TLR4 and non-small cell lung carcinoma: Studies on the role of TLRs in NSCLCs show that activation of TLR-4 in NSCLC cells leads to increased regulation of pro-inflammatory cytokines and chemokines (TNF-α or CCL2), which contribute to the immunosuppressive nature of the tumor microenvironment [36,37,38,39,40,41].