title: Clinical impact of tumor-infiltrating CD45RO⁺ memory T cells on human gastric cancer.
abstract: Memory T cells survive for months and even years and are critical for host defense in humans. They have been recently suggested to play a significant role in tumor immunity. In this study, we aimed to investigate the clinical impact of tumor-infiltrating memory T cells on human gastric cancer. We evaluated CD45RO(+)T cells infiltrating into primary gastric cancer tissues by immunohistochemistry in 101 patients with gastric cancer. Patients were classified into 2 groups (CD45RO(+Hi) and CD45RO(+Lo)) based on the number of positively stained T cells. There was no significant correlation observed between CD45RO status and post-operative prognosis in early gastric cancer. By contrast, in advanced cancer, the post-operative overall and disease-free survival of patients with CD45RO(+Hi) were significantly improved compared to those of patients with CD45RO(+Lo). In addition, CD45RO status in the primary tumors significantly correlated with the development of post-operative recurrence, particularly peritoneal recurrence. Furthermore, the local expression of interferon-γ (IFN-γ) in the CD45RO(+Hi) tumors was significantly higher than that in the CD45RO(+Lo) tumors, suggesting that CD45RO(+) T cells induced local immune activation. Multivariate analysis indicated that the CD45RO(+) status was an independent prognostic factor in advanced gastric cancer. In conclusion, tumor-infiltrating CD45RO(+) memory T cells are functional and have significant prognostic value in human gastric cancer. Our data suggest that adaptive immune response is clinically critical in gastric cancer.
authors: Department of Surgery, Nara Medical University, Nara 634-8522, Japan.
authors: Kohei
authors: K
authors: Wakatsuki
authors: Masayuki
authors: M
authors: Sho
authors: Ichiro
authors: I
authors: Yamato
authors: Tomoyoshi
authors: T
authors: Takayama
authors: Sohei
authors: S
authors: Matsumoto
authors: Tetsuya
authors: T
authors: Tanaka
authors: Kazuhiro
authors: K
authors: Migita
authors: Masahiro
authors: M
authors: Ito
authors: Kiyohiko
authors: K
authors: Hotta
authors: Yoshiyuki
authors: Y
authors: Nakajima
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007156:Immunologic Memory / Q000276:immunology*; D007371:Interferon-gamma / Q000276:immunology; D017493:Leukocyte Common Antigens / Q000276:immunology*; D016246:Lymphocytes, Tumor-Infiltrating / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000276:immunology; D011379:Prognosis; D013274:Stomach Neoplasms / Q000276:immunology*
chemical_list: D007371:Interferon-gamma; D017493:Leukocyte Common Antigens