Compounds in mate tea induce death in colon cancer cells

Could preventing colon cancer be as simple as developing a taste for yerba mate tea? In a recent University of Illinois study, scientists showed that human colon cancer cells die when they are exposed to the approximate number of bioactive compounds present in one cup of this brew, which has long been consumed in South America for its medicinal properties.

"The caffeine derivatives in mate tea not only induced death in human colon cancer cells, they also reduced important markers of inflammation," said Elvira de Mejia, a U of I associate professor of food chemistry and food toxicology.

That's important because inflammation can trigger the steps of cancer progression, she said.

In the in vitro study, de Mejia and former graduate student Sirima Puangpraphant isolated, purified, and then treated human colon cancer cells with caffeoylquinic acid (CQA) derivatives from mate tea. As the scientists increased the CQA concentration, cancer cells died as a result of apoptosis.

"Put simply, the cancer cell self-destructs because its DNA has been damaged," she said.

The ability to induce apoptosis, or cell death, is a promising tactic for therapeutic interventions in all types of cancer, she said.

de Mejia said they were able to identify the mechanism that led to cell death. Certain CQA derivatives dramatically decreased several markers of inflammation, including NF-kappa-B, which regulates many genes that affect the process through the production of important enzymes. Ultimately cancer cells died with the induction of two specific enzymes, caspase-3 and caspase-8, de Mejia said.

Get screened for colon cancer People with an average risk of colon cancer can consider screening beginning at age 50. But people with an increased risk, such as those with a family history of colon cancer, should consider screening sooner. African-Americans and American Indians may begin colon cancer screening at age 45.

Several screening options exist - each with its own benefits and drawbacks. Talk about your options with your doctor, and together you can decide which tests are appropriate for you. Options may include:

Annual fecal occult blood testing
Flexible sigmoidoscopy every five years
Colonoscopy every 10 years
Virtual colonoscopy (CT colonography) every five years
Stool DNA testing - though this is a new screening approach and it's not clear how often it should be repeated

More frequent or earlier screening may be recommended if you're at increased risk of colon cancer. Discuss the benefits and risks of each screening option with your doctor. You may decide one or more tests are appropriate for you.

"If we can reduce the activity of NF-kappa-B, the important marker that links inflammation and cancer, we'll be better able to control the transformation of normal cells to cancer cells," she added.