Cancer gene traced back 600 million years
The gene is shared by humans and ancestral metazoans, and it could reveal important clues about what causes cancer.
Mon, Feb 15, 2010 at 05:49 PM
PRIMITIVE CANCER: Stem cells of ancestral metazoans share a key cancer gene with humans. (Photo: University of Innsbruck)
Researchers from the University of Innsbruck in Austria have retraced the function of an important human cancer gene back 600 million years, according to ScienceDaily.com. The discovery could be a breakthrough both in the understanding of the origins of cancer and the functioning of stem cells.
The gene in question is the oncogene myc, a gene that, when mutated or expressed at high levels, helps turn a normal cell into a tumor cell. Despite some of its more dire consequences, the gene actually plays an important role in the growth of organisms by acting as a gene regulator, determining whether certain other genes are activated or deactivated. In humans, it controls the expression of up to 15 percent of all genes, and a deregulated myc gene occurs in about 30 percent of all human cancers.
Members of the research team at the University of Innsbruck were surprised to discover the same myc gene while examining a primitive fresh water polyp, or Hydra. The ancestral organism has a lineage that traces back at least 600 million years and was one of the first animals to develop on Earth. "It is amazing that we have been able to find this oncogene in such a simple organism," Hydra expert Bert Hobmayer from the Institute of Zoology told ScienceDaily.com
"Because the gene has been conserved in evolution all the way from Hydra to humans, we are now able to analyze biological and biochemical functions of the myc gene in detail and draw conclusions for the human organism," added Klaus Bister, one of the researchers who made the discovery.
Even more interesting, the gene was discovered within the stem cell system of the Hydra, which could lead to interesting hints about the functioning of those cells too. For the Hydra, the stem cells play a crucial role in the organism's regenerative ability.
While the gene's function is not as well-known in humans, the discovery should lead to crucial first steps in new cancer research. "To get a better understanding of the deregulation process caused by the oncogene, we would have to know which genes are regulated by myc and which of these are important for cancers," said Bister.
Even though the full consequences of the research have yet to be pondered, it is nonetheless a profound notion to trace the elementary origins of cancer all the way back to the beginning of animal evolution, predating even the bulk of the Cambrian explosion when most known animal phyla first appeared in the fossil record.