Please consider registering
guest

Log In Register

Register | Lost password?
Advanced Search

— Forum Scope —

  

— Match —

   

— Forum Options —

   

Minimum search word length is 4 characters - maximum search word length is 84 characters

Topic RSS
new study on cacao and cancer
April 19, 2005
5:11 pm
kevin
Member
Forum Posts: 11
Member Since:
March 9, 2005
Offline

Hi.
This was just published:
Pentameric procyanidin from Theobroma cacao selectively inhibits growth of human breast cancer cells.

Ramljak D, Romanczyk LJ, Metheny-Barlow LJ, Thompson N, Knezevic V, Galperin M, Ramesh A, Dickson RB.

Department of Oncology, The Research Building, Room W417, Lombardi Comprehensive Cancer Center, Georgetown University Medical Center, 3970 Reservoir Road, NW, Washington, DC 20057. dicksonr@georgetown.edu.

A naturally occurring, cocoa-derived pentameric procyanidin (pentamer) was previously shown to cause G(0)/G(1) cell cycle arrest in human breast cancer cells by an unknown molecular mechanism. Here, we show that pentamer selectively inhibits the proliferation of human breast cancer cells (MDA MB-231, MDA MB-436, MDA MB-468, SKBR-3, and MCF-7) and benzo(a)pyrene-immortalized 184A1N4 and 184B5 cells. In contrast, normal human mammary epithelial cells in primary culture and spontaneously immortalized MCF-10A cells were significantly resistant. We evaluated whether this differential response to pentamer may involve depolarization of the mitochondrial membrane. Pentamer caused significant depolarization of mitochondrial membrane in MDA MB231 cells but not the more normal MCF-10A cells, whereas other normal and tumor cell lines tested gave variable results. Further investigations, using a proteomics approach with pentamer-treated MDA MB-231, revealed a specific dephosphorylation, without changes in protein expression, of several G(1)-modulatory proteins: Cdc2 (at Tyr(15)), forkhead transcription factor (at Ser(256), the Akt phosphorylation site) and p53 (Ser(392)). Dephosphorylation of p53 (at Ser(392)) by pentamer was confirmed in MDA MB-468 cells. However, both expression and phosphorylation of retinoblastoma protein were decreased after pentamer treatment. Our results show that breast cancer cells are selectively susceptible to the cytotoxic effects of pentameric procyanidin, and suggest that inhibition of cellular proliferation by this compound is associated with the site-specific dephosphorylation or down-regulation of several cell cycle regulatory proteins.

April 19, 2005
7:03 pm
ellie
london, United Kingdom
Member
Forum Posts: 308
Member Since:
March 17, 2005
Offline

Great piece of news! Do you think it works in the body as well, not just in primary culture? Chocolate should come with a pink ribbon around it...

new study on cacao and cancer | General Discussions | Forum