Staphylococcus epidermidis (S. epidermidis) is a bacteria commonly found on healthy human skin. Scientists have now discovered that a strain of S. epidermidis can stop the growth of some cancers.
In the research published in Science Advances, it was reported that S. epidermidis strains isolated from human skin produce a chemical called 6-N-hydroxyaminopurine (6-HAP). 6-HAP stops DNA synthesis, which prevents cancer cells from multiplying.
Mice colonised with a strain of S. epidermidis that did not make 6-HAP developed many skin tumors after being exposed to UV rays (which causes skin cancer). On the other hand, mice colonised with S. epidermidis that do produce 6-HAP had significantly less tumors.
The researchers also tested the effects of 6-HAP in mice transplanted with melanoma cells. They injected a group of these mice with 6-HAP (dose: 20mg/kg every 48 hours for 2 weeks), while another group did not receive 6-HAP. They found that in mice receiving 6-HAP, the tumor size was suppressed by over 60% compared to mice that did not receive 6-HAP. The researchers did not find any toxic side-effects associated with 6-HAP.
Last year, the same team who conducted this study reported that bacteria collected from human skin also showed anti-microbial activity that could protect the skin against pathogens. Here’s a link to the study.
Note that although the S. epidermidis in this study was collected from the skin of human samples, the anti-cancer properties have only been tested in mice at this point. Further study in humans are still yet to be conducted.