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.
Volunteers in Sweden were tricked into thinking their bodies had vanished, and the "superpower" seemed to ease social fears
Scientists have for the first time captured how taste sensations are processed on the tongue
Researchers set hungry mosquitoes loose on identical and fraternal twins. They found that inherited genes do play a role in making you a mosquito magnet.
State education committee passes a bill banning parents exempting kids from vaccination because of "personal beliefs", as lawmakers around the world discuss similar measures
The torturous trial-and-error process of finding the best cancer drug for an individual could be a thing of the past thanks to a couple of clever devices
A flu strain deadly to chickens and turkeys is striking farms in the West and Midwest. This week, it hit an Iowa facility with millions of egg-laying hens. No one knows how it's entering houses.
Doctors, it turns out, often don't follow evidence-based guidelines. One result? Unnecessary tests. Scientists who study this contrariness think they know why.
Analysis of millions of audio files has led one US company to claim that their software can predict how a person’s voice will make a listener feel
Bird flu outbreak now spreading through Midwest poultry could head east with fall migration
A little MRI video seems to settle the decades-old debate about that loud pop of the joints: It's all about bubbles. But imagine an air bag inflating, not the bursting of a balloon.