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This week, researchers announced a novel cancer drug has become the first of its kind to reach clinical trials. Also, new research into vampire bat friendships could help us learn more about animal (and human) behavior.

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This week in the journal Nature, researchers announced that a novel cancer drug is making progress in clinical trials. The drug targets a growth pathway that's proven difficult in the past, potentially giving us a new way to treat cancers with specific mutations.

Now cancer, in its most basic sense, happens when normal cells start growing out of control. There are a lot of different reasons why this happens, so cancer, it turns out, is many different things. Often, the culprit is a mutation in a gene that controls cell growth.

If that gene goes haywire, cell growth can too, and that can create a tumor. But recently, a drug designed to target one of those haywire genes began clinical trials. The gene in question is called KRAS.

It's the most frequently mutated cancer-causing gene we know of, and it's often implicated in lung, colon, and pancreatic cancers. KRAS makes a protein also called KRAS, which relays signals from outside of the cell into the nucleus. Those signals tell the cell when it's time to grow and divide.

KRAS basically acts as a molecular switch: when it's on, it relays signals to the nucleus; when it's off, it doesn't. It does that by binding to two different forms of a particular molecule. GTP is the “on” form that lets those signals flow, while GDP turns it off and halts the signals.

So normally, the KRAS protein will bind to GTP and send growth signals for some amount of time, then it'll convert that GTP into GDP, and growth will stop. But when there's a mutation in the KRAS gene, things don't go according to plan. One particular mutation sometimes seen in cancer, known as KRAS G12C, prevents the protein from converting GTP into GDP.

In other words, it keeps those growth signals from turning off. If you could create a drug that could lock the KRAS gene in its “off” state, you could potentially slow or stop the growth of tumors caused by that mutation. That's precisely what the drug AMG 510 does.

It binds to the KRAS protein and makes it behave just as it would if it were bound to the “off” molecule GDP. Last year, AMG 510 began clinical trials, making it the first treatment of its kind to reach clinical testing in humans. Before you get too excited, I should mention that this is a phase 1 trial.

That means that the trial is only looking at safety, side effects, and the best dose and timing for the treatment. Testing for effectiveness comes later. Even so, this week we got some results from those trials, and things are looking pretty good.

Two patients with lung cancer saw their tumors shrink by 34% and 67%, respectively, after just six weeks of treatment. And both remained on the treatment for months after that -- and seemed to be tolerating it well when the study was written up. The researchers also found that AMD 510 could be even more effective when combined with immunotherapy, a treatment that trains the body's own immune cells to fight cancer growth.

Overall, AMD 510 is looking like it's safe at the dose being tested, and there's some preliminary evidence that it can fight tumors in lung cancer patients. It'll take more clinical trials to see just how effective it is, but the future is looking bright. Next up, we go from curing cancer… to a bit of not-so-spooky Halloween fun.

We've known for a while that friendship is important. Friendships make people happier and healthier, and even help them live longer. And we humans aren't the only ones who get to experience it.

Many species form close, enduring bonds with each other, and also recognize those bonds in others. But animal friendship is actually tough to study. Like, we can't really ask animals about their pals.

How do you know if two animals are only hanging out because they're in captivity together? Or, if they're in the wild, how do you know they're grooming each other because they're buddies and not because there's some other complex social factors at play? To untangle questions like these, researchers based in Germany performed an experiment with the ultimate Halloween species: vampire bats.

The results were reported yesterday -- yes, on Halloween -- in the journal Current Biology. They found a hollow tree in Panama that was home to around 200 vampire bats and captured 23 females, some related, some not. They kept these bats in captivity for 22 months and watched to see what kinds of social bonds emerged.

You know, who groomed who, who roosted near who, that kind of stuff. Every so often, they'd withhold food from a few individuals to see who would share with them — which vampire bats do by, you know, regurgitating their blood meal directly into the other bat's mouth. That behavior is really costly for the bat, and it mostly just happens between mothers and offspring.

So if unrelated adults do it, you know they're tight. Like #friendshipgoals. Then, the researchers affixed these bats with tiny backpack sensors and released them back into their tree.

That way, they could keep track of what they did once they were out of captivity. After 8 days of observation, the researchers found that most of the bats that had formed bonds in captivity continued those bonds in the wild. The bats who had cooperated the most together in captivity roosted closer together once they were back in the tree, showing that their social relationships had strengthened while they were away.

Even more importantly, it showed that the friendships researchers have seen in vampire bats previously were likely not just a result of being in captivity. The researchers conclude that vampire bats can form social bonds that are similar to the friendships seen in other species. Studying those friendships can not only help us learn more about animal behavior, but it can also help us understand human bonds a little better, too.

Thanks for watching this episode of SciShow News. It's a new month, and you know what that means: its a new spacecraft pin of the month! For the month of November, you can pre-order this awesome Mariner 9 pin!

This little 70s throwback Mars explorer even has the Red Planet in the background. You can order it through the end of November, after which it'll ship in December and we won't make any of them ever again... but we will make a whole other new pin, so stay tuned to see what that one will be! Check it out at or the merch shelf below this video. ♪♪.