The human body and microorganisms are inseparable, we have already lived with microbes even if when we are still in the womb. The number of microbes in the intestine is even greater than the number of cells in the human body, and the largest organ of human body – the skin, is a huge environment for another microbial activity. Recently, an article published by the researchers from the University of California, San Diego found that S.epidermidis, which is located on the surface of human skin, actually has the effect of fighting cancer. The related result is published in the latest issue of the international academic journal Science Progress.
In the past, we did not realize the benefits of microorganisms, but the benefits of microbes in the human body are being further revealed by the in-depth development of intestinal microbiology research. However, the importance of microbes on the surface of the skin is far inferior to that of intestinal microbes as they will be washed clean with the daily bath. New research shows that microbes on the surface of the skin are not useless, they can even provide new ideas for the treatment of human cancers.
How does S.epidermidis fight cancer?
Researchers have found that S.epidermidis can secrete a substance named 6-N-hydroxyaminopurine (6-HAP) that blocks the activity of DNA polymerase and causes DNA synthesis barriers. Therefore, once the proliferation of tumor cells is inhibited by DNA synthesis, naturally, it will not be able to divide and proliferate.
6-N-hydroxyaminopurine (6-HAP) is effective in inhibiting the proliferation of lymphoma, melanoma, and cutaneous squamous cell carcinoma. The key is that 6-HAP will not be toxicity to normal cells. Professor Richard L. Gallo, the corresponding author of this article said that, ‘The chemicals produced by this unique skin bacteria kill several types of cancer cells but are not toxic to normal cells.’
Experiments in Mice
Researchers also conducted experiments on animals to verify whether 6-HAP can inhibit tumor cell growth. They injected 6-HAP directly into the blood of mice with melanoma and found that 6-HAP can effectively inhibit the growth of tumors in mice. But will they be effective to fight the tumor if the S.epidermidis being applied directly to the skin? The researchers then used ultraviolet light to irradiate the mice (so that mice can develop skin cancer), then smeared S.epidermidis that produces 6-HAP and bacteria that are not capable of producing 6-HAP, respectively. The results showed that mice smeared with S.epidermidis had almost no tumors on their skin, whereas mice in the control group were covered with tumors.
The distribution of this kind of bacteria
The researchers further adopted sequencing technologies and bioinformatics analysis found that this kind of S.epidermidis that can produce 6-HAP is widely distributed in various parts of human body, such as the Plantar heel, Glabella, Toenail, Retroauricular crease, Toe web space etc. ‘The existence of this strain may be to provide natural protection, and it is possible to be applied in the treatment and inhibition of various forms of cancer,’ Professor Richard L. Gallo said.
Lindsay Kalan, a biochemist at the University of Wisconsin-Madison, believes that this discovery highlights the potential of the microbiome to affect human disease.