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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 theonform 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 itsoffstate, 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 theoffmolecule 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 cancerto 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

  • themwhich 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 DFTBA.com 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 DFTBA.com or the merch shelf below this video.

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癌症新藥結果和吸血鬼蝙蝠的友誼。 (New Cancer Drug Results and Vampire Bat Friendships)

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    林宜悉 發佈於 2021 年 01 月 14 日
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