STAT3 and neoplasm: MDSCs have been demonstrated to promote tumor sphere formation, cell colony formation, and the accumulation of CSCs in epithelial ovarian cancer by inducing the CSF2/p-STAT3 signaling pathway; notably, the maintenance of stemness in epithelial ovarian cancer cells by MDSCs can be effectively reversed by depleting CSF2 or using a p-STAT3 inhibitor (110).