SAT-197 Functional Cross-Talk Between MCP-1 and Integrin Linked Kinase Is Required for Endometriosis Disease Progression

Development of painful invasive endometriotic lesions is usually a combined function of the chronic inflammation and active sequential cellular events such as migration, cell adhesion, proliferation, colonization, and invasion in endometriosis. An elevated level of monocyte chemotactic protein-1 (MCP-1) in serum and peritoneal fluid has been reported in endometriosis. Further, Integrin-Linked Kinase (ILK) communicates with extracellular signals and regulates the sequential cellular events in uterine and ovarian cancer. The functional cross-talk of MCP-1 with ILK in the immune cells leads to the high MCP-1 production and increased ILK activity. However, the role of the elevated MCP-1 level and its functional interaction with ILK in the endometriosis development is not explored yet. In order to investigate this, we used the surgically induced heterologous mouse model of endometriosis and externally treated with MCP-1 intraperitoneally for two weeks. Our results demonstrated that MCP-1 boosted the growth of endometriotic lesions mediated through ILK, FAK, VAV and RAC1 signaling axis in endometriosis. In addition, in vivo pharmacological inhibition of ILK by CPD22 restricted the growth of endometriotic lesions in mice. Flow cytometric and inflammatory cytokines profiling in the peritoneal fluid demonstrated that ILK was involved in the MCP-1 mediated macrophage(F4/80+) recruitment and inflammatory response in order to support the growth of endometriotic lesions. Inhibition of ILK induced the anti-inflammatory cytokine IL-10 and concomitantly suppressed the pro-inflammatory cytokines MCP-1, TNF-α and IL-10 levels in peritoneal fluid. In vitro studies on human ovarian cystic endometriosis cells (Hs832(C).T) and normal endometrial stromal cells (T-HESCs) revealed that MCP-1 accelerated the adhesion (on collagen and fibronectin substratum), colonization, migration and 3D-spheroids formation and invasion. As the basal level of CCR2, an MCP-1 receptor, expression was higher in ovarian endometriotic cells than the normal endometrial stromal cells giving the hint for the role of MCP-1 in endometriosis. Interestingly, the siRNA mediated knockdown of ILK renders the MCP-1 induced nuclear translocation of phosphorylated ILK and also reduced these accelerated cellular events. Taken together, our results provide compelling evidence that the functional cross-talk between MCP-1 and ILK drives endometriotic disease progression.