TLR4 and lung carcinoma: It is intriguing to note that the tumorigenesis and metastasis of different forms of lung carcinoma are principally mediated by the TLR2, TLR4, and TLR9-guided production of anti-inflammatory cytokines such as transforming growth factor-β (TGF-β), and IL-10 and growth factors such as vascular endothelial growth factor (VEGF) and fibroblast growth factor 2 (FGF2) (87).