Potential anticancer properties and mechanisms of action of curcumin.

Curcumin, a yellow substance belonging to the polyphenols superfamily, is the active component of turmeric, a common Indian spice, which is derived from the dried rhizome of the Curcuma longa plant. Numerous studies have demonstrated that curcumin possesses anti-oxidant, anti- inflammatory and anticancerous properties. The purpose of this review is to focus on the anti-tumor effects of curcumin. Curcumin inhibits the STAT3 and NF-ĸB signaling pathways, which play key-roles in cancer development and progression. Also, inhibition of Sp-1 and its housekeeping gene expressions may serve as an important hypothesis to prevent cancer formation, migration, and invasion. Recent data have suggested that curcumin may act by suppressing the Sp-1 activation and its downstream genes, including ADEM10, calmodulin, EPHB2, HDAC4, and SEPP1 in a concentration- dependent manner in colorectal cancer cell lines; these results are consistent with other studies, which have reported that curcumin could suppress the Sp-1 activity in bladder cancer and could decrease DNA binding activity of Sp-1 in non-small cell lung carcinoma cells. Recent data advocate that ER stress and autophagy may as well play a role in the apoptosis process, which is induced by the curcumin analogue B19 in an epithelial ovarian tumor cell line and that autophagy inhibition could increase curcumin analogue-induced apoptosis by inducing severe ER stress. The ability of curcumin to induce apoptosis in tumor cells and its anti-angiogenic potential will be discussed in this review. Curcumin, a yellow substance belonging to the polyphenols superfamily, is the active component of turmeric, a common Indian spice, which is derived from the dried rhizome of the Curcuma longa plant (1-2). Turmeric contains three principal components, curcumin, demethoxycurcumin and bisdemetho- xycurcumin, of which curcumin is the most abundant and potent (3-6). Curcumin comprises approximately 2%-5% of turmeric (7). Numerous studies have demonstrated that curcumin possesses anti-oxidant, anti-inflammatory and anticancer properties (8-18). Its ability to induce apoptosis in tumor cells and anti-angiogenic potential will be discussed in this review. Curcumin's Mechanisms of Action: The Role of STAT3 and NF-ĸB