POTENT SPICE WORKS TO BLOCK GROWTH OF MELANOMA IN LAB TEST

[Guest guest]

Contact: Heather Sessions

hrsessions

713-792-0655

University of Texas M. D. Anderson Cancer Center

 

Potent spice works to block growth of melanoma in lab test

HOUSTON - Curcumin, the pungent yellow spice found in both turmeric

and curry powders, blocks a key biological pathway needed for

development of melanoma and other cancers, say researchers from The

University of Texas M. D. Anderson Cancer Center.

The study, to be published in the August 15, 2005 issue of the

journal Cancer, but available on line at 12:01 a.m. (EDT) on Monday,

July 11, demonstrates how curcumin stops laboratory strains of

melanoma from proliferating and pushes the cancer cells to commit

suicide.

 

It does this, researchers say, by shutting down nuclear factor-kappa

B (NF-kB), a powerful protein known to promote an abnormal

inflammatory response that leads to a variety of disorders, including

arthritis and cancer.

 

The study is the latest to suggest that curcumin has potent

anticancer powers, say the researchers.

 

" The antioxidant, anti-inflammatory and anti-carcinogenic properties

of curcumin derived from turmeric are undergoing intense research

here and at other places worldwide, " says one of the study's authors,

Bharat B. Aggarwal, Ph.D., professor of cancer medicine in the

Department of Experimental Therapeutics.

 

At M. D. Anderson, for example, dramatic results from laboratory

studies have led to two ongoing Phase I human clinical trials,

testing the ability of daily capsules of curcumin powder to retard

growth of pancreatic cancer and multiple myeloma. Another Phase I

trial is planned for patients with breast cancer, and given this news

of curcumin's activity in melanoma, animal studies will soon begin,

Aggarwal says.

 

Ground from the root of the Curcuma longa plant, curcumin is a member

of the ginger family. It has long been utilized in India and other

Asian nations for multiple uses: as a food-preservative, a coloring

agent, a folk medicine to cleanse the body, and as a spice to flavor

food (two to five percent of turmeric is curcumin, for example).

 

While researchers had thought curcumin primarily has anti-

inflammatory properties, the growing realization that cancer can

result from inflammation has spurred mounting interest in the spice

as an anti-cancer agent, Aggarwal says. He adds that another fact has

generated further excitement: " The incidence of the top four cancers

in the U.S. - colon, breast, prostate, and lung - is ten times lower

in India, " he says.

 

This work is just the latest by M. D. Anderson researchers to show

how curcumin can inhibit cancer growth. " Curcumin affects virtually

every tumor biomarker that we have tried, " says Aggarwal. " It works

through a variety of mechanisms related to cancer development. We,

and others, previously found that curcumin down regulates EGFR

activity that mediates tumor cell proliferation, and VEGF that is

involved in angiogenesis. Besides inhibiting NF-kB, curcumin was also

found to suppress STAT3 pathway that is also involved in

tumorigenesis. Both these pathways play a central role in cell

survival and proliferation. "

 

He said that an ability to suppress numerous biological routes to

cancer development is important if an agent is to be

effective. " Cells look at everything in a global way, and inhibiting

just one pathway will not be effective, " says Aggarwal.

 

In this study, the researchers treated three different melanoma cell

lines with curcumin and assessed the activity of NF-kB, as well the

protein, known as " IKK " that switches NF-kB " on. " The spice kept both

proteins from being activated, so worked to stop growth of the

melanoma, and it also induced " apoptosis, " or programmed death, in

the cells.

 

Surprisingly, it didn't matter how much curcumin was used, says the

researchers. " The NF-kB machinery is suppressed by both short

exposures to high concentrations of curcumin as well as by longer

exposure to lower concentrations of curcumin, " they say in their

study. Given that other studies have shown curcumin is non-toxic,

these results should be followed by a test of the spice in both

animal models of melanoma and in human trials, they say.

 

 

###

The study was funded by the National Cancer Institute and the

Department of Defense. Co-authors included principle investigator

Razelle Kurzrock, M.D.; first author Doris Siwak, Ph.D. and Shishir

Shishodia.