Targeting mitochondrial one-carbon enzyme MTHFD2 together with pemetrexed confers therapeutic advantages in lung adenocarcinoma.

Metabolic remodeling is the fundamental molecular feature of malignant tumors. Cancer cells require sufficient energy supplies supporting their high proliferative rate. MTHFD2, a mitochondrial one-carbon metabolic enzyme, is dysregulated in several malignancies and may serve as a promising therapeutic candidate in cancer treatment. Here, our data confirmed that MTHFD2 gene and protein was upregulated in the cancerous tissues of LUAD patients and was correlated with a poor survival in LUAD. MTHFD2 was involved in lung cancer cell proliferation, migration, and apoptosis by mediating its downstream molecules, such as DNA helicases (MCM4 and MCM7), as well as ZEB1, Vimentin and SNAI1, which contributed to tumor cell growth and epithelial-to-mesenchymal transition (EMT) process. Moreover, we identified that miRNA-99a-3p appeared to be an upstream mediator directly regulating MTHFD2 and MCM4 expression. Moreover, specific inhibition of MTHFD2 functions by siRNA or a chemical compound, improved anti-tumor sensitivities induced by pemetrexed in LUAD. Taken together, our study revealed the underlying molecular mechanisms of MTHFD2 in regulating cell proliferation and identified a novel therapeutic strategy improving the treatment efficacies in LUAD.