Combined inhibition of PD-1/PD-L1, Lag-3, and Tim-3 axes augments antitumor immunity in gastric cancer–T cell coculture models

Abstract

Background Immunotherapy targeting PD-1 provides a limited survival benefit in patients with unresectable advanced or recurrent gastric cancer (GC). Beside PD-L1, the expression of inhibitory ligands such as CEACAM-1 and LSECtin on GC cells account for this limitation. Here we assessed their expression and immune suppressive effect in GC patients. Methods Using multiplexed immunohistochemistry staining, we evaluated the distribution of different inhibitory ligands, including PD-L1, CEACAM-1, LSECtin, and MHC class II, in 365 GC patients. We analyzed their correlations and overall survival (OS) based on the expression of each inhibitory ligand and the independent prognostic factors that affect OS. Subsequently, we evaluated the additive effect of anti-PD-1 mAb or anti-PD-L1 mAb with/without anti-Lag-3 mAb with/without anti-Tim-3 mAb in cytotoxic assay using tumor-antigen specific CTL clones against GC cell lines. Results Co-expression of the inhibitory ligands for PD-1, Tim-3, and Lag-3 was observed in the largest proportion (34.7%). CEACAM-1, LSECtin, and MHC class II expression showed significant correlation with PD-L1 expression and OS. Multivariable analysis demonstrated that CEACAM-1 low is an independent prognostic factor. Furthermore, combining dual and triple ICIs yielded additive effect on cytotoxicity of CTL clones against each immune inhibitory ligand positive GC cell lines. Conclusions Our findings suggested that the expression of inhibitory ligands for Tim-3 and Lag-3 on GC cells serve as potential biomarkers to predict the response to anti-PD-1 therapy and the combinatorial immunotherapy with ICIs targeting for PD-1, Tim-3, and Lag-3 has a therapeutic potential for GC patients.

Efficacy and predictive biomarkers of immunotherapy in Epstein-Barr virus-associated gastric cancer

“… 41 Another recent study reported that combining anti-PD-1 and anti-TIM-3 mAb had an additive effect on the cytotoxicity of cytotoxic T lymphocytes, suggesting the dual-ICB targeting for PD-1 and TIM-3 as a means of increasing response rates in GC. 42 Based on these findings, triple blockade therapy targeting PD-1, CTLA-4, and TIM-3 might be a rational approach to benefit the patients with EBVaGC with the high density of CTLA-4 + and TIM-3 + cells.…”

CD3D Is an Independent Prognostic Factor and Correlates With Immune Infiltration in Gastric Cancer

“…Multiple studies have shown that TILs are often associated with better treatment response and prognosis ( 21 – 23 ). However, due to the heterogeneity of gastric cancer and the complexity of the immune microenvironment, PD-L1-based immune checkpoint inhibitors have limited benefits in the treatment of gastric cancer ( 24 ). Moreover, TILs have also been found to play a limited role in the prognosis and efficacy prediction of gastric cancer.…”

Immune Checkpoint LAG3 and Its Ligand FGL1 in Cancer

“…In ovarian cancer, interleukin (IL)6/10 and tumor-associated antigen-presenting cells (APCs) can significantly promote the co-expression of LAG3 and PD1 on the surface of CD8 + tumor-infiltrating lymphocytes ( 32 ). In gastric cancer, the inhibitory ligands of LAG3, LSECtin, and MHC II are correlated with the expression of PD-L1, which may be indicative of the OS of patients with gastric cancer ( 33 ). The dual or triple positive expression of immune checkpoints may affect tumor prognosis or treatment.…”

“…In FGL1 + gastric cancer, where a higher expression of FGL1 is positively associated with gastric cancer stage and lymph node metastasis, as well as the poor OS ( 44 ). In addition, MHC II and LSECtin, both are the ligands of LAG3, indicating a favorable survival in gastric cancer, and predict the treatment response to combination therapy with anti-PD1 and anti-LAG3 ( 33 ).…”