Gene clue in smokers' lung cancer
Scientists have found a genetic alteration that occurs in a common
type of lung cancer in smokers, which they say provides a target for
developing much-needed new drugs against the often deadly tumours.
In a study published in the journal Science Translational Medicine, a
German-led team of researchers said a gene known as FGFR1 was 'a new
suspect' in squamous cell lung cancer and their findings may lead to
targeted drugs for patients whose current treatment options are limited.
Scientists said the findings suggest that drugs known as FGFR
inhibitors, designed to block the function of this gene, could
prove useful against this type of squamous cell lung cancer.
Reuters |
"Until now, the news for patients with such cancers has not been
good," Institute of Cancer Research in London representative Nicholas
Turner, who wrote a commentary in the same journal said. He said,
however, that this study provided "the first glimmer of hope".
Lung cancer is the leading cause of cancer death worldwide, killing
up to 1.3 million people a year, according to the World Health
Organization. The vast majority of cases are caused by smoking.
Non-small cell lung cancer accounts for around 80 percent of cases
and is divided roughly equally into two main groups - adenocarcinomas
and squamous carcinomas. Squamous cell lung cancer tends to respond
poorly to both chemotherapy and radiotherapy, and there are as yet no
targeted drugs for it.
The researchers, led by Roman Thomas at the Max Planck Institute for
Neurological Research in Germany, created gene profiles of a large set
of lung cancer cells and found that squamous cell lung cancer samples
contained more copies of the FGFR1 gene than other cancer types.
"We tested a huge cohort of lung cancer patients of all kinds, and we
specifically saw this sub-type only in this particular group of squamous
cell lung cancer patients," Thomas said in a telephone interview.
He said that more than 20 percent of squamous cell lung cancer
samples showed multiple copies of the FGFR1 gene.
Thomas said the findings suggest that drugs known as FGFR inhibitors,
designed to block the function of this gene, could prove useful against
this type of squamous cell lung cancer.
Several drug firms, including Novartis and AstraZeneca, are
developing FGFR inhibitors and have experimental medicines in early
stage clinical trials for other types of cancers such as breast cancer
and myeloma.After identifying the gene clue, Thomas' team used
experimental mice to test an FGFR inhibitor drug and found that it
shrank the tumours.
"What was really striking to us was that it was only the tumours with
the (gene) amplification that showed this extreme sensitivity to the
FGRF inhibitor," Thomas said.
The researchers said that if further clinical trials of these types
of drugs in human patients go well, they could be available for use
within five years.
Dawn |