Processed tomato powder or paste, the unheralded substances found in everything from cheesy potato chips to frozen pizza, might have a new attribute: cancer fighters.
In a study to be published in the June issue of Cancer Research, three University of Missouri researchers show what they believe is exciting new evidence linking a sugar found in dehydrated tomato products to slowing the growth of prostate cancer.
They warn the research is preliminary and has only been shown effective in rats, but even the possibility of a natural way to fight the cancer found in 80 percent of men at the time of their death has researchers excited.
"If a tumor is aggressive and grows rapidly, no diet will help - you need radical therapy - but for prostate cancer, usually it happens in old age and not too many patients actually die from it," said Valeri Mossine, assistant professor of biochemistry and a primary investigator on the study. "So for those reasons, cancer prevention through food ingredients is really attractive."
For decades, epidemiologists - scientists who study the health of populations - have known that people who live near the Mediterranean Sea tend to have lower rates of prostate cancer than the rest of the world. It was widely believed that this was a result of diets rich in tomato products.
Until recently, though, most people thought tomatoes were healthy because of lycopene, the antioxidant that gives tomatoes a bright red color. Lycopene is found in healthy prostate tissue, and many health stores began selling lycopene supplements.
But in 2003, research led by John Erdman of the University of Illinois partially disproved this theory. It showed that, in rats, pure lycopene is only slightly better than nothing at all at preventing death from prostate cancer. Rats that received tomato powder had a higher survival rate.
That's where Mossine and fellow MU researchers Thomas Mawhinney and Pankaj Chopra came in. They received a grant from the Prostate Cancer Foundation to test some of the modified sugars that occur in tomatoes when heated.
Mossine said the idea that sugar could fight cancer required a leap of faith. "The idea at that time was, in order to be an anti-tumor compound you needed something toxic to kill cancer cells," he said. "We had to get through this psychological barrier."
For the past three years, the scientists have tested about 15 different sugars found in processed tomatoes. Ultimately, they stumbled upon a sugar known as Fru-His. Mossine and the other researchers tested it on four groups of rats injected with chemicals that cause prostate cancer over the course of 51 weeks. The results were encouraging:
? 60 percent of the control group developed prostate tumors.
? 30 percent of the rats fed tomato powder had prostate tumors.
? 25 percent of rats fed only tomato paste had prostate tumors.
? 10 percent of rats fed a mixture of tomato paste and pure Fru-His developed tumors.
Mossine believes he has evidence to warrant a clinical trial of Fru-His in humans. He cautioned that there are hundreds of other sugars in tomatoes that should be tested, and the best cancer-fighting effect likely comes from the "synergy" that occurs when they interact with lycopene in processed tomatoes.
Reach T.J. Greaney at (573) 815-1719 or firstname.lastname@example.org.
This page has been revised to reflect the following correction
SECOND THOUGHTS: Saturday, May 31, 2008
A news story yesterday about the cancer-fighting benefits of tomato paste
incorrectly referred twice to Valeri Mossine as "Gossine."