A large-scale American study has pinpointed a number of new regions within the genome associated with the development of lung cancer: the world's biggest cancer killer. Researchers hope their findings will lead to new and improved treatments.
The $1million multi-centre study, published online in Nature, screened the genome looking at SNPs (single nucleotide polymorphisms) - single letter 'variants' -looking for correspondence between more than 500 tumour specimens.
'This view of the lung cancer genome is unprecedented, both in its breadth and depth,' said Matthew Meyerson, of the Broad Institute in Cambridge, Massachusetts, who led the study. 'It lays an essential foundation, and has already pinpointed an important gene that controls the growth of lung cells. This information offers crucial inroads to the biology of lung cancer and will help shape new strategies for cancer diagnosis and therapy.' 50 unique regions were identified, with more than two-thirds in areas not previously implicated in lung cancer. The identification of one gene in particular is causing excitement amongst researchers. The NKX2.1 gene - apparently duplicated many times in lung cancer - operates normally as a 'master regulator' - controlling the activity of other key genes in cells called alveoli- hollow cavities in the lungs that are the primary site of oxygen absorption. Despite only being expressed in the alveoli, NKX2.1 appears to promote cancer growth making it a ripe target for future treatments.
There are around 40,000 cases of lung cancer diagnosed in the UK each year, and around 33,500 deaths, giving it the lowest survival rates of any cancer: only seven per cent of patients are alive after five years. Although 90 percent of lung cancer is induced by genetic damage from smoking, genetic predisposition to the disorder is known to be important in the development of the disease.
The SNP screen is a prequel to a much larger $8million study employing gene sequencing, which has a much higher resolution, to identify more subtle genetic changes in lung cancer. 'You ain't seen nothin' yet,' said Meyerson.