Journal Articles

Host tissue determinants of tumour immunity

Although common evolutionary principles drive the growth of cancer cells regardless of the tissue of origin, the microenvironment in which tumours arise substantially differs across various organ sites. Recent studies have established that, in addition to cell-intrinsic effects, tumour growth regulation also depends on local cues driven by tissue environmental factors. In this Review, we discuss how tissue-specific determinants might influence tumour development and argue that unravelling the tissue-specific contribution to tumour immunity should help the development of precise immunotherapeutic strategies for patients with cancer.

Author Info: (1) Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA. helene.salmon@curie.fr. Precision Immunology Institute and Tisch Cancer Institut

Author Info: (1) Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA. helene.salmon@curie.fr. Precision Immunology Institute and Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA. helene.salmon@curie.fr. INSERM U932, Institut Curie, Paris, France. helene.salmon@curie.fr. (2) Innate Pharma, Marseille, France. (3) Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA. Precision Immunology Institute and Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA. Department of Hematology and Oncology, Icahn School of Medicine at Mount Sinai, New York, NY, USA. (4) Department of Oncological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA. miriam.merad@mssm.edu. Precision Immunology Institute and Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA. miriam.merad@mssm.edu.

An antibody-drug conjugate directed to the ALK receptor demonstrates efficacy in preclinical models of neuroblastoma

Enthusiasm for the use of antibody-drug conjugates (ADCs) in cancer therapy has risen over the past few years. The success of this therapeutic approach relies on the identification of cell surface antigens that are widely and selectively expressed on tumor cells. Studies have shown that native ALK protein is expressed on the surface of most neuroblastoma cells, providing an opportunity for development of immune-targeting strategies. Clinically relevant antibodies for this target have not yet been developed. Here, we describe the development of an ALK-ADC, CDX-0125-TEI, which selectively targets both wild-type and mutated ALK-expressing neuroblastomas. CDX-0125-TEI exhibited efficient antigen binding and internalization, and cytotoxicity at picomolar concentrations in cells with different expression of ALK on the cell surface. In vivo studies showed that CDX-0125-TEI is effective against ALK wild-type and mutant patient-derived xenograft models. These data demonstrate that ALK is a bona fide immunotherapeutic target and provide a rationale for clinical development of an ALK-ADC approach for neuroblastomas and other ALK-expressing childhood cancers such as rhabdomyosarcomas.

Author Info: (1) Division of Oncology and Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA. (2) Division of Oncology and Center for Childho

Author Info: (1) Division of Oncology and Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA. (2) Division of Oncology and Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA. (3) Division of Oncology and Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA. (4) Division of Oncology and Center for Biomedical Informatics (CBMi), Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA. (5) Department of Pathology, Children's Hospital of Philadelphia and Department of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA. (6) Celldex Therapeutics Inc., New Haven, CT 06511, USA. (7) Celldex Therapeutics Inc., New Haven, CT 06511, USA. (8) Nerviano Medical Sciences S.r.l., Nerviano (MI) 20014, Italy. (9) Nerviano Medical Sciences S.r.l., Nerviano (MI) 20014, Italy. (10) Nerviano Medical Sciences S.r.l., Nerviano (MI) 20014, Italy. (11) Department of Pathology, Children's Hospital of Philadelphia and Department of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA. (12) Celldex Therapeutics Inc., New Haven, CT 06511, USA. (13) Division of Oncology and Center for Childhood Cancer Research, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA. mosse@chop.edu. Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA 19104, USA.

Recent clinical trials of immunotherapy in non-small-cell lung cancer

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Author Info: (1) Medical Oncology Department, BOC Oncology Center, Nicosia 2006, Cyprus. (2) 2nd Medical Oncology Department, Henry Dunant Hospital Center, Athens 11526, Greece.

Author Info: (1) Medical Oncology Department, BOC Oncology Center, Nicosia 2006, Cyprus. (2) 2nd Medical Oncology Department, Henry Dunant Hospital Center, Athens 11526, Greece.

Deciphering CD4(+) T cell specificity using novel MHC-TCR chimeric receptors

alphabeta T cell antigen receptors (TCRs) bind complexes of peptide and major histocompatibility complex (pMHC) with low affinity, which poses a considerable challenge for the direct identification of alphabeta T cell cognate peptides. Here we describe a platform for the discovery of MHC class II epitopes based on the screening of engineered reporter cells expressing novel pMHC-TCR (MCR) hybrid molecules carrying cDNA-derived peptides. This technology identifies natural epitopes of CD4(+) T cells in an unbiased and efficient manner and allows detailed analysis of TCR cross-reactivity that provides recognition patterns beyond discrete peptides. We determine the cognate peptides of virus- and tumor-specific T cells in mouse disease models and present a proof of concept for human T cells. Furthermore, we use MCR to identify immunogenic tumor neo-antigens and show that vaccination with a peptide naturally recognized by tumor-infiltrating lymphocytes efficiently protects mice from tumor challenge. Thus, the MCR technology holds promise for basic research and clinical applications, allowing the personalized identification of T cell-specific neo-antigens in patients.

Author Info: (1) Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland. jan.kisielow@biol.ethz.ch. (2) Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland.

Author Info: (1) Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland. jan.kisielow@biol.ethz.ch. (2) Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland. (3) Institute of Molecular Health Sciences, ETH Zurich, Zurich, Switzerland. manfred.kopf@ethz.ch.

Enhancing the antitumor functions of invariant natural killer T cells using a soluble CD1d-CD19 fusion protein

Invariant natural killer T (iNKT) cells comprise a unique lineage of CD1d-restricted lipid-reactive T lymphocytes that potently kill tumor cells and exhibit robust immunostimulatory functions. Optimal tumor-directed iNKT cell responses often require expression of the antigen-presenting molecule CD1d on tumors; however, many tumor cells downregulate CD1d and thus evade iNKT cell recognition. We generated a soluble bispecific fusion protein designed to direct iNKT cells to the site of B-cell cancers in a tumor antigen-specific but CD1d-independent manner. This fusion protein is composed of a human CD1d molecule joined to a single chain antibody FV fragment specific for CD19, an antigen widely expressed on B-cell cancers. The CD1d-CD19 fusion protein binds specifically to CD19-expressing, but not CD19-negative cells. Once loaded with the iNKT cell lipid agonist alpha-galactosyl ceramide (alphaGC), the CD1d-CD19 fusion induces robust in vitro activation of and cytokine production by human iNKT cells. iNKT cells stimulated by the alphaGC-loaded CD1d-CD19 fusion also strongly transactivate T-, B-, and NK-cell responses and promote dendritic cell maturation. Importantly, the alphaGC-loaded fusion induces robust lysis of CD19(+)CD1d(-) Epstein-Barr virus immortalized human B-lymphoblastoid cell lines that are otherwise resistant to iNKT cell killing. Consistent with these findings; administration of the alphaGC-loaded fusion protein controlled the growth of CD19(+)CD1d(-) tumors in vivo, suggesting that it can "link" iNKT cells and CD19(+)CD1d(-) targets in a therapeutically beneficial manner. Taken together, these preclinical studies demonstrate that this B cell-directed fusion protein can be used to effectively induce iNKT cell antitumor responses in vitro and in vivo.

Author Info: (1) Department of Physiology, Michigan State University, East Lansing, MI. (2) Division of Oncology, Children's Hospital of Philadelphia, Philadelphia, PA. (3) Division of Oncology

Author Info: (1) Department of Physiology, Michigan State University, East Lansing, MI. (2) Division of Oncology, Children's Hospital of Philadelphia, Philadelphia, PA. (3) Division of Oncology, Children's Hospital of Philadelphia, Philadelphia, PA. (4) Division of Oncology, Children's Hospital of Philadelphia, Philadelphia, PA. (5) Department of Physiology, Michigan State University, East Lansing, MI. (6) Vaccinex Inc., Rochester, NY; and. (7) Vaccinex Inc., Rochester, NY; and. (8) Department of Oncology, St. Jude Children's Research Hospital, Memphis, TN.

Blocking expression of inhibitory receptor NKG2A overcomes tumor resistance to NK cells

A key mechanism of tumor resistance to immune cells is mediated by expression of peptide-loaded HLA-E in tumor cells, which suppresses natural killer (NK) cell activity via ligation of the NK inhibitory receptor CD94/NKG2A. Gene expression data from approximately 10,000 tumor samples showed widespread HLAE expression, with levels correlating with those of KLRC1 (NKG2A) and KLRD1 (CD94). To bypass HLA-E inhibition, we developed a way to generate highly functional NK cells lacking NKG2A. Constructs containing a single-chain variable fragment derived from an anti-NKG2A antibody were linked to endoplasmic reticulum-retention domains. After retroviral transduction in human peripheral blood NK cells, these NKG2A Protein Expression Blockers (PEBLs) abrogated NKG2A expression. The resulting NKG2Anull NK cells had higher cytotoxicity against HLA-E-expressing tumor cells. Transduction of anti-NKG2A PEBL produced more potent cytotoxicity than interference with an anti-NKG2A antibody and prevented de novo NKG2A expression, without affecting NK cell proliferation. In immunodeficient mice, NKG2Anull NK cells were significantly more powerful than NKG2A+ NK cells against HLA-E-expressing tumors. Thus, NKG2A downregulation evades the HLA-E cancer immune-checkpoint, and increases the anti-tumor activity of NK cell infusions. Because this strategy is easily adaptable to current protocols for clinical-grade immune cell processing, its clinical testing is feasible and warranted.

Author Info: (1) (2) (3) (4) (5)

Author Info: (1) (2) (3) (4) (5)

New epitopes in ovalbumin provide insights for cancer neoepitopes

MHC I-restricted epitopes of chicken ovalbumin (OVA) were originally identified using CD8 T cells as probes. Here, using bioinformatics tools, we identify four additional epitopes in OVA in addition to a cryptic epitope. Each new epitope is presented in vivo, as deduced from the lack of CD8 response to it in OVA-transgenic mice. In addition, CD8 responses to the known and novel epitopes are examined in C57BL/6 mice exposed to the OVA-expressing tumor E.G7 in several ways. No responses to any epitope including SIINFEKL are detected in mice with growing E.G7 or mice immunized with the tumor. Only in E.G7-bearing mice treated with an anti-CTLA4 antibody which depletes tumor-infiltrating regulatory T cells, CD8 responses to SIINFEKL and the novel epitope EKYNLTSVL are detected. Finally, all epitopes fails to treat mice with pre-existing tumors. These observations force an important re-consideration of the common assumptions about the therapeutic value of neoepitopes detected by CD8 responses in tumor-bearing hosts.

Author Info: (1) (2) (3) (4) (5) (6)

Author Info: (1) (2) (3) (4) (5) (6)

Genomic correlates of response to immune checkpoint blockade

Despite impressive durable responses, immune checkpoint inhibitors do not provide a long-term benefit to the majority of patients with cancer. Understanding genomic correlates of response and resistance to checkpoint blockade may enhance benefits for patients with cancer by elucidating biomarkers for patient stratification and resistance mechanisms for therapeutic targeting. Here we review emerging genomic markers of checkpoint blockade response, including those related to neoantigens, antigen presentation, DNA repair, and oncogenic pathways. Compelling evidence also points to a role for T cell functionality, checkpoint regulators, chromatin modifiers, and copy-number alterations in mediating selective response to immune checkpoint blockade. Ultimately, efforts to contextualize genomic correlates of response into the larger understanding of tumor immune biology will build a foundation for the development of novel biomarkers and therapies to overcome resistance to checkpoint blockade.

Author Info: (1) Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA. Broad Institute of MIT and Harvard, Cambridge, MA, USA. (2) Department of Medical Oncology, Dana-

Author Info: (1) Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA. Broad Institute of MIT and Harvard, Cambridge, MA, USA. (2) Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA. Department of Immunology, Harvard Medical School, Boston, MA, USA. (3) Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA. Eliezerm_vanallen@dfci.harvard.edu. Broad Institute of MIT and Harvard, Cambridge, MA, USA. Eliezerm_vanallen@dfci.harvard.edu.

Cancer immunotherapy with T cells carrying bispecific receptors that mimic antibodies

Tumors are inherently heterogeneous in antigen expression and escape from immune surveillance due to antigen loss remains one of the limitations of targeted immunotherapy. Despite the clinical use of adoptive therapy with chimeric antigen receptor (CAR)-redirected T cells in lymphoblastic leukemia, treatment failure due to epitope loss occurs. Targeting multiple tumor-associated antigens (TAA) may thus improve the outcome of CAR-T cell therapies. CARs developed to simultaneously target multiple targets are limited by the large size of each single-chain variable fragment and compromised protein folding when several single chains are linearly assembled. Here we describe single-domain antibody mimics that function within CAR parameters but form a very compact structure. We show that antibody mimics targeting EGFR and HER2 of the ErbB receptor tyrosine kinase family can be assembled into receptor molecules, which we call antibody mimic receptors (amR). These amR can redirect T cells to recognize two different epitopes of the same antigen or two different TAAs in vitro and in vivo.

Author Info: (1) Department of Microbiology & Immunology, University of North Carolina at Chapel Hill. (2) Eshelman School of Pharmacy, Division of Chemical Biology and Medicinal Chemistry, Uni

Author Info: (1) Department of Microbiology & Immunology, University of North Carolina at Chapel Hill. (2) Eshelman School of Pharmacy, Division of Chemical Biology and Medicinal Chemistry, University of North Carolina at Chapel Hill. (3) Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill. (4) Eshelman School of Pharmacy, Division of Chemical Biology and Medicinal Chemistry, University of North Carolina at Chapel Hill. (5) Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill. (6) Department of Oncology, Beijing Chest Hospital. (7) Pediatrics- Hematology/Oncology, University of North Carolina at Chapel Hill. (8) University of North Carolina at Chapel Hill. (9) Department of Microbiology and Immuniology, University of North Carolina at Chapel Hill gdotti@med.unc.edu.

Immunotherapy and targeted therapy combinations in metastatic breast cancer

Immunotherapy is emerging as a new treatment modality in breast cancer. After long-standing use of endocrine therapy and targeted biological therapy, improved understanding of immune evasion by cancer cells and the discovery of selective immune checkpoint inhibitors have created novel opportunities for treatment. Single-drug therapies with monoclonal antibodies against programmed death-1 (PD-1) and programmed death ligand-1 (PD-L1) have shown little efficacy in patients with metastatic breast cancer, in part because of the low number of tumour-infiltrating lymphocytes in most breast cancers. There is growing interest in the development of combinations of immunotherapy and molecularly targeted therapies for metastatic breast cancer. In this Personal View, we review the available data and ongoing efforts to establish the safety and efficacy of immunotherapeutic approaches in combination with HER2-targeted therapy, inhibitors of cyclin-dependent kinases 4 and 6, angiogenesis inhibitors, poly(ADP-ribose) polymerase inhibitors, as well as chemotherapy and radiotherapy.

Author Info: (1) Perlmutter Cancer Center, New York University Langone Health, New York, NY, USA. Electronic address: francisco.esteva@nyulangone.org. (2) Anna-Maria Kellen Clinical Accelerator

Author Info: (1) Perlmutter Cancer Center, New York University Langone Health, New York, NY, USA. Electronic address: francisco.esteva@nyulangone.org. (2) Anna-Maria Kellen Clinical Accelerator, Cancer Research Institute, New York, NY, USA. (3) Anna-Maria Kellen Clinical Accelerator, Cancer Research Institute, New York, NY, USA. (4) Yale School of Medicine, Yale Cancer Center, New Haven, CT, USA.