The immunosuppression induced by the HCMV infected tumor cells through secretion of GM-CSF [82], and other immunosuppressive mediators such as TGF-β and cmvIL-10 [54, 55], creates a tumor micro-environment that protects the productively infected cells from destruction by disarming NK-cells and impairing the CD8+ cytotoxic T cell mediated tumor elimination (Figure 4) [56, 57]. This evidence concerns the gene CSF2 and neoplasm.