Using murine and human tumor cells with typical features of EMT, high motility and invasivity, following transduction of a cDNA coding for snail family zinc finger 1 (Snail), we found that Snail+ metastatic tumor cells specifically release a large amount of TSP1 (Kudo-Saito et al., 2009), CCL2 (Kudo-Saito et al., 2013b), and FSTL1 (Kudo-Saito, 2013; Kudo-Saito et al., 2013a), all of which can generate immune suppression and dysfunction mediated by immunoregulatory cells including CD4+Foxp3+ Tregs, CD11c+MHC IIlow/− DCregs and CD45−ALCAM+ MSCs, and functionally impaired CD8low T cells. This evidence concerns the gene SNAI1 and neoplasm.