A new study from McGill University is taking science one step closer to understanding how metastatic cancer spreads through the body, something researchers hope could lead to new treatments.
Researchers dug into the function of specific proteins — called phosphates of regenerating liver (PRLs) — which appear in countless creatures from humans to fruit flies, in order to track how they facilitate cancer growth.
Previous research has demonstrated that these proteins, which play a role in cell growth and metabolism, show up in overwhelming numbers in some cancers.
“It's important for us to study PRLs because they are so important in cancer,” Dr. Kalle Gehring, professor of biochemistry and founding director of the McGill Centre for Structural Biology, said in a press release. “In some cancers, like metastatic colorectal cancer, the proteins are overexpressed up to 300-fold.”
Overexpression in cellular biology refers to when there are too many copies made of a protein or other substance. Cancer occurs when cells replicate themselves uncontrollably and that tissue then starts growing into other parts of the body.
The fact that PRLs are so over-represented within cancerous tissue has meant they have long been thought of as a target for cancer treatments, Gehring explained.
In the new study, published this month in the peer-reviewed Journal of Biological Chemistry, researchers set out to understand whether or not the way PRLs function is specific to human cells, or if these properties are found across the numerous other organisms these are found within.
“This conservation of a feature across species and evolution is a strong indication of the importance,” Gehring said in a video release.
Researchers studied the proteins across 15 organisms, including humans, single-celled organisms, zebrafish and some plants, and confirmed that PRLs are present in all of them.
One species they took an in-depth look at couldn’t be more different than humans: fruit flies.
But even in these insects, there was one aspect of PRLs which was identical to the one found in humans.
“What we learned is that they all bind the magnesium transporters in the same way,” said Gehring.
The fact that this binding technique is preserved across so many different species suggests the way these proteins bind is central to their functioning within a body, and gives a much clearer idea of how scientists might be able to design drugs to shut these proteins down if need be.
“We're excited because it helps us understand this pathway, and that will reveal new targets for drugs to prevent cancer progression,” Gehring said.
The research was made possible by data collected at the Canadian Light Source (CLS) at the University of Saskatchewan. The research facility contains an instrument capable of producing the brightest light in the country, millions of times brighter than the Sun.
It’s called a synchrotron, and the different wavelengths and intensity of light it produces allows researchers to study the structural and chemical properties of things on the molecular level.
Using this data, Gehring and his team were able to compare the structures of PRLs across numerous species and observe differences and similarities more easily.
“We've been working with the CLS for many years and always had very positive experiences,” Gehring said. “The facility is world-class and really essential for biomedical research in Canada.”
