title: PD-1/PD-L1 blockade in cancer treatment: perspectives and issues.
abstract: Recent studies showed that tumor cells 'edit' host immunity in several ways to evade immune defenses in the tumor microenvironment. This phenomenon is called "cancer immune escape." One of the most important components in this system is an immunosuppressive co-signal (immune checkpoint) mediated by the PD-1 receptor and its ligand, PD-L1. PD-1 is mainly expressed on activated T cells, whereas PD-L1 is expressed on several types of tumor cells. Preclinical studies have shown that inhibition of the interaction between PD-1 and PD-L1 enhances the T-cell response and mediates antitumor activity. Several clinical trials of PD-1/PD-L1 signal-blockade agents have exhibited dramatic antitumor efficacy in patients with certain types of solid or hematological malignancies. In this review, we highlight recent clinical trials using anti-PD-1 or anti-PD-L1 antibodies against several types of malignancies, including a trial conducted in our department, and describe the clinical perspectives and issues regarding the PD-1/PD-L1 blockade in cancer treatment.
authors.affiliation: Department of Gynecology and Obstetrics, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, Kyoto, 606-8507, Japan. jnkhmns@kuhp.kyoto-u.ac.jp.
authors.forename: Junzo
authors.initials: J
authors.lastname: Hamanishi
authors.affiliation: Department of Obstetrics and Gynecology, Kinki University Faculty of Medicine, Osaka, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Mandai
authors.affiliation: Department of Gynecology and Obstetrics, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, Kyoto, 606-8507, Japan.
authors.forename: Noriomi
authors.initials: N
authors.lastname: Matsumura
authors.affiliation: Department of Gynecology and Obstetrics, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, Kyoto, 606-8507, Japan.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Abiko
authors.affiliation: Department of Gynecology and Obstetrics, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, Kyoto, 606-8507, Japan.
authors.forename: Tsukasa
authors.initials: T
authors.lastname: Baba
authors.affiliation: Department of Gynecology and Obstetrics, Kyoto University Graduate School of Medicine, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, Kyoto, 606-8507, Japan.
authors.forename: Ikuo
authors.initials: I
authors.lastname: Konishi
mesh_terms: D000911:Antibodies, Monoclonal / Q000009:adverse effects / Q000627:therapeutic use*; D060890:B7-H1 Antigen / Q000037:antagonists & inhibitors*; D014408:Biomarkers, Tumor; D002986:Clinical Trials as Topic; D006801:Humans; D007167:Immunotherapy; D009369:Neoplasms / Q000628:therapy*; D061026:Programmed Cell Death 1 Receptor / Q000037:antagonists & inhibitors*; D013601:T-Lymphocytes / Q000276:immunology; D019139:Tumor Escape / Q000276:immunology; D059016:Tumor Microenvironment / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D060890:B7-H1 Antigen; D014408:Biomarkers, Tumor; D061026:Programmed Cell Death 1 Receptor
keywords: Biomarker; Immunotherapy; Nivolumab; PD-1; PD-L1; Value