MMP9 and medulloblastoma: Gelatinase B/MMP-9 inhibitory siRNA inhibits gelatinase B/MMP-9 expression and tumorigenicity in a model of medulloblastoma [325] and miR-491-5p, miR-885-5p and miR-211 inhibit gelatinase B/MMP-9 expression and involvement in models of human glioblastoma [17,18].