IP6 May Stop Growth 
of Liver Cancer Cells

In a study of human liver cancer cells treated with inositol hexaphosphate (IP6) and transplanted into mice, Abulkalam M. Shamsuddin, MD, PhD, professor of pathology at the University of Maryland, and colleagues found that IP6 slowed or stopped the growth of liver cancer cells and shrank existing tumors three- to four-fold. The Maryland researchers report on their findings at the American Association for Cancer Research annual meeting in New Orleans on Monday, March 30, 2000.

"IP6 does not kill cancer cells; it tames them and makes them behave like normal cells," says Shamsuddin. His research has focused on the cancer-fighting properties of the sugar-based compound for more than a decade.

Inositol hexaphosphate is a sugar molecule attached to six phosphate molecules. It is found throughout nature, in wheat and rice bran, legumes such as soybeans, and virtually every kind of mammalian cell. It plays an important role in regulating vital cellular functions, including cell proliferation and differentiation. IP6 decreases proliferation of cancer cells and causes them to differentiate, often reverting to the size, shape and structure of normal cells, Shamsuddin reports. "IP6 has striking anticancer action, both in vitro (in a test tube) and in vivo (in live animals)," he says. In the human liver cancer cell study, Shamsuddin's team treated human hepatocellular carcinoma cells with varying doses of pure IP6. The result was partial to complete inhibition of cell growth and proliferation, depending on the dose. Treated cells transplanted into mice produced no tumors over the 41 days of the experiment, while 71 percent of mice receiving untreated cancer cells developed tumors. Mice that developed tumors from the human cancer-cell line were injected with IP6 for 12 consecutive days. After the last treatment, their tumors weighed three- to four-fold less than they had before the injections, Shamsuddin reports.

IP6 has moved in and out of medical favor ever since its discovery. Its antioxidant properties sparked excitement, followed by concern that IP6 binds tightly with important minerals such as calcium, magnesium, copper, iron and zinc, preventing the body from absorbing them properly. Recent studies have shown that concern to be unfounded, says Shamsuddin.

It is true that IP6, when consumed, combines with various proteins and other large molecules to form insoluble compounds which are not readily absorbed or metabolized, the researcher notes. For that reason, adding IP6 to the diet would be less effective than giving it in a pure form, dissolved in water and either drunk or injected, the researcher says.

"Although IP6 is the substance responsible for cereal's anticancer effects, intake of pure IP6 may be a more practical approach than gorging on enormous quantities of dietary fiber to prevent cancer," he remarks.

Shamsuddin also has tested IP6 on colon, lung, breast and prostate cancer cells, on leukemias, fibrosarcomas and muscle cell cancers in children.

"IP6 has a potential for use as a novel preventive measure and treatment for a variety of cancers," Shamsuddin suggests. It also holds promise for prevention and treatment of cardiovascular disease, kidney stones and possibly even immune-system disorders like AIDS, he says.

Shamsuddin's research was supported in part by the American Institute for Cancer Research.