Possible location of lung cancer genes
Scientists from Dana-Farber Cancer Institute has located the genes causing lung cancer using a DNA probe, which can probe the smallest segments of the genetic code. The researchers used single nucleotide polymorphism (SNP) array technology, which looks for the building blocks of individual genes, to identify regions of chromosomes where genes were either left out or multiplied over and over, abnormalities that are often associated with cancer. In this effort, SNP arrays have been used to find gene, copy errors in lung cancer cells. Researchers have published these findings in the July1 issue of the journal Cancer Research.
"In a previous study, we showed that SNP arrays offer a unique way of locating copy-number changes in cell chromosomes and of determining when genes on a pair of chromosomes are mismatched," says the study's senior author, Matthew Meyerson, MD, PhD, of Dana-Farber. "The current study demonstrates that high-resolution SNP technology is powerful enough to identify copy-number alterations that previously hadn't been found in lung cancer cells."
Working with 70 specimens of lung cancer tissue and 31 laboratory-grown lines of lung cancer cells, the investigators used high-resolution machinery to scan the cells' chromosomes in 115,000 locations. They found several areas that had already been identified as having copy-number errors, plus five new ones -- two where genes had been deleted, and three where they had been highly over-copied.
The next step will be to identify the specific genes involved in these alterations. That, in turn, could lead to new diagnostic tests and treatments for lung cancer, by far the most common form of cancer in the United States, and one of the most difficult to treat.
There is increasing evidence that therapies aimed at specific gene abnormalities can be effective in treating cancer. Last year, for example, Meyerson and colleagues demonstrated that the drug Iressa shrank tumors in patients with the most common form of lung cancer who carry an abnormality, or mutation, in a single gene.
|
