CCL2 and neoplasm: Among the nearly 300 differentially expressed secreted chemokines and cytokines (Additional file 2: Table S1), we found that Cxcl2, Cxcl5, Ccl2, Ccl3, Ccl5, Ccl8, Csf1, Csf2, and Csf3 were among the top up-regulated secreted factors (Fig. 6h), it has been widely reported that Ccl2, Ccl5 and Csf1 can promote the recruitment of macrophages in tumor sites, Csf1 also can induce tumor-associated macrophages to polarized into M2 phenotype [46].