MMP9 and hepatocellular carcinoma: Univariate Cox proportional hazards regression analysis revealed that seven cellular senescence-related genes were associated with the prognosis of HCC, and CDK1, CDK4, G6PD, AURKA, MMP9, IGFBP3, and CHEK1 were considered risk factors (P<0.01, HR>1) (Figure 8C).