Immune Netw. 2020 Feb;20(1):e3 https://doi.org/10.4110/in.2020.20.e3 pISSN 1598-2629·eISSN 2092-6685
Review Article Co-Stimulatory Receptors in Cancers and Their Implications for Cancer Immunotherapy
Seongju Jeong 1, Su-Hyung Park 1,2,*
1Biomedical Science and Engineering Interdisciplinary Program, KAIST, Daejeon 34141, Korea 2Laboratory of Translational Immunology and Vaccinology, Graduate School of Medical Science and Engineering, KAIST, Daejeon 34141, Korea
Received: Jan 5, 2020 ABSTRACT Revised: Jan 27, 2020 Accepted: Jan 27, 2020 Immune checkpoint inhibitors (ICIs), including anti-PD-1 and anti-CTLA-4 therapeutic *Correspondence to agents, are now approved by the Food and Drug Administration for treatment of various types Su-Hyung Park of cancer. However, the therapeutic efficacy of ICIs varies among patients and cancer types. Laboratory of Translational Immunology and Vaccinology, Graduate School of Medical Moreover, most patients do not develop durable antitumor responses after ICI therapy due Science and Engineering, KAIST, 291 Daehak-ro, to an ephemeral reversal of T-cell dysfunction. As co-stimulatory receptors play key roles in Yuseong-gu, Daejeon 34141, Korea. regulating the effector functions of T cells, activating co-stimulatory pathways may improve E-mail: [email protected] checkpoint inhibition efficacy, and lead to durable antitumor responses. Here, we review
Copyright © 2020. The Korean Association of recent advances in our understating of co-stimulatory receptors in cancers, providing the Immunologists necessary groundwork for the rational design of cancer immunotherapy. This is an Open Access article distributed under the terms of the Creative Commons Keywords: Cancer, Immunotherapy; Costimulatory T-cell receptors; T-Lymphocytes Attribution Non-Commercial License (https:// creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any INTRODUCTION medium, provided the original work is properly cited. Immunotherapy has long been considered an important cancer treatment option, and immune checkpoint inhibitors (ICIs) targeting PD-1, PD-L1, and CTLA-4 have revolutionized ORCID iDs Seongju Jeong cancer treatment (1). Many studies have examined the features of tumor-infiltrated https://orcid.org/0000-0001-5866-7260 lymphocytes (TILs) in the tumor microenvironment and the mechanisms by which cancers Su-Hyung Park evade immune response, elucidating the concept of CD8 T-cell exhaustion, which is critical https://orcid.org/0000-0001-6363-7736 for improving cancer immunotherapy. T-cell exhaustion was first described in chronic
Conflicts of Interest viral infection, and is defined as an impaired capacity of T cells to secrete cytokines and The authors declare no potential conflicts of proliferate, caused by prolonged antigenic stimulation-induced overexpression of immune interest. checkpoint receptors, such as PD-1, CTLA-4, T-cell Ig and mucin-domain containing (TIM)-3, and lymphocyte-activation gene 3 (2). Since response to ICI treatment substantially varies Abbreviations among patients and cancer types, it is important to develop novel immuno-therapeutic 4-1BBL, 4-1BB ligand; ADCC, Ab-dependent cellular cytotoxicity; APC, Ag-presenting cell; strategies with improved therapeutic efficacy. CAR, chimeric Ag receptor; DC, dendritic cell; DR-3, death receptor 3; GITR, glucocorticoid- Various therapeutic strategies that have been considered to improve the anti-tumor response induced TNF receptor-related protein; to checkpoint blockades, include combinations of multiple checkpoint blockers, agonistic GITRL, GITR ligand; HCC, hepatocellular mAb targeting co-stimulatory receptors, soluble mediators (cytokines), and chimeric Ag carcinoma; ICI, immune checkpoint inhibitor; ICOS, inducible T-cell co-stimulator; ICOSL, receptor (CAR) T cells (2). In addition to inhibitory receptors, activated T cells and exhausted ICOS ligand; IgSF, Ig receptor superfamily; T cells in tumor microenvironment also exhibit upregulation of numerous co-stimulatory https://immunenetwork.org 1/20 Co-Stimulatory Receptors as Targets for Cancer Immunotherapy
LCMV, lymphocytic choriomeningitis virus; receptors (3) (Fig. 1). Since immune-stimulating co-stimulatory receptors are an essential NSCLC, non-small-cell lung cancer; OC, element of anti-cancer immunity, effective activation of these receptors may contribute ovarian cancer; OX40L, OX40 ligand; pGITRL, to the therapeutic repertoires against cancers. Moreover, it has been suggested that T-cell pentamerized form of the GITRL extracellular domain; SLAM, signaling lymphocytic exhaustion and T-cell activation are closely interconnected and share features related to the activation molecule; SLAMF6, signaling cell cycle pathway, T-cell migration, and cytotoxic effector function (4,5). Therefore, one lymphocytic activation molecule family promising therapeutic approach is to target co-stimulatory receptors using agonistic mAb for member 6; TCF-1, T-cell factor 1; Tfh, follicular re-invigorating T-cell responses in cancers. helper T; TIGIT, T cell Ig and ITIM domain; TIM, T-cell Ig and mucin-domain containing; Here, we review recent advances in our understating of various co-stimulatory receptors TIL, tumor-infiltrated lymphocyte; TNFR, TNF receptor; TNFRSF, TNF receptor superfamily; belonging to the Ig receptor superfamily (IgSF) and the TNF receptor superfamily (TNFRSF) TRAF, TNF receptor-associated factor in cancers. We focus on the immunological characteristics of these co-stimulatory receptors and also highlight the current status of anti-cancer immunotherapeutic strategies targeting Author Contributions each co-stimulatory receptor. Conceptualization: Jeong S, Park SH; Writing - original draft: Jeong S, Park SH; Writing - review & editing: Jeong S, Park SH. a ng gna n ry gna