Soy compounds may offer colon cancer protection
Scientists from the Children’s Hospital & Research Center Oakland report that compounds called sphingadienes may be behind the potential anti-cancer effects of soy, long touted in scientific studies.
“It’s very exciting,” said the study’s lead researcher Dr Julie Saba. “We are encouraged to find a natural molecule that could be consumed through soy products as a strategy to help prevent colon cancer.”
Writing in the journal Cancer Research Dr Saba and her co-workers showed the effectiveness of the compounds in a mouse model of colon cancer. Their results suggest, they said, that eating more soy products may “provide protection against colon cancer in humans”.
“However, studies that specifically address the efficacy of sphingadienes in preventing colonic tumours are needed to confirm this,” they added.
How does it work?
The Oakland-based scientists report that their studies showed that the compounds could promote programmed cell death, or apoptosis, in mutant cells in a fly and a mouse.
Apoptosis is one of the body's most effective defense mechanisms against cancer. Cells are constantly checking their "normal status", and are poised to commit suicide at the first sign of irregularities, thus protecting the host from propagation of abnormal cells that can, over time, form tumours. Virtually all cancers have found ways to undermine this defense mechanism, and activation of a pathway called the Akt pathway is one of them – the pathway promotes cell growth and survival.
Their results indicated that the sphingadienes may block Akt signalling and promote cell death.
Whether other components of soy are also beneficial in fighting colon cancer is not known, said Dr Saba, and further research is necessary. “[In the meantime], I would be comfortable recommending soy products as a change in the diet that could protect against cancer. The more that soy is studied, the more of these protective agents are found, so it’s a very healthy diet choice,” she said.
Additional research is also needed to identify the best delivery methods, and the effects of a prolonged intake of the compounds, said the researchers.
Two research grants have been obtained to continue the research, and Dr Saba also hopes to determine if SDs are effective in protection against other cancers.
Source: Cancer Research
Published online ahead of print, doi: 10.1158/0008-5472.CAN-09-2341
“Natural Sphingadienes Inhibit Akt-Dependent Signaling and Prevent Intestinal Tumorigenesis”
Authors: H. Fyrst, B. Oskouian, P. Bandhuvula, Y. Gong, H.S. Byun, R. Bittman, A.R. Lee, J.D. Saba
