AICR ScienceNow
Volume 15
Winter 2006
Curcumin is the phytochemical in the spice turmeric that gives curry its yellow color. In animal studies, it has prevented the growth of several types of cancers. It has even been tested in clinical trials as a way to prevent cancer in humans.
Suzy V. Torti, Ph.D., Associate Professor of Biochemistry at Wake Forest University School of Medicine in Winston-Salem, N.C., has studied curcumin's protective effect against cancer. In collaboration with her research colleagues, Dr. Torti recently found a possible explanation for how curcumin inhibits tumor growth.
Cancer Cells Deprived of Iron
"We made the unexpected observation that curcumin binds and isolates iron in cells and tissues," says Dr. Torti. The process of binding and isolating a metal ion such as iron is known as chelation. Her group made this discovery after studying the effects of several natural products.
How chelation of iron by curcumin may prevent cancer is unknown. It may involve the special need of tumor cells for iron. Although iron is essential for the body to function, cancer cells are avid for iron. It is required for their growth and DNA synthesis. In conditions of excess iron storage, the risk of liver cancer is greatly increased.
Dr. Torti notes, however, that chelation is probably only a part of how curcumin affects tumors. "Studies have shown lots of partial answers to the question of why curcumin inhibits tumor growth. Its property of chelating iron is just another piece of the puzzle of how this simple molecule works."
Pinpointing the Relationship
In a current, two-year study, funded by AICR, Dr. Torti and her colleagues are attempting to better define the interaction between iron and curcumin and their effects on tumor growth. Her study will use mice that have a genetic defect that causes them to develop intestinal tumors. The mice will all be fed the same amount of curcumin.
In this study, Dr. Torti will see how many intestinal or liver tumors the mice develop when they are given varying amounts of iron. "We will assess whether giving more or less iron when you are also giving curcumin will affect how the curcumin works in preventing tumors," Dr. Torti says.
The study will also examine the molecular action of curcumin. This information could lay the groundwork for developing medicines or treatments that mimic the chemopreventive actions of curcumin. The other findings from this study could have important and practical implications for dietary interventions used to prevent cancer. "Our study with mice will be the first to provide some measurements of the effect of different levels of iron when curcumin is being used," Dr. Torti points out.
If dietary iron reduces the activity of curcumin, this could have immediate implications for human trials, where iron supplementation might be avoided or reduced when curcumin is administered. She concludes, "If people are taking curcumin to prevent them from getting cancer, and they are also taking iron supplements, the curcumin may be inactivated by the iron, possibly defeating the whole purpose."
Reference
Buss JL et al. The role of iron chelation in cancer therapy. Current Medicinal Chemistry. 2003;10(12):1021-34. All active news articles
Volume 15
Winter 2006
Stronger Than Iron, Curcumin May Prevent Tumors
Suzy V. Torti, Ph.D., Associate Professor of Biochemistry at Wake Forest University School of Medicine in Winston-Salem, N.C., has studied curcumin's protective effect against cancer. In collaboration with her research colleagues, Dr. Torti recently found a possible explanation for how curcumin inhibits tumor growth.
Cancer Cells Deprived of Iron
"We made the unexpected observation that curcumin binds and isolates iron in cells and tissues," says Dr. Torti. The process of binding and isolating a metal ion such as iron is known as chelation. Her group made this discovery after studying the effects of several natural products.
How chelation of iron by curcumin may prevent cancer is unknown. It may involve the special need of tumor cells for iron. Although iron is essential for the body to function, cancer cells are avid for iron. It is required for their growth and DNA synthesis. In conditions of excess iron storage, the risk of liver cancer is greatly increased.
Dr. Torti notes, however, that chelation is probably only a part of how curcumin affects tumors. "Studies have shown lots of partial answers to the question of why curcumin inhibits tumor growth. Its property of chelating iron is just another piece of the puzzle of how this simple molecule works."
Pinpointing the Relationship
In a current, two-year study, funded by AICR, Dr. Torti and her colleagues are attempting to better define the interaction between iron and curcumin and their effects on tumor growth. Her study will use mice that have a genetic defect that causes them to develop intestinal tumors. The mice will all be fed the same amount of curcumin.
In this study, Dr. Torti will see how many intestinal or liver tumors the mice develop when they are given varying amounts of iron. "We will assess whether giving more or less iron when you are also giving curcumin will affect how the curcumin works in preventing tumors," Dr. Torti says.
The study will also examine the molecular action of curcumin. This information could lay the groundwork for developing medicines or treatments that mimic the chemopreventive actions of curcumin. The other findings from this study could have important and practical implications for dietary interventions used to prevent cancer. "Our study with mice will be the first to provide some measurements of the effect of different levels of iron when curcumin is being used," Dr. Torti points out.
If dietary iron reduces the activity of curcumin, this could have immediate implications for human trials, where iron supplementation might be avoided or reduced when curcumin is administered. She concludes, "If people are taking curcumin to prevent them from getting cancer, and they are also taking iron supplements, the curcumin may be inactivated by the iron, possibly defeating the whole purpose."
Reference
Buss JL et al. The role of iron chelation in cancer therapy. Current Medicinal Chemistry. 2003;10(12):1021-34. All active news articles