Pomegranate juice, total pomegranate ellagitannins, and punicalagin suppress inflammatory cell signaling in colon cancer cells.
Phytochemicals from fruits such as the pomegranate (Punica granatum L) may inhibit cancer cell proliferation and apoptosis through the modulation of cellular transcription factors and signaling proteins. In previous studies, pomegranate juice (PJ) and its ellagitannins inhibited proliferation and induced apoptosis in HT-29 colon cancer cells. The present study examined the effects of PJ on inflammatory cell signaling proteins in the HT-29 human colon cancer cell line. At a concentration of 50 mg/L PJ significantly suppressed TNFalpha-induced COX-2 protein expression by 79% (SE = 0.042), total pomegranate tannin extract (TPT) 55% (SE = 0.049), and punicalagin 48% (SE = 0.022). Additionally, PJ reduced phosphorylation of the p65 subunit and binding to the NFkappaB response element 6.4-fold. TPT suppressed NFkappaB binding 10-fold, punicalagin 3.6-fold, whereas ellagic acid (EA) (another pomegranate polyphenol) was ineffective. PJ also abolished TNFalpha-induced AKT activation, needed for NFkappaB activity. Therefore, the polyphenolic phytochemicals in the pomegranate can play an important role in the modulation of inflammatory cell signaling in colon cancer cells.
Adams
Lynn S
LS
Center for Human Nutrition, David Geffen School of Medicine, University of California, Los Angeles, California 90095, USA. ladams@mednet.ucla.edu
Seeram
Navindra P
NP
Aggarwal
Bharat B
BB
Takada
Yasunari
Y
Sand
Daniel
D
Heber
David
D
D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D000970:Antineoplastic Agents / Q000494:pharmacology*; D001628:Beverages / Q000032:analysis*; D051546:Cyclooxygenase 2 / Q000378:metabolism; D005638:Fruit / Q000737:chemistry*; D019073:HT29 Cells; D006801:Humans; D047348:Hydrolyzable Tannins / Q000494:pharmacology*; D007249:Inflammation; D029561:Lythraceae / Q000737:chemistry*; D011494:Protein Kinases / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D000893:Anti-Inflammatory Agents; D000970:Antineoplastic Agents; D047348:Hydrolyzable Tannins; D014409:Tumor Necrosis Factor-alpha; C115642:punicalagin; D051546:Cyclooxygenase 2; D011494:Protein Kinases