Study: Recalled Herbal Supplement May Help Fight Colorectal Cancer

PC SPES, a Chinese herbal supplement once used by thousands of men seeking to prevent recurrence of prostate cancer, may also be a potent remedy for fighting colorectal cancer, according to UCLA researchers.

But even if this is true, it may not have any immediate relevance because the company that produced it is closed, and the supplement is no longer available in the United States.

In February 2002, the U.S. Food and Drug Administration (FDA) warned men to stop taking PC SPES and the California Health Department forced a recall of the product after tests showed that it contained various prescription drugs.

A group of researchers led by Dr. Robert Nagourney of Rational Therapeutics in Long Beach, California subsequently reported in the Journal of the National Cancer Institute that chemical analyses if batches of PC SPES detected "various amounts of the synthetic drugs diethylstilbestrol (a potent estrogen), indomethacin (an analgesic), and warfarin (a blood thinner)."

Prescription drugs are not allowed as part of the mix of unregulated herbal products.

Now, in the journal Cancer Research, UCLA researchers report on what they describe as "the potent activity of PC SPES against colon cancer" found in both in vitro tests and in mice.

"PC SPES resulted in a marked suppression of cell proliferation in all colon cancer cells studied" in the laboratory, the researchers reported. And when tested in mice, those given PC SPES had a 58 percent descrease in the number of colorectal tumors, according to the researchers.

"This suggests that the components of this herbal mixture, either independently or in combination, acted in colon cancer, resulting in a drastic effect on tumor initiation and tumor progression," the researchers concluded.

While PC SPES is not likely to make an early return to the market, the findings suggest that debates over its value in fighting cancer -- as well as efforts to identify which components of the product account for its apparent cancer-fighting properties -- are likely to continue.

Other Sources: Cancer Research