For example, in the process of skin inflammation IFN-γ can induce the expression of CD274 mRNA in dermal fibroblast cells with NF-κB and MAPK and PI3K signaling pathways involved [27], and LPS-TLR4 interaction induces CD274 expression through MAPK pathways in bladder cancer cells [28]. Here, TLR4 is linked to urinary bladder cancer.