IL6 and central nervous system cancer: In addition, glioma stem cells were reported to activate the STAT3 signaling through secreting IL-6 and IL-10, thereby resulting in activation of B7-H4 expression in tumor-associated macrophages [30], while B7-H4 triggered the escape of glioma-initiating cells from immune surveillance in the microenvironment of gliomas through blocking effective T-cell immune responses [31], indicating that STAT3 is involved in immune escape of gliomas and promotes glioma progression.