Folates and antifolates in the treatment of cancer; role of folic acid supplementation on efficacy of folate and non-folate drugs

Folates are essential nutrients for the cell for DNA synthesis. From a nutritional perspective, a high folate status may have a beneficial/protective effect against cancer, birth defects and age-related diseases. However, data presented in this study provide evidence that a high folate status can also have a differential impact on the therapeutic efficacy of both folate-based and other widely used anticancer agents. This study describes the molecular mechanisms underlying these effects, which involve folate influx/efflux proteins, intracellular metabolism and target enzymes.