title: Low Frequency of Programmed Death Ligand 1 Expression in Pediatric Cancers.
abstract: Programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) pathway blockade has become a promising therapeutic target in adult cancers. We evaluated PD-L1 expression and tumor-infiltrating CD8(+) T cells in formalin-fixed, paraffin-embedded tumor specimens from 53 untreated pediatric patients with eight cancer types: neuroblastoma, extracranial malignant germ cell tumor, hepatoblastoma, germinoma, medulloblastoma, renal tumor, rhabdomyosarcoma, and atypical teratoid/rhabdoid tumor. One rhabdomyosarcoma with the shortest survival exhibited membranous PD-L1 expression and germinoma contained abundant tumor-infiltrating CD8(+) T cells and PD-L1-positive macrophages. The PD-1/PD-L1 pathway tended to be inactive in pediatric cancers.
authors.affiliation: Department of Pediatrics, Graduate School of Medicine, Chiba University, Chiba, Japan.|Department of Medical Immunology, Graduate School of Medicine, Chiba University, Chiba, Japan.|Department of Hematology/Oncology, Saitama Children's Medical Center, Saitama, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Aoki
authors.affiliation: Department of Pediatrics, Graduate School of Medicine, Chiba University, Chiba, Japan.
authors.forename: Moeko
authors.initials: M
authors.lastname: Hino
authors.affiliation: Department of Hematology/Oncology, Saitama Children's Medical Center, Saitama, Japan.
authors.forename: Katsuyoshi
authors.initials: K
authors.lastname: Koh
authors.affiliation: Department of Clinical Laboratory, Saitama Children's Medical Center, Saitama, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Kyushiki
authors.affiliation: Department of Clinical Laboratory, Saitama Children's Medical Center, Saitama, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kishimoto
authors.affiliation: Department of Hematology/Oncology, Saitama Children's Medical Center, Saitama, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Arakawa
authors.affiliation: Department of Hematology/Oncology, Saitama Children's Medical Center, Saitama, Japan.
authors.forename: Ryoji
authors.initials: R
authors.lastname: Hanada
authors.affiliation: Department of Pediatric Surgery, Saitama Children's Medical Center, Saitama, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kawashima
authors.affiliation: Department of Neurosurgery, Saitama Children's Medical Center, Saitama, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Kurihara
authors.affiliation: Department of Pediatrics, Graduate School of Medicine, Chiba University, Chiba, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Shimojo
authors.affiliation: Department of Medical Immunology, Graduate School of Medicine, Chiba University, Chiba, Japan.
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Motohashi
mesh_terms: D000293:Adolescent; D060890:B7-H1 Antigen / Q000378:metabolism*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D016246:Lymphocytes, Tumor-Infiltrating / Q000276:immunology; D008264:Macrophages / Q000276:immunology*; D009369:Neoplasms / Q000473:pathology*; D061026:Programmed Cell Death 1 Receptor / Q000378:metabolism*; D012189:Retrospective Studies; D059016:Tumor Microenvironment / Q000276:immunology
chemical_list: D060890:B7-H1 Antigen; C423236:CD274 protein, human; C105992:PDCD1 protein, human; D061026:Programmed Cell Death 1 Receptor
keywords: PD-1/PD-L1 blockade; pediatric cancer; tumor-infiltrating lymphocyte