β-enolase (ENO3) is a metalloenzyme that functions during glycolysis and has been revealed ectopic expression in different cancers. However, the function and underlying modulatory mechanisms of ENO3 in hepatocellular carcinoma (HCC) are still elusive. Here, we discovered that ENO3 was remarkably down-regulated in human HCC tissue in contrast to those in noncancerous tissue. Moreover, low expression of ENO3 was related to the poor prognosis of HCC patients. Overexpression of ENO3 suppressed proliferative, migratory, and invasive abilities of HCC cells both in vitro and in vivo, whereas knocking down ENO3 led to the opposite effect. In addition, we revealed that ENO3 repressed the epithelial-mesenchymal transition (EMT) process with its biomarker variations. Mechanistic research unveiled that ENO3 suppressed the Wnt/β-catenin signal, which subsequently modulated the transcription of its target genes associated with the proliferation and metastasis capacity of HCC cells. Taken together, our study uncovered that ENO3 acted as a tumor inhibitor in HCC development and implied ENO3 as a promising candidate for HCC treatment.

High aggressiveness is the main reason for the poor prognosis of hepatocellular carcinoma (HCC) patients. However, its molecular mechanisms still remain largely unexplored. ACADL, a mitochondrial enzyme that facilitates the primary regulated step in mitochondrial fatty acid oxidation, plays a role in HCC growth inhibition. However, the function of ACADL in tumor metastasis is not well elucidated. We found that the reduced expression of ACADL is closely associated with the loss of tumor encapsulation, extrahepatic metastasis, and poor prognosis in HCC patients. Upregulation of ACADL significantly inhibited HCC migration and invasion ability. Whereas knockdown of ACADL markedly enhanced cell invasive capability. Expression of matrix metalloproteinase-14 (MMP14) was negatively associated with the content of ACADL in HCC specimens. MMP14-positive patients with a low expression of ACADL showed worse outcome. Treatment with MMP14 agonist reversed the inhibitory effect of ACADL on HCC metastasis. In addition, ACADL negatively regulated MMP14 expression by inhibiting the STAT3 signaling pathway, as the sustained activation of STAT3 effectively restored the level of MMP14 in ACADL-overexpressed cells. Collectively, these findings disclose that ACADL represses HCC metastasis via STAT3-MMP14 pathway. This study may propose a promising strategy for the precise treatment of metastatic HCC patients.