SKIN BACTERIA could provide protection from several types of cancer, according to the results of a new study carried out at the University of California, San Diego, California, USA. The skin is naturally covered in bacteria, with approximately 1 million bacteria per cm2 of skin, and these bacteria have long been associated with health and disease, including the development of eczema; however, this new study has attributed anti-cancer capabilities to certain strains of skin bacteria.
Skin bacteria from volunteers were cultured and their properties analysed. While some of the cultured bacteria produced antibacterial proteins when introduced to harmful bacteria, it was observed that Staphylococcus epidermidis produced the chemical compound 6-N-hydroxyaminopurine (6–HAP), which is very similar in structure to anti-blood cancer therapies used today. The 6-HAP compound was shown to have potent tumouricidal effects.
The compound was tested in vivo by injecting it into mice with skin tumours every 48 hours for 2 weeks, while control mice were injected with saline. By inhibiting the synthesis of DNA, 6-HAP was shown to decrease the size of the tumours by 60%. Furthermore, following exposure to ultraviolet light it was revealed that mice with a 6-HAP-producing strain of S. epidermidis developed around 20% fewer tumours than mice with the S. epidermidis strain without 6-HAP production.
There is an increasing volume of work investigating the use of the immune system to combat cancers, but it is important not to forget the impact of the microbiome on human health. “There is increasing evidence that the skin microbiome is an important element of human health. In fact, we previously reported that some bacteria on our skin produce antimicrobial peptides that defend against pathogenic bacteria, such as Staphylococcus aureus,” commented Prof Richard Gallo, University of California. With >1 million new cases of skin cancer diagnosed each year in the USA, the beneficial effects of 6-HAP-synthesising bacteria could prove to be a very useful weapon in the ever-evolving battle with cancer.