Emodin regulated lactate metabolism by inhibiting MCT1 to delay non-small cell lung cancer progression

Lung cancer is one of the most common malignant tumors in the world, with high incidence rate and mortality. Monocarboxylate transporter (MCT) 1 has been found to be widely expressed in various tumors and plays a crucial role in regulating energy metabolism. Emodin, as an important traditional Chinese medicine in China, has been reported to inhibit the progression of lung cancer. However, its potential mechanism has not been fully elucidated. The effects of emodin and MCT1 inhibitor AZD3965 on the proliferation, migration, and invasion of lung cancer cells were detected using cell counting kit-8 (CCK-8) assay, wound-healing assay, and transwell small chamber assay. The content of glucose, lactate, and pyruvate in the cell culture medium was detected using a glucose, lactate, and pyruvate detection kit, and also detected protein expression using western blotting. In addition, to investigate the effects of emodin and AZD3965 on lung cancer in vivo, we constructed nude mice subcutaneous transplant tumor model by subcutaneous injection of lung cancer cells. The results showed that emodin and AZD3965 could inhibit the proliferation, migration, and invasion of lung cancer cells. At the same time, they could inhibit the expression of MCT1 in lung cancer cells and promote the release of lactate, but did not affect the content of glucose and pyruvate. In vivo experiments had shown that emodin and AZD3965 could effectively inhibit the growth of lung cancer and inhibit the expression of MCT1. All in all, our data suggested that emodin inhibited the proliferation, migration, and invasion of lung cancer cells, possibly by inhibiting MCT1, providing important theoretical basis for elucidating the mechanism of emodin in treating lung cancer.