Over recent decades we have made huge progress in survival for many types of cancer, including breast, bowel, testicular, and prostate cancer as well as childhood cancers.
But some types of cancer – including pancreatic, lung, and oesophageal cancers, as well as brain tumours – have remained stubbornly resistant to dedicated efforts of scientists and doctors to improve the situation.
We believe the key to beating cancer is through research – to know what causes the disease in the first place, what drives it to grow and spread, and how best to target it with different treatments. And it’s by working harder to understand these cancers with poor survival rates that we can change the outlook for patients.
Now scientists at our Cambridge Research Institute and the Wellcome Trust Sanger Institute have made an important step forward in understanding one of the most challenging forms of pancreatic cancer.
The researchers have hunted down a crucial gene involved in the disease and, publishing their results in the prestigious scientific journal Nature, have also revealed a potential way to target it.
Sleeping Beauty and jumping genes
Over recent years, scientists around the world have made great strides in understanding the faulty genes that lie at the heart of pancreatic cancer – whether these are inherited gene faults running in families or random mistakes that accumulate over an individual’s lifetime. But there are still gaps in this knowledge, and we know there must be more genes out there.
To fill some of these gaps, Professor David Tuveson and his colleagues turned to mice carrying a faulty version of a gene called KRAS, which puts them at high risk of developing pancreatic cancer. Previous research has shown that this accurately reflects what’s going on in humans, providing a good lab model for studying the disease.
To hunt for new genes involved in pancreatic cancer, the researchers used a “jumping gene” (transposon), known as Sleeping Beauty, which can hop around within an organism’s DNA. When Sleeping Beauty lands within a gene or a region controlling a gene’s activity, it stops it from working properly. (If you want to know more about these fascinating jumping genes, read this article on Wisegeek.)
Under normal circumstances, mice with faulty KRAS genes develop pancreatic cancer relatively late in their lives. So the researchers looked for animals that developed the disease very quickly, where Sleeping Beauty must have ‘jumped’ into a gene that normally helps to protect against pancreatic cancer.
As expected, their experiment revealed a number of genes that have already been implicated in pancreatic cancer in humans, proving that their approach was working. But in over a hundred tumours from mice with ‘early’ cancer, they found that Sleeping Beauty had hopped into a gene called Usp9x, which hasn’t previously been pinpointed as playing a role in pancreatic cancer.
Looking closer, the researchers found that switching off Ups9x in mouse pancreatic cells (using a technique called RNAi) made them grow out of control and stopped them from dying when they should – key characteristics of cancer cells. These experiments strongly suggested that the gene is involved in pancreatic cancer, so why hadn’t previous studies uncovered it?
A faulty switch, not a faulty gene
The answer came when the researchers turned to samples of pancreatic tumours taken from patients. They found very low levels of Usp9x activity in samples from patients whose cancers had spread aggressively, but – surprisingly – didn’t find faults in the actual gene This initially seems a bit strange, but there are additional mechanisms other than being faulty that can switch a gene on or off.
The researchers had an inkling of what might be going on, and so turned next to pancreatic cancer cells growing in the lab. These also had low levels of Usp9x activity. But the scientists treated them with two particular drugs – azacytidine and trichostatin A. These drugs are special because they affect the molecular ‘switches’ (known as epigenetic marks) on DNA that tell a cell whether a gene is active or not. As they suspected, they found that the drugs slowed the growth of the cancer cells.
This confirmed that, in the case of Usp9x, the gene is active in healthy pancreas cells, helping to protect them against becoming cancerous. But if the ‘switches’ are flipped, then Usp9x is inactivated and the cells start growing out of control to form a tumour.
This helps to explain why Usp9x hadn’t turned up before, as most genetic screen are designed to look for faults in the genes themselves rather than these epigenetic ‘switches’
Where next?
Professor Tuveson thinks that Usp9x may be involved in around 15 per cent of pancreatic cancers. It’s also the first common tumour suppressor gene (a gene that protects against cancer) to be found in the disease. This is a significant step forward in our understanding of the molecular faults that drive pancreatic cancer.
Furthermore, the discovery suggests that drugs that alter the epigenetic ‘switches’ on genes may be useful for treating patients. A number of these are currently in clinical trials, and azacytidine is already used to treat some types of cancer. So there are good grounds for future trials investigating the effects of such ‘epigenetic modulator’ drugs in pancreatic cancer patients.
The bigger picture
After years of little progress, we’re now seeing some real movement in the field of pancreatic cancer research, and Professor Tuveson’s lab has been at the heart of much of this work. For example, last February, they published two papers looking at new drug combinations that might prove useful in treating the disease. And just a few weeks ago, they discovered that an enzyme-based drug might be able to break through pancreatic tumours’ tough outer coating, which could ultimately lead to a revolution in how we treat the disease.
Although all this research is still at a relatively early stage, this finding offers hope for future progress in beating pancreatic cancer – a disease that claims far too many lives, far too fast.
Kat
Reference:
Pérez-Mancera, P. et al. (2012). The deubiquitinase USP9X suppresses pancreatic ductal adenocarcinoma Nature DOI: 10.1038/nature11114
Comments
Catherine Boyle June 19, 2012
I lost my mum 10 wks ago and my gran 22years ago to this dreadful disease, both in their early sixties. I was offered gene counselling by one of the consultants but declined. Reading about the progress being made into understanding this disease and possible treatments has given me hope that in the future more people will survive this particular cancer. Thank you x
Kat Arney June 19, 2012
Hi Catherine and Melanie,
We’re so sorry to hear that your families have been touched by cancer, and glad that you have enjoyed reading our blog post about the latest progress in pancreatic cancer.
You may be interested in finding out more about our pancreatic cancer research on our website: http://info.cancerresearchuk.org/cancerandresearch/ourcurrentresearch/researchbycancertype/Pancreaticcancerresearch/
, and you can directly support one of our clinical trials for pancreatic cancer through our MyProjects site: http://myprojects.cancerresearchuk.org/projects/p/category/Pancreatic%20cancer
Best wishes,
Kat
Science Information Manager
Melanie Prince June 16, 2012
Cancer Research please keep up the fight to do more research into how we can combat this terrible cancer. Early testing that GP’s can use and more GP training into the symptoms of this silent killer are desperately needed. My husband lost his mother at the age of 68, only 7 months ago. After countless visits to the GP and going for various tests, throughout last year Jan- Sept, they diagnosed her with diverticultus and sent her home, when in fact she had terminal pancreatic cancer. Bravely end of Sept, she admitted herself to hosptial, only then did she have an emergency scan, the doctors assumed only a blockage in the intestine, maybe a minor operation required, nothing serious. The next day she and we were given the shocking news she had terminal cancer, two days later test results confirmed she had 6months to a year to live. Tragically she passed away only 6 weeks later. We are in our early 30’s and are devastated that this cancer stole the many more years we could have spent together. Cancer Research has done phenomenal research work, raised public awareness for breast cancer, prostate cancer to name but a few. We need more research to increase the survival rate of pancreatic cancer sufferers, thank you
Katie McDonald May 5, 2012
I lost my father to pancreatic cancer in 2000, he was 51. That such advances are being made in the diagnosis and treatment of this dreadful disease, gives me hope for future generations. He never got to see me get married or meet his grandchildren but thanks to the work of you wonderful people, others will get that chance with their own families.
Kat Arney May 8, 2012
Hi Katie,
We’re very sorry to hear about your dad, and share your optimism that research like this will help to keep more families together in the future.
Best wishes,
Kat
Science Information Manager
Sandeep Kumar May 2, 2012
Dear Kat,
Well done and its excellent work.
I am doing research adenocarcinoma pancreatic cancer and working on tumor suppressor gene. We got some promising results on cell line we are using. But we are on quite early stage of research so we cant say any thing yet.
Its quite helpful. Thanks.
Regards,
Sandeep Kumar.
Kat Arney May 2, 2012
Hi Sandeep,
Thanks for your comment, and good luck with your research!
Best wishes,
Kat
Science Information Manager
yuviza April 30, 2012
My husband has adenocarcinoma pancreatic cancer, he is 45 years old. It was discover in july 2010. Since then, he had surgery and several chemotherapy treatments.
He looks very well, but he can´t stop having a treatment because he still has the disease and we know it´s difficult to cure.
We just read about this cancer gens that can help in the treatment for this diagnosis, so it is a hope for us.
We will appreciate to have more information and to know what we have to do to get the opportunity to have this treatment. Maybe you can give us an email to send his medical history if its require.
Thank you.
Kat Arney May 1, 2012
Hi Yuviza,
Thanks for your comment, and we are sorry to hear about your husband. At the moment this research is still in the very earliest stages in the lab, and is not yet developed as a treatment for patients. I’m afraid we can’t offer medical advice through the blog, but you and your husband might find it helpful to talk to his doctor about any clinical trials of new treatments that may be suitable.
Best wishes to you both,
Kat
Science Information Manager
Sandra Whyte April 30, 2012
I lost my husband to this disease in 2006. It was dreadful, he was only 46. Thank you for trying to find a cause and a cure.
Kat Arney April 30, 2012
Hi Sandra,
Thanks for your comment, and we’re sorry to hear about your loss.
Best wishes,
Kat
Science Information Manager
Fahmida April 30, 2012
With runing in families is it beneficial swift migration or more epigenetic study needed.
Lynn Buck April 30, 2012
It is about time. My first husband died of this terrible disease in 2005. He didn’t smoke at all, drink very much or eat in any way excessively and was very keen on keeping fit. It is just frightening the way that any cancer, but particularly this one can just take over someone’s life. He fought it well but finally succumbed after twenty months of struggling. I for one will be very happy when we finally have a cure for all types of this disease.
Kat Arney April 30, 2012
Hi Lynn,
We are very sorry to hear about your husband, and thank you for sharing your story. Our researchers are working hard towards a day when we will beat cancer.
Best wishes,
Kat
Science Information Manager
Dwayne June 28, 2012
Please were can we give a donation to help this research. Thank you