Prognostic value of programmed death-1, programmed death-ligand 1, programmed death-ligand 2 expression, and CD8(+) T cell density in primary tumors and metastatic lymph nodes from patients with stage T1-4N+M0 gastric adenocarcinoma
- Author:
Gao YUAN
1
,
2
,
3
;
Li SU
;
Xu DAZHI
;
Chen SHANGXIANG
;
Cai YUCHEN
;
Jiang WENQI
;
Zhang XINKE
;
Sun JIN
;
Wang KEFENG
;
Chang BOYANG
;
Wang FENGHUA
;
Hong MINGHUANG
Author Information
1. Sun Yat-sen University Cancer Center
2. State Key Laboratory of Oncology in South China
3. Collaborative Innovation Center for Cancer Medicine
- Keywords:
Gastric cancer;
Programmed cell death-ligand 1;
Programmed cell death-ligand 2;
Programmed cell death-1;
CD8(+) T cells;
Heterogeneity expression;
Prognostic value
- From:Chinese Journal of Cancer
2017;36(11):560-573
- CountryChina
- Language:Chinese
-
Abstract:
Background: Anti-programmed death-1/programmed death-ligand 1 (PD-1/PD-L1) immunotherapy has been proved to be effective on gastric cancer in ongoing clinical trials. However, the value of PD-L1 in predicting responses of patients with gastric cancer to anti-PD-1/PD-L1 immunotherapy is controversial. Some studies suggested that intra- and inter-tumoral heterogeneity of PD-L1 expression might explain the controversy. This study aimed to analyze the expression of PD-L1, PD-L2, and PD-1 as well as CD8(+) T-cell density in primary tumors and lymph nodes from patients with stage T1-4N+M0 gastric adenocarcinoma to explore the heterogeneity of PD-1 signaling pathway molecules. Methods: In primary tumors and metastatic as well as non-metastatic lymph nodes from patients with stage T1-4N+M0 gastric adenocarcinoma, we detected PD-L1 and PD-L2 expression with immunohistochemistry. CD8(+) T-cell density in primary tumors and PD-1 expression on CD8(+) T cells were detected with immunofluorescence. Uni-variate analysis was used to determine the prognostic values of them. Cox proportional hazard regression model was used to identify independent risk factors that affect patients' overall survival and disease-free survival. Results: Among 119 eligible patients who had undergone surgical resection, the positive rate of PD-L1 was higher in metastatic lymph nodes than in primary tumors (45.4％ vs. 38.7％,P= 0.005); the positive rate of PD-1 on CD8(+) T cells was significantly higher in primary tumors and metastatic lymph nodes than in tumor-free lymph nodes (both P < 0.001). The intensity of PD-1 expression on CD8(+) T cells in primary tumors and in metastatic lymph nodes were stronger than that in tumor-free lymph nodes from the same patient. Beside, the positive rate of PD-L2 did not show any differences between primary tumors and metastatic lymph nodes. In multivariate analysis, PD-L1 expression, PD-L2 expression, a low density of CD8(+) T cells in primary tumors, and PD-1 expression on CD8(+) T cells in primary tumors were associated with poor prognosis.Conclusion: The expression of PD-L1 is heterogeneous in primary tumors and in metastatic lymph nodes from patients with stage T1-4N+M0 gastric adenocarcinoma, which might explain the inconsistent results in assessing the prognostic value of PD-L1 expression in previous studies.
