The effect of folic acid and its metabolites on human colorectal cancer cells

Abstract

In the United States, colorectal cancer (CRC) is the third leading cause of death from cancer. Promising research has shown the chemopreventive effects of folic acid (FA) on CRC. Folate is a water-soluble B vitamin that is essential in the transfer of one-carbon necessary for DNA synthesis and methylation reactions. Because folate is essential in DNA replication, a deficiency can predispose cells to neoplastic transformation. While folate depletion in normal tissues can predispose them to becoming cancerous, researchers discovered that folate depletion in colon cancer cells might suppress the progression of current neoplasms, decreasing cell proliferation. The current study investigated the role of FA and its metabolites on CRC cell proliferation, apoptosis, cell cycle regulation and metastasis. We demonstrated that FA did not regulate proliferation in several different colon cancer cell lines. FA did not influence cell cycle regulation, apoptosis or metastasis in HCT116 cells. In addition, we observed that FA decreased expression of proteins involved in epithelial-mesenchymal transition (EMT) in A549 lung cancer cells. Metabolites of FA, including dihydrofolic acid (DHF) and tetrahydrofolic acid (THF), did not significantly affect HCT116 cell proliferation or cell cycle regulation. This study suggests that FA and its metabolites do not regulate colon cancer. Further studies are warranted to investigate the potential role of FA in lung cancer EMT.