• 3/29/2003
  • Houston, Texas
  • Reuters News Service / SOURCE: Blood 2003;101:1053-1062.

An ingredient in the curry spice turmeric may help suppress and destroy a blood cancer, early lab research shows–suggesting yet another health benefit from this long-heralded substance. Turmeric is a common ingredient in Indian food and yellow mustard. Its active ingredient is curcumin, which gives turmeric its yellow color. Adding curcumin to human cells with the blood cancer multiple myeloma, Dr. Bharat B. Aggarwal of the University of Texas MD Anderson Cancer Center in Houston and his colleagues found, stopped the cells from replicating. And the cells that were left died.

Although the study did not test the benefits of curcumin in patients, previous research has shown the substance may fight other types of cancers, Aggarwal told Reuters Health. Studies have also shown that curcumin, even in large quantities, does not produce any known side effects in humans, the researcher noted. Based on this evidence, Aggarwal recommended that people with cancer should try to eat more curcumin, if possible. “Whichever way you can take it, as much as possible,” he said. Aggarwal added, however, that further research is needed to determine how much curcumin people need to get the most benefits.

Previous laboratory research has shown that curcumin may have antioxidant and anti-inflammatory properties, as well as treat and prevent cancer. Patients with multiple myeloma are in particular need of new treatments, Aggarwal and his colleagues point out in their report in the journal Blood. Once diagnosed with this blood cancer, patients typically live between two and three years.

During the current study, the researchers added curcumin to a sample of human cells with multiple myeloma, and observed how the substance influenced the progression of the cancer. In an interview, Aggarwal explained that curcumin appears to block the activity of a “light switch” called nuclear factor kappa-B (NF-kappaB). When turned on, he said, NF-kappaB appears to then turn on many genes linked to cancer. Examining the multiple myeloma cells before adding the curcumin, the authors found that virtually all contained activated forms of NF-kappaB.

After adding curcumin, however, NF-kappaB activity was inhibited, the multiple myeloma cells no longer replicated and the remaining cells died, Aggarwal said. Aggarwal explained that it is somewhat difficult to study the effects of curcumin in a large number of patients because these experiments cost a lot of money. Funding for similar research is often provided by a company that stands to benefit if the tested treatment works; however, in the case of curcumin, a natural compound, no company can reap the benefits if turmeric shows itself to be an effective anti-cancer drug, he said. However, Aggarwal said that he hopes the new findings and previous research suggesting curcumin’s benefits inspire other researchers to continue investigating its properties.

The following is the actual science behind this new article for those interested. Taken from the publication Cancer Reasearch. (Cancer Res 2002 Oct 1;62(19):5451-6)

Curcumin activates the aryl hydrocarbon receptor yet significantly inhibits (-)-benzo(a)pyrene-7R-trans-7,8-dihydrodiol bioactivation in oral squamous cell carcinoma cells and oral mucosa.

Authors: Rinaldi AL, Morse MA, Fields HW, Rothas DA, Pei P, Rodrigo KA, Renner RJ, Mallery SR. College of Dentistry, Departments of Orthodontics and Oral Maxillofacial Surgery and Pathology, Ohio State University, Columbus, Ohio 43218, USA.

The development of oral squamous cell carcinoma (SCC) shows a positive correlation with the carcinogen exposure that occurs during tobacco and alcohol use. The purpose of this study was to investigate whether the naturally occurring chemopreventive agent, curcumin, modulates expression and function of carcinogen- metabolizing enzymes in human keratinocytes isolated from oral SCC tumors. Dose-response studies demonstrated that curcumin concentrations of >or=25 micro M were cytotoxic for oral SCC cells. Curcumin increased both expression (reverse transcription-PCR analyses) and function (high-performance liquid chromatography determination of ethoxyresorufin metabolism) of cytochrome P-450 (CYP) 1A1 and/or CYP1B1. The aryl hydrocarbon receptor (AhR), which up-regulates a battery of genes associated with carcinogen metabolism, is activated by polycyclic aromatic hydrocarbons such as the tobacco-associated carcinogen benzo(a)pyrene. Electromobility shift assays demonstrated that similar to the established AhR ligand 2,3,7,8,-tetrachlorodibenzo-p-dioxin, curcumin inclusion resulted in AhR nuclear translocation and formation of the transcriptionally active AhR-aryl hydrocarbon receptor nuclear translocator complex. Cellular capacity to bioactivate the tobacco-associated carcinogen (-)-benzo(a)pyrene-7R-trans-7,8-dihydrodiodiol was determined by evaluating conversion of the carcinogenic metabolite diol epoxide to stable tetrols via high-performance liquid chromatography. Results of our metabolism studies showed that curcumin significantly inhibited CYP1A1-mediated benzo(a)pyrene diol bioactivation in both oral SCC cells and intact oral mucosa. Because CYP1A1 is one of the primary carcinogen-activating enzymes in oral mucosa, the use of curcumin as an oral cavity chemopreventive agent could have significant clinical impact via its ability to inhibit carcinogen bioactivation.