FPR2 Participates in Epithelial Ovarian Cancer (EOC) Progression Through RhoA Mediated M2 Macrophage Polarization: An Invitro Experimental Study

Abstract

Background: In our previous study, we found Formyl peptide receptor 2 (FPR2) promoted the invasion and metastasis of EOC and it could be a prognostic marker for EOC. In this study, we aimed to study the possible mechanism of FPR2 in promoting EOC progression.Methods: The FPR2 ectopic expression and knockdown EOC cell lines as well as their control cell lines were established and the expression change of RhoA in each cell lines was evaluated by RT-qPCR and Western-blot. Wound healing and Transwell assays were performed to detect the migrational ability of EOCs that affected by FPR2 and RhoA. The supernatant of each EOC cell lines were used to co-culture with the macrophages, and tested the M1 and M2 macrophges biomarkers by flow cytometry. THP-1 cell line was also indcued to differentiated to M1 and M2 macrophages, FPR2 and RhoA expression in each macrophage cell lines were detected by RT-qPCR and Western-blot. Results: RhoA expression was significantly increased in EOCs along with the overexpression of FPR2, which showed a positive correlation by Pearson correlation analysis. FPR2 ectopic expression would contribute to the migrational ability of EOCs, and RhoA inhibitor (C3 transferase) would impare EOCs migration. Furthermore, FPR2 stimulated the secretion of Th2 cytokines by EOCs, which induced macrophages differentiate to M2 phenotype, while RhoA inhibitor stimulate the secretion of Th1 cytokines and induce macrophages differentiate to M1 phenotype. Moreover, compared with M1 macrophages and THP-1 cells, FPR2 and RhoA expression were significantly up-regulated in M2 macrophages.Conclusion: FPR2 stimulated M2 macrophage polarization and promote invasion and metastasis of ovarian cancer cells through RhoA.