO inhibited OTC invasion and the epithelial-to-mesenchymal transition (EMT) phenotype, resulting in increased apical epithelial growth and differentiation. CD44 reconstitution appeared to restore the invasive and EMT phenotype. Based on our current findings, CD44 may be crucial for maintaining an anchorage-independent and invasive phenotype of HNSCC but plays a minor role in carcinoma cell migration.

Citation Format: Ali Khammanivong, Raj Gopalakrishnan, Erin B. Dickerson. CD44/SMURF1 signaling maintains cancer stem cell-like invasive cells in head and neck squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2886. doi:10.1158/1538-7445.AM2017-2886
Abstract 290: A novel function of HGF in the activation of Chk1 phosphorylation in colon cancer cells
Authors: Song Na , Che Xiaofang , Qu Xiujuan , Xu Lu , Hou Kezuo , Liu Yunpeng
Published: July 2017

ATR/Chk1 pathway plays an essential role in modulation of DNA damage response (DDR) and homologous recombination (HR). Particularly, Chk1 phosphorylation is involved in cancer prognosis and therapeutic resistance. Although some receptor tyrosine kinases (RTKs) participate in the regulation of Chk1 phosphorylation, the effect of hepatocyte growth factor (HGF) on Chk1 phosphorylation is unknown. In the present study, Western blotting and subcellular fractionation were performed to identify the expression and the location of Chk1 phosphorylation in the presence of HGF. With small interfering RNA transfections, co-immunoprecipitations were performed to detect the interaction between TopBP1 and ATR complex. Our results demonstrated that HGF moderately activated Chk1 phosphorylation in colon cancer cells via upregulation of TopBP1, RAD51, and complex formation of TopBP1 and ATR. Furthermore, AKT activation promoted by HGF served as an important intermediator linking HGF/MET signaling and Chk1 phosphorylation. Depletion of AKT activity attenuated expression of basal line p-Chk1 and induced Chk1 activation due to HGF stimulation. Meantime, activation of AKT directly regulated expression of TopBP1 and RAD51. Suppression of AKT restored HGF-induced upregulation of TopBP1, RAD51, and enhancement of TopBP1/ATR complex as well. Our studies showed that HGF was implicated in regulating Chk1 phosphorylation and further demonstrated that AKT activity was responsible for HGF-induced Chk1 phosphorylation, which might potentially result in management of prognosis and therapeutic sensitivity in cancer therapy.

Note: This abstract was not presented at the meeting.

Citation Format: Na Song, Xiaofang Che, Xiujuan Qu, Lu Xu, Kezuo Hou, Yunpeng Liu. A novel function of HGF in the activation of Chk1 phosphorylation in colon cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 290. doi:10.1158/1538-7445.AM2017-290
Abstract 2940: TH17: mediators of metastatic growth acceleration after surgery
Authors: Sud Vikas , Tohme Samer , Windt Dirk J. van der , Huang Hai , Tsung Allan
Published: July 2017

Surgery is known to accelerate the growth and progression of metastases in patients undergoing oncological resections with 50-60% patients having recurrent metastasis after resection making it a major reason for treatment failure. This impedes the efficacy of adjuvant chemotherapy and overall prognosis of the patient. Studies have proved that inflammatory cascade initiated by surgery that increases metastatic growth and progression is mediated through a specific mechanism of neutrophil cell death called Neutrophil Extracellular Traps (NETs). We investigated the mechanism of how NET formation after surgical stress increases metastatic growth by influencing a pro-tumor microenvironment in order to specifically identify targets for perioperative therapy to keep metastases dormant and improve the effect of chemotherapy and overall prognosis. 12 week old male C57BL/6J mice (WT) and mice in which NET formation was inhibited, ie, WT mice injected with DNAse and global homozygous knockout of peptidyl arginine deaminase 4 (PAD4), an essential nuclear protein for NET formation, underwent splenic injection of 100,000 cells of the murine colorectal cancer cell line, MC-38, followed with either 70% hepatic ischemia-reperfusion (IR) for 60 minutes after 7 days or no IR. Livers were harvested at multiple time points and assessed for changes in both innate and adaptive immune cell populations by flow cytometry. On gross examination, the livers of the NET deficient mice had fewer tumors as compared to the WT mice. Mice, which underwent IR after tumor cell injection in both groups showed an increase in nodules formation versus those with just tumor cell injection, however were still more in WT than NET deficient mice. Flow cytometry revealed a decrease in both TH17 (0.36% of T cells in no IR mice vs 0.0036% in IR mice) and CD8 cells (71% of T cells in no IR mice vs 34.8% in IR mice) in mice subjected to IR versus those with only tumor injection. We found that increased tumors after surgical stress, which were mediated by NET formation, were caused due to a decrease in anti-tumor activity of CD8 cells regulated via TH17 cells. If controlled in the perioperative period, it may reduce acceleration in metastatic foci and improve the overall prognosis. We are further investigating the mechanism of NETs influencing the tumor immune environment.

Citation Format: Vikas Sud, Samer Tohme, Dirk J. van der Windt, Hai Huang, Allan Tsung. TH17: mediators of metastatic growth acceleration after surgery [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2940. doi:10.1158/1538-7445.AM2017-2940
Abstract 2956: Chemical library screen identifies compounds that target S100A8/S100A9 complex and MDSC accumulation
Authors: Lee Eunmi , Ouzounova Maria , Piranlioglu Raziye , Andaloussi Abdeljabar El , Arbag Sena , Zhou Gang , Korkaya Hasan
Published: July 2017

We previously demonstrated that MDSC subsets accumulated in primary tumor and distant organs regulate tumor plasticity. The mouse transcriptome analysis of in vitro co-cultures and samples from syngeneic mouse model revealed that granulocytic subset of myeloid-derived suppressor cells (gMDSCs) from metastatic 4T1 tumor bearing mice regulate several hundred genes in tumor cells upon co-culture. The top genes are S100A8, S100A9, MMP8, FPR1, CCL3, and TGFβ2 which also predicted poor survival in human solid tumors including breast cancer. Therefore, we called these 6 genes as “metastatic gene signature”. It has been reported that S100A8/S100A9 heterotetramer, called calprotectin, play a key role in inflammation-associated cancer progression. To investigate the role of calprotectin (S100A8/A9) in tumor-mediated immunosuppression and metastasis, we first utilized Tasquinimod, a small molecule targeting S100A9 only. However, Tasquinimod treatment of 4T1 tumor-bearing mice had a moderate anti-tumor activity which may be due to a limited activity on granulocytic MDSC accumulation. In addition, we determined that there was a significant upregulation of S100A8 in MDSCs from Tasquinimod treated mice. This data suggested that inhibiting only S100A9 leads to activation of S100A8 and thus may be ineffective targeting of MDSCs. We therefore run a computational screen of the NCI chemical library against the crystal structure of calprotectin (S100A8/S100A9) and identified 40 lead compounds. We then performed in vitro screening assay to identify compounds that inhibit MDSC induction. We identified 3 compounds that significantly suppressed gMDSC differentiation. We are currently performing in vivo studies with these 3 candidate drugs in our murine breast cancer model and will present our findings at the AACR meeting. We believe that this study will provide a novel drug targeting S100A8/S100A9 heterotetramer, a key molecule in MDSC induction and its regulatory functions during tumor progression.

Citation Format: Eunmi Lee, Maria Ouzounova, Raziye Piranlioglu, Abdeljabar El Andaloussi, Sena Arbag, Gang Zhou, Hasan Korkaya. Chemical library screen identifies compounds that target S100A8/S100A9 complex and MDSC accumulation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2956. doi:10.1158/1538-7445.AM2017-2956
Abstract 2960: Adipocytes sequester and metabolize daunorubicin
Authors: Sheng Xia , Parmentier Jean-Hugues , Tucci Jonathan , Pei Hua , Cortez-Toledo Omar , Dieli-Conwright Christina , Oberley Matthew , Neely Michael , Orgel Etan , Louie Stan , Mittelman Steven D.
Published: July 2017

Obesity is associated with poorer outcome from many cancers, including childhood acute lymphoblastic leukemia (ALL). We have previously shown that adipocytes protect ALL cells from the anthracycline, daunorubicin (DNR). We therefore investigated whether adipocytes sequester and/or metabolize DNR in the ALL microenvironment. Using fluorescence and LC/MS measures, we demonstrated that adipocytes absorb DNR, reducing the intracellular DNR concentration in co-cultured BV173 ALL cells (after 48 hours, median fluorescent intensity of ALL cultured with adipocytes was 1.7±1.0 vs. 5.0±1.7 of those cultured alone, p<0.01). Mouse adipocytes convert DNR to the less active metabolite, daunorubicinol (DNR-ol); over 48 hours, media DNR decreased to 0.1±0.2 (vs. 24.8±8.76 ng/mL in control wells). At the same time, DNR-ol increased to 15.0±1.9 (vs. 0.7±0.6 in control wells; both p<0.05). Similar conversion of DNR to DNR-ol was observed in both mouse adipose explants and human adipose tissue biopsy samples ex vivo. qPCR confirmed human subcutaneous adipose tissue expresses several enzymes capable of metabolizing DNR, including AKR1A1, 1B1, 1C1, 1C2, 1C3, 7A2, and CBR1 and 3 (expression ranged between 20 and 195% β-actin). Using immunohistochemistry, we confirmed expression of AKR1C1, 1C2, and 1C3 in bone marrow adipocytes of children during the first month of treatment for ALL. Finally, two hours after an intravenous dose of DNR in mice, we found that the DNR-ol to DNR ratio was higher in subcutaneous (0.60±0.26) and omental (0.55±0.21) adipose than in white blood cells (0.16±0.11), bone marrow (undetectable DNR-ol), and spleen (undetectable DNR-ol). Together, these data demonstrate that adipocytes sequester and inactivate DNR, likely due to their expression of AKR and CBR enzymes. These findings uncover a novel and important mechanism which could promote local anthracycline resistance by cancer cells in microenvironment rich in adipocytes, such as bone marrow, omentum, and breast.

Citation Format: Xia Sheng, Jean-Hugues Parmentier, Jonathan Tucci, Hua Pei, Omar Cortez-Toledo, Christina Dieli-Conwright, Matthew Oberley, Michael Neely, Etan Orgel, Stan Louie, Steven D. Mittelman. Adipocytes sequester and metabolize daunorubicin [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2960. doi:10.1158/1538-7445.AM2017-2960