Milk thistle extract stops lung cancer in mice

November 15, 2011, University of Colorado Denver

Tissue with wound-like conditions allows tumors to grow and spread. In mouse lung cancer cells, treatment with silibinin, a major component of milk thistle, removed the molecular billboards that signal these wound-like conditions and so stopped the spread of these lung cancers, according to a recent study published in the journal Molecular Carcinogenesis.

Though the natural extract has been used for more than 2,000 years, mostly to treat disorders of the liver and , this is one of the first carefully controlled and reported studies to find benefit.

Here is how it works:

Basically, in a cell there can be a chain of signals, one leading to the next, to the next, and eventually to an end product. And so if you would like to eliminate an end product, you may look to break a link in the signaling chain that leads to it. The end products and iNOS are enzymes involved with the to perceived wounds – both can aid growth. Far upstream in the signaling chain that leads to these unwanted enzymes are STAT1 and STAT3. These transcription factors allow the blueprint of DNA to bind with proteins that continue the signal cascade, eventually leading to the production of harmful COX2 and iNOS.

Stop STAT1 and STAT3 and you break the chain that leads to COX2 and iNOS – and the growth of lung tumors along with them.

"This relatively nontoxic substance – a derivative of milk thistle, called silibinin – was able to inhibit the upstream signals that lead to the expression of COX2 and iNOS," says Alpna Tyagi, PhD, investigator at the University of Colorado Cancer Center and member of the Agarwal Lab at the Skaggs School of Pharmacy and Pharmaceutical Sciences.

In addition, Tyagi and collaborators compared the effects of silibinin to drugs currently in clinical trials for lung cancer. Would drugs that target other signaling pathways – other linked chains – similarly cut into the production of COX2 and iNOS?

It turned out that inhibiting the chains of JAK1/2 and MEK in combination and also inhibiting the signaling pathways of EGFR and NF-kB in combination blocked the ability of STAT1 and STAT3 to trap the energy they needed to eventually signal COX2 and iNOS production.

Compared to these multi-million dollar drugs, naturally-occurring silibinin blocked not only the expression of COX2 and iNOS, but also the migration of existing .

"What we showed is that STAT1 and STAT3 may be promising therapeutic targets in the treatment of , no matter how you target them," Tyagi says. "And also that naturally-derived products like silibinin may be as effective as today's best treatments."

Explore further: Reversing smoke-induced damage and disease in the lung

Related Stories

Reversing smoke-induced damage and disease in the lung

October 13, 2011
By studying mice exposed to tobacco smoke for a period of months, researchers have new insight into how emphysema and chronic obstructive pulmonary disease (COPD) develops. In the October 14th issue of Cell they also report ...

New study finds compounds show promise in blocking STAT3 signaling as treatment for osteosarcoma

April 11, 2011
A study appearing in the journal Investigational New Drugs and conducted by researchers at Nationwide Children's Hospital, discovered that two new small molecule inhibitors are showing promise in blocking STAT3, a protein ...

New drug target for kidney disease discovered

April 26, 2011
Two discoveries at UC Santa Barbara point to potential new drug therapies for patients with kidney disease. The findings are published in this week's issue of the Proceedings of the National Academy of Sciences.

TGen presents lung cancer studies at Amsterdam conference

July 7, 2011
The Translational Genomics Research Institute (TGen) is presenting two key studies, including one today, at the 14th World Conference on Lung Cancer, July 3-7 in Amsterdam.

Recommended for you

Boosting cancer therapy with cross-dressed immune cells

January 22, 2018
Researchers at EPFL have created artificial molecules that can help the immune system to recognize and attack cancer tumors. The study is published in Nature Methods.

Workouts may boost life span after breast cancer

January 22, 2018
(HealthDay)—Longer survival after breast cancer may be as simple as staying fit, new research shows.

Cancer patients who tell their life story find more peace, less depression

January 22, 2018
Fifteen years ago, University of Wisconsin–Madison researcher Meg Wise began interviewing cancer patients nearing the end of life about how they were living with their diagnosis. She was surprised to find that many asked ...

Single blood test screens for eight cancer types

January 18, 2018
Johns Hopkins Kimmel Cancer Center researchers developed a single blood test that screens for eight common cancer types and helps identify the location of the cancer.

Researchers find a way to 'starve' cancer

January 18, 2018
Researchers at Vanderbilt University Medical Center (VUMC) have demonstrated for the first time that it is possible to starve a tumor and stop its growth with a newly discovered small compound that blocks uptake of the vital ...

How cancer metastasis happens: Researchers reveal a key mechanism

January 18, 2018
Cancer metastasis, the migration of cells from a primary tumor to form distant tumors in the body, can be triggered by a chronic leakage of DNA within tumor cells, according to a team led by Weill Cornell Medicine and Memorial ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.