Iron chelation inhibits cancer cell growth and modulates global histone methylation status in colorectal cancer.

Colorectal cancer (CRC) is one of the most common malignancies worldwide, and new treatment strategies for CRC are required because of the existing chemotherapy resistance. Iron chelators, which have been used widely for the treatment of iron-overload disease, were reported to exert anti-proliferative effects in cancer. However, the role of iron chelation in CRC was largely unknown. In this study, we found that the iron chelator DFO inhibited CRC cell growth significantly. In addition, the gene expression profile was greatly changed by DFO treatment, and many cell growth-related genes were dysregulated. Further study showed that DFO induced a significant increase in global histone methylation in CRC cells. However, the levels of histone methyltransferases and histone demethylases did not change in response to DFO treatment, implying that the enzymatic activity of these enzymes might be regulated by iron chelation. In conclusion, this study reveals a novel role for DFO in CRC cell growth, and is the first to demonstrate that global histone methylation is modulated by iron chelation in CRC cells.