We've spoken here before about the premature extrapolation of in vitro data on curcumin to the misleading human use of the spice-derivative for a whole host of cancers. Unfortunately, curcumin is not absorbed into the bloodstream at concentrations necessary for anticancer effects, even when combined with a black pepper-derived compound called piperine (sold under the brand name, Bioperine). In fact, piperine/Bioperene may present a risk of drug interactions and potentially increase the side effects of some types of chemotherapy if taken unwittingly along with certain drugs.
However, a cancer prevention specialist at the University of California at Irvine is investigating curcumin systematically in a precancerous setting where it has some potential of having benefit. As the featured clinical trial in yesterday's NCI Cancer Bulletin, "Phase II Chemoprevention Study of Curcumin in Current Smokers with Aberrant Crypt Foci" (UCIRVINE-UCI04-2-01), proposes to investigate whether 30 days of curcumin administration reduces the incidence of precursor lesions to colon cancer. (See the protocol summary at http://cancer.gov/clinicaltrials/UCIRVINE-UCI04-2-01.).
This trial is clever in that it takes advantage of the fact that curcumin is poorly absorbed from the gastrointestinal tract. Moreover, it is not aimed at treating colon cancer that has already occurred but rather cellular lesions that are beliefed to precede the development of colon cancer.
From the interview with UC-Irvine's Dr Frank Meyskens:
Microscopic lesions in the lining of the colon called aberrant crypt foci (ACF) are thought to be precursors of colon polyps and, ultimately, malignant tumors. ACF lesions typically display biomarkers that may indicate precancerous development. In this trial, researchers are exploring the ability of a substance called curcumin to affect these biomarkers and possibly stop the progression to cancer...
Doctors are interested in determining whether curcumin supplements taken for 30 days can help reduce the levels of precancerous biomarkers in the ACF of smokers who have eight or more lesions. Smoking is a known risk factor for colon cancer, and studies suggest that as many as 80 percent of smokers have ACF lesions.
"Though it has been used for centuries in traditional medicine, we're very early in the clinical development of curcumin as a chemopreventive agent," Dr. Meyskens said. "This trial is a proof-of-principle study to see if curcumin really can affect the relevant biomarkers in humans. If it does, we can then design a larger cancer prevention trial based on demonstrated biological response rather than on results from epidemiological studies."
Note that what this trial is not doing is testing curcumin against already advanced colon cancer. This will be an interesting trial to follow, again, especially since it seems to take advantage of the fact that curcumin is poorly absorbed from the intestinal tract.
Other investigators and enrollment sites are; Dr. Richard Banya, University of Illinois at Chicago; Dr. D. Kim Turgeon, University of Michigan.
My earlier posts on curcumin:
Curcumin for cancer: part one
Curcumin for cancer: part two
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I found this study most interesting.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&do…
1: Clin Gastroenterol Hepatol. 2006 Aug;4(8):1035-8. Epub 2006 Jun 6. Links
Combination treatment with curcumin and quercetin of adenomas in familial adenomatous polyposis.
Cruz-Correa M,
Shoskes DA,
Sanchez P,
Zhao R,
Hylind LM,
Wexner SD,
Giardiello FM.
Department of Medicine, Cleveland Clinic, Weston, Florida, USA.
BACKGROUND & AIMS: Familialadenomatous polyposis (FAP) is an autosomal-dominant disorder characterized by the development of hundreds of colorectal adenomas and eventual colorectal cancer. Regression of adenomas in this syndrome occurs with the administration of nonsteroidal anti-inflammatory drugs and cyclooxygenase-2 inhibitors, but these compounds can have considerable side effects. We evaluated the efficacy of the combination of diet-derived nonprescription supplements curcumin and quercetin to regress adenomas in patients with FAP. METHODS: Five FAP patients with prior colectomy (4 with retained rectum and 1 with an ileal anal pouch) received curcumin 480 mg and quercetin 20 mg orally 3 times a day. The number and size of polyps were assessed at baseline and after therapy. The Wilcoxon signed-rank test was used to determine differences in the number and size of polyps. Treatment side effects and medication compliance also were evaluated. RESULTS: All 5 patients had a decreased polyp number and size from baseline after a mean of 6 months of treatment with curcumin and quercetin. The mean percent decrease in the number and size of polyps from baseline was 60.4% (P < .05) and 50.9% (P < .05), respectively. Minimal adverse side effects and no laboratory abnormalities were noted. CONCLUSIONS: The combination of curcumin and quercetin appears to reduce the number and size of ileal and rectal adenomas in patients with FAP without appreciable toxicity. Randomized controlled trials are needed to validate these findings.
PMID: 16757216 [PubMed - indexed for MEDLINE]
Hi there,
I very much appreciate the time and effort you devote to sharing your knowledge. I am a cancer survivor (Hodgkin's Lymphoma)
My mother has just been diagnosed with Non Small Cell Lung Cancer stage 4. she is 73 yrs old and is small like a bird (79 lbs).
Do you have any recommendations?
Thanks in advance,
Melissa
Dear Abel,
Perhaps I've missed it, but do you know of any studies measureing bioactivity of curcumin delivered sublingually ? Many who cook with yellow curry powder are impressed by how easily their skin is turned yellow- suggesting to me that curcumin might be a good candidate for sublingual absorption and turmeric powder isn't too bad on it's own (cheap, too!). An individul on a myleoma site is mixing turmeric with chocolate (providing both pH increase and lipid presence) to make sublingual lozanges.
Anyway- just a thought, Warren
I have been reading your writing on curcumin. I have not studies all of it and I realize that it maybe the studies are not complete yet. But just person to person what would your recommendation be on the taking of curcumin and the amount of mg to take on a daily basis to take to prevent colon polys. I recentley had a colon exam and had 4 polyps..
thanking you in advance...
My Best,
Sid Aust