PTGER2 and neoplasm: First, in in vitro study, EP2 signaling synergizes with other cytokines present in the tumor microenvironment, TNF-α, to transcriptionally induce expressions of IL-6 (Il6), COX-2 (Ptgs2), and CXCL1 (Cxcl1) in primary culture of neutrophils and IL-6, COX-2, and MMP-12 (MMP12) in 18 Co cell line, an in vitro TAF model [12].