FIGURE 9.

A model of CCCTC‐binding factor (CTCF)‐controlled prostaglandin‐endoperoxide synthase 2 (PTGS2) expression in tumour‐associated macrophages (TAMs) in the pancreatic ductal adenocarcinoma (PDAC) tumour microenvironment. CTCF forms a complex with the cis‐regulatory long noncoding RNA‐PTGS2 antisense NF‐κB1 complex‐mediated expression regulator RNA (LncRNA‐PACERR) in the PTGS2 promoter region and recruits E1A binding protein p300 (EP300), to enhance chromatin accessibility and promote the transcription of PTGS2, thereby inducing M2 polarization and pro‐tumour functions of TAMs