10-24-2008, 10:54 AM
Join Date: Apr 2006
Location: Propecia, CA
Carotenoids vs. Colon Cancer
Lutein and zeaxanthin can benefit colon cancer, say researchers
By Shane Starling
Korean researchers have found alga-extracted carotenoids such as lutein and zeaxanthin can reduce colon cancer growths.
The carotenoids extracted from two popular Asian algae forms – Chlorella ellipsoidea (CEE) and Chlorella vulgaris (CVE) – blocked growth of human colon cancer cells, the scientists found.
Lutein and zeaxanthin, more commonly known for eye health benefits, were not the only xanthophylls present in the algae but it was suggested they were the most bioactive.
They also found the extracts had a more powerful anti-cancer effect when used in combination than in isolation.
CVE was composed almost entirely of lutein and found to be 2.5 less effective at inducing apoptosis than CEE – made up of zeaxanthin along with violaxanthin and antheraxanthin.
“These results indicate that bioactive xanthophylls of C. ellipsoidea might be useful functional ingredients in the prevention of human cancers,” the researchers wrote.
But they noted both extracts were effective in battling colon cancer.
“These semi-purified extracts of CEE and CVE both inhibited the growth of HCT116 (the colon cancer cells) in a dose-dependent manner,” they said.
“Considerable evidence supports the theory that some carotenoids, such as β-carotene and lycopene, may interfere with cancer-related molecular pathways and change the expression of many proteins involved in apoptosis.”