MMP9 and hepatocellular carcinoma: Furthermore, analyzed with Pearson correlation analysis, a significant positive correlation between circUBAP2 and MMP9 was detected (r = 0.8585, P < 0.001), while the correlation between miR-194-3p and MMP9 was negative (r = −0.6844, P < 0.001) in 60 HCC cases (Figures 5D,E).