Many of them, such as ATAD2, ATR, BRCA2, CSDE1, CSMD3, DLC1, EGFR, ELF3, ERBB4, FGFR2, KLF5, TRPA1, TSHZ2, GNAS, MYC, and MMP9 for MSS tumors and ATM, CDC27, ESR1, KMT2E, and NEB for MSI tumors, have been previously identified as drivers by TCGA/non-TCGA studies for other cancer types but not for gastric cancer. Here, MMP9 is linked to gastric cancer.