I talk about how viruses and endogenous retroviruses can cause cancer (and all kinds of other diseases) all the time here on ERV. But one thing I hope I highlight for you all as well is how the scientific community can use viruses as a tool. We can take advantage of their evolved tricks and our immune systems evolved tricks to create systems to treat diseases that have nothing at all to do with viruses or their associated diseases. Turn the tables on parasites– use them for our advantage.
Here is another neat idea involving RNA viruses and cancer:
RNA viruses have a stage in their life-cycle that is unlike anything found in eukaryotes– They have to use one RNA strand to create more RNA which requires an RNA-RNA polymerase, and creates dsRNA. You have no RNA-RNA polymerase. You have no dsRNA. So your cells have pattern recognition sensors whos sole job is to look for dsRNA, aka viral infection. If a cell senses dsRNA in its guts, it kills itself, and sends out warning flares to all the cells around it “OMFG U GUAIS I IZ INFECTED U MITE BE INFECTED AAAAAAAAAARRGURGLEDEAD!”
What does this have to do with cancers?
Well, some tumors stumble upon ways to evade your immune system. Apparently its not that hard, because they all figure out some way to do it.
So these researchers thought “What if we could take the immune system out of the picture? What if we could get the tumor to kill itself?” And thats where viruses come in. They delivered chemically treated DNA (to get the cells to suck it up) that coded for the front end of a virus– the part that codes for the RNA-RNA polymerase. Once that DNA was in the tumor, the RNA-RNA polymerase was made, which made lots and lots of dsRNA. Even tumor cells knows dsRNA is fucked up, and the tumors killed themselves.
There are other pattern-recognition sentinels in your cells. All of your DNA is methylated (epigenetics). Bacterial DNA that you prep in the lab isnt. So when the artificial DNA was introduced into the tumors, even without making any RNA-RNA polymerase, the non-methylated DNA activated the ‘WE GOTS BACTERIA PEOPLES! WE GOTS NON-METHYLATED DNA HERE! I KIL MAISELFS NAU!’ alarms in the tumors.
They used this experimental treatment on 5 mice. The ‘viral’ dsRNA and the ‘bacterial’ non-methylated DNA successfully convinced the tumors to commit suicide. All five mice were alive and tumor-free by the end of the protocol. One out of five control mice was still alive (and had a ~9 mm tumor), 2/5 control plasmid mice were still alive (also with large tumors).
Yes, there are lots of ‘problems’ with this paper– only five mice per group, its ‘only in mice’, this would only work for ‘HI! IM A SINGLE TUMOR MASS!’ tumors, and not the twisty crazy hard-to-operate on tumor masses or blood-cancers, but its a neat example of how we can take a chunk of virus, a chunk of your immune response to viruses and bacteria, and use em to clear a tumor thats got nothing to do with microbiology at all.
Viruses arent just pests– they are technology.