SUNDAY, April 8, 2012 (HealthDay News) -- An international team of researchers has identified hundreds of new genes that are mutated in stomach cancer, in a finding they say could lead to treatments tailored to the genetic make-up of individual stomach tumors.
Stomach cancer is the second leading cause of cancer death worldwide and kills more than 700,000 people a year, according to the World Health Organization. Treatment is often difficult and unsuccessful. In the United States, less than one-quarter of stomach cancer patients survive more than five years after diagnosis.
"Until now, the genetic abnormalities that cause stomach cancers are still largely unknown, which partially explain the overall poor treatment outcome," said the study's senior author, Dr. Patrick Tan, an associate professor in the Cancer and Stem Cell Biology Program at Duke-NUS Graduate Medical School, in a Duke University Medical Center news release.
Tan, who leads the Genomic Oncology Program at the Cancer Sciences Institute of Singapore, and colleagues from the National Cancer Center of Singapore used DNA sequencing technology to analyze tumor and normal tissue from stomach cancer patients. They identified more than 600 genes that were previously unknown to be mutated in stomach cancer.
Further analysis revealed that two genes -- FAT4 and ARID1A -- were mutated in 5 percent and 8 percent, respectively, of stomach cancers. In some patients, portions of the chromosome containing the two genes were missing. This provides further evidence that genetic defects affecting the two genes occur frequently in stomach cancer.
In lab experiments, the researchers found that changing the functioning of the two genes altered the growth of stomach cancer cells.
"More research is required to realize the clinical implications of these findings. ARID1A and FAT4 are likely also involved in many other cancer types, not just stomach cancer," Tan said.
The study appears online April 8 in Nature Genetics.
The American Academy of Family Physicians has more about stomach cancer.