June 7, 2013
Researchers Find Evidence Of World’s Oldest Cancer In Neandertal
Lawrence LeBlond for redOrbit.com - Your Universe Online
Modern day exposure to pollution, toxins, radiation, and even unhealthy foods are considerable factors in the risk of future cancer. And because these factors are associated with modern society, it is especially rare to find cancers in earlier civilizations.
Still, cancers have been found previously in ancient cultures; the oldest was in an Egyptian mummy from about 2,200 years ago. While that was a remarkable find for researchers, since tumors in fleshy tissue usually decay and typically do not fossilize, another discovery blows the doors off that tumorous treasure.
An international team of researchers from University of Kansas (KU), University of Pennsylvania (UPenn), Princeton and the Croatian Natural History Museum have recently discovered evidence of fibrous dysplasia (bone cancer) in the rib of a 120,000-year-old Neandertal from Krapina, Croatia. The findings are to be published in an upcoming edition of PLoS ONE.
“It´s evidence that Neandertals suffered tumors – that they were susceptible to the same kinds of diseases that we see in modern humans,” said David Frayer, professor of anthropology at KU, who co-authored the paper. “Before this, the earliest tumor in bone that we´ve seen goes back to an Egyptian mummy. So this is 100,000 years older than the previous tumor that has been found. There is no evidence of cancer older than this in the human fossil record.”
The researchers are unclear if the remains were that of a female or a male since the skeleton was incomplete. They also can´t tell how old the individual was at time of death, or even the cause of death, noted Frayer.
Frayer said that it is possible that the cancer was spread throughout the individual´s other bones, but no other evidence was found. “At this site, there are more than 900 bones, but very few of them are associated one with the other. And while there are other pathologies, none of the others show evidence of a tumor.”
Most scientists have conjectured for years that Neandertals didn´t share any genealogical lineage with modern humans. However, in recent years, genetic research has been discovered that ties us to the ancient hominids, making them the forefathers of modern humanity.
“We have actual nuclear DNA from a number of different Neandertals – not complete sequences – but segments of nuclear DNA,” said Frayer. “So we know that Neandertals have a set of unique genes that were passed on to modern humans. It´s about 4 percent of our genetic makeup.”
As for the tumorous rib, the team said it was a 1.2-inch-long fragment of the left rib, which shows sign of breakage. The break exposes a chamber that is 0.7 inches in length and 0.3 inches wide. The unusualness of the cavity is that it should be filled with cancellous bone. However, radiography and CT imaging showed signs that it was the site of a benign tumor associated with fibrous dysplasia.
According to the US National Library of Medicine (NLM), fibrous dysplasia is a bone disease that destroys and replaces normal bone with fibrous bone tissue. It is a developmental disorder that typically occurs in childhood, usually between the ages of three and 15. It is not hereditary and the cause is unknown; there is no known cure for the disease.
In the case of the Neandertal, Frayer said it is difficult to ascertain how severely the tumor affected him/her.
“It wasn´t a small tumor,” Frayer said. “It was a fairly large one, probably bulging at the base of the rib. We´re not sure how far along it was, but it was well-expressed in the bone. It was in the upper third of the back, and muscles attach there that are associated with raising the arm.”
The research team included Janet Monge and Morrie Kricum of UPenn, Alan Mann of Princeton, and Jakov Radovcic and Davorka Radovcic of CNHM.
Image Below: Fibrous tumor found in a rib fossil from a 120,000-year-old Neandertal. Credit: University of Kansas