MMP9 and ovarian cancer: In the context of the complex molecular interplay between ovarian cancer cells and TAMs, the metastatic microenvironment in the intraperitoneal cavity is modulated by a plethora of soluble signaling molecules, including IL-6, IL-8, IL-10, TGF-β, CCL18, CCL22, SDF-1α, VFGF, MMP-9, and heparin-binding EGF (HB-EGF) [90, 92, 103–105].