Myeloid-Derived Suppressor Cells Infiltration in Non-Small-Cell Lung Cancer Tumor and MAGE-A4 and NY-ESO-1 Expression

Cancer/testis antigens melanoma‑associated antigen 4 (MAGE‑A4) and New York esophageal squamous cell carcinoma‑1 (NY‑ESO‑1) are of clinical interest as biomarkers and present valuable targets for immunotherapy; however, they are poor prognostic markers in non‑small cell lung cancer (NSCLC). In addition, myeloid derived suppressor cells (MDSCs) are recognized as a key element in tumor escape and progression. The aim of the present study was to investigate the diagnostic and prognostic value of MAGE‑A4 and NY‑ESO‑1, and their association with MDSCs in NSCLC samples. The expression levels of MAGE‑A4 and NY‑ESO‑1, and the infiltration of MDSCs (CD33+), were analyzed by immunohistochemistry of 67 tissue samples from patients with NSCLC. Overall, 58.33% of the NSCLC squamous cell carcinoma tissues and 94.7% of adenocarcinoma tissues were positive for MAGE‑A4. NY‑ESO‑1 expression was observed in 52.78% of the squamous cell carcinoma tissues and 80% of the adenocarcinoma tissues. In primary adenocarcinoma tumor tissues, MAGE‑A4 and NY‑ESO‑1 demonstrated a higher intensity of expression compared with the squamous cell carcinoma tissues. A total of 33 (91.7%) squamous cell carcinoma and 19 (95.0%) adenocarcinoma specimens were positive for CD33. The expression of MAGE‑A4 and NY‑ESO‑1 antigens and infiltration of MDSCs was associated with poor prognosis of patients with NSCLC. Further studies investigating the association between these findings and underlying molecular mechanisms are required