MMP9 and neoplasm: The activation of the SRC, PI3K/AKT, and STAT3 pathway can facilitate the proliferation and growth of tumor cells by upregulating the expression of Myc, CyclinD1, and CDC2; inhibit apoptosis by upregulating BCL-xL, Survivin, and Mcl; promote metastasis by upregulating FAK, p130Cs, MMP2, and MMP9; and accelerate tumor angiogenesis by upregulating VEGF and HIF1α41–43.