This study investigated the mechanisms by which curcumin, a compound found in the spice turmeric, inhibits the growth of MDA-MB-231 and BT-483 breast cancer cells. MDA-MB-231 cells are estrogen receptor negative, progesterone receptor negative and HER-2 negative (i.e., triple negative). The BT-483 cell line was derived from an invasive ductal breast cancer tumor. The study examined curcumin's effect on cell cycle regulation and proliferation. Curcumin was found to inhibit proliferation of both cell lines in a time- and dose-dependent manner. The authors conclude that curcumin reduces proliferation and invasion by down-regulating NFκB inducing genes.

Implications for breast cancer treatment

This study confirms the findings of numerous other studies that have reported that curcumin has anticancer effects against various types of breast cancer cells, including estrogen receptor-positive and progesterone receptor-positive (ER+/PR+), triple negative, and HER2 overexpressing cell lines. The study opens new ground in explaining part of curcumin's mechanism of action.

Adding curcumin to chemotherapy regimes that include Taxol (paclitaxel) or Adriamycin (doxorubicin) has been shown to enhance their cytotoxicity. Curcumin also has been shown to be an iron chelator, which may be helpful in reducing iron for some women, but could negatively impact women with marginal stores of iron or those undergoing chemotherapy. Curcumin has been found in mouse models to effectively protect skin from radiation damage, while at the same time sensitizing breast cancer cells to radiation and making them more susceptible to its effects. Therefore, it appears that adding turmeric to the diet during radiation treatment could be beneficial. While the in vitro and in vivo evidence of curcumin's anti-cancer activities is remarkable, there have been no population studies that specifically address the association between turmeric consumption and the risk of breast cancer.