MMP9 and cancer: Our analysis of XLD and glioblastoma multiforme system revealed that JUN, TP53, MMP9, PCP4, CDKN1A and TNFAIP6 proteins are the core proteins of XLD in the treatment of glioblastoma multiforme, and KEGG enrichment analysis revealed that these proteins regulate the development of glioblastoma multiforme mainly by regulating cellular senescence, transcriptional misregulation in cancer and affecting the cell cycle.