TLR4 and neoplasm: It has been confirmed in various OSCC cell lines (CAL-27/SCC25/SCC9) that HMGB1, upon binding to TLR4, activates the NF-κB pathway, regulates macrophage polarization by upregulating the expression of IL-10 and TGF-β, and enhances the expression of PD-L1, thus promoting tumor immune escape [36, 47].