Of notice, the percentage of MDSCs in B16-F1 tumours at a late stage of growth, in which A-SMase was spontaneously downregulated [18], was similar to that of B16-W6_pSIL10 tumours (Supplementary Figure 1(a) in Supplementary Material available online at http://dx.doi.org/10.1155/2015/370482). Here, SMPD1 is linked to neoplasm.