The researchers found that the chemical, called 6-N-hydroxyaminopurine (6-HAP), hindered the production of DNA, with work in cell cultures revealing that 6-HAP prevents several types of tumour cells from growing and multiplying
Staphylococcus epidermidis is a
Gram-positive bacterium, and one of over 40 species belonging to the genus
Staphylococcus. It is part of the normal
human flora, typically the skin flora, and less commonly the mucosal flora
It is an facultative anaerobic
bacteria. Although S. epidermidis is not usually pathogenic, patients with
compromised immune systems are at risk of developing infection
That type of bacteria commonly
found on human skin produces a substance that help to protect against skin
cancer, researchers have revealed.
The scientists say the surprise
discovery regarding a strain of Staphylococcus epidermidis highlights
the importance of the community microbes found on and in the body in preventing
disease.
While it is not clear whether the
absence of this strain could increase the risk of skin cancer in individuals,
the team say that it is possible the findings might one day lead to preventive
treatments for patients.
“The presence of this strain may provide natural
protection, or it might be used therapeutically to inhibit the growth of
various forms of cancer,” said Prof Richard Gallo, a co-author of the research
from the University of California, San Diego.
The finding was somewhat
serendipitous. With previous research showing that chemicals produced by Staphylococcus species
commonly found on healthy human skin can kill off certain harmful bacteria, the
team looked at numerous strains to explore their antimicrobial powers.
Writing in the journal Science
Advances, Gallo and colleagues describe how among their results, they
discovered a strain of Staphylococcus epidermidis which
produced a substance that killed off a type harmful bacteria responsible for
infections such as strep throat. While it was not the only strain to do so, the
chemical these microbes produced was unusual, boasting a structure similar to
one of the key components of DNA, called adenine.
“The strain was originally detected
in a screen for antimicrobial activity, but when we identified the nature of
the chemical produced by this strain we proceeded with experiments to determine
if it might have activity against tumours,” said Gallo.
The researchers found that the
chemical, called 6-N-hydroxyaminopurine (6-HAP), hindered the production of
DNA, with work in cell cultures revealing that 6-HAP prevents several types of
tumour cells from growing and multiplying.
By injecting mice with this
substance, the team found that 6-HAP is not toxic. However, when melanoma cells
were introduced to mice, animals which had received 6-HAP intravenously ended
up with tumours that were more than 60% smaller than those that had not
received the substance.
Bacteria 6-HAP is not currently
found in any Food and Drug Administration approved drug, according to the FDA’s
database.