19 December 2009
The genetics of a type of lung cancer and a type of skin cancer have been mapped by researchers.
|
Dr Annabel Bentley, assistant medical director for Bupa |
Using a new type of genetic technology, scientists have uncovered the changes (mutations) that cause a type of lung cancer called small-cell lung cancer and a common skin cancer, malignant melanoma. This breakthrough could hold the key to possible treatments and ways of preventing these cancers developing.
The findings were published in two new studies in the journal Nature.
In the first study, researchers discovered over 23,000 mutations that cause small-cell lung cancer. All were closely related to cigarette smoking, a known cause of cancer. A number of specific mutations were directly linked to cancer-causing agents found in cigarettes.
The researchers found that a person who develops lung cancer has smoked on average for 50 years and smoked 7,300 cigarettes each year (about a pack a day). The researchers calculated that for every 15 cigarettes smoked a new mutation develops, and that the effects of one cigarette on the lungs could be much higher than expected.
In the second study, over 30,000 mutations for malignant melanoma were found. Malignant melanoma mutations are closely related to too much ultraviolet (UV) light exposure. Some mutations can occur without UV, but the number of mutations almost doubles with exposure to UV light. The researchers found that the DNA tries to repair some of the mutations, but many mutations cannot be repaired once damaged.
Dr Annabel Bentley, assistant medical director for Bupa, said: "We already know that smoking is the biggest cause of preventable death. This research is a small piece of the puzzle in understanding how smoking causes cancer."
| Key facts |
|---|
|
Pleasance E D Stephens P J O'Meara S et al A small-cell lung cancer genome with complex signatures of tobacco exposure. Nature www.nature.com/doifinder/10.1038/nature08629
Pleasance ED Cheetham RK Stephens P J et al A comprehensive catalogue of somatic mutations from a human cancer genome. Nature. www.nature.com/doifinder/10.1038/nature08658
Back to the latest health news