Consistent with the previous results, 4T1 cells mixed with T-exo-polarized macrophages generated larger and heavier tumors with high expression of Cd206. Pretreating macrophages with JQ1 or Ex 26-CSOPOSA/JQ1 could slow the tumor growth and down-regulate the expression of Cd206. Collectively, these results demonstrated that T-exo could induce M2 polarization of macrophages to accelerate tumor progression, and Ex 26-CSOPOSA/JQ1 could inhibit the tumor-promoting effect of T-exo by interfering with the polarization process. This evidence concerns the gene MRC1 and neoplasm.