According to an international team of scientists from the United States, Europe and Russia, non-coding parts of the human genome known as vlincRNAs triggered by ancient viruses participate in the development of cancer.
This electron micrograph shows particles of the Phoenix provirus resurrected from human DNA in 2006. Scale bar – 200 nm (Marie Dewannieux et al).
They also found that the elimination of these vlincRNAs (very long intergenic, non-coding RNAs) caused the death of cancer cells.
Dr Philipp Kapranov from the St. Laurent Institute, who is a senior author of a paper published in the journal Genome Biology, said: “understanding this previously ignored part of the human genome, its role in human development, and how it may be taken over by disease, opens a new frontier in science with important implications for medical advances.”
“Future research into the role and function of vlincRNAs holds promise for both highly targeted diagnostic tests and more precise cancer treatments.
Up to 98 percent of human genomic matter is known as ‘junk’ non-coding DNA, and had for years attracted little interest among scientists who doubted its role in human health and disease.
Recent research has begun to identify that part of that non-coding DNA is used by the cell to make RNA such as vlincRNA, highly tissue-specific RNA chains of unusually large lengths, many of which are only found in embryonic or cancerous cells.
VlincRNAs found in these two types of cells tend to be expressed based upon genetic signals from ancient viruses that invaded our ancestors’ genome millions of years ago and were gradually ‘domesticated’ over evolutionary time.
The number of vlincRNAs expressed by these domesticated viral sequences correlates with both embryonic development and malignant cancers.
“St. Laurent Institute has adapted true single-molecule sequencing technology to global transcriptome analysis, providing state-of-the-art technology for the measurement of the output of the human genome.”
“Based upon this technology, we now have a greater understanding of transcriptome regulation, with potential to lead to therapeutic targets and better disease diagnostics,” concluded study lead author Dr Georges St. Laurent III.
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Bibliographic information: Georges St Laurent et al. 2013. VlincRNAs controlled by retroviral elements are a hallmark of pluripotency and cancer. Genome Biology, 14: R73; doi: 10.1186/gb-2013-14-7-r73
