Gut bacteria alter gene expression and potentially cut cancer risk

New research has shown a connection between the potential role of gut bacteria having an active role in gene expression and in turn reducing the risk of cancer.

Dr Patrick Varga-Weisz at Babraham Institute in Cambridge led a team of scientists and found that a by-product made by bacteria while digesting fruits and vegetables – short chain fatty acids (SCFAs) – in our gut can impact our gene activity. 

The experiments were carried out in mice and human culture cells. The study found that a protein HDAC2 changes gene expression by modifying proteins associated with the DNA through a process called crotonylation. 

Higher levels of HDAC2 have been previously associated with a greater risk of colorectal cancer. The researchers added SCFAs directly to cancerous human colon cells in a dish, and found that this inhibited HDAC2. In another experiment, mice on antibiotics were found to have higher levels of HDAC2. 

SCFAs are vital to maintaining normal gut health by providing a major energy source for the cells in the lining of the gut. However, this is the first time that they have been shown to have an important role in cancer risk reduction. 

'SCFAs are a key energy source for cells in the gut but we've also shown they affect crotonylation of the genome,' said study first author Dr Rachel Fellows.

'Our study reveals why this is the case by identifying a new role for HDAC2. This, in turn, has been implicated in cancer and offers an interesting new drug target to be studied further.'

As the gut bacteria community proves to play a key role in many aspects of our health from weight maintenance to identifying a unique microbial fingerprint (see BioNews 802) and now a preventative role in reducing the risk of cancer. 

The study is published in the journal Nature Communications.