Brown Algae as a Protector Against Skin Cancer

Ultraviolet B (UVB) radiation from the sun is believed to cause up to 90% of skin cancers that aren't melanomas. These kinds of cancer may not be malignant, but treatment can still be complex, possibly including radiation or chemotherapy. Now, though, researchers have discovered that substances in brown algae may be able to prevent or at least limit the development of these kinds of cancer.

The substances are called brown algae polyphenols (BAPs). In the latest research, performed at Ohio State University Comprehensive Cancer Center, hairless mice that are prone to develop UVB-related skin cancers were divided into several groups. Some were treated with BAPs and others weren't. Then all the mice were exposed to UVB radiation for a period of 24 weeks - almost six months.

After the radiation period the mice were checked for skin tumors, and the tumors were counted and measured. It was discovered that the mice treated with brown algae polyphenols had about half the number of tumors that the non-treated mice had. The tumors in the treated mice were also much smaller.

The researchers also wanted to measure the level of the skin's inflammation. They did this by checking the levels of cyclooxygenase-2 (COX-2), an enzyme, and prostaglandin E2, a substance similar to a hormone. The mice who'd received the brown algae polyphenols had much lower levels of both COX-2 and prostaglandin E2, meaning their skin was less inflamed than that of the non-treated mice.

What is it about brown algae polyphenols that may have produced this extra protection? Scientists do say that BAPs are antioxidants. Antioxidants help prevent cells from trading oxygen molecules, which can lead to cell mutations and overgrowth. And brown algae in general contains other substances known to be healthy to humans, including carotenes (which are also antioxidants) and chlorophylls.

The researchers were also pleased to learn that it didn't take much to produce this protection. The BAPs were effective at fairly low doses.

Where will they go from here? Well, when it comes to research, there can be a quite a distance between lab and human testing. But brown algae polyphenols have already proven their flexibility - they work both internally (through ingestion) and externally (on the skin). This flexibility may help them "translate" to human use more easily. The success of this research with mice may eventually result in the development of products that can help keep humans from developing UVB-related skin cancers.