title: Prolonged survival of patients with lung adenocarcinoma expressing XAGE-1b and HLA class I antigens.
abstract: XAGE-1b is a cancer/testis antigen that has been shown to be expressed at a significant frequency and to be immunogenic in non-small cell lung cancer (NSCLC). In the present study, we investigated correlations between XAGE-1b expression and NSCLC patient survival. XAGE-1b expression was examined immunohistochemically using USO9-13, an anti-XAGE-1b monoclonal antibody, in 121 NSCLCs (83 adenocarcinomas and 38 other histological types). XAGE-1b expression was observed in 27 (32.5%) adenocarcinoma specimens. In the other histological types, positive staining was observed in only 1 specimen. HLA class I expression in these samples was assessed previously. XAGE-1b expression had no correlation with overall survival. However, both XAGE-1b and HLA class I expression correlated with prolonged survival (P = 0.019). Moreover, expression of XAGE-1b combined with down-regulated HLA class I expression correlated with poor survival (P = 0.01). The density of cancer nest-infiltrating CD8+ T-cells in tumors expressing both XAGE-1b and HLA class I was higher than that in other groups. The findings suggest that XAGE-1b and HLA class I expression elicited a CD8+ T-cell response against minimal residual disease after surgery and resulted in prolonged survival of NSCLC patients.
authors.affiliation: First Department of Medicine, Hokkaido University School of Medicine, North 15 West 7, Kita-ku, Sapporo 060-8638, Japan. eikik@med.hokudai.ac.jp
authors.forename: Eiki
authors.initials: E
authors.lastname: Kikuchi
authors.forename: Koichi
authors.initials: K
authors.lastname: Yamazaki
authors.forename: Eiichi
authors.initials: E
authors.lastname: Nakayama
authors.forename: Shuichiro
authors.initials: S
authors.lastname: Sato
authors.forename: Akiko
authors.initials: A
authors.lastname: Uenaka
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Yamada
authors.forename: Satoshi
authors.initials: S
authors.lastname: Oizumi
authors.forename: Hirotoshi
authors.initials: H
authors.lastname: Dosaka-Akita
authors.forename: Masaharu
authors.initials: M
authors.lastname: Nishimura