B cell-derived GABA promotes monocyte differentiation into IL-10(+) macrophages, an anti-inflammatory subtype, to limit anti-tumor immunity by inhibiting CD8(+) T cell killer function (133), establishing a suppressive TIME via modulating macrophages differentiation.GABA(B) receptor activated by tumor-derived GABA inhibits GSK-3β activity, enhances β-catenin signaling, and leads to stimulation of tumor cell proliferation and suppression of CD8(+) T cell intratumoral infiltration (137). This evidence concerns the gene GSK3B and neoplasm.