CCL2 and gastric cancer: In this way, major M2-related genes Ym-1 and Fizz-1 are significantly upregulated, promoting the expression of M2-related proteins such as CD204 and CD163, inducing the secretion of IL-10, vascular endothelial growth factor (VEGF) and monocyte chemoattractant protein-1 (MCP-1) that are beneficial to tumor growth, reducing the secretion of pro-inflammatory cytokines like IFN-γ, IL-12, IL-2 and MIP-1α, which has been observed in a mouse xenograft model with gastric cancer [39].