New Cancer Treatment “Remembers” Tumors and Won’t Let Them Regrow

iStock
iStock

Researchers have found a way to train the immune system to eradicate cancer cells and “remember” them in case they try to return. A report of the technique was published today in the journal Science Immunology.

Cancer is a stealthy invader. Rather than facing the body’s defenses head-on, it manipulates the sentries of our immune system, shutting them down or even turning them against us.

One commonly hijacked sentry is called the CD4+ T regulatory (Treg) cell. When they’ve been bamboozled by cancer, Treg cells tell our defenses to leave tumors alone. So if we could find a way to shut those Treg cells up, our immune systems would, theoretically, treat cancer like the intruder it is. The problem is that Treg cells are themselves kind of slippery and hard to target with drugs.

One possible way in is a molecule called LAP, which has previously been linked to worse outcomes for people with cancer.

To learn more, researchers examined interactions between Treg cells and LAP in mice with melanoma, colon cancer, and brain cancer. They found that zapping the molecule with special anti-LAP antibodies did the trick, effectively shutting the hijacked cells down so the immune system could do its work. Mice treated with these antibodies had lower levels of Treg cells and cancer cells.

Better yet, when the researchers mixed the anti-LAP antibodies with tumor vaccines, they discovered that tumors wouldn’t grow, even in mice exposed to cancer-causing proteins. The effects of this cocktail lasted for months.

Best of all, the treatment seemed to create “memories” of the tumors in the rodents’ immune systems, enabling them to recognize cancer cells more quickly and prevent relapse.

Before you get too excited, we should mention a few things about these experiments. First, as we’ve said before and will say again, mice are not people. Second, the treatments were tested under the mice’s skin, not in the places where these tumors would naturally grow.

Still, the researchers say, the anti-LAP molecules are a good step, and they are eager to explore them further.

Lítla Dímun: The Smallest of the Faroe Islands Has Its Very Own Cloud

While some islands are known for their unusual geography or unique history, Lítla Dímun is notable for its weather. The island, which is the smallest of Denmark's Faroe Islands chain, is often capped by a lens-shaped cloud, making it resemble a scene from a fairytale.

According to Mental Floss's own Kerry Wolfe writing for Atlas Obscura, the cloud floating above Lítla Dímun is a lenticular cloud. This type of cloud forms when moist air flows over a protruding geological feature, like a mountain top. When the wind moving up the landmass hits the air current directly above it, a sort of wave is created on the downwind side of the mountain. The moist air falling down this wave evaporates and then condenses into a large, flying-saucer-shaped cloud atop the mountain peak as a result.

Another factor that makes Lítla Dímun distinct is that it's the only one of the 18 main Faroe Islands without human inhabitants. Visitors to the mystical location will instead find a thriving population of sheep. Originally, Lítla Dímun was home to a group of feral sheep likely dating back to the Neolithic era. But they were hunted to extinction in the 19th century. Domesticated sheep were introduced there around the same time, and today, farmers visit the island once a year to round up their flocks.

One of the few signs of human life are the ropes farmers use to scale the cliff faces bordering the island. Even if you have rock-climbing skills, Lítla Dímun may be dangerous to visit. A boat ride to the rocky shore is only possible when the surrounding sea is calm.

[h/t Atlas Obscura]

Why Are Sloths So Slow?

Sloths have little problem holding still for nature photographers.
Sloths have little problem holding still for nature photographers.
Geoview/iStock via Getty Images

When it comes to physical activity, few animals have as maligned a reputation as the sloth. The six sloth species, which call Brazil and Panama home, move with no urgency, having seemingly adapted to an existence that allows for a life lived in slow motion. But what makes sloths so sedate? And what horrible, poop-related price must they pay in order to maintain life in the slow lane?

According to HowStuffWorks, the sloth’s limited movements are primarily the result of their diet. Residing mainly in the canopy vines of Central and South American forests, sloths dine out on leaves, fruits, and buds. With virtually no fat or protein, sloths conserve energy by taking a leisurely approach to life. On average, a sloth will climb or travel roughly 125 feet per day. On land, it takes them roughly one minute to move just one foot.

A sloth’s digestive system matches their locomotion. After munching leaves using their lips—they have no incisors—it can take up to a month for their meals to be fully digested. And a sloth's metabolic rate is 40 to 45 percent slower than most mammals' to help compensate for their low caloric intake. With so little fuel to burn, a sloth makes the most of it.

Deliberate movement shouldn’t be confused for weakness, however. Sloths can hang from branches for hours, showing off some impressive stamina. And because they spend most of their time high up in trees, they have no need for rapid movement to evade predators.

There is, however, one major downside to the sloth's leisurely lifestyle. Owing to their meager diet, they typically only have to poop once per week. Like going in a public bathroom, this can be a stressful event, as it means going to the ground and risking detection by predators—which puts their lives on the line. Worse, that slow bowel motility means they’re trying to push out nearly one-third of their body weight in feces at a time. It's something to consider the next time you feel envious of their chill lifestyle.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

SECTIONS

arrow
LIVE SMARTER