DEC 08, 2016 02:40 PM PST

Cancer is at Least 255-Million-Years-Old, New Study Finds

WRITTEN BY: Xuan Pham
A graduate student interested in how teeth formed in an ancient fossil inadvertently uncovered what researchers are calling the oldest tumor of its kind to date. The discovery suggests cancer is older than even dinosaurs.

Small cluster of circles indicate where the tumor developed | Image: Whitney et al. 2016The fossil is a 255-year-old jaw bone of a gorgonopsian - an extinct animal that lived before mammals. Importantly, gorgonopsians were part of a group known as synapsids, which may be considered our mammal-like reptile ancestors. "Most synapsids are extinct, and we — that is, mammals — are their only living descendants," Whitney said. "To understand when and how our mammalian features evolved, we have to study fossils of synapsids, like the gorgonopsians."

While it was unearthed in 2007, researchers at the University of Washington did not know about the existence of a tumor in their fossil. It wasn’t until Megan Whitney came along and asked the question of how the teeth were nestled in the jaw bones that the team took a closer look at their specimen.

To answer her research questions, Whitney studied slices of the fossilized jaw. Under the microscope, she identified the unmistakable telltale signs of cancer. These were seen as tiny round clusters of miniature ‘toothlets’ at the root of the actual functioning canine tooth. The toothlets seem to have their own layers of dentin and enamel. "this gorgonopsian had what looks like a textbook compound odontoma," Whitney said in a statement.

"We think this is, by far, the oldest known instance of a compound odontoma," said Christian Sidor, the study’s senior author.

In humans an odontoma is a benign tumor linked to teeth development. Formally, odontomas are “miniature teeth that can cause resorption of the functional tooth root.” But while benign, the toothlets that arise can cause swelling and gum pain.

The discovery of the 255-year-old odontoma marks two remarkable milestones. First is that this sample would date cancer to pre-mammalian evolutionary history. In other words, cancer is older than we’ve ever imagined. Second, this type of cancer has not been seen in a non-mammalian animal before. “Odontomas have been reported in a handful of fossil mammals up to a few million years old but were previously unknown in deep pre-mammalian evolutionary history,” the authors wrote. This discovery completely shifts what we know about how cancer has evolved over millions of years in vertebrates.

To learn about the oldest cancer found in a closer relative to humans, check out the video below.
 

Additional sources: Live Science
About the Author
  • I am a human geneticist, passionate about telling stories to make science more engaging and approachable. Find more of my writing at the Hopkins BioMedical Odyssey blog and at TheGeneTwist.com.
You May Also Like
DEC 12, 2019
Cancer
DEC 12, 2019
Early onset colorectal cancer on the rise
New research from the American Cancer Society and recently published in Gut shows that colorectal cancer in young adults is on the rise in high-income coun...
DEC 12, 2019
Cancer
DEC 12, 2019
One third of women don't take advantage of free cancer screenings
Have you ever received a cancer screening? If you haven’t, you’re not alone. New research from King's College London and Queen Mary Univers...
DEC 12, 2019
Drug Discovery & Development
DEC 12, 2019
Evolutionary-Busting Cancer Drug
Researchers at the Institute of Cancer Research in London have discovered that a new type of drug that blocks treatment in cancers. The drug works by inhib...
DEC 12, 2019
Genetics & Genomics
DEC 12, 2019
A Way to Predict Which Microbes Can Cause Cancer
Researchers have created a technique that can identify bacteria and viruses that are linked to cancer....
DEC 12, 2019
Drug Discovery & Development
DEC 12, 2019
The Side-Effects to A Common Blood Cancer Drug
In a study published in Scientific Reports, a popular cancer drug, known as ruxolitnib, was found to cause an increased weight gain as well as an increase ...
DEC 12, 2019
Cancer
DEC 12, 2019
Specific gut bacteria linked to bowel cancer
New research suggests that the presence of a certain kind of gut bacteria can increase the risk of bowel cancer by as much as 15%. The research is importan...
Loading Comments...