The role of NFATc1/c-myc/PKM2/IL-10 axis in activating cervical cancer tumor-associated M2 macrophage polarization to promote cervical cancer progression

Abstract

Nuclear factor of activated T cells 1 (NFATc1) is mainly expressed in tumor microenvironment, especially in macrophages. However, whether NFATc1 is involved in the polarization of tumor associated macrophages (TAMs) and tumor progression in cervical cancer (CC) remains unclear. Immunofluorescence staining was used to detect the expression of CD68 and NFATc1 in CC tissues or adjacent normal tissues of patients. RT-qPCR, flow cytometry, ELISA, and inhibitors treatment were used to observe the effect of NFATc1 on TAMs polarization. Clonal formation, scratch, and transwell assays were used to examine the effects of NFATc1-transfected macrophages or NFATc1-transfected TAM on tumor proliferation, migration, and invasion. Further, a xenograft model was established to confirm the roles of NFATc1+ TAM in CC tumorigenesis. NFATc1+CD68+/CD68+ TAMs ratio was significantly increased in CC tissues compared with the normal tissue, and NFATc1+ TAM showed an M2-like TAM subtype. NFATc1 induced macrophages to secrete IL-10, which further induced M2 polarization of macrophages. Mechanically, the c-myc-PKM2 pathway mediated the expression of IL-10 in NFATc1-induced macrophages. Functionally, NFATc1 induced M2 macrophages promoted the proliferation, migration, and invasion of CC cells, and the knockout of NFATc1 in TAMs significantly inhibited the tumor-promoting function of TAMs. Further, the tumorigenesis test in nude mice confirmed that NFATc1+ TAM promoted the tumorigenicity of CC cells in vivo. In conclusion, NFATc1 mediated IL-10 secretion by regulating the c-myc/PKM2 pathway, thereby inducing M2 polarization of TAMs and promoting the progression of CC.