Researchers engineer bacteria to detect cancer

Researchers have found a way to manipulate bacteria to identify bowel cancer in its early stages. A particular species of bacteria can be engineered to detect specific mutations in human DNA.

A study, published in the journal Science, shows that wherever cancer may lurk in the bowels of the human body, an engineered microbe could one day detect it.

The researchers are focusing on making this bacteria function as a probiotic sensor in the gut to diligently inspect, detect and report any intestinal ailments.

The team led by biologist Robert Cooper at the University of California, San Diego, has successfully engineered a species of bacteria named Acinetobacter baylyi. This bacteria, known for its ability to absorb DNA from their surroundings, has been programmed to seek specific DNA sequences common in colorectal cancers.

When it incorporates tumour DNA into its system, an antibiotic-resistance gene gets activated. This gene allows the bacteria to grow on antibiotic-containing agar plates extracted from faeces, indicating the presence of cancer cells.

The research is still in its infancy and it could be some time until the method is approved for clinical trials.

Furthermore, the effectiveness and safety of the engineered bacteria still need to be meticulously tested.

Currently, the bacteria is being programmed to detect KRAS mutations, prevalent in about 40 per cent of colorectal cancers, some lung cancers and most pancreas cancers.

For it to actually be useful in humans, researchers need to provide evidence of A. baylyi being safe for oral consumption, and demonstrating consistent results in detecting cancer cells in fecal samples.

The level of effectiveness of this bacterial biosensor in comparison to colonoscopy, a more invasive diagnostic procedure, needs to be examined as well.

This breakthrough comes at a crucial time as bowel cancer rates are rising and early detection in adults under 50 is of paramount importance.