Abnormal β-catenin expression and reduced tumor-infiltrating T cells are related to poor progression in non-small cell lung cancer.

OBJECTIVE: This study was to identify the relationship between the expression of β-catenin and CD8+ T cells infiltration in non-small cell lung cancer (NSCLC). METHODS: A total of 100 NSCLC patients undergoing lobectomy and lymph node dissection were enrolled in this study. The baseline demographics, histopathologic data, recurrence-free survival (RFS) period, and pathologic specimens preserved in paraffin were available for them. Immunohistochemistry (IHC) was carried out with resected, paraffin-embedded NSCLC tissues. Evaluation of tumor-infiltrating CD8+ T cells immunostaining was performed using a four-tiered scale according to the visual estimation on lymphocytes. RESULTS: A significant association was found between reduced β-catenin expression and nodal involvement (P=0.047), but no association with other characters. The RFS of patients with reduced β-catenin expression was potently worse than that of patients with preserved β-catenin expression (P=0.026). Meanwhile, no significant association was observed between depressing CD8+ T cells levels and all characters. The RFS of NSCLC patients containing low CD8+TILs was remarkably worse than those with high CD8+ T cells (P=0.003). Multivariate analysis revealed that only CD8+TILs was an independent predictor of RFS (P=0.024). Moreover, CD8+ T cells level was negatively correlated with abnormal β-catenin expression (P=0.016). CONCLUSION: Abnormal β-catenin expression might suppress antitumor activity by decreasing tumor-infiltrating CD8+ T cells. Inhibition of β-catenin expression and/or activity might be used as a component of anti-cancer immunotherapy in the future.