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If I could add more of any cell to my body, there are a lot of good choices, but I'd want more brain cells. And if I could get rid of any kind of cell from the human body in general, my first choice would be cancer cells. Which is why I'm so excited about this research that literally turns horrible cancer cells into amazing brain cells! We're on the road to making some of the deadliest stuff on earth less deadly, and in return we get more functional brain cells. Take that, cancer! [♪ INTRO] There are a lot of cancers that used to be a death sentence. But with modern screening practices and the triple threat of surgery, chemotherapy, and radiation, many people live years beyond an initial cancer diagnosis.
Glioblastoma is not one of those cancers. It has a median survival time of 15-18 months after diagnosis. Partly because it's especially hard to treat. It grows in this really hard to reach area, behind a wall of bone. AKA your skull. Plus, if you manage to breach that wall, so much of the stuff behind it is critical. You don't want to take out the part of your brain that stores all of your memories or keeps your balance while you move around unless you really have to. While that makes surgery harder, it's less of a problem for chemotherapy,
which can go through your blood, naturally circulating to your brain anyway. The issue with chemo is a little thing called the blood-brain barrier. See, if anything manages to make its way into your bloodstream, your body still has some defenses against letting it into your brain. You have a tightly-packed layer of cells that prevents certain large molecules from flooding your brain. …And that means fewer chemotherapy options. Then you're left with radiotherapy, which might entail daily localized doses of radiation for a few months.
This kills your cells by damaging their DNA. Considering the limitations of cancer treatment in your brain compared with the rest of your body, this combo of surgery, chemo, and radiation is often not enough. Some of the cancer cells usually survive. And glioblastoma is almost always deadly. But maybe, just maybe, there's a way we can make those cancer cells that remain less deadly… by making them more like regular brain cells. Now, when I say "regular brain cells," that can mean a few different things. You've got your neurons signalling away and you've also got glia acting as your brain's immune cells.
Each of these cells started out as neural stem cells and turned into neurons and glia thanks to molecules like cAMP. Normally, those new brain cells will then go off to perform healthy brain functions. No cancer. No worries. Well, like worrying is actually like a literal function of your brain, so maybe just no cancer. Except when things go awry. After stem cells have differentiated into glia, those glial cells can start replicating out of control to form glioblastomas. This is something we're desperately trying to reverse in laboratories across the world.
Several research teams have attempted therapies to get these glioblastoma cells to go back to their pre-cancer selves …with limited success. So a research group at UCLA set their sights on nudging those glioblastoma cells back into their previous, non-lethal life stages. With a not-so-novel step one: radiation. But before we can explain how they're working on solving this incredibly difficult problem, it's time for a quick ad. You watch SciShow. So we know you're curious and you think it's good to learn new stuff. We also know you're into the idea of learning online. And all of that means you also sound like a Brilliant subscriber.
Brilliant is an online learning platform made for everyone from age 10 to 110. And they offer courses that strengthen your math skills, like Coordinate Transformations, which includes 60 lessons and 780 exercises. To give you an idea of just how interactive Brilliant is. To learn for free on Brilliant for 30 days, go to brilliant.org/scishow, scan the QR code onscreen, or click on the link in the description. Brilliant's also given our viewers 20% off an annual Premium subscription, which gives you unlimited daily access to everything on Brilliant. From previous work, the UCLA group knew that the glioblastoma cells
left behind after radiation were in a more stem cell-like state. So they irradiated glioblastoma cells, and then added a cAMP analog. Which is just a molecule very similar to cAMP. And it worked! The previously cancerous cells treated with radiation followed by the cAMP analog looked a lot like neurons. They had that characteristic spindly shape and they were creating proteins normally only found in neurons. They seemed like they were once again law-abiding citizens of Braintopia. But we don't quite have the data to say they were just like their former selves. And even if we did, there's a bigger problem: this cAMP analog has a pretty short half-life.
Basically, it would get broken down before much of it could even reach the glioblastoma. To get around this problem, the research team tried boosting an enzyme that makes cAMP instead. After all, the outcome should be the same: more cAMP. And we already have a tried and true way of doing that. It's a molecule with a longer half life than cAMP. And it can cross the blood-brain barrier. It's called forskolin. When the same research team irradiated cells and added forskolin to the mix, it had pretty much the same effect as treating with radiation plus the cAMP analog: neuron-like shapes and proteins.
Plus they were no longer dividing like they had been! Which brought us even closer to turning glioblastomas into regular brain cells. They definitely were not growing tumors anymore. So it was time to take these lessons out of the controlled environment of a dish and into real living animals. When they tested out this new radiation/forskolin combo treatment on mice with glioblastoma, it increased the average mouse's survival from 36 days to 129 days! That's more than three times longer! Which meant they had enough evidence behind them to see how this treatment would work with human cells inside a body.
So the researchers implanted human glioblastoma cells into mouse brains. Just inching closer to seeing how this would work for people diagnosed with glioblastoma. In these mice, the combo treatment reduced their glioblastoma cell count. And the ones left over were going back to their pre-cancer ways. But unfortunately, the incredible mouse glioblastoma results didn't go quite as far for human glioblastoma. The average survival only increased a little, from 34 to 48 days. So it kind of works at this stage, but there's still plenty to be sorted out.
Maybe a higher dose of forskolin would do the trick. Or maybe cAMP isn't enough on its own to properly differentiate stem cells into neurons. After all, when your brain is developing, cAMP works alongside a bunch of other small signaling proteins. So we might need an even combo-y-er combo treatment. Where the research stands right now, we have an awesome new treatment for mice with glioblastoma. It does the unthinkable and trades your least favorite cells for pretty close to the best possible alternatives. But we're still a few steps away from seeing that happen in your body or mine. Which gives us some time to figure out what
we would do with the extra brain power. [♪ OUTRO]
