MMP9 and neoplasm: Interestingly, mechanistic studies revealed that Plasmodium-derived hemozoin that accumulated in TAMs abrogated IGF-1R signaling partly by silencing its downstream targets PI3K and MAPK, causing decreased expression of tumor angiogenesis facilitator matrix metalloprotease 9 (MMP-9) in TAMs, and in turn leading to decreased tumor angiogenesis and TAM infiltration (34).