Researchers at Karolinska Institutet in Sweden have identified a new so-called pseudogene that regulates the tumour-suppressing PTEN gene. They hope that this pseudogene will be able to control PTEN to reverse the tumour process, make the cancer tumour more sensitive to chemotherapy and to prevent the development of resistance. The findings, which are published in the scientific journal Nature Structural and Molecular Biology, can be of significance in the future development of cancer drugs.
The development of tumours coincides with the activation of several cancer genes as well as the inactivation of other tumour-suppressing genes owing to damage to the DNA and to the fact that the cancer cells manage to switch off the transcription of tumour-suppressor genes. To identify what might be regulating this silencing, the researchers studied PTEN, one of the most commonly inactivated tumour-suppressor genes. It has long been believed that the switching-off process is irreversible, but the team has now shown that silenced PTEN genes in tumour cells can be 'rescued' and re-activated by a 'pseudogene', a type of gene that, unlike normal genes, does not encode an entire protein.
"We identified a new non-protein encoding pseudogene, which determines whether the expression of PTEN is to be switched on or off," says research team member Per Johnsson, doctoral student at Karolinska Institutet's Department of Oncology-Pathology. "What makes this case spectacular is that the gene only produces RNA, the protein's template. It is this RNA that, through a sequence of mechanisms, regulates PTEN. Pseudogenes have been known about for many years, but it was thought that they were only junk material."
No less than 98 per cent of human DNA consists of non-protein encoding genes (i.e. pseudogenes), and by studying these formerly neglected genes the researchers have begun to understand that they are very important and can have an effect without encoding proteins. Using model systems, the team has shown that the new pseudogene can control the expression of PTEN and make tumours more responsive to conventional chemotherapy.
"This means that we might one day be able to re-programme cancer cells to proliferate less, become more normal, and that resistance to chemotherapy can hopefully be avoided," says Per Johnsson. "We also believe that our findings can be very important for the future development of cancer drugs. What we're seeing here is just the tip of the iceberg. The human genome conceals no less than 15,000 or so pseudogenes, and it's not unreasonable to think that many of them are relevant to diseases such as cancer."
'A pseudogene long noncoding RNA network regulates PTEN transcription and translation in human cells', Per Johnsson, Amanda Ackley, Linda Vidarsdottir, Weng-Onn Lui, Martin Corcoran, Dan Grandér och Kevin V. Morris, Nature Structural and Molecular Biology, AOP 24 February 2013, doi: 10.1038/nsmb.2516.
Karolinska Institutet: http://info.ki.se/ki
This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.
Doctors have used perfect replicas of childrens' hearts to uncover and repair hidden defects
An experiment testing people’s altruism in the face of electric shocks is clear on one thing: we are drawn to these little blasts
Researchers gear up tests in West Africa to see whether blood from Ebola survivors can help people who are sick with the disease. This is part of a broader effort to test therapies in West Africa.
The virus's foray into Europe coincides with peak production of Christmas turkeys, the poultry species most vulnerable to bird flu
A novel kind of nanoparticle could lead to more effective cancer treatments.Patients and doctors often don’t know if surgery to remove cancerous tissue was successful until scans are performed months later. A new kind of nanoparticle could show patients if they’re in the clear much earlier.
One challenge in evaluating the effectiveness of different medical procedures, is that patients behave differently after different procedures. Is this true for patients getting heart surgery?
It is only in the aftermath of treatment that survivors discern that their adrenalin alone wont fuel the rest of their recovery. For many, surviving cancer is followed by even more hardship
Just down the road from Facebook and Google, Dr. Phil Wagner runs a laboratory dedicated to optimizing the performance of some of the world's top athletes. At Sparta Performance Science in Menlo Park, California, Wagner and his team bring the spirit of Silicon Valley to bear on the athletic world, helping athletes find the tiny advantages that add to championships. Join us for a trip inside the lab to see where sports meets science.
Pieter Cohen, an internist in Massachusetts, got interested in dietary supplements several years ago, when some of his …
The risk of overdiagnosis and false positives means the UK may be barking up the wrong tree in trialling a wider target age range for breast screening