Blog Archive

Wednesday, December 16, 2009

The bespoke cancer 'cure': Patients could get specially tailored drugs after British scientists decode damage to DNA

By Fiona Macrae

Researchers at Cambridge University have found the DNA secrets of two forms of cancer, lung and mouth, which could lead to bespoke treatments

Scientists have unlocked the DNA secrets of two of the deadliest forms of cancer.

The breakthrough could lead to 'bespoke' treatments tailored for individual

patients, as well as better detection.

In the landmark study, Cambridge University researchers charted the thousands of pieces of damage to DNA which turn normal cells into lung or skin cancer.

They found more than 23,000 mutations, caused by smoke, in the DNA of a lung cancer cell.

Skin cancer cells were even more damaged, with more than 33,000 mutations, many triggered by sunlight.

It is the first time the entire range of defects that turn a cell cancerous has been laid bare and it has been hailed as a 'transforming moment' in the fight against the disease.

Researchers will now focus on identifying which genetic mutations are the key 'drivers' that fuel the cancer.

This could lead to new drugs and blood tests to pick up the disease in the earliest stages, when it is easiest to treat.

The scientists also hope that studying the genetic damage will enable new and better-targeted treatments.

Every patient could have their own 'mutation chart', mapping the precise flaws behind their illness and indicating the best drugs to treat them.

Professor Mike Stratton was part of the research team who made the discovery

Professor Mike Stratton, of the research team, said: 'We have never seen cancer unveiled in this form before.

'It is like doing an archaeological excavation. We have got traces of all these processes from years before the cancer arose.

'This catalogue of mutations is telling us how the cancer developed and will inform us on prevention.

'If you look back 100 years, that was the moment in which scientists looked down the microscope at cancer cells and saw abnormalities in the nucleus and speculated it was these that were responsible for the generation of cancers.

'Now we are looking at the same nucleus of the cancer cells using a different microscope - DNA sequencing - and we are able to decode almost every single mutation present. This is a really transforming event.'

The research, funded by the Wellcome Trust, was made possible by advances in technology which allow huge strands of genetic material to be analysed quickly and cheaply.

Scientists have now started reading the DNA of other types of cancer, including breast, liver, brain and ovarian.

The journal Nature reported that the vast majority of the lung cancer mutations contained a clear 'signature' of the poisons in cigarette smoke.

The Cambridge team, working with U.S. academics, calculated that if the cancer takes an average of 50 years to develop, every 15 cigarettes bring a smoker one mutation closer to the disease.

The process could happen much more quickly, however, as no one can currently predict when the key 'driver' mutations will occur.

Researcher Dr Peter Campbell said: 'It is a little like playing Russian Roulette.
'With every packet of cigarettes you are forming mutations in your lungs.

'Most of the time, these will land in completely innocent parts and do nothing. But every so often, when you spin the barrel and produce a bullet, it attacks the DNA in the right place.'

Lung cancer is Britain's biggest cancer killer, claiming 34,500 lives a year.

Malignant melanoma, the most deadly form of skin cancer, affects 10,000 and kills more than 2,000 each year.

Despite medical advances, cancer kills more than half of the 290,000 Britons diagnosed with it each year.

Worldwide, the disease is fatal for seven million people annually.

Professor Carlos Caldas, of Cancer Research UK, said: 'What's so new in this study is that the researchers have been able to link mutations to their cause.

'The hope is that we'll eventually have a detailed picture of how different cancers develop, and ultimately how to better treat and prevent them.'

Sir Mark Walport, of the Wellcome Trust, said: 'This is the first glimpse into the future of cancer medicine'.








source: dailymail