A specific strain of staph bacteria could help prevent skin cancer, a new study has found.
Researchers at the University of California San Diego exposed mice with tumors to Staphylococcus epidermidis bacteria and found that a molecule produced by the bacteria stopped the tumors from growing.
One in five Americans will be diagnosed with skin cancer by age 70, according to data from the Centers for Disease Control and Prevention.
The findings could lead to a new way to decrease the risk of skin cancer or a less toxic way to treat existing cancer, lead researcher Dr Richard Gallo told Daily Mail Online.
A study by the University of California San Diego found that strains of a type of bacteria called Staphylococcus epidermidis (pictured) prevented the growth of skin cancer tumors
The researchers at UCSD had set out to determine if harmless types of Staphylococcus bacteria could be effective in fighting other bacteria that cause diseases when they stumbled on the skin cancer results.
There are 11 types of Staphylococcus bacteria that can live on the skin or in the nose.
While in most cases the bacteria are harmless, it can can cause infections with symptoms ranging from mild skin irritation to life-threatening blood poisoning.
One of the most dangerous forms of staph infection is methicillin-resistant Staphylococcus aureus (MRSA), which can eat away at a person’s flesh.
‘We were looking for chemicals that could kill bacteria like MRSA, and accidentally discovered an anti-tumor activity,’ Dr Gallo, chair of the Department of Dermatology, said.
The study involved exposing mice that had been given skin cancer to two different types of Staphylococcus epidermidis, one ‘run-of-the-mill’ type and one that had been found to produce a molecule called 6-N-hydroxyaminopurine (6-HAP).
The mice that were coated with the bacteria that produced 6-HAP had many fewer tumors than those who were exposed to regular S. epidermidis.
According to Dr Gallo, 6-HAP prevents tumor growth by inhibiting DNA synthesis.
‘This unique strain of skin bacteria produces a chemical that kills several types of cancer cells but does not appear to be toxic to normal cells,’ said Dr Gallo.
They researchers initially identified 6-HAP when testing the effects of various strains of Staphylococcus on pathogenic bacteria called group A strep, which can cause a range of infections from strep throat to cellulitis to necrotizing fasciitis, a flesh-eating condition.
After confirming that 6-HAP was the key agent in killing off group A strep bacteria, the researchers hypothesized that perhaps the chemical would have an effect on skin cancer because the molecule stopped DNA synthesis.
They then screened more than 10,000 strains of S. epidermidis and found that two produced the molecule.
‘Because each person has many different [staph] strains on their body, we found 6-HAP genes on about 20 percent of the normal population,’ Dr Gallo said.
Further research will need to be conducted into the possibility of using S. epidermidis to prevent or treat skin cancer, but Dr Gallo said it was ‘very likely’ that these findings will be applied down the road.
‘This is very promising because of the safety of using the normal bacteria found on human skin,’ he said.
Dr Gallo helped found a company called MatriSys Bioscience that is trying to develop bacteria as medical treatments for skin conditions based on emerging research on the body’s microbiome.
A microbiome is a collection of microbes that live in and on the human body and are essential for keeping humans healthy.
Dr Gallo said that there have been reports that dysbiosis, an imbalance in a person’s microbiome, may promote cancer.
On the flip side, research has shown that having a substantial population of ‘good’ bacteria can help fight ‘bad’ bacteria that can cause diseases.
The use of fecal transplants in patients with colitis is a common example of how good bacteria can be effective in combating disease.
Dr Gallo’s team has been using knowledge of bacteria to come up with treatments for skin conditions such as eczema and staph infections.