Curcumin and Cancer

Researchers have demonstrated that curcumin inhibited the growth and promoted cell death in three different melanoma cell lines. Curcumin appears to work by suppressing the production of the proteins in the cancer cells that normally protect the cells from cell death. All doses tested decreased cancer cell growth and triggered cell death. Higher doses were more effective, and the higher the dose used, the more cancer cells died. (1)

Curcumin triggered the death of head and neck squamous cell carcinoma in a recent study published in Clinical Cancer Research. This research indicated that the addition of curcumin to cultures of squamous cell carcinoma resulted in a dose-dependent growth inhibition of three cell lines. Researchers also conducted in vivo studies with squamous cell tumors in mice. Topical application of curcumin also inhibited the growth of the cancer cells.

In addition, the researchers conducted in vivo studies by implanting squamous cell tumors in mice. Curcumin was applied as a noninvasive topical paste to the tumors and inhibition of tumor growth was observed. (2)

Additional research at the University of Texas demonstrated that curcumin can stop the spread of multiple myeloma, a cancer of the bone marrow. Curcumin stopped the activation of processes known to lead to the spread of myeloma cells and triggered apoptosis. Apoptosis is a process where cancer cells program themselves to die. (3)

Curcumin can stop the growth of human pancreatic cancer cells, according to a study in the journal Cancer. Researchers found that curcumin inhibited the production of interlukin-8, a protein produced by white blood cells that contributes to tumor growth. (4)

Curcumin as an Antioxidant

Free-radicals can originate from environmental chemicals, tissue injury, infections, and auto-immune processes. Antioxidants protect the body from damage from free-radicals. Water- and fat-soluble extracts of turmeric and its curcumin component exhibit strong antioxidant activity, comparable to vitamins C and E. One study showed curcumin to be eight times more powerful than vitamin E in preventing lipid peroxidation. Taken in group arrangements such as C-complex, curcuminoids are three times as potent in neutralizing free-radical molecules.(5) Several studies have demonstrated curcumin's ability to reduce oxidative stress. (5, 6) It appears that curcumin's role as an antioxidant may be due in part to its ability to down regulate nitric oxide formation. Nitric oxide is a key element in inflammation and may contribute to carcinogenesis.

Curcumin and Turmeric References

(1) Siwak DR, Shishodia S, Aggarwal BB, Kurzrock R. Curcumin-induced antiproliferative and proapoptotic effects in melanoma cells are associated with suppression of IkappaB kinase and nuclear factor kappaB activity and are independent of the B-Raf/mitogen-activated/extracellular signal-regulated protein kinase pathway and the Akt pathway. Cancer. 2005 Jul 11;

(2) LoTempio MM, Veena MS, Steele HL, Ramamurthy B, Ramalingam TS, Cohen AN, Chakrabarti R, Srivatsan ES, Wang MB. Curcumin suppresses growth of head and neck squamous cell carcinoma. Clin Cancer Res. 2005 Oct 1;11(19 Pt 1):6994-7002.

(3) Bharti AC, Donato N, Singh S, Aggarwal BB. Curcumin (diferuloylmethane) down-regulates the constitutive activation of nuclear factor-kappa B and Ikappa Balpha kinase in human multiple myeloma cells, leading to suppression of proliferation and induction of apoptosis. Blood. 2003 Feb 1;101(3):1053-62.

(4) Hidaka H, Ishiko T, Furuhashi T, Kamohara H, Suzuki S, Miyazaki M, Ikeda O, Mita S, Setoguchi T, Ogawa M. Curcumin inhibits interleukin 8 production and enhances interleukin 8 receptor expression on the cell surface: impact on human pancreatic carcinoma cell growth by autocrine regulation. Cancer. 2002 Sep 15;95(6):1206-14.

(5) Toda S, Miyase T, Arich H, et al. Natural antioxidants. Antioxidative compounds isolated from rhizome of Curcuma longa L. Chem Pharmacol Bull 1985;33:1725-1728.

(6) Mortellini R, Foresti R, Bassi R, Green CJ. Curcumin, an antioxidant and anti-inflammatory agent, induces heme oxygenase-1 and protects endothelial cells against oxidative stress. Free Radic Biol Med 2000;28:1303-1312.