Fig. 3
The overview of aberrant tumor lactate-related metabolism compared to physical conditions. In TME, cancer cells exhibit increased tumor glycolysis to meet their high energy demands and metabolic needs. This heightened glycolysis leads to elevated glucose consumption, resulting in excess lactate production and reduced ATP production in the cytoplasm. In normal cells, glycolysis involves ten steps, with the end product pyruvate entering the mitochondria for energy production via the TCA cycle. Besides participating in glucose metabolism, about 10% of the pyruvate is involved in other types of metabolism such as protein metabolism. Failure of pyruvate to enter the TCA cycle leads to decreased energy production compared to glucose molecules through altered glycolysis. Lactate in TME plays a crucial role in regenerating NAD+ molecules and directly join the TCA cycle under hypoxic conditions to sustain glycolysis and ATP production. In addition to glucose metabolism, increased glutaminolysis and lipogenic enzymes expression are also observed in TME. Generated using Adobe Illustrator (Version 28.2). Abbreviations: GLUT1/4 glucose transporter 1/4, TME tumor microenvironment
