MMP9 and hepatocellular carcinoma: The oncogenic behavior of hepatic miR-155 was also confirmed by Yan et al. They correlated its elevation with the downregulation of SOCS1, which activated STAT3, previously confirmed as an important prognostic biomarker in other cancers, such as glioblastoma [183], and further downregulated MMP9 expression, consequently promoting HCC tumor invasiveness [184].