Tumor ß-catenin expression is associated with immune evasion in non-small cell lung cancer with high tumor mutation burden.

ß-catenin expression by tumor cells suppressed dendritic cell recruitment to the tumor microenvironment in a melanoma model, resulting in fewer tumor-infiltrating lymphocytes. Immunohistochemistry was used in the present study to examine the association between the expression of ß-catenin and tumor infiltrating lymphocytes and CD11c+ cells in 122 patients with non-small cell lung cancer (NSCLC), who underwent radical surgery. ß-catenin was positive in 24% of NSCLC tumors compared with 59% of squamous cell carcinomas and 11% of adenocarcinomas. There was no significant association between the expression of ß-catenin and the frequency of CD8+ cell infiltration into tumor tissues, including the stroma. Conversely, the infiltration of CD8+ cells into tumor nests was significantly lower in ß-catenin-positive cases compared with that in negative ß-catenin cases. Similarly, CD11c+ cell infiltration was significantly lower in the ß-catenin-positive group. The ß-catenin-positive group had shorter overall survival and recurrence-free survival times compared with that in the negative group. Furthermore, ß-catenin-positive NSCLC had a high tumor mutation burden, but tended to have a low expression of programmed death-ligand 1. In conclusion, the expression of ß-catenin in NSCLC was negatively associated with CD11c+ cells and cytotoxic T cell infiltration at the tumor site and had a tendency towards a poor prognosis.