MTHFD2 and malignant colon neoplasm: Therefore, they showed that the anti-cancer effect of TH9619 is the result of the accumulation of 10-formyl-THF as a consequence of MTHFD1 inhibition while mitochondrial MTHFD2 is still active, causing a folate trap that provokes cell death in breast and colon cancer cells due to thymidylate depletion.