The polarization of TAMs from an anti-tumoral M1 phenotype to a pro-tumoral M2 phenotype by PEGylated liposomes has been reported.136 PEGylated liposomes have shown a pro-tumoral effect in an immunocompetent mice model, subcutaneously implanted with TC-1 cells.131 The pro-tumoral effect is attributed to the suppression of Th1 cytokine (IFN gamma) and low CTLs in the tumour tissue as compared to vehicle control. This evidence concerns the gene IFNG and neoplasm.