ENO3 promotes colorectal cancer progression by enhancing cell glycolysis

Colorectal cancer (CRC) is among the leading cause of cancer-related morbidity and mortality worldwide. Aerobic glycolysis, as a metabolic hallmark of cancer, plays an important role in CRC progression. Enolase 3 (ENO3) is a glycolytic enzyme that catalyzes 2-phosphoglycerate into phosphoenolpyruvate, while its role in CRC is still unknown.

Bioinformatics analysis was performed to examine the expression changes and roles of ENO3 in CRC patients from public databases. Then, ENO3 expression was validated in CRC tissues using Quantitative real-time PCR (qRT-PCR), immunohistochemical (IHC) analysis, and western blot. Overexpression and silencing models were constructed using plasmid and lentivirus transfection. Cell viability, proliferation, and migration in vitro were applied to evaluate the protumoral effects of ENO3 on CRC. RNA sequencing and GO enrichment analysis of differentially expressed genes (DEGs) were performed to explore the underlying molecular mechanisms of ENO3 in CRC progression. The ATP and lactate production level were detected to assess cell glycolysis.

ENO3 was significantly up-regulated in CRC. High ENO3 expression was positively correlated with poor prognosis and higher clinical stages of CRC patients. ROC curve demonstrated the diagnostic value of ENO3 for CRC with the AUC of 0.802. Gain- and loss-of function experiments demonstrated that ENO3 significantly enhanced the proliferation and migration ability of CRC cells in vitro. After ENO3 knockdown, RNA sequencing screened out a list of DEGs which were enriched in the regulation of the glycolytic process. The detection of lactate production and ATP level verified the role of ENO3 in the glycolytic process.

Our findings illustrate that ENO3 could promote the progression of CRC by the enhancement of cell glycolysis, indicating the potential value of ENO3 as a novel biomarker and therapeutic target for CRC.