Differential Expression of Novel Immune Checkpoint Receptors on Tumor Infiltrating Lymphocytes in Patients with Locally Advanced Breast Cancer after Neoadjuvant Chemotherapy.

Immune checkpoint receptors (ICRs) were recently found to modulate the anti-tumoral immune response. This study aimed to determine the clinical and pathological associations of ICRs expression on tumor-infiltrating lymphocytes (TILs) in patients with locally advanced breast cancer (LABC) treated with neoadjuvant chemotherapy (NAC). Expressions of ICRs including PD-1, LAG-3, TIM-3, TIGIT, and CTLA-4 on CD8+ T lymphocytes and Natural Killer (NK) cells on TILs were analyzed by flow cytometry.