ICAT-Mediated Crosstalk Between Cervical Cancer Cells and Macrophages Promotes M2-Like Macrophage Polarization to Reinforce Tumor Malignant Behaviors.

Inhibitor of β-catenin and T-cell factor (ICAT) is a classical inhibitor of the Wnt signaling pathway. Nonetheless, our previous work found that ICAT is overexpressed in cervical cancer (CC), resulting in the augmentation of migration and invasion capabilities of CC cells. It remains unclear what molecular mechanism underlies this phenomenon. The interaction between cancer cells and the tumor microenvironment (TME) promotes the outgrowth and metastasis of tumors. Tumor-associated macrophages (TAMs) are a major constituent of the TME and have a significant impact on the advancement of CC. Consequently, our inquiry pertains to the potential of ICAT to facilitate tumor development through its modulation of the cervical TME. In this study, we first verified that ICAT regulated the secretion of cytokines interleukin-10 (IL-10) and transforming growth factor-β (TGF-β) in CC cells, leading to M2-like macrophage polarization and enhancement of the migration and invasion of CC cells. Furthermore, the system of co-culturing human umbilical vein endothelial cells (HUVECs) with macrophages revealed that depending on the CC cells' overexpression or inhibition of ICAT, the vascular tube formation by HUVECs can be either increased or decreased. Overall, our study indicates that ICAT stimulates M2-like polarization of TAMs via upregulating IL-10 and TGF-β, which results in increased neovascularization, tumor metastasis, and immunosuppression in CC. In upcoming times, inhibiting crosstalk between CC cells and TAMs may be a possible strategy for CC therapy.