In further stratified analysis, the positive staining area percentages of β-catenin and MMP7 in advanced stage NPC (III stage or IV stage) were significantly higher than those in the early stage NPC (II stage) (P < 0.05 and P < 0.01, respectively), while the III stage and IV stage were not statistically different (Table S5). The gene discussed is MMP7; the disease is nasopharyngeal carcinoma.