For example, TAMs upregulate urokinase-type plasminogen activator (uPAR) and secrete MMPs, such as MMP-9, which enable the remodelling of the ECM [98] and increase the invasiveness of melanoma, or they upregulate such factors in melanoma cells through the secretion of TNFα and IL-1α [98]. Here, MMP9 is linked to melanoma.