Scientists have found a new way of triggering the death of cancer cells, using the body’s own cell-clearing function. By harnessing the activity of a protein called Bak – known for its function as the biological assassin that kills off old, dysfunctional cells – the Australian team has figured out how to turn the killer protein on cancer cells instead.
“We were excited when we realised we had found an entirely new way of activating Bak,” said one of the researchers, Ruth Kluck, from the Walter and Eliza Hall Institute of Medical Research
Bak is used by our bodies in the normal, programmed cell-death process known as apoptosis. Apoptosis removes unwanted cells from our insides, but when it fails to kick into action, cancer cells are allowed to spread unchecked.
Using information about Bak’s three-dimensional structure, the team discovered that a certain antibody could bind itself to the Bak protein and activate it, leading them to investigate if they could control where the protein would strike.
“There is great interest in developing drugs that trigger Bak activation to treat diseases such as cancer where apoptosis has gone awry,” says Kluck. “This discovery gives us a new starting point for developing therapies that directly activate Bak and cause cell death.”
Scientists already knew that a class of proteins called BH3-only proteins could be used to send Bak into action, but they now have a new activation site to work with. The next stage is to develop the antibody into a drug that targets Bak inside cells, and to test it in living models.
Autoimmune diseases could also be treated using the same drugs. In autoimmune diseases, a breakdown in the apoptosis also allows immune cells to inappropriately attack the body, so Bak could be harnessed to kill of those cells too, the researchers report.
It’s exciting times for cancer research, as scientists chip away at the disease bit by bit, discovering new possibilities for more effective and personalised treatment options beyond chemo and radiotherapy.
From the development of nano-carriers that can carry chemo drugs directly into brain cells, to a better understanding of what causes cancer in the first place, progress is constantly being made in our fight to better understand the root causes of this disease. That progress now includes this new Bak-activating antibody, which will hopefully continue to show potential as the researchers develop it further.
The study has been published in Nature Communications.