As discussed in class, the body comes into contact with
bacteria on the surface of our skin or throughout our digestive tract.
Therefore, the microbiomes of these locations contain a plethora of ‘good’ and ‘bad’
bacteria that take up surface area. Residing on the skin, the
Staphylococcal species of bacteria are the most abundant of species. A recent
study came out last month (in February) identifying strains from this
species called Staphylococcus epidermidis
to have especially beneficial properties. So what is so special about this
bacteria? They have the potential to be used to inhibit cancerous cell growths
on the skin and also provide an exciting lead for the prevention of skin
cancer.
The bacteria produce a chemical compound called
6-N-hydroxyaminopurine (6-HAP) that “inhibits DNA polymerase activity." This
molecule has a very similar structure to one of the building blocks of DNA
which is why 6-HAP blocks the enzyme that builds DNA chains.
Richard Gallo, a physician scientist at the University of
California San Diego, and his colleagues used mice to investigate the effects of
6-HAP on cell growth. Two groups of mice were treated with strains of S. epidermidis.
There were two strains of S. epidermidis: one strain that makes the 6-HAP
molecule and one strain that does not. Then, the mice were exposed with UV
rays. The skin of the mice that were treated with the 6-HAP producing bacteria remained
normal while the skin of mice that were treated with the strain that did not
produce 6-HAP developed UV-induced tumors.
Gallo furthered his research by studying the effect 6-HAP
had on cancer cells and their run away growth. They found that 6-HAP indeed
stopped the DNA formation of various tumors cells that they had grown in the
lab. Meanwhile, 6-HAP does not affect the growth of normal skin cells as they
produce an enzyme (mitochondrial amidoxime reducing components) that deactivate
6-HAP.
The methods for applying the strain of S. epidermidis
include either injection or a topical application.
The study then examined the prevention of tumor growth by
again testing 2 groups of mice: a group that was given a S. epidermidis strain
that produced 6-HAP and a group that was given a strain that did not. After
periodic exposure to UV rays for 12 weeks, the mice that were given the 6-HAP
producing strain developed only one tumor each while the other group of mice
developed 4-6 tumors each.
Of course more research needs to be done to further study how
6-HAP is produced and how it can be utilized, but Gallo and his colleagues’
current studies shows promising steps towards skin cancer prevention. Could the
use of probiotics for the skin be in the future? A slather of beneficial/preventative
bacteria to ward off infection or decrease one’s risk for cancer?
http://advances.sciencemag.org/content/4/2/eaao4502
A bacteria preventing cell growth? That's incredible! Call me naive, but I had no idea that the microbiome could be so influential on the human body. A probiotic preventing skin cancer, that would be a fantastic breakthrough that could help everyone. Great post!
ReplyDeleteWoah, that's cool. Staph has always been seen as something that is genterally negative, as it is usually associated with Staph infection. But to think that it could actually be beneficial and used to prevent cancer is really cool!
ReplyDeleteThat's a very interesting study that you found. It makes me wonder how much of a role bacteria plays in our everyday life. I feel like more tests should be done on different types of bacteria to see what kind of role they have on the outside and the inside of our body. In a couple of weeks, I feel like we will be exposed to a lot of research regarding our microbiome when groups present for the symposium
ReplyDeleteYes, I agree that there is much research to be done on the microbiome and how it relates to our well being - you never now there might be some type of bacteria that is twice as benefical but is yet to be discovered!
DeleteI never would have though about a typically negative bacteria being able to have such a positive effect! But I guess that just goes to show you how diverse the bacteria population is and how it truly comes down to the species rather than stereotyping the entire genus. This could be such a wonderful ingredient in sun protection if proven topical application has the same power as injections. It makes you wonder how many other species of bacteria out there can have the same beneficial effects in other ways than preventing skin tumors.
ReplyDeleteWith that being said, I think that new applications of preventative measures for illness are bound to happen and that the application of positive reinforcement of the microbiome is a cool topic to think about.
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