A study published in the journal Molecular Systems Biology has revealed a novel role for smell-sensing genes in colorectal cancer.

The study showed that the expression of certain smell sensing genes in colorectal cancer cells correlates with worse patient outcomes especially in those with higher-grade tumours.

Humans have around 400 smell-sensing genes.

The activation of different combinations of these genes in the nose allows us to smell a wide variety of scents.

However, these genes are also expressed in different tissues other than the nose, but their role remained a mystery.

Researchers at the University of Oxford developed a computer vision algorithm that can characterise the organisation of cells in proximity to each other.

The leader author Dr Heba Sailem said: “Cancer is often characterised by the loss of tissue structure which can be driven by certain genetic alterations or stresses. It is crucial to understand what are the genes that play a role in this process in different tissue types to be able to develop therapies that target cancer development."

The researchers used robotic microscopy to study the behaviour of millions of cells that were imaged following the perturbation of every single gene in colon cancer cells.

The study found that smell-sensing genes are strongly associated with how cells spread and align with each other and potentially affect cell motility.

The same behaviour is also observed when perturbing key cancer genes.

“It is like activating a sixth sense that allows cancer cells to smell their way outside the toxic tumour environment which results in spreading cancer to other parts of the body and make things worse for the patient” Dr Sailem said.

An intelligent system was built to teach the computer what are the visual cues that can be used to distinguish images of abnormal cells based on the knowledge human accumulated on gene functions over tens of years.

Parallel with advances in gene editing technologies, such as CRISPR, such a system can enable new avenues for cancer therapy and understanding how genetic alterations drive cancer development.

Source: University of Oxford