'Junk DNA' drives cancer growth

May 02, 2010

Researchers from the University of Leeds, UK, the Charite University Medical School and the Max Delbruck Centre for Molecular Medicine (MDC) in Berlin, Germany, have discovered a new driving force behind cancer growth.

Their studies have identified how 'junk' DNA promotes the growth of in patients with Hodgkin's lymphoma. Professor Constanze Bonifer (University of Leeds) and Dr Stephan Mathas (Charité, MDC) who co-led the study suspect that these pieces of 'junk' DNA, called 'long terminal repeats', can play a role in other forms of as well. The work is published in Nature Medicine.

The researchers uncovered the process by which this 'junk DNA' is made active, promoting .

"We have shown this is the case in Hodgkin's lymphoma, but the exact same mechanism could be involved in the development of other forms of blood cancer," said Prof. Bonifer. "This would have implications for diagnosis, prognosis, and therapy of these diseases."

'Long terminal repeats' (LTRs) are a form of 'junk DNA' - genetic material that has accumulated in the human genome over millions of years. Although LTRs originate from viruses and are potentially harmful, they are usually made inactive when embryos are developing in the womb.

If this process of inactivation doesn't work, then the LTRs could activate cancer genes, a possibility that was suggested in previous animal studies. This latest research has now demonstrated for the first time that these 'rogue' active LTRs can drive the growth of cancer in humans.

The work focused on cancerous cells of Hodgkin's lymphoma (the Hodgkin-/Reed Sternberg cells) that originate from white blood cells (antibody-producing B cells). Unusually, this type of lymphoma cell does not contain a so-called 'growth factor receptor' that normally controls the growth of other B-cells.

They found that the lymphoma cells' growth was dependent on a receptor that normally regulates the growth of other immune cells, but it is not usually found in B-cells. However in this case, the Hodgkin-/Reed Sternberg cells 'hijacked' this receptor for their own purposes by activating some of the 'junk DNA'. In fact the activated hundreds, if not thousands, of LTRs all over the genome, not just one.

Hodgkin-/Reed Sternberg cells may not be the only cells that use this method to subvert normal controls of cell growth. The researchers found evidence of the same LTRs activating the same growth receptor in anaplastic large cell lymphoma, another blood cancer.

The consequences of such widespread LTR activation are currently still unclear, according to the study's authors. Such processes could potentially activate other genes involved in tumour development. It could also affect the stability of chromosomes of cells, a factor that may explain why Hodgkin-/Reed Sternberg cells gain many chromosomal abnormalities over time and become more and more malignant.

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ddoingit1
May 02, 2010
This comment has been removed by a moderator.
Bob_Kob
5 / 5 (2) May 03, 2010
You have got to be the dumbest person ive ever heard posting on ANY forum. Did you even read what you said?
Dunbar
May 03, 2010
This comment has been removed by a moderator.
Julian_Noble
5 / 5 (1) May 03, 2010
You have got to be the dumbest person ive ever heard posting on ANY forum. Did you even read what you said?


I suspect that posting was by a troll-bot. I wish I could say with a straight face that 'only software could be that stupid', but I have to admit it could be a human and it's possible somebody actually 'thought' they were thinking when they wrote that.
KBK
4 / 5 (1) May 03, 2010
I don't think that English is their mother tongue. Not so bad if you put in the effort. Everyone has an opinion and a viewpoint. To angrily deride and demand homogenization of and for them --is to kill us all. Individualism is the key component of humankind. Release yourself from the body's given deamon, the ego, do everyone around you -and yourself- such a favor. Do this enough to consider the efficacy of self-reflection in the realm of human growth.
Bob_Kob
not rated yet May 07, 2010
Individualism is the key component of humankind.


If by individual you mean complete nutjob then be my guest.

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