PTGER4 and colorectal carcinoma: Compared with healthy tissue, nine genes were upregulated between onefold and twofold in the CRC group: MMP1, MMP7, MMP9, WNT5A, IL-6, PTGS2, MYC, BIRC5, and CCND1. Seven genes upregulated between 0.5-fold and onefold: AXIN2, VEGFA, TLR2, STAT1, LEF1, MEH2, and TLR4. The downregulated genes (0.5-fold to 1.0-fold) include IL-6R, TLR3, PIGER2, MAP2K6, ARRB1, PTGER4, CDKN1A, MAPK3, and TLR7. The DEG expression heat map is shown in Figure 3.