Low Oxygen Cellular Protein Synthesis Mechanism Discovered
New submitter _prime writes "Until recently the mechanism by which cells make proteins in low-oxygen environments has been unknown. As published in Nature (paywall) this week, the discovery of the mechanism by an Ottawa-based team of researchers potentially means it could be 'very easy to kill cancer cells' without harming normal cells because cancer cells leverage the same low-oxygen protein synthesis mechanism even in the presence of normal oxygen levels."
One of the main problems cancer cells have is getting enough oxygen.
Their continuous unregulated reproduction outgrows their blood supply - and while a typical tumor signals for more blood vessel growth (vascularization) into itself, the vessels themselves are organized so they can't really keep up. The result is that the bulk of a solid tumor is running on very low oxygen concentration, the main limit on its growth is its ability to obtain new vascularization, and a substantial fraction of the cancer cells may be dying off due to this oxygen shortage.
So of course having essentially every low-oxygen hack available turned on is a reasonable thing to expect of dangerous tumor types. And turning them off, even through it might not completely kill the tumor, would knock it down enormously AND the remainder would be expected to be far more vulnerable to the body's immune system.
(Of course if the tumor is a type that recognizes it should die but is evading apoptosis because that works on the normal but not the low-oxygen pathway, turning off the low-oxygen pathway means the cancer cells should just commit suicide, either completely killing the tumor or knocking it back to a miniscule number of cells with further mutations.)
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Mod parent up. I just signed up for an account to say exactly the same thing.
To add to this, the major thing about Warburg metabolism is that not only does it allow cancer cells to survive in low-oxygen conditions; it actually produces the raw materials for making the protein needed to grow new cancer cells, so it allows cancer cells to grow faster than if they were using normal aerobic respiration. Here's James Watson talking about it in the NYT. So the low-oxygen conditions in a tumour are an evolutionary selection pressure for tumours to evolve towards dealing with low-oxygen conditions, but probably also for them to evolve towards growing faster and being more malignant too.
In the study in the OP they already knew the normal gubbins that engages the services of the protein-making machinery doesn't work in low-oxygen conditions, so they went looking for something that does work under these conditions and found it. It normally exists in cells so that they can make proteins when starved of oxygen. What's not clear from the Nature abstract, and what will probably need more work to study, is whether this pathway is massively boosted in cancer cells. My guess is that it will be. The Warburg effect is interesting and unique to cancer cells, but it's difficult to turn into a treatment as it's a perversion of a pathway that's essential in all cells - if you drug the pathway itself you'll likely kill the patient. This study is different as it's a pathway that's specific to oxygen-starved cells, so it may well (in about 20 years) provide some exciting new 'universal' drug targets for solid tumours, that may not kill them dead but might at least slow them down. Don't take up smoking yet though...