MMP9 and ovarian cancer: To validate the GSEA results, after infection with TMEM14A-shRNA lentivirus for 48 h, protein expression of cell cycle-related (PCNA [15], Cyclin D1 and Cyclin E [16]) and metastasis-related (MMP-2 and MMP-9) regulators in both ovarian cancer cells were measured by Western blot.