MMP9 and neoplasm: As described in our previous study, our group purified ganoderic acid Me (GA-Me), a natural bioactive compound from G. lucidum, and showed that it induced HCT116 cell apoptosis by upregulating p53, Bax and caspase-3 (16, 17), suppressed tumor invasion by inhibiting MMP2 and MMP9 expression (11), and inhibited tumor growth and lung metastasis by increasing interleukin-2 (IL-2)/interferon-γ (IFN-γ) expression and activating immune natural killer (NK) cells (12).