Just to make this clear up front:
WHAT I AM ABOUT TO WRITE ABOUT IS NOT A ‘CURE’ FOR CANCER. ITS A NEAT IDEA WE MIGHT BE ABLE TO CAPITALIZE ON IN THE FUTURE. ITS COOL! NOT A ‘CURE’.
Perfect example of the potential domesticated viruses have to tame deadly diseases!
Tumor Cell Marker PVRL4 (Nectin 4) Is an Epithelial Cell Receptor for Measles Virus
… only the human tumor cell marker PVRL4 (Nectin 4) rendered cells amenable to measles virus infections… It is highly expressed on many lung, breast, colon, and ovarian tumors suggesting that they could be targeted with oncolytic measles virus.
Some of the measles viruses we use in the lab and in vaccines, they dont behave ‘normally’. Its not in an ‘Outbreak‘-like bad way– its more like they had a ‘posh’ upbringing in the lab, while their ‘natural’ relatives had a much harder life. Because they grew up with a silver pipette in their measle-mouths, they had the luxury to explore options untamed viruses couldnt. We capitalize on this, on purpose, to attenuate viruses for use in vaccines.
But there was a neat side-effect with measles. Maybe because we grow viruses in cell lines in the labs, and cell lines are kinda like tumors, some measles viruses can use a protein, PVRL4, on the surface of some tumors to initiate infection. PVRL4 is a totally normal human protein that is expressed in certain cells at certain times. But cancers are all kinds of messed up. They behave in ways ‘normal’ tissue shouldnt, and they likewise make proteins they arent supposed to make, like PVRL4.
So some kinds of measles can use PVRL4 to infect cells… and well, measles kills the cells it infects… including the tumor cells! Especially adenocarcinomas, apparently! Its not that we could use measles to deliver an anti-cancer drug or gene to tell the tumor to commit suicide or something– measles is naturally lytic, thus ‘naturally’ oncolytic! It just kills the cancer, all on its own.
This paper was very thorough in determining the receptor measles was using to perform this trick, and figuring out which cells measles could be used on. But it is all just in cells in the lab. Lab ≠ Real World Therapy.
But other folks have been trying it out in animal models! Mice that have been grafted with human tumors! And according to those authors, ‘Clinical trials using vaccine measles virus (MV) as anticancer therapy are already underway.’
I have no idea how those clinicians are getting around the fact everyone has antibodies to measles (if your immune system kills measles before it can kill your tumor, hows it gonna work?), but I cant wait to see how this turns out!