Glycolysis, a new mechanism of oleuropein against liver tumor.

BACKGROUND

Benign and malignant liver tumors are prevalent worldwide. However, there is no effective and comprehensive treatment option for many patients with malignant tumors. Thus, it is critical to prevent benign tumors from worsening, increasing the number of treatment options and effective medications against malignant liver tumors. Oleuropein is a natural and non-toxic product and inhibits tumor growth in various ways.

METHODS

We employed bioinformatics analysis and molecular docking to identify potential targets of oleuropein. Surface plasmon resonance (SPR) was used to determine the direct binding strength of the target and compounds. Essential functionalities of the targets were analyzed using gene interference approaches. Transcriptomic studies were performed to observe the global genomic alterations occurring inside cells. Changes in glycolytic metabolites and gene and protein expressions were also detected. The anti-tumor benefits of oleuropein in vivo were determined using a tumor-bearing mouse model.

RESULTS

Glucose-6-phosphate isomerase (GPI) was found to be a direct target of oleuropein. GPI discontinuation in liver tumor cells altered the expression of many genes, causing glycogenolysis. GPI interference was associated with PYGM and PFKFB4 inhibitors to inhibit glycolysis in liver tumors. Oleuropein inhibited glycolysis and showed good anti-tumor activity in vivo without adverse side effects.

CONCLUSIONS

GPI is a crucial enzyme in glycolysis and the immediate target of oleuropein. GPI expression inside tumor cells affects different physiological functions and signal transduction. Oleuropein has depicted anti-tumor action in vivo without harmful side effects. Moreover, it can control tumor glycolysis through GPI.