A compound in garlic shrinks tumors from human colon cancer cells transplanted into mice, a Penn State study has found.The finding adds to a growing body of evidence that garlic can suppress human cancer cells in lab cultures and in test animals. Speaking at Experimental Biology '95, a meeting of 18 scientific societies, Penn State researcher Sujatha Sundaram described how diallyl disulfide (DADS) -- an oil-soluble sulfur compound in processed garlic -- shut down or killed human colon cancer cells in mice.
Sundaram is a doctoral student in nutrition, and her co-researcher is John Milner, head of the Nutrition department at Penn State.
In the study, mice with transplanted tumor cells from human colon cancer (one of the most common human cancers) were treated with 1 milligram of DADS dissolved in corn oil three times a week for three weeks. The treatment shrank tumors started by the cells by 60 percent. By contrast, similar tumors grew steadily in mice treated with just corn oil.
The researchers think the anti-tumor effect of DADS relates to its ability to alter cancer-cell sulfur compounds linked to cell division. This change in mineral balance likely contributes to a shutdown of cell growth, Milner says.
In previous research, Sundaram and Milner described how DADS killed tumor cells grown in lab cultures of human colon, lung, and skin cancers. "Our latest study confirms these earlier observations about DADS and related oil-soluble compounds in garlic," Milner says. "We extended use of DADS from lab cultures to animals and it still suppressed tumors."
Also at the Experimental Biology '95 meeting, Milner and colleagues described how a water-soluble substance in processed garlic, S-allylcysteine (SAC), inhibited both a carcinogen's binding to rat breast cells and the incidence of breast tumors in rats. This is the second carcinogen that Milner has shown is inhibited from binding to rat breast cells by SAC.
"Our body of research indicates that there is more than one mechanism by which garlic compounds can inhibit either carcinogen-induced tumors or cancer cell growth," Milner said.
"There is epidemiological evidence that links garlic consumption with a lower risk of colon cancer," he said. "Our latest studies support these findings. It appears that garlic can be beneficial in therapies that either prevent or treat chemically induced cancers."
(Author: Scott Turner, Penn State Department of Public Information)
Return to Health and Human Development On-Line Magazine
