Two studies from the University of Colorado Cancer Center show that a particular herbal extract can kill cancerous skin cells mutated by exposure to ultraviolet light from the sun and protect against cancer and photoaging.
The extract is silibinin derived from milk thistle.
“When you have a cell affected by UV radiation, you either want to repair it or kill it so that it cannot go on to cause cancer. We show that silibinin does both,” says Rajesh Agarwal, Ph.D., co-program leader of Cancer Prevention and Control at the Cancer Center.
“It has been 20 years of work with this compound, silibinin,” Agarwal says. “We first noticed its effectiveness in treating both skin and solid cancers, and we now have a much more complete picture of the mechanisms that allow this compound to work.
“When you take human skin cells — keratinocytes — and treat them with silibinin, nothing happens. It’s not toxic. But when you damage these cells with UVA radiation, treatment with silibinin kills the cells,” Agarwal says. This beneficial process kills off and removes mutated cells that can cause skin cancer and photoaging.