PTGS2 and hepatocellular carcinoma: The expression of cyclooxygenase‐2 (COX‐2) is associated with the M2 macrophage marker CD163/CD206 in tissue chips and paraffin sections of HCC patients and inhibits the synthesis of IFN‐γ and granzyme B+ from activated CD8+T cells via the TGF‐β pathway, which results in the loss of CD8+T cells' ability to fight tumors.21