Curcumin suppresses the TPA-induced invasion through inhibition of PKCα-dependent MMP-expression in MCF-7 human breast cancer cells.

Curcumin (diferuloylmethane) is a polyphenol derived from the plant turmeric (Curcuma longa), which is commonly used as a spice. Although anti-carcinogenic, anti-oxidant, anti-inflammation, and anti-angiogenic properties have been reported, the effect of curcumin on breast cancer metastasis is unknown. Matrix metalloproteinase-9 (MMP-9) is a major component in cancer cell invasion. In this study, we investigated the inhibitory effect of curcumin on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced MMP-9 expression and cell invasion and the molecular mechanisms involved in MCF-7 cells. Our results showed that curcumin inhibits TPA-induced MMP-9 expression and cell invasion through suppressing NF-κB and AP-1 activation. Also, curcumin strongly repressed the TPA-induced phosphorylation of p38 and JNK and inhibited TPA-induced translocation of PKCα from the cytosol to the membrane, but did not affect the translocation of PKCδ. These results indicate that curcumin-mediated inhibition of TPA-induced MMP-9 expression and cell invasion involves the suppression of the PKCα, MAPK and NF-κB/AP-1 pathway in MCF-7 cells. Curcumin may have potential value in restricting breast cancer metastasis.

Kim JM ，Noh EM ，Kwon KB ，Kim JS ，You YO ，Hwang JK ，Hwang BM ，Kim BS ，Lee SH ，Lee SJ ，Jung SH ，Youn HJ ，Lee YR ... -  《-》

Frondoside A has an anti-invasive effect by inhibiting TPA-induced MMP-9 activation via NF-κB and AP-1 signaling in human breast cancer cells.

Park SY ，Kim YH ，Kim Y ，Lee SJ ... -  《-》

Aromatic-turmerone attenuates invasion and expression of MMP-9 and COX-2 through inhibition of NF-κB activation in TPA-induced breast cancer cells.

Recent evidence suggests that breast cancer is one of the most common forms of malignancy in females, and metastasis from the primary cancer site is the main cause of death. Aromatic (ar)-turmerone is present in Curcuma longa and is a common remedy and food. In the present study, we investigated the inhibitory effects of ar-turmerone on expression and enzymatic activity levels of 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced matrix metalloproteinase (MMP)-9 and cyclooxygenaase-2 (COX-2) in breast cancer cells. Our data indicated that ar-turmerone treatment significantly inhibited enzymatic activity and expression of MMP-9 and COX-2 at non-cytotoxic concentrations. However, the expression of tissue inhibitor of metalloproteinase (TIMP)-1, TIMP-2, MMP-2, and COX-1 did not change upon ar-turmerone treatment. We found that ar-turmerone inhibited the activation of NF-κB, whereas it did not affect AP-1 activation. Moreover, The ChIP assay revealed that in vivo binding activities of NF-κB to the MMP-9 and COX-2 promoter were significantly inhibited by ar-turmerone. Our data showed that ar-turmerone reduced the phosphorylation of PI3K/Akt and ERK1/2 signaling, whereas it did not affect phosphorylation of JNK or p38 MAPK. Thus, transfection of breast cancer cells with PI3K/Akt and ERK1/2 siRNAs significantly decreased TPA-induced MMP-9 and COX-2 expression. These results suggest that ar-turmerone suppressed the TPA-induced up-regulation of MMP-9 and COX-2 expression by blocking NF-κB, PI3K/Akt, and ERK1/2 signaling in human breast cancer cells. Furthermore, ar-turmerone significantly inhibited TPA-induced invasion, migration, and colony formation in human breast cancer cells.

Park SY ，Kim YH ，Kim Y ，Lee SJ ... -  《-》

Suppression of phorbol-12-myristate-13-acetate-induced tumor cell invasion by piperine via the inhibition of PKCα/ERK1/2-dependent matrix metalloproteinase-9 expression.

Piperine is a major component of black pepper, Piper nigrum Linn, used widely in traditional medicine. Several previous studies reported that piperine possesses various beneficial biological activities including antioxidant, anti-tumor and anti-inflammation properties. In the present study, we investigated the inhibitory effects of piperine on tumor invasion and migration and the possible mechanisms involved using human fibrosarcoma HT-1080 cells. We found that piperine suppresses PMA-enhanced matrix metalloproteinase-9 (MMP-9) expression at the protein, mRNA, and transcriptional levels through the suppression of NF-κB and AP-1 activation without changing the level of tissue inhibitor of metalloproteinase (TIMP)-1. Piperine also inhibits PMA-enhanced membrane-type 1 MMP expression without changing the level of tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2. Piperine inhibited PMA-induced NF-κB and c-Jun nuclear translocation, which are upstream of PMA-induced MMP-9 expression and invasion. Furthermore, piperine strongly repressed the PMA-induced phosphorylation of ERK, which are dependent on the PKCα pathway. In conclusion, we demonstrated that the anti-invasive effects of piperine may occur through inhibition of PKCα and ERK phosphorylation and reduction of NF-κB and AP-1 activation, leading to down-regulation of MMP-9 expression. Thus, piperine has potential as a potent anti-cancer drug in therapeutic strategies for fibrosarcoma metastasis.

Hwang YP ，Yun HJ ，Kim HG ，Han EH ，Choi JH ，Chung YC ，Jeong HG ... -  《-》

Suppression of 12-O-tetradecanoylphorbol-13-acetate-induced MCF-7 breast adenocarcinoma cells invasion/migration by α-tomatine through activating PKCα/ERK/NF-κB-dependent MMP-2/MMP-9 expressions.

Shi MD ，Shih YW ，Lee YS ，Cheng YF ，Tsai LY ... -  《-》