Moreover, aberrant Notch signaling was reportedly related to tumorigenesis, self-renewal of CSCs and metastasis in various human tumors [24], and its downregulation was found to inhibit HCC cell invasion through inactivation of matrix metalloproteinase 2 (MMP-2), MMP-9 and vascular endothelial growth factor (VEGF) [25]. This evidence concerns the gene MMP9 and hepatocellular carcinoma.