These bacteria on the skin protect against skin cancer

Bacteria provide natural protection against skin cancer?

Generally, most people try to avoid contact with germs and bacteria. However, there are also bacteria that have a positive effect on health. Researchers have now found that bacteria found on the skin appear to protect against skin cancer.

Researchers at the University of California, San Diego found that skin-borne bacteria can help protect against skin cancer. The experts published the results of their study in the English language journal "Science Advances".

Especially in skin cancer, early detection of the disease is very important. Only then can an effective treatment be initiated. Physicians now found that naturally occurring on the skin bacteria seem to protect against skin cancer. (Image: M.Dörr & M.Frommherz / fotolia.com)

Some bacteria are healthy for humans

Not all bacteria harm humans. There are several examples such as probiotics and healthy intestinal bacteria. Now a new group of bacteria has been identified, which seems to have positive effects. These are the common human skin bacteria of the genus Staphylococcus epidermidis. These produce a substance that can prevent the growth of tumors.

Staphylococcal bacteria protect mice from cancer

The researchers studied the antimicrobial capabilities of staphylococcal bacteria. This type of bacteria normally lives on human skin. Their investigation revealed something unexpected. When mice were treated with these bacteria, this resulted in a remarkable resistance to skin cancer in experimental animals, the authors explain.

The compound 6-N-hydroxyaminopurine gives the protective effect

In further investigations, the responsible for the natural protection compound could be identified, which was produced by the bacteria. These were 6-N-hydroxyaminopurine (HAL-6). Because of the structure of the compound (it resembled the building blocks of DNA), the physicians wondered if it could interfere with DNA synthesis. In additional experiments, the researchers found that the secreted compound actually affects the machinery of DNA synthesis.

HAL-6 prevents growth of cancer cells

HAL-6 blocks the enzyme that builds DNA chains and prevents the growth of these chains, the researchers say. This may sound like a negative ability at first, but the connection did not affect normal healthy skin cells. Instead, however, HAL-6 acted on cancer cells and prevented out-of-control growth.

Effect of HAL-6 on mice

When the bacterial flora in the mice did not secrete HAL-6, the animals became relatively quickly exposed to skin cancer after exposure to high UV doses. In mice with an intact bacterial flora, the compound was produced, causing them to be protected from cancer after irradiation, the researchers explain. The researchers were also able to show that HAL-6 not only has a preventive effect, but also inhibits the growth of tumor cells that have already formed. When mice challenged with cancer received HAL-6 every 48 hours, this resulted in the animals' tumors becoming 50 percent smaller within two weeks compared to the tumors of control mice.

HAL-6 has great potential

The results highlight the potential of the microbiome to influence human disease. People seem to have developed a mutually beneficial relationship with this bacterium over time, says study author Richard Gallo of the University of California, San Diego. We may have evolved to provide the organisms with a safe haven because the bacteria are also beneficial to humans, the expert suggests.

The compound HAL-6 still functioned when isolated from the bacteria - both when injected and when applied topically. This shows their potential for future treatments, which need not only affect skin cancer. The researchers also found that HAL-6 is also effective in reducing growth rates of lymphoma cells, so this natural defense may possibly be used for a much broader application.

Further research is needed

Of course, further research will be needed to examine exactly how Staphylococcus epidermidis produces the compound and whether it has a toxic content. Only about 20 percent of the population have these bacteria on their skin, so it must be ensured that they are safe for all humans, the researchers emphasize. The results of the study also recall that only a very small percentage of the organisms around us are actually harmful and many of us benefit instead. (As)