Research shows that estrogen receptor β has a protective effect on colon cancer and may inhibit proliferation of colon cancer cells. Estrogen receptor β is the main estrogen receptor expressed at a high level by normal human colon mucosa. In a cancerous colon, however, expression of estrogen receptor β decreases and is associated with progression of colorectal cancer.
Interest in phenols present in extra virgin olive oil as possible anti-carcinogenic agents for colon cancer stems from the fact that most phenols have a chemical structure similar to 17 β-estradiol (main form of estrogen in humans) and may be protective against colon cancer by acting as selective estrogen receptor modulators.
In a recent study carried out in the University of Florence and published in the Journal Nutrition and Cancer, researchers evaluated the effects of phenolic extracts from two different Italian varieties of extra virgin olive oil on human colon cancer cell lines in vitro. They reported that the total polyphenol content of the EVOOs, supplied by companies from Tuscany and Liguria, was 12.69 and 8.43 milligrams per milliliter, respectively. Hydroxytyrosol, secoiridoids and lignans were the main phenolic extracts identified in these EVOOs.
The phenol extracts were tested on human colon cancer cell lines that were designed to overexpress estrogen receptor β. The authors reported that the EVOO extracts interacted with signals dependent on estrogen for growth of colorectal cancerous cells, thus providing an anti-proliferative effect on them. EVOO extracts also down regulated the expression of several genes, including BAG-1 that resulted in inhibition of cellular growth.
The researchers plan on conducting more studies to investigate the role of EVOO extracts in stopping colorectal cancer growth through the estrogen receptor β metabolic pathway.
Colorectal cancer is the third most common cancer and the second leading cause of cancer-related deaths in the United States, according to the Center for Disease Control and Prevention.
These latest findings add to the health benefits of consuming a Mediterranean diet, which provides many cancer-protective components because it is a diet rich in fruits, vegetables, olive oil, seafood, whole grains, and wine.
Sources: Olive Oil Times