SITC 2017 Abstract Titles – Tumor Microenvironment (Mechanisms and Therapies)

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Authors

Affiliations

Keywords

P451

Alpha-TEA demonstrates antitumor activity against trastuzumab sensitive and resistant breast cancer

Emmanuel Akporiaye¹, Mary Disis², Ekram Gad², Tobias Hahn¹, Brook Cole³, Michael Gough¹, Talicia Savage⁴, Hailing Lu⁵

1Providence Portland Medical Center, Portland, OR, USA ²University of Washington School of Medicine, Seattle, WA, USA ³University of Minnesota, Minneapolis, MN, USA ⁴Albert Einstein College of Medicine, Bronx, NY, USA ⁵Immune Design, Seattle, WA, USA

Tumor microenvironment | Immune adjuvant | Antibody | Solid tumors

P452

Defining IL-15 expressing myeloid cells in the tumor microenvironment

Figen Beceren-Braun¹, Rosa M. Santana Carrero¹, Sarai C. Rivas¹, Kimberly S. Schluns¹

1University of Texas MD Anderson Cancer Center, Houston, TX, USA

Tumor microenvironment | Monocyte/Macrophage | Cytokine | Gene expression | Inflammation

P453

Targeted tumor stroma depletion in combination with a whole cell tumor vaccine enhances effector T cell infiltration in a mouse model of pancreatic cancer

Alex Blair¹, Victoria Kim¹, Stephen Muth¹, Todd Armstrong¹, Sanna Rosengren², Lei Zheng¹

1Johns Hopkins Medical Institution, Baltimore, MD, USA ²Halozyme Therapeutics, San Diego, CA, USA

Tumor microenvironment | Gene expression | Monocyte/Macrophage | T cell | Solid tumors | Tumor stroma | Vaccine | Tumor infiltrating lymphocytes (TILs)

P454

Molecular targeted radiotherapy facilitates in situ vaccination in a syngeneic murine melanoma model

Peter M Carlson¹, Clinton Heinze¹, Joseph Grudzinski¹, Reinier Hernandez¹, Stephen D Gillies², Hans Loibner³, Alexander L Rakhmilevich¹, Mario Otto¹, Bryan Bednarz¹, Jamey Weichert¹, Paul M Sondel¹, Zachary S Morris¹

1University of Wisconsin School of Medicine and Public Health, Madison, WI, USA ²Provenance Biopharmaceuticals, Carlisle, MA, USA ³Apeiron Biologics, Vienna, Austria

Regulatory T cell (Treg) | Tumor microenvironment | Targeted therapy | Immune suppression | Vaccine | T cell

P455

Investigating the specificity and response of a native leukemia-reactive CD8+ T cell clone

Xiufen Chen¹, Brendan MacNabb¹, Emily Curran¹, Bruce Blazar², Justin Kline¹

1University of Chicago, Chicago, IL, USA ²University of Minnesota, Minneapolis, MN, USA

Antigen presenting cells | Immune tolerance | Tumor microenvironment | Leukemia/Lymphoma | Tumor infiltrating lymphocytes (TILs) | Checkpoint blockade

P456

CDK4 & 6 inhibitor Abemaciclib exerts intrinsic immunomodulatory effects on human T cells in vitro

Darin Chin¹, Carmine Carpenito¹, Nelusha Amaladas¹, Linda Chung², Kirk Staschke², David Schaer³, Richard Beckmann², Ruslan Novosiadly¹, Michael Kalos¹

1Eli Lilly & Co, New York, NY, USA ²Eli Lilly & Co, Indianapolis, IN, USA ³Eli Lilly & Co, Brooklyn, NY, USA

Biomarkers | Checkpoint blockade | Gene expression | Immune toxicity | Immune tolerance | Costimulation

P457

Pharmacodynamic activity of MEDI9197, a TLR7/8 agonist, administered intratumorally in subjects with solid subcutaneous or cutaneous tumors

Zachary A. Cooper¹, Christopher A. Morehouse¹, Yuling Wu¹, Keith Steele¹, David Brucker², Leo Tseng¹, Maria Jure-Kunkel¹, Nancy Mueller¹, Patricia Ryan¹, Juneko Grilley-Olson³, David Hong⁴, Aurélien Marabelle⁵, Pamela Munster⁶, Rahul Aggarwal⁶, Sandrine Aspeslagh⁵, Robert G. Dixon³, Manish Patel⁷, Vivek Subbiah⁴, Joshua Brody⁸, Shilpa Gupta⁷

1MedImmune, Gaithersburg, MD, USA ²Definiens, Cambridge, MA, USA ³University of North Carolina Lineberger Comprehensive Cancer Center, Chapel Hill, NC, USA ⁴MD Anderson Cancer Center, Houston, TX, USA ⁵Institut Gustave Roussy, 94800 Villejuif, France ⁶UCSF Helen Diller Family Comprehensive Cancer Center, San Francisco, CA, USA ⁷Masonic Cancer Center, Minneapolis, MN, USA ⁸Mount Sinai (Hess Center for Science and Medicine), New York, NY, USA

TLR | Inflammation | Checkpoint blockade | MDSC | Chemokine | Cytokine | T cell | Dendritic cell

P458

Nitric oxide synthase inhibition results in PDL-1 upregulation and ADAR1 inhibition, triggering immunogenic cell death: an in-vitro and in-vivo analysis

Daniel Davila-Gonzalez¹, Roberto Rosato¹, Wei Qian¹, Anthony Kozielski¹, Wen Chen¹, Dong Soon Choi¹, Patrick Tucker¹, Jenny Chang¹

1Houston Methodist, Houston, TX, USA

Adoptive immunotherapy | Tumor microenvironment | Checkpoint blockade | Targeted therapy | Antibody | Cytokine | Immune suppression | T cell

P459

Class IIa HDAC inhibition promotes an anti-tumor macrophage phenotype that induces breast tumor regression and inhibits metastasis

Jennifer Guerriero¹, Alaba Sotayo¹, Holly Ponichtera¹, Jessica Castrillon¹, Alexandra Pourzia¹, Sara Schad¹, Shawn Johnson¹, Ruben Carrasco¹, Suzan Lazo¹, Roderick Bronson², Scott Davis³, Mercedes Lobera³, Michael Nolan³, Anthony Letai¹

1Dana-Farber Cancer Institute, Boston, MA, USA ²Harvard Medical School, Boston, MA, USA ³GlaxoSmithKline, Cambridge, MA, USA

Antigen presenting cells | Costimulation | Myeloid cells | Tumor microenvironment | Monocyte/Macrophage | Solid tumors

P460

Selenium, the element of the moon, improves immunotherapies on earth

Claudia Lennicke¹, Shamim Ahmad¹, Rajeev Shrimali¹, Barbara Seliger², Youcef Rustum³, John Janik¹, Mikayel Mkrtichyan¹, Seema Gupta¹, Samir Khleif¹

1Augusta University, Augsuta, GA, USA ²Institute of Medical Immunology, Halle, Germany ³University of Buffalo, Buffalo, NY, USA

Tumor microenvironment | Regulatory T cell (Treg) | Vaccine | Tumor evasion | Tumor infiltrating lymphocytes (TILs) | T cell | Solid tumors | Immune suppression | Tumor antigens

P461

Listeria monocytogenes-based immunotherapies alter the suppressive phenotype of intratumoral regulatory T cells

Rachelle E. Kosoff¹, Nithya Thambi¹, Lauren K. Pettit¹, Daniel O. Villarreal¹, Kimberly Ramos¹, Michael F. Princiotta¹, Robert G. Petit¹, Sandra M. Hayes¹

1Advaxis, Inc., Princeton, NJ, USA

Tumor microenvironment | Regulatory T cell (Treg) | Tumor infiltrating lymphocytes (TILs) | Vaccine | Immune monitoring | Gene expression

P462

Ubiquitin-specific Protease 6 (USP6) Oncogene Promotes Immune Cell Recruitment in Sarcoma

Ian Henrich¹, Laura Quick², Rob Young², Andre Oliveira³, Margaret Chou¹

1University of Pennsylvania, Philadelphia, PA, USA ²Children's Hospital of Pennsylvania, Philadelphia, PA, USA ³Mayo Clinic, Rochester, MN, USA

Carcinogenesis | Pediatric tumors | Tumor microenvironment | Chemokine | Cytokine | Solid tumors

P463

TAM RTKs Facilitate MDSC-mediated Tumor Immunosuppression

Alisha Holtzhausen¹, William Harris¹, Debra Hunter¹, Eric Ubil¹, Xiaodong Wang¹, Douglas Graham², Stephen Frye¹, H. Shelton Earp¹

1University of North Carolina at Chapel Hill, Chapel Hill, NC, USA ²Emory University, Atlanta, GA, USA

Immune tolerance | Myeloid cells | Tumor microenvironment | MDSC

P464

Use of evofosfamide for targeting immune-suppressive hypoxia in head and neck squamous cell carcinoma

Francis Hunter¹, Avik Shome¹, Way Wong¹, Pratha Budhani², Neil Senzer³, E. Gabriela Chiorean⁴, Dan Li¹, Peter Tsai¹, Nooriyah Poonawala¹, Purvi Kakadiya¹, Maria Kondratyev⁵, Courtney Lynch¹, Cho Rong Hong¹, Tet-Woo Lee¹, Dennis Kee⁶, Andrew Macann⁶, Nicholas McIvor⁶, Kevin Hicks¹, Stefan Bohlander¹, Cristin Print¹, Stew Kroll⁷, Charles Hart⁷, Bradly Wouters⁵, William Wilson¹, Michael Curran², Stephen Jamieson¹

1University of Auckland, Auckland, New Zealand ²MD Anderson Cancer Center, Houston, TX, USA ³Mary Crowley Cancer Research Center, Dallas, TX, USA ⁴Indiana University Melvin and Bren Simon Cancer Center, Indianapolis, IN, USA ⁵University Health Network, Toronto, ON, Canada ⁶Auckland City Hospital, Auckland, New Zealand ⁷Threshold Pharmaceuticals, San Francisco, CA, USA

Tumor microenvironment | Biomarkers | Checkpoint blockade | Targeted therapy | Solid tumors | Radiotherapy | Immune suppression | Clinical trial

P465

Characterization of immune cells in the pre-metastatic niche in a murine model of rhabdomyosarcoma

Sabina Kaczanowska¹, Meera Murgai¹, Daniel Beury¹, Rosandra Kaplan¹

1National Cancer Institute, Bethesda, MD, USA

Pediatric tumors | Tumor microenvironment | Immune contexture

P466

Rational Design of Immuno-Oncology Biologics with Improved Safety and Efficacy

Margaret Karow¹, Kurt Jenkins², Miso Park², Parker Johnson², Asaul Gonzalez², Veronica Flesch², Tim Miles², Ulrich Rodeck³, John Williams²

1Akriveia Therapeutics, Thousand Oaks, CA, USA ²City of Hope, Duarte, CA, USA ³Thomas Jefferson University, Philadelphia, PA, USA

Regulatory T cell (Treg) | Tumor microenvironment | Autoimmunity | Checkpoint blockade | Immune toxicity | Targeted therapy | Antibody | T cell | Tumor infiltrating lymphocytes (TILs) | Solid tumors

P467

CCR4 antagonists inhibit regulatory T cell (Treg) recruitment and increase effector T cell (T_eff) numbers in the tumor microenvironment potentiating an anti-tumor response

Oezcan Talay¹, Lisa Marshall¹, Cesar Meleza¹, Maureen Reilly¹, Omar Robles¹, Mikhail Zibinsky¹, Abood Okal¹, Jenny McKinnell¹, Scott Jacobson¹, Erin Riegler², Sashie Marubayashi¹, Emily Karbarz¹, David Chian¹, Angela Wadsworth¹, David Wustrow¹, Jordan Fridman², Paul Kassner¹

1FLX Bio Inc., South San Francisco, CA, USA ²Formerly at FLX Bio Inc., South San Francisco, CA, USA

Chemokine | Tumor microenvironment | Regulatory T cell (Treg) | Immune contexture | Checkpoint blockade | T cell | Tumor infiltrating lymphocytes (TILs) | Immune suppression

P468

A novel 3D ex vivo platform of fresh patient tumor tissue with intact tumor microenvironment for immuno-oncology drug development and biomarker discovery

Melanie Mediavilla-Varela¹, Melba Marie Page¹, Jenny Kreahling¹, Scott Antonia¹, Soner Altiok¹

1Nilogen Oncosystems, Tampa, FL, USA

Biomarkers | Checkpoint blockade | Cytokine | Chemokine | Tumor microenvironment | Targeted therapy | Solid tumors | Tumor infiltrating lymphocytes (TILs) | Monocyte/Macrophage | T cell

P469

Tumor oxygenator OMX reverses multiple modes of immunosuppression, activates anti-tumor immunity and cures as a single agent, and in combination with anti-PD-1 in resistant orthotopic tumors

Ana Krtolica¹, Natacha Le Moan¹, Philberta Leung¹, Sarah Ng¹, Tina Davis¹, Carol Liang¹, Jonathan Winger¹, Stephen P. L. Cary¹

1Omniox, Inc., San Carlos, CA, USA

Tumor microenvironment | Tumor stroma | Tumor infiltrating lymphocytes (TILs) | Solid tumors | Immune suppression | Checkpoint blockade | Angiogenesis | Regulatory T cell (Treg) | Cytokine | Chemokine

P470

Tertiary lymphoid organs as a good prognostic indicator following neoadjuvant chemo (radio) therapy for pancreatic cancer

Shota Kuwabara¹, Takahiro Tsuchikawa¹, Yoshitsugu Nakanishi¹, Toshimichi Asano¹, Takehiro Noji¹, Yo Kurashima¹, Yuma Ebihara¹, Soichi Murakami¹, Toru Nakamura¹, Keisuke Okamura¹, Toshiaki Shichinohe¹, Satoshi Hirano¹

1Hokkaido University Graduate School of Medicine, Sapporo Hokkaido, Japan

Biomarkers | Chemotherapy | Tumor microenvironment | Surgery | Solid tumors

P471

Patterns of immune cell infiltration in murine models of melanoma: roles of antigen and tissue site in creating inflamed tumors

Katie Leick¹, Joel Pinczewski², Donna Deacon¹, Amber Woods¹, Marcus Bosenberg³, Victor Engelhard¹, Craig Slingluff¹

1University of Virginia, Charlottesville, VA, USA ²Dorevitch Pathology, North Melbourne, Australia ³Yale University, New Haven, CT, USA

Tumor antigens | Tumor infiltrating lymphocytes (TILs) | Immunoscore | Neoantigens | Solid tumors | Tumor microenvironment

P472

DARPin®-based fibroblast activation protein-targeted agonists of 4-1BB and OX40 co-stimulate T-cells in a Fc-receptor-independent, tumor-restricted manner

Alexander Link¹, Julia Hepp¹, Ulrike Fiedler¹, Christian Reichen¹, Clara Metz¹, Alexander Titz¹, Ivana Tosevski¹, Joanna Taylor¹, Zita Arany¹, Laurent Juglair¹, Patricia Schildknecht¹, Yvonne Kaufmann¹, Denis Villemagne¹, Simon Fontane¹, Ralph Bessey¹, Christof Zitt¹, Keith Dawson¹, Dan Snell¹, Daniel Steiner¹, Michael Stumpp¹, Victor Levitsky¹

1Molecular Partners AG, Schlieren-Zürich, Switzerland

Costimulation | Immune toxicity | Targeted therapy | Tumor stroma | Immune suppression | Tumor infiltrating lymphocytes (TILs)

P473

Immuno-oncological efficacy of RXDX-106, a novel TAM (TYRO3, AXL, MER) family small molecule kinase inhibitor

Erin Lew¹, Yumi Yokoyama¹, Colin Walsh¹, Jack Lee¹, Joanne Oh¹, Elizabeth Tindall¹, Robin Navarez¹, Amy Dilberto¹, Heather Ely¹, Ruth Seelige², Amanda Albert¹, Jack Bui², Gary Li¹

1Ignyta, Inc, San Diego, CA, USA ²University of California, San Diego, San Diego, CA, USA

Tumor microenvironment | Monocyte/Macrophage | T cell | Tumor infiltrating lymphocytes (TILs) | Targeted therapy

P474

Gene Expression in MHC II Pathway May Predict Triple Negative Breast Cancer Prognosis

Amy Zhao¹, Gavin Bond¹, Katherine Varley², Andres Forero-Torres³, Albert LoBuglio³, Dongquan Chen³

1University of Pennsylvania, Philadelphia, PA, USA ²University of Utah, Salt Lake City, UT, USA ³University of Alabama at Birmingham, Birmingham, AL, USA

Bioinformatics | Biomarkers | Tumor microenvironment | Gene expression | T cell | Tumor infiltrating lymphocytes (TILs) | Antigen presenting cells

P475

Profiling Immune Infiltration of Glioblastoma

Camilo Fadul¹, Craig Slingluff¹, Ileana Mauldin¹

1University of Virginia, Charlottesville, VA, USA

Tumor microenvironment | Tumor infiltrating lymphocytes (TILs) | Biomarkers | Immune tolerance

P476

Targeting the IDO/TDO Pathway through Degradation of the Immunosuppressive Metabolite Kynurenine and Inhibition of the Downstream AHR Pathway

Karen McGovern¹, X. Michelle Zhang¹, Everett Stone³, Todd Triplett³, Kendra Garrison³, Silvia Coma¹, Luis Felipe Campesato², Meghan Walsh¹, Jeremy Tchaicha¹, Candice Lamb³, Christos Karamitros³, John Blazek³, Taha Merghoub², Jedd Wolchok², George Georgiou³, Mark Manfredi¹

1Kyn Therapeutics, Cambridge, MA, USA ²Memorial Sloan Kettering Cancer Center, New York, NY, USA ³University of Texas, Austin, TX, USA

Immune suppression | Metabolism | Tumor microenvironment | Tumor infiltrating lymphocytes (TILs) | T cell | Checkpoint blockade | Gene expression

P477

Novel effector phenotype of Tim3+ regulatory T cells leads to enhanced suppressive function in head and neck cancer patients

Zhuqing Liu¹, Elizabeth McMichael², Gulidanna Shayan³, Jing Li³, Rghvendra Srivastava², Lawrence Kane², Robert Ferris²

1Tongji University, Shanghai, China ²University of Pittsburgh, Pittsburgh, PA, USA ³Tsinghua University, Beijing, China

Tumor microenvironment | T cell | Immune suppression

P478

Formation and functional associations of CD49a-, CD49b- and CD103-expressing CD8 T cell populations in human metastatic melanoma

Marit Melssen¹, Walter Olson¹, Nolan Wages¹, Ciara Hutchison¹, Ileana Mauldin¹, Cornelis Melief², Timothy Bullock¹, Victor Engelhard¹, Craig Slingluff, Jr¹

1University of Virginia, Charlottesville, VA, USA ²ISA Pharmaceuticals, Leiden, Netherlands

Tumor infiltrating lymphocytes (TILs) | Tumor microenvironment | T cell lineages | Tumor stroma | Cytokine | T cell | Solid tumors

P479

MPL-5821, an ESM™-p38 MAPK Inhibitor, modulates macrophage plasticity leading to enhanced IL-12p70 and IFN gamma, reduced IL-10 and the reversal of macrophage induced T-cell suppression.

Martin Perry¹, David Moffat¹, Justyna Rzepecka², Lucia Janicova², Anastasia Nika², Darryl Turner², Clare Doris², Stephen Anderton²

1Macrophage Pharma Limited, Windsor, United Kingdom ²Aquila BioMedical Limited, Edinburgh, United Kingdom

Antigen presenting cells | Myeloid cells | Tumor microenvironment | Targeted therapy | Chemokine | Cytokine | Immune suppression | Monocyte/Macrophage | T cell | Inflammation

P480

Tumor infiltrating T regulatory cells in head and neck cancer patients treated with cetuximab demonstrate increased inhibitory receptors and survival.

Jessica Moskovitz¹, Tullia Bruno¹, Robert Ferris¹, Dario Vignali¹

1University of Pittsburgh, Pittsburgh, PA, USA

Immune tolerance | Tumor microenvironment | Tumor evasion | Tumor infiltrating lymphocytes (TILs) | T cell | Solid tumors | Regulatory T cell (Treg) | Surgery

P481

Non-oncogenic Acute Viral Infection Modulates the Innate Immune Response and Reduces Tumor Growth in Hosts with Established Cancer

Jenna Newman¹, Charles Brent Chesson¹, Andrew Zloza¹

1Rutgers Cancer Institute of New Jersey, New Brunswick, NJ, USA

MDSC | Tumor microenvironment | Solid tumors | Inflammation

P482

Somatic TP53 mutations alter the immune micro-environment after chemotherapy in breast cancer

Mellissa Nixon¹, M. Valeria Estrada², Susan Opalenik¹, Donna Hicks³, Michael Korrer¹, Mark Pilkinton¹, Melinda Sanders¹, Roberto Salgado⁴, Simon Mallal¹, Young Kim¹, Rebecca Cook³, Carlos Arteaga¹, Justin Balko¹

1Vanderbilt University Medical Center, Nashville, TN, USA ²UC San Diego, La Jolla, CA, USA ³Vanderbilt University, Nashville, TN, USA ⁴Institut Jules Bordet, Brussels, Belgium

Bioinformatics | Chemotherapy | Biomarkers | Chemokine | Gene expression | Solid tumors | Tumor infiltrating lymphocytes (TILs) | Tumor microenvironment | Cytokine | T cell

P483

A novel non-competitive and non-brain penetrant adenosine A_2A receptor antagonist designed to reverse adenosine-mediated suppression of anti-tumor immunity

Erica Houthuys¹, Reece Marillier¹, Théo Deregnaucourt¹, Margreet Brouwer¹, Romain Pirson¹, Joao Marchante¹, Paola Basilico¹, Shruthi Prasad¹, Julie Preillon¹, Anne-Catherine Michaux¹, Kim Frederix¹, Annelise Hermant¹, Florence Nyawouame¹, Charlotte Moulin¹, Vanesa Bol¹, Bruno Gomes¹, Florence Lambolez¹, Véronique Bodo¹, Jakub Swiercz¹, Gregory Driessens¹, Noémie Wald¹, Chiara Martinoli¹, Michel Detheux¹, Christophe Quéva¹, Stefano Crosignani¹

1iTeos Therapeutics, Gosselies, Belgium

Tumor microenvironment | Immune suppression | Tumor infiltrating lymphocytes (TILs) | Tumor evasion

P484

A novel metabolic therapeutic that harnesses the anti-tumor immune response

Dayana Rivadeneira¹, Nicole Scharping¹, Greg Delgoffe¹

1University of Pittsburgh, Pittsburgh, PA, USA

T cell | Tumor microenvironment | Immune suppression | Metabolism | Tumor infiltrating lymphocytes (TILs)

P485

Use of the NanoString Gene Expression Profiling Platform to Capture the Immunological Status of the Leukemia Microenvironment

Jayakumar Vadakekolathu¹, Tasleema Patel², Stephen Reeder¹, Heidi Schaarschmidt³, Marc Schmitz⁴, Martin Bornhäuser³, Sarah Warren⁵, Tressa Hood⁵, Patrick Danaher⁵, Alessandra Cesano⁵, Joseph M. Beechem⁵, A. Graham Pockley¹, Sarah Tasian², Sergio Rutella¹

1Nottingham Trent University, Nottingham, United Kingdom ²Children's Hospital of Philadelphia, Philadelphia, PA, USA ³University Hospital Carl Gustav Carus, Dresden, Germany ⁴Medical Faculty Carl Gustav Carus, Dresden, Germany ⁵NanoString Technologies, Inc., Seattle, WA, USA

Immune monitoring | Immune contexture | Immune tolerance | Inflammation | Pediatric tumors | Tumor microenvironment | Biomarkers | Leukemia/Lymphoma

P486

Utilization of dual IHC and quantitative image analysis techniques to evaluate LAG-3-positive T cells in the tumor microenvironment of NSCLC tissue

Malik Khenkhar¹, Philipp Uhlig¹, Nickels Winkler¹, Hartmut Juhl¹, Alison Bigley², Lorcan Sherry²

1Indivumed GmbH, Hamburg, Germany ²OracleBio Limited, Glasgow, United Kingdom

Immune contexture | Tumor microenvironment | Checkpoint blockade | Tumor stroma | Tumor infiltrating lymphocytes (TILs) | T cell | Biomarkers | Targeted therapy | Immune tolerance | Immune monitoring

P487

Multiplex immunofluorescence evaluation of an immune cell marker panel in the tumor microenvironment of NSCLC tissue using tailored analysis of multi-spectral image component data

Richard Bystry¹, Edward Durley¹, Lee Dawson¹, Rebecca Houliston¹, Alison Bigley², Lorcan Sherry²

1Asterand Bioscience, Royston, United Kingdom ²OracleBio Limited, Glasgow, United Kingdom

Inflammation | Tumor microenvironment | Immune contexture | Biomarkers | Immune monitoring | Tumor stroma | Tumor infiltrating lymphocytes (TILs) | T cell | Regulatory T cell (Treg) | T cell lineages

P488

Single-cell RNA sequencing of CD8+ T cells to prioritize immunotherapy combinations

Yashaswi Shrestha¹, Michael Kuziora¹, Lydia Greenlees¹, Brandon Higgs¹, Katie Streicher¹, Rajiv Raja¹, Koustubh Ranade¹

1MedImmune, Gaithersburg, MD, USA

Inflammation | Checkpoint blockade | Chemokine | Cytokine | T cell | Targeted therapy | Biomarkers

P489

Studying the cellular heterogeneity and spatial arrangement of immune cells in FFPE sections of Hodgkin Lymphoma and normal lymph node using a highly multiplexed Imaging Mass Cytometry

Mohan Singh¹, Parvesh Chaudhry¹, Erik Gerdtsson¹, Lisa Harton¹, James Hicks¹, Peter Kuhn¹, Wendy Cozen¹, Imran Siddiqi¹, Akil Merchant¹

1University of Southern California, Los Angeles, Los Angeles, CA, USA

Tumor microenvironment | Regulatory T cell (Treg) | Proteomics | T cell | B cell | Tumor infiltrating lymphocytes (TILs)

P490

PSMA-specific CARTyrin T-Stem Cell Memory Therapy Eliminates Solid Tumor in Subcutaneous Prostate Cancer Model

Jenessa B. Smith¹, Rebecca Codde¹, Yening Tan¹, Burton E. Barnett¹, David Hermanson¹, Srinivas Rengarajan¹, Eric M. Ostertag¹, Devon J. Shedlock¹

1Poseida Therapeutics, San Diego, CA, USA

Adoptive immunotherapy | T cell lineages | Tumor microenvironment | Targeted therapy | Tumor antigens | T cell | Solid tumors | CAR T cells

P491

Alerting the immune system by removing epigenetic silencing of T_H1 chemokines

Heather Sonnemann¹, Amber Giles¹, Jinkyu Jung¹, Caitlin Reid¹, Marsha-Kay Hutchinson¹, Deric Park¹, Mark Gilbert¹

1NIH, NCI, Bethesda, MD, USA

Tumor infiltrating lymphocytes (TILs) | Cytokine | Tumor microenvironment

P492

Galectin-3 inhibition with GR-MD-02 synergizes with agonist anti-OX40 mAb therapy leading to reduced immune suppression and improved overall survival

Elizabeth Sturgill¹, Stephanie Linch¹, Courtney Mick¹, Melissa Kasiewicz¹, William Redmond¹

1Providence Portland Medical Center, Portland, OR, USA

Myeloid cells | Costimulation | Tumor microenvironment | MDSC | Tumor infiltrating lymphocytes (TILs) | Solid tumors | Immune suppression | T cell

P493

LTX-315: A first-in-class oncolytic peptide that reshapes the tumor microenvironment

Baldur Sveinbjørnsson¹, Ketil Camilio², Meng-Yui Wang², Janne Nestvold³, Gunhild Mælandsmo², Gunnar Kvalheim², Øystein Rekdal¹

1Lytix Biopharma, Oslo, Norway ²Radiumhospitalet, Oslo, Norway ³Rikshospitalet, Oslo, Norway

Chemotherapy | Tumor microenvironment | Checkpoint blockade | Tumor antigens | Chemokine | Tumor infiltrating lymphocytes (TILs)

P494

Reversal of Adenosine-Mediated Immune Suppression by AB421, a Potent and Selective Small-Molecule CD73 Inhibitor

Joanne BL Tan¹, Annette Becker¹, Daniel DiRenzo¹, Kristen Zhang¹, Ada Chen¹, Rhiannon Thomas-Tran¹, Joel Beatty¹, Debashis Mandal¹, Guifen Xu¹, Steve Young¹, Matthew Walters¹, Ulrike Schindler¹, Jay Powers¹

1Arcus Biosciences, Hayward, CA, USA

Tumor microenvironment | Immune suppression

P495

Separate molecular pathways mediate anti-tumor versus tumor-promoting Aspects of dsRNA signaling in cancer microenvironments

Marie-Nicole Theodoraki¹, Saumendra Sarkar¹, Ravi Muthuswamy¹, Jamie Voyten¹, Robert Edwards², David Bartlett¹, Kalinski Pawel¹

1University of Pittsburgh, Pittsburgh, PA, USA ²Magee-Womens Hospital of UPMC, Pittsburgh, PA, USA

Immune suppression | Tumor microenvironment | TLR

P496

Degradation of hyaluronan (HA) by PEGPH20 promotes anti-tumor immunity and enhances the effect of checkpoint blockade in an HA-accumulating mouse syngeneic tumor model

Benjamin J Thompson¹, Renee Clift¹, Trevor B Kimbler¹, Jesse D Bahn¹, Chunmei Zhao¹, Barbara Blouw¹, Curtis B Thompson¹, Sanna Rosengren¹

1Halozyme, San Diego, CA, USA

Tumor microenvironment | Tumor stroma | Immune suppression | Tumor infiltrating lymphocytes (TILs) | Checkpoint blockade | Immune contexture

P497

Tumor microenvironment immune gene signature asscoiated with axicabtagene ciloleucel (axi-cel, KTE-C19), an anti-CD19 chimeric antigen receptor (CAR) T cell, in a multicenter trial (ZUMA-1)

John Rossi¹, Jérôme Galon², Sarah Turcan², Corinne Danan², Frederick Locke³, Sattva Neelapu⁴, David Miklos⁵, Nancy Bartlett⁶, Caron Jacobson⁷, Ira Braunschweig⁸, Olalekan Oluwole⁹, Tanya Siddiqi¹⁰, Yi Lin¹¹, John Timmerman¹², Patrick Reagan¹³, Lazaros Lekakis¹⁴, Sherryonne Unabia¹, William Go¹, Jeff Wiezorek¹, Adrian Bot¹

1Kite Pharma, Santa Monica, CA, USA ²HalioDx, Marseille, France ³Moffitt Cancer Center, Tampa, FL, USA ⁴MD Anderson Cancer Center, Houston, TX, USA ⁵Stanford University School of Medicine, Stanford, CA, USA ⁶Washington University Medical School, Saint Louis, MO, USA ⁷Dana-Farber Cacner Institute, Boston, MA, USA ⁸Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY, USA ⁹Vanderbilt-Ingram Cancer Center, Nashville, TN, USA ¹⁰City of Hope National Medical Center, Duarte, CA, USA ¹¹Mayo Clinic, Rochester, MN, USA ¹²UCLA David Geffen School of Medicine, Santa Monica, CA, USA ¹³University of Rochester Medical Center, Rochester, NY, USA ¹⁴University of Miami Health System, Sylvester Comprehensive Care Center, Miami, FL, USA

CAR T cells | Biomarkers | T cell | Tumor microenvironment | Adoptive immunotherapy | Inflammation | Immune contexture

P498

AB928, a dual antagonist of the A_2aR and A_2bR adenosine receptors for the treatment of cancer

Matthew Walters¹, Daniel DiRenzo¹, Joanne Tan¹, Ulrike Schindler¹, Dana Piovesan¹, Devika Ashok¹, Tim Park¹, Nell Narasappa¹, Fangfang Yin¹, Wan Hsin Lim¹, Stefan Garrido-Shaqfeh¹, Jenna Jeffrey¹, Laurent Debien¹, Brandon Rosen¹, Ehesan Sharif¹, Dillon Miles¹, Manmohan Leleti¹, Juan Jaen¹, Jay Powers¹

1Arcus Biosciences, Hayward, CA, USA

Tumor microenvironment | T cell | Myeloid cells | Monocyte/Macrophage

P499

Expression pattern and prognostic value of IL-36g in colorectal cancer

Aliyah M Weinstein¹, Nicolas A Giraldo², Catherine Julie³, Laetitia Lacroix², Florent Petitprez², Jean-François Emile³, Wolf H Fridman², Walter J Storkus¹, Catherine Sautès-Fridman²

1University of Pittsburgh, Pittsburgh, PA, USA ²UMR_S1138, Centre de Recherche des Cordeliers, Paris, France ³Hopital Ambroise Paré, Boulogne, France

Tumor microenvironment | Tumor stroma | Tumor infiltrating lymphocytes (TILs) | Monocyte/Macrophage | Dendritic cell | Cytokine | Clinical study | Biomarkers | T cell | Myeloid cells

P500

CD73 blockade restores the abscopal response to radiation therapy and anti-CTLA-4 in cGAS-deficient tumors

Erik Wennerberg¹, Claire Vanpouille-Box¹, Silvia Chiara Formenti¹, Sandra Demaria¹

1Weill Cornell Medicine, New York, NY, USA

Antigen presenting cells | Dendritic cell | Tumor microenvironment | Checkpoint blockade | Immune suppression | Radiotherapy | Tumor infiltrating lymphocytes (TILs) | Vaccine

P501

Involvement of local renin-angiotensin system in immunosuppression of tumor microenvironment and its modulation for augmentation of cancer immunotherapy

Tomonori Yaguchi¹, Kenta Nakamura², Kenji Morii¹, Yutaka Kawakami¹

1Keio University School of Medicine, Shinjuku-ku, Tokyo, Japan ²Shinshu University School of medicine, Matsumoto, Nagano, Japan

Tumor evasion | Tumor stroma | Immune tolerance | Tumor microenvironment | Checkpoint blockade | MDSC

P502

IDO1, an immune checkpoint with distinct mechanisms and prognostic significance in glioblastoma

Lijie Zhai¹, Derek Wainwright¹, Erik Ladomersky¹, Carlos Dostal², Kristen Lauing¹, Robert McCusker², David Binder³, Meijing Wu¹, Matthew Genet¹, Galina Gritsina¹, Balaz Gyorffy⁴, Priscilla Brastinanos⁵, Jeffrey Sosman¹, Craig Horbinski¹, David James¹, Roger Stupp¹, Francis Giles¹

1Northwestern University Feinberg School of Medicine, Chicago, IL, USA ²University of Illinois at Urbana-Champaign, Urbana, IL, USA ³University of Colorado School of Medicine, Aurora, CO, USA ⁴Semmelweis University, Budapest, Hungary ⁵Massachusetts General Hospital, Boston, MA, USA

Immune tolerance | Tumor infiltrating lymphocytes (TILs) | Tumor microenvironment

P503

Comprehensive characterization of immune microenvironment of cholangiocarcinoma

Tao Xia¹, Dwayne Thomas¹, Linda Chen¹, Qingfeng Zhu¹, Jin He¹, Robert Anders¹, Shafat Quadri², Elaine Pinherio², Adrian Murphy¹, Lei Zheng¹

1Johns Hopkins University School of Medicine, Baltimore, MD, USA ²Merck, Merck, NJ, USA

Biomarkers | Myeloid cells | Tumor microenvironment | Immune suppression | Solid tumors | T cell | Tumor infiltrating lymphocytes (TILs) | Checkpoint blockade