PUB044 TIM-3 Protein Expression in Non-Small Cell Lung Cancer and Its Relationship with PD-1/PD-L1 and Tumor-Infiltrating Lymphocytes

Abstract

Immunotherapy targeting the programmed death-1 (PD-1) / programmed death ligand-1 (PD-L1) checkpoint has shown promising efficacy in patients with non-small cell lung cancer (NSCLC). T-cell immunoglobulin domain and mucin domain-3 (TIM-3) is another important checkpoint, and its role in NSCLC is still not clear. In this study, we investigated TIM-3 protein expression and its correlation with PD-1, PD-L1, tumor-infiltrating lymphocytes (TILs), and association with survival in NSCLC. TIM-3 (D5D5R, Cell signaling), PD-1 (NAT 105, Cell marque) and PD-L1 (22C3, Dako) protein expression was evaluated by IHC, and TIL abundance was scored, in 132 surgically resected specimens from patients with NSCLC. TIM-3 was expressed on the TILs in 18 (13.6%) patients. 58 patient samples (43.9%) were positive for PD-1 on the TILs, and 23 (17.4%) were positive for PD-L1 on tumor cells. Neither TIM -3 nor PD-1 was expressed on the tumor cells. TIM-3 was over expressed on the TILs in adenocarcinoma compared to non-adenocarcinoma (P=0.011). TIM-3 expression on TILs was significantly correlated to that of PD-1 on TILs (P=0.011). In our study, there was no significant difference in recurrence-free survival (RFS) and overall survival (OS) between TIM-3 positive and negative. TIM-3 expresses on TILs in tumor tissues of some NSCLC patients. Its expression was higher in adenocarcinoma and was correlated with PD-1.