title: Prognostic impact of programmed cell death 1 ligand 1 expression in human leukocyte antigen class I-positive hepatocellular carcinoma after curative hepatectomy.
abstract: BACKGROUND
  Hepatocellular carcinoma (HCC) is one of the most common solid tumors worldwide. Surgery is potentially curative, but high recurrence rates worsen patient prognosis. The interaction between the proteins programmed cell death 1 (PD-1) and programmed cell death 1 ligand 1 (PD-L1) is an important immune checkpoint. The significance of PD-L1 expression and human leukocyte antigen class I (HLA class I), recognized by CD8 T cells, in the prognosis of patients with HCC remains to be determined.
  
  
  METHODS
  We assessed the levels of PD-L1 and HLA class I expression on HCC samples from 80 patients who had undergone hepatectomy at our institution, and evaluated the correlations between PD-L1 and HLA class I expression and patient prognosis.
  
  
  RESULTS
  High HLA class I expression was correlated with significantly better recurrence-free survival (RFS), but not overall survival (OS). Multivariate analysis showed that high HLA class I expression was an independent predictor of improved RFS. Low expression of PD-L1 on HCC tended to predict better OS, but the difference was not statistically significant. PD-L1 expression on HCC correlated with the number of CD163-positive macrophages and HLA class I expression with CD3-positive cell infiltration. Univariable and multivariable analyses showed that combined PD-L1 low/HLA class I high expression on HCCs was prognostic for improved OS and RFS.
  
  
  CONCLUSIONS
  PD-L1 status may be a good predictor of prognosis in HCC patients with high HLA class I expression. Novel therapies targeting the PD-L1/PD-1 pathway may improve the prognosis of patients with HCC.
authors: Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, 812-8582, Japan.
authors: Yuichiroh
authors: Y
authors: Umemoto
authors: Shinji
authors: S
authors: Okano
authors: Yoshihiro
authors: Y
authors: Matsumoto
authors: Hidekazu
authors: H
authors: Nakagawara
authors: Rumi
authors: R
authors: Matono
authors: Shohei
authors: S
authors: Yoshiya
authors: Yo-Ichi
authors: Y
authors: Yamashita
authors: Tomoharu
authors: T
authors: Yoshizumi
authors: Toru
authors: T
authors: Ikegami
authors: Yuji
authors: Y
authors: Soejima
authors: Mamoru
authors: M
authors: Harada
authors: Shinichi
authors: S
authors: Aishima
authors: Yoshinao
authors: Y
authors: Oda
authors: Ken
authors: K
authors: Shirabe
authors: Yoshihiko
authors: Y
authors: Maehara
mesh_terms: D000368:Aged; D060890:B7-H1 Antigen / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000378:metabolism*; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology / Q000601:surgery; D005260:Female; D006498:Hepatectomy; D015395:Histocompatibility Antigens Class I / Q000378:metabolism*; D006801:Humans; D007371:Interferon-gamma / Q000276:immunology; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology / Q000601:surgery; D016246:Lymphocytes, Tumor-Infiltrating / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000378:metabolism; D011379:Prognosis; D016019:Survival Analysis
chemical_list: D060890:B7-H1 Antigen; D014408:Biomarkers, Tumor; C423236:CD274 protein, human; D015395:Histocompatibility Antigens Class I; D009363:Neoplasm Proteins; D007371:Interferon-gamma