IFNG and neoplasm: Beside the classical activation program (known as the M1 program), which can be induced by lipoplysaccharide (LPS) or interferon-γ (IFN-γ), macrophages may engage different types of alternative activation programs (known as M2 programs) that were shown to favor tissue repair, to dampen acute inflammation or, in the case of tumor-infiltrating macrophages, to support tumor outgrowth [13], [14], [20].