Ribosomes are found in every cell of every living thing. They are the cell’s construction workers, decoding the DNA blueprints and building proteins. These proteins are used for all sorts of functions such as muscle contraction, controlling the immune system, or transmitting signals between nerves.
It was previously thought that ribosomes are identical within an organism, however BC Cancer researcher Artem Babaian was able to tease apart that cancer cells have their own type of ribosome, not found in healthy cells.
His study, published today in Cell Reports found that some of the ribosomes inside cancer cells are missing a key modification that affects how ribosomes “read” the blueprint. This difference in the cancer cell’s ribosomes means the cells make more of some proteins, specifically, the proteins to make more ribosomes.
It’s like the construction worker is making too many construction workers and in cancer this means the cells grow quickly.
“There was this single RNA nucleotide that was statistically very, very different in cancer cells compared to normal cells… and then the whole study had to pivot and go in an unexpected way,” says Dr. Babaian. “Cancer cells lose this modification. This is significant because all Eukaryote cells, meaning all animals, fungi, and plants, are supposed to have this. Human cancer cells have less than normal, with some having almost none at all, and that’s the big difference I found.”
Dr. Babaian tested over 10,000 tumours from 32 different types of cancer and found that at least 22 cancers had these altered ribosome to some extent, including 45% of colorectal cancers, 30% of lymphomas, and 10% of lung cancers that were tested.
Knowing that some antibiotics work by shutting off bacterial ribosomes while not affecting human ribosomes, Dr. Babian is now testing a hypothesis that perhaps it’s possible to develop a ‘cancer antibiotic’ against these cancer ribosomes.
“The same way that we know antibiotics works on bacterial cells,” says Babaian, “it opens up the avenue that you could create a similar ribosome inhibitor for cancer. That’s the big picture – right now I’m trying to understand why this change happens in cancer and see if there are available drugs to target that change.”