A number of previous studies have found that the roughly 400 olfactory genes present in the human body are sometimes expressed beyond the nose, posing an interesting question for researchers involved in the field of genetics.
Now, a study published in Molecular Systems Biology has shown that patients with colon cancer whose cells exhibit the expression of certain smell-sensing genes are more likely to suffer more serious illness and have worse outcomes.
The expression of a gene simply means the deployment of the information contained therein for making proteins or other molecules with specific effects in the body. To study the effects of individual genes within a cell, researchers use experimental techniques called “perturbations”.
When expressed in parts of the body beyond the nose, smell-sensing genes can give cancer cells a 'sixth sense' for which cell to invade next. Image: pikrepo.com, CC0
Dr. Heba Sailem, Sir Henry Wellcome Research Fellow at the Institute of Biomedical Engineering and lead author on the study, had this to say about the importance of assessing how cells are organised in body tissue when researching the development of cancer:
“Cancer is often characterised with the loss of tissue structure which can be driven by certain gene alterations or stresses. It is crucial to understand which genes play a role in this process to be able to develop therapies that target cancer development”.
By using multiple layers of AI that were fed information from robotic microscopy to image millions of colon cancer cells, the researchers found that smell-sensing genes, when expressed within a cell, have a strong impact on how it spreads and aligns with other cells.
The more robust the expression of these genes, the more rapid the development of cancer, and vice versa. Study authors speculate this effect to be related to how the smell-sensing genes regulate cell motility.
“It is like activating a sixth sense that allows cancer cells to smell their way outside the toxic tumour environment which can result in spreading cancer to other parts of the body and make things worse for the patient,” Dr. Sailem said.
Without AI, the study would have taken much longer – and might have provided less accurate results – relegating experts to the laborious task of manually identifying examples of changes in cell appearance one-by-one.
In combination with gene editing technologies, such as CRISPR, studies like this will likely be vital in understanding how cancer works and developing effective treatments.
Sources: study, eng.ox.ac.uk