MMP9 and myxofibrosarcoma: In a subset common cohort of 40 primary myxofibrosarcomas yielding informative scoring results (Table S6, Figure S4), we further corroborated the in vitro findings in clinical samples that MTAP protein deficiency was highly associated with increased Ki-67 labeling index (p < 0.001), microvessel density (p = 0.002) assessed by CD31 staining [18], and MMP-9 expression levels (p < 0.001) evaluated by H-score method [19].