Team led by Dr. Zigang Dong shows natural anticancer agent silybin inhibits melanoma

Cancer Prevention Research Journal cover - The Hormel Institute


Researchers at The Hormel Institute have discovered that an anticancer agent in milk thistle significantly inhibits the growth of melanoma, a deadly form of skin cancer afflicting millions of people worldwide.

The cutting-edge discovery by a research team led by The Hormel Institute’s Executive Director Dr. Zigang Dong is featured on the cover of the May 2013 edition of Cancer Prevention Research, a publication by the American Association for Cancer Research that is one of the top cancer research journals.

Silybin, a natural anticancer agent also known as silibinin, is a major bioactive component of the milk thistle plant and has long been used for preventing allergies and liver damage. Several studies have shown silybin’s chemopreventive and/or chemotherapeutic effects against various cancers, including colon, prostate, bladder and lung cancers.

A direct molecular target for silybin, however, had never been identified until researchers at The Hormel Institute revealed silybin’s molecular targets while investigating its effect on melanoma cell growth. Their study found that silybin weakened melanoma growth.

“These research findings are especially significant because, although many common cancers are declining, the incidence of melanoma continues to rise at an estimated rate of 3.1 percent annually,” said Dong, who leads the Institute’s Cellular & Molecular Biology research section.

Skin cancer is the most common form of cancer in the United States. Melanoma – the most aggressive form of skin cancer – accounts for 75 percent of skin cancer deaths.

With this study, researchers used The Hormel Institute’s supercomputer technology to identify a potential inhibitor of a signaling pathway in the body that is an important trigger for melanoma survival, growth and proliferation, Dong said. Thus, developing drugs that target multiple components of this signaling pathway could reduce the incidence and mortality of melanoma skin cancer, he said.

This virtual screening process by the Institute’s supercomputer technology revealed silybin as a potent inhibitor of the signaling pathway. Supercomputing also then was utilized to show how silybin interacts with the pathway.

Silybin and other chemopreventive and/or chemotherapeutic agents with multiple gene targets hold promise in developing effective anticancer drugs, Dong said.

The Hormel Institute, University of Minnesota-Mayo Clinic, is a world-renowned cancer research center focused on discoveries leading to the prevention and control of cancer.

The BioScience Triangle growing the collaborative partnership between the University of Minnesota-Twin Cities, Mayo Clinic-Rochester and The Hormel Institute-Austin is continuing to expand, with plans for a major expansion to begin in 2014 at The Hormel Institute to add more laboratories and better space for its International Center of Research Technology.