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But the cancer can't survive if the immune system recognizes it.

So eventually what happens is there's this detente that is reached between the immune system and the cancer where the immune system basically ignores the cancer.

So Jim Allison here in Houston won the Nobel Prize back in 2018.

for understanding one of these turn-off signals that the immune system, that the cancer is used to turn off the immune system, and that by showing he could block it, his wife, Pam Sharma, ran a bunch of clinical trials at MD Anderson that showed, in fact, that this could actually turn a 5% survival disease in melanoma to a 50% survival.

And that then created the whole immunotherapy field that the world is taking advantage of today.

So for instance, there are proteins on your cell surface, and we'll get too immunologically deep about it.

They're called major histocompatibility complex proteins.

So for instance, if I were to try to just randomly do a tissue transplant from me to you,

it's very likely that it would be rejected.

And it's because of those MHC proteins that it's rejected.

What's happening is that your cells are presenting your internal cell biology to the immune system, and it's saying, okay, you're a friend, not a foe.

So when cancer usually initiates, there are disruptions that happen and proteins are made incorrectly, et cetera.

And so what these MHC proteins are doing in some cases is they're presenting the internal damage to the body and the body is saying, oh, there's something wrong with this cell.

We better wipe it out.

We kill it.

These same proteins are what the immune system uses, for instance, to go after viruses.

So when you get a virus infection inside of the cell, the body has a way of chopping those proteins up inside of the cell, presenting it via MHC, and then the immune system attacks it.

So one of the first things that actually tumors do is they learn to turn off the MHC proteins inside of themselves.

So the ability to show that I'm damaged is shut down.

And so the immune system doesn't go on full alert for that.