TGFB1 and melanoma: In a murine melanoma lung metastasis model, researchers have observed that resident AMs maintain the expression of a mixed pro-inflammatory/anti-tumor gene profile over time as the lesion grows, including upregulation of pro-inflammatory genes, such as IL-12β, IL-1α, and IL-1β, and also anti-inflammatory genes, including Smad3 of the TGF-β signaling pathway, and a considerable downregulation of the inhibitory Smad, Smad7 from the early to the late stage [57].