Weird ‘harmless’ microbes may play a pivotal role in colorectal cancer

The mysterious ancient microorganisms which are neither bacteria nor viruses seem to play a role in colorectal cancer. This supports the idea that such microbes, which were considered harmless, could in fact be involved in human diseases.

There are three areas of life. The first includes unicellular bacteria. The second is made up of organisms called eukaryotes which are often multicellular, including all animals and plants. These have larger cells filled with internal structures, including a nucleus filled with DNA.

Archaea is the third area. These are unicellular organisms that were originally considered bacteria because they have no nucleus, but who proved to be sharing certain similarities with eukaryotes. In fact, we now think that the first eukaryotes may have been archaea who swallowed free bacteria.

Although the thousands of bacteria and viruses hiding in our intestine have been linked to many conditions – including cancer, diabetes, obesity and heart disease – the archaea that lives are not normally examined for such associations.

“Most scientists working on the human microbiome ignore archaees and completely filter these organisms,” said Roxy Mohammadzadeh at the Graz Medical University in Austria. However, a high number of archaea occurs alongside conditions such as colorectal cancer, Parkinson’s disease and infections of gums and urinary tract.

To better understand these associations, Mohammadzadeh and his colleagues have looked for archaean signatures of the disease in 19 clinical studies covering more than 1,800 individuals.

They found that the associations between Archaea and a range of medical conditions are common but variable. However, they discovered a coherent increase in an archeon called Methanobrevibacter Smithii in people with colorectal cancer. This organization plays a big role in our digestion by consuming bacterial fermentation products, such as hydrogen and carbon dioxide, and the liberation of methane.

The team found, via modeling and cultivating microbes, that M. smithiii interaci with bacteria, including Fragilis bacteroides,, Escherichia coli And Fusobacterium nuleatum.

These three species have already been linked to colorectal cancer, but it was the relationship with F. Nuleatum It seemed the most notable. In the presence of M. smithiii,, F. Nuleatum Much more of a compound known as succinat, a critical metabolic signaling molecule. However, in cancer succinat, succinat is known to improve the invasive tumor way and its propagation potential.

“These are the first mechanistic evidence showing the role of the archée on human diseases and in particular colorectal cancer,” explains Mohammadzadeh.

This study supports previous work Mr. Smithii With colorectal cancer, known as Gianmarco Piccinno at the University of Trento in Italy. But given that most of the evidence so far are only correlational, it says that additional research is necessary to determine any cancer cancer mechanism and why people with colorectal cancer have more of this microbe.

“While archaea have been recognized as components of the human microbiome, their direct involvement in the disease has remained poorly understood,” said Sunny Wong at the Nanyang Technological University in Singapore, which also recently reported links between Archaea and colorectal cancer. “Although there were much smaller in number than bacteria in the intestine, they are metabolically active and often consume hydrogen, produce methane and interact with bacteria, as well as the host.”