In need of a better way to deliver the curcumin, the team collaborated with Dr. Kapil Mehta of M.D. Anderson Cancer Center and found that encapsulating the tumor in a liposome, an artificially prepared vehicle that enclosed the spice component within its membrane, made the treatment injectable. The curcumin was injected into the tail vein of a mouse, where it circulated into the blood stream, slowing down and eventually stopping the cancer growth, a study in 2008 found.
"This was a very positive finding, developing an efficient way to deliver the treatment," Wang said. "Our study also showed that the curcumin was very well tolerated."
In this study, the team wanted to combine the curcumin with the chemotherapeutic drug Cisplatin, which is very toxic at the doses needed to fight head and neck cancers, damaging kidneys, the ears and the bone marrow. They hoped that if they added curcumin to the mix, they might be able to lower the Cisplatin dose and cause less organ damage. Their finding, that the curcumin made the Cisplatin work better, was very promising, Wang said.
"We knew that both the curcumin and the Cisplatin, when given alone, had an effect against head and neck cancers," Wang said. "This finding that curcumin enhances Cisplatin means that, in the future, we may be able to give this chemotherapy in lower doses."
The study noted that "the mechanisms of the two agents through different growth signaling pathways suggest potential for the clinical use of sub-therapeutic doses of Cisplatin in combination with curcumin, which will allow effective suppression of tumor growth while minimizing the toxic side effects."
The study found that curcumin suppressed head and neck cancer growth by regulating cell cycling, Srivatsan said. It binds to an enzyme and prevents the enzyme IKK, an inhibitor of kappa B kinase, from activating a transcription factor called nuclear factor kappa B (NFκB), which promotes cancer growth.
|Contact: Kim Irwin|
University of California -- Los Angeles