Photo by: Getty Images

Getty Images

Tumors Can Grow Teeth

By: Mae Rice

Take a look into the creepy world of teratomas.

August 01, 2019

The human body is pretty creepy. Our immune systems can turn against us; our nervous systems look like scared tassels; and the skeletons we use as Halloween decorations are literally inside us all the time. There's something even worse, though: We can grow tumors. Not just regular tumors, but tumors with teeth.

Cancer cell, computer illustration.

758305375

Cancer cell, computer illustration.

Photo by: Getty Images/KATERYNA KON

Getty Images/KATERYNA KON

Meet the Teratoma

These teeth-bearing tumors are called teratomas, which is Greek, roughly, for "monstrous tumors." No kidding. Teratomas haven't just been known to sprout teeth. They've been known to contain all kinds of tissue: bone, muscle, hair, and elements of a nervous system. Teratomas have been discovered with eyes; in one benign teratoma found in a 16-year-old girl, doctors found "well‐differentiated and highly organized cerebellar tissue" in "a skull‐like, bony shell" — in other words, the beginning of a brain and brain stem in a skull.

Her teratoma was unusually developed (just to reiterate: it had a skull!), but in many ways, it was a typical mature teratoma. Mature teratomas can be big, like hers, and painful. They can even be persistent; sometimes they grow back once removed. However, they typically aren't dangerous. It's immature teratomas, whose cells have yet to differentiate into multiple tissue types, that have the most potential to develop into cancer.

The 16-year-old's teratoma was found in her ovary. This is a common teratoma spot for women; in fact, they account for between 10 and 20 percent of ovarian growths. It's no surprise that they cluster around a woman's reproductive system, either. Teratomas are essentially embryonic tissue erupting spontaneously in places that it shouldn't. (That's not to say they only develop in women, though. In men, teratomas most often appear in the testicles, and they've also been found in children, typically on the tailbone.)

But Why So Toothy?

Don't worry. Teratomas can grow teeth, not through dark magic, but through the normal magic of germ cells — the type of stem cell that turns into an egg or sperm cell, which in turn can produce a fetus. Germ cells are "pluripotent," as scientists put it, which means they can produce all different types of tissue.

When germ cells go rogue, though, teratomas arise. Really, all it takes is one germ cell going rogue. In the 1960s, embryologist Barry Pierce discovered that the root of every teratoma is a single germ cell, which produces a constant stream of new and varied cells that accumulate into a tumescent mass. Meanwhile, all the other cells in the tumor lead normal cellular lives and ultimately die off. In other words, teratomas are a case of a bad apple ruining the bunch.

Research on teratomas like Pierce's had implications that extended beyond the toothy tumors, too. The discovery that one cell could create many types of cells — so, the discovery of pluripotency — ultimately led to the discovery of stem cells in the 1980s, a breakthrough with massive mainstream implications. Stem cells are the key to cloning mammals and (less controversially) to growing isolated human organs, like hearts, for people who need transplants.

So in the end, teratomas really aren't as horrifying as they sound. They're mostly benign, and they led science to a groundbreaking and potentially life-saving discovery. Just as you shouldn't judge a book by its cover, perhaps you shouldn't judge a tumor by its teeth, hair, and fully developed eyeball.

This article first appeared on Curiosity.com.

Next Up

Gallium Is A Metal That Melts In Your Hands

Gallium will change your perception of metal.

Scientists Are Resurrecting the Tasmanian Tiger from Extinction

Colossal Biosciences has announced it has begun work on the de-extinction of the thylacine, an iconic Australian marsupial eradicated by human hunting in 1936. Learn how they plan to do it in an exclusive interview with marsupial evolutionary biologist Andrew Pask Ph.D. and Colossal Co-Founder Ben Lamm.

The AuthaGraph Is The World's Most Accurate Map

View the world in correct proportions with this map.

What If Dark Matter Doesn't Exist and the Law of Gravity Is Wrong?

Dark matter and gravity have scientists at odds.

Here's Why Sound Carries Farther on Cold Days

It's not in your head—you hear better on cold days.

Why You Can’t Escape a Mosquito

Hiding the scent of human blood from mosquitoes is harder than scientists originally thought.

Extreme Weather Tests the Durability of Solar and Wind Power

As category four Hurricane Ian swept across the Caribbean into south west Florida on 28 September 2022, knocking out Cuba’s electricity grid along the way, hundreds of thousands of homes were hit by flooding and power loss. In contrast, the solar-powered community of Babcock Ranch 24 miles to the north of coastal town Fort Myers survived intact.

How 3D Print Building is Changing the Future

Building with 3D printing technology is sparking widespread interest in the construction industry. Besides reducing waste and our impact on the environment, it can speed up construction from weeks, or months, to days. Projects that use simple raw materials like soil, straw, and even salt, can be built in a fraction of the time and cost of traditional construction.

Microplastics in Blood Spotlight Health Emergency from Plastic Pollution

Plastic pollution is growing rapidly across Earth’s ecosystems and its threat to humanity and wildlife is too. Outcomes for health and the environment will be dire unless we tackle it, says a United Nations (UN) report. But the discovery of microplastics in human blood means urgent action is needed.